Insects of Southern Australian Broadacre Farming Systems - Grains ...

© Department 2012 Department of Primary of Primary Industries Industries and Resources and Resources South 

South Australia Australia (PIRSA)(PIRSA), and the the Department of Agriculture of Agriculture and 

and Food Food (DAFWA) Western Western Australia Australia. (DAFWA), and cesar Pty Ltd. 

Copyright protects this publication. Except for purposes 

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of Agriculture Agriculture and and Food Food Western Western Australia Australia (DAFWA). (DAFWA), and 

cesar Pty Ltd. 

ISBN: 978-0-646-53795-5 

ISBN: 978-0-646-53795-5 

This manual was compiled by: 

Judy Bellati, South Australian Research and 

Development Institute (SARDI); 

Peter Mangano, Department of of Agriculture and and Food Food 

Western Australia (DAFWA); 

Paul Umina, cesar CESAR, Pty The Ltd University and the University of Melbourne; of and 

Melbourne; Ken Henry, and South Australian Research and Development 

Ken Institute Henry, (SARDI). South Australian Research and 

Development Institute (SARDI). 

Editing and graphic design provided by: 

Editing Angela and Lush, graphic lush logic design andprovided by: 

Angela Kaylee Lush, Maitland, lush Lavaworks. 

logic; 

Kaylee Maitland, Lavaworks; and 

Michael Graham, T&M Graphic Communications. 

Insects Insects of of Southern Australian Broadacre Farming Systems Identification Manual and and Education Resource © 2010 2012 

i 

i 

SECTION SECTION 1 INTRODUCTION 

1 The development The development of this of edition this edition of I SPY of I has SPY been has been possible possible due to the financial 

due to the financial support support from: from: 

Department of 

Agriculture and Food 

Notification of any errors or omissions are welcome through ken.henry@sa.gov.au, 

Notification of any errors or omissions are welcome through: judy.bellati@sa.gov.au, pumina@unimelb.edu.au, 

pumina@unimelb.edu.au or pmangano@agric.wa.gov.au 

pmangano@agric.wa.gov.au, or kym.perry@sa.gov.au

I I sspy 

p y 

Insects of Southern Australian Broadacre Farming Systems 

Identification Manual and Education Resource 

About I I SPY 

I I SPY forms part part of the of invertebrate the invertebrate identification identification training 

training package package developed developed for broadacre for broadacre crops in crops the southern in southern and western and western grain belt grain regions belt of regions Australia. of Australia. I SPY has 

I SPY been has developed been developed under under the National the National Invertebrate Pest 

Pest Initiative Initiative (NIPI), (NIPI), a a project funded through the the Grains 

Research and and Development Corporation (GRDC). 

I SPY I SPY highlights the the importance of of insect identification 

and and includes key key characteristics used for for identification 

of of important insect and and other arthropod groups 

(collectively referred to to as as invertebrates). 

The The first first three three sections of of I I SPY SPY provide a a general 

introduction and and cover cover basic basic insect taxonomy, external 

anatomy, key key insect orders and and identification keys. keys. 

Section Section four four provides provides detailed detailed information information of of key key 

invertebrates invertebrates that that are are likely likely to to be be found found in in broadacre broadacre 

crops. crops. Each Each invertebrate invertebrate group group (or (or relevant relevant species) species) 

is is covered, covered, with with a a detailed detailed description description of of their their 

key key characteristics, characteristics, lifecycle, lifecycle, damage damage and and specific specific 

management management options options that that can can be be employed. This This 

section section also also covers covers key key biosecurity biosecurity insect insect threats, threats, with with 

an an emphasis emphasis on on the the diagnostic diagnostic characters characters used used to to 

differentiate differentiate major major biosecurity biosecurity pests pests from from established established or or 

native native pests. pests. 

Integrated 

Integrated 

pest 

pest 

management 

management (IPM) 

(IPM) 

is 

is 

discussed 

discussed 

in 

in 

section 

section 

five. 

five. 

I SPY 

I 

is 

SPY 

not designed 

is not designed 

as an all encompassing 

as an all 

encompassing 

IPM document 

IPM 

but 

document 

rather as a 

but 

base 

rather 

level 

as 

manual 

a base 

that 

level 

introduces 

manual 

the 

that 

main 

introduces 

components, 

the 

techniques 

main components, 

and tools 

techniques 

of an IPM 

and 

program. 

tools of 

It outlines 

an IPM program. 

management 

It outlines 

options 

management 

that can be implemented 

options that 

to 

can 

assist 

be 

you 

implemented 

to reduce your 

to 

assist 

reliance 

you 

on 

to 

broad-spectrum 

reduce your reliance 

chemicals 

on broad-spectrum 

for pest control in 

chemicals 

your cropping 

for pest 

system. 

control 

Insecticide 

in your 

modes 

cropping 

of action 

system. 

and 

Insecticide 

their impacts 

modes 

on 

of 

natural 

action 

enemies 

and their 

are 

impacts 

listed, 

on 

and 

natural 

an IPM 

enemies 

decision-making 

are listed, 

flow 

and 

chart 

an IPM 

is presented. 

decision-making flow 

chart is presented. 

Section six provides information on monitoring, 

sampling techniques and economic thresholds. A crop 

monitoring record sheet is also provided, with checklists 

of insect species by crop type and stage. 

Finally, I SPY concludes with a section from Plant Health 

Australia (PHA) on the significance of biosecurity and 

surveillance, and and our our obligation obligation to safeguard to safeguard our industry our 

for industry market for access. market access. 

Southern and western regions 

Southern Australia includes the southern and western grain 

growing regions. 

SECTION 1 1 INTRODUCTION 

ii ii 

Insects of Southern Australian Broadacre Farming Systems Identification Manual and Education Resource © 2012 

Insects of Southern Australian Broadacre Farming Systems Identification Manual and Education Resource © 2010

Disclaimer 

The information provided in this manual is based on 

the best available knowledge and understanding at the 

time of publishing. No person should act on the basis of 

the contents of this publication without first obtaining 

specific, independent professional advice. Recognising 

that some of the information in this document is provided 

by third parties, the governments of South Australia, 

Western Australia, cesar Pty Ltd, the authors, editors and 

the publisher take no responsibility for the accuracy, 

currency, reliability and correctness of any information 

contained in this document. It is the responsibility of 

users to make their kown decision about the accuracy, 

currency and reliability of this information. 

Permission of the publisher is required for reproduction. 

Acknowledgements 

The authors are grateful for all technical contributions, 

information, advice and revision provided in the 

development of this manual. Thanks to the following 

people: 

Susan Ivory, Richard Glatz, Cate Paull, Gabriella Caon, 

Jenny Davidson and Kym Perry (SARDI); 

Hugh Brier, Melina Miles, Kate Charleston and 

Dave Murray (DEEDI); 

Gary Fitt, Nancy Schellhorn and Sarina MacFadyen 

(CSIRO); 

Stuart McColl and Andrew Weeks (cesar Pty Ltd); 

Phil Michael, Svetlana Micic, Darryl Hardie, Rob Emery, 

Dusty Severtson, John Botta, Lisa Sherriff, Doug Sawkins, 

Francoise Berlandier and Alan Lord (DAFWA); 

Sharyn Taylor, Stephen Dibley and Jo Slattery (PHA); 


iii 

SECTION 1 INTRODUCTION 

Joanne Holloway and Louise Rossiter (NSW DPI); and 

Tracey Farrell (Cotton CRC).

Contents 

Section 1. • Introduction 

Section 2. • Basic Insect Taxonomy, External Anatomy, 

Lifecycles and Development 

Section 3. • Important Insect Groups and Identification Keys 

Section 4. • Common Pest, Beneficial and Exotic Species 

Section 5. • IPM Principles and Case Studies 

Section 6. • Monitoring, Record Keeping, Sampling Techniques 

and Economic Thresholds 

Section 7. • Biosecurity 

Section 8. • Glossary 


iv 



v 

SECTION 1 INTRODUCTION

Introduction 

Introduction 

1

SECTION 1 

Introduction 

Over 95% of all animals on the earth are invertebrates 

of one form or another. Invertebrates (animals without 

backbones) include sponges, corals, sea-stars, insects, 

mites, spiders, snails, crabs and worms — to name a 

few. Invertebrates are found in almost all terrestrial 

and aquatic habitats. Over 80% of all invertebrates are 

grouped into the single phylum Arthropoda, which 

includes insects and their allied forms, such as spiders 

and mites. 

The terms invertebrates, insects and arthropods are 

used interchangeably throughout this manual. 

Why do invertebrates become pests 

Many invertebrates are regarded as pests because 

they can destroy crops and are often costly to control, 

resulting in significant economic damage. 

Invertebrates become pests due to a variety of factors. 

• Accidental introduction, e.g. redlegged earth mites 

from South Africa. 

• Native insects adapting to introduced crop plants, 

e.g. native budworm. 

• Changing farming systems, e.g. the use of minimum 

tillage and increased stubble retention favours the 

survival of some pests such as weevils. 

• Simplified ecosystems/monocultures that favour 

certain pests and lessen the impact of natural 

enemies. 

• Local climate/seasonal variation that can determine 

host plant availability and pest population dynamics. 

• Chemical performance that can result in secondary 

pest flare-ups and impact on insecticide resistance. 

Why do we need to consider more 

sustainable management practices 

The long-term prophylactic and routine use of broadspectrum 

pesticides in field crops and the over-reliance 

on chemicals is not a sustainable practice. 

Chemical resistance to various insecticide families 

has already developed in some key pests such as the 

diamondback moth, corn earworm (cotton bollworm), 

redlegged earth mite, some aphids and several grain 

storage pest insects. 

This has become a real concern for the grains industry 

and has highlighted the need to move towards strategic 

and alternative control options that better target the 

pests of concern. 

Integrating a range of effective and sustainable pest 

management strategies will remove the reliance on any 

single method of control in the future. 

Why is correct identification and 

monitoring critical 

• Incorrect identification can lead to costly mistakes. 

The species you find may be beneficial or of no 

consequence and regarded as non-target. Once 

correctly identified, information on the biology, pest 

status and management can be accurately obtained. 

• Correct identification is important for effective 

control, preventing insecticide misuse and potential 

increases in incidences of resistance. 

• Many pests look similar and can be easily 

misidentified. For example, redlegged earth mites, 

blue oat mites, clover mites and Balaustium mites are 

all similar in appearance and size but they respond 

differently to insecticides and rates. Misidentification 

can lead to inappropriate control measures. 

• Modified insect behaviour or the introduction of new 

pests can be recognised early and general awareness 

and preparedness can be increased. 

• Seasonal alerts for irregular and sporadic pests can 

be given in news outlets such as PestFax/PestFacts. 

• Exotic pests can be detected and identified at an 

early stage. 


1 


Accurate identification, monitoring and recording of 

pest and beneficial invertebrates are perhaps the most 

critical skills required to effectively manage pests in a 

sustainable manner and move towards an integrated 

management approach. This is the starting point for the 

I SPY resource manual. 

A basic knowledge of the key invertebrate groups (and 

how to tell them apart) is invaluable when taking those 

first steps towards correct identification. 


I SPY aims to: 

• increase awareness and knowledge of major 

broadacre pest and beneficial species; 

• increase the ability of users to identify key 

invertebrates to order or family level; 

• increase familiarity with invertebrate lifecycles and 

biology; 

• increase familiarity with sampling and monitoring 

techniques as well as record keeping; 

• improve understanding of pest control principles; 

• increase awareness of the role of biological and 

cultural pest control; 

• increase awareness of biosecurity and surveillance. 

2 

SECTION 1 INTRODUCTION

What have I-spyed 

This flow chart can guide you through insect identification using I SPY - either by using the insect identification and 

plant damage symptom keys or the insect diagnostic features on the species pages. 

Have you found an insect 

Can you tell if it is a larva or an adult 

No insect but you have damage 

symptoms to your crop 

If it is a larva, go to 

Section 3, page 12. 

Here you will find an 

identification key that 

will help you identify 

to order. 

If it is an adult, check 

Table 3.2 

‘Key characters of insects 

of agricultural importance’ 

on pages 7-11. Here you 

will find a guide to adult 

forms of various orders. 

Section 3, pages 16 & 17 

has keys for adult beetles 

and moths. 

Go to ‘Crop Damage Pest 

Identification Key’ in 

Section 3. 

Cereals, page 18 

Canola, page 20 

Pulses, page 23 

Pastures & Lucerne, page 25 

Follow the page numbers to the order 

and common species pages. 

Refer to key characteristics in the blue boxes on each 

species page (Section 4) to identify your insect. 

Found your insect 

Check out the information on 

monitoring and control. 

Go to Section 5 for 

IPM information. 

Go to Section 6 for 

monitoring and economic 

threshold information. 

Look for 

this icon 

Not the right insect 

Check the ‘Confused with/ 

or similar to’ information on 

species pages in Section 4. 

OR 

Can you see damage to 

your crop 

OR 

Track down the right insect 

using the sampling techniques 

in Section 6. 


3 


Basic Insect Taxonomy, 

External Anatomy, 

Lifecycles and Development 

Basic 

Taxonomy 

2

SECTION 2 

Basic Insect Taxonomy, 

External Anatomy, Lifecycles 

and Development 

The key taxonomic features that separate invertebrates 

from other groups of organisms are presented in this 

section. The overall body plan is illustrated, as well as 

the two distinct insect lifecycle types and associated 

morphology. 

Taxonomy – a filing system for all living 

things 

Understanding some basics about taxonomy will help 

you understand the different terms for invertebrate 

groups, what they mean and how to identify them. 

Taxonomy is the branch of science that sorts all 

organisms into groups (or taxa) based on their overall 

similarity and relatedness. 

The hierarchy (Linnaean hierarchy) that all living 

organisms fit into has a minimum of seven levels 

(kingdom, phylum, class, order, family, genus, species), 

although there can be many more levels. 

Table 2.1 (p. 3) lists the main taxonomic levels along with 

the broad classifications (distinguishing features that 

separate groups) for invertebrates. 

The most distantly related organisms will be in different 

kingdoms (e.g. plants and animals) and the most closely 

related organisms are likely to be classified into the same 

genus. No two creatures share the same scientific 

name. The unique formal two-word scientific names we 

see are a creature’s genus and species names. 

The generic (genus) is always given with a capital letter 

and the specific (species) is always lower case. Both are 

written in italics and after the first use in text, the genus 

name is often abbreviated to the first letter of the genus, 

e.g. Myzus persicae to M. persicae. Where the species 

name is not known with certainty, the genus name is 

given followed by ‘sp.’ for one species and ‘spp.’ for more 

than one species. 

SECTION 2 Basic Insect Taxonomy, External Anatomy, Lifecycles and Development 

1 


Insect body structure 

Adult body form 

To identify insects it is important to know their basic 

anatomy. Identification keys and insect classifications 

are often based on the adult form. 

There are three distinct regions that make up the 

overall body plan of an adult insect; the head, thorax 

and abdomen. Some parts may be more distinct than 

others and particular insect orders/families/genera may 

have some structures absent, reduced or greatly modified. 

Forewing 

Hind leg 

Abdomen 

Midleg 

Thorax 

Pronotum 

Eye 

Antennae 

Femur 

Mouthparts Foreleg 

Tarsus 

Source: Modified from CSIRO (1991) 

Head 

Tibia 

Immature body form 

It is often the juvenile stages that are the most damaging. 

Juvenile insects can either look similar but smaller than 

mature adults or they can look completely different to 

the adults they will become. 

While the head, thorax and abdomen are usually distinct 

in juvenile insects (nymphs) that undergo partial change 

(incomplete metamorphosis), they can appear merged 

in juvenile insects (larvae) that undergo a complete 

change (complete metamorphosis) with a pupal stage 

(see Lifecycles and development, p. 5, 6). 

An easy way to locate the separate body regions in larvae 

is to look for the legs. True legs (which also become 

the adult legs) are always attached to the thoracic 

segments. However, not all insect larvae have ‘true’ legs 

(e.g. weevil larvae and fly larvae). Some insect larvae, 

particularly moth caterpillars, have fleshy projections 

on their abdomen that resemble legs. These are called 

abdominal or ventral prolegs and assist in locomotion 

and grasping. There can also be anal prolegs, so-called 

because they appear near the end of the abdomen. The 

number of prolegs can be important in identification. 


The HEAD is designed for both feeding and sensory 

purposes and consists of: 

• one pair of compound eyes and up to three simple 

eyes (ocelli); 

• one pair of antennae; 

• mouthparts. Look for differences between chewing/ 

biting, sucking and piercing mouth types (refer to 

section 3) - these are very important in identification. 

The THORAX (middle division) is designed for 

locomotion and is made up of three segments (not always 

distinct). Each thoracic segment (pro-, meso- and metathorax) 

has a pair of legs (resulting in a total of six legs) 

and in almost all winged insects the last two segments of 

the thorax support a pair of wings. Wings are particularly 

important in identification. Flies only have one pair of 

wings that are carried on the middle thoracic segment. 

Some adults can have wingless forms (e.g. aphids). 

The ABDOMEN (rear section) is the largest and softest of 

the three body parts and is designed to hold most of the 

internal organs vital to insect survival and reproduction. 

It contains: 

• internal organs for respiration (spiracles) and 

digestion (stomach); 

• reproductive structures which can often be used 

in identification (e.g. the presence of specialised 

stingers in wasp species); 

• specialised appendages in some cases (e.g. pincers 

on earwigs). 

2 


These general body structures do not hold true for all 

invertebrates, only insects. Others, such as mites, spiders, 

worms, slugs and snails will have different anatomies and 

life stages. For more information see the relevant species 

pages in section 4. 

Moth larva 

Head 

Beetle larva 

First abdominal segment 

Thorax 

Abdominal prolegs 

True legs 

First abdominal segment 

Thorax 

Head 

True legs 

Abdomen 

Anal prolegs 

Abdomen 

Source: Modified from CSIRO (1991)

Table 2.1 Taxonomic category 

Taxonomic category 

KINGDOM 

There are six kingdoms of living creatures - Fungi, Plants, Animals, Eubacteria, Archaebacteria 

and Protista. The last three kingdoms are comprised of simple, mostly unicellular 

organisms. 

PHYLUM 

Vertebrata and Invertebrata 

Humans along with fish, amphibians, reptiles, birds and other mammals, are classified 

into the sub-phylum Vertebrata (phylum Chordata), meaning they have a backbone. 

These are called vertebrates. 

The Invertebrata includes all animals without backbones such as jellyfish, insects, spiders, 

slugs, snails, millipedes, mites, crabs, worms etc. These are called invertebrates. 

Phylum Arthropoda 

Arthropod means jointed-foot. 

Arthro as in arthritis, a joint disease, and pod, as in podiatrist, a foot doctor. 

Arthopods are a group of invertebrates including insects, springtails, mites, spiders, 

ticks and other creatures that are characterised by the presence of: 

• an exoskeleton (hard outer plate coverings) joined by softer tissue 

(i.e. hard on the outside, soft on the inside); 

• jointed limbs (segmented legs). 

The remaining invertebrates (other Phyla) consist of worms, slugs and snails. Unlike 

arthropods, these animals lack segmented legs and are generally soft-bodied. 

Phylum Mollusca (snails and slugs) 

The Mollusca includes snails, slugs, clams, octopuses, squid, oysters, chitons and other 

creatures that share, or are characterised by, the presence of: 

• a muscular foot; 

• non-segmented mouthparts; 

• a radula (set of hooked teeth); 

• a well-developed head. 


3 


Table 2.1 Taxonomic category continued 

Taxonomic category 

CLASS 

Class Insecta (insects) 

Insecta is the largest class of organisms and accounts for over 75% of all animal species. 

Insecta share or are characterised by: 

• a hard outer skin (exoskeleton); 

• a three segmented body (head, thorax and abdomen); 

• six legs (paired segmented limbs arising from the thorax); 

• bilateral symmetry (each side of the body is a mirror image of the other); 

• adults with antennae and two pairs of wings arising from the thorax (wings maybe 

modified or absent). 

Class Arachnida (mites, ticks, spiders and scorpions) 

Arachnida share or are characterised by: 

• two body divisions (cephalothorax and abdomen); 

• adults with four pairs of legs (immature stages have three pairs); 

• a lack of antennae and wings. 

Arachnida includes the orders Acarina (mites and ticks) and Araneida (spiders). 


ORDER 

FAMILY 

GENUS 

SPECIES 

4 

Some other non-insect arthropod classes 

class Collembola (springtails) 

class Diploda (millipedes) 

class Chilopoda (centipedes) 

class Malacostraca (slaters) 

class Crustacea (crabs, lobsters, shrimps, barnacles) 

class Gastropoda (meaning ‘belly feet’) is the only class of agricultural interest in the phylum 

Mollusca. 

This level of classification is most useful when it comes to separating invertebrates into 

broad groups. 

e.g. Lepidoptera (moths and butterflies) 

Worldwide, there are almost 30 insect orders, and almost all of them are represented in 

Australia. 

Refer to Table 3.2 Key characters of insect orders of agricultural importance, section 3 p. 7. 

Families within certain insect orders can be important in terms of pest management. Within 

the order Lepidoptera, the family Noctuidae contains many moth pests such as native 

budworms, armyworms and cutworms. 

e.g. Noctuidae 

Common suffix for super families: - tera or -oidea 

Common suffix for family: - idae 

Common suffix for sub family: - inae 

Genus name is always italicised and first letter capitalised. 

e.g. Helicoverpa 

Species name is always italicised and all lower case. 

e.g. punctigera 

Different species within the same genus can have significant biological differences. For 

example, two moth pests - native budworm (H. punctigera) and corn earworm (H. armigera)- 

belong to the genus Helicoverpa, but H. armigera shows insecticide resistance and has a 

different plant host range to H. punctigera. 

SECTION 2 Basic Insect Taxonomy, External Anatomy, Lifecycles and Development

Lifecycles and development 

Having a basic understanding of a pest’s lifecycle and 

development is important to effectively manage pests. 

By looking at a pest’s lifecycle you can predict the 

occurrence of the most damaging stage to minimise/ 

avoid crop damage, or alternatively to target control at 

the most vulnerable life stage. 

Most insects have the same basic lifecycle, progressing 

from an egg through several immature stages until 

finally becoming an adult, capable of mating and 

reproduction. In the insect world there are two main 

ways to complete this lifecycle. These are described as 

either incomplete or complete metamorphosis, a Greek 

word meaning change. 

Nymphs or larvae hatch from eggs and their survival 

and development is dependant on environmental 

factors (particularly temperature and humidity) and 

the availability of suitable food. For example, the 

diamondback moth lifecycle in relation to temperature 

is as follows: 

- at 12 O C - lifecycle takes approx. 60 days 




Nymphs and larvae grow through a series of moults 

(immature stages). Entomologists refer to these different 

immature stages as instars, i.e. 1 st instar = just hatched, 

2 nd instar = 2 nd immature growth stage, 3 rd instar = 3 rd 

immature growth stage and so on. The number of 

moults will vary depending on the species, but there 

are typically four to eight moults between hatching and 

becoming either an adult (for the nymph) or pupa (for 

the larva). 

In some species, only one cycle or generation occurs per 

year (e.g. the vegetable weevil) whilst in other species 

one generation can take years to complete (e.g. some 

cockchafer species). Multiple generations can also 

occur in one year depending on seasonal conditions 

(e.g. diamondback moth and aphids). Where several 

generations occur in a year, you can often find multiple 

lifestages of a species in a crop at the same time. 


5 


Lifecycles 

Incomplete metamorphosis 

(Hemimetabolism - gradual or partial change) 

Hemiptera 

Insects develop in three stages within this lifecycle: 

egg -> nymph -> adult 

An immature organism within this lifecycle is referred to 

as a nymph (plural nymphs). 

Incomplete metamorphosis is a development process 

in which the immature insect hatches from an egg (or is 

born live in some insects) and gradually turns into an adult 

through a series of moults. Nymphal stages resemble 

miniature adults but with some lack of development in 

general structure (e.g. wings). Their colour and markings 

can be very different. There are usually six to eight 

nymphal stages (moults) depending on the species and 

each successive nymph stage is slightly more developed 

and bigger in size than the previous stage. Nymphs usually 

have similar habits to adults. 

nymphs 

Insects that develop with incomplete metamorphosis 

include grasshoppers and locusts (Orthoptera), bugs 

(Hemiptera) and cockroaches (Blattodea). 

Lepidoptera 


6 

Complete metamorphosis 

(Holometabolism - complete or abrupt change) 

Insects develop in four stages within this lifecycle: 

egg -> larva -> pupa -> adult 

An immature organism within this lifecycle is referred to 

as a larva (plural larvae). 

Complete metamorphosis is a development process in 

which the immature insect bears no visual resemblance 

to, and acts differently from, the adult form. The larval 

stages (instars) are frequently grub-like in appearance. 

Wing-buds develop internally and cannot be seen in 

older larvae. The pupa (plural pupae) is a transition stage 

(often contained within a cocoon/capsule), where larval 

characters are lost and the adult features develop. 

Insects that develop with complete metamorphosis 

include moths e.g. budworms, armyworms (Lepidoptera), 

flies e.g. hoverflies and onion maggot flies (Diptera), beetles 

e.g. cockchafers and weevils (Coleoptera), and wasps e.g. 

parasitoids of aphids and moths (Hymenoptera). 

Pupae 

Pupae 


Adult 

Coleoptera 

Adult 

Egg 

larva or 

caterpillar 

Egg 

larva or 

caterpillar

Important Insect Groups 

and Identification Keys 

Identification 

Keys 

3

SECTION 3 

Important Insect Groups 

and Identification Keys 

Introduction ..............................................................2 

Identification keys .......................................................12 

Larval forms to main orders/families ...................................12 

Beetle larvae to main families. ..........................................13 

Moth/butterfly larvae to main families/species ..........................14 

Beetles (adults) to main families/species ............................... 16 

Moths (adults) to main families/species .................................17 

Crop damage pest identification keys .................................. 18 

Cereals ............................................................... 18 

Canola. ............................................................... 20 

Pulses ................................................................ 22 

Annual pastures and lucerne .......................................... 24 

Tables 

Table 3.1 Mouthpart types and associated damage symptoms ...........4 

Table 3.2 Key characters of insects of agricultural importance ............7 

SECTION 3 IMPORTANT INSECT GROUPS AND IDENTIFICATION KEYS 

1 


Introduction 


The key features to use when identifying invertebrates 

to order level are presented in this section. The 

simplified classification of the invertebrate groups is 

given to assist in the understanding and identification 

of the major orders and families. This section also covers 

the importance of particular mouthpart types and 

associated damage symptoms. 

Less than 1% of the 86,000+ insect species described 

in Australia (and more yet to be named or discovered), 

are considered economic pests. The taxonomy of 

invertebrates is a specialised job that takes years of 

experience. While we can’t recognise all invertebrates 

seen in a crop, the aim is to recognise the most important 

ones in broadacre systems. 

Table 3.2 (p. 7 in this section) is a quick reference guide 

to the main economically-important insect orders (plus 

a few non-insect arthropods) that are likely to be found 

in broadacre field crops. Insects are very diverse and the 

general information presented in this table may not hold 

true for all members of an order. 

Further identification keys to insect orders, families and 

key species can be found in this section. Additional keys 

are widely available via an internet search. 

Useful characters 

General body shape and appearance can be useful in 

distinguishing invertebrate species, e.g. flattened or 

elongated body. Colour and size are useful for some 

adult insects e.g. beetles, but immature stages will vary 

in size and colour. 

The characteristics described below mainly relate to the 

adult form and not the immature or larval stages. 

2 


Head 

• Mouthparts – the type of mouthpart can be 

important (e.g. chewing or piercing/sucking). 

• Antennae – size (relative to the body) and shape can 

be useful. 

• Alignment – whether the front of the head is angled 

down (vertical), slanted forward, exposed or hidden 

can also be important. 

Thorax 

• Number and appearance of wings - absence of wings 

may indicate an immature insect stage or a wingless 

species. Wings have a distinctive appearance, 

particularly at the order level. For example, beetle 

forewings are hardened and called elytra while 

fly hindwings are absent and modified into small 

balance structures called halteres. 

• Legs – some insects may be quite mobile with 

strongly developed legs for running and grasping 

(e.g. predatory beetles and praying mantids), while 

others will have shorter functional legs indicating 

slower movement (e.g. cockchafers). In some 

cases, insects may have greatly reduced or no legs, 

indicating sedentary behaviour (e.g. mealybugs and 

most scale insects). 

Abdomen 

• Special appendages – such as the pincers on the end 

of an earwig’s abdomen. 

• Additional legs (prolegs) on larvae – the number 

of abdominal prolegs can be used to differentiate 

between some pest moth larvae. 

• Join between abdomen and thorax – a key 

characteristic of most ants, wasps and bees 

(Hymenoptera) is that the thorax and abdomen are 

joined either by a broad or narrow waist (constriction).

Other clues 

Frass (faeces) can indicate the kind of insect that may 

be associated with damage (e.g. square, mini haybale 

deposits at the plant base are a tell-tale sign of 

armyworm caterpillars). 

Characteristic soil burrows can also provide some 

indication (e.g. grass or cereal leaves protruding from 

small holes next to damaged plants are characteristic of 

pasture webworm). 

Plant damage can be the first indication of a problem 

and symptoms can be key indicators for the presence 

of certain pest species. Various damage symptoms 

are created by insects and the appearance of these 

is mainly determined by the insect’s mouthpart type 

(e.g. chewing, piercing/sucking). This helps to identify 

the potential culprit causing damage. Further clues can 

be provided by knowing which plants and plant parts 

different pests prefer to feed on. 

Mouth parts are not always easily seen and the type of 

mouth parts can also vary between different insect orders, 

as well as lifecycle stages (i.e. between larvae and adult). 

The main mouthpart types are shown in Table 3.1 (p. 4), 

as well as associated damage symptoms and possible 

pest species. 

This section contains crop damage pest identification 

keys (pp. 18-27) based on plant damage for various crop 

types. When using plant damage as an identification aid it 

is also valuable to note the plant growth stage and the 

parts of the plant that are damaged (e.g. leaves, flowers 

or terminal growing points). 

Caution is needed when using plant damage symptoms 

to help identify pests, as other factors (e.g. disease, 

physiological and nutritional disorders) can often be 

mistaken as insect damage. 

Plant damage symptoms should be used as an aid in 

pest identification but the actual invertebrate should 

be observed before making control decisions. Several 

types of plant damage may be seen which indicates that 

more than one pest could be involved. 


3 


Table 3.1 Mouthpart types and associated damage symptoms 

CHEWING mouthparts 

Pest species generally have mouthparts directed downward, while predatory species generally have enlarged 

mouthparts that are directed forward so that they can catch prey. 

Main mouthpart components 

Hardened jaw structures (mandibles and maxilla), upper lip (labrum), lower lip (labium) and segmented sensory 

extensions (maxillary and labial palps). 

Insects with chewing mouthparts 

Moths and butterflies (Lepidoptera) - the larval stages. 

Beetles (Coleoptera) - both adults and larvae. 

Locusts (Orthoptera) - both adults and nymphs. 

General damage symptoms include chew marks, portions of leaves missing, scalloped leaf edges and 

upper leaf surfaces removed, lopped stems. 

Eye 

Labium 

Frons 

Clypeus 

Labrum 

Mandible 

Ocellus 

Antennae 


Specific chewing damage symptoms 

Above ground 

Green tissue removed from leaves giving an irregular window 

appearance to remaining leaf surface. 

Chew marks – scalloped edges, plant tissue removed. 

Seedlings chewed off at ground level leaving stumps. 

Portions of grass and cereal leaves protruding from holes in the 

ground. 

Chewed portions of heads, pods or maturing seeds lopped off. 

Under ground 

Chewing of roots - above ground leaves stunted, pale or dying. 

Internal chewing of roots in legumes - above ground leaves stunted, 

pale or dying. 

4 

Palps 

Maxilla 



Likely pest(s) 

Lucerne flea or very small moth larvae 

Weevils (adults and larvae) or moth larvae 

Cutworms, weevils 

Webworms 

Budworms or armyworms 

Weevils (larvae) 

Cockchafers 

False/true wireworms 

Sandgropers (WA only) 

Onion maggot fly larvae

Table 3.1 Mouthpart types and associated damage symptoms continued 

PIERCING and SUCKING mouthparts 

Muscles 

Main mouthpart components 

Tough, long, needle-like tube (stylet). 

Pharynx 

Insects with piercing and sucking mouthparts 

True bugs (Hemiptera) e.g. shield bugs, predatory bugs and leafhoppers. 

Mites (Acarina) have scissor-like stylets. 

Salivary duct 

Labrum 

General damage symptoms include bleaching and chlorotic marking, 

distortion, wilting and stunted growth. 

Stylets 


Specific piercing and sucking damage symptoms 

Silvering and distorted leaves. 

Distortion and wilting of growing points, sticky exudates and stunted 

growth. 

Bleaching and chlorotic marks or dotting of leaves in lined patterns 

(distinct trails). 

Likely pest(s) 

Mites 

Aphids 

Leaf hoppers or Bryobia (clover) mites 

LIQUID feeders (modified sucking mouthparts) 

Coiled proboscis: 

Adult moths and butterflies (Lepidoptera) uncoil their proboscis (mouthpart) to feed in flowers and suck liquid 

foods. Most lepidopteran adults are liquid feeders and don’t cause plant damage. 

Blunt trunk-like proboscis: 

Adult flies (Diptera) have this mouthpart structure to suck liquid or soft foods. The mouthparts of biting flies 

(e.g. stable flies, Stomoxys calcitrans) and mosquitoes are modified for piercing and sucking. 

Coiled proboscis 

Butterfly/moth 


Anntenna 

Eye 

Labial palp 

Fly 

Eye 

Antennal 

segments 


Arista 

Blunt 

trunk-like 

proboscis 

5 


Table 3.1 Mouthpart types and associated damage symptoms continued 

MOUTH HOOKS 

Many juvenile flies (Diptera) or maggots have modified mouthparts called mouth hooks. 

Predatory species use this specialised mouthpart to capture (hook) their prey e.g. the larval stage of the hoverfly. 

Mouth hook 

Breathing hole 

(prothoracic spiracle) 

Source: Modified from Peterson (1960) 


RADULA (rasping mouthparts) 

Confined to molluscs (snails and slugs). 

General damage symptoms include shredded edges or strips removed (cereals) and chewing (pulses). 

Seedlings can often be eaten to ground level. 

6 

Radula 

Jaw 

Mouth 

opening 

Source: Modified from Smith & Kershaw (1979) 


Oesophagus 

Radula gland 

Cartilage

Insect type 

Page number 

Lifecycle 

General shape &/or other useful features 

Body region features 

Order (O) 

I SPY 

Section 

4 

Head Thorax 

No. of 

wing 

pairs 


legs 

Mouthparts Antennae 

Ute Guide * 

Wing appearance SA WA 

Transparent 

hindwings concealed 

underneath hardened 

forewings (elytra). 

Lifecycle: complete metamorphosis. 

Usually hard, rounded body shape. 

17 

Adult Forms 

Beetles 

O: Coleoptera 

2 

(usually) 

Chewing Variable 6 

47 

- 64 

37 

- 48 


Wings covered with 

scales in regular 

overlapping rows. 

Butterflies have clubbed antennae and are 

mostly active during daylight. 

Moths are usually active at night. 

2 

18 

- 46 

Moths & butterflies 

O: Lepidoptera 

6 2 

Often 

filamentous, 

multi-segmented 

in females or 

feathery and 

comb-like in 

males. 

Coiled sucking 

tube (proboscis/ 

haustellum) 

Wasps, bees & ants 

O: Hymenoptera 

Prominent, 

17 

- 36 

Ocelli present above each eye. 

Transparent wings. 

Forewings always 

slightly longer than 

hindwings. 

Forewings and 

hindwings are hooked 

together. 


Body usually has a narrow waist 

(constriction) between the first two 

abdominal segments. 

Female has a hardened ovipositor (egg 

laying organ) which can be modified for 

stinging. 

81 

Table 3.2 Key characters of invertebrates of agricultural importance – ADULT FORMS 

119 

- 129 

2 or 

none 

6 

generally with 

nine segments or 

more. 

95 

- 103 

Chewing 


* Crop Insects the Ute Guide, Southern (S.A.) or Western (W.A.) edition 

7 



Table 3.2 Key characters of invertebrates of agricultural importance – ADULT FORMS continued 

8 

Insect type 

Page number 


Order (O) 

Ute Guide * 

Lifecycle 


Head Thorax 


I SPY 

Section 

4 


wing 

pairs 


legs 


81, 

62, 

104, 

116, 

136, 

146 

130, 

140 

169, 

179 


50 

Forewings 

transparent. 

Hindwings replaced 

with knobs (halteres). 

6 1 

One set of wings (key diagnostic feature). 

Typically short 

and simple, frilled 

or brush-like (in 

mosquitoes) 

Flies 

O: Diptera Sponging, 

sucking or 

much reduced 

mouthparts. 

Biting (piercing) 

species have 

mouth hooks. 

Lifecycle: incomplete metamorphosis. 

True bugs 

(e.g. aphids & whiteflies) 

O: Hemiptera 

Sub-O: Sternorrhyncha 


Aphid adults can be winged or wingless. 

Many species have 

wingless adults. 

Piercing & 

sucking 

52 

- 60 

70 

- 79 

33 

Aphids have a pair of cornicles at the base of 

body. 

Usually short. 6 0 - 2 

Sometimes immobile. 

(needle-like 

stylet) 

Scale insects are often sedentary (stuck to 

plant surface). 

Variable. 

Piercing & 

sucking 

65 

- 69, 


Half leathery/half 

membranous 

forewings 

(hemelytra). 

True bugs 

(e.g. mirids, leafhoppers & 

stink bugs) 

O: Hemiptera 

Sub-O: Heteroptera 

49 

- 51, 

61 

80, 

142 

- 144 

33 

6 2 

Wing buds present in late nymphs. 

Transparent and 

veined. 

Clearly 

segmented or 

short and 

bristle-like. 

Waxy in appearance. 

(needle-like 

stylet or 

rostrum 

beak-like). 

Sometimes 

folded under 

the body. 

* Crop Insects the Ute Guide, Southern (S.A.) or Western (W.A.) edition


Insect type 

Page number 


Order (O) 

Ute Guide * 

Lifecycle 


Head Thorax 


I SPY 

Section 

4 


wing 

pairs 


legs 



Earwigs 

O: Dermaptera 

Forceps (caliper-like cerci) at the end of 

abdomen. 

Filamentous, 

59 88 69 

Body often flattened and elongated. 

Large membranous 

wings folded 

underneath shortleathery 

forewings, 

which meet in the 

mid-line and reach 

only a short way 

down the body. 

2 or 

none 

6 

simple and 

slender. 

Chewing 

Many species are wingless as adults. 

Legs are thin and long (adapted for running). 


Lacewings 

O: Neuroptera 

113 - 

114 

137 - 

138 

90 

Slender body. 

Prominent, finelyveined 

wings with 

lots of cross veins. 

6 2 

Filamentous and 

long relative to 

body length. 

Chewing 

(sickle-shaped) 

Wings held roof-like over the body when at 

rest. 

Fore and hindwings 

approx. same size. 


Sturdy body, large head and the pronotum 

(region behind head) is saddle-shaped. 

Grasshoppers, 

crickets & locusts 

O: Orthoptera 

64 - 

68 

83 - 

87 

- 

Hind legs large and adapted for jumping. 

Leathery straight 

forewing, 

transparent fan-like 

hindwing. 

6 2 

Filamentous. 

Long in crickets 

and locusts, but 

short in 

grasshoppers. 

Chewing 

Female with a well developed ovipositor 

(egg-laying organ), usually protruding from 

the tip of the abdomen. 


92 134 108 - 

110 

Two segmented body, cephalothorax 

(fused head & thorax) and abdomen. 

8 none Wingless 

None. 

Use forelegs or 

specialised 

mouthparts 

(palps) in a similar 

way to antennae. 

Spiders 

Class: Arachnida 

O: Araneae Chewing/ 

sucking 

chelicerae 


9 





10 

Insect type 

Page number 


Order (O) 

Ute Guide * 

Lifecycle 


Head Thorax 


I SPY 

Section 

4 


wing 

pairs 


legs 



75 

- 78 

97 

- 

72 

Two segmented body; cephalothorax (fused 

head & thorax) and abdomen. 

none Wingless 

8 (6 in 

nymphs) 

None. Often use 

forelegs as 

sensory tools. 

Mites 

Class: Arachnida 

O: Acarina Chewing/ 

sucking 

chelicerae. 

103 

Spinnerets (web spinning organ) at end of 

abdomen. 

Scissor-like set 

of stylets. 


Springtails 

Class: Collembola 


Two main body forms; cylindrical (elongate) or 

globular (compact). 

Chewing 

63 89 70 

Slightly hairy bodies, abdomen 6 segmented 

with ventral tube. 

6 none Wingless 

Short and 

segmented 

(never more than 

6 segments). 

(hidden by oral 

folds or cheeks). 

Small insects that jump when disturbed using 

a forked tail-like organ (furcula) present 

underneath abdomen. 

Only a few pests (e.g. lucerne flea). 

* Crop Insects the Ute Guide, Southern (S.A.) or Western (W.A.) edition

Lifecycle 

Larval Forms 



Insect type 

Order (O) 

Head Thorax 

Abdominal 

appearance 

Page number 


proleg 

pairs 


legs 

Antennae 

/ Head Capsule 

Mouthparts 

6 

Typically short. 

Beetles 

O: Coleoptera 

Anal proleg rare (e.g. 

Elateridae). 


Typically 4 distinct larval shapes. Some very 

mobile, others less so. 

Can often see the shape of legs and other 

features in pupae. 

I SPY 

Section 

4 

Ute Guide * 

SA WA 

none 

(none in 

weevils) 

Well-defined and 

hardened head 

capsule. 

Chewing 

Short antennae. 

Moths & butterflies 

O: Lepidoptera 

All prolegs with 

crochets (hooks at 

base). 

1 - 4 

pairs. 


Eye spots on side of head. 

‘V’-shaped suture (groove) on front of head. 

17 

47 - 

64 

37 - 

48 

6 

Well-developed 

and hardened 

head capsule, 

usually darker in 

colour. 

Chewing 

Anal 

proleg. 

Flies 

O: Diptera 


Pupae often simple, relatively featureless. 

2 

18 - 

46 

17 - 

36 

Maggot-like. 

Typically legless, 

thin and elongate. 

none none 

Modified head 

region. Reduced 

and poorly 

formed head, 

often retracted 

into the body. 

Mouth hooks 

(piercing and 

sucking) 

located at the 

pointed end of 

larva. 

Sawfly larvae have 

prolegs but no 

crochets. 

Variable 


Most are maggot-like. 

50 

81, 

130, 

140, 

169, 

179 

62, 

104, 

116, 

136, 

146 

Typically 

legless 

Developed head 

capsule. 

Variable 

mouthparts 

(difficult to see). 

Wasps, bees & ants 

O: Hymenoptera 

Grasping, 

sucking. 


Predatory with well-developed legs and large 

mouthparts relative to body size (head region 

comprised mostly of mouthparts). 

81 

119 - 

129 

95 - 

103 

Table 3.2 Key characters of invertebrates of agricultural importance – LARVAL FORMS 

Lacewings 

O: Neuroptera 

90 

6 none Tapering abdomen. 

Filamentous 

antennae. 

137 - 

138 

113 - 

114 

Large sickleshaped 

mandibles 

pointing forward. 


11 



Identification Keys 

Larval forms to main orders/families 

Can true legs be seen 

With legs 

Without any legs 

Without body 

(abdominal) prolegs, only 

3 pairs of ‘true’ legs 

‘True’ legs and 

additional body 

(abdominal) prolegs 

With typical 

hardened 

head capsule 

Modified head 

region. 

No distinct head 

capsule. 

Pointy head 

& mouthhooks 


Distinctly 

tapering body 

and head region 

comprised 

mostly of 

‘sickle-shaped’ 

mouthparts 

Lacewings 

(Neuroptera) 

Go to 

section 4: 

page 90 

See Ute Guide: 

SA pp.137-138; 

WA pp.113-114 

12 

Various body 

forms with 

head capsule 

and chewing 

mouthparts 

Beetle 

(Coleoptera) 

go to 

beetle larvae 

key 

section 3: 

page 13 

Some 

beneficial 

species 

Prolegs fleshy 

in appearance 

& without 

specialised 

hooks at base 

Sawflies 

(Hymenoptera) 

go to 

section 4: 

page 82 


Prolegs with 

specialised 

hooks at base & 

eyespots on side 

of head capsule 

Moths/ 

butterflies 

(Lepidoptera) 

go to 

moth larvae 

key section 3: 

page 14 

Weevil 

(Coleoptera) 

go to 

section 4: 

page 26 

Fly (Diptera) 

go to 

section 4: 

page 50 

Some 

beneficial 

species

Beetle larvae to main families 

Body characteristics 

‘C’-shaped. 

Swollen rear end 

(of abdomen) 

Predatory (campodeiform). 

Head oriented forward. 

Large mouthparts. 

Well-developed legs 

Usually long body. 

Head oriented downwards. 

Short functional legs 

(eruciform) 

Legless 

(apodous) 

Cockchafers/ dung 

beetle (Scarabidae) 

go to 

section 4: 

page 19 

See Ute Guide: 

SA pp. 62-64; 

WA pp. 46-48 

Hair-like 

projection on last 

body segment. 

Usually ground 

dwelling 

Carabidae 

go to 

section 4: 

page 31 

See Ute Guide 

SA p.139; 

WA p.115 

Usually grey/ 

black with yellow/ 

orange bandings 

across body. 

Above ground. 

Found on 

vegetation 

Ladybirds 

(Coccinellidae) 

go to 

section 4: 

page 29 

See Ute Guide 

SA pp.132-133; 

WA pp.106-107 

No such 

pattern 

Others 

e.g. rove 

beetles 

(Staphylinidae) 

Projection 

at end of 

abdomen 

Projection straight 

off the end of body 

(upper side). 

No anal proleg 

(under side) 

False wireworms 

(Tenebrionidae) 

go to section 4: 

page 24 

See Ute Guide 

SA pp. 53-54; 

WA p. 45 

Weevils 

go to 

section 4: 

page 26 

No projection at 

end of abdomen 

Other beetle 

families 

(non target) 

Projection off a serrated 

plate (upper side). 

Anal proleg present 

(under side) 

True wireworms 

or click beetles 

(Elateridae) 


page 22 

See Ute Guide 

SA p. 60 


13 


Moth/butterfly larvae to main families/species 

* size relates to mature larvae 

Number of body (abdominal) prolegs 

4 pairs of abdominal prolegs 

Anal prolegs vary in size 

Anal proleg 

Abdominal 

prolegs 

True legs 

1 or 2 pairs of abdominal prolegs 

Moves with looping action. 

Anal prolegs usually large 


Long and slender, 

found in soil 

tunnels 

Up to 35mm long*, 

forms chimneys 

on soil surface 

Pasture tunnel 

moth 

See Ute Guide 

SA p. 35 

*NOT in WA 

14 

Leaf 

rolling 

Lucerne leaf 

roller 

See Ute Guide 

SA p. 29; 

WA p. 31 

Diamondback 

moth 


page 13 

Up to 65mm long* 

Underground 

grass grub 

See Ute Guide 

SA p. 46 

Wriggles & 

suspends 

from thread 

when 

disturbed. 

Sparse 

coarse dark 

hairs over 

body 

Lime 

velvety 

green 

body 

densely 

covered 

with 

coarse 

dark hairs 

Extremely hairy 

body (covered 

in stout hairs) 

Grass anthelid 

See Ute Guide 

SA p. 45 

*NOT in WA 

Greenish in 

colour 

Cabbage white 

butterfly 

See Ute Guide 

SA p. 42; WA p. 35 

Two whitish 

stripes on back 

Grass blue 

butterfly 

See Ute Guide 

SA p. 44; 

WA p. 36 


* Small (< 30 mm). 

Slender or stout 

Distinctive stripes 

and webbing present 

Prefer warm 

periods 

Cabbage centre 

grub 

See Ute Guide 

SA p. 41; WA p. 32 

Wriggles when 

disturbed 

Weed web moth 

See Ute Guide 

SA p. 30; 

WA p. 29 

Body smooth or 

with few sparse 

hairs. 

* Large size 

(30-50 mm). 

Active at night 

Noctuidae 

Brown with raised areas 

around base of hairs. 

Found in underground 

tunnels 

Pasture webworm 

See Ute Guide 

SA p. 32; WA p. 24 

Feeds 

inside pod 

Lucerne seed 

web moth 


page 15

Legend 

Cereals 

Pulses 

Canola 

Mainly lucerne/pasture 

Polyphagous 

Yellow line running 

along back 

Predominantly 

green in colour. 

Spring pest 

Other loopers 

Brown pasture 

looper 

See Ute Guide 

SA p. 36; WA p. 28 

Chrysodeixis sp. 

See Ute Guide 

SA p. 37; WA p. 34 

Greasy and plump 

in appearance. 

No distinct markings 

and relatively few 

body hairs. 

Breathing holes 

(spiracles) dark on 

side of body 

Cutworms 

go to 

section 4: 

page 7 

See Ute Guide 

SA pp. 23-24; 

WA pp. 22-23 

Three stripes on 

neck (cervical 

shield) and running 

along body to tail 

Armyworms 

go to 

section 4: 

page 5 

See Ute Guide 

SA pp. 21-22; 

WA pp. 20-21 

8 th body (abdominal) 

segment sharply 

angled 

downward. 

Paler banding 

running along 

sides of body 

with a darker colour 

banding on top 

Native 

budworms 


page 11 

See Ute Guide 

SA pp.18-20; 

WA pp.17-19 

Body dark brown 

with yellow and 

reddish-orange 

markings 

Pasture day 

moth 

See Ute Guide 

SA p. 34; 

WA p. 33 

No such 

features as 

described 

Other noctuids 


15 


Beetles (adults) to main families/species 

Body shape 

Very distinct constriction 

between body parts – 

‘hot water bottle’ shape. 

Large mouthparts 

directed forward 

Carabid 

(Carabidae) 

go to 

section 4: 

page 31 

See Ute Guide 

SA p.139; 

WA p.115 

Round 

‘Pie’-dish 

Eastern false wireworm 


Go to section 4: page 24 

*In WA: pie-dish beetles not 

eastern false wireworm 

Points on base of thorax (pronotum). 

Flicks up and makes click sound 

when on its back 

Flat 

No points on 

ends of thorax 

Head region 

with a ‘snout’. 

Bent antennae 

on snout 

Weevils 

Go to 

section 4: 

page 26 


Spurs on legs. 

Clubbed 

antennae 

Cockchafers/ 

dung beetle 

(Scarabidae) 

go to 

section 4: 

page 19 

See Ute Guide 

SA pp. 63-64, 

150-152; 

WA pp. 46-48, 

125-126 

16 

Shiny black 

or bronze 

(metallic-like) 

Bronzed 

field beetle 


go to 

section 4: 

page 24 

See Ute Guide 

SA p. 56; 

WA p. 43 


or click beetles 

(Elateridae) 


page 22 

See Ute Guide 

SA p. 60 

Dull appearance. 

Dirty (often 

covered in soil) 

Vegetable 

beetle 


See Ute Guide 

SA p. 59; 

WA p. 45 


Domed 

shape 

Short wing-covers 

exposing rear body 

part (abdomen). 

Earwig-like appearance 

May be coloured 

orange/black patterns 

Ladybirds 



page 29 

See Ute Guide 

SA pp. 132-133; 

WA pp. 106-107 

Rove beetles 


No such 

patterns 

Others 

e.g. flea beetles 

(weed control 

agent) 

See Ute Guide 

SA p. 158; 

WA p. 133 

Typical length 

wing-covers 

(elytra) 

Grey false 

wireworm 


go to 

section 4: 

page 24 

See Ute Guide 

SA p. 57 

Other beetles 

(non target)

Moths (adults) to main families/species 

Mouthpart and head region appearance 

Legend 

Cereals 

Pulses 

Canola 

Mainly lucerne/pasture 

Polyphagous 

Beaked. 

Small moths (< 15 mm long) 

Not beaked. 

Large moths (> 30 mm long) 

Distinct stripe on 

side of wings 

More than one 

stripe on wings 

Non-descript 

brownish-toned 

scales 

Three diamond 

shapes created 

on wings at rest 

Lucerne seed 

web moth 


page 15 

See Ute Guide 

SA pp. 27-28 

WA p. 30 

Most butterflies have 

knob-like antennae 

See Ute Guide 

SA pp. 42-44 

WA pp. 35-36 

Pasture 

webworm 

See Ute Guide 

SA p. 32 

WA p. 24 

Other Pyralidae 

(non target) 

Diamondback 

moth 


page 13 

See Ute Guide 

SA pp. 25-26; 

WA pp. 26-27 

Stout body hairs and many 

markings & scales on wings 

in brown tones 

Noctuidae 

go to 

section 4: 

page 4 

Other 

description 

Others 

e.g. Grass anthelid 

See Ute Guide 

SA p. 45 


17 


Crop Damage 

Pest Identification Key – CEREALS 

Southern – Southern Ute Guide 

Western – Western Ute Guide 

* Relevant in S.E. Australia only **Relevant in WA only 


Damage to seedlings and young plants. 1 

Damage to advanced or ripening crop. 8 

1. Plants chewed above ground. 2 

No chewing evident above ground. 3 

2. Plants cut off leaving stumps close to the ground and/or large portions of leaves 4 

missing. 

Chewing but plants generally not cut off. 5 

3. Leaves bleached especially near tips. 6 

Plants yellowing, withering, stunted or dying. 7 

4. Leaves or plants cut off and lying on the ground or protruding from small holes next 

to plants; brown caterpillars (up to 15 mm long) with black heads, present in weblined 

tunnels; wheat or barley seeded into grassy pasture paddocks. 

Leaves or plants cut off and lying on the ground or protruding from small holes next 

to plants. Slender larvae, up to 35 mm long, construct silk-lined tunnels that 

protrude above ground to form chimneys. 


to plants. Larvae are brown with black and yellow marking, covered in tufts of stout 

hairs and can grow up to 50 mm in length. 

Leaves of young seedlings fed upon or damaged; in severe cases seedlings are 

ring-barked at ground level causing them to drop. Adults are 3-5 mm long, round 

and dull brown resembling small clods of dirt. 

Plants eaten close to or below ground level causing plant death and bare patches 

within the crop. 

Larvae emerge from tunnels with rain events to feed on foliage. Can cause bare 

patches in crops during late autumn and early winter. ‘C’ shaped larvae with six legs 

and a black to brown head capsule. 

Large portions of plants eaten and some leaves or plants cut off. Smooth, fat 

caterpillars up to 40 mm long usually found just under the soil surface and may curl 

up when disturbed. 

5. Green material removed in irregular patches from one surface of the leaf leaving 

white window-like areas; paddocks may appear white; presence of dumpy, wingless, 

greenish yellow insects, which spring off plants when disturbed. 

Leaves shredded or chewed, slimy trails. 

18 

Smooth, shiny brown animals with curved pincers at the end of the body. Damage 

irregular, often similar to slug damage, mostly in patches, when sown in heavy 

stubble. 

Grasshoppers and locusts. 

Minor leaf chewing; presence of dark brown to black caterpillars up to 60 mm long 

with two yellow spots near posterior end. 


Webworm 

Western p. 24 

Southern p. 32 


moth* 


Grass anthelid* 


Mandalotus weevil* 


Polyphrades weevil* 


Blackheaded 

pasture cockchafers* 


Cutworms 

Western p. 22 


Lucerne flea 

Western p. 70 


Slugs and snails 

Western pp. 71-74 

Southern pp. 90-95 

Earwigs 

Western p. 69 


Grasshoppers and 

locusts 



Pasture day moth 

Western p. 33 

Southern p. 34

6. Presence of tiny 8-legged (nymphs have 6 legs) velvety black or brown crawling 

creatures with orange-red legs, found on plants or on soil surface at the base of 

plants. 

7. Plants stunted and dying at emergence and up to tillering; chewing of seed and 

stem below ground; white legless larvae up to 7 mm long present near point of 

attack. 

Larvae attack swelling seeds just after sowing. They can bore into underground 

stems of seedlings causing them to wither into base of the plant tillers. Larvae are 

white and legless with a yellow head capsule and grow to 8 mm long. 

Plants stunted or dying; roots eaten; slow-moving, soft bodied insects usually in a ‘C’ 

shape, cream-coloured apart from head and visible gut contents; found near roots. 

Plants yellowing and withering; on light soils mostly on coastal plain; stems 

underground shredded; presence of elongated, cylindrical insects up to 75 mm 

long, first pair of legs adapted for digging. 

Larvae may attack germinating seeds below ground and germinating seedlings, 

causing plants to wither and die and bare patches in crops. Larvae grow up to 15-40 

mm; soft bodies and flattened in cross section with yellow-brown heads. 

8. Green and straw-coloured insect droppings like miniature square hay bales on 

ground; cereal heads on ground; some chewing of leaves and seed heads of weeds 

such as ryegrass. Smooth, fat caterpillars up to 40 mm long, with three stripes on 

collar behind head; found at base of plants or climbing plants. 

Seeds chewed but heads not severed; caterpillars up to 40 mm long, sparsely 

covered with small bumps and bristles, may be various shades of green, yellow, 

orange or brown; found on seed heads. 

Presence of many grey- green insects approx. 2 mm long, with or without wings, on 

upper portions of stem. If heavy infestations, plants stunted; sticky with secretions, 

possibly black mould growing on secretions; 

Damage in fine pale dots in wriggly or zigzag lines. Yellow to green, 3 mm long 

wedge-shaped sucking insects that jump sideways when disturbed. 

Redlegged earth 

mite 

Western p. 75 


Blue oat mite 

Western p. 76 


Balaustium mite 

Western p. 78 


Spotted vegetable 

weevil or Desiantha 

weevil 

Western p. 38 


Spinetailed weevil or 

cereal curculio* 


Cockchafers 

Western p. 46 

Southern pp. 61, 63 

African black beetle 

Western p. 48 


Sandgropers** 

Western p. 68 

Wireworms or click 

beetles* 


Armyworm 

Western p. 20 


Native budworm and 

related species 



Aphids 



Leafhoppers 

Western p. 61 



19 


Crop Damage 

Pest Identification Key - CANOLA 





20 

Damage to seedlings. 1 

Damage to flowering and podding canola. 2 

Insects contaminating harvested grain. 7 

1. Transparent windows and holes chewed in leaves. Dumpy, wingless, greenish-yellow 

insect-like creatures which spring off plants when disturbed. 

Leaf surface silvered or sucked. 3 

Cotyledons and young leaves chewed; seedlings or leaves cut off. 4 

Plants stunted or dying; roots eaten; slow-moving, soft bodied insects usually in a ‘C’ 

shape, cream coloured apart from head; found near roots. 

2. Flower heads attacked. 5 

Leaves or pods attacked. 6 

3. Surface tissue of leaves rasped by small mites with black or brown bodies and eight 

orange-red legs (tiny nymphs have 6 legs), giving leaves a silvered appearance. 


Lucerne flea 

Western p. 70 


WA cockchafers** 

Western p. 46 

Redlegged earth mite 

Western p. 75 


Blue oat mite 

Western p. 76 


Bryobia mite 

Western p. 77 



Western p. 78 

Southern p.101 

Pear-shaped insects sucking leaves, usually come from summer weeds. 

Rutherglen bug 

Western p. 49 


2 mm long cigar-shaped with and without wings – rarely cause damage. Thrips 

Western p. 63 


4. Presence of smooth, fat caterpillars up to 40 mm long just under soil surface. Cutworms 

Western p. 22 


Large sections of leaves chewed. In severe cases plants eaten down to ground level. 

Presence of dull grey-brown weevils (adults), 10 mm long or yellow-green larvae up 

to 15 mm long with flattened slug-like bodies. Larvae usually found in winter. 

Large sections of leaves chewed. In severe cases plants eaten down to ground level. 

Adult weevils chew cotyledons, leaves and stems and may eat plants down to 

ground level. 

Vegetable weevil 

adult and larvae 

Western p. 37 



or Desiantha weevil 

Western p. 38 


Small lucerne weevil 

Western p. 39 

(WA & NSW) 

Fullers rose weevil 

Western p. 42 


Feed on leaves of young seedlings; in severe cases seedlings are ring-barked at 

ground level causing them to drop. Adults are 3-5 mm long, round and dull brown 

resembling small clods of dirt. 

Areas of leaves chewed. Presence of black and cream striped caterpillars up to 30 

mm long that may walk with looping motion. 

Plants eaten at ground level. Shiny dark brown larvae (up 20 mm) with spines or 

pincers at the tail end; mainly when canola is sown in heavy stubble. 

Seedlings can be defoliated and die. Caterpillars feeding on leaves under a fine web, 

skeletonising leaves. Mostly in seasons with early autumn rainfall and warm weather. 


with two yellow spots near posterior end. Minor pest usually after pasture. 


Germinating seed or emerging seedlings are ring-barked and hypocotyl severed 

just below the surface. Large bare patches can seen a few weeks after sowing. 

Larvae up to 9 mm long, shiny brown-grey on top with paler undersides and two 

distinct upturned spines on last body segment. 

Seedlings chewed at or above ground level, ring-barking or completely cutting 

stems. Common adult species are 6-8 mm long, dark grey-black and often have a 

covering of soil. 

5. Flower stems covered with masses of small soft-bodied insects and black sticky 

mould. 

6. Holes chewed in leaves, surface of pods attacked by small, thin, green caterpillars, 

up to 10 mm long, that wriggle rapidly when touched and hang down on a thread. 

Round holes in pods; seeds eaten by large (up to 40 mm long), sparsely haired and 

often brightly coloured caterpillars. 

Leaves and flowers attacked, especially the basal leaves. Leaves can be combined 

together with webbing. Small creamish caterpillars with dark heads that may tunnel 

into growing points. 

Large, irregular holes chewed in leaves. Velvety green caterpillars (up to 30 mm). 

Pieces of leaves and stems chewed. Complete defoliation can occur in severe cases. 

Grasshoppers and locusts. 

7. Plant growth stunted and in severe cases heads can be distorted. Large numbers of 

narrow bodied, greyish-brown, flying insects, 3-4 mm long, contaminating 

harvested grain. 



Brown pasture 

looper 

Western p. 28 


Bronzed field beetle 

Western p. 43 


European earwigs 

Western p. 69 


Weed web moth 

Western p. 29 



Western p. 33 





Grey false 

wireworm* 


False wireworms or 

vegetable beetle 

adult 

Western p. 45 


Aphids 



Diamondback moth 

Western p. 26 


Native budworm 

Western p. 17 


Cabbage centre grub 

Western p. 32 


Cabbage white 

butterfly 

Western p. 35 


Grasshoppers 

& locusts 




Western p. 49 



21 


Crop Damage 

Pest Identification Key - PULSES 




FP=field peas, Lup=lupins, Len=lentils, F=faba beans, C=chickpeas. Not applicable for soybeans. 


1. Seedlings damaged. 1 

22 

Areas of green tissue removed from leaves with surface tissue remaining like 

windows; presence of dumpy, green, wingless insects that spring off plants when 

disturbed. 

FP, Lup, Len, F 

Leaf surface silvered, sucked and withered. 2 

Plants dying without obvious above ground symptoms. 3 

Whole plants or parts of cotyledons and leaves eaten or cut off. 4 

Damage later to leaves, flowers or pods. 5 

2. Surface tissue of leaves rasped by small mites with black or brown bodies and eight 


FP, Lup, Len, F 

Plant growth stunted. Pear-shaped insects sucking leaves, usually come from 

summer weeds. 

All pulses. 

3. Plants stunted or dying; roots eaten; slow-moving, soft bodied insects usually in a ‘C’ 

shape, cream coloured apart from head and visible gut contents; found near roots. 

All pulses. 

Plants yellowing and withering; on light soils mostly on coastal plain; stems 

underground shredded; presence of elongate, cylindrical insects up to 75 mm long, 

first pair of legs adapted for digging, head and front of thorax reddish brown and 

the remainder of the body a cream colour. 

All pulses. 

Roots rotting, cream grubs tunnelling in stem, worst in previous year’s stubble. 

FP, Lup 

4. Some plants cut off at ground level; cotyledons and leaves chewed; fat, smooth 

caterpillars up to 40 mm long under soil surface near plants. 

All pulses. 

Leaves chewed but mostly at edges of crop; 30 mm long caterpillars with dark stripe 

surrounded by lighter areas down the back. 

All pulses. 

Caterpillars feed on leaves under a fine web, skeletonising leaves. Seedlings can be 

defoliated and die. Mostly in seasons with early autumn rainfall and warm weather. 

All pulses. 


Lucerne flea 

Western p. 70 


Redlegged earth 

mite 

Western p. 75 


Blue oat mite 

Western p. 76 


Bryobia mite 

Western p. 77 



Western p. 78 



Western p. 49 


WA Cockchafers** 

Western p. 46 

Sandgropers** 

Western p. 68 

Onion maggot 

Western p. 62 


Cutworms 

Western p. 22 


Brown pasture looper 

Western p .28 


Weed web moth 

Western p. 29 



All pulses. 

Chewing on cotyledons, leaves and stems. Plants may be eaten down to ground 

level under high pest pressure. Presence of insects 3 - 12 mm long with prominent 

weevil snout, that may hide during day and be uncovered under rocks, soil clods or 

wood. 

All pulses. 

Smooth shiny brown animals with curved pincers at the end of the body. Mainly 

when sown in heavy stubble. 

All pulses. 

5. Flower stems covered with masses of small soft-bodied insects and black sticky 

mould. 

All pulses, rarely seen on chickpeas. 





Western p. 37 



or Desiantha weevil 

Western p. 38 




European earwigs 

Western p. 69 


Aphids 



Some leaves and flowers chewed; holes in pods; caterpillars up to 40 mm long 

sparsely covered with bumps and hairs, often brightly coloured in greens, browns 

and shades of orange and usually with black stripes along dorsal surface. 

All pulses. 

Cream to green caterpillars with red brown head and red stripes along the back 

feeding on plant with a web, or inside pods. 

All pulses. 

No evidence of leaf damage to plants, the presence of small, bright orange oval 

eggs on developing pods. 

FP 

Chewing evident. Grasshoppers and locusts. 

All pulses. 


Western p. 17 


Lucerne seed web 

moth 

Western p. 30 


Pea weevil 

Western p. 44 


Grasshoppers and 

locusts 




23 


Crop Damage 

Pest Identification Key - ANNUAL PASTURES AND LUCERNE 





24 

Seedlings or young plants damaged. 1 

Damage to leaves, flowers or seed formation. 5 

1. Areas of green tissue removed from leaves with surface tissue remaining like 

windows; dumpy, wingless, greenish-yellow insects that spring off plants when 

disturbed. Broad-leafed plants most commonly affected. 

Leaf surface silvered, sucked and withered. 2 

Plants dying without obvious symptoms. 3 

Whole plants or parts of cotyledons and leaves eaten or cut off. 4 

2. Surface tissue of leaves rasped by small mites with black or dark bodies and eight 


Plant growth stunted. In severe cases, stands flower poorly and buds are aborted. 

Pale green flying insects and pear-shaped larvae sucking leaves in spring and 

summer. 

Plant growth stunted. Pear-shaped (nymph) crawling insects or elongated dark 

winged insects (adults 4 mm long) sucking leaves. May be present in summer, 

autumn and or spring. 

3. Plants stunted or dying; roots eaten; slow-moving, soft bodied insects usually in a 

‘C’-shape, cream coloured apart from head and visible gut contents; found near 

roots. Note, these cockchafers do not feed on foliage. 

4. Some plants cut off at ground level; cotyledons and leaves chewed; fat, smooth 

night feeding caterpillars up to 40 mm long often found under soil surface near 

damaged plants. Or brown/black caterpillars that may be found feeding above 

ground during the day. 

Lucerne, medics, sub clovers and some other plants stunted or dying. May have 

yellow or reddened appearance. Nodules and roots eaten by pale or cream 

coloured legless weevil grubs, found near roots below ground. 

Weevil adults chew bits out of leaves leaving scalloped edges. 


Lucerne flea 

Western p. 70 



Western p. 75 


Blue oat mite 

Western p. 76 


Bryobia mite 

Western p. 77 



Western p. 78 


Green mirid 

Western p. 51 



(nymphs) 

Western p. 49 


Cockchafers 

(Not including 

Blackheaded 

cockchafers) 



Cutworms 

Western p. 22 


Sitona weevil 

Western p. 40 


Small lucerne weevil** 

Western p. 39 (& NSW) 

White fringed weevil 

Western p. 41 


Fullers rose weevil 

Western p. 42 


Grass leaves or plants cut off and lying on the ground or leaves protruding from 

small holes next to plants; brown caterpillars, up to 15 mm long, with black heads 

present in web-lined tunnels. 

Leaves chewed but mostly at edges of crop; 30 mm long caterpillars with dark stripe 

surrounded by lighter areas down the back. 

Leaves shredded or chewed, slimy trails may also be seen. Pest more often seen 

after rain with moist leaf surfaces. 


with two yellow spots near posterior end. Minor pest usually feeding on broadleafed 

weeds e.g. capeweed. 


to plants; Slender larvae, up to 35 mm long, construct silk-lined tunnels that 

protrude above ground to form chimneys. 

Larvae emerge from tunnels with rain events to feed on foliage. Can cause bare 

patches in crops during late autumn and early winter. ‘C’ shaped larvae with six legs 

and a black to brown head capsule. 


to plants. Larvae are brown with black and yellow markings; covered in stout hairs 

and can grow up to 50 mm in length. 

5. Flower stems covered with masses of small soft-bodied insects and sometimes black 

sticky mould. Susceptibility varies between legume species and medic varieties. 

Aphids may occasionally become a pest in early established pasture and lucerne 

stands with warm temperatures. 

Some leaves and flowers chewed; holes in podding legumes; caterpillars up to 40 

mm long sparsely covered with bumps and hairs, often brightly coloured in greens, 

browns and shades of orange and usually with black stripes along their backs. 

Serradellas are often affected. 

Pods are chewed out resulting in reduced yield. Cream to green caterpillars with 

red-brown heads and red stripes along the back, feeding on plants or inside pods, 

often with fine silken webbing nearby. 

Leaves at the tips of growing points are rolled and can be skeletonised. Pale to green 

caterpillars which may drop from plants on a silken thread. 

Pieces of leaves and stems chewed. Complete defoliation can occur in severe cases. 

Grasshoppers and locusts present. 

Leaves and growing points are chewed. Ten millimetre green slug-like larvae with a 

white line down each side and a dense covering of short hairs; mostly attacks leaves 

with skeletonising type damage. 


Western p. 24 


Brown pasture 

looper 

Western p. 28 






Western p. 33 



moth* 


Blackheaded 

pasture cockchafer* 


Grass anthelid* 


Aphids 




Western p. 17 


Lucerne seed 

web moth 

Western p. 30 


Lucerne leafroller 

Western p. 31 


Grasshoppers & 

locusts 



Grass blue butterfly 

Western p. 36 



25 



26 

SECTION 3 IMPORTANT INSECT GROUPS AND IDENTIFICATION KEYS

Common Pest, Beneficial 

and Exotic Species 

4 

Common 

Species

SECTION 4 

Common Pest, Beneficial 

and Exotic Species 

Moths & Butterflies ................................................. 2 

Armyworms ............................................................4 

Cutworms ..............................................................7 

Budworms ............................................................11 

Diamondback moth ...................................................13 

Lucerne seed web moth ...............................................15 

Beetles ........................................................... 17 

Cockchafers ...........................................................19 

True wireworms ...................................................... 22 

False wireworms . ..................................................... 24 

Weevils . .............................................................. 26 

Ladybird beetles ..................................................... 29 

Carabid beetles (or Ground beetles) ....................................31 

Bugs .............................................................. 33 

Figure 4.1 An example of an aphid lifecycle (Aphis sp.) . .................. 35 

Figure 4.2 Persistent versus non-persistent transmission of viruses . ....... 36 

Table 4.1 Some aphids known to transmit viruses in pulse crops .......... 36 

Cereal aphids - Corn aphid, Oat aphid & Russian wheat aphid .......... 37 

Canola aphids - Cabbage aphid, Turnip aphid & Green peach aphid .....41 

Pulse aphids - Blue green aphid, Pea aphid, Cow-pea aphid & 

Green peach aphid ..................................... 43 

Sunn pest ............................................................ 45 

Damsel bugs (or Nabids) .............................................. 47 

Predatory bugs - Predatory shield bugs and Assassin bugs ............. 49 

Flies .............................................................. 50 

Gall midges or Gall gnats - Hessian fly & Barley stem gall midge ........ 52 

Exotic leaf miners . .................................................... 54 

Hoverflies ............................................................ 57 

Earwigs ........................................................... 59 

European earwig & Native earwigs .................................... 60 

Springtails ........................................................ 63 

Lucerne flea .......................................................... 63 

Slugs & Snails ..................................................... 65 

Round snails - White Italian snail & Vineyard or common snail .......... 66 

Conical snails - Small pointed snail & Pointed snail ..................... 68 

Slugs - Reticulated or grey field slug & Black-keeled slug ............... 70 

Mites ............................................................. 72 

Red legged earth mite, Blue oat mite, Balaustium mite & 

Bryobia mite or Clover mite ........................................... 72 

Figure 4.3 Typical lifecycle of redlegged earth mites in southern Australia . 75 

Predatory Mites ...................................................... 80 

Wasps, Bees & Ants ................................................ 81 

Wheat stem sawfly & European wheat stem sawfly .................... 82 

Wasp parasitoids ..................................................... 84 

Egg parasitoids ....................................................... 87 

Bees as pollinators ................................................... 89 

Lacewings & Antlions .............................................. 90 

Green lacewings & Brown lacewings ................................. 90 

Spiders ........................................................... 92 

More information ................................................. 93 

Legend 

Crop type 

Cereals 

Canola (& Brassicas) 

Pulses & legumes 

Pasture 

Monitoring type 

Observation 

Sweep net 

Yellow sticky trap 

Yellow pan trap 

Digging 

Pitfall trap 

Pheromone trap 

Light trap 

Insect status 

pest = blue 

beneficial = green 

biosecurity = red 

F = Family 

SF = Superfamily 

Scale bar 

10 mm 20 30 

adult 

Maximum size shown 

for larva and adult 

SECTION 4 COMMON Pest, Beneficial AND EXOTIC Species 

1 


MOTHS & BUTTERFLIES (Order Lepidoptera) 

Lepidoptera - scale (lepi); covering wing (ptera) 


In Australia there are about 20,800 lepidopteran species 

divided into over 80 families. 

Main characteristics 

Larva 

Larvae or grubs are generally elongated in form, 

with three pairs of true (thoracic) legs directly 

behind the head. Larvae have a well-developed and 

hardened (sclerotised) head capsule and chewing 

(mandibulate) mouthparts. On the front of the head 

is a groove (suture) shaped like an inverted ‘V’ and a second 

suture (adfrontal) just under the ‘V’. Most have ventral and 

anal prolegs as well as crochets (small hooks) on the base 

of the prolegs. These hooks help the larva hold on to the 

surface. Most larvae feed on foliage or stored products. 

Adult (moths) 

Adults have two pairs of large membranous wings 

that are completely covered with scales in regular, 

overlapping rows on both surfaces. They have hairy 

Lepidopteran larva 

Anal 

proleg 

with 

crotchets 

2 

Eyespots 

1 st abdominal segment 

SECTION 4 COMMON Pest, Beneficial and exotic Species 

Side view of head 

Abdominal 

prolegs with 

crochets 

bodies, a small head covered in scales and large eyes. 

Adults have a long, thin, coiled sucking tube (proboscis) 

which they use to feed on liquid sugar sources. They have 

multi-segmented antennae (comb-like in male moths, 

thread-like in female moths). Moths usually shelter by 

day and fly at night, unlike butterflies, which are mostly 

active during the day. 

Lifecycle 

Complete metamorphosis. Depending on the species, 

females may lay a few or tens of thousands of eggs 

(several hundred is typical). Larvae develop through 4-7 

instars (taking a few weeks or up to a few months) before 

pupating. Pupation can occur on vegetation, in the soil 

or leaf litter and even inside wood. Many lepidopterans 

have one or two generations per year, some breed 

continuously and others may take years to develop (e.g. 

Cossidae). 

Spiracle 

(breathing 

hole) 

Cervical (neck) shield 

‘True’ leg 

Various crochet (hook) patterns at the base 

of all abdominal and anal prolegs-soles on feet 

Front view of head 

Hardened 

(sclerotised) 

head capsule 

with 

chewing 

mouthparts 

Source: Modified from Goodyer (1978) and CSIRO (1991)

Groups (families) relevant to broadacre 

cropping 

Cutworms, armyworms and native budworm 

(F: Noctuidae): The larvae of this family are among the most 

damaging crop pests and are covered in this section on 

page 4-12. 

Looper caterpillars (F: Geometridae): Larvae have 

a reduced number of prolegs (i.e. two or three pairs 

of prolegs towards their rear end) and move by a 

characteristic looping action when walking. The brown 

pasture looper, Ciampa arietaria is an example. This 

looper undergoes one generation per year with the 

moths flying in autumn. Refer to Ute Guides, Southern 

(p. 36)/Western (p. 28) for more detail. Loopers are not 

just confined to the Geometridae family. A minor spring 

pest of canola and pulses, Chrysodeixis spp. (Noctuidae) 

also move with a characteristic looping action and have 

a reduced number of prolegs. For further information, 

refer to Ute Guides, Southern (p. 37)/ Western (p. 34). 

Diamondback moth (F: Plutellidae): This is a pest of 

canola and is covered in this section on page 13. 

Grass moths (F: Pyralidae): These are generally small 

moths (most

ARMYWORMS, CUTWORMS, BUDWORMS & SEMI-LOOPERS 

Lepidoptera: Noctuidae 

Key noctuid characteristics and biology 

Larvae 

• have four pairs of abdominal prolegs; 

• have anal prolegs; 

• crochet (soles of prolegs) arrangement is a row on one 

side (mesoseries); 

• usually have a stripe on cervical shield; 

• usually smooth, lacking obvious dense hairs; 

• can vary widely in colour and this variation sometimes 

depends on the food source. Larvae are often green, 

brown or yellow in colour and striped longitudinally; 

• mostly feed at night on a variety of crops. 

Adults 

• are generally dull coloured moths but some have 

metallic-looking markings on their wings; 

• generally have stout bodies covered in dense long 

scales; 

• feed on nectar from flowers; 

• mainly fly at night. 

Many species are able to migrate long distances aided 

by wind currents. This enables them to exploit abundant 

plant growth after rain. 

Most fully mature noctuid larvae burrow into the soil 

to pupate, although a few species pupate in a sparse 

cocoon under a leaf of the host plant. Depending on 

the species, pupation can take place over a short or long 

time before moths emerge. 


There are many noctuid species that lack some 

abdominal prolegs and these are known as semiloopers. 

They loop their bodies when moving and are 

often mistaken for a ‘true’ looper (Geometridae family). 

Semi-looper species are not covered in this manual. 

4 

Noctuidae larva 

Anal 

prolegs 

Spiracle 


1st abdominal segment 

Abdominal 

prolegs 

True legs 

Body hair 

Crochet (hook) arrangement 

meso-series to one side. 

Armyworms, cutworms and 

budworms have this pattern 

on the ‘soles of their feet’ 

Cervical shield 

Cervical stripe 

Head 

Round dark coloured base 

Source: Modified from Goodyer (1978)

ARMYWORMS Lepidoptera: Noctuidae 

Common armyworm (Leucania convecta), Southern armyworm or barley grub 

(Persectania ewingii), Inland armyworm (Persectania dyscrita) and Sugarcane 

armyworm (Leucania stenographa - WA only) 

Distinguishing characteristics/description 

larva 

adult 

Larva 

10 mm 

20 

30 40 50 

wingspan 

Three stripes on 

cervical shield and 

along entire 

body to tail 

Head 

Cervical shield 

(neck) 

4 

abdominal 

prolegs 

Last 

abdominal 

segment 

Source: Modified 

from Goodyer (1978) 

Adult 

Common armyworm 

Southern armyworm 

Inland armyworm 

Forewing: dull red-brown 

or yellow-brown speckled 

with small black dots and a 

small white centred 

mark. Hindwing: grey 

Forewing: reddish-brown 

and streaked with white 

on edges. Silvery fish 

(or submarine) shape in 

centre is closed. 

Hindwing: dark grey 

Forewing: reddish-brown and 

streaked with white on edges. 

Silvery fish (or submarine) 

shape is open 

(looks like two dots). 

Hindwing: dark grey 


5 


Larvae are mostly nocturnal. They burrow into the 

soil or hide under leaf litter during the day. They may 

sometimes be found feeding during the day on the 

leaves, stems and heads of cereal crops. 

Confused with/similar to 

Larvae of these main pest species are very similar to each 

other and distinguishing characters are obscure. They can 

be distinguished by the position of the breathing holes 

(spiracles) in relation to a band on the side of the body. 

Distribution, pest status and risk period 

Armyworm populations are often sporadic. They may 

build up in an area over time in response to favourable 

seasonal conditions or suddenly migrate into an area on 

prevailing winds from a remote location. 

When in large numbers, armyworm larvae can eat their 

way across a paddock like an army on the march. This 

is occasionally seen in establishing pastures in autumn. 

Monitoring/sampling 

Assessing the numbers of armyworms in a cereal crop 

can be difficult as their movements will vary with 

weather conditions and feeding preference. Sometimes 

they are found sheltering on the ground and under leaf 

litter, while on other days they will be high up on the 

plants or on the heads, and easily picked up using sweep 

nets. They often prefer to feed on ryegrass if it is present. 

Armyworms may be confined to only small portions of a 

crop. Several different locations within the crop should 

be checked for caterpillar numbers before deciding on 

any control measures. 


Armyworms can be in damaging numbers at any time of 

year if growing conditions allow. They are occasionally a 

pest on seedling crops and pastures in autumn but more 

commonly cause damage to maturing cereal crops. 

There can be 3-4 generations per year. 

Crops attacked/host range 

Armyworms are pests of cereal crops and pastures. They 

prefer to feed on ryegrass and will often feed until it 

is depleted before turning to other grasses or cereals. 

Larvae do not feed on broad leaf and legume crops. 

Barley is the most susceptible cereal crop. Wheat crops 

are less frequently attacked. 

Damage symptoms 

Younger larvae feed on cereal or grass leaves. They are 

at their most damaging when large larvae (25-40 mm) 

attack barley crops nearing maturity in late spring. 

As barley matures, part of the stem often remains green 

and is appetising to larvae after other plant parts have 

dried. The caterpillars chew through the stem causing 

heads to fall to the ground. In oat crops, the larvae bite 

off pieces of the panicle, causing grain to fall. 

6 


A suggested monitoring procedure is to: 

• look for signs of caterpillar droppings and damaged 

ryegrass heads; 

• look for damage on crop foliage; 

• shake the plants and look for caterpillars on the plants 

and on the ground. Search leaf litter between rows; 

• check frequently for the first signs of head-lopping 

in barley. 

Management options 

Some threshold guidelines available indicate spraying 

may be worth considering if 3 larvae/m 2 are present in 

barley crops that are still more than a week away from 

harvest, and 10 larvae/m 2 in other cereals. If the barley 

crop is almost dry, continue checking daily until fully 

mature, as sudden head-lopping requires immediate 

action. 

Biological Cultural Chemical 

Naturally occurring biological 

control agents are important in 

keeping armyworm populations 

below damaging levels in some 

years. These include parasitic flies 

and wasps, predatory beetles and 

diseases. 

Ute Guides, Southern (pp. 21-22)/Western (pp. 20-21). 

Use of herbicide or grazing to control 

weedy paddocks several weeks before 

sowing pastures or cereals will starve 

out caterpillars. 

Desiccating or swathing crops close to 

harvest may have the added benefit of 

minimising armyworm damage. 

Registered rates of synthetic 

pyrethroids are usually adequate 

for control. Increased spray volumes 

may be required in high-yielding 

bulky crops.

CUTWORMS Lepidoptera: Noctuidae 

Common cutworm or Bogong moth (Agrotis infusa), Brown or Pink cutworm 

(Agrotis munda) and Black cutworm (Agrotis ipsilon) 


10 mm 20 30 40 50 

larva 

adult 

wingspan 

No distinct lines on sides 

of body and subtle 

longitudinal line may be 

present along midline upper 

(dorsal) surface 

Larva 

8 th abdominal 

segment spiracle 

(breathing hole) 

Spiracles 

Dark head region 

4 abdominal 

prolegs 

Adult 

Stout 

bodies 

covered 

with 

dense 

scales 

Plump, smooth, and greasy 

appearance with relatively 

few stout hairs with dark 

pigmentation at 

their base 

Pink cutworm 

Black cutworm 

Bogong moth 

4 abdominal 

prolegs 

Cervical shield stripe 

can be present or 

absent 

Forewing: brownish with darker 

markings and streaks. 

Large inner light mark and 

darker outer mark. 

Hindwing: pale with 

dark edging 

Forewing: brown or grey-black. 

Dark arrow-mark streak broken 

by 2 dark ringed dots. Outer 

margin is streaked. 


darker edging 

Forewing: Dark brown or grey 

black. Dark arrow-mark streak 

broken by 2 light dots. 


darker edging 


7 



Adult colouration can be highly variable. 

Larvae are plump and smooth (greasy appearance) and 

will vary in colour depending on the instar and species. 

The larva of the pink cutworm is usually found in sandy 

soils and is grey-green with a pink tinge. The larva of the 

bogong moth is dark grey. 

Larvae are mostly nocturnal. They generally hide under 

the soil surface or litter and come out at night to feed, 

although at least one species may be found feeding 

above ground during the day. The caterpillars often curl 

up when disturbed. 


Larvae of these three main pest species are very similar 

to each other and distinguishing characters are obscure. 

They may also be confused with the biosecurity threat, 

the turnip moth (Agrotis segetum). 


Widely distributed with various other species. They are 

most damaging when caterpillars transfer from summer 

and autmun weeds onto newly emerged seedlings. They 

can have several generations per year. 


Cutworms will attack all crops and pasture plants 

(polyphagous) but are at their most damaging when they 

feed on newly-emerged cereal and pasture seedlings. 

8 



Large caterpillars will chew through or cut off the stems 

of young seedlings, hence the name cutworm. 

Whole paddocks of cereal or legume seedlings may be 

destroyed or severely thinned in the presence of high 

populations of large cutworm larvae early in the season. 

Larvae feed at or near ground level. When small, the 

larvae feed on the surface tissues of the tender foliage. 

This surface feeding may be confused with damage 

caused by lucerne flea or other small caterpillars. 


A suggested monitoring procedure is to: 

• look for patches of newly emerged crops with 

seedlings cut off; 

• scratch the soil layers close to recently damaged 

seedlings to reveal hidden larvae; 

• use a shovel to sample for grubs by scraping off the 

top 50mm of soil near freshly damaged plants. Flick 

the soil off the shovel so that it spreads in a thin layer, 

revealing the grubs. Do this in several places near 

damaged areas; 

• use a backpack sprayer to spray out small areas. 

Check the following morning for dead grubs which 

can be found on the soil surface. 


These are not regular pests, but large areas may be 

affected in some seasons. Extensive damage can occur 

if more than 3 larvae/m 2 are found. Spot spraying, or 

spraying a 20 metre buffer around the infestation, may 

provide adequate control. Spraying in the evening is 

likely to be more effective. 


Naturally occurring insect fungal 

diseases are successful in some 

seasons. Wasp and fly parasites are 

also very active in preventing more 

frequent and serious outbreaks. 

Parasites include the orange and 

two-toned caterpillar parasite, 

(Heteropelma scaposum) and the 

orchid dupe (Lissopimpla excelsa). 

Refer to Southern (pp. 120 & 122)/ 

Western (pp. 96-97) Ute Guides for 

more detail. 

Ute Guides, Southern (p.23, 24)/Western(p22, 23) 

Prolonged autumn green feed in 

many areas may allow larvae to 

develop to a large size by the time 

crops emerge. Early control of this 

plant material (green bridge) using 

a herbicide to create a complete 

brown-out for two weeks preplanting, 

will minimise larval survival. 

Cutworm caterpillars are usually 

easy to control with label rates of 

synthetic pyrethroid chemicals 

(refer to currently registered 

products).

Cutworm - Turnip moth (Agrotis segetum) 

BIOSECURITY THREAT 

NOT PRESENT IN AUSTRALIA 


larva 

adult 

10 mm 

20 

30 40 50 

wingspan 

4 abdominal prolegs 

Larva 

Greyish-brown in colour with 

a greasy appearance and a reddish 

or brownish-black head capsule 

Two broad and light longitudinal 

bands running along the 

midline (that can have a very 

thin white line cutting through) 

Narrow dark 

band with white 

line inside 

Broad light 

bands 

On each body (abdominal) 

segment, there are 4 black 

spots each bearing a small bristle 

Adult 

All cutworm caterpillars are plump and smooth (greasy 

appearance), and can vary in colour depending on the 

instar. 

Larvae are mostly nocturnal and often burrow during 

the day, hiding under the soil surface or litter. 

More than one generation per year. 


Turnip moth can be confused with other cutworms 

present in Australia. 

Uniform 

circle 

Hindwings: grey in female; 

white/silver with light 

purple tinge in males 

Stout bodies covered in 

dense long scales. 

Antennae: threadlike in females; 

feather-shaped in males 

Distribution and potential spread 

Europe, Africa, northern Asia including China. Turnip 

moths are strong flyers and dispersal is aided by wind 

currents. This species is not known to migrate over large 

distances. Incursion and dispersal could occur through 

the transportation of plant and soil material. 


Thin black 

border on wing 

periphery 

Kidney-shaped 

marking 

Turnip moth is a highly polyphagous pest in its current 

distribution, attacking wheat, barley, oats, brassicas, 

vegetables and weeds. 


9 



All cutworm larvae are most damaging when they feed 

on newly emerged seedlings and cause plant death. 

Large caterpillars will chew through or cut off the stems 

of young seedlings. When small, the larvae feed on 

the surface tissues of the foliage resulting in very small 

round ‘window panes’. This surface feeding may be 

confused with damage caused by lucerne flea or other 

small caterpillars. 

Reporting protocol 

A rapid response to detection of potential exotic 

pests can be the key to containment, eradication or 

management. 

Surveillance 

Turnip moth is likely to be misidentified as other cutworm 

species already present in Australia due to the difficulty 

of distinguishing between species. 

Early detection of plant pests can greatly increase 

the chance of successful eradication and reduce 

the cost and social impact of an incursion. 

Incorporate surveillance for exotic pests when 

undertaking routine crop monitoring and other crop 

detection and measurement activities. 

If you see anything unusual, call the Exotic Plant Pest 

Hotline on 1800 084 881. 

Speak to your department of primary industries or 

department of agriculture before sending any samples. 

It is essential that the correct sampling protocol is 

followed including packaging, handling and transport to 

the laboratory assigned for diagnosis. Incorrect handling 

could spread the pest further or render the samples unfit 

for identification. 

Stop the movement of people, vehicles and equipment 

in the detected area until a confirmation can be made. 

More information 

Plant Health Australia website 

www.planthealthaustralia.com.au/biosecurity/grains 


10 

SECTION 4 COMMON Pest, Beneficial and exotic Species

BUDWORMS Lepidoptera: Noctuidae 

Native budworm (Helicoverpa punctigera), Lesser budworm (Heliothis punctifera) and 

Corn earworm/cotton bollworm (Helicoverpa armigera) 


larva 

10 mm 

20 

30 40 50 

adult 

Larva 

wingspan 

Stout hair over the body 

with pigmentation 

around the base 

Rear portion of body 

sharply angled downward 

from 8 th abdominal 

segment 

Often broad lighter coloured 

strip along each side of the 

body with a darker strip 

down centre 

Dark spiracles in 

lighter colour 

band 

Source: Modified from Goodyer (1978) 

Adult 

Black hairs 

around 

head 

region 

Native budworm Corn earworm Lesser budworm 

Male 

Female 

White hairs 

around head 

region 

Saddle 

Male 

Female 

White 

hairs over 

whole 

body 

Male 

Female 


11 



Armyworm and cutworm in general appearance and size. 

All budworms are at their most damaging when they 

feed on the fruiting parts and seeds of plants. 



Native budworm: Occurs in most years and often 

migrates into agricultural areas from nearby pastoral 

areas. It is a native species and is usually easily controlled 

with insecticides. 

Lesser budworm: Infrequent pest. 

Corn earworm/cotton bollworm: Rarely found in 

dryland broadacre crops but often associated with 

irrigated and/or horticultural crops. This pest is known 

to develop strong resistance to insecticides and can be 

difficult to control. 


Native budworm: Broad leaf and legume crops such as 

field pea, faba bean, lentil, chickpea, lupin and canola. 

Pastures such as pasture serradalla, lucerne, annual 

medic and clovers. Only occasionally feeds on cereals 

and some grasses. 

Lesser budworm: Wide host range, will feed on both 

broad leaf grasses and cereals. 

Corn earworm/cotton bollworm: Wide host range. 


Holes or chewing damage may be seen on pods and/or 

seed heads. Grubs may be seen occasionally. 

12 


Losses attributed to budworms come from direct weight 

loss through seeds being wholly or partly eaten. Grain 

quality may also be downgraded through unacceptable 

levels of chewed grain. 


The quickest and easiest method to sample most crops 

is sweep netting. Multiples of 10 sweeps should be taken 

in several parts of the crop and larval numbers averaged. 


Caterpillars eat increasing quantities of seed and plant 

material as they grow. The last two growth stages (5 th 

& 6 th instar) account for over 90% of their total grain 

consumption. 

Field pea, chickpea, lentil and faba bean crops are 

very susceptible to all sizes of native budworm 

caterpillars during the formation and development of 

pods. Small caterpillars can enter emerging pods and 

damage developing seed while larger caterpillars may 

devour the entire pod contents. 

Narrow-leafed lupin and canola crops will not be 

damaged by native budworm until they are close to 

maturity and leaf fall commences. 

For lesser budworm, the same principles as native 

budworm can be applied. 

For corn earworm, please refer to DEEDI website. 


Naturally-occurring insect fungal 

diseases and viruses can be very 

successful in some seasons. 

Predatory shield bugs, damsel bugs 

and fly parasites may also be active 

in preventing serious outbreaks. 

Parasites include the orange and 

two-toned caterpillar parasite 

(Heteropelma scaposum) and the 

orchid dupe (Lissopimpla excelsa). 

Refer to Southern (pp. 120 & 122) 

and Western (pp. 96-97) Ute Guides 

for more detail. 


Swathing canola or desiccating 

pulse crops such as field peas may 

be an option to advance the drying 

of crops when small/medium size 

larvae are present. 

For corn earworm refer to DEEDI 

website. 

Native budworm and lesser budworm 

are easily controlled by synthetic 

pyrethroids. 

Corn earworm are known to have 

insecticide resistant populations. 

Use of Bt and NPV biological 

insecticides are important IPM 

options.

Lepidoptera: Plutellidae 

Diamondback moth - DBM (Plutella xylostella) 


larva 

10 mm 20 30 40 50 

Larva 

Head capsule 

lightens as matures 

adult 

Adult 

Beak-like 

mouthpart 

Larvae slightly tapered at 

each end. Pale yellowish 

green in colour 

‘Diamond’- shape 

pattern on wings 

at rest 

Body covered in 

coarse black hairs 

Mesh-like pupal casing 

Leaf mine of 1 st larval instar 

Eggs are pale yellow, oval and about 0.5 mm in length. 

Eggs are laid singularly or in clusters along the leaf 

margins. 

Larvae develop through four instars. The first two instars 

have a dark head, but the first instar is not visible as it lives 

and feeds inside leaf tissue (its presence is indicated by 

a leaf mine). Larvae wriggle vigourously when disturbed 

and often drop from the plant on a silken thread. 

The pupal casing is mesh-like in appearance and the 

pupa inside is cream-green initially, but darkens before 

the adult emerges. 

Four abdominal 

prolegs 

Nearly 

complete crochet 

arrangement at 

base of prolegs 


Anal prolegs 

Diamondback moth (DBM) larvae can be confused 

with young cabbage white butterfly (Pieris rapae) and 

cabbage centre grub (Hellula sp.) larvae. 


DBM is a worldwide pest with a high propensity 

to evolve insecticide resistance. DBM is widely 

distributed in southern Australia. 

DBM has no diapause phase in Australia and has 

overlapping generations. All life stages can be present 

at any one time. Adults are active flyers but usually do 

not move far within a crop. 


13 


They are capable of long distance migration on prevailing 

winds, particularly when host material has died off. 

Weather conditions can impact dramatically on DBM 

populations. Development is faster in warm weather 

and slower in cool weather. For example, at 15 °C the life 

cycle takes approximately 36 days to complete, but at 

28°C it takes approximately 11 days to complete. 


DBM feeds on canola and all Brassica plants, including 

weeds. 

The availability of Brassica host plants can influence 

outbreaks. Summer rainfall can also provide a green 

bridge of summer weeds. 

DBM adults migrate from summer weed sources into 

canola crops in autumn and winter. Significant rainfall 

events (greater than 8 mm) can reduce larval abundance 

by drowning or dislodging larvae or facilitating death by 

disease. 


Crops should be monitored using a sweep net at the first 

sign of damage and throughout the growing season 

from late winter to late spring. 

Take a minimum of five sets of 10 sweeps and calculate 

the average number of larvae per 10 sweeps. 

If spraying, it is important to monitor 5-7 days after spray 

application to assess the effectiveness of treatment. 


Threshold guidelines indicate spraying is recommended 

when: 

• 50 larvae are collected per 10 sweeps for pre-flowering 

unstressed crops. 

• 30 larvae are collected per 10 sweeps for pre-flowering 

stressed crops. 

• 100-200 larvae are collected per 10 sweeps for 

unstressed crops with the majority of plants in flower. 



Larvae can cause damage to all growth stages of the 

canola plant. They feed on the foliage before flowering 

and, as flowering progresses, an increasing proportion 

of the larvae move to the floral buds, flowers and pods. 

Maturing pods are surface grazed or scarred by the 

larvae. They are not as damaging as native budworm as 

they do not chew into the pods. Premature shattering of 

pods rarely occurs. 

Larger larvae feeding on the underside of leaves can 

create holes, often with the upper surface intact, 

producing a window effect. 

Canola can tolerate considerable foliar feeding damage 

before crop yield is affected. Severe feeding damage can 

cause complete defoliation resulting in yield reduction. 

14 


If monitoring detects a rapid increase in DBM larvae and 

numbers exceed spray thresholds, a two-spray policy 

is thought to be more effective than a single spray. 

The second spray should be applied approximately 

seven days after the first if more than 20% of the initial 

population remains. Good spray coverage is critical 

for effective DBM control as more than 20% of the 

larvae reside in the bottom third of the plant. You should 

consider the size of the majority of the larvae before 

making a management decision. Target treatment at 

larvae

Lepidoptera: Pyralidae 

Lucerne seed web moth (Etiella behrii) 


larva 

adult 

Adult 

10 mm 

20 

30 40 50 

Orange/tan band 

running crossways 

on the forewings 

Wings greyish-brown 

and held over body at 

rest, giving moth slender 

appearance 

Prominent 

snout-like 

beak 

White strip 

along front 

edge of each 

wing edge, 

running along 

full length 

Larva 

Darkened head 

capsule that lightens 

to a golden brown 

when mature. 

(image of 4 th instar) 


Darker hardened 

area (cervical shield) 

behind head 

region 

Four pairs of abdominal 

prolegs, anal prolegs 

(prolegs not visible 

in image) 

Lucerne seed web moth can be confused with other 

snout moths (Pyralidae), such as weed web moth. Larvae 

can be confused with podding pests such as budworms. 

Lucerne seed web moth larval damage is associated with 

characteristic webbing of pods and flowers - budworms 

do not web. 


Lucerne seed web moth is widespread throughout 

Australia but it is generally only a major and irregular 

pest in lucerne-growing areas of southern Australia. 

Nearly 

complete ring of 

hooks (crochet) 

arrangement at base 

of prolegs 

Body colour: 

Green to cream 

with a pinkish tinge 

and several stripes 

running along 

the body 

The pinkish tinge 

becomes more 

pronounced as 

it ages 

The highest risk period is when pods mature prior 

to harvest in summer. Seed damage is sporadic over 

seasons, varying from light to severe infestations when 

an outbreak occurs. 

Lucerne seed web moth can have 2-3 generations per 

year depending on the temperature, location and host 

plant availability. In southern Australia, adults are first 

seen in late September with a second peak (generation) 

in November/early December. A third generation often 

occurs in late December/early January. 


15 




Lucerne seed web moth has been found on a wide range 

of native and introduced legume plants that include 

lucerne, lentils, lupins, field peas, medics, clovers and 

soy beans. 


Larvae can feed in the growing points, buds, flowers and 

inside pods, where there are few signs of damage during 

the early stages of attack, and internal larvae feeding can 

go unnoticed. Each larva usually damages more than 

one pod and several pods are often webbed together - 

this is characteristic of lucerne seed web moth. 

Female moths lay their eggs under the calyx or on 

the pod surface and these eggs hatch within 4-7 days, 

depending on the temperature. Newly hatched larvae 

bore into immature pods within a very short period after 

hatching, to begin feeding on developing grain. This 

results in inferior quality lentils and yield losses due to 

a reduction in grain weight and grain breakage. Once 

inside the pods, larvae are protected from insecticide 

sprays and damage is usually only identified at harvest. 


Successful lucerne seed web moth control relies on 

thorough crop monitoring in order to correctly time 

insecticide applications. In southern Australia, adults 

are first seen in mid to late September which usually 

coincides with early pod development. 

The degree-day model (found on the SARDI website 

- Etiella management in lentils) can be used to help 

identify the onset of significant lucerne seed web moth 

flight activity within crops and when in-crop monitoring 

should commence. 

16 


Suggested monitoring procedures 

• Sweep netting is a common method used for 

estimating moth numbers. Susceptible crops should 

be sampled at least once a week during podding 

for evidence of lucerne seed web moth activity. A 

minimum of three groups of 20 sweeps should be 

randomly undertaken within each field. 

• Pheromone trapping requires a minimum of two to 

three traps to be placed within a crop approximately 

25 cm above the canopy. 

• Light trapping is used at night to detect lucerne 

seed web moth moths in spring but a range of other 

insects will be collected and checking specifically for 

the lucerne seed web moth can be difficult. 

Check for the presence of young larvae and eggs on 

maturing seed pods when moths are present. 

Examine damaged growing points or pods particularly 

where webbing is seen. It is too late to prevent damage 

when webbing by mature larvae is detected. 



Predatory bugs such as glossy 

shield bug (Cermatulus nasalis) 

can attack lucerne seed web 

moth. A number of parasitic 

wasps and flies have also been 

recorded from larvae and 

pupae. 

Delay harvest or grazing period 

to prevent these coinciding 

with moth flights. 

Control volunteer legumes and 

other host plants. 

Ute Guides, Southern (pp. 27-28)/Western (pp. 30-31) and the SARDI website (Etiella management in lentils). 

Lucerne seed web moth management is based on 

timing spray applications to target adult moths before 

egg laying commences. Sprays are ineffective against 

lucerne seed web moth eggs and when larvae bore into 

pods they are physically protected from sprays. 

Recommended action threshold for lucerne seed web 

moth is 1-2 larvae collected in 20 sweeps. 

Chemical control with synthetic pyrethroids 

should aim to kill the adults before egg laying 

commences. 

Insecticides with short withholding periods 

should be used later in the season. 

Insecticide sprays applied to control native 

budworm early in the podding period may 

provide some control for lucerne seed web 

moth if present. Lucerne seed web moth 

monitoring should recommence no later than 

one week after spraying. 

Insecticides with a fumigant action may kill 

some larvae but control may not always be 

achieved.

BEETLES (Order Coleoptera) 

Coleoptera - sheath (koleos); wing (ptera) 

Beetles are the largest order of insects, including about 

one quarter of all the known insects in the world. There 

are around 28,200 described beetle species in Australia, 

divided into 113 families. 


Larva 

There are four major morphological types of larvae; 

eruciform, scarabaeiform, campodeiform and apodous 

(see p. 18). All have chewing (mandibulate) mouthparts 

and a hardened (sclerotised) head capsule. Many larval 

stages are considered to be the pest phase of beetles. 

Three pairs of legs (with the exception of weevil larvae) 

are present. The absence of prolegs with crotchets 

(specialised hooks) distinguishes beetle larvae from 

moth larvae. 

Adult 

Forewings are hardened into sheath-like wing covers 

(elytra) and they have a hardened body. All have chewing 

(mandibulate) mouthparts. 

Lifecycle 

Complete metamorphosis. 


cropping 

Cockchafers and dung beetles (F: Scarabaeidae): Mixed 

group with some larval pests and adult beneficials. Some 

adults are also pests. All larval stages are curl grubs, ‘C’- 

shaped larvae. Cockchafers are covered in detail in this 

section on page 19. 

True wireworms or click beetles (F: Elateridae): These 

soil dwelling larval pests are covered in detail in this 


False wireworms (F: Tenebrionidae): These soil-dwelling 

larval pests are covered in detail in this section on 

page 24. 

Weevils (F: Curculionidae): Adults have a snout 

(rostrum). All weevil larval stages are legless (apodous) 

and maggot-like in shape. Both adults and larvae can be 

damaging to plants. Weevils are covered together in this 


Bruchid/seed beetles (F: Chrysomelidae): Pest in the 

larval stage. The pea weevil (Bruchus pisorum) belongs in 

this family but it is not a true weevil, not having a weevil 

snout. This introduced pest beetle is one of a number of 

common worldwide pests in field pea and bean growing 

areas. This pest has an interesting lifecycle with the larvae 

beginning life in the growing pod and completing it in 

the dry seed. For further information on pea weevil refer 

to Ute Guides, Southern (p.55)/Western (p.44). 

Ladybirds (F: Coccinellidae): These predatory beetles 

are covered in detail in this section on page 29. 

Ground beetles (F: Carabidae): These predatory beetles 

are covered in detail in this section on page 31. 


17 


Eruciform Scarabaeiform Campodeiform Apodous 


Cylindrical elongated 

body. 

Short legs. 

Head & mouthparts 

oriented downwards. 

Less active and mobile. 

‘C’ - shaped body. 

Relatively short 

functional legs. 

Swollen lower abdomen. 

Tapering body. 

Well-developed legs. 

Large mouthparts 

directed forward. 

Highly mobile and active. 

Legless. 

Reduced mouthparts 

and antennae. 

Adapted to living in 

confined spaces. 


Groups 

False wireworms 



(Elateridae) 

Many non-target species 

18 

Groups 

Cockchafers and dung 

beetles (Scarabaeidae) 


Groups 

Ladybirds 


Carabids (Carabidae) 

Rove beetles 


Groups 

Weevils (Curculionidae)

COCKCHAFERS Coleoptera: Scarabaeidae 

Blackheaded pasture cockchafer (Acrossidius tasmaniae), Yellowheaded cockchafer 

(Sericesthis sp.) and Redheaded pasture cockchafer (Adoryphous coulonii) 


Blackheaded pasture cockchafer NOT IN WA 

Black head 

capsule 

*Flares and 

spurs on legs 

Dark brown 

to black 

Sriations 

(grooves) on 

elytra (wing 

covers) 

*Short 

functional 

legs 

*Abdomen 

swollen 

distally 

*Mouthparts 

oriented 

downwards 

*Spiracle 

behind head 

capsule 

*Clubbed antennae 

Broad 

shovel-like 

head 

Raster of larva 

‘U’-shaped lower 

groove 

larva 

adult 

10 mm 

20 

30 

Yellowheaded cockchafer NOT IN WA 


Redheaded pasture cockchafer NOT IN WA 


*Flares and 

spurs on legs 

Broad, light 

brown in 

colour 

Stout, dark 

brown/red in 

colour 

*Flares and 

spurs on legs 

* indicates character for all species 


‘Y’-shaped groove 


open groove 

larva 

adult 

larva 

adult 

Yellow head 

capsule 

10 mm 

Red head 

capsule 

10 mm 


20 

20 

30 

30 

19 



The larval stages of all cockchafers and dung beetles 

are ‘C’-shaped grubs that curl up when disturbed or 

handled. They have relatively short functional legs, the 

abdomen is swollen distally and their mouthparts are 

oriented downwards. 

Cockchafer species usually live in vertical tunnels in 

soil and are free-living. The presence of tunnels can 

sometimes make the soil appear spongy. 

WA Cockchafers 

Species of cockchafers found in Western Australia and 

eastern Australia differ. Although many WA species 

appear similar to those found in eastern Australia, most 

are not damaging. A few species (e.g. Heteronyx obesus) 

can cause extensive below-ground damage in some 

seasons. Larvae are soil-dwelling root feeders that do 

not come to the surface. Refer to Western Ute Guide 

(p. 46) for more detail. 

Blackheaded (BH) pasture cockchafers are foliage 

feeders and the presence of green material in tunnels is 

also a good indicator of this species. 

Yellowheaded (YH) cockchafer and Redheaded 

(RH) pasture cockchafer larvae are soil-dwelling (root 

feeders). Newly-hatched larvae are about 5 mm long. 

The Scarabaeidae family also includes other pest 

cockchafer species and beneficial species such as: 

• African black beetle (Heteronychus arator). 

Refer to Ute Guides, Southern (p. 64)/Western 


• Beneficial dung beetles. 

In general, beneficial dung beetles are found with 

brood balls. Brood balls are balls of dung on which 

dung beetles lay eggs. Eggs hatch into larvae which 

feed on the dung of the brood ball. 

Refer to Ute Guides, Southern (p. 150)/Western 



Similar to all other Scarabaeidae ‘C’-shaped larvae (e.g. 

dung beetles). Distinguishing between most species 

at the larval stage is difficult and generally only possible 

using a microscope to compare hair (setae) structure. 


WA Cockchafers are found throughout the state. Their 

presence in the soil does not always mean that damage 

will occur. The larval stages feed underground and 

are most damaging to seedling crops during autumn/ 

winter. Damage may occur every second year as some 

species have a two year lifecycle. 

20 


BH pasture cockchafers are found in higher rainfall 

areas in southeastern Australia (not WA). Larval growth 

rates depend on the number of rainy days during autumn 

and winter, which is when pastures and crops are most 

at risk. Pupation occurs towards the end of October 

with adults emerging during January to March. Their 

emergence and activity is dependent on the frequency 

of rainfall events. Adults live for several weeks and will 

lay egg batches on bare earth. One generation per year. 

YH cockchafers are found across southeastern Australia 

(not WA), including New South Wales, Victoria and South 

Australia. Larvae live in the soil until mid-late summer 

when they emerge as adult beetles. Cereal and pasture 

plants are most likely to be damaged from emergence 

to late autumn or early winter. One generation per year. 

RH pasture cockchafers are found throughout southeastern 

Australia (not WA), but are most common in 

south-west and central Victoria, the southern tablelands 

of New South Wales, south-eastern South Australia and 

northern Tasmania. Although they are typically found in 

higher rainfall zones, RH pasture cockchafers tend to be 

more numerous and problematic in drier years. Pastures 

are most likely to be damaged from emergence to late 

autumn or early winter. Although RH pasture cockchafers 

have a two year life cycle, they can be problematic every 

year if generations overlap. Larvae are present from 

autumn to spring and pupation occurs over summer. 

Adults remain in the soil until the following spring when 

they emerge, fly off, and then lay their eggs in the soil. 


Cockchafers are important pests of pastures and cereals. 

Crops sown into long term pasture paddocks are most at 

risk of attack. Adults do not feed on crops. 

BH pasture cockchafer larvae feed on the foliage of 

annual pasture species (e.g. subterranean clover), and 

occasionally perennial pasture species and cereal crops. 

YH cockchafer larvae mainly attack the roots of cereal 

crops but can also attack pastures. 

RH pasture cockchafer larvae attack the roots of 

clovers and a range of annual and perennial grasses, 

typically in the top 10 cm of soil. They also occasionally 

attack wheat. 

WA cockchafer larvae attack a range of crops and 

pastures. They can cause extensive damage to wheat 

crops.


BH pasture cockchafer larvae usually only come to the 

surface to feed after rain and they take enough food 

into their tunnels for 7-10 days. Most damage occurs to 

pastures during late winter and at the seedling stage in 

cereals when larvae eat all the leaves. The amount of 

damage varies from year to year. 

YH cockchafers are primarily cereal root feeders and 

they will damage roots of young plants while foraging 

for soil organic matter. Damaged plants initially grow 

normally but wither and die at tillering, resulting in bare 

patches in the crop. Damage is worse under drought 

conditions as the plant’s capacity to replace severed 

roots is reduced. 


Inspect susceptible paddocks prior to sowing. Check 

established pastures or weed growth in autumn to early 

winter, particularly in areas where bare batches were 

present over summer. Use a spade to remove soil from 

the ground and count the number of grubs. Grubs are 

usually found in the top 80 mm of moist soil. Repeat 

multiple times across the paddock. 

RH pasture cockchafers are primarily root feeders. 

Moisture stimulates the larvae to move closer to the 

soil surface in autumn where they feed on roots of 

newly emerging seedlings. High numbers of grubs 

sever the roots of pasture plants below the soil surface, 

which allows the pasture to be rolled back like a carpet. 

Damage can also result in completely bare regions 

within a paddock, ranging in size from small isolated 

patches to very large areas. 



For all cockchafers 

• Birds prey upon grubs and are 

most effective after cultivation or 

tillage. 

• Several predatory and parasitic 

flies and wasps. 

• Other general predatory 

invertebrates. 

• Fungal pathogen Metarhizium 

spp. 

Ute Guides, Southern (pp. 61-63)/ Western (p. 46). 

For WA cockchafers 

• If damage is anticipated, increase 

sowing rate for higher plant 

density. 

For BH 

• Avoid overgrazing of pastures as 

bare batches are more attractive 

to adults laying eggs during 

summer and early autumn. 

For YH and RH 

• Cultivation 

• Grazing of pasture during late 

spring, summer and autumn (for 

YH) and heavy grazing in spring 

(for RH). 

• Re-sow affected areas using a 

higher seeding rate. 

• Re-sowing is best done using a 

method which disturbs the soil 

surface, leaving grubs vulnerable 

to predation. 

• Sowing less palatable crops (e.g. 

oats). 

For WA cockchafers 

• Surface applications of 

insecticides are not effective. 

Chemical seed treatments or 

insecticides incorporated during 

seeding can assist in control. 

For BH 

• Foliar application of an insecticide 

is effective, particularly on young 

larvae before they begin to feed 

on green plant material. 

For YH and RH 

• Surface-applied insecticides are 

generally not effective given the 

subterranean feeding habits of 

larvae. 


21 


TRUE WIREWORMS or CLICK BEETLES Coleoptera: Elateridae 

Various species 


larva 

10 mm 

20 

30 40 50 

Larva 

Flattened head 

and mouthparts 

oriented 

downwards 

Hardened skin 

(cuticle sclerotised) 

Elongated 

cylindrical body 

shape (eruciform) 

– slightly flattened. 

Slightly tapering at 

both ends – oval in 

cross section 

Short legs 


There are numerous true wireworm species in Australia 

but they are not described in detail here and are only 

discussed at the family level. 

22 

Adult 

Flattened 

body 

Creamy yellow 

body colour 

with darker head 

region 

Point at the 

base of the thorax 

(pronotum) 


Two upturned 

spines 

Serrated 

dorsal plate 

Anal 

proleg 

Adults make a click sound when they flick themselves 

over after being placed on their backs. 

The lifecycle of many true wireworm species is not fully 

understood. The lifecycles of most pest species probably 

take more than a year to complete.


Larvae are similar to those of false wireworms 

(Tenebrionidae) but are flatter in appearance and can 

grow larger. The predatory larvae of carabid beetles 

(Carabidae) are also easily misidentified as wireworms 

and may be found in similar environments. 


True wireworms are more common on wetter soils and 

are found under plant debris and in the soil. They can 

be found together with false wireworms and, when this 

occurs, true wireworms are usually more numerous than 

false wireworms in some regions. 

Larvae are soil-dwelling pests that can be very damaging 

to cereals during crop emergence. This is rarely the case 

in WA and sporadic in other southern states. 


Germinating cereals are most at risk. Crops following 

long term pasture (fallow for 4-5 years) as well as crops 

sown on recently cultivated land are more susceptible. 

Stubble retention and trash can also favour these pests. 


Larvae feed on seed and bore into the underground 

stems of cereal plants. They may also damage the roots 

of seedlings. Germinating seedlings can be ring-barked 

and hypocotyls severed just below the soil surface. 

Plants wither and die after emergence and damage can 

result in a thinned crop or bare patches, which become 

visible shortly after crop emergence. 


Check under stubble prior to sowing, especially if 

coming out of long term pasture. 

Early identification and detection of these pests prior 

to seeding and applying a treatment at seeding will 

prevent additional costs of re-sowing damaged areas. 

As a threshold guide, around 10 larvae/m 2 may 

warrant control. Average densities of approximately 

40 larvae/m 2 can cause enough damage to necessitate 

re-sowing. 



Carabid beetle larvae feed on 

soil-dwelling insects, including 

wireworms, but are usually not in 

high enough numbers to effectively 

control large pest populations. 

There are no other known parasites, 

predators or pathogens that 

effectively control wireworms in 

cereal crops. 

Southern Ute Guide (p. 60). 

Removing excess stubble and 

trash is an effective strategy where 

this resident pest is a problem in 

continuous years. 

Re-sow affected areas using a higher 

seeding rate. 

Using a re-sowing method that 

disturbs the soil surface, leaving 

larvae vulnerable to predation, is 

recommended. 

Insecticidal seed dressings may offer 

some protection from moderate 

larval numbers. 


23 


FALSE WIREWORMS or MEALWORMS Coleoptera: Tenebrionidae 



Larva 

Adult 

*Head and 

mouthparts oriented 

downwards 

*Short legs 

(stronger pair of 

front legs) 

*Simple (threadlike) 

antennae 

Dome-shaped body 

usually brown in 

colour and 

covered in soil 

Striations 

(pits) on elytra 

(wing covers) 

*Elongated 

cylindrical body shape 

(eruciform) with ring like 

segmentation – round 

in cross section 

*Hardened 

skin (cuticle 

sclerotised) 

Two upturned 

spines 

Vegetable beetle 

Gonocephalum spp. 

Grey false wireworm 

Isopteran sp. 


Bronzed field beetle 

Adelium brevicorne 

larva 

adult 

24 

10 mm 

20 

Shiny creamytan 

in colour 

larva 

adult 

Dark grey to 

black in colour 

10 mm 

Shiny uniformly 

dark brown in 

colour 

Shiny black to 

bronze in colour 

30 40 50 


20 

30 40 50 

larva 

adult 

Flattened and 

dull brown 

in colour 

Eastern false wireworm 

Pterohelaeus sp. 

Cream-tan to 

yellow-orange in 

colour with darker 

rings 

larva 

adult 


10 mm 

10 mm 

20 

20 

Shiny browngreyish 

in colour 

with paler 

under parts 

30 40 50 

Dull black in 

colour with 

flanged edges 

30 40 50


Larvae are similar to those of the true wireworm 

(Elateridae) but are rounder in cross-section and not 

flattened or tapered. The predatory larvae of carabid 

beetles (Carabidae) are also easily misidentified as false 

wireworms and may be found in similar environments. 


False wireworms are common in fine textured soils, with 

high levels of organic matter. They are not usually a 

problem on compacted soil (e.g. tyre tracks). 

Stubble retention and trash can favour these pests and 

some species can attack successive crops. Both the 

larvae and adults may cause damage depending on the 

crop and time of year. 


Vegetable beetles are minor pests that attack summer 

(e.g. sunflowers) and winter crops (e.g. emerging canola 

and cereals). 

Bronzed field beetle larvae and grey false wireworms 

can attack canola at emergence in some seasons. 


Vegetable beetle larvae bore into germinating 

cereal seeds (especially when swelling) and chew on 

seedlings below ground level. Adults sometimes attack 

germinating canola at ground level, which results in 

ring-barking or completely cut stems. 

Bronzed field beetle larvae attack germinating canola 

above the ground and at the base of seedlings. Ringbarking 

and death of plants may occur. 

Grey false wireworm larvae attack germinating canola 

just below the ground, which results in damage to the 

crown and roots. 


Check under stubble prior to sowing, particularly if 

the paddock is coming out of long term pasture. Early 

identification and detection of these pests (possibly 

using germinating seed traps prior to seeding) is 

important. Seed treatments can be applied to prevent 

damaged areas when pest numbers are high. 

It is important to be aware of the crop growth stage as 

cotyledons are most susceptible, whilst advanced plants 

will be able to out-grow moderate pest pressure. 



Carabid beetle larvae feed on 

soil-dwelling insects, including 

wireworms, but are usually not in 

high enough numbers to effectively 

control large pest populations. 

There are no other known parasites, 

predators or pathogens that 

effectively control wireworms 

in crops. 

Ute Guides, Southern (pp. 56-59)/ Western (pp. 43, 45). 

Removing excess stubble and trash is 

an effective strategy where this pest 

is a problem in successive years. 

Early sowing and crop establishment 

prior to egg hatching may result 

in plants being able to outgrow 

damage. 

Re-sow affected areas using a higher 

seeding rate. 

Using a re-sowing method that 

disturbs the soil surface, leaving 

larvae vulnerable to predation, is 

recommended. 

Compacting soils post sowing to 

improve seedling vigor has been 

shown to have some benefit against 

grey false wireworm. 

Insecticidal seed dressings may offer 

some protection from moderate 

larval numbers. 

A foliar application can be used 

for partial control of bronzed field 

beetle larvae as they attack crops 

above ground. 


25 


WEEVILS Coleoptera: Curculionidae 

The largest family of beetles. There are over 6,000 described species in Australia. 


Adult 

Elongation 

of front 

head and 

rostrum 

Antennae usually 

bent (elbowed) 

and clubbed. 

Situated on rostrum 

Rostrum 

(snout) 

Rigid 

body 

Thorax 

Elytra (hardened forewings). 

Membranous hindwings (concealed 

beneath forewing) may be 

present or absent 

Rostrum - shapes vary 

between genus/species 

Larva 


26 

Small hardened 

head capsule with 

small chewing mouth 

parts (mandibles) and 

antennae 

Legless (maggotlike) 

- no ‘true’ 

legs or 

prolegs 

As there are so many species, weevil identification is 

only discussed here at the family level. 

Broadacre weevil pests are not covered in detail in this 

manual. Only adult size differentiation and key field 

identification characters are shown. 


Body colour usually creamy 

but can also be green/yellow 

Presence of hair (setae) 

can be highly variable 

from stout and distinct 

to short or absent 


It is difficult to distinguish between the larval stages 

of weevil species. Larval stages are legless (apodous), 

maggot-like in shape and may be confused with fly 

larvae which are also legless. Unlike weevils, most fly 

larvae do not have a well-defined head capsule.

White 

fringed 

weevil 

Small 

lucerne 

weevil 

Vegetable 

weevil 

Fullers rose 

weevil 

Greybanded 

leaf 

weevil 

Spine-tailed 

weevil 

Spotted 

vegetable 

or 

Desiantha 

weevil 

Polyphrades 

weevil 

Mandalotus 

weevil 

Sitona 

weevil 

Cabbage 

seedpod 

weevil 

NOT PRESENT IN 

AUSTRALIA 

Increasing in size 

BIOSECURITY 

THREAT 


2-3.5 mm 3-5mm 3-5mm 4mm 7mm 7mm 8mm 8mm 8mm 10mm 10-13mm 

White stripe 

down sides of 

body 

Grey with 

short broad 

snout 

V-shaped mark 

on back of 

abdomen 

White stripe 

on side of first 

two segments 

Paler banding 

on rear 

abdomen 

Females: two 

spines on end 

of abdomen 

Spotted 

abdomen 

Limited 

distribution 

(Eyre Pen.) 

Covered in dirt 

Paddle-shaped 

setae (hairs) 

on elytra 

(wing covers) 

3 stripes on 

thorax 

Distinctive 

long narrow 

downward 

curved 

rostrum 

Ute Guide 

WA p. 41 

SA p. 51 

Ute Guide 

WA p. 39 

Ute Guide 

WA p. 37 

SA p. 47 

Ute Guide 

WA p. 42 

SA p. 54 

Ute Guide 

SA p. 49 

Not in WA 

Ute Guide 

WA p. 38 

SA p. 48 

Ute Guide 

SA p. 53 

Not in WA 

Ute Guide 

SA p. 52 

Not in WA 

Ute Guide 

WA p. 40 

SA p. 50 

Ute Guide 

WA p. 143 

SA p. 176 


27 


The distinctive appearance of adult weevils make them 

unlikely to be confused with other beetles. However, 

distinguishing between the many species of weevils can 

be difficult. Mandalotus weevil (Mandalotus spp.) adults 

in particular are highly variable in appearance. 


Weevils can be found in a wide range of habitats and 

many are known as pests of agriculture, stored products, 

horticulture and forestry. They feed on vegetable parts 

including shoots, buds, leaves, roots, wood and bark. 

Some also feed on stored grain and vegetable products. 

As larvae are legless, they are restricted in their 

movement and distribution. They may be restricted 

above ground (e.g. vegetable weevil) or confined 

underground (e.g. Desiantha weevil). Adults are more 

mobile and can be winged and active flyers, or wingless 

and walk or march en masse. Adults and larvae can both 

cause damage depending on the crop and time of year. 


A variety of sampling techniques can be used depending 

upon the habitat. For example, pitfall traps can be used 

to sample ground-dwelling weevils. For above-ground 

species, visual direct searches are appropriate. Often, 

direct searches may need to be undertaken at night 

when many species are active. 


Scalloping on 

leaf edges 

Ring barking 

plants at ground level 

results in lopping 


Bullet hole 

on leaves 

28 

Thinning of plants 

and bare patches due to 

underground feeding on 

roots/seeds 


LADYBIRD BEETLES Coleoptera: Coccinellidae 

Various species - approximately 500 Australian species. 

Generalist and transient 

BENEFICIAL 


larva 

10 mm 

20 

30 40 50 

adult 

Larva Pupa Adult 

Elongated and 

tapered at rear 

Grey-black with 

orange-yellow 

markings across body. 

May have spines 

or white fluffy material 

Black ladybird 

Rhyzobius sp. 


blackish legs 

White-collared ladybird 

Hippodamia variegata 


mandibulate 

mouthparts 

Colour and pattern variations of different species 

Striped ladybird 

Microspis sp. 

Common spotted ladybird 

Harmonia conformia 

Transparent hindwing 

concealed underneath 

elytra (forewing). 

Patterns of black over 

red, orange or yellow 

Minute two-spotted ladybird 

Diomus notescens 

Transverse ladybird 

Coccinella transversalis 


Round to 

oval shaped 

29 


There are numerous species, but three species commonly 

found are the white collared ladybird, the common 

spotted ladybird and the transverse ladybird. Adults are 

round to oval shaped, with black spots on red, orange or 

yellow shells. Larvae have grey/black elongated bodies 

with orange markings and may be covered in spines or 

white fluffy wax material. Ladybird eggs are generally 

yellow, spindle ‘football’ -shaped and laid standing on 

end in clusters on plants. 

Lifecycle 


Ladybird beetles can be found throughout the year. The 

highest numbers are observed in spring to early summer 

when they can undergo several generations. Each 

generation takes approximately one month (depending 

on the species) under ideal conditions. Female ladybird 

beetles can lay up to 200-1000 eggs in a lifetime, which 

may span several months. 


The larger more colourful (contrasting patterns/spots) 

ladybird adults are readily identifiable but smaller drab 

species can be confused with other oval-shaped beetles 

such as leaf beetles (Chrysomelidae). 

Distribution/habitat 

Ladybirds are common throughout Australia and can 

be found in almost all habitats, particularly in canola 

and wheat crops during spring, where there has been a 

large build-up of aphids. They may also be seen on some 

native vegetation and in domestic gardens. 

They are most prevalent in spring and seen occasionally 

in autumn when large populations move to areas rich 

in prey. 

Pests attacked/impact on pests 

Most ladybird adults and larvae are predatory and prey 

on a range of pests including aphids, leafhoppers, thrips, 

mites, moth eggs and small larvae. They are particularly 

voracious feeders on aphids and in some seasons the 

increase in ladybird populations (often in combination 

with lacewings and other beneficial insects) will be 

sufficient to keep aphid numbers below economically 

damaging levels. 

Many adults supplement their diet with pollen and a 

sugar source (e.g. nectar). 



Predatory ladybirds can be confused with the 28-spot 

ladybird (Henosepilachna vigintioctopunctata), which 

is a large (8 mm) leaf-eating pest species found in 

horticultural areas, but rarely seen in broadacre. 

30 


CARABID BEETLES or GROUND BEETLES 

Coleoptera: Carabidae 

Various species - approximately 2,500 Australian species. 

Generalist and residential 

BENEFICIAL 


larva 

adult 

10 mm 20 30 40 50 

a few species can be larger 

Larva 

Large welldeveloped 

mouthparts 

directed forward 

Well 

developed 

legs 

Semi-flattened, 

cream to brown 

body with a darker 

head region 

Two long 

hair-like processes 

projecting from last 

body segment 

Adult 

Rows/striations 

running along elytra 

(wing covers) 

Transparent 

hindwing concealed 

underneath elytra 


and long legs 

Colour and pattern variations of different species 

‘Hot water 

bottle’ body 

shape – distinct 

constriction 

Bulging eyes 

Large welldeveloped 

mouthparts 

protruding forward 


31 


Most species are soil-dwelling and move rapidly. 

Lifecycle 


There are many different species and their lifecycles 

can differ greatly. Most species have a one or two year 

lifecycle. Some breed in late summer and autumn 

and then hibernate as larvae through winter. Others 

hibernate as adults and reproduce in spring or early 

summer, after which the beetles usually die off, and a 

new generation appears in autumn. 


All carabids can be distinguished by their large mouthparts 

that are directed forward. 

Larvae may be mistaken for larvae of true wireworms 

(Elateridae) or false wireworms (Tenebrionidae) as they 

are similar in shape and soil-dwelling. However, carabid 

larvae have very prominent mouthparts in keeping 

with their predatory lifestyle. They also have processes 

projecting from their last abdominal segment, which 

are hair-like in structure and usually longer than those in 

true and false wireworms. 


Carabid beetles are widespread across Australia. Many 

species are nocturnal and can only be found during the 

day under tree bark, logs or among rocks. Some species 

have been found to increase in numbers in paddocks 

practicing minimum/no-till and stubble retention. 

Refuges (beetle banks) are considered beneficial in 

fostering carabids to help control pests in broadacre 

crops. 


Adults and larvae both feed mostly on ground-dwelling 

invertebrates. This includes a wide range of soft-bodied 

pests including wireworms, cockchafers, caterpillars, 

earwigs and slugs. Most carabid species are useful in 

suppressing pest populations, while a small number also 

feed on plant vegetation. 

Ute Guides, Southern (p. 139)/ Western (p. 115). 


Carabid beetles are also often confused with true and 

false wireworm beetles. Many adults have a characteristic 

flattened ‘hot water bottle’–shaped body, with pitted 

groove lines running along the wing covers. They also 

possess large bulging eyes. Some carabid beetles such 

as Calosoma spp. are conspicuous due to their bright 

metallic green colour. Carabid beetles usually move 

faster than wireworms and can be shinier. 

32 


BUGS (Order Hemiptera) 

Hemiptera - half (hemi); wing (ptera) 

The order Hemiptera is divided into three groups 

(suborders) each with distinct features: 

• Auchenorrhyncha (leaf hoppers) - pairs of wings 

similar in structure (not shape); 

• Heteroptera (e.g. nabids, assassin bugs and shield 

bugs) - forewings have half of the wing thickened 

(hardened) to form a hard leathery cover and a softer 

membranous rear wing; 

• Sternorrhyncha (e.g. aphids, scale insects, lerps and 

mealy bugs) - pairs of wings similar in structure (not 

shape). Some can be wingless. 

There are 6,000 hemipteran species described in Australia, 

in 100 different families. 


Nymphs 

Most resemble adults but are smaller, wingless and less 

developed. 

Adult forms 

While the appearance of bugs varies widely, most bugs 

have two pairs of wings. Some adult forms are wingless 

(e.g. aphids). Bugs have piercing and sucking mouthparts 

which are often modified to form a hardened stylet/ 

rostrum/proboscis or beak. The proboscis of bugs 

contains cutting blades and a two-channelled tube. 

Bugs feed by cutting into a plant or animal and sending 

saliva down one of the tubes to begin digestion. The 

liquid food is then sucked up the other tube. When 

insects are resting, the proboscis is often tucked up 

under the body between the legs. 

Lifecycle 

Incomplete metamorphosis. 


cropping 

Aphids (F: Aphididae): There are many pest aphid 

species, including a key biosecurity threat. Aphids are 

covered in detail in this section on page 34. 

Leafhoppers (F: Cicadellidae): Leafhoppers are 

generally small, green insects that puncture leaves and 

may leave a pattern of bleached marks. They are minor 

and sporadic pests in broadacre crops. Leafhoppers are 

not covered in this manual. For further information refer 

to Ute Guides, Southern (p. 80)/Western (p. 61). 

Mirids (SF: Miridae): Mirids are similar to leaf hoppers. 

Some mirids are predatory. Mirids are not covered in 

this manual. For further information refer to Ute Guides, 

Southern (p. 69)/Western (p. 51). 

Seed Bugs (SF: Lygaeoidea): Rutherglen bug (Nysius 

vinitor) belongs to this family and it is a common but 

sporadic native pest in broadacre crops. It can breed 

abundantly, if rain allows flowering and seed set of 

plants in warm weather. Nymphs are different in colour 

and shape to adults. Seed bugs are not covered in this 

manual. For further information on Rutherglen bugs 

refer to Ute Guides, Southern (p. 65)/Western (p. 49). 

Shield and stink bugs (F: Pentatomidae): This family 

contains both beneficial insects (e.g. the glossy shield 

bug, Cermatulus nasalis) and some sporadic pests, which 

are more common in warmer climates (e.g. the green 

vegetable bug, Nezara viridula). Shield and stink bugs 

are not covered in this manual. For further information 

refer to Ute Guides, Southern (pp. 66-68)/Western 

(p. 50, 117, 118). 

Nabids (F: Nabidae): These bugs are predators, attacking 

a wide range of prey. Nabids are also called damsel bugs 

and tend to be more delicate in structure than assassin 

bugs. Nabids can also eat plants and are regarded as 

omnivores. They are covered in this section on page 47. 

Assassin bugs (F: Reduviidae): These bugs are predators, 

attacking a wide range of prey. Assassin bugs are not 

covered in this manual. For further information refer to 

Ute Guides, Southern (p. 142)/Western (p. 120). 


33 


CROP APHIDS 

Hemiptera: Aphididae 

Key aphid characteristics 

• Piercing sucking mouthpart - needle-like mouthpart (stylet/proboscis) on the underside of the body. 

• Siphuncles (cornicles) - paired tube-like projections (on 5 th abdominal segment); wax secreting structures; 

characteristic shape and size. 

• Cauda - tail-like process terminating the abdomen; characteristic size, shape and hair pattern. 

• Segmented antennae – 4 to 6 segments; last antennal segment can be characteristic 

(e.g. length of terminal segment relative to the base segment). 

• Tubercle - small humps on the forehead between antennae. 

• Wings - adults can have wings or be wingless. 

Compound 

eye 

Antennal or 

frontal tubercle 

Variations in last antennal segment 


34 

Compound 

eye 

Abdomen 

Abdominal 

spiracle 

Head 

Cauda 

antenna 

iii 

ii 

i 

Source: Modified from Krono & Papp (1977) 


iv 

Cauda 

Cornicle 

(Siphunculus) 

v 

vi 

Rostrum 

ii 

Tarsus 

Femur 

i 

Tibia 

Tibia 

i 

vi 

Source: Modified from Krono & Papp (1977) 

Side view of abdomen 

Siphunculus 

Segment 8 

Genital 

aperture 

Source: Modified from Blackman and Eastop (2000) 

ii 

Tarsus 

Base TP 

process 

Base Terminal 

Base Terminal process 

Cauda

General aphid lifecycle and biology 

In Australia, most pest aphid species only produce 

females, which may be winged (alates) or wingless 

(apterae), and these give birth to live young. In other 

countries some aphid species have different (or altered) 

lifecycle phases (e.g. sexual/asexual) that are initiated 

by host-insect interactions and/or environmental 

conditions. Many aphids are plant host (crop) specific. 

Some aphids are vectors of crop diseases that can be 

detrimental to growth and limit yield. These diseases 

include barley yellow dwarf virus in cereals, cucumber 

mosaic virus in lupin and pea seed borne mosaic virus 

in field peas. These viruses have the largest yield impact 

when they are introduced early in the life of the crop, 

usually within the first ten weeks of growth. Aphids are 

efficient in spreading diseases due to their sap-sucking 

mouthparts. Transmission occurs via feeding on the 

vascular tissue (phloem) of infected plants. Once the 

virus is picked up, it can be carried in the salivary glands 

or restricted to the stylet of the aphid. The virus can be 

carried for a long (persistent transmission) or short (nonpersistent) 

period of time after aphids feed on infected 

plants. These different modes of transmission influence 

the effectiveness of chemical sprays against virus spread. 

Figure 4.1 An example of an aphid lifecycle (Aphis sp.) 

Source: Modified from 

Blackman and Eastop 

(2000) 

Primary host plant 

eggs 

Spring migrants 

alate 

males 

apterous 

autumn migrants 

Summer/autumn 

Aphids require specific host plants for their 

survival. Aphid populations usually decline over 

summer. The availability of suitable host plants (e.g. 

specific weed families on roadsides and verges) allows 

populations to survive and increase. Winged aphids 

move into crops in autumn and aphid numbers 

will usually start to build up along crop edges. The 

formation of winged aphids and aphid movement 

generally increases when host plants are dying or when 

overcrowding occurs with high populations. 

Winter 

Low temperatures and heavy rainfall in winter often limit 

aphid populations. Nymphs go through several growth 

stages, moulting at each stage into a larger individual. 

Sometimes the delicate pale aphid skins or casts (the 

exoskeleton they have shed) can be seen. Nymphs do 

not have wings. 

Spring 

Spring often triggers a rapid increase in aphid numbers 

as increasing temperatures and flowering crops provide 

favourable breeding conditions. Most aphids form 

dense colonies before winged aphids are produced. 

These move onto surrounding plants further into the 

crop creating hot spots. In some seasons, aphids form 

large colonies (especially at flowering) and heavy 

infestations may produce large amounts of a sticky 

secretion (honeydew). 

Secondary host plant 

alate 


35 


APHID VIRUSES 

Aphids as virus vectors in pulse crops 

There are many aphid species that transmit viruses in 

pulse crops (Table 4.1). The major species are green 

peach aphid, cowpea aphid, pea aphid and bluegreen 

aphid but this list is not exclusive. Aphids spread 

viruses between plants by feeding and probing when 

they fly during autumn and spring. 

The ability to transmit particular viruses differs with 

each aphid species and viruses may be transmitted in 

a persistent or non-persistent manner. This influences 

the likelihood of plant infection (Figure 4.2). 

For non-persistent transmission, the virus is usually 

restricted to the stylet of the insect. This means virus 

spread generally only occurs over short distances and 

aphids only remain infective for periods from a few 

minutes up to a few hours. For persistently transmitted 

viruses, the virus is ingested, passes through the gut 

and then moves to the salivary glands where it can 

potentially be transmitted to other plants. The aphid 

retains the virus for the remainder of its life. 

Table 4.1 Some aphids known to transmit viruses in pulse crops 

Aphid Species Common Name Cucumber Mosaic 

Virus (CMV) 

Pea Seed-borne Mosaic 

Virus (PSbMV) 

Beet Western 

Yellows Virus (BWYV) 


36 

Acyrthosiphon pisum Pea ahid 50% 

Aphis craccivora Cowpea aphid 9.4% 

Acyrthosiphon kondoi Blue green aphid 6.1% 

Myzus persicae Green peach aphid 10.8% 96% 

Lipaphis erysimi Turnip aphid 3.9% 

Macrosiphum euphorbiae Potato aphid 14% 

Aphis gossypii Melon or cotton aphid 

Aulacorthum solani Foxglove aphid 

Brachycaudus helichrysi Leafcurl plum aphid 

Brevicoryne brassicae Cabbage aphid 

Hypermyzus lactucae Sowthistle aphid 

Myzus ascalonicus Shallot aphid 

Myzus ornatus Ornate aphid 

Rhopalosiphum maidis Corn aphid (in glasshouse) 

Rhopalosiphum padi Oat aphid (in glasshouse) 

Therioaphis trifolii Spotted alfalfa aphid 

Uroleucon sonchi Brown sowthistle aphid 

Note that many more vectors are listed for PsbMV and/or CMV. 

% is the virus transmission rate for various species 

Figure 4.2 Persistent versus non-persistent transmission of viruses 

Persistent transmission 

1-2 hours feeding e.g. BWYV 

x 


Non-persistent transmission 

Instant transmission e.g. CMV, AMV 

Aphicides for non-persistent transmission are likely to be ineffective. 

Early management strategies are important. 

x 

References and further reading: 

Aftab and Freeman (2006) Temperate 

Pulse Viruses: Pea Seedborne Mosaic 

Virus (PSBMV) AG1267 DPI-Victoria 

Coutts and Jones (2006) Aust J Ag Res 

57,975-982 

Freeman and Aftab (2006) Temperate 

Pulse Viruses: Cucumber Mosaic Virus 

(CMV) AG1207 DPI- Victoria 

ICTVdB Virus Descriptions http:// 

www.ncbi.nlm.nih.gov/ICTVdb/ 

ICTVdB/00.039.0.02.003.htm 

Jones and Proudlove (1991) Ann App 

Biol 118, 319-329 

Jones et al. (2008) Plant Path 57, 842- 

853 

McKirdy et al. (2005) Viruses diseases of 

chickpea Farmnote 16/97 www.agricwa. 

gov.au 

Nault et al. (2009) Environ Entomol 38, 

1347-1359

CEREAL APHIDS 

Corn aphid (Rhopalosiphum maidis) and Oat aphid (Rhopalosiphum padi) 


Corn aphid 

adult 

10 mm 

20 

30 

Oblongshaped 

Antennal 

segment VI 

Terminal process 

Base ½ as long as 

terminal segment 

Basal portion 

Two dark 

patches at 

the base 

of each 

siphuncle 

Pointed and 

tapering tip on 

siphuncles, 

not clearly visible 

in this image 

Oat aphid 

adult 

10 mm 

20 

Pearshaped 

Rust-reddish 

patch at the 

base of abdomen, 

in between 

siphuncles 

Cereal aphids are similar in colour with only subtle 

differences. Corn aphids tend to be light green to dark 

olive in colour and oat aphids olive-green to black in 

colour. 

30 

Blunt tip on 

siphuncles 

Antennal 

segment VI 

Terminal process 

Basal portion 

Base ¼ as long as 

terminal process 

A definitive diagnostic character to distinguish between 

oat and corn aphids (both adults and nymphs) is the 

length of the terminal part of the antennae relative to 

the base of the antennae (see diagram above). 


37 




These aphids can be confused with each other and other 

minor cereal aphids (e.g. rose-grain aphid, grain aphid 

and rice root aphid). 


Cereal aphids can be found all year round and on all cereal 

crop growth stages. They sometimes cause feeding 

damage to cereals when there is a rapid increase in their 

reproduction and populations rise above economically 

damaging levels, usually in spring. 

The two major cereal aphids can vector plant diseases 

such as barley yellow dwarf virus (BYDV). This is more 

common in high rainfall cropping zones where virusinfected 

self-sown cereals and grasses are present, along 

with large numbers of aphids during the early growth 

stages of new season crops. 


Oat aphids mainly attack oats and wheat, but can occur 

on all cereals and grasses. 

Corn aphids mainly attack barley, but can also attack 

other cereals and grasses. 

Both aphid species may be found during summer/early 

autumn on a range of volunteer grasses (alternate host 

plants) and self-sown cereals. 


Direct feeding damage by large numbers of aphids on 

plants can result in sap removal that can cause nutrient 

loss and plant-wilting. Visual symptoms are usually not 

very obvious until close inspection of leaf whorls and 

sheaths, where dark-coloured masses of aphids may 

be seen. In some cases, aphid colonies infest the seed 

heads and congregate in large numbers. 



Hover fly, lacewing larvae 

and ladybirds are known 

predators that help 

suppress populations. 

Aphid parasitoid wasps, 

evident by the presence 

of ‘mummies’. 

Naturally occuring 

aphid fungal diseases 

can dramatically affect 

populations. 

38 

Summer/autumn 

pre-season 

weed control by 

heavy grazing or 

herbicides to control 

alternate host plants 

(e.g. volunteer 

grasses and cereals). 


Large amounts of honeydew (aphid exudates) and black 

sooty mould may be seen in prolonged, severe cases. 


Direct visual searches and/or sweep netting. 

Regular monitoring for cereal aphids should start in late 

winter and continue through to early spring with more 

frequent monitoring at the most vulnerable crop stage 

(stem elongation to late flowering). Check at least five 

points over the entire paddock including representative 

parts. Visually search for aphids on a minimum of 20 

plants at each point and count the number of tillers 

infested with aphids. 

For aphid-prone areas (high rainfall), regular monitoring 

is recommended from crop emergence in autumn, to 

detect aphids moving into crops, particularly along 

paddock edges. Very few aphids are required to transmit 

BYDV from infected to healthy seedlings. If aphids are 

seen, it may be too late for control unless plants are at 

the early seedling stage. 

When widespread early infection occurs, BYDV can 

reduce grain yields by up to 50%. More commonly, the 

disease is confined to patches close to crop edges, where 

early aphid disease transmission occurred. 

Western Australian recommendations for aphid feeding 

damage action thresholds on cereals at tillering is to 

consider control if aphid populations exceed 15 aphids/ 

tiller on 50% of tillers for crops expected to yield 3 t/ha 

or more. 

Western Australian research on aphid feeding damage 

in the absence of BYDV demonstrated variable yield 

losses up to 10% and reduction in seed size with aphid 

infestations at these levels. 

BYDV control: 

Use of appropriate insecticide seed dressings and/or synthetic 

pyrethroid sprays in the first eight weeks of crop development. 

Aphid feeding damage: 

Seed treatments delay colonisation. 

Border spraying (e.g. autumn/early winter) when aphids begin 

to colonise crop edges may provide sufficient control. 

Selective chemicals (i.e. pirimicarb) should be considered 

because they are effective against aphids but relatively 

harmless to beneficial species and other non-targets. 

Ute Guides, Southern (pp. 70-71)/ Western (pp. 52-53).

CEREAL APHIDS 

Russian wheat aphid (Diuraphis noxia) 




adult 

10 mm 

20 

30 

Short antennae 

Elongated spindleshaped 

body 

Pale green in colour 

Dual tail appearance 

(cauda - bifurcate) 

Siphuncles 

not visible 

Early feeding 

damage: streaking along 

plant veins (white and 

purple in colour) 


Russian wheat aphid (RWA) can be confused with 

other cereal aphids but the lack of visible siphuncles 

distinguishes this exotic aphid threat from common 

cereal species. 

Distribution and means of spread 

RWA has spread throughout all major grain growing 

countries except Australia. If this exotic pest enters 

Australia it has been estimated that it could cause 

significant damage to crops, resulting in up to 60-75% 

yield loss. 

Later feeding 

damage: flag leaf 

curling and immaturity 

of grain head; prostrate 

appearance 

As with all aphids, RWA would spread through crops by 

active flight or wind currents. Long-distance dispersal 

overseas also occurs through hitchhiking on machinery, 

clothes or plant material. 


Wheat, barley, triticale, oats and rye are preferred hosts, 

but RWA can attack most cereal crops. 

This species spends its entire lifecycle on cereals and 

grasses. Volunteer cereals and grasses around crop edges 

and road verges can provide a food source, particularly 

over summer (between harvest and emergence of 

autumn-planted crops). 


39 



Plant damage symptoms include leaf curl and 

discolouration, as well as white and purple streaks 

along the veins. RWA prefers to live in leaf whorls and 

tightly rolled leaves, thus damage begins at the base 

and progresses towards the tip of the leaves. Often the 

leaves will lay prostrate on the ground. Later infestations 

can cause damage to the flag leaf which curls, trapping 

the awn and preventing the head from completely 

emerging. This produces a ‘gooseneck’ head and as a 

result, the grain does not properly mature. Heads can 

also appear bleached. 


A rapid response to detection of potential exotic pests 

can be the key to containment, eradication or 

management. If you see anything unusual, call the 

Exotic Plant Pest Hotline on 1800 084 881. 

Speak to your state department of primary industries or 



Surveillance 

One of the best ways to identify if RWA is present in the 

field is to look for the damage symptoms listed above. 

These symptoms can also be caused by other diseases 

and disorders such as herbicide and virus damage, 

nutrient deficiencies and frost. It is important to identify 

these symptoms in conjunction with the presence of 

aphids to be more confident in the diagnosis. 


the chance of successful eradication and reduce the 

cost and social impact of an incursion. 

Incorporate surveillance for exotic pests when undertaking 

routine crop monitoring and other crop detection and 

measurement activities. 

40 











www.planthealthaustralia.com.au/biosecurity/ 

grains 

Ute Guides, Southern (p. 171)/ Western (p.138).

CANOLA APHIDS 

Cabbage aphid (Brevicoryne brassicae), Turnip aphid (Lipaphis erysimi) and 

Green peach aphid (Myzus persicae) 


10 mm 20 

Cabbage aphid 

adult 

30 

for all species 

Dark 

head and 

thorax 

Turnip aphid 

Dull greygreen 

in 

colour 

Tips of 

siphuncles 

do not reach 

base of 

cauda 

Form dense colonies 

(appear bluish grey) 

with a fine, whitish 

powder covering. 

Often found on flowering 

spikes and early pods 

Green peach aphid 

Dark bars on 

abdomen (dorsal) 

of adults and 

later instars 

Dark abdominal 

patch on winged 

adults 

Pale yellowgreen, 

green, 

orange or pinkish 

in colour 

Tubercles 

turned 

inwards 

Oval-shaped 

Siphuncles longer 

than cabbage and 

turnip aphids 

Tips of 

siphuncles 

nearly reach 

base of 

cauda 

Form dense colonies 

with a WAXY covering 

(less pronounced than 

powdery cover of 

cabbage aphids). Often 

found on flowering spikes 

and early pods 

Mainly found sparsely 

distributed on 

undersides of leaves 


41 



Cabbage, turnip and green peach aphids can be 

confused with each other and some pulse aphids. 


Cabbage and turnip aphid infestations occur most 

frequently from early flowering to late pod development. 

They are most prolific in autumn and spring when the 

warm weather enables them to rapidly multiply. Rates 

of development reduce over winter. Canola is most 

vulnerable to aphid damage during bud formation 

through to late flowering. The cabbage aphid is more 

tolerant of cold weather than the turnip aphid and will 

continue to develop slowly at temperatures around 

5-9 o C. 

Green peach aphids are most common in autumn and 

seldom cause economic loss to canola crops. However, 

they are an important vector of plant diseases such as 

cucumber mosaic virus, bean yellow mosaic virus and 

beet western yellows virus in canola (see p. 36). 


Cabbage and turnip aphid host plants are generally 

restricted to the crops and weeds belonging to the 

cruciferous plant family. 

Green peach aphid may also cause indirect damage by 

spreading plant viruses. 

Heavy infestations, particularly at flowering, can lead to 

large amounts of honeydew and black sooty mould. 

Cabbage and turnip aphids usually form dense colonies 

on the floral parts, especially at the maturing, terminal 

flowering spike. Colonies on leaves often become 

evident by the distortion and discoloration (yellowing) 

of infested parts. Younger developing plant parts are 

preferred to older senescing parts. 

Green peach aphids are usually found on the lower 

surface of basal, senescing leaves. They do not generally 

form dense colonies or cause leaf distortion. Large 

numbers occasionally occur on young, vegetative 

canola. 


Direct visual searches, sweep netting, yellow sticky traps 

or yellow pan traps. 

Monitoring for aphids should start in late winter and 

continue through early spring with regular checks at 

the most vulnerable crop stage (bud formation to late 

flowering). 


Green peach aphids will attack many plant families 

(including broad leaf pastures, pulse crops and oilseeds). 


Aphids can cause direct feeding damage to plants, when 

in large numbers, as they remove sap. This reduces 

nutrient flow and can cause plant wilting. 


42 


For disease-prone areas (high rainfall), regular aphid 

monitoring from autumn onwards is recommended 

to detect aphids moving into crops, particularly along 

paddock edges. 

Check at least five points over the entire paddock, 

including representative parts. Visually search for aphids 

on a minimum of 20 plants at each point and count the 

number of plants infested with aphids. If more than 

20% of plants are infested, control measures should be 

considered to avoid yield losses. 


Hover fly, lacewing larvae and 

ladybirds are effective predators 

and can help suppress populations. 

Aphid parasitoid wasps (evident by 

the presence of ‘mummies’). 


Implementing early summer weed 

control in areas where aphids build 

up on alternate host plants (e.g. 

cruciferous weeds). 

Sow crops early where possible to 

enable plants to begin flowering 

before aphid numbers peak. 

Select cultivars that are less 

susceptible to aphid-feeding damage 

where possible. 

Seed treatments and border spraying 

(autumn/early winter) when aphids 

begin to colonise crop edges may 

provide sufficient control. 

Selective foliar spray (e.g. pirimicarb). 

Insecticide resistance is common in 

some Australian aphid populations. 

Chemical rotation of insecticide 

groups will reduce the onset of 

resistance.

PULSE APHIDS 

Blue green aphid (Acyrthosiphon kondoi), Pea aphid (Acyrthosiphon pisum), 

Cowpea aphid (Aphis craccivora) and Green peach aphid (Myzus persicae) 


Blue green aphid adult 

Pea aphid adult 

Cowpea aphid adult 

10 mm 20 30 

Blue green aphid 

Pea aphid 

Long 

antennae 

Dark joints 

on antennae 

segments 

Very long 

siphuncles 

(relative to pea 

aphid) 

Blue-green to 

grey-green in 

colour 

Blackish 

knee joints 

Yellow-green or 

pinkish in colour 

Cowpea aphid 


Adults black 

in colour 

Nymphs dull 

grey in colour 

Black and white 

banding on the legs 

(for all growth 

stages) 

For green peach aphid characteristics see canola aphids. 

Can be confused with other pulse and canola aphids. 

Currently there are no aphid biosecurity threats for 

pulses. 


Pulse aphids are common in winter and spring and are 

usually found on the upper part of the plants, particularly 

growing points. 

Virus management is critical for disease-prone areas (see 

monitoring/sampling overleaf) as these pulse aphids 

can transmit plant viruses and diseases. 


43 



These aphids are commonly found on all pulses 

including field peas, lupins, lentils, faba beans and 

other legumes. 

Blue green aphids are also found on annual medic, 

subterranean clover pastures and vetch. 


Aphids can cause direct feeding damage to plants when 

in large numbers as they remove sap, which can cause 

wilting of plants. Aphids also cause indirect damage by 

spreading plant viruses that they take up and pass on 

when sucking sap from infected plants and then feeding 

on uninfected plants. 

Heavy infestations deform leaves, growing points and 

stunt plants. At flowering, heavy infestations can lead to 

large amounts of honeydew and black sooty mould. 


Direct visual searches and counts, sweeping netting, 

yellow sticky traps or yellow pan traps (can assist in early 

aphid detection). 

For disease-prone areas (high rainfall), regular 

monitoring for virus management is critical in pulses. 

Minimising the virus source, sowing seed that is virusfree, 

managing crop agronomy (to reduce aphid landing 

sites) and monitoring for early detection are some key 

management strategies. 

Regular monitoring for aphids should start in autumn 

and continue through to early spring with several checks 

a week at the most vulnerable crop stage (bud formation 

to late flowering). 

Check at least five points over the entire paddock 

including representative parts. Visually search for aphids 

on a minimum of 20 plants at each point and count the 

number of plants infested with aphids. If more than 

20% of plants are infested, control measures should be 

considered to avoid yield losses. 




Hover fly, lacewing larvae and 

ladybirds are effective predators 

and can help suppress populations. 

Aphid parasitoid wasps (evident by 

the presence of ‘mummies’). 

Ute Guides, Southern (pp. 75-78)/Western (pp. 54, 57, 58, 60). 

44 


Implementing early summer weed 

control on your property where 

aphids build up on alternate host 

plants (e.g. broad leaf weeds). 

Sow crops early where possible to 

enable plants to begin flowering 

before aphid numbers peak. 

Select cultivars that are less 

susceptible to aphid feeding damage. 

Ensuring rapid development of dense 

crop canopy so that bare ground is 

covered will assist in deterring aphid 

landings. 

Narrow rows with high seeding rates 

can assist. 

Selective foliar spray (e.g. pirimicarb). 

Seed treatments. 

Border spraying (autumn/early 

winter) when aphids begin to 

colonise crop edges may provide 

sufficient control. 

Insecticide resistance is common 

in many Green peach aphid 

populations. Chemical rotation of 

insecticide groups will reduce the 

onset of resistance.

Hemiptera: Scutelleridae 

Sunn pest (Eurygaster integriceps) 




adult 

10 mm 

20 

30 40 50 

Adult 

Colour varies from 

greyish-brown to 

reddish-brown 

Wide oval-shaped 

body with a wide 

triangular head 

Wings completely covered by a 

hardened shield (scutellum) 

with a rounded bottom edge 

Eggs 

Piercing 

and sucking 

mouthpart 

Nymphs 


Rounder in shape 

than adults, five 

nymphal stages 

The Sunn pest can be confused with other true bugs such 

as stink bugs (Pentatomidae), seed bugs (Lygaeidae) and 

other shield bugs such as the predatory glossy shield 

bug (Cermatulus sp.). A distinctive character of the Sunn 

pest is the wing covering (scutellum) which completely 

hides the wings. This feature is not seen in the other two 

bug families nor in predatory shield bugs. 

Spherical (about 1 mm in diameter). 

Shiny light green in colour, 

laid in two even rows (raft) 


The Sunn pest is widespread in Bulgaria, Greece, 

Romania, Southern Russia, Iran and Israel. It is also 

present in other European and Asian countries. 

Adults have functional wings and can actively disperse 

and migrate long distances (>250 km). 

The Sunn pest has one generation per year and 

individuals can survive for up to one year depending on 

temperature and fat reserves. 

The egg and diapause stages can survive without host 

plants for long periods in cracks in the soil and therefore 

can be spread through soil contamination in machinery 

and equipment. 


45 



The Sunn pest attacks a variety of cereal crops such as 

wheat, barley, oats, sorghum, rye, durum millet and 

corn. It can also feed on wild cereal grasses. 


Sunn pests predominantly attack leaves, stems and 

grain, reducing yield and quality. Young instars feed on 

buds and leaves, hiding deep in the plant canopy. Older 

instars and adults feed on developing grain and are 

capable of feeding on dry grain if water is available. 

Infested cereal crops display yellowing and dieback 

of the leaves, stems and entire plant. Stunting and 

abnormal flower formation and discolouration 

(whitening) can also occur. Cereal grains may be aborted 

if feeding occurs before grain development. Feeding on 

developing seeds can result in shrivelled, discoloured 

(white) and empty heads. The Sunn pest injects toxic 

enzymes into the seed during feeding and, as a result, 

the grain flour has a foul smell and the quality of baking 

dough is substantially reduced. 

Surveillance 

Winter and spring cereals should be targeted for 

surveillance of the Sunn pest. 

Any insect that resembles this bug must be sent to a 

specialist for identification. 




management. If you see anything unusual, call the Exotic 

Plant Pest Hotline on 1800 084 881. 












www.planthealthaustralia.com.au/biosecurity/ 

grains 

Ute Guides, Southern (p. 181)/ Western (p.148). 








46 


DAMSEL BUGS OR NABIDS Hemiptera: Nabidae 

Damsel bugs or Nabids (Nabis kinbergii) 


BENEFICIAL 


adult 

10 mm 

20 

30 40 50 

Nymph 

Undeveloped wings 

(wing buds) 

Adult 

Narrow 

elongated 

head 

Curved 

beak 

(mouthpart) 

Large and well 

developed eyes 

Pale brown colour. 

Slender streamlined 

body 

Long antennae 

and legs 

Fully developed 

wings on adult 


47 


Lifecycle 


Adults have a slender pale brown body with a narrow 

head, large protruding eyes and long antennae. Damsel 

bugs move quickly when disturbed. Juveniles are similar 

but smaller in size. 

Damsel bugs can have multiple generations per year 

with each generation lasting around 4-5 weeks in warm 

conditions. 

Females insert their eggs into leaves or plant stems. 


Damsel bugs are common throughout most of Australia 

and can generally be found in the canopy of crop plants 

with an abundance of prey. They are prevalent in spring 

to autumn and adults can live for a few weeks. 


Adults and nymphs are predatory and feed on a range 

of prey including caterpillars, aphids, leafhoppers, mirids 

and moth eggs. In particular, damsel bugs are considered 

to be effective predators of diamondback moth. 

Ute Guides, Southern (p. 141)/Western (p.119). 


Damsel bugs can sometimes be mistaken for other bugs 

such as mirids but they differ by having a long snout 

(proboscis) that is fine, curved and carried under the 

body when not feeding. They also appear similar to 

assassin bugs, although these have a concave abdomen 

(when viewed from above) and are less widely distributed 

than damsel bugs. 

The mouthparts fit into a groove under the body. 


48 


PREDATORY BUGS Hemiptera: Heteroptera 

Predatory shield bugs (Pentatomidae) 

Assassin bugs (Reduviidae) 


BENEFICIAL 


adult 

10 mm 

20 

30 40 50 

Spined predatory shield 

adult 

Assassin 

Spined predatory shield bug 

Assassin bug 

Adult Nymph Eggs 

Narrow, 

elongated 

head 

region 

Prominent spines 

on shoulders 

(thorax) 

Lifecycle 


There are many different species and although these 

differ widely in their lifecycles, most species have 

multiple generations per year. Species that may be found 

in broadacre crops are assassin bugs, the glossy shield 

bug (Cermatulus nassalis) and the spined predatory 

shield bug (Oechalia schellenbergii). 

Predatory bugs are typically prevalent in spring through 

to autumn. Adults usually live for several months. They 

lay their eggs in batches or rows on plant material or the 

soil surface. 


Lack of wings 

in nymph 

Predatory shield bugs can easily be mistaken for pest 

shield bugs, such as the brown shield bug. Shield bugs 

are larger in size than other pest sucking bugs such as 

rutherglen bugs and mirids. The spined predatory shield 

bug is easily recognised by the large spines on its thoracic 

region. Assassin bugs are similar to damsel bugs. 

Eggs have ‘eyelashes’ 

and laid 

in batches 


Long antennae and legs. 

Large and well developed eyes. 

Piercing/sucking 

mouthparts (beak) 

Predatory shield bugs are common throughout most 

of Australia and are often found in the canopy where 

there is an abundance of prey. Assassin bugs are more 

common in tropical crops. 


Adults and older nymphs are predatory, feeding on a 

range of prey including moth larvae, eggs, aphids, mites 

and other insects. Some assasin bugs just attack spiders. 

Species vary in the size and type of prey they are able to 

capture, but all use piercing mouthparts to suck out the 

body contents of their prey. Some inject a toxin to help 

break down the cellular material. 

Ute Guides, Southern (pp. 142-144)/Western (pp. 117, 118, 120). 


49 


FLIES (Order Diptera) 

Diptera - di (two); ptera (wings) 


Adult 

Antennae 

thread-like in 

females 

Antennae brushlike 

in males 

Modern antennae - 

hair-like structure 

(arista) 

Piercing 

and sucking 

mouthpart 

*Six legs 

Sponging 

mouthpart 

*Compound 

eyes 


50 

Primitive 

adult form 

Larva 

Mouth 

hook 

Breathing hole 

(prothoracic 

spiracle) 

* Indicates character for all species 

Source: Modified from Peterson (1960) and CSIRO (1991) 


Head 

capsule 

*One pair 

of wings 

(forewing) 

*Reduced 

knob-like 

hindwings (halteres) 

just behind forewings 

Tapering 

head region 

Legless 

Setae 

Modern 

form 

Modern 

form 

Primitive 

form

Larvae 

Larvae are legless and can be variable in form. Primitive 

forms can have a sclerotised head capsule and nonjointed 

legs. Larvae of more evolved fly groups do not 

have a distinct head capsule and the head region has 

mouth hooks. 

Adult 

Small to medium in size, only one set of wings (forewings) 

and hindwings reduced to halteres (balancing organs). 

Lifecycle 


The eggs are usually laid into a suitable food source. The 

larvae complete their development and pupate in the 

substrate where eggs were laid. This can be soil, organic 

matter, water, plant tissue or animal tissue. 


cropping 

Gall midges or gall gnats (F: Cecidomyiidae): This 

family includes the biosecurity threats, Hessian fly and 

Barley stem gall midge. These are covered in this section 

on page 52. Some gall midges predate on aphids and 

mites. 

Leaf miners (F: Agromyzidae): This family includes 

the biosecurity threats, pea leaf miner and American 

serpentine leafminer. These are covered in this section 

on page 54. 

Hoverflies (F: Syrphidae): Resemble bees superficially 

but adults have a characteristic hover behaviour in 

flight. Hoverfly larvae are predators of soft-bodied 

insects, particularly aphids. Hoverflies are discussed in 

this section on page 57. 

Feeding 

Adult mouthparts vary from sucking and/or piercing 

to biting. Most adults ingest liquid foods and digestion 

is partially external (e.g. salivary secretions are used to 

liquefy food and then the softened product is ingested). 

Some flies (e.g. mosquitoes and March flies) pierce the 

skin of their prey and suck up blood. 

Fly larvae generally feed on moist, decomposing food 

items such as carrion, fungi and rotting vegetable 

matter, although some are predators (e.g. Syrphidae) and 

parasites (e.g. Tachnidae) of other insects and animals. 


51 


GALL MIDGES OR GALL GNATS 

Diptera: Cecidomyiidae 

Hessian fly (Mayetiola destructor) & 

Barley stem gall midge (Mayetiola hordei) 




larva 

pupa 

adult 

10 mm 

20 

30 

both species 

both species 

both species 

Long filiform 

(bead-like) antennae 

Adult 

Hessian fly 

Resemble 

mosquitoes - 

slender body 

Long legs 

Halteres, 

reduced 

hindwing 

Wing venation consists 

of a few weak veins 


52 

Pupae 

Hessian fly pupae 

No galls formed when 

Hessian fly larvae reside 

within host plant 

Larvae of both species 

Legless (maggot-like) with 

13 body segments. 

Cylindrical and tapered to one end. 

Barley stem gall midge larvae 

- pale red initially and turn 

white as they mature. 

Hessian fly larvae - initially 

white then turn 

brown 


Larvae produce 

a pea-sized stem 

gall while residing 

inside the stem and 

feeding internally 

Pupae of both species known as ‘flaxseeds’. 

Dark brown in colour. 

Tapered to one end. 

Present towards harvest at 

base of host plant 

Hessian fly eggs 

Approx. 0.5 mm long. 

Elongate with rounded ends. 

Initially red in colour, then darken 

with age. Laid on upper leaf surface 

in lines parallel with 

leaf veins 

Barley stem gall midge pupae


These two closely-related species are difficult to identify 

without specialist knowledge. 

The brown ‘flax-seed’ pupae can be diagnostic in the 

field. The presence of a gall produced by M. hordei is also 

characteristic. 

Larvae can be confused with other legless maggots 

but there are no major fly larvae pests above ground on 

plants in broadacre crops in southern Australia. 

Adults can also be confused with other midges and 

mosquitoes. 


Hessian fly is widespread in Europe and has been 

recorded in the USA. It has also been detected in other 

countries including New Zealand, Africa and Russia. 

Barley stem gall midge has been recorded in Europe, 

USA, Canada and Africa. 

These species actively fly and can disperse on wind 

currents more than nine kilometres. All life stages 

(larvae, pupae and adults) can achieve long distance 

dispersal by hitchhiking on plant material (e.g. straw). 

Pupae are able to survive over long periods. 


These exotic fly pests impact on market access and 

production costs. Crop losses of up to 40% have been 

recorded for Hessian fly. 

Hessian fly: Wheat is the primary host capable of 

supporting the whole lifecycle. Alternate host plants 

include wheatgrass, rye, barley, grass weed species and 

broome. 

Barley stem gall midge: Found almost exclusively on 

barley but occasionally recorded on oat, wheat and rye. 

Due to the difficulty in distinguishing between these 

two species, the information on distribution and 

host types are limited and not absolute. 


Hessian fly larvae feed on leaves, stems and plant heads 

resulting in leaf discolouration (dark green to bluishgreen), 

stunted growth and reduced grain quality and 

yield. Larvae lodge themselves between leaf sheaths 

above nodes, while pupae are found at the base of plants 

at harvest. Control of these flies would rely on cultural 

methods and plant host resistance as most chemical 

controls are ineffective. 

Barley stem gall midge larvae feed at the base of barley 

between the leaf sheath and the stem, producing small 

characteristic pea-shaped galls. Galls are an abnormal 

outgrowth of the plant in response to barley stem 

gall midge feeding. Infestations can lead to weakened 

stems, stunted plant growth and a loss of grain quality 

and yield. Infested plants are a darker green than 

undamaged plants. 

The adults do not feed. There may be 2-3 generations 

each year. 

Surveillance 

On a symptomatic plant, separate the sheath at the base 

of the stem. You may find maggot-like larva feeding on 

the stem surface. Look carefully for a pea-shaped gall 

formation caused by Barley stem gall midge. Carefully 

split the gall and you may find the larvae inside. 







Any insect that resembles these flies must be sent to a 

specialist for identification. 


















Ute Guides, Southern (pp. 169, 170, 175)/Western (pp. 136, 137, 142). 


53 


EXOTIC LEAF MINERS 

Diptera: Agromyzidae 




adult 

10 mm 

20 

30 

Adult 

Larval damage 

Shiny black/ 

grey and 

yellow in 

colour 

One set of 

wings (forewings) 


The Agromyzidae family are a well-known group of 

small flies whose larvae feed internally on living plant 

tissue, often as stem and leaf-miners. Within Australia 

there are approximately 147 Agromyzidae species in 16 

genera. Many Australian species are still undescribed. 

Nearly all Agromyzidae species are host-specific but a 

few species are highly polyphagous and have become 

important pests of agriculture and horticulture in many 

parts of the world. 

54 

Bright yellow 

marking on 

base of thorax 

(scutellum) in 

most species 


Characteristic leaf mining 

(tunnelling) from larvae 

feeding in plant tissue 

Tunnels usually whitish in colour with 

dried cut brown areas that thicken as larvae 

mature. Tunnels can be tightly coiled, linear, 

serpentine or irregular shaped 

Key exotic agromyzid species for Australian 

agriculture include: 

American serpentine leaf-miner (Liriomyza trifolii) 

Pea or serpentine leaf-miner (Liriomyza huidobrensis) 

Pea leaf-miner (Chromatomyia horticola) 

Chickpea leaf-miner (Liriomyza cicerina) 

Diagnostic characteristics are dealt with at the family 

level due to the difficulty in separating these species.

Eggs are laid just below the leaf surface and larvae feed 

internally on the plant in which the eggs were laid. The 

number of eggs laid varies according to the host plant 

and temperature. 

Larvae (maggots) are legless, typically cylindrical in 

shape and tapering at the head region. There are three 

larval stages that feed within the leaves (beneath the 

surface) creating a winding tunnel or ‘mine’. They 

occasionally feed on the outer surface of young pods. 

The larvae of Liriomyza spp. leave the plant to pupate, 

so pupae may be found in crop debris, in the soil or 

sometimes on the leaf surface. In contrast, pea leafminer 

(C. horticola) larvae pupate inside the leaf at the 

end of the larval mine. 

These closely-related species are difficult to tell apart 

and identification requires specialist knowledge. 

These biosecurity threats can be confused with native 

leaf-miner species. Most of these are host-specific but 

they are not well known, and as many species remain 

undescribed, they should be sent for identification. 

The occurrence of leaf mining (tunnelling) can be easily 

recognised in the field. 


L. trifolii: beans, peanuts, soybeans, lentils, lupins, faba 

beans and chickpeas. 

L. huidobrensis: beans, lupins, field peas and faba beans. 

C. horticola: sunflower, field peas, canola, lentils, 

lupins, chickpeas and other Brassicaceae, Fabaceae and 

Asteraceae plants. 

L. cicerina: chickpea, sweet clovers, disk trefoil and 

Ononis species. 


Typical leaf miner damage includes leaf destruction (leaf 

wilt, desiccation and premature fall) and retarded plant 

growth. Plant damage in the form of stippling can also 

be caused by females puncturing leaves for sap-feeding 

and egg-laying (oviposition). Plants can also suffer from 

secondary attack when pathogenic fungi enter the leaf 

through puncture wounds. Mechanical transmission of 

plant viruses can also occur. Severe infestations can lead 

to total crop loss due to both larval-mining and leafpuncturing. 

Most leaf mines are greenish in colour at first, turning 

whitish over time. Leaf mines wind irregularly through 

the leaf and increase in width as larvae mature. 


L. trifolii is present in Europe, Asia, Africa, Central 

America and the Caribbean, North and South America 

and Oceania. 

L. huidobrensis is widespread through Africa, Asia, 

Central America, Europe, Canada and the USA. 

C. horticola is widespread in Africa, Asia and Europe. 

L. cicerina is found in Africa and Europe. 

Agromyzid flies are not very active flyers and tend to 

remain close to their target crops, often only moving 

very short distances between host plants within a crop. 

They can move longer distances if carried by wind. 

Entry of these invasive agromyzids (apart from L. cicerina) 

is likely to be via imported plant material containing 

leaves, particularly seedlings or propagation material 

where eggs have been deposited. 

If eggs have not yet hatched and no signs of mining 

are visible, the eggs may survive treatment at port 

of entry. Initial incursions are likely to arise from 

horticultural areas, and grains industries will face 

secondary attack from these horticultural incursions 

if eradication is not achieved. 

Mine shapes in the leaf tissue can vary depending on 

the species and can be narrow and linear with anterior 

spiracles (e.g. C. horticola), linear and shallow on the 

upper leaf surface (e.g. L. trifolii), serpentine in shape 

(e.g. L. cicerina) serpentine or irregular in shape (e.g. L. 

huidobrensis) or have distinctive trails of frass deposited 

in black strips on the sides of the mine (e.g. L. trifolii). 

Surveillance 

While fully-formed leaf mines should be readily visible to 

quarantine officials, signs of early infestations are much 

less obvious and can be easily overlooked. 

Any leaf-mining damage or insect that resembles these 

flies must be sent to a specialist for identification. 








55 





















56 


HOVERFLIES Diptera: Syrphidae 

Various species - approximately 170 species. 


BENEFICIAL 


larvae 

10 mm 

20 

30 

adult 

Adult 

Hair-like 

antenna 

Hair-like 

antenna 

Metallic sheen 

on thorax 

Large 

compound 

eyes 

Larva 

One set 

of wings 

(forewings) 

Green to 

brownish colour. 

Dominant whitish 

stripes down 

centre 

Black and yellow 

(bee-like) 

colouration 

on abdomen 

Legless (maggotlike) 

- no true legs or 

prolegs 

Flattened 

(dorsal-ventral) 

body 

Pointy 

head region 

with mouth hook 


57 


Lifecycle 


Adult hoverflies have dark-coloured flattened bodies 

with black and yellow markings. 

Larvae are legless, green in colour and appear grub-like. 


Some species superficially resemble bees as they hover 

near plants and have similar colouration. They differ 

from bees in having only one set of developed wings 

and their movement is faster and more direct than bees. 

They can also be confused with other flies. 


Larvae attack a range of soft-bodied insects but prefer 

aphids. They spear prey with their mouth hooks, 

often holding them upright and sucking out the body 

contents. Adults feed on pollen and honeydew and are 

not predatory. 

The adult fly can often be seen hovering near flowers 

searching for nectar and a place to lay eggs. These are 

usually placed near prey (e.g. aphid colonies) for the 

newly hatched larvae to feed on. 

Ute Guides, Southern (p.140)/Western (p.116). 


Hoverflies are common throughout most of Australia, 

can be found in a variety of habitats and are often 

associated with aphid populations. They are common 

in flowering crops such as canola, pasture paddocks 

and on some flowering roadside weeds. Some species 

can be found throughout summer months in irrigated 

paddocks. They are most prevalent in spring. 


58 


EARWIGS (Order Dermaptera) 

Dermaptera - derma (skin or covering); ptera (wing) 

There are at least 63 species of earwigs present in Australia. 


Adult and juvenile forms 

Earwigs are a distinctive group of insects of small to 

medium size (5-50 mm in length) that are mostly dark 

coloured (brown to black), have chewing (mandibulate) 

mouthparts and moderately long bead-like (filiform) 

antennae. Both adults and nymphs are similar in 

appearance but nymphs are smaller and paler than adults. 

Earwigs are usually easily identified by their hardened 

pincers (cerci) or claw-like structures at the rear of their 

flattened, elongated bodies. Both sexes have these 

pincers, but in males they are large and curved whereas 

in females they are mostly straight with slightly inward 

pointing tips. These sexual characteristics relate to all 

earwig species. 

Earwig families relevant to broadacre 

Forficulidae: This family has three native Australian 

species and the introduced European earwig Forficula 

auricularia, which has become a troublesome pest 

within localised areas. 

Labiduridae: This family consists of relatively primitive 

earwig species that are generally red-brown in colour 

and range from 10-45 mm in length. Members of this 

family are found all over Australia. The native earwig, 

Labidura truncata, is by far the most common species, 

particularly in sandy habitats. 

Most species of earwigs are wingless. Those with wings 

have clear (membranous) hind wings folded in a fan-like 

way and hidden beneath a protective, hardened and 

short covering (forewing or tegmina). 

Lifecycle 


Earwigs mate end to end, often grasping each other’s 

pincers. Unlike most insects, female earwigs have a 

maternal instinct and care for their young. They lay 20- 

80 white eggs in clusters, usually within tunnels dug 

especially for this purpose. The eggs hatch over a 2-3 

week period before turning into nymphs. Immature 

nymphs are paler in colour and take four or more moults 

before developing into an adult. 

Habitat 

Earwigs are nocturnal but are attracted by lights and 

can become unwelcome visitors to houses. The majority 

of earwigs are found during the day in dark, sheltered 

environments and are common under rocks, wood, tree 

bark, stones, stubble or other plant residues. 

Most species are omnivores, feeding mainly on decaying 

plant material but occasionally on dead creatures. They 

sometimes feed on live insects and can be seen using 

their rear pincers to carry their prey after it has been killed. 


59 


EARWIGS Dermaptera 

European earwig (Forficula auricularia) and 

Native earwigs (Labidura truncata, Gonolabis michaelseni, Forniculina spp. and others) 


European earwig 

10 mm 

20 

30 40 50 


Short 

forewings (tegmina) 

Yellow 

‘shoulders’ 

Uniform dark 

coloured body 

Legs and pincers 

are a lighter 

colour than the body 

Male – 

long and curved 

pincers 

Female – 

straight pincers 

Native earwig 


Male – 

long and curved 

pincers 

60 

Native earwig 

Male pincers - long and slender 

with a distinctive tooth near the middle 

of the inner edge 


Wingless 

Generally lighter 

body foreparts and 

darker abdomen 

Female – 

straight pincers 

Dull brown with 

straw coloured 

markings 

Legs and pincers 

are similar in colour 

to parts of the body 

Orange 

triangle on back

Damage symptoms: 

shredded leaf tips or jagged 

holes in the leaves are typical of 

earwig damage. 


Native earwigs and the European earwig are similar to 

other earwig species. Earwigs are sometimes confused 

with staphylinid beetles, but they can be distinguished 

from the latter by the presence of pincer-like cerci. 


European earwigs are an introduced pest into Australia 

and were first recorded around 1930. They were recorded 

as crop pests in WA in the early 1990’s and have since 

been spreading, although their distribution appears to 

be patchy and isolated. They are also commonly found 

in eastern Australia. 

The European earwig’s native climate is cool and relatively 

humid. Although adults have wings, they rarely fly and 

are mainly spread to new areas and crops by human 

activity. They can be transported in contaminated seed, 

pot plants, cardboard boxes, machinery and vehicles. 

Once introduced, earwigs slowly spread from the 

original infestation to neighbouring properties. 

Crop and pasture residues on the soil surface enhance 

earwig survival and breeding, allowing large populations 

to build up during autumn and early winter. Crops and 

pastures sown into these high risk paddocks are most 

vulnerable to attack by pest earwigs. 

Native earwigs are widespread throughout Australia. 

They are generally found either individually or in 

low numbers under rocks or wood. This contrasts to 

the European earwig which is more commonly seen 

congregating in high numbers. Native species rarely 

exceed 40 mm long and are generally elongated, 

flattened and have smooth, shiny bodies that are mainly 

brown to black in colour. 

Labidura truncata is a common large native earwig 

(about 35 mm) that is considered beneficial because 

of it’s preference to feed on caterpillars and other softbodied 

invertebrates. It captures prey with its pincers 

and holds them while feeding. 


European earwigs attack a variety of crops. Crop 

seedlings, particularly canola, cereals and pulse crops 

are the most susceptible. 

Native earwigs are omnivorous, eating a wide variety of 

plant and animal material and they are rarely known as 

crop pests. Many species live primarily on a diet of plant 

matter, both living and decaying. They also consume 

dead insects and other organisms. 


European earwigs often feed at night, starting along 

paddock edges and moving deeper into the crop with 

time. Shredded leaf tips or jagged holes in the leaves 

are typical of earwig damage. In severe infestations, 

European earwigs can completely defoliate young 

seedlings leaving only stems or bare ground in 

the crop (which corresponds to the highest earwig 

populations). 

European earwigs may become a contaminant of 

harvested grain. They shelter in crop windrows (swaths) 

and may be collected with the seed at harvest. If earwig 

numbers are high, the harvested grain may be rejected 

or require cleaning, ultimately reducing profits. 

Native earwigs rarely cause crop damage to southern 

Australian grain crops. 


61 



Inspect establishing crops with bare or thinning patches. 

Look under wood, rocks and plant residues for earwigs. 

Inspect paddocks on warm, moist nights using a torch to 

detect feeding earwigs. Carpet squares, tiles or terracotta 

pots can be left out for several nights in suspected risk 

areas and then inspected for earwigs that may shelter 

beneath these refuges. 



All earwigs will predate on 

themselves. 

Stubble management and cultivation 

will reduce earwig breeding sites. 

Carbaryl is registered for control of 

earwigs in some situations. 

Pest numbers of earwigs may be 

controlled by high populations of 

carabid beetles. 

Various vertebrate pests such 

as birds and lizards will feed on 

earwigs. 

Burning stubbles has shown some 

success. Early season burning is 

preferable. Aim for an even paddock 

burn or patch burn known affected 

areas. 

Note: burning may not be the 

preferred option because of the risk of 

wind erosion. 

Grazing pasture paddocks to below 

1.5 t/ha of feed on offer in spring will 

reduce earwig numbers. 

Insecticide seed dressings may also 

give some control of moderate pest 

levels. 

Baiting with a mixture of cracked 

wheat, sunflower oil and chlorpyrifos 

has had some success. Best results 

are obtained in autumn before 

alternative food sources are 

available. 



62 


Early season weed control of affected 

paddocks, fence-lines, rock-heaps or 

other habitats will help to minimise 

survival.

SPRINGTAILS (Class Collembola) 

Collembola: Sminthuridae 

Lucerne flea (Sminthurus viridis) 


adult 

10 mm 

20 

30 

Colour variations - 

light yellow brownishgreen 

with irregular 

darker patches 

Segmented 

antennae 

Globular shape - 

soft bodied 

The lucerne flea is a collembolan (springtail), included in 

a group of arthropods that have six or fewer abdominal 

segments and possess a tubular appendage. In sheer 

numbers, Collembola are one of the most abundant of 

all macroscopic animals. 

Jumping structure 

(furcula) normally 

tucked under body 

(rear end) 

Damage symptom: 

transparent windowing of 

leaves (originating from 

the underside) 

Newly hatched 

nymphs (about 0.75 mm 

long) are pale yellow in 

colour 

They are frequently found in leaf litter and other decaying 

material, where they are primarily detritivores. Only a 

few species, including the lucerne flea, are regarded as 

crop pests around the world. 


63 



Lucerne flea can be confused with other globular type 

springtails. 


Typically found throughout the winter rainfall areas of 

southern Australia, including Tasmania. Although lucerne 

fleas are widespread and commonly encountered, they 

are often sporadically distributed within a particular 

region. 

Lucerne flea are commonly observed in paddocks with 

a heavy soil type (e.g. clay/loam) and are less frequently 

found on sandy soils. 

Crops and pastures are most susceptible around the 

time of emergence. 


Lucerne fleas have a tendency to feed on broadleaf 

plants including clovers, medics, lucerne, serradella 

and capeweed. They can also cause damage to canola, 

ryegrass, wheat and barley but these appear to be nonpreferred 

hosts. 


Lucerne fleas feed by removing the epidermal cells of 

plants and feeding on the soft tissue underneath, leaving 

behind the fibrous veins joined by a thin layer of leaf 

membrane. This results in the characteristic appearance 

of feeding ‘windows’. 


Lucerne fleas are easily detected as they spring off 

vegetation when disturbed. Feeding damage is very 

noticeable when lucerne fleas are present in high 

numbers. Susceptible crops and pastures sown in 

paddocks where lucerne fleas have previously been a 

problem should be checked regularly between autumn 

and spring. 




Pasture snout mite (Bdellodes 

lapidaria) and the spiny snout mite 

(Neomulgus capillatus). 

Several ground beetles and spiders 

are also known to prey upon 

lucerne fleas. 

Ute guides, Southern (p. 89)/ Western (p. 70). 

64 


Grazing management in spring. 

Weed control (particularly capeweed), 

cultivation and crop rotations 

can prevent build up of lucerne flea 

numbers. 

Spot spraying or border sprays. 

Avoid most synthetic pyrethroid 

sprays as these are ineffective against 

lucerne flea. 

Control lucerne flea in the season 

prior to sowing susceptible crops.

SLUGS & SNAILS (Order Pulmonata) 

Gastropod - gastro (stomach); pod (foot) 

The phylum Mollusca is divided into six classes of which 

the Gastropoda contains the only land-based molluscs. 

There are about 36 gastropod families in Australia. 


Adult and juvenile forms 

Gastropods have an unsegmented soft-body that 

commonly has an external (or internal) calcareous shell. 

All gastropods have a well-developed head at one end 

of the foot with eyes and 1-2 pairs of tentacles. The body 

and internal organs are twisted back so that the stomach 

lays above the large fleshy foot, hence the name 

‘stomach foot’. Gastropods move by gliding along a 

surface of mucus or slime that is produced from glands 

on the foot. 

Lifecycle 

Most gastropods are hermaphrodites, which means they 

have both male and female reproductive organs within 

the same body. Eggs are usually laid in crevices in the soil 

or under rocks but some species dig holes in the soil, lay 

eggs into the cavern, then cover the hole with soil. 

Habitat 

Gastropods favour moist environments and are usually 

found under logs and rocks, in leaf litter or under tree 

bark during the day, and move about and forage in more 

favourable conditions at night. Slugs are particularly 

susceptible to drying out and some snails enter 

aestivation (shell sealed with a thickened mucus layer to 

conserve moisture ) to survive hotter periods. 

All gastropods feed using a radula, which is a tonguelike 

structure covered by rows of rasping teeth. Most 

gastropods feed on fungi, algae and dead organic matter 

but some can also damage young crops and pastures. A 

few are carnivorous and may prey on other snails. 

Generalised shelled gastropod 

Protoconch 

Source: Modified from Smith and Kershaw, 1979 

Generalised slug 

Body 

whorl Keel Mantle Eye 

Aperture 

Umbilicus 

Columellar 

plait 

Foot 

Breathing 

pore 

Source: Modified from Smith Lucid Key 

Tentacle 


65 


ROUND SNAILS Helicidae 

White Italian snail (Theba pisana) and 

Vineyard or common snail (Cernuella virgata) 


White Italian snail 

Vineyard snail 

10 mm 20 30 40 50 

10 mm 20 30 40 

White Italian snail 

Vineyard or common snail 

White coiled shell 

with broken brown bands. 

Some lack banding 

Umbilicus is 

semi-circular 

or partly 

closed 

White coiled shells 

with almost continuous 

brown bands. 

Some lack banding 

Open circular 

umbilicus 



These snails are similar to and can be easily confused 

with other round snail species. 


Round snails are an important pest of crops and 

pastures across southern Australia, particularly where 

conservation farming involves stubble retention, 

reduced burning and reduced tillage. Crops and pastures 

grown on calcareous and highly alkaline soils are highly 

susceptible. Crops are most vulnerable at emergence 

and early development. 

Snails can be active all year round with a small amount 

of moisture and cool conditions. Snails are least likely to 

be active in hot, dry conditions, particularly in late spring 

and early summer. 


All crops and pastures can be attacked. Emerging and 

young plants of crops and pastures. Barley, canola, and 

pulse crops are most susceptible. 

66 



Round snails can shred leaves and defoliate young 

plants, due to their rasping action when feeding. Round 

snails are a grain contaminant. During extended periods 

of inactivity (aestivation) snails can be found resting 

above ground on stems, stubble and fence posts. 


Monitor all year round to allow for full use of all available 

control options. Monitor using a 0.1 m 2 quadrat, 

counting all the live snails found within the quadrat on 

the ground. Separate round from conical snails and split 

snails into two size groups, 7 mm and larger and < 7 mm, 

using a sieve. Snails < 7 mm in diameter are unlikely to 

be controlled successfully by baits.


Thresholds for control options: 

• Cereals at seedling growth stage - 20 snails/m 2 

• Pulses and canola at seedling - 5 snails/m 2 


Carabid beetles are known 

predators and can help suppress 

populations. 

Stubble management includes 

cabling, rolling and slashing. Use these 

techniques post harvest, after midmorning 

on hot days over 35 o C. Ideally 

this should be done when several 

hot days will follow. Control summer 

weeds prior to stubble management. 

Around 50-90% kill can be achieved 

when temperatures are over 35 o C. 

This is less effective in dense cereal 

stubbles. 

Burning is best undertaken early in the 

burn season. Aim for an even paddock 

burn. Around 80-100% kill can be 

achieved with an even burn and about 

50-80% kill with a patchy burn. 

Note the potential risk for soil erosion 

with these methods. 

Summer weed control especially along 

fence lines and borders. 

Molluscicidal baits can be used 

effectively in autumn to control 

mature snails across the whole 

paddock. Start baiting when 

moisture triggers snail activity in 

autumn and before significant egglaying. 

Repeat applications may be 

needed after monitoring. Around 60- 

90% kill can be achieved depending 

on timing, snail activity and bait 

application rate. 

Fence line and border baiting can be 

effective after autumn rains when 

snails are moving from aestivation 

sites. 

Ute Guides, Southern (pp. 92-93)/ Western (pp. 72-73). 


67 


CONICAL SNAILS Helicidae 

Small pointed snail (Prietocella barbara) and 

Pointed or conical snail (Cochlicella acuta) 


Small pointed snail 

Pointed snail 

10 mm 20 30 40 50 

10 mm 20 30 40 

Small pointed snail 

Pointed or conical snail 

three or 

three 

Fawn, grey or 

brown conical 

shells 

Ratio of shell length 

to its base diameter 

is always 

two or less 

Fawn, grey or 

brown conical 

shells 

Ratio of shell length 

to its base diameter 

is always greater 

than two 



These snails can be confused with each other as well as 

native conical snail species. 


Small pointed snails favour areas of rainfall higher than 

500 mm. Crops and pastures grown on calcareous and 

highly alkaline soils can be highly susceptible. Smaller 

snails can be a contaminant of canola and cereal grains. 

Conical snails are found in the highest concentration 

on the Yorke Peninsula, SA but scattered populations 

can be found in other parts of SA, Victoria, NSW and 

WA. The pest status of this species comes from being a 

contaminant of grain, particularly barley. Conical snails 

over-summer under stones and stumps, and on posts 

and vegetation. Numbers can build up in the pasture 

phase of cropping rotations. 

68 



Conical snails are mainly a pest of crops at harvest when 

they can contaminate grain and seed. 

Small pointed snails are a pest of pastures, lucerne, 

canola, and some pulses across southern Australia, 

particularly where conservation farming involves 

stubble retention, reduced burning and reduced tillage. 

Conical snails are rarely recorded directly feeding on crops 

and pasture as these snails prefer dead organic material. 


Small pointed snails may eat seedlings off at ground 

level when snail numbers are very high. 

Conical snails prefer dead organic material and therefore 

have limited impact on the crop directly. 


Monitor all year round to allow for full use of all available 

control options. Monitor using a 0.1 m 2 quadrat, counting 

all the live snails found when the quadrat is placed on 

the ground. Separate round from conical snails and split 

snails into two size groups, 7 mm and larger and < 7 mm, 

using a sieve. Snails < 7 mm in diameter are unlikely to 

be controlled successfully by baits.


No thresholds established for conical snails. 

See round snail thresholds as a guideline. 




populations. 

A parastic fly, Sarcophaga 

penicillata, is the only currently 

available biological control for the 

conical snail. Flies were released in 

2000 on the Yorke Peninsula, SA, but 

the impact on control is unclear. 

Stubble management includes 

cabling, rolling and slashing. Use 

these techniques post harvest, after 

mid-morning on hot days over 35 o 

C. Ideally this should be done when 

several hot days will follow. Control 

summer weeds prior to stubble 

management. Around 50-90% kill 

can be achieved when temperatures 

are over 35 o C. This is less effective in 

dense cereal stubbles. 

Burning is best undertaken early in 

the burn season. Aim for an even 

paddock burn. Around 80-100% kill 

can be achieved with an even burn 

and about 50-80% kill with a patchy 

burn. 

Note the potential risk for soil erosion 

with these methods. 

Summer weed control especially 

along fence lines and borders 

Molluscicidal baits can be used 

effectively in autumn to control 

mature snails across the whole 

paddock. Start baiting when 

moisture triggers snail activity in 

autumn and before significant egglaying. 

Repeat applications may be 

needed after monitoring. Around 60- 

90% kill can be achieved depending 

on timing, snail activity and bait 

application rate. 

Fence line and border baiting can be 

effective after autumn rains when 

snails are moving from aestivation 

sites. 

Ute Guides, Southern (pp. 94-95)/ Western (p. 74). 


69 


SLUGS Eupulmonata: Agriolimacidae and Milacidae 

Reticulated or grey field slug (Deroceras reticulatum) and 

Black-keeled slug (Milax gagates) 


Grey field slug 

10 mm 20 30 40 50 

20 30 40 

60 

70 

Black-keeled slug 

Reticulated or grey field slug 



Variable in colour, 

often light grey to fawn 

with dark brown markings. 

Active on soil surface 

Grey field slug 

This slug secretes a sticky milky-white coloured mucus 

over their body when disturbed (i.e. when touched). This 

can be used to distinguish them from other slugs. Grows 

up to 50 mm long. 


The body size, colour and extended keel are 

distinguishing features. 

70 

Keel (ridge) at 

posterior end 

Secretes milky 

white mucus over 

body when 

disturbed 


Uniform 

grey to black 


Prominent ridge (keel) 

along mid-dorsal line from mantle 

to tail. Keel more obvious when 

body contracts as slug is 

disturbed 

Other slugs. See Slugs: The Back Pocket Guide (GRDC 

2008). 


The grey field slug is a major pest of crops and pastures 

across southern Australia. Like all slug species it 

requires moist habitats for survival and is more likely 

to be a problem in higher rainfall areas. Crops are most 

vulnerable at establishment and damage may be more 

severe if cool wet weather slows crop growth. Heavy soil 

types, summer rains and reduced tillage are all factors 

which promote the build up of slug populations. 

The black-keeled slug is a burrowing species and as a 

result can be a more serious pest than other slug species 

in drier areas, such as South Australia, Western Australia 

and western Victoria.


Grey field slugs attack all crops and pastures but 

broadleaf plants such as canola and clovers are the most 

susceptible. 

Black-keeled slugs attack all crops and pastures but 

young canola seedlings are particularly vulnerable. 


Grey field slugs are mainly active on the soil surface and 

may eat plants off at ground level or remove irregular 

shaped areas from leaves, due to their rasping action 

when feeding. If the apical meristem and cotyledons 

of broad-leaf crops are damaged, the plants may not 

recover. 


Check paddocks prior to sowing or before crop 

emergence. This can be done by placing refuges 

which retain moisture, such as tiles, on the soil surface 

at multiple sites across the paddock. Look for slugs 

underneath refuges on moist mornings or alternatively 

monitor slugs directly in emerging crops at night when 

conditions are damp. 

Black-keeled slugs feed on the soil surface, as well as 

below the ground where they burrow down and attack 

germinating seeds. Feeding can result in the failure of 

seedlings to emerge, plants eaten off at ground level 

and irregular shaped pieces removed from leaves. In 

cereals, strips can be removed from the leaves. 





populations. 

Ute Guides, Southern (pp. 90- 91)/ Western (p. 71). 

Cultivation. 

Summer and autumn weed control. 

Seed bed consolidation (rolling). 

Rotate susceptible crops with those 

less prone to slug damage. 

Early sowing canola can help reduce 

damage. 

Molluscicidal baits can be used prior 

to or at sowing when slug numbers 

are high. 


71 


MITES (Order Acarina) 

Acarina - (akari) 


Mites are among the most diverse and successful of all the 

invertebrate groups. They have exploited an incredible 

array of habitats and, because of their small size (most 

are microscopic), go largely unnoticed. Many live freely 

in the soil or water, but there are also a large number 

of species that live as parasites on plants, animals and 

some that feed on mould. It is estimated that over 50,000 

Acarina species have been described and that a million 

or more species are currently living. 


Nymphs 

Most resemble adults but are smaller. Some juveniles 

only have three pairs of legs, gaining a fourth pair with 

their first moult. 

Adult forms 

While the appearance of mites varies widely, all mites are 

wingless. The mouth parts of mites may be adapted for 

biting, stinging, sawing, snipping or sucking. Predatory 

mites often use their chelicerae to cut through webbing 

of spider mites. Mites have four pairs of legs, no external 

segmentation of the abdomen and individuals appear 

as a single body mass. Mites do not have antennae, they 

use their pedipalps and front legs for probing. 

Lifecycle 


They can range in size from minute (0.08 mm) up to 

20 mm in length. 

72 

No antennae 

present 

Wingless 



cropping 

Redlegged earth mites and blue oat mites (F: 

Penthaleidae): These are among the most important 

pests of grain crops and pastures in southern Australia. 

They are covered in detail in this section on pages 73-77. 

Balaustium mite (F: Erythraeidae): The Balaustium mite 

attacks a variety of crops and pastures and is covered in 

detail in this section on page 78. 

Bryobia mites, two-spotted mite and the brown wheat 

mite (F: Tetranychidae): These are important pests of 

various crops. The two-spotted mite (Tetranychus urticae) 

and brown wheat mite (Petrobia latens) are small mites 

(< 1 mm in length) that are sporadic pests of cotton, 

cereals and lucerne. For further information on the twospotted 

mite refer to the Southern Ute Guide (p. 102). 

Bryobia mites are covered in detail on page 80. 

Wheat curl mite (F: Eriophyidae): The wheat curl mite 

(Aceria tosichella) is a tiny cigar-shaped mite that is the 

principal vector of the damaging cereal virus, wheat 

streak mosaic virus. For further information, refer to the 

Southern Ute Guide (p. 103). 

Chewing/sucking mouth 

parts (chelicerae) 

No external segmentation 

of body parts (fused) 

Four pairs of 

legs (adult)

Acarina: Penthaleidae 

Redlegged earth mite - RLEM (Halotydeus destructor) 


adult 

10 mm 20 30 

and 0.6 mm wide 

Eight red-orange legs 

Globular shaped, 

velvet black body 

Newly-hatched 

RLEM larvae are 

pinkish-orange 

with six legs 

Usually found in groups 

(up to 30 individuals) 

in pasture in pasture 

Damage symptom: 

silvering leaves 

(similar to frost 

damage) 

Newly-hatched redlegged earth mite (RLEM) larvae are 

only 0.2 mm long and are generally not visible to the 

untrained eye. In the following three nymphal stages, 

mites have eight legs and resemble adults, but are 

smaller and sexually undeveloped. 


Other mite pests, in particular blue oat mites and the 

Balaustium mite, are sometimes confused with RLEM 

in the field. Unlike other species that tend to feed 

singularly, RLEM generally feed in large groups of up to 

30 individuals. 


73 



The RLEM is widespread throughout most agricultural 

regions of southern Australia. They are found in southern 

NSW, on the east coast of Tasmania, the south-east of SA, 

the south-west of WA and throughout Victoria. 

RLEM are active from autumn to late spring. They are 

most damaging to newly-establishing pastures and 

emerging crops, greatly reducing seedling survival and 

development. RLEM can also cause significant feeding 

damage and a reduction in legume seed-set of pastures 

in spring. 


All crops and pastures, although canola, lupins, cereals 

and legume seedlings are most at risk. RLEM also feed 

on a range of weed species including Paterson’s curse, 

ox-tongue and capeweed. RLEM feeding reduces the 

productivity of established plants and has been found 

to be directly responsible for a reduction in pasture 

palatability to livestock. 


Typical mite damage appears as silvering or whitening 

on the attacked foliage. Mites use scissor-like chelicerae 

adapted mouthparts to lacerate the leaf tissue of 

plants and suck up the discharged sap. The resulting 

cell and cuticle damage promotes desiccation, retards 

photosynthesis and produces the characteristic silvering 

that is often mistaken as frost damage. Affected seedlings 

can die at emergence with high mite populations. 


Inspect susceptible pastures and crops from autumn to 

spring for the presence of mites and evidence of damage. 

It is especially important to inspect crops regularly in the 

first three weeks after crop emergence. Mites are best 

detected feeding on leaves in the morning or on overcast 

days. In the warmer part of the day, redlegged earth 

mites tend to gather at the base of plants, sheltering in 

leaf sheaths and under debris. When disturbed during 

feeding they will drop to the ground and seek shelter. 




French Anystis mites can suppress 

populations in some pastures. 


74 


Crop rotations with non-preferred 

crops, such as lentils and chickpeas. 

Weed control pre-sowing. 

Grazing management of spring 

pastures in the year prior to cropping. 

Seed dressings. 

Carefully timed spring spraying (e.g. 

TIMERITE®). 

Border spraying. 

Rotate chemical classes.

Understanding the lifecycle of pests can be important before deciding 

on control strategies 

Example 

Earth mites are active in the cool wet months from April to November. During the winter, they 

usually pass through three generations, with each lasting about 8-10 weeks depending on 

the species. During the hotter months of the year, earth mites avoid the hot dry conditions by 

producing over-summering eggs (diapause). 

For redlegged earth mites, the first two generations of mites lay predominantly winter eggs, 

usually on the under surface of the host plant leaf. In spring, mites stop laying eggs on plants 

and start producing the over-summering eggs, which are retained in the body (Figure 4.3). 

This knowledge can be used to time insecticide applications more strategically. Timerite ® is a 

strategy that works by controlling the number of redlegged earth mites emerging in autumn 

by minimising the number of diapause eggs produced (through a carefully timed spray in the 

previous spring) and therefore reducing the number of mites emerging from diapause. 

However, this approach is not as effective for other mite species. For blue oat mites and several 

other crop-emergence pests, a large number of diapause eggs are already present in paddocks 

by spring - well before the spring spray date recommended by Timerite ® . 

Summer 

eggs 

Diapausing eggs 

III 

Oct 

Nov 

Sep 

Dec 

Aug 

Jan 

Jul 

Feb 

II 

Winter eggs 

Jun 

Termination of diapause: 

summer conditions for 30-40 days 

Post-diapausing eggs 

Initiation of egg hatch: 

< 20 o C & >10 mm rain 

Figure 4.3 Typical lifecycle of redlegged earth mites in southern Australia 

Mar 

May 

Apr 

I 

Source: P. Umina (CESAR) 


75 


Acarina: Penthaleidae 

Blue oat mite (Penthaleus spp.) 


adult 

10 mm 20 30 

Globular-shaped, 

dark purplish blueblack 

body 

Eight red-orange 

legs (adults) 

Oval orange/red 

marking (anal 

shield) on back 



There are three recognised pest species of blue oat 

mites, but these are morphologically very similar and 

cannot be identified without the use of a microscope. 

Blue oat mites are similar in appearance to redlegged 

earth mites and may also be confused with other mite 

pests, such as Balaustium mites. The orange-red patch 

on the back of blue oat mites is unique and generally 

quite conspicuous when viewed with a hand lens. 

76 

Usually not found 

in foraging groups 


Nymphs are pink-orange in 

colour with six legs 


silvery-grey patches on leaves 

(similar to frost damage) 


Blue oat mites are widespread throughout the southern 

agricultural regions of Australia. They are broadly 

distributed across Victoria and New South Wales, the 

eastern half of Tasmania, the southern part of South 

Australia and the south-west of Western Australia. 

Blue oat mites often coexist with redlegged earth mites 

and both are typically active from autumn to late spring. 

Feeding damage can occur throughout this period but 

newly emerging crops and establishing pastures are 

most at risk.


A wide range of agriculturally important plants are 

attacked, but cereals, canola, lucerne and pastures 

are most susceptible. The three species differ in their 

host plant preferences which can sometimes assist 

identification. Broadleaf weeds, including cat’s ear and 

ox-tongue, are favoured by one species. 


Susceptible crops and pastures should be inspected 

regularly, particularly around the time of emergence. 

Mites may be present on the tops and undersides of 

leaves or on the ground. 


Blue oat mites penetrate the epidermal cells of plants 

and suck out cellular contents using their specialised 

mouthparts. This typically results in silvery-grey 

patches on plants which can sometimes be mistaken 

for frost damage. Feeding can also lead to distorted and 

shrivelled leaves, stunted growth and seedling mortality 

with a heavy infestation. 



French Anystis mite can suppress 

populations in some pastures. 

Crop rotations with non-preferred 

crops e.g. chickpeas. 

Cultivation. 

Weed management. 

Seed dressings. 

Border spraying. 

Carefully timed autumn sprays 

usually recommended. 


Spring spraying using Timerite® 

is largely ineffective against blue 

oat mites. 


77 


Acarina: Erythraeidae 

Balaustium mite (Balaustium medicagoense) 


adult 

‘Pad’-like 

structure 

on forelegs 

10 mm 20 30 

Body covered 

in short 

stout hairs 

Rounded body 

shape. Body colour 

variable but generally 

dark red-brown. 

Slow moving 

Damage 

symptoms: 

cupping and 

leathering 

of canola 

cotyledons 

Nymphs are smaller 

than adults and 

bright orange-red in 

colour with six legs in 

the larval stage 


bleached leaves leading to 

wilting and irregular white 

spotting to cereals 

and grasses 



Balaustium mites can be confused with other mite 

species. Adult Balaustium mites are approximately twice 

the size of adult redlegged earth mites and blue oat 

mites, and their body is larger and more rounded than 

Bryobia mites. 


Balaustium mites are broadly distributed across the 

southern coastal regions of Australia. They are found 

throughout most of Victoria, along the eastern side of 

New South Wales, in the south-east of South Australia and 

the south-west of Western Australia. Balaustium mites are 

typically active from March to November, although mites 

can persist on green feed during summer if available. 

Crops are most at risk during the seedling stage. Summer 

eggs hatch in autumn following significant rainfall. 



Unknown. 


78 


Control of summer weeds can prevent 

build up of mite populations. 

Avoid volunteer grasses within susceptible 

crops, such as cereals and pulses. 


Balaustium mites have a wide host range and are 

commonly found attacking canola, lupin and cereal 

crops. They will also feed on pasture legumes, lucerne, 

grasses and some broadleaf weeds. 


Balaustium mite feeding causes leaves to become 

bleached, which can lead to wilting and plant mortality 

under high infestations. Feeding results in the ‘cupping’ 

and ‘leathering’ of canola cotyledons and irregular white 

spotting on cereals and grasses. 


Monitor susceptible crops and pastures in autumn, 

particularly those with a history of chemical applications 

for redlegged earth mites. Established pastures can 

tolerate moderate numbers of Balaustium mites without 

sustaining significant damage but seedlings can be 

totally wiped out. Balaustium mites tend to be more 

active during the warmer parts of the day, so monitoring 

in the early afternoon is best. 

No chemicals currently registered. 

Balaustium mites have a high natural 

tolerance to many chemicals.

Acarina: Tetranychidae 

Bryobia mite or Clover mite (Bryobia spp.) 


adult 

10 mm 20 30 

Body flattened 

and dark grey-brown 

to fawn-orange in colour 

Scale-like hairs (setae) 

around edge of body 

visible under microscope 

Long front legs up 

to 1.5 times 

body length 

Eight pale 

orange legs in 

total (adults) 

Newly hatched mites are 

smaller and bright orange-red in colour 

with six legs in the larval stage and eight 

legs in the nymphal stage 

Distinct feeding 

trail damage 


There are over 100 species of Bryobia with at least six 

of these present in Australia. Bryobia mites may be 

confused with other mite species such as redlegged 

earth mites and blue oat mites. Their long forelegs are 

quite prominent and Bryobia mites are also lighter in 

colour, smaller and slower moving than other species. 


Unlike other broadacre mite species which are active 

from autumn to spring, Bryobia mites prefer the 

warmer months of the year. They are generally 

present from spring until autumn and are unlikely to be 

problematic in winter. Autumn-sown crops and pastures 

in paddocks containing summer or early autumn weeds 

are most at risk. 



Bryobia mites attack a variety of crops including canola, 

lupins, wheat, lucerne, vetch and clovers. 


Mites feed on the upper surface of leaves and cotyledons 

and leave distinctive trails of whitish-grey spots. When 

young leaves are affected they become discoloured and 

may fail to grow. On grasses, Bryobia mite feeding can 

resemble that of redlegged earth mites (leaf-silvering). 


Bryobia mites are active during the warmer parts of 

the day and may be difficult to detect during the early 

morning or in wet conditions. Look for mites and 

evidence of feeding damage in newly-sown crops and 

on clovers and Brassica weeds prior to sowing. 


Unknown. 


Control of summer and early autumn weeds 

can prevent build up of mite populations. 

Rotate crops with non-preferred plant types, 

e.g. chickpeas and oats. 

There is greater risk with rotations following 

pastures with high clover content. 

Some chemicals are registered for 

the control of Bryobia mites. 

Many insecticide rates used 

against other mite species 

may be ineffective (e.g. alphacypermethrin). 


79 


PREDATORY MITES Acarina: Snout mites (Bdellidae), 

Anystidae and Mesostigmata 

Various species - approximately 30,850 Australian species. 


BENEFICIAL 


Bdellidae adult 

10 mm 

20 

30 

Anystidae adult 

Mesostigmata adult 

Bdellidae Anystidae Mesostigmata 

Red bodied 


Lifecycle 


Many species of predatory mites have a lifecycle that 

coincides with pest earth mites - generally between April 

and December. Some species can be found throughout 

summer months in irrigated paddocks. They usually 

have many generations per year. 


Some predatory mites may be confused with pest earth 

mite species such as the redlegged earth mite and the 

Balaustium mite. Predatory mites are generally highly 

mobile (quick-moving) and have more prominent 

mouthparts than plant-feeding (phytophagous) pest 

species. 

80 

Very 

pointed 

snout 

* Well developed 

legs and fast 

moving 

* Usually 

brightly 

coloured 

Ute Guides, Southern (p. 135, 136)/ Western (p. 111, 112). 


Moves in a circular 

motion, hence the 

‘common name’ 

whirly gig mite 

* Large 

mouthparts 


* Fused body 

segments 

(cephalothorax 

and abdomen) 


Usually brown 

in colour 

Predatory mites are common throughout most of 

Australia and can be found in a variety of habitats. They 

are more likely to be found in under-grazed pasture 

paddocks where there is an abundance of plant cover 

and large prey populations. They are also found on 

weeds along roadside verges where mite prey are 

plentiful. 


There are a variety of native predatory species, as well 

as deliberately introduced species, that are important 

predators. These can reduce numbers of pest mites, 

lucerne flea and other springtails (Collembola). 

There is evidence that some predatory snout mites 

prevent damaging outbreaks of earth mites and lucerne 

flea in pastures and lucerne paddocks.

WASPS, BEES & ANTS (Order Hymenoptera) 

Hymenoptera - hymeno (membrane); ptera (wing) 

The Hymenoptera is divided into 71 families and contains 

about 15,000 species in Australia. The Hymenoptera is 

divided into two suborders - Symphyta (sawflies), which 

have no distinct waist and Apocrita (ants, bees and 

wasps), which have a distinct waist. This order includes 

harmful, as well as some of our most beneficial insects. 

Hymenopteran habits can vary considerably: some are 

predaceous; some parasitic; some cause plant galls; 

some feed on plant foliage and others, like honey bees, 

live on plant pollen and nectar. 

Wasps are important as parasitoids of broadacre pests 

and are the only group covered in this section. Bees are 

well known as important pollinators of crops and are 

frequently seen in flowering crops, such as canola during 

spring. Ants may also be abundant, particularly during 

the warmer months of the year, and may play a role 

as scavengers or in seed dispersal and burial. Sawflies 

include the ‘spitfire’ grubs which can occasionally be 

seen in clusters feeding on some native trees. 


Larval form 

Most are legless (maggot-like) and differ from similar 

looking fly maggots (Diptera) as they generally have 

visible chewing mouthparts and a developed head 

region. Larval forms of the parasitoid wasps are rarely seen 

in broadacre crops because they are generally concealed 

within the bodies of the prey from which they are feeding. 

Legs are present in some hymenopteran larvae, such as 

sawflies. Sawfly larvae look similar to moth caterpillars 

(Lepidoptera) because they have numerous abdominal 

prolegs, but they are more fleshy in appearance and do not 

have specialised hooks (crochets) at the base of prolegs. 

Adult form 

Can be winged or wingless insects. Winged species 

have two pairs of membranous wings with relatively few 

veins. The forewings are always slightly longer than the 

hind wings. The body of wasps, bees and ants are usually 

identified by their characteristic narrow waist or the 

constricted area that appears to separate the last two 

body segments (the thorax and the abdomen). Sawflies 

have wide waists. 

Mouthparts are formed for chewing (e.g. adult wasps) or 

can be modified for sucking (e.g. honey bees). In females, 

the abdomen ends in an egg laying tube (ovipositor) 

that is often prominent and can be modified to a stinger 

or a saw-like organ in some species. 

Lifecycle 


Lifecycles can vary considerably between species. Wasp 

parasitoids have a lifecycle that coincides with their host. 

In general, eggs are either injected into the host prey or 

attached to the outer body. The larval stage feeds on 

their host, which is often killed in the process. Larvae 

that feed internally either emerge from their host to 

pupate (e.g. braconid wasps), or emerge from the host 

as adults (e.g. aphid parasitoids). Different species can 

attack different stages of the host’s lifecycle. 

Many species are colonial and are fed by members of 

the colony. Adult wasps mostly feed on nectar and 

honeydew. 


cropping 

Predatory wasps (F: Ichneumonidae and Braconidae): 

Small to large wasps, including Diadegma semiclausum, a 

larval parasitoid of diamondback moth. Most beneficial 

wasps that attack moth larvae and aphids associated 

with broadacre crops belong to these two wasp families. 

Major species are covered in detail in this section on 

pages 84-88. 

Bees (F: Apidae): This family includes the introduced 

honey bee Apis mellifera, but also many native species 

that are important plant pollinators and may be seen 

visiting flowers. 

Ants (F: Formicidae): All ants belong to the one family. 

Worker ants, soldiers and males are commonly seen 

and in some species the queen is also visible. The 

feeding habits of adult ants can vary and may range 

from specialist to generalist predators, scavengers 

and omnivores, to seed-eaters, fungus or honeydew 

feeders. Some ant species play an important role in seed 

dispersal. 


81 


Hymenoptera: Cephidae 

Wheat stem sawfly (Cephus cinctus) and 

European wheat stem sawfly (Cephus pygmeus) 



larva 

pupa 

adult 

10 mm 20 30 

both species 

both species 

both species 

Wheat stem sawfly 

Strong head with 

strong mouthparts 

Thread-like 

(filiform) 

antennae 

Two sets of 

wings. Brown for 

wheat stem sawfly. 

Clear with brown veins for 

European wheat 

stem sawfly 


Sawflies are wasps and not flies. 

Larvae are legless (although European wheat stem 

sawfly has three pairs of reduced thoracic legs) with a 

head capsule and prominent mouthparts. They have 

a horn-like projection at the rear end of the abdomen 

(tubercule). Newly hatched larvae look transparent with 

tan-brown head regions. 

82 

Colouration can 

vary between the 

sexes and between 

populations 

Yellowish legs 


Narrow bodies, shiny 

black in colour with 

prominent bright 

yellow bands across 

the abdomen 

Sawflies undergo 2-3 moults and darken to a whitishyellow-green 

colour when mature. 

These species go through one generation per year and 

larvae overwinter in underground stems. Pupae are 

white and become darkened before adult emergence. 

Pupation occurs within a cocoon inside the stem near 

the roots or crown of the plant. Adults emerge in spring.


These closely-related species are difficult to tell apart 

and identification requires specialist knowledge. 

They can also be confused with other wasps. 







Wheat stem sawfly occurs in North America and the 

European wheat stem sawfly occurs in Europe, Asia, 

Africa and North America. 

Adults of both these species are weak flyers and 

transportation of larvae and pupae in straw is the most 

likely source of long-distance dispersal. 


Female wasps lay eggs in large, hollow-stemmed grasses 

such as wheat, rye, triticale, barley, oats and many other 

cultivated and wild grasses. 

Host plants are only susceptible to oviposition after 

stem elongation. 


Larval feeding reduces yield and quality. Larvae bore 

into stems and nodes, making a discoloured tunnel 

and leaving frass throughout. Mature larvae cut a notch 

around the inside circumference of lower stems. 

Damage varies depending on the year, locality, host 

plant and cultivar. The most obvious damage (caused by 

tunnelling and pupation) is weakening and clean cutting 

of stems and the subsequent lodging and loss of grain. 

Darkened spots can be visible on stems below nodes. 

This is a result of damage to the conducting tissue 

within the plant and the accumulation of impassable 

carbohydrates. 

Surveillance 

Damaged stems should be cut open to reveal 

eggs and larvae. Infested stems will contain 

saw-like frass inside. Any insect that resembles these 

wasps must be sent to a specialist for identification. 





















83 


WASP PARASITOIDS 

Hymenoptera: Ichneumonidae and Braconidae 

Various species - approximately 2000 species in Australia. 

Specialists (parasites and parasitoids) and transient 

BENEFICIAL 


Ichneumonidae 

adult 

10 mm 20 30 

though can vary from 2-120 mm 

*General body appearance: elongated 

and slender - long antennae (filiform) and 

legs highly variable in colour from orange 

to black, with or without markings 

Ichneumonidae wing venation to 

distinguish from braconids 


84 

Diadromus collaris 

Diadegma semiclausum 

Netelia producta 


*Waist constriction 

between thorax 

and abdomen 


*Long and thin 

exposed ovipositor 

(females) 

Light 

coloured legs 

Orange coloured 

body and legs 

*Wing venation can 

vary depending on genera 

(e.g. fused or no veins). 

Forewing 2mcu vein is 

always present 

*Wing venation 

full and many veins 

usually extend to 

the wing margin 

Diamondback moth cocoon (top) 

and cocoon of D. semiclausum 

inside diamondback moth cocoon 

(bottom), resulting in darkened 

cocoon with rounded ends

BENEFICIAL 


Braconidae 

adult 

10 mm 20 30 

though some can be up to 80 mm 

* Strong 

darkened cell 

* Wing venation 

incomplete and many 

veins usually terminate 

before the wing 

margin 

Braconidae wing venation to 

distinguish from ichneumonids 

Opivs sp. 

* 2mcu vein 

always absent 

* General body appearance: 

dark coloured (relatively uniform), 

long antennae (filiform), shiny body 

with paler coloured and long legs 

* Wing venation can 

vary depending on 

genera (e.g. fused or no 

veins) 

Aphidiinae 

Apanteles sp. (DBM parasitoid) 

Cotesia sp. (DBM parasitoid) 

Shiny black 

colour 

Dark coloured 

Aphid mummies - Aphidiinae wasp parasitoids 

Aphid skin 

casts 

Cocoons of Cotesia spp. 

are usually white/ 

yellow in colour 

Wasp exit 

hole 

Larva are internal in host 

bodies and legless 

(maggot like) 

Host pupae 

unparasitised 

(above) and 

parasitised (below) 

Distinct bloated appearance. 

Usually brown/buff/gold or 

bronze sheen colouring 

*indicates character for all species 


85 


Lifecycle 


Wasp parasitoids have a lifecycle that coincides with 

their host. The eggs are either injected into the host prey 

or attached to the outer body. Larvae feed internally on 

a host which is often killed in the process. They either 

emerge from the host to pupate (e.g. braconid wasps) or 

emerge from the host as adults (e.g. aphid parasitoids). 

Different wasp parasitoid species can attack at different 

stages of the host’s lifecycle. 


These wasps resemble small flies but they are usually 

shiny in colour and have two sets of developed wings. 

They can be confused with other wasp species, which 

are hard to distinguish in the paddock and identification 

often requires specialist knowledge. 

Evidence of parasitism 

in aphids: mummies 

Mummies are aphids that have been 

transformed into juvenile wasp casings and 

are only evident in the later stages of the 

wasp’s development. 

Look for: 

• round, bloated, buff to bronzed coloured 

aphids that are relatively slow moving or 

stationary; 

• emergence (exit hole) in mummies; 

• aphid skin casts - don’t confuse these 

with mummies or aphids. 


Common throughout most of Australia and can be found 

in a variety of habitats. Due to their close association 

with their host, their distribution is usually similar to that 

of their host. 



Ichneumonids and braconids attack a range of insects 

(mainly the larval form) where the developing wasp 

larvae can grow either inside the host (endoparasite) or 

externally on the outside of the host (ectoparasite). 

Ichneumonid wasps inject their eggs into native 

budworm or armyworm pupae within the soil. The 

feeding larvae prevents the moth from emerging, 

reducing future generations of pests. 

Braconids attack a range of caterpillar pests including 

armyworm, cutworm and budworm. They lay their 

eggs inside host caterpillars which are often < 10 mm 

in size. Developing wasp larvae feed internally, before 

burrowing through the skin of their host and spinning a 

silken cocoon externally. 

Many species are utilised as biological control agents 

of pest insects as they have a small host range - where 

a particular wasp attacks only one or several closely 

related genera. 

Some particular species include: 

Netelia producta attacks native budworms and other 

noctuid moths. 

Diadegma semiclausum and Diadromus collaris attack 

diamondback moth larvae. 

Ute Guides, Southern (pp. 123-125,127)/Western (pp.98,99,102,103). 

86 



in some caterpillars: 

external wasp cocoons 

Some wasp species will: 

• leave emergence (exit) holes in the 

caterpillar host and spin a cocoon nearby; 

• pupate inside the host, resulting in the 

host pupae differing in some way (e.g. 

changing colour or shape).

EGG PARASITOIDS 

Hymenoptera: Trichogrammatidae, Scelionidae and Mymaridae 


Specialists (egg parasitoids) and transient 


Trichogrammatidae 

adult 

10 mm 20 30 

* Robust marginal 

wing vein and no veins 

posterior to this 

* Tarsi three 

segmented (segments 

elongated and of 

roughly equal size) 

Scelionidae 

Telenomus spp. 

adult 

* Body fully 

hardened 

(sclerotised) 

10 mm 20 30 

* Antennae located low on ‘face’ 

with long 1 st antennal segment 

(scape) giving it a ‘z’- shape 

* Antennae short 

(4 - 9 segments) 

* Body not very 

hardened (sclerotised) 

although some are bigger 

* Wing venation 

completely reduced 

Parasitoid of 


* Very short 

ovipositor 

Trichogrammatidae 

parasitising Helicoverpa 

moth egg 

Wasp development in 

Rutherglen bug eggs 

*indicates character for all species 


87 


Lifecycle 

Trichogrammatidae, Scelionidae and Mymaridae are 

families of very small parasitic wasps that attack the 

eggs of insects and spiders. 

Wasp parasitoids have a lifecycle that coincides with 

their host. They lay their eggs inside the egg of a host 

(e.g. moth egg). The wasp larvae feed inside the host 

egg until maturity, when one or more new parasitic 

wasps emerge from the destroyed egg. 


They are confused with other wasp species and are 

hard to distinguish in the paddock. Identification often 

requires specialist knowledge. 

More often, they go unnoticed due to their small size 

(usually

Bees as pollinators 

Bees provide a valuable service to agriculture by 

improving pollination and increasing crop yields, as 

well as being an important primary industry in the 

production of honey. It is often necessary to apply 

insecticides to flowering crops to control pests; but it 

is important to consider the effects on bees and take 

steps to reduce the risk of bee poisoning. Bees taking 

chemicals back to a hive can result in mass bee deaths, 

devastation of entire hives and contamination of the 

honey. 

Bee poisoning can occur when: 

• Insecticides have been used on flowering crops 

and foraging bees are subsequently exposed to 

contaminated foliage, pollen or nectar. 

• Insecticides have been used on crops that are not 

flowering, but other plants in the target area are 

flowering, causing bees foraging on these plants to 

become contaminated. 

• Insecticides come in direct contact with bees that 

are present in or flying over the target area. 

• Bees access water that contains insecticide 

residues. 

• Spray drift causes direct contamination of bees, 

hives or flowering plants. 

Communication between crop owners and bee 

keepers is key to developing a mutually acceptable 

chemical program and minimising the risk to bees. 

Photograph courtesy: Susanne Richards 

Good practices for beekeepers 

• Before placing hives, advise all adjoining crop 

owners and any other persons or authorities likely 

to be applying insecticides. 

• Leave adequate signage in the area, including 

contact details. 

• Place hives in sheltered areas away from crops that 

are likely to be treated with insecticide. 

Bee-friendly practices for growers 

• Advise beekeepers with hives in the area that you 

intend to spray, giving as much notice as possible 

(at least 48 hours) to allow time to close down or 

move hives for the risk period. 

• Choose chemicals that are less toxic to bees – 

carefully read all product labels (particularly 

‘Protection of Livestock’ statements) to check 

toxicity to bees. 

• Avoid applying insecticides at times when bees 

are foraging. Consider spraying very early in the 

morning (low hazard/short residual chemicals 

only) or late in the evening after bees have stopped 

foraging. 

• Take care to avoid spray drift and contamination of 

water supplies. 


89 


LACEWINGS & ANTLIONS 

(Order Neuroptera) 

BENEFICIAL 

Green lacewings Chrysopidae - approximately 70 Australian species. 

Brown lacewings Hemerobiidae - approximately 50 Australian species. 



green lacewing larva 

brown lacewing larva 

green lacewing adult 

brown lacewing adult 

Adult 

Green lacewing 

10 mm 20 30 

*Large compound 

eyes (bulging) on side 

of head. Eyes have a 

metallic sheen 

Brown lacewing 

*Long beadlike 

(filiform) 

antennae 


90 

Larva 

Green lacewing 

Larvae carry 

dead prey material on 

their back 

*Elongated 

soft body 


*Two pairs of relatively equal sized, clear 

(membranous) wings. Numerous cross veins 

across entire wing surface (lace-like 

appearance). Wings held tent-like 

over body when at rest 

*Tapering body 

shape with 

highly mobile legs. 

Body covered in 

curved spines 

*Large sickleshaped 

mouthparts 

(modified jaws) 

projecting from the 

front of the head 

Brown lacewing 

* indicates character for all species

Lifecycle 


The females of many green lacewing species lay their 

eggs on the end of thin stalks. These may be attached 

to wood, leaves or other plant parts. Female brown 

lacewings lay eggs directly on vegetation. After hatching, 

larvae moult on average three times (sometimes four or 

five depending on the species) before they spin a silken 

cocoon in which they pupate. 

Development is usually rapid (approx. three weeks for 

brown lacewings at temperatures of 25-30°C), with 

numbers most prevalent in spring and autumn when 

large populations move to areas rich in prey. Many 

species of lacewings go through several generations a 

year. 


Lacewing adults can be distinguished from other 

winged insects by the presence of numerous veins 

and forked veins in wings. They can be confused with 

dragonflies (Odonata) and stoneflies (Plecoptera) 

but lacewings usually have longer antennae and 

softer bodies than dragonflies. Lacewings can also be 

confused with flying termites. Lacewings do not have 

two thin processes (cerci) at the end of the body 

(abdomen) as in stoneflies. 


Lacewings are common throughout most of Australia 

and can be found in almost all habitats. They are common 

on native vegetation, such as flowering eucalyptus, and 

in house gardens. Their numbers increase where there is 

an abundance of prey, such as aphids. 


Most larvae are active predators and have large sickleshaped 

sucking jaws, which they use to catch small 

insects and suck out their insides. 

Brown lacewing larvae and adults are both predatory, 

while only green lacewing larvae are predatory. Some 

adults of lacewing species supplement their diet with 

pollen and are omnivorous. 

Predatory lacewings prefer sap-sucking insects such 

as aphids, mites, scale insects and moth eggs, but as 

generalists they will eat a wide range of prey. 

Ute Guides, Southern (pp.137-138)/ Western (pp.113-114) 

Lacewing larvae are easily distinguished by the 

prominent jaws at the front of their head that take up 

almost all of the head region. Green lacewing larvae 

commonly cover themselves in debris and the bodies of 

their prey as camouflage. 


91 


SPIDERS (Order Araneae) 

BENEFICIAL 

Various families and species - approximately 2000 Australian species. 



Wolf spider (Lycosidae) 

Eight legs 

Various spider eye arrangements as 

seen from front (some of the eyes can be 

found on top of the head). 

Most spiders have eight eyes 


Abdomen 

Spinnerets 

Lifecycle 


Most spiders have one generation per year. 

Spiders are easily recognisable but identification of specific 

families and species requires specialist knowledge. 

All spiders are predatory and use a variety of hunting 

strategies to capture their prey, therefore it is easier to 

classify them in their functional group (e.g. web-builders 

or active hunters). 


Spiders can range from just 0.5 mm in size to large 

species such as the huntsman with a leg span of over 20 

cm. All spiders spin silk from a group of spinnerets at the 

end of the abdomen, but not all are web building for the 

purpose of catching prey. 

92 

Fused head 

and thorax 

(cephalothorax) 

Mouthpart (palps). 

Swollen on the ends 

(males) 


Mouthpart (chelicerae) used for 

grasping and killing, usually pointed 

downwards. Fangs can be pointed sideways 

and inwards or pointed backwards 

towards the centre of the body 

Source: Line drawings modified from Child (1965) 


There are at least six groups of spiders that commonly 

occur in field crops, with the most common being active 

hunters (rather than web-building). These include the 

wolf and huntsman spiders that chase down their prey, 

and trapdoor spiders that lie in wait to grab prey walking 

past their burrows. Smaller spiders, such as jumping 

spiders, are usually well-hidden ambush specialists and, 

although harder to see, are just as important. 


Spiders consume a wide range of prey. They are effective 

predators not only of pests but also on other predators. 

Ute Guides, Southern (pp. 134)/Western (pp. 108-110).

More Information 

Website links 

DAFWA 

Department of Agriculture and Food, 

Western Australia 

www.agric.wa.gov.au 

PestFax/PestFacts services 

The PestFax/PestFacts services are free 

interactive tools designed to keep growers and 

advisers informed about pest-related issues 

- and solutions - as they emerge during the 

growing season. 

SARDI 

CESAR 

PIRSA 

Vic DPI 

DEEDI 

I & I NSW 

CSIRO 

GRDC 

PHA 

PaDIL 

South Australian Research and 

Development Institute 

www.sardi.sa.gov.au 

CESAR 

www.cesaraustralia.com 

Department of Primary Industries and 

Regions, South Australia 

www.pir.sa.gov.au 

Department of Primary Industries, Victoria 

http://new.dpi.vic.gov.au/agriculture 

Department of Employment, Economic 

Development and Innovation, 

Queensland 

www.dpi.qld.gov.au/26_3510.htm 

Industry and Investment, New South Wales 

www.dpi.nsw.gov.au 

Commonwealth Scientific and Industrial 

Research Organisation 

www.csiro.au 

Grains Research and Development 

Corporation 

www.grdc.com.au 

Plant Health Australia: Grains Biosecurity 

www.planthealthaustralia.com.au/go/ 

biosecurity/grains 

Pest and Disease Image Library 

www.padil.gov.au 

The services are distributed as electronic 

newsletters and aim to help growers achieve 

maximum yield and quality for the lowest 

cost by providing timely information about 

pest outbreaks, effective controls and current 

information about relevant and new research 

findings. 

To provide this service PestFax/PestFacts draws 

on the field observations of consultants, growers 

and researchers across southern Australia 

as they report on the location and extent of 

invertebrate outbreaks. 

The PestFax/PestFacts services, part of GRDC’s 

National Invertebrate Pest Initiative (NIPI), also 

issue warnings (or reminders) for a range of 

invertebrate pests of broadacre crops, including 

pulses, oilseeds, cereals and fodder crops. 

For further information or to subscribe to these 

services visit: 

PestFax (DAFWA) 

http://www.agric.wa.gov.au/pestfax 

PestFacts SA & western Victoria Edition (SARDI) 

www.sardi.gov.au/pestfacts 

PestFacts South-Eastern (CESAR) 

http://cesaraustralia.com/sustainableagriculture/pestfacts-south-eastern/ 


93 


IPM Principles 

and Case Studies 

5 

IPM

SECTION 5 

IPM Principles and Case Studies 

Introduction ....................................................... 2 

Biological control .................................................. 4 

Biological agents .......................................................5 

Conservation and enhancing natural enemy numbers ...................7 

The impact of biological agents on pest populations ....................7 

Cultural, physical and other control of insects ....................... 10 

Host plant availability . ................................................ 10 

Removing the ‘green bridge’ .......................................... 10 

Host plant susceptibility and resistance ................................11 

Stubble retention, minimum tillage and changing farming systems .....11 

Grazing ...............................................................11 

Chemical control of insects and resistance issues .................... 12 

Pesticide usage and IPM ...............................................12 

Selective insecticides ..................................................13 

Insecticide resistance and tolerance ....................................13 

Conserving the benefits of insecticides using an IPM approach . .........15 

Rotation of insecticide groups .........................................15 

Area-wide management (AWM) .................................... 16 

What is AWM ........................................................ 16 

The benefits of AWM ................................................. 16 

For which broadacre pests is AWM applicable ........................ 16 

First steps towards AWM .............................................. 16 

AWM examples ........................................................17 

Case studies ....................................................... 20 

Case study 1: 

Shelterbelts in agricultural landscapes suppress invertebrate pests . .... 20 

Case study 2: 

Selective chemicals and their role in broadacre cropping .............. 21 

Case study 3: 

Creating pest problems and losing money with broad-spectrum pesticides 22 

Case study 4: 

Seed dressings protect emerging canola seedlings from pest attack . ... 23 

Case study 5: 

The effects of grazing on redlegged earth mite populations ........... 24 

Figures and Tables 

Figure 5.1 Flow chart for IPM decision making ............................3 

Figure 5.2 Schematic moth lifecycle and associated parasitoid (wasp) . ......6 

Figure 5.3 Diagram illustrating the concept of AWM ........................18 

Figure 5.4 How IPM and AWM work together to achieve pest 

management at larger scales ................................ 18 

Table 5.1 Beneficial species commonly observed in broadacre crops . . . . . . . . 8 

Table 5.2 Impact of insecticides on natural enemies in crops ..............14 

Table 5.3 Pest species for which an AWM approach may prove more useful 

than a paddock-by-paddock approach .........................19 

SECTION 5 IPM Principles and Case Studies 

1 


Introduction 

In its simplest form, integrated pest management (IPM) 

is a control strategy in which a variety of biological, 

chemical and cultural control practices are combined to 

manage and prevent pests (invertebrates) from reaching 

damaging levels in crops. The integration of a range of 

effective, economic and sustainable pest management 

tactics to deal with pests replaces the reliance on any 

single control method to give stable long-term pest 

control. 

The sole reliance on chemical control for pest 

management is NOT a sustainable long-term 

solution. IPM does not mean the abandonment 

of pesticides but aims to reduce the frequency 

of pesticide applications. 

Pesticides within an IPM framework are tools used 

to assist in pest control when biological and 

cultural control methods are insufficient. 


IPM principles involve a sound understanding of 

pest biology, natural enemies of pests and host crop 

phenology to allow rational use of a variety of control 

tactics. These control strategies generally fall into the 

categories listed below. 

Biological control 

• The conservation or release of natural enemies 

(predators, parasites and pathogens) that feed on or 

attack pests (e.g. control of canola aphids by ladybird 

and lacewing predators). 

Cultural control 

• Tactics such as crop rotation, trap cropping, crop 

hygiene, removal and destruction of weeds (e.g. 

‘green bridge’) and diseased plants, planting/ 

harvest date selection, site selection, cultivar 

and variety selection and nutrient management. 

The incorporation of nectar-producing plants to 

encourage natural enemies. 

Mechanical/physical control 

• The use of barriers such as windbreaks and physical 

disturbances of the system (e.g. mowing, grazing, 

ploughing and inter-row cultivation). 

Genetic 

• The use of crop varieties bred or genetically 

developed for pest resistance/tolerance. 

Pesticides 

• Strategic chemical applications that are justified by 

monitoring and use of valid pest threshold levels. 

• Where applicable, the use of selective chemical 

options that are specific to target pests and relatively 

harmless to natural enemies (e.g. pirimicarb for 

aphids, Bt for caterpillars and pesticide baits for 

beetle pests) should be used in preference to broadspectrum 

insecticides. 

• Spray application techniques (e.g. correct timing, 

nozzle selection and coverage). 

2 


IPM advantages 

• Natural enemies are encouraged to help maintain 

pests. 

• Maintaining chemical effectiveness by reducing (or 

delaying) the risk of pests developing resistance to 

insecticides. 

• Reduced chemical contamination of produce and 

environmental damage. 

• Reduced use and dependence on chemicals. 

• Increased health benefits to producers, their families, 

staff and consumers by decreased pesticide usage. 

• Development of more robust cropping systems that 

do not rely solely on one method of control. 

• Potential to save money and time spent applying 

pesticides. 

IPM disadvantages 

• More complex than using chemical control alone. 

• Requires a time commitment for regular crop 

monitoring. 

• Requires an understanding of the ecology of the 

cropping system, the ecology of the pests, their 

natural enemies and the surrounding environment. 

• Lack of economic threshold information on many 

pests and the control their natural enemies provide, 

can lead to uncertainty of acceptable damage levels 

or risk to crops associated with IPM strategies. 

• Potential crop damage associated with the transition 

to an IPM system.

The IPM decision-making process 

IPM principles are well documented, but when and how 

to intervene remain the key questions for most growers 

and advisers. To successfully implement good decisionmaking 

practices in an IPM framework one must gain 

confidence in, and adopt, a new set of tools for the 

decision-making process. This involves a whole-systems 

approach that extends beyond simply killing pests when 

they appear. 

A sound understanding of the following is required: 

• pest and beneficial identification skills; 

• pest and beneficial lifecycles, biology and ecology; 

• effective crop monitoring or scouting skills that 

provide specific information on pest and beneficial 

activity; 

• effects of pest damage on crop yield and quality 

utilising economic thresholds as the front line for 

pest control decisions; 

• the impact of different control tactics on pest 

populations and their natural enemies. 

A change in mindset on how to tackle pests, 

coupled with the development of a new set of 

decision-making tools is critical for sustainable 

pest management. 

One of the most difficult parts of any IPM program is 

deciding when and what action to take. 

Flow charts with set pathways, like the one below (Figure 

5.1), provide a good start to help you develop a decisionmaking 

process and a flexible program that can be 

modified to suit any crop-production system. It is 

important to accept that longer time-frames may be 

required to achieve pest control through the adoption 

of IPM methods (i.e. actions may need to be put in place 

a year or two prior to receiving the benefit). 

Figure 5.1 Flow chart for IPM decision making 

1. Identify the pests that are present. Previous monitoring and paddock history will help 

inform this decision (consider both the primary pest and other pests). 

CONTINUE MONITORING 

SPRAY SELECTIVE 

INSECTICIDE 

USE BAIT, SEED DRESSING, 

BORDER SPRAY OR OTHER 

FARM PRACTICES 

USE A NON-SELECTIVE 

INSECTICIDE 

(important to assess subsequent 

damage to beneficial species) 

YES 

NO 

YES 

YES 

2. Are there sufficient beneficial species that could 

control the pest in the short-term or long-term 

3. Are there sufficient pests to cause an economic 

loss or crop damage This a judgement that each 

individual will have to make. 

4. Are there selective (chemicals that target only the 

pest), cost effective insecticides available to spray 

5. Are there baits, seed dressings, border sprays 

or other farm practices that could be used 

Forward planning is essential to maximise the pest control options available. If control of the pest 

problem is only addressed in the year of sowing, the options and ability to minimise the effect on 

beneficial species through different treatment options is greatly reduced. For example, if a seed 

dressing is not used, then pest control options are further reduced to just in-crop spraying. 

YES 

NO 

NO 

NO 


Source: Modified from Cam Nicholson IPM brochure Grain and Graze Project. 

3 


Biological Control 


All pest populations are regulated to some degree by 

the direct effect of other living organisms. Beneficial 

species (natural enemies) play a vital but often unseen 

natural biological control role in cropping systems. The 

concept of integrated pest management (IPM) is based 

on naturally-occurring levels of biological control agents 

or a deliberate effort to increase these levels. 

Biocontrol agents may be arthropods (insects, 

mites, spiders) and disease-causing microorganisms 

and pathogens (bacteria, fungi, protozoa, 

nematodes and viruses). 

Many invertebrate natural enemies are highly mobile 

and will move from crop to crop if left unsprayed. They 

can help keep pest populations under control but the 

degree to which they can be used will vary with crop 

type, area and time of year. Broad-spectrum insecticides 

generally have harmful effects on beneficial invertebrate 

populations. 

Major characteristics of beneficial organisms 

and pathogens: 

• They kill, reduce reproduction, slow growth, or 

shorten the life of pests. 

• Often host specific i.e. will attack only target pest 

species or are specific to a life stage. 

• Their effectiveness may depend on environmental 

conditions or host abundance. 

• The degree of control may be unpredictable. 

• They are relatively slow acting and may take several 

days or longer to provide adequate control. 

Biological control is more easily implemented in intensive 

forms of agriculture (such as tree crops or horticulture) 

where the maintenance of biological control agents and 

the expenditure of resources to monitor and maintain 

high levels of biological control are economically 

justified. 

In extensive and discontinuous broadacre agricultural 

systems it is more difficult to utilise biological control, 

but natural agents are often seasonally abundant and 

can reduce pest damage in crops and pastures. Pest 

attack would be more frequent and severe without them 

in our systems. While it may not be viable to employ all 

biological approaches and all components of IPM, we 

can improve the management of beneficial organisms 

that naturally occur. 

4 


There are several different approaches to using biological 

control agents, including: 

Classical biological control 

This involves the deliberate introduction and 

establishment of imported (exotic) natural enemies to 

control established pests. In Australia, there have been 

many parasitoids (e.g. aphid wasp parasitoid Aphidius 

ervi) and predators (e.g. predatory mite of lucerne 

flea, Bdellodes lapidaria) imported and established in 

broadacre agriculture. There are also a number of weed 

biocontrol agents that have been released (e.g. the 

flea beetle, Longitarsus echii for Paterson’s curse weed 

control). 

This control approach must adhere to the Biological 

Control Act (1987) and takes years before biocontrol 

agents can be released. 

Inundation or seeding biocontrol agents 

Commercially available biocontrol organisms can be 

either mass-released (inundative) to have an immediate 

impact or released early (seeded) into the system so they 

can breed up with the pest. These approaches are more 

suited to intensive forms of agriculture, high value crops, 

small areas and those with market requirements for low 

or no pesticide use. 

Natural biocontrol 

Naturally occurring beneficial populations do their 

own thing, provided they are not sprayed with broadspectrum 

insecticides. The preservation of natural 

enemies already in the system is the most effective 

approach likely to be used in broadacre systems. 

Therefore, various strategies (e.g. cultural techniques) 

that preserve and enhance natural enemies should be 

favoured, such as providing alternate food sources (e.g. 

nectar sources, non-pest hosts) and refuge habitats (e.g. 

remnant vegetation).

Biological agents 

GENERALIST predators 

Predators (adults and immature forms) are mainly freeliving 

species that consume a large number and range 

of prey during their lifetime and are therefore often 

regarded as generalists rather than specialists. 

Characteristics of generalist predators 

• Generally larger in size than their prey. 

• Consume many prey (often attack immature and 

adult prey). 

• Males, females, immatures and adults all may be 

predatory. 

• Can be transient (e.g. ladybirds) or residential (e.g. 

predatory mites). 

• Have different approaches to how they find and kill 

their prey (e.g. mantids sit and wait and may also be 

camouflaged while ladybird beetles actively search 

for prey). 

• Modification of their body parts in keeping with their 

predatory style (e.g. well developed mouthparts and 

legs, streamlined bodies or other modified structures 

to enhance prey capture). 

Main predator groups: spiders (Arachnida), predatory 

mites (Acarina), lacewings/antlions (Neuroptera), beetles 

(Carabidae, Coccinellidae, Staphylinidae), hoverflies 

(Syrphidae) and true bugs (Hemiptera). 

SPECIALIST parasites and parasitoids 

Parasite - an organism that lives in or on the body of 

another organism (the host) during some portion of its 

lifecycle (e.g. parasitic mites). They mostly do not kill the 

host. 

Parasitoid - invertebrate that oviposits externally on, or 

internally in a host, where eggs hatch and larvae feed 

and develop into adults, eventually killing the host 

(e.g. some flies and wasps). See Figure 5.2 for a schematic 

diagram of a parasitoid and its host. 

Characteristics of parasitoids and parasites 

• They are highly specialised and host specific, often 

with a prolonged and specialised relationship with 

one or a few hosts (i.e. will attack only one species or 

a particular genus). 

• They tend to be smaller than their host. 

• Only the female searches for the host to deposit eggs. 

• They are often very susceptible to chemicals, 

particularly the adults. 

• Can be gregarious or solitary. 

In broadacre agriculture, most biological control agents 

in this category are parasitoids. 

Main parasitic and parasitoids groups: wasps (e.g. 

Braconidae, Ichnuemonidae, Trichogrammatidae, 

Scelionidae, Mymaridae, and Chalcidoidea), and flies (e.g. 

Tachinidae, Calliphoridae and Sarcophagidae). 

It is important to know what parasitoids look like, 

and which pests and life-stages they attack. 


Ways to determine if parasites or parasitoids are present: 

• look for evidence of an ‘exit hole’ in the host caused by 

the parasitoid (e.g. aphid parasitoid or ‘mummified’ 

aphid bodies); 

• dissect samples (can be difficult if an insect is very 

small); 

• rear individuals of the pest in an insect proof jar to 

see if any parasitoids emerge; 

• observe deformed caterpillars or wasp cocoons 

surrounding caterpillars. 

RESIDENTIAL or TRANSIENT modes 

Residential: Permanently living within the 

system and most relevant at crop establishment. 

Usually have limited dispersal capabilities. 

Pests include mites, cockchafers, wireworms and 

slugs. 

Beneficials include predatory mites, carabid 

beetles and native earwigs. 

Transient: Mobile species that do not 

permanently reside in a system and generally 

have shorter generation times compared with 

residential species. Beneficial species will often 

follow the movements patterns of prey in and 

out of crops. 

Pests include aphids and moths. 

Beneficials include ladybirds, lacewings, and 

parasitic wasps. 


5 


Figure 5.2 Schematic moth lifecycle and associated parasitoid (wasp) 

Un-parasitised 

Moth 

Eggs 

Moth pupae 

Caterpillar 

Parasitised 

Lifecycle broken here by larvae 

and pupae parasitoids 

Parasitic wasp 

emerges 

Moth 

Parasitic wasp 

cocoon develops 

Eggs 

Lifecycle broken 

here by egg 

parasitoids 

Parasitic wasp laying 

an egg in a caterpillar 

Source: C. Paull (SARDI) 


Disease-causing micro-organisms 

and pathogens 

Fungi: Fungi are the most common diseases of insects. 

Fungal spores that come in contact with insects 

germinate under certain conditions and fungal hyphae 

penetrate the insect’s skin (cuticle), often releasing 

toxins. The fungus grows inside the insect body and 

leads to its eventual death. Useful genera: Beauveria, 

Entomophthora, Hirsutella, Metarhizium, Nomuraea and 

Verticillium. 

The disadvantages of fungi include: 

• sporulation and germination require ideal conditions 

(adequate moisture and humidity) to affect control in 

the field of large pest populations; 

• difficult to mass produce consistently for 

commercial use and have a limited storage life. 

Metarhizium is available for locust control (e.g. Green 

Guard TM ). 

Viruses: Many viruses infect and kill insects. This occurs 

mainly via viral proteins damaging the insect’s gut lining. 

Several useful naturally-occurring viral groups include: 

the nuclear polyhedrosis viruses (NPVs), granulose 

viruses (GVs), cytoplasmic polyhedrosis viruses 

(CPVs), and entomopoxviruses (EPVs). NPV is available 

commercially (e.g. Gemstar TM ). 

6 


Bacteria: Bacteria rarely kill insects but one species, 

Bacillus thuringiensis (Bt), and variants of the strain have 

been widely used as a biocontrol agent. 

Bt is mainly used against caterpillar pests (Lepidoptera) 

but is also active against some beetles (Coleoptera) and 

mosquito larvae (Diptera). It is formulated as a dust or 

as granules and then applied as an aqueous spray. 

The bacteria need to be applied when pest larvae are 

young as there is a delayed killing action. Bt toxins are 

also produced in some genetically modified crops such 

as cotton and corn. Check out the Bt checklist on page 

13 in this section. 

Nematodes: Nematodes are microscopic invertebrates 

with a smooth, cylindrical body and no legs. They 

actively search for their host, then enter the body 

through natural openings where they release bacteria 

that digest the insect. The nematodes then feed on 

the bacteria/insect slurry. Eventually the dead insect 

bodies rupture and release further nematodes. Some 

nematodes are commercially produced as a dehydrated 

cellulose mixture, which is rehydrated before use in high 

value crops.

Conservation and enhancing natural 

enemy numbers 

An effective strategy in broadacre systems is the 

conservation and enhancement of beneficial species 

that occur in paddocks naturally. The abundance of 

beneficial species is affected by host pests, sugar 

sources, mating partners, overwintering sites, shelter, 

climatic conditions and insecticide usage. Preserving or 

enhancing these requirements will ultimately lead to an 

increase in their overall effectiveness. 

Practical techniques that could help 

to conserve and enhance beneficial 

effectiveness include: 

• tolerating some pest damage early in the season; 

• delaying spraying if large numbers of beneficials 

are present and pest damage is below economic 

threshold levels; 

• leaving some areas unsprayed if these areas are 

harbouring beneficial species; 

• using selective insecticides (where available) that are 

less harmful to beneficial species (e.g. pirimicarb for 

aphid control); 

• using appropriate timing and application of 

pesticides (i.e. using registered rates when economic 

pest damage is about to occur and not as ‘insurance’ 

sprays); 

• spraying late evening to minimise direct exposure of 

foraging bees; 

• using beneficial insect attractants (e.g. food sprays) 

in high value crops; 

• using refuge areas (e.g. shelterbelts with shrubs/ 

trees) or nursery crops which help to conserve 

sources of natural enemies; 

• maintaining habitat diversity on farm by using a 

mixture of crops and preserving bushland; 

• using insect resistant crop varieties. 

There is a growing awareness of the utilisation of 

‘ecosystem services’ for long-term sustainability 

of some agricultural systems and the ability of these 

services to generate economic and ecological benefits. 

Extensive research overseas has demonstrated the value 

of manipulating landscape features to assist in pest 

control (see cultural control in this section). 

The impact of biocontrol agents on pest 

populations 

Determining the effectiveness of biocontrol agents can 

be difficult and is often underestimated, as their actions 

are not as immediate as those seen with insecticide use. 

It is also very difficult to assess and quantify the amount 

of prey taken, since biological agents tend to destroy 

their hosts leaving little evidence of their actions. 

Under changing environmental conditions and crop 

management practices, pest and beneficial organisms 

are rarely stable but oscillate to different degrees. The 

response time of biological control agents is often too 

long for the control of pest populations approaching 

economic levels and those increasing quickly in numbers 

(e.g. a migratory moth flight with a large egg-lay event 

in a paddock). 

Look for trends in monitoring data 

Monitoring numbers of pest and beneficial species 

over time by sampling crops can provide an estimate 

of the impact that natural enemies may be having. 

For example, large numbers of ladybirds, lacewings 

or hoverfly larvae picked up in sweep net sampling of 

canola crops indicates that these beneficials are feeding 

on pests, within the crop. 

Research in broadacre grain crops will hopefully develop 

and utilise beneficial / pest ratios similar to those used in 

the cotton industry. 

Food webs 

Pests and natural enemies are part of a complex 

food web of potentially many hundreds of 

species. Individuals interact with others in a 

variety of ways and can use resources from many 

habitats across the landscape (see case study on 

shelterbelts in this section on page 17). 

For example, adult lacewings use flowering 

plants as a source of nectar and pollen and may 

also eat honeydew exuded from other insects. 

Easy access to these resources improves an adult 

lacewing’s lifespan and their ability to produce 

eggs. Spiders can consume a wide variety of nonpest 

and predatory species and these can be 

valuable food resources prior to pest populations 

developing in fields. 

Field crops, despite being widespread across a 

landscape, are extremely temporary habitats so it 

is important that natural enemies can find all the 

resources they need from other habitats across the 

landscape, such as perennial vegetation patches. 


7 


Table 5.1 Beneficial species commonly observed in broadacre crops 

Name 

Beneficial 

Life 

stage 

Mode of 

mobility 

Name 

Prey or host 

Life stage 

Monitoring 

method 

Field 

prevalence 

Carabid beetles 

O: Coleoptera 

F: Carabidae 


Larvae 

and 

adults 

Resident 

Ground-dwelling pests. 

Slugs, caterpillars, 

European earwigs, 

true wireworms, false 

wireworms and moth 

larvae 

Larvae, 

nymphs and 

adults 

Shelter traps 

or night 

observation 

All year in 

either adult or 

larval forms 

Predatory mites 

O: Acarina 

F: Various families 

and species 

e.g. snout mites 

Bdellodes species 

Nymphs 

and 

adults 

Resident 

Redlegged earth mite, 

blue oat mite and 

lucerne flea 

Nymphs 

and adults 

Direct 

search, 

suction 

samples and 

pitfalls 

Autumn to 

spring 

Native earwigs 

O: Dermaptera 

F: Labiduridae 

e.g. Labidura truncata 

and some other 

native species 

Nymphs 

and 

adults 

Resident, 

some 

capable 

of flight 

Caterpillars, mites, 

lucerne flea and some 

pest earwigs 

Larvae, 

nymphs 

and adults 

Direct 

search 

under 

wood, rocks, 

etc., shelter 

traps 

All year 


Spiders 

O: Araneae 

F: Various families 

and species 

Hover flies 

O: Diptera 

F: Syrphidae 

Brown lacewings 

O: Neuroptera 

F: Hemerobiidae 

Green lacewings 

O: Neuroptera 

F: Chrysopidae 

Predatory bugs 

Nabids, damsel bug 

O: Hemiptera 

F: Nabidae 

Shield bugs 

O: Hemiptera 

F: Pentatomidae 


Assassin bugs 

F: Reduviidae 


8 

Nymphs 

and 

adults 

Larvae 

only 

Larvae 

and 

adults 

Larvae 

only 

Nymphs 

and 

adults 

Nymphs 

and 

adults 

Nymphs 

and 

adults 

Resident, 

some are 

carried by 

winds as 

juveniles 

Transient 

Transient 

Transient 

Transient 

Transient 

Transient 


Flies, crickets, lucerne 

flea, aphids, caterpillars 

and moths 

Most invertebrates 

including other predators 

A range of soft-bodied 

insects, but prefer 

aphids 

Various moth pests 

Aphids, thrips and mites 


Aphids, thrips and mites 


Aphids, leafhoppers, 

mirids and mites 


Various moth pests, 

other bugs and wasps 

Larvae, 

nymphs 

and adults 

Nymphs 

and adults 

Larvae 

and eggs 

Nymphs 

and adults 

Larvae 

and eggs 

Nymphs 

and adults 

Larvae 

and eggs 

Nymphs 

and adults 

Larvae 

and eggs 

Larvae, 

nymphs and 

adults 

Direct 

search, 

suction 

samples and 

pitfalls 

Direct 

search and 

sweep net 

Direct 

search and 

sweep net 

Direct 

search and 

sweep net 

Direct 

search and 

sweep net 

Direct 

search and 

sweep net 

Direct 

search and 

sweep net 

All year for 

most species 

Predominantly 

spring to 

autumn 

Predominantly 

spring to 

autumn 

Predominantly 

spring to 

autumn 

Predominantly 

in spring 

Predominantly 

in spring 

Predominantly 

in spring

Table 5.1 Beneficial species commonly observed in broadacre crops (continued) 

Name 

Beneficial 

Life 

stage 

Mode of 

mobility 

Name 

Prey or host 

Life stage 

Monitoring 

method 

Field 

prevalence 

Ladybird beetles 

O: Coleoptera 

F: Coccinellidae 


Larvae 

and 

adults 

Transient 

Various moth pests, 

aphids, leafhoppers, 

thrips and mites 

Eggs, larvae, 

nymphs and 

adults 

Direct 

search and 

sweep net 

Predominantly 

in spring 

Parasitic wasps 

Wasp parasitoids 

(medium-large, 

10-20 mm) 

F: Ichneumonidae 

Diadromis spp. and 

Diadegma semiclausim 

Adult 

Transient 


Larvae 

Direct 

search and 

sweep net 

Predominantly 

in spring 

Netelia spp. 

Heteropelma and 

Lissopimpla spp. 

Adult 

Transient 

Armyworms, cutworms 

and native budworms 

Larvae 

Direct 

search and 

sweep net 

Predominantly 

in spring 

Ichneumon sp. 

Adult 

Transient 

Native budworm and 

some armyworms 

Larvae 

Direct 

search and 

sweep net 

Predominantly 

in spring 

Wasp parasitoids 

(small


Cultural, physical and 

other control of insects 

Cultural farming management practices and the use of 

mechanical or physical techniques are incorporated into 

an IPM framework. These management practices can 

minimise pest attack by altering the habitat to achieve 

partial or complete pest control. 

Cultural practices and techniques for pest control 

have been used in agriculture for centuries and their 

effectiveness is frequently underestimated or not fully 

utilised. Examples include plant varietal selection, time of 

sowing, crop rotation, crop hygiene and cultivation/fallow. 

Other practices or tactics aim to alter paddock habitat to 

promote beneficial species and encourage their survival. 

These areas are relatively new in broadacre and need to 

be further researched and developed. 

Host plant availability 

Most insects have preferred hosts (oligophagous) and 

some are host specific (monophagous). By manipulating 

plant host availability, pest populations can be suppressed 

or controlled. Seasonal variations will naturally provide a 

wide range of host availability options for insects. 

Destroying host plants using chemical fallowing or a 

cultivation fallow for several weeks prior to crops being 

sown will greatly reduce the populations of many pests 

by depriving them of a food source. Complete fallow 

periods (no green material) of about two weeks are 

sufficient to starve-out many pests. 

Changing farming practices in some cropping areas has 

seen the introduction of lucerne, millet, grain, sorghum 

and other summer host plants into the farming system. 

These plants will increase the feed availability and 

survival of some insect pests. Examples include aphids, 

Helicoverpa spp., Sitona weevil, Rutherglen bugs and 

African black beetle. 

Managing host weeds for some pests is also important. 

For example, the vegetable weevil, prefers to feed on 

capeweed. They can often be found in high densities 

in pastures or areas of paddocks where capeweed is 

dominant. Use of selective herbicides and grazing to 

manage capeweed in pastures prior to sowing canola 

will help to reduce weevil numbers below damaging 

levels. 

Sampling pre-season weeds for the presence of insects 

will provide an indication of potential pest pressure 

that may affect crop seedlings at germination. 

10 


Removing the ‘green bridge’ 

The term ‘green bridge’ describes the role of weeds and 

crop volunteers in helping pests cross from one cropping 

season into the next. Late summer and early autumn 

rainfall is an important trigger for the establishment 

of the ‘green bridge’ in parts of Australia where winter 

cropping dominates. Availability of summer/early 

autumn weeds within regions can provide pests with a 

food source that enables them to develop and increase. 

Pest populations can then infest any subsequent crops 

sown early in the season, when pests transfer from dying 

weeds (e.g. following herbicide sprays) to new seedlings. 

The most damaging situations usually occur where pest 

populations have had several weeks or even months to 

increase in number prior to crops being sown. These 

seasonal situations are usually accompanied by high 

temperatures that provide fast developmental rates for 

pests. 

While individual farmers will benefit from efforts to 

eradicate the ‘green bridge’ on their properties, effective 

control requires neighbours to work together to remove 

volunteers and weeds simultaneously. Weeds should be 

controlled early. Plants along fencelines, around sheds 

and roadsides should all be targeted as potential hosts 

for pests. Seasonal conditions provide an indication of 

the ‘green bridge’ risk from year to year. 

Examples of pests that can use ‘green bridges’ are 

lucerne flea and Bryobia mites. These species will have 

an early hatch from their over-summering diapause state 

and increase rapidly if good rainfall provides abundant 

weed growth. Snails and slugs will also emerge from 

their summer resting phase to commence development 

when green hosts are abundant. Aphids and Rutherglen 

bugs are solely reliant on the availability of host plants 

to over-summer (i.e. survive between seasons). The 

abundance of these plants available during summer/ 

early autumn will determine the level of their carryover 

between seasons. Seasons with dry summer/early 

autumn periods often result in lower pest pressures. 

Reduced pest pressure can also occur in seasons where 

‘false breaks’ enable insect activity on weeds following 

early rainfall, before prolonged hot dry weather destroys 

those weeds. 

The risk of viral diseases such as barley yellow dwarf 

virus (BYDV) or wheat streak mosaic virus (WSMV) is also 

increased in years with a ‘green bridge’. Virus survival 

between seasons will increase if hosts such as volunteer 

cereals and their disease-carrying vectors are given the 

opportunity to increase. Aphids will transmit BYDV and 

wheat curl mites carry WSMV from diseased hosts into 

new season crop seedlings if seasonal conditions allow 

for their development.

Host plant susceptibility and resistance 

Some cultivated agricultural plants have been selected 

by breeders or genetically modified for their resistance 

or tolerance to specific insect pests. 

Plants are known to have at least three categories to 

defend themselves from insect attack: 

• antibiosis – the eating of particular plants adversely 

effects the biology of the feeding insect; 

• antixenosis – the plant has characteristics that deters 

insects from feeding; 

• tolerance – plants are able to withstand or quickly 

recover from insect damage. 

High levels of malic acid in most varieties of chickpeas 

is very effective at deterring most insect pests (apart 

from the native budworm) as well as beneficial species. 

Some varieties of narrow-leafed lupins (e.g. Yorrel and 

Tallerack) are susceptible to feeding damage by aphids, 

while others (e.g. Tanjil and Wonga) are considered 

resistant. These host susceptibility characteristics are 

important when considering pest management options. 

Canola is very susceptible to damage by insects and 

is often treated with prophylactic insecticide sprays 

to avoid anticipated damage. The small cotyledons 

of canola and exposed growing tips make it most 

vulnerable to damage. Pulse crops with exposed growing 

points are also vulnerable, but to a lesser extent, as their 

cotyledons are more robust and fleshy. Cereal crops with 

concealed growing points (within their stems) are far less 

vulnerable to insect attack and can tolerate high levels 

of defoliation before plant death occurs or spraying is 

economically justified. 

Genetic engineering techniques have enabled foreign 

genes, such as insecticidal toxins, to be inserted into the 

molecular structure of some agricultural crop species. 

For example, the toxins of Bacillus thuringiensis (Bt) have 

been incorporated into some transgenic varieties of 

cotton and canola. 

Testing of cultivars of transgenic peas that have resistance 

to the pea weevil has provided promising results in 

WA. Research and development of crop cultivars with 

tolerance against pests is less likely while effective and 

cheap insect control is available. 

The susceptibility characteristics of crop types 

are important when considering pest 

management options. 

Stubble retention, minimum tillage and 

changing farming systems 

Increased stubble retention within cropping systems has 

occurred over recent decades largely as a result of: 

• higher yielding crops; 

• increased use of minimum or no till cultivation; 

• fewer or no grazing animals in the farming system; 

• reduced burning of stubble. 

Stubble retention has favoured the increase of some 

pests, such as the bronzed field beetle, weevils, slugs 

and snails, which now have a higher pest status. Bronzed 

field beetle larvae can reach very high numbers in some 

paddocks and have caused significant damage to canola 

in some seasons. This is exacerbated by poor control 

with insecticides. 

Some farmers have addressed excessive stubble 

through burning stubble in autumn, cultivation to 

incorporate stubble into the soil, baling and removing 

straw following harvest and widely dispersing straw 

behind headers. 

Changes in tillage practices have also favoured the 

increase and survival of some residential beneficial 

species such as carabid beetles, predatory mites 

and spiders. However, the benefits of some of these 

natural enemies has been reduced by the over-use of 

‘insurance’ spraying with broad-spectrum insecticides. 

Changing farming systems have resulted in a ‘changing 

pest complex’ with some newer pests becoming more 

troublesome and other pests becoming less problematic. 

For example, the increasing use of swathing as part 

of the harvest system has meant that vagrant insects 

sheltering in swaths have contaminated grain samples. 

Examples of these grain contaminants include the 

bronzed field beetle, vegetable beetles and weevils. 

Grazing 

Grazing management is an effective technique to alter 

the populations of a number of pasture pests. The carryover 

benefits of grazing management will also have 

a large bearing on pest populations in pasture/crop 

rotations. Pests affected by grazing strategies include 

redleggged earth mites, lucerne flea, slugs, snails, 

weevils and other beetles such as false wireworms, 

cockchafers and African black beetle. 


11 



Redlegged earth mite populations are dramatically 

reduced by grazing winter/spring pastures to ‘feed on 

offer’ levels of below 2.5t/ha. This reduction is due to 

the altered pasture habitat and micro-environment 

providing a harsher environment for mite survival, as 

well as direct ingestion by stock. Grazing to these levels 

has the added advantages of: 

• greater pasture utilisation by increased animal 

production; 

• changing pasture composition to favour legumes 

and decreasing grasses; 

• increased legume (sub clover) seed production. 

Intensive spring grazing of selected pasture paddocks 

that will be cropped in the following season is routinely 

carried out by many cereal farmers, with the major 

objective of minimising grass seed production and 

carryover. Less well understood is the added bonus of 

minimising the seasonal carry-over of some pests. 

The benefits of grazing can be equivalent to spraying 

pastures with insecticides. For example mite populations 

have been reduced from approximately 50,000/m 2 to 

less than 102 mites/m 2 in grazing trials at the South 

Stirlings (WA). 

Crop establishment in paddocks following pastures that 

have been intensively grazed in spring to prevent large 

pest carry-over will be less reliant on seed dressings and 

foliar insecticides. 

12 


Chemical control of 

insects and resistance 

issues 

Pesticide usage and IPM 

Pesticides within an IPM framework are the support 

tools used to assist control when biological and cultural 

methods are insufficient. Although chemical control 

is still an important part of an IPM strategy, there 

needs to be a shift from using non selective broadspectrum 

pesticides to more selective alternatives, if 

available. Broad-spectrum or ‘hard’ chemicals (e.g. most 

organophosphate, carbamate and synthetic pyrethroid 

insecticides) have an impact on a wide range of nontarget 

organisms. 

In contrast, selective or ‘soft’ pesticides are active on 

specific pest types (e.g. pirimicarb for aphids, Bt for 

caterpillars) and are effective management tools that 

facilitate – rather than disrupt – the natural biological 

control that already exists. By specifically targeting 

particular pests, they allow beneficial species to remain 

in the system to help further suppress other pests. 

Start to take a whole-systems approach – get to know 

your pest and beneficial invertebrates and the role they 

play. Start to change your tactics – have a closer look 

at alternative control strategies. Think about ‘softer’ 

chemical options and strategic use of broad-spectrum 

pesticides. 

Chemical pesticides such as insecticides, acaricides 

and molluscicides are categorised into various groups 

according to their mode of action and chemical 

composition. They are also referred to by the different 

formulations available (for example: WG = water 

dispersible granules, EC = emulsifiable concentrate). 

Formulations refer to how the chemical’s active 

ingredient is prepared with other substances and made 

available to the end user. It is partially dependant on the 

chemical’s physical properties and influences the mode 

of application. The effectiveness of a pesticide is based 

on its chemical nature, effect on the target pest and the 

environment in which it is applied. 

Chemicals should preferably be applied in 

conjunction with general IPM principles. By law, 

all chemicals must be used in accordance with current 

label instructions. This includes the rates applied and 

adhering to withholding periods for grazing, harvesting 

and fodder production.

Selective insecticides 

The terms ‘soft’ or ‘selective’ are frequently applied to 

pesticides (active ingredient) that kill target pests, but 

have minimal impact on non-target organisms. 

In practice, there are varying degrees of ‘softness’ and 

some insecticides are selective or safe for one group of 

natural enemies but not another (see Table 5.2). 

Unfortunately, soft chemical control options are not 

available for all pests and selective pesticides are not 

always expected to provide 100 % mortality of the 

target pest, but aim to suppress population numbers so 

that biological and cultural methods can regain control. 

In addition to foliar applications, other soft options 

include coating seeds with insecticide (seed dressing) 

prior to sowing. The chemical is translocated into the 

new growing shoots where it provides control of plant 

feeding pests. This control option delays application of 

foliar sprays giving beneficial insects time to build up 

and smaller quantities of chemical are applied per 

hectare. Seed dressings may not give sufficient 

protection against large numbers of pests. For example, 

insecticide seed dressings on canola may not be effective 

against very large populations of redlegged earth mites. 

The routine application of insectide seed treatments 

should not be practiced (i.e. using treated seed every 

year across all paddocks). As with foliar applications, 

pests can develop resistance to chemicals expressed 

through seed treatments. The use of the seed treatments 

should be reserved for paddocks where moderate levels 

of pests are expected. 

Insecticide resistance and tolerance 

Resistance occurs when applications of insecticides 

remove susceptible insects from a population leaving 

only individuals that are resistant. Mating between these 

resistant individuals gradually increases the proportion 

of resistance in the pest population as a whole. 

Eventually this can render an insecticide ineffective, 

leading to control failures in the field. Resistance can be 

due to a trait that is already present in a small portion of 

the pest population or due to a mutation that provides 

resistance. The main mechanisms of resistance are target 

site insensitivity, metabolic resistance, penetration 

resistance, altered behaviour and cross-resistance. 

Bt checklist 

• Spray as late in the day as possible to minimise 

UV breakdown of product. 

• The lack of Bt persistence in the field means 

it must be applied as a uniform spray to leaf 

surfaces where young insect pests are actively 

feeding. 

• Target the small larvae, < 5 mm long (Bt is less 

toxic and effective on larvae > 5 mm). 

• Avoid applying if rain (or overhead irrigation) 

is expected within 24 hours after spraying. 

• Use a wetting agent. 

• Use a high water volume. 

• Make sure your water is not too alkaline. 

A pH of 6.5 to 8.0 is ideal. 

• Make sure you use the appropriate strains and 

formulations suitable for the target pest. 

• Spray out within a few hours of mixing. 

Management of resistance is essential to ensure that 

valuable insecticides remain effective. One of the 

objectives of IPM is to help manage insecticide resistance 

by reducing the overall use of insecticides. This reduces 

the number of selection events. Insecticide resistance 

has evolved in many important pest species within 

Australia including the cotton bollworm, diamondback 

moth, whiteflies, several species of aphids and mites as 

well as many grain storage pests. 

Many pest species possess natural tolerances to several 

chemicals which is unrelated to developed insecticide 

resistance. The exact reasons for these differences in 

tolerance levels between species are unknown. Body 

size and plant hosts have been suggested as factors for 

varying levels of susceptibility to chemicals observed in 

some species. For example, Balaustium and Bryobia mites 

are difficult to control in the field with insecticides used 

to control other mites, such as the redlegged earth mite 

and blue oat mite. Laboratory assays have discovered 

these pests have not developed resistance following 

extensive exposure to insecticides, but rather have a 

naturally high tolerance to multiple chemical classes. 


13 


Table 5.2 Impact of insecticides on natural enemies in crops 

INSECTICIDES 

TOXIC EFFECT ON SPECIFIC NATURAL ENEMIES 

Active Ingredient 

Persistence 

Egg parasitoids 

Hymenoptera 

Larval & pupal 

parasitoids 

Ants 

Predatory beetles 

Predatory bugs 

Lacewings 

Spiders 

Haplothrips 

Toxicity to bees 

Impact rating 

Bacillus thuringiensis (VRP) Very short VL VL VL VL VL VL VL VL VL Very low 

NP virus Very short VL VL VL VL VL VL VL VL VL Very low 

Pirimicarb Short H VL VL VL VL - L VL VL L VL Very low 

Indoxacarb Medium L VL - L VH M - VH L VL - L VL VL H Low 

Metarhizium anisopliae Short L L L L L L L L L Low 

Spinosad Medium H - VH M H VL VL - M VL VL H H Low 

Fipronil (low) Medium VH M VH L L - M VL M VH VH Moderate 

Fipronil (high) Medium VH M - H VH L L - H VL M VH VH Moderate 

Imidacloprid Medium VH L - M H H M - H L L H M Moderate 

Methiocarb Medium VH VH - M VH VH - - VH High 

Methomyl (VRP) Very short H M - H H H - VH L - H M - H M H H High 

Organophosphates (VRP) Short-medium H H VH H M - H L M H H High 

Carbaryl Short - - - H H - - H H High 


Synthetic pyrethroids (VRP) Long VH VH VH VH VH H - VH VH VH H Very High 

VRP = Various Registered products 

Overall impact rating (% reduction in natural enemies following application): 

VL (Very Low) less than 10% H (High) 40-60% 

L (Low) 10-20% VH (Very High) > 60% 

M (Moderate) 20-40% 

A dash (-) indicates no data available 

Persistence of pest control: short = < 3 days; medium = 3-7 days; long = > 10 days 

Pyrethroids may include alpha-cypermethrin, beta-cyfluthrin, cyfluthrin, bifenthrin, esfenvalerate, deltamethrin, lamba-cyhalothrin and gamma-cyhalothrin. 

Organophosphates may include dimethoate, omethoate, profenofos, chlorpyrifos, methidathion, parathion-methyl, diazinon, fenitrothion, maldison, 

phosmet and methamidophos. 

Data sources: 

Cotton Pest Management Guide 2009-2010. Cotton CRC Extension Team, Industry & Investment NSW (2009). 

Toxicity of Tomato & Bell Pepper Insecticides/Miticides to Beneficial Insects. Mark A. Mossler, University of Florida AFAS Extension (2008). 

Koppert Biological Systems (http://side-effects.koppert.nl/). 

HAL project VG04004 “National diamondback moth project: integrating biological chemical and area-wide management of brassica pests”. 

K. Henry (pers. comm.). 

IMPORTANT NOTICE: Although the authors have taken reasonable care in the advice, neither the agencies involved nor their officers accept any liability 

resulting from the interpretation or use of the information set in this document. Information provided is based on the current best information available 

from research data. Users of insecticides should check the label for registration in their particular crop & state, and for rates, pest spectrum, safe handling 

and application details. 

Further information on products can be obtained from the manufacturer. 

14 

SECTION 5 IPM Principles and Case Studies

Conserving the benefits of insecticides 

using an IPM approach 

The routine use of low cost non-selective pesticides can 

be very effective, but indiscriminate use of chemicals can 

also lead to changes in the populations of non-target 

pests and increase potential chemical resistance. Overuse 

of insecticides will also affect the pest/beneficial 

balance and secondary pests may flare up, which can be 

more problematic than the initial pest problem. 

Pest populations are often affected by competition 

from other pests within farming systems. For example, 

applying chemicals with specific activity against 

redlegged earth mite (e.g. bifenthrin) will frequently lead 

to a substantial increase in lucerne flea numbers through 

the removal of competition. In other cases, farmers have 

commented that by increasing their pesticide usage 

they have not solved their pest problems, but have 

selected for pests that are more difficult to kill, such as 

Balaustium mites. 

Non-selective insurance (prophylactic) sprays 

to protect crops ‘just in case’ is not a 

sustainable practice. 

The application of broad-spectrum insecticides in a 

strategic and targeted manner (e.g. seed treatments, 

baits and spot or border spraying rather than widespread 

and insurance applications), will help to avoid 

the detrimental effects on natural enemies and increase 

their benefits. 

Rotation of insecticide groups 

Effective and sustainable insecticide management seeks 

to minimize the selection pressure on invertebrates to 

develop insecticide resistance. Alternations or rotations 

of chemicals from groups with different modes of 

action will ensure that successive generations of the 

pest are not repeatedly treated with the same chemical 

compound. This particularly applies to pests with 

multiple generations in the one season that may require 

several spray applications. 

Rotating use of the commonly used synthetic pyrethroid 

(group 3A) and organophosphate groups (1B) in 

broadacre farming, with other groups (where possible), 

will help to minimise resistance development of target 

and non target pests. 

Other important considerations when chemical 

control is required include: 

• chemical rotation of insecticide groups to reduce the 

pressure of resistance onset; 

• increasing or decreasing the rates of insecticides may 

speed up the development of resistance and in the 

case of increasing rates, could lead to unacceptable 

levels of residues; 

• target the spray application to the most vulnerable 

pest life-stage; 

• spray application techniques (e.g. time of day, nozzle 

selection to avoid drift, good coverage); 

• withholding periods for stock, harvest or fodder 

crops - check label; 

• delay the spraying of a non-selective insecticide for 

as long as possible. 


15 



Area-wide management 

(AWM) 

What is AWM 

Area-wide management (AWM) aims to solve pest 

management problems by coordinating the efforts of 

growers in an area. AWM can take many forms, from 

neighbours discussing how to tackle common pest 

problems through to centrally organized groups that 

implement a coordinated control tactic. AWM may be 

particularly useful for mobile (or transient) pests where 

management at a larger-scale may be more effective 

than a paddock-by-paddock approach (Figure 5.3). 

AWM can also improve our ability to achieve IPM goals. 

IPM principles can be applied at the paddock-scale, but 

some activities may provide better results if used across 

larger areas (Figure 5.4). This is where AWM comes in. 

For example the Australian Plague Locust Commission 

implements an AWM plan to control locust populations. 

These pests are highly mobile, migratory species that 

have the ability to inflict damage across a range of 

agricultural industries in multiple states. A coordinated 

area-specific and time-dependent response to threats 

posed by this pest is required. Another example comes 

from AWM groups that were developed in response 

to cotton bollworm, Helicoverpa armigera, problems 

in cotton on the Darling Downs in Queensland. AWM 

groups had regular meetings before, during and after 

the season to share information. Their objective was 

to reduce the survival of overwintering insecticideresistant 

pupae and reduce damage to susceptible crops 

across a region. 

The benefits of AWM 

AWM can be used to address a number of objectives 

relating to pest problems at a regional or district scale. 

For certain species, a sustained reduction in pest 

populations across time is more likely to be achieved if 

other susceptible crops and pastures surrounding the 

paddock are taken into consideration (Figure 5.3). The 

same is true for increasing the abundance and activity 

of beneficial species. Actions aimed at minimising the 

spread and/or development of insecticide resistance, 

and the spread of diseases vectored by insect pests are 

more likely to provide better long-term results if efforts 

are coordinated across neighbouring growers. 

16 


For which broadacre pests is AWM 

applicable 

AWM works best for species that are mobile, migratory, or 

capable of being transported large distances. For these 

species the home-range of an individual may be much 

larger than a single paddock. Control tactics applied at 

the paddock-scale may only help for short periods of 

time because the species can recolonise quickly. 

There are species that have lower mobilities, but are still 

potential candidates for AWM. Coordinating the timing 

of control tactics may have the biggest impact on these 

species (e.g. species that may have developed resistance 

to insecticides). Table 5.3 is a rough guide that indicates 

which pest species are likely candidates for AWM. If 

you are experiencing problems with these species you 

should consider an AWM approach. 

First steps towards AWM 

Here is a general guide to the steps involved in 

developing an AWM approach. 

Step 1. Define the problem 

What is the pest problem Is it high abundance 

of a pest causing direct damage and yield loss, 

or perhaps a pest causing damage at critical 

times of crop growth or establishment Is 

there control failure that may be linked to pest 

resistance to an insecticide 

Step 2. Identify the objective 

Minimising crop damage and increasing profit 

may be the ultimate objective of AWM, but what 

are the specific goals of an AWM approach 

They may include reducing pest densities over 

the long-term, slowing new pest arrivals into 

the crop, slowing the spread of insecticide 

resistance, stopping disease transmission, or 

making sure pests are at low levels during a 

critical crop growth stage. 

Step 3. Where, when, and how big is the 

problem 

Identify what crops this pest attacks. Determine 

how many growers in the area are experiencing 

a similar problem. Examine maps and assess 

the location of susceptible crop-types now or 

in future plantings, the location of large areas of 

other host plants such as pasture or weeds, and 

any likely sources of beneficial species.

Step 4. What are the management options 

Consider a range of management options that 

include pre-season actions such as destroying 

weeds that host pests between seasons, 

sometimes known as the ‘green bridge’ (see 

p 10 this section). Make sure you can identify the 

pest and the relevant beneficial species in the 

field. Know what insecticides work best, their 

availability, and the economic threshold (see 

p 9, section 6) for spraying. Think about cultural 

control options including grazing pastures and 

the timing of crop harvest (see p 11 this section). 

Step 5. Gain commitment from participants 

Make sure all growers are committed to the 

plan and feel confident in the actions they 

need to take. It may help to ask your local 

district agronomist (DA) or trusted consultant 

to coordinate the group’s activities. Plan a 

monitoring strategy that is simple to use and 

discuss how results will be communicated to 

the group. 

Step 6. Monitoring, recording and 

communicating throughout the season 

As the season progresses catch up regularly 

to let each other know how it’s going. At the 

end of the season get together and reflect on 

the season and discuss what worked and what 

could be improved. 

AWM examples 

1. Green peach aphid (see p 41, section 4) is a highly 

mobile species that can move rapidly into a region 

and has shown resistance to insecticides. The 

objective of an AWM plan in your region may be to 

reduce the populations of over-summering aphids 

on weeds and slow the spread of resistance. Before 

the season starts get together as a group and map 

out the likely locations of crops at risk (canola and 

pulse crops). Determine if resistance is present in 

your region and to what chemicals (you may need to 

send samples to your Department of Agriculture or 

Primary Industries). 

Clarify the identification of this species as it can 

easily be confused with other aphid species. Assess 

the over-summering weather conditions and, if and 

where, a ‘green bridge’ is present. Before planting 

discuss how the group will communicate during the 

season and plan some management options (see 

p 44, section 4 ). During the season monitor and 

record as planned, and compare pest levels to 

thresholds of economic injury. Keep regular contact 

with the group and share information on where you 

do and don’t see aphids and if beneficial species are 

present and active. 

If pest levels reach threshold, hence a spray is 

required, use a selective insecticide that doesn’t 

disrupt beneficial species. Before spraying, check 

the mode of action, and develop a plan for rotating 

different chemical groups throughout the season. 

After applying an insecticide, monitor to assess if the 

spray(s) worked, and watch for ‘flaring’ of secondary 

pests. 

2. Native budworm (see p 11, section 4) is a pest that 

migrates from inland Australia into agricultural 

regions and its life-cycle is well known. The larvae 

cause damage to pulses and canola but will also 

damage other crops and pastures as it feeds on a 

wide variety of host plants. When developing an 

AWM plan for this species, (in addition to the steps 

detailed in example 1) you could use pheromone 

traps (see p 6, section 6) to monitor for influxes. Traps 

are placed across a wide area and checked weekly. 

The information is communicated to the AWM 

group (or to a pest alert service such the PestFax/ 

PestFacts services) where all trap information is 

collated and disseminated to subscribers. This is 

a great early-warning system, and can signal the 

need for more frequent monitoring for the larval 

stages that are most damaging. Crop monitoring to 

determine whether the pest has reached threshold 

can be conducted using a sweep net (see p 5, 

section 6). 


17 


Figure 5.3. Diagram illustrating the concept of AWM. 

A. indicates a hypothetical pest outbreak. 

B. indicates a situation where a pest is controlled on a paddock-by-paddock basis. 

C. indicates AWM where all habitat-patches are controlled in a co-ordinated fashion. 


Figure 5.4 How IPM and AWM work together to achieve pest management at larger scales 

(Source: L. Wilson, pers. comm.). 

18 

Field Farm Groups Region 


IPM IPM Groups AWM

Table 5.3 Pest species for which an AWM approach may prove more useful than a paddock-by-paddock approach. 

Mobility and outbreak frequency across large areas: 

*** high; **intermediate; * low; too little information for confirmation. 

Insecticide Resistance: 

recorded in Australian grain crops; ✗ not recorded 

AWM: 

AWM may bring benefits over a paddock-by-paddock approach; 

~ AWM provide some benefit but other species are high priority for developing AWM; 

✗ little added benefit from AWM. 

PESTS 

MOBILITY 

OUTBREAK 

FREQUENCY 

INSECTICIDE 

RESISTANCE 

green peach aphid *** *** 

oat aphid *** *** ✗ 

rutherglen bug *** ** ✗ 

diamond back moth *** *** 

budworm (Helicoverpa spp.) *** *** 

Australian plague locust *** * ✗ 

redlegged earth mite ** *** 

Other aphids (corn, spotted alfalfa, 

blue green, pea) 

*** ** ✗ ~ 

green mirid *** * ✗ ~ 

cockchafers ** ** ✗ ~ 

AWM 

wheat curl mite ** *** 1 ✗ ~ 2 

Bryobia mite or clover mite ** ** ✗ ~ 

two-spotted mite * * ✗ ~ 

Balaustium mite ** *** ✗ ~ 

blue oat mite ** *** ✗ ~ 

cutworms *** ** ✗ ~ 

armyworms *** ** ✗ ~ 

lucerne seed web moth *** ** ✗ ~ 

snails ** ** ✗ ~ 

thrips (western flower, onion, plague thrips) ** * ~ 

lesser budworm (Heliothis punctifera) ** * ✗ ✗ 

leafhoppers * ✗ ✗ 

true and false wireworms ** ** ✗ ✗ 

weevils * ✗ ✗ 

European earwig ** ** ✗ ✗ 

lucerne flea * *** ✗ ✗ 

brown wheat mite ** * ✗ ✗ 

slugs * *** ✗ ✗ 

black Portugese millipede * ✗ ✗ 

1 Can reach high abundance in local outbreaks 

2 Controlling the ‘green bridge’ may be important for reducing disease transmission by this pest 

(Source: S. Macfadyen, N. Schellhorn, J. Holloway, P. Umina and G. Fitt, pers. comm.) 


19 


IPM in Practice: Case Studies 

Case study 1 

Shelterbelts in agricultural landscapes suppress invertebrate pests 

Location: Western district and Northern Country, Victoria 

Date: 2003-2004 

Lead Researcher: Angelos Tsitsilas (CESAR) 

Summary: Landscape ecology can be manipulated in 

such a way that promotes natural enemies and aids IPM 

strategies. The use of windbreaks in providing a reservoir 

for key functional invertebrates and their impact on pest 

species was investigated. Invertebrates along transects 

running from replicated shelterbelts into pastures were 

sampled. Numbers of redlegged earth mites, blue oat 

mites and lucerne fleas were low within shelterbelts. 

Numbers were typically lower adjacent to shelterbelts 

compared with 50 m into the pasture, an effect that 

was much more apparent when shelterbelts carried a 

groundcover of high grass (>30 cm). 

The windbreak composition/ecology is important, with 

long grasses and shrubs offering complexity, which 

in turn provides more niches for important beneficial 

invertebrates such as spiders, predatory mites, 

parasitoids and pollinators. Thus, relatively simple 

measures, such as the management of a windbreak 

understorey can be used to maximise the use of 

naturally occurring biological control and have a direct 

negative impact on pest invertebrates. 

(Adapted from Tsitsilas et al., 2006. Australian Journal of Experimental 

Agriculture 46: 1379-1388). 


Average numbers per sample 

Number of pest species in windbreaks and in adjoining pasture. Transect points are marked as negative when extending into the windbreak and positive 

into the adjacent pasture. Closed squares and solid lines = simple shelterbelts. Crosses and dashed lines = complex shelterbelts. Error bars = standard errors 

for transect points. (Data from Tsitsilas et al., 2006 AJEA 46: 1379-1388). 

20 

Hamilton Hamilton Hamilton 

Streatham 

Redlegged earth mites Blue oat mites Lucerne fleas 


Streatham 

Streatham

Case study 2 

Selective chemicals and their role in broadacre cropping 

Location: Northern Country, Victoria 

Date: 2008 

Lead Researcher: Stuart McColl (CESAR) 

Summary: Although chemical control is still an 

important part of an IPM strategy, there needs to be a 

shift from using broad-spectrum pesticides to more 

selective alternatives if they are available. Broadspectrum 

chemicals invariably kill non-target organisms, 

whereas the use of more selective or ‘soft’ pesticides 

is an effective management tool that facilitates – rather 

than disrupts – the natural biological control that 

already exists. By specifically targeting plant-feeding 

invertebrates, they allow beneficial species to remain in 

the system to help suppress pest numbers. 

A trial was performed in a canola crop in late spring 

to examine the efficacy of the selective aphicide 

(pirimicarb) against the cabbage aphid, Brevicoryne 

brassicae. This was compared with a conventional 

broad-spectrum insecticide. Pirimicarb provided very 

good control of cabbage aphids up to 25 days after 

application. Pirimicarb also showed little negative 

effect on a number of important beneficial predatory 

invertebrates, including lady beetles, lacewings and 

hoverflies. 

(Unpublished preliminary findings from S. McColl and P. Umina). 

Preliminary field trials assessing the ‘soft’ chemical pirimicarb, for the control of cabbage aphids in a late-spring canola crop at Elmore, Victoria, in 2008. 

Control = unsprayed canola. DAT = days after treatment application. Error bars = standard error of the mean. (McColl & Umina, unpublished). 


21 


Case study 3 

Creating pest problems and losing money with broad-spectrum pesticides 

Location: South Burnett region, Queensland 

Date: 2001 

Lead Researcher: Hugh Brier (DEEDI) 


Summary: Mirids are major pests of summer pulses, such 

as mungbeans, attacking buds, flowers and small pods. 

Despite being quite damaging to crops, the threshold 

levels for mirids (0.3 - 0.5 mirids/m 2 ) are low because 

the most effective pesticides, such as dimethoate, are 

inexpensive. As a result, most crops are sprayed at least 

once for mirids, often at the first sight of the pest at early 

flowering. These applications are disruptive to beneficial 

insects (predatory bugs and beetles, parasitic flies 

and wasps). It is therefore not surprising that there are 

reports of outbreaks of Helicoverpa armigera within 7-14 

days of mirid spraying. Helicoverpa armigera is a major 

caterpillar pest of mungbeans. 

Data presented from a mirid management trial confirms 

that a single dimethoate spray can initiate an abovethreshold 

outbreak of H. armigera (Figure A). While 

mirids were adequately controlled by dimethoate in this 

trial, populations of H. armigera increased significantly to 

above threshold within 10 days of spraying. 

Figure A. Data showing pest population trends following a single application 

of dimethoate against mirids in flowering/early podding mungbeans. 

D500 = dimethoate @ 500mL /ha 

22 


In contrast, H. armigera populations in unsprayed plots 

remained well below threshold. This trend is explained 

by a 50% reduction in beneficial activity in dimethoatesprayed 

plots, and a negative correlation between 

beneficial activity (mainly predatory bugs, beetles and 

spiders) and H. armigera activity in this trial. 

The economic implications for the trial crop in question 

are shown in Figure B. The expected crop value if there 

was no pest activity is $660/ha, based on $600/t and 

a yield of 1.1t/ha. If the pests are untreated, economic 

threshold models predict crop value will be reduced to 

$609/ha. When the ‘above threshold’ mirid population 

is controlled, the predicted crop value in the absence of 

H. armigera increases to $645/ha. However, if the 

insecticide application results in an increase in 

H. armigera the crop value declines to $596/ha. While 

H. armigera may not be flared in every mungbean crop 

sprayed for mirids, the above scenario illustrates how a 

single spray of a non-selective pesticide can trigger an 

outbreak of another pest, reducing the crop’s net return 

to growers. 

(Adapted from Brier HB, 2009. Final Report for GRDC project DAQ00086). 

Figure B: Crop values ($/ha) for different spray treatment scenarios 

in mungbeans with a yield of 1.1 t/ha and a crop value of $600/t. 

D500 = dimethoate @ 500mL /ha, S400 = Steward (indoxacarb) @ 

400mL/ha, helis = Helicoverpa armigera. The calculations assume 

application costs of $5/ha with a ground rig.

Case study 4 

Seed dressings protect emerging canola seedlings from pest attack 

Location: Western district, Victoria 

Date: 2008 

Lead Researcher: Paul Umina (CESAR) 

Summary: Seed treatments provide targeted control 

of many invertebrate pests. They offer protection at the 

critical establishment phase of crops and can often delay 

application of foliar sprays giving beneficial species 

time to increase in number. A research trial was 

performed in an emerging canola crop under attack 

from the redlegged earth mite (Halotydeus destructor) 

and blue oat mite (Penthaleus sp.). 

In this trial, plots containing both insecticide seed 

treatments did not require foliar applications to control 

any crop establishment pests. However, it is important 

to note that seed dressings may not give sufficient 

protection against pests, including earth mites, when 

found in large numbers. Monitoring crops (even those 

sown with insecticide treated seed) during the first few 

weeks of emergence is critical. 

Two registered seed dressings, imidacloprid (Gaucho®) 

and fipronil (Cosmos®), were compared with untreated 

canola seed. Untreated control plots had significantly 

fewer plants per square metre, higher plant damage 

scores and lower crop vigour scores than all insecticide 

seed treated plots at all sampling dates. Fewer pest mites 

were found in the plots sown with insecticide-treated 

seed and significant benefits in yield were observed in 

these plots compared with the untreated controls. 

A) B) 

(Unpublished preliminary findings from P. Umina and S. McColl) 

Preliminary field trials assessing the effect of seed treatments as a means of protecting emerging canola at Ballarat, Victoria in 2008. A) Average number 

of seedlings per metre square at 7 days, 14 days and 28 days after crop emergence. B) Average number of redlegged earth mites per metre square at 7 days 

and 14 days after crop emergence. Control = untreated seed. Error bars = standard error of the mean. (McColl & Umina, unpublished). 


23 


Case Study 5 

The effects of grazing on redlegged earth mite populations 

Location - South Stirlings, Mt. Barker and North Dandalup, Western Australia 

Date: 1992 - 1994 

Lead Researcher : Phil Michael (DAFWA) 


Summary: Redlegged earth mites are a major pest of 

pastures and seedling crops in southern Australia. Their 

impact on agricultural productivity is related to their 

pest abundance which in turn is related to season and 

paddock habitat. Pasture production with dominance 

of broad-leafed species such as clover and capeweed is 

particularly conducive to redlegged earth mite increase. 

Farming systems in high rainfall areas of Western 

Australia often have several years of pasture production 

followed by a cropping phase, such as canola. In this 

situation there is a high risk of seedling damage and 

heavy reliance on insecticides to protect seedling canola 

against RLEM damage. 

Research was conducted over a three year period on 

three separate locations to investigate the effects of 

intensive grazing levels and pest control on pasture 

growth and composition, pest populations and animal 

productivity. Three grazing treatments were set-up 

to maintain pasture feed on offer (FOO) levels of 1.4 t 

DM/ha, 2.8 t DM/ha and set stocked (S/S) at the district 

average stocking rate for each locality, being South 

Stirlings, Mount Barker and North Dandalup. 

Merino wethers were replaced as one year olds, each 

year and at each site. Additional merino wethers from 

outside the experimental paddocks were added or 

removed from trial plots as required to maintain the 

required treatment feed on offer levels. At each sites, 

the grazing treatments were randomly allocated within 

3 blocks, with and without pest control (total of 18 

plots). The fenced plots ranged from 0.5 – 1.2 ha for 

differentially grazed treatments and 1.0 to 1.6 ha for set 

stocked treatments. 

45000 

40000 

35000 

30000 

25000 

20000 

15000 

10000 

5000 

0 

Figure A: The effects of grazing to 1.4, 2.8 t DM/ha or set stocked on 

spring (year 1) redlegged earth mite numbers per m² at three sites. 

SST=South Stirling, MB=Mount Barker, ND=North Dandelup 

24 

351 161 351 

SST MB ND 


FOO 1.4 t/ha 

FOO 2.8 t/ha 

Set Stocked 

Results showed that grazing was clearly a major factor in 

affecting RLEM populations over the three seasons and 

sites. 

Reductions in mite numbers with grazing were 

repeatedly seen with more than ten times the number 

of RLEM often found in pasture clumps compared with 

adjacent “patched grazed” areas. A combination of 

reasons is involved in the reduction including ingestion 

of eggs and mites by grazing stock, trampling and 

creating a less favourable / more exposed environment 

for the mites. 

Importantly there was a strong correlation between 

spring and autumn RLEM populations with carryover 

populations remaining very low in the 1.4 and 2.8 t DM/ 

ha treatments compared to set stocked plots shown in 

the graphs below (Figures A and B). The low levels of 

mites found in the spring and autumn populations of 

the 1.4t DM/ha treatments were at levels approaching 

those achieved by repeated spray applications in the 

treated plots (not shown as they were close to zero). 

The research has demonstrated that strategic intensive 

grazing can be confidently used as an IPM management 

tool to manage RLEM populations within the pasture 

phase and between seasons perhaps prior to a cropping 

season, with minimal use of insecticides. 

45000 

40000 

35000 

30000 

25000 

20000 

15000 

10000 

5000 

0 

420 

2375 

SST MB ND 

Figure B: The effects of grazing to 1.4, 2.8 t DM/ha or set stocked on the 

following autumn (year 2) redlegged earth mite numbers per m² at 

three sites. SST=South Stirling, MB=Mount Barker, ND=North Dandelup 

Note - The lower levels of autumn mites at North Dandalup (ND) 

was because of overgrazing during summer. 

16 

FOO 1.4 t/ha 

FOO 2.8 t/ha 

Set Stocked

6 

Monitoring, Record Keeping, 

Sampling Techniques 


Monitoring

SECTION 6 

Monitoring, Record Keeping, 

Sampling Techniques 


Introduction ....................................................... 2 

Factors to consider for effective monitoring. .............................2 

Monitoring kit checklist . ................................................2 

Frequency and timing ..................................................2 

Unbiased and random sampling procedure .............................3 

Plant damage symptoms ...............................................3 

Sample size and number . ...............................................3 

Defined sampling area .................................................3 

Confidence in monitoring crops . ........................................4 

Sampling techniques ............................................... 4 

Visual observations .....................................................4 

Suction sampling .......................................................5 

Sweep net . .............................................................5 

Cut and bash ...........................................................5 

Brushing or beat sheet . .................................................5 

Sampling with traps 

Pitfall traps, Pheromone traps, Sticky traps, Light traps, 

Baiting & shelter/refuge traps ........................................6 

Effective monitoring and record keeping ................................7 

Sending samples for identification ......................................8 

Economic thresholds ............................................... 9 

Yield-based thresholds, Quality-based or preventative thresholds, 

Defoliation thresholds & Nominal thresholds .........................9 

More factors to consider .............................................. 10 

Multi-pest situations . ................................................. 10 

Control decision processes . ............................................11 

Putting it all together . ............................................. 11 

Important factors to consider before deciding to control pests ..........11 

Outcomes of pest control decisions ....................................12 

Figures and Tables 

Figure 6.1 Economic pest thresholds guiding control decisions . .............9 

Figure 6.2 Percent defoliation of soybean leaflets attacked by Helicoverpa larvae 10 

Table 6.1 Row length estimates for different crop row spacings .............4 

Table 6.2 Crop monitoring record sheet . .................................13 

Table 6.3 Check list of broadacre pests occurring in southern Australia .....15 

Table 6.4 Checklist of common pest in southern Australia by crop type .....19 

SECTION 6 MONITORING, RECORD KEEPING, SAMPLING TECHNIQUES AND ECONOMIC THRESHOLDS 

1 


Introduction 

Monitoring pest and beneficial species is one of the 

most important tools for making informed decisions 

around pest management. 

Monitoring kit - checklist 


Frequent, accurate and timely crop monitoring will allow 

you to: 

• be aware of pest and beneficial abundance, and their 

development and impact on crops and pastures; 

• maximise the chance of effective and timely pest 

control; 

• have the confidence that chemical control is either 

needed or unwarranted. 

When inspecting crops, developing a monitoring kit can 

be useful (see checklist opposite). 

There are a range of monitoring methods available, 

depending on the type of invertebrates you are looking 

for. Knowledge of the pest’s lifecycle and habits, as well 

as the crop growth stages that are most vulnerable to 

damage, will allow you to choose the most appropriate 

technique. 

Record keeping is useful for decision-making. Monitoring 

results should be recorded for each visual observation 

and sampling technique. Use the supplied monitoring 

record sheet in this manual or draw up a similar form 

that suits your specific needs. 

Factors to consider for effective 

monitoring 

• What pest is causing the damage 

• Is there more than one pest involved 

• Where are they hiding 

• How many are there 

• Are there any beneficial invertebrates 

Invertebrate numbers should be recorded so they can 

be compared with known economic threshold levels. 

2 

Frequency and timing 


• recording sheet (Table 6.2 p. 13) and pencil 

• hand lens 

• ruler to measure invertebrates and row widths 

• shovel 

• sweep net 

• pitfall trap (and liquid solution) 

• white plastic containers or trays (e.g. ice cream 

containers) 

• sample jars (non-crushable and some with small 

vent holes for live specimens) 

• plastic bags 

• camera 

• torch - for night inspections 

• sieve 

In many cases, it doesn’t take too much longer to 

check crops and pastures systematically and to 

record observations, than some informal monitoring 

approaches. In cases where pests species are in low 

numbers and/or are hiding during the day, allow 

sufficient time to complete thorough checks. 

It is essential to monitor crops during critical crop stages 

such as: 

• pre-sowing; 

• first few weeks of emergence; 

• prior to and during pod/grain formation. 

Management and control decisions should be 

based on timely monitoring throughout the season 

to detect early damage and assess the impact of 

beneficial invertebrates. 

Insect activity, and hence monitoring, will be influenced 

by the time of day and weather conditions. Late morning 

(warmth increases movement) or late afternoon 

(nocturnal insects become active) are often good times 

to look. Invertebrates will often move up or down 

the plant canopy and on or near the soil surface with 

changes in daily temperature, rainfall and wind events.

Unbiased and random sampling 

procedures 

Invertebrate pests can be unevenly distributed (patchy) 

across a paddock and go unnoticed when monitoring, 

especially when plant damage symptoms are relatively 

minor. Representative parts of a paddock should be 

checked to account for this. 

Inspect in an unbiased random pattern covering 

representative parts of the crop. 

The pattern used for inspecting a paddock will depend 

on what crops are growing and what stage they are at. 

In small paddocks, walking a W-pattern over the whole 

area, selecting random plants along the way and looking 

for symptoms and damage is recommended. 

Determine if the pest damage is: 

• only along the crop edges or on one side where it adjoins 

paddocks that may be the source of migrating pests; 

• in patches that are scattered throughout the crop; 

• in rows that follow previous cultivation or header trails; 

• from a pest that may be hiding during the day. 

Turning over wood, stubble, rocks or using a tile trap 

may catch the culprit. 

Sample size and number 

In general, taking more smaller samples across a wide 

area is better than taking just a few large samples. For 

example, inspecting many individual plants for aphids or 

budworm in spring over a wide area is far more accurate 

than inspecting one square metre at random. 

In large paddocks at crop seedling stage, driving or 

using a motor bike to cover the whole paddock using a 

‘zig-zag’ pattern is more practical. 

• Randomly pick five sampling stops (positions) along 

the zig-zag line. 

• Check plants within an appropriate radius distance 

(e.g. five metres) around each sampling stop. 

• Avoid focusing on small unrepresentative areas as 

they can give biased results (e.g. most damage may 

be on one crop edge or near a grassy shelterbelt). 

In advanced crops in large paddocks, driving across 

is impractical and walking takes too long. It is often best 

to drive along firebreaks, vehicle tracks or adjoining 

paddocks, stopping at representative spots around the 

paddock. Walk into the crop at least 20 m and sample 

there, to be sure you are not just looking at an edge effect. 

Plant damage symptoms 

Close inspection on or near damaged plants found within 

a crop is a good starting point. Thoroughly investigate 

any obvious bare patches, damage symptoms or 

thinning of a crop/pasture and determine the cause, 

extent and distribution of the damage. 

Pest damage keys (section 3, p. 18) are a good aid to 

identify which invertebrates could be present using 

descriptions of their typical feeding patterns and their 

natural behaviour (e.g. ground dwelling, found on upper 

leaves or hiding during the day). 

If no pests are immediately obvious after close 

inspection, then the following techniques in this section 

could be used, depending on the time of year and crop 

type. 

The numbers of samples required and the level of 

confidence obtained is linked to population levels. If 

populations are well above the economic thresholds (ET) or 

well below ET, then fewer samples need to be taken. When 

populations are near threshold levels, a larger number of 

samples will be required to have confidence in the results. 

Defined sampling area 

Using a defined sampling area often helps to focus 

attention and provide a measure for calculations of 

abundance. For example: 

• Numbers of insects per leaf/growing point 

(e.g. mites per seedling, aphids per flowering spike 

in canola or cereal aphids per tiller in cereals. For 

assessments of cereal aphids, it is easier to select 

random tillers and cut them off near ground level 

with a sharp knife or cutters, then raise them up to 

eye level for inspection. The single tillers can then 

be inspected and turned over in good light to view 

insects hidden under leaf blades). 

• A wire frame that is a defined area (e.g. 1/10 m) 

provides a measure for calculations of abundance. 

This can be used in established pasture paddocks 

that have relatively uniform coverage. The sample 

area provides a manageable way of counting plants, 

assessing damage or taking cuts for biomass measure. 

• Monitoring stations marked by a peg or flagging tape 

can be placed in designated spots for fixed referral 

points to look at plant numbers, insect numbers and 

plant damage changes over time. 

• Using a defined-length pole is useful to assess plant 

numbers and damage along row crops (e.g. number 

of plants per unit area). The size of the sampling area 

is best modified to suit the width of the crop rows 

examined. Table 6.1 (page 4) provides row length 

estimates for different crop row spacings. The 1/10 m² 

area is based on distance along a row and the interrow 

gap. 


3 



Table 6.1 Row length estimates for different crop 

row spacings 

4 

Crop row spacing 

(cm) 

Relationship of crop row width 

for a sampling area 1/10 m² 

Row length (cm) 

(Row length x inter-row gap = 1/10 m²) 

100 10 

35.5 28.2 

30 33.3 

25 40.0 

20 50.0 

17.5 57.1 

15 66.7 

10 100 

5 200 

Confidence in monitoring crops 

This is influenced by: 

• Sampling technique. This will vary depending on 

the time of year and crop type; 

• Allowing sufficient time to accurately assess (and 

identify) pest levels. It may take more than one 

hour to accurately assess a large paddock for pest 

populations that are close to ET levels. It will take less 

time if levels are well above or well below ET; 

• Frequency of monitoring. Infrequent checks or 

missing the critical periods can be costly and give the 

false impression that pests have appeared suddenly, 

when in reality, they may have been building up 

over several weeks. For example, a native budworm 

moth flight may have gone unnoticed and the 

resultant small larvae may have been present in a 

pea crop weeks before flowering. Extensive damage 

to newly formed field pea pods by large larvae would 

have easily been identified if earlier pre-flowering 

sweep net sampling was performed; 

• Proportioning damage where there are a number 

of issues. Crops can show signs of invertebrate 

feeding damage together with one or more other 

stresses such as nutrient deficiency, disease, frost 

damage and moisture stress. 

Confidence in monitoring will result in improved 

IPM decision making. 

Sampling techniques 


Visual observations 

Finding pests can sometimes be difficult for the 

inexperienced observer because of their small size, 

inconspicuous colours and/or because they hide by day. 

Some tips are provided below to assist with monitoring. 

• Digging over the upper soil surface to uncover 

hidden pests (e.g. cutworm larvae, false wireworms 

and cockchafers). A suitable-sized soil sieve can 

be useful to separate insects from dry soil. Inspect 

underground root systems and soil beneath plants 

showing poor growth symptoms and yellowing for 

underground species (e.g. Desiantha larvae or adult 

African black beetles). 

• Tiller and flower inspections. While walking 

through a crop, inspect random cereal tillers, or canola 

or lupin flowering and podding spikes. Record each 

observation point to work out an average number per 

tiller or flower spike. Use especially for monitoring 

aphid populations. Length of stem covered in aphids 

can also be recorded (see p. 7). 

• Physically uncover by sifting through plant material 

such as stubble and leaf litter for ground-dwelling 

insects (e.g. wireworms, weevils, earwigs and slugs) 

and also in the inter-row spaces (e.g. armyworms). 

Turn over bits of wood, stones and soil clods to find 

sheltering pests (e.g. weevils and slugs). 

• Spraying small patches of crop (e.g. few square 

metres) with an insecticide can kill off whatever pests 

are in the sample area. Inspection of this sprayed area 

early on the following day may expose hidden pests 

(e.g. weevils, false wireworms and cutworm). Laying 

trails of poison baits overnight and checking early on 

the following morning will reveal areas of a paddock 

where snails and slugs are most prevalent.

Suction sampling 

Suction sampling is a sampling method that uses a 

vacuum machine (sometimes called D-vac). Suction 

sampling is most effective in dry, upright vegetation 


Sampling with traps 

Some invertebrate species can be easily attracted and/or 

captured through the use of traps and chemical or visual 

lures. The results of monitoring in this way can provide 

general evidence of pest presence and activity. 

Pitfall traps are containers that are dug 

into the soil, their open-mouthed tops 

flush with the ground surface. They 

are used to capture invertebrates that crawl over the soil 

surface and fall into the opening. Various containers (e.g. 

plastic cups) can be used for pitfall traps, which usually 

have fluid (detergent/water 

mix or glycol) in the bottom. 

Ensure that there is no ‘edge 

effect’ and that the trap is 

placed flush with the soil 

surface, otherwise smaller 

species may walk around 

the trap. 

Main species targeted: most ground-dwelling 

invertebrates, especially beetles, mites, spiders and ants. 

Effective in autumn through spring. 

Pheromone traps use highly specific 

odours (pheromones) that have the 

same function of chemical signals emitted by the 

targeted female species to attract a mate. As they use 

female-emitted compounds, they only catch males. They 

are best suited to signalling the arrival of significant peaks 

or influxes in moths over broad areas. They are usually 

unreliable indicators of pest abundance and sampling 

of crops using other methods (e.g. a sweep net) is 

advised in conjunction with pheromone trapping. 

Main species targeted: moths. Pheromone lures are 

available for a number of moth species (e.g. Helicoverpa 

spp). Most effective in spring or before anticipated moth 

flights. 

6 


Sticky traps are usually made from a yellow 

cardboard material in varying shapes and sizes 

and have one or more surfaces coated with 

a non-drying sticky substance. They can be 

attached to a post and placed in a paddock (usually just 

above the crop canopy) to catch flying insects. 

Main species targeted: aphids and wasps. Effective 

in autumn through spring. They can be useful for early 

detection of winged aphid arrival into crops. 

Light traps catch many species, but generally 

not in high enough numbers to have an 

impact on pest populations. As samples are so 

diverse (i.e. large numbers of pest, beneficial 

and non–target species), they are often impractical for 

estimating numbers. Farmers will often notice large 

numbers of insects attracted to house or shed lights on 

warm evenings. Inspecting some of the dead insects 

that drop beneath the light can give an indication of the 

movement of pest and/or beneficial species. 

Main species targeted: moths, beetles and bugs. 

Effective in spring and summer. 

Baiting and shelter/refuge traps 

Baits can be placed under refuges or shelters, such as 

large ceramic tiles, where crawling invertebrates may 

hide. After a few days, count the number of pests under 

and around each square, preferably before midday and 

after moist conditions. Be aware that baits which actively 

attract slugs and snails can result in numbers which are 

artificially high. It is important to sample representative 

parts of each paddock because the distribution of 

pests can be patchy. Alternatively, shelters can be used 

without baits to provide a more accurate indication of 

the numbers present in a paddock. Wet carpet squares 

and hessian sacks can also be used, but provide a less 

suitable refuge because they heat up during the day 

and retain less moisture. Materials used as refuge traps 

should at least be 30 cm x 30 cm. Place traps when the 

soil surface is visibly wet, allowing a small space for 

invertebrates to squeeze underneath. 

Seed-germinating baits are swollen germinating seeds 

that are buried in the soil. The chemicals released from 

the seed during the germination process can attract 

pests. This is a quick and effective method to assess 

potential soil-inhabiting pests that attack seeds and 

seedlings. Remember to mark where you buried the 

seeds so you can find them again. 

Main species targeted: nocturnal and ground-dwelling 

species such as slugs, snails, cutworms, weevils and earwigs.

Effective monitoring and 

record-keeping 

Monitoring of pest abundance and damage should 

be recorded together with their distribution within 

crops. This should be achieved through frequent and 

unbiased (random) monitoring across representative 

parts of each paddock. Records should also be kept of 

beneficial species (diversity and relative abundance), 

as well as other general field information such as crop 

health/stage, paddock history, weather patterns and the 

presence of weeds. 

Use the monitoring record sheet supplied 

in this section (page 13). 

Alternatively you can draw up a similar recording sheet 

that suits your needs. Monitoring sheets should at least 

indicate the numbers of insects found (including details 

on numbers of adults and immature stages), date, 

time, weather conditions and crop observations. This is 

especially critical if an insecticide treatment is required, 

so an accurate assessment can be made post-chemical 

application. 

Details of spray operations should include date, time 

of day, conditions (wind speed, temperature and 

humidity), product used, product rate and water rate, 

method of application and other relevant details. Nil or 

low invertebrate numbers are also important to record. 

Accurate records are useful for future reference 

to review the success of control measures, help 

refine thresholds and management guidelines 

applicable to localised situations and practices, 

plus provide ‘proof of absence’ of exotic pests 

for market access. 

Spring monitoring for aphids causing 

feeding damage 

Aphids can have a patchy distribution within 

crops. Their habit of forming dense colonies 

in clusters often results in high numbers on 

a single plant whilst the neighbouring plants 

have few or no aphids. Several separate sites 

within a paddock should be checked to account 

for potential patchy distributions and to avoid 

under- or over-estimating aphid populations. 

Canola crops – check at least five separate 

representative locations within a paddock and 

look for aphids on a minimum of 20 random 

flowering spikes at each point. If more than 20% 

of these are infested with aphids, control should 

be considered. 

Cereal crops – check at least five separate 

representative locations within a paddock and 

look for aphids on randomly picked tillers. If 50% 

or more of these tillers are infested with 15 or 

more aphids and crops have a yield expectation of 

at least 3 t/ha then control should be considered. 

Remember that other factors can contribute to 

an increased risk of economic yield loss including 

poor finishing rains and crops already under 

some degree of stress. 


7 


Sending samples for identification 


8 

Where there is uncertainty around identification 

of a particular pest or beneficial invertebrate, 

seek assistance from your local consultant, a 

departmental entomologist or through your 

regional PestFax/PestFacts services (see section 4 

for more information). 

Specimens should be undamaged and in an 

appropriate developmental stage for reliable 

identification. Some species show considerable 

variation in size, colour, shape and appearance 

between males and females so, where possible, 10- 

15 fresh specimens should be collected. 

Data collection 

Adequate information is essential to aid in successful 

identification and is important in cases where the 

specimen may become part of an insect collection. 

Collection data labels should be written with pencil 

as ink may run or ruin the sample. The minimum 

information provided should be date, locality, 

collector name(s), host plant and description of 

damage (type and extent). 

Specimen preparation 

Fresh healthy specimens should be placed in a noncrushable 

plastic container with small pinholes in 

the lid for ventilation. A small quantity of food on 

which the insects were feeding should be placed 

in the container with a piece of tissue to absorb 

any excess moisture. If strong-jawed predatory 

insects such as ground beetles or scarab larvae are 

collected, it is best to place them in separate jars 

as they may damage each other. Live samples are 

easier to identify and this is the preferred method 

of receiving specimens. 

Where delays for correct identification are expected, 

the following preserving methods can be used: 

• Hard-bodied insects can be killed and preserved 

in 70% alcohol or methylated spirits. Never use 

water. 

• Butterflies and moths should be killed by 

freezing for 24 hours or by placing them in an 

airtight glass container with a ball of cottonwool 

or tissue, soaked in nail polish remover or 

acetone. After killing, place them gently in 

another container between layers of tissues. 

• Larvae should be killed with water at just below 

boiling point to ensure that they do not turn 

black and become difficult to identify. The 

specimens should then be transferred into 70% 

alcohol for preservation. 

• Soil-dwelling animals can be placed in moist soil 

with the container topped up with a little bit of 

padding (e.g. tissue) to minimise damage by 

shaking. 

Sending samples 

Where possible, samples should be sent via express 

post. Where it is suspected that samples may be 

delayed over a weekend before being sent or 

arriving at their destination, it is better to store them 

in a fridge, between 2-5 °C, to send the following 

monday. 

Photos 

It is possible to identify species from photos, 

providing a good macro lens is attached to 

your camera. It is recommended that multiple 

invertebrate photos are taken, together with photos 

of the damage they are causing. Good quality 

digital photos can be e-mailed to a departmental 

entomologist or consultant for identification. 

SECTION 6 MONITORING, RECORD KEEPING, SAMPLING TECHNIQUES AND ECONOMIC THRESHOLDS

Economic thresholds 

Economic thresholds are one of the cornerstones 

of IPM. They help to rationalise the use of 

pesticides and are one of the keys to 

profitable pest management. 

Example: A farmer estimates his cost of control (C) is 

$14 per hectare, and the on-farm value (V) of his canola is 

$390 per tonne ($0.39/kg). If the given loss (L) of each 

caterpillar found in every 10 sweeps is 6 kg/ha, then: 

The development of economic thresholds 

requires knowledge of pests, their damage, 

and the crop’s response to damage. 

Yield-based thresholds 

Yield-based economic thresholds are based on 

measured losses from invertebrate feeding damage that 

has a direct impact on yield. 

Quantitative measures of insect density are used to 

assess the pest status of different pests within a given 

crop type. The economic injury level (EIL) is defined 

as the pest density at which the loss caused by the pest 

equals in value the cost of the available control measures. 

This can also be expressed as the lowest population 

density that can cause economic damage. 

The economic threshold level (ET) or action threshold 

is a density level at which control measures are instigated 

to prevent the pest population from attaining the EIL. 

The formula for calculating the EIL includes the cost of 

control (chemical plus application costs), market value of 

the crop, yield loss attributed to a unit number of pest 

invertebrates and effectiveness of control measures. 

EIL = C/VLR 

Where 

C = cost of control 

(e.g. $/ha) 

V = value per unit of product 

(e.g. $/kg) 

L = yield loss per unit number 

of insects 

(e.g. kg of crop eaten 

by n insects) 

R = proportionate reduction of 

insect populations from 

control measure 

EIL = 14 ÷ (0.39 x 6) = 5.98 grubs/10 sweeps 

The lack of entomological broadacre research in the 

southern grain belt has seen many ETs become outdated 

and somewhat irrelevant to current economic costs and 

management practices. They will be updated in future. 

Quality-based or preventative 

thresholds 

A preventative pest threshold is a pest population that is 

lower than the pest population inflicting critical damage 

in a crop. In this context, critical damage occurs when a 

certain quality standard (such as percentage damaged 

seeds) is breached, resulting in a significant crop value 

discount. The threshold is set lower than the critical pest 

population because of the need to avoid this quality 

reduction - almost at all costs. 

When seed quality is the critical pricing factor, 

preventative thresholds, rather than a yield-based 

threshold, should be considered. 

This type of threshold is quite different from a yieldbased 

threshold where there is no hefty monetary 

penalty if the threshold is slightly exceeded. Because 

quality thresholds are usually very low, thorough 

monitoring for pests is essential. Inadequate sampling 

will very likely underestimate invertebrate numbers. 

Figure 6.1 Economic pest thresholds guiding control decisions 


9 



Example: In an average sized (1500 seeds/m 2 ) crop of 

edible soybeans, more than 2% of seeds are damaged 

when green vegetable bug populations exceed 0.5 adult 

bugs/m 2 . If bug populations exceed this critical level of 2% 

damaged seeds, the bonus for edible quality is lost and 

crop value can be downgraded by up to $400/ha (i.e. by 

many times the cost of control). Thus 0.5 green vegetable 

bugs/m 2 is a critical pest population in edible soybeans. 

The preventative or action threshold in soybeans is set at 

0.3 bugs/m 2 to ensure the critical damage level is not 

reached or exceeded. 

Crop size/yield is important to consider when using quality 

thresholds expressed as the maximum level of tolerable 

damage. This is because a given pest population inflicts 

more damage in percentage terms in a low yielding crop 

(i.e. one with fewer seeds per unit area) than the same 

population in a larger yielding crop with many more seeds 

per unit area. Therefore, small crops are at an inherently 

greater risk of being downgraded by pest damage. 

Consequently, it is desirable to have an estimate of the 

number of seeds per unit area (usually per square metre) 

when determining risk and thresholds for your crop. 

Defoliation thresholds 

Defoliation thresholds are a type of yield-based threshold, 

but are based on studies linking percent defoliation with 

yield loss. Studies have shown that vegetative crops are 

remarkably tolerant of attack and can tolerate up to 33% 

defoliation with no subsequent loss of yield. However, 

tolerable defoliation falls to 15-20% during flowering/ 

podding for most crops. 

Crop stage and health will ultimately have a large bearing 

on any decisions taken in these situations. The larger the 

crop, the less percentage defoliation occurs for a given 

number of leaf feeding pests. As such, rapidly growing, 

healthy crops are at lesser risk. Smaller, drought stressed 

crops not only face the risk of terminal damage, but 

are much more affected by sap-sucking pests, such as 

aphids and mites. Varying levels of defoliation are shown 

in Figure 6.2. 

10 

Nominal thresholds 


Where the damage factor is unknown, pests are often 

assigned nominal or fixed thresholds, based on the ‘gut 

feelings’ of experienced consultants and researchers. 

While many nominal thresholds have been proved to be 

reasonably close to the mark, they fall down in situations 

where crop values and spray costs vary widely. These 

types of thresholds should be used with caution. 

More factors to consider 

The presence of a pest does not imply it is causing 

economic damage to the crop. Monitoring over 

successive periods will provide a good indication of 

whether the pest population is increasing or deceasing 

over time. 

Other critical factors to be considered include insect and 

plant growth stages and the abundance of beneficial 

invertebrates. Late in the season, the loss of yield caused 

by driving a spray vehicle and wheel tracks through the 

crop to apply a treatment must also be considered. 

Multi-pest situations 

Where a number of pests causing similar damage are 

present, it is easier to express their combined damage 

potential in ‘standard pest equivalents’. This is much 

easier than having a separate threshold for each species 

and is the only workable solution where more than one 

species is present. Further consideration is needed if 

pest target species are of varying ages/developmental 

stages. 

Figure 6.2 Percent defoliation of soybean leaflets attacked by Helicoverpa larvae. 

Note how the measured defoliation seems to be less than suggested by the observer’s eye. 

Source: Brier et al 2009 (DEEDI)

Thresholds for immature caterpillars 

Since crop damage is often caused by the larval 

stages of a pest, the question is often asked 

about how to factor young larvae into thresholds 

and damage estimates. Where older larvae are 

detected at sub thresholds, the number of smaller 

larvae will have to be taken into account when 

assessing potential economic damage. 

Thresholds often assume that they will complete 

their development if not controlled, thus wreaking 

the maximum possible amount of damage. 

However, in practice many larvae are attacked by 

predators, killed by disease or even just forced off 

the crop (e.g. by rainfall or strong winds) before 

they reach a damaging size. For this reason, a 

decision can be made to hold off if the majority 

of caterpillars present are only small, particularly 

if large numbers of predators are present. In other 

situations, pests populations alone (irrespective 

of size) will be above threshold and determining 

the damage potential will be unnecessary. 

Control decision processes 

The ability to assess pest status and make valid control 

decisions or recommendations depends on the 

following factors: 

• the ability to identify invertebrate pests. 

Misidentification can lead to incorrect insecticide 

usage and continuing pest damage (e.g. mistakenly 

identifying Bryobia mites for redlegged earth mites); 

• confidence and the ability to find, and then accurately 

assess, pest population levels; 

• availability of an economic threshold and consideration 

of contributing factors (e.g. crop health and abundance 

of beneficial species); 

• understanding of pest behaviour and risk 

predictability. This is often shaped by an individual’s 

previous history and experiences of invertebrate 

pest problems. Fear of potential loss (especially at 

crop establishment), low confidence in the ability to 

detect pests and the inconvenience or time involved 

in monitoring are important practical considerations. 

The main impacts of pests in broadacre agriculture 

are through feeding damage to plants, transmission 

of diseases (particularly in high rainfall areas), reduced 

grain quality or appearance, and grain contamination. 

Changing market demands will alter the pest status of 

an insect. For example, acceptable levels of chewed seed 

damage in field peas will be much higher for feed-grade 

markets than those destined for human consumption. 

Market demands also determine the level of insect 

contamination that is acceptable in harvested grain 

samples before price penalties are applied. 

Putting it all together 

Important factors to consider before deciding 

to control pests 

• Accurate assessment of pest populations and 

their distribution within crops. For example, 

biased monitoring along a crop edge for weevils and 

armyworms may give a misleading result. Unbiased 

random observations across the whole paddock may 

indicate an average population that is below the EIL. 

Spot spraying could be an option in this case. 

• Physiological state of the crop. Is the crop healthy 

and growing well Poor crop-growth from moisture 

stress, poor finishing rains, disease pressure, lack of 

nutrients, waterlogging or wind/sandblasting will 

restrict the crop’s ability to cope with invertebrate 

pest pressures. 

• Prevalence of natural control agents such as 

parasitic wasps, ladybirds and insect diseases. Little 

information is currently available regarding 

the impact of beneficial invertebrates in 

suppressing pest populations in broadacre 

grains. However, it is known that large numbers 

of parasitoids and predators do reduce potential 

increases in pest populations and their presence 

should be taken into consideration, especially if pest 

numbers are approaching spray threshold levels. 

Feeding damage: no economic loss 

Feeding damage to the host plant can result in no 

economic loss to the final crop yield. This is because 

plants can recover from or out-compete the effects 

of the feeding injury. Economic feeding damage is 

the measurable loss to the crop yield or quality. 

For example, redlegged earth mites and lucerne 

flea are frequent seedling establishment pests that 

cause visually obvious injury to plants but may not 

result in measurable yield loss unless seedlings 

are severely stunted or actually killed. Even when 

a percentage of seedlings are killed, some plants 

such as canola can survive without a measurable 

yield loss if the remaining plants are able to express 

compensatory growth. 

Native budworm larvae can cause significant injury 

to the foliage of pre-flowering pulse crops without 

any measurable economic loss. However, a lesser 

number of larvae attacking the crop once the pods 

are formed will often result in measurable damage 

in the form of harvested grain weight losses. 


11 


• The dynamics of the pest population in relation 

to crop growth stage. The amount of crop damage 

which has already occurred must be considered 

against any additional damage which will occur if 

the crops are not sprayed. For example, earth mite 

numbers may have peaked and caused most of their 

damage during the cotyledon stage of a canola 

crop. If inspection occurs when the true leaves have 

formed, the most critical damaging stage will have 

passed and plants are likely to outgrow any further 

damage. 

• Growth stages of the invertebrate population. 

For many species, early lifestages consume very little 

or may even feed on other non-crop sources such as 

microflora. For example, caterpillar pests such as 

armyworms, cutworms and Helicoverpa species have 

multiple instars (life-stages), consuming only about 

14% of their total food requirement during the first 

four stages. Thus, the early stages cause relatively 

little feeding damage. Comparatively, the last two 

instars consume 86% of the total food requirement. 

Outcomes of pest control decisions 

No control – Insects below ET - or didn’t check. 


Apply insecticides when pest levels are below the 

EIL (‘insurance sprays’). This approach is common and 

somewhat understandable while insecticide prices are 

low, but it is ecologically unsustainable. This practice 

will increase the risk of insecticide resistance developing, 

reduce beneficial parasitoids and predator populations 

and thus increase the reliance on chemicals to control 

future pest incursions, resulting in higher chemical 

residues in crops, soils and waterways. 

Apply insecticides at the correct time. Well done! 

Insecticides applied too late. Plant damage is noticed 

too late due to a lack of appropriate monitoring. 

Significant yield losses can be expected despite 

insecticide application. 

12 


Table 6.2 Crop monitoring record sheet 

Sample Only 

Observer/recorder: 

Crop and variety: 

Paddock number/name: 

Paddock history (e.g. previous rotations, tillage): 

Sowing date: 

Chemical history (e.g. seed treatments, foliar insecticides, herbicides) 

Date:…………………Treatment:…………………………………… 



Observation 1 Observation 2 

Date:………………..Time:………...am/pm Date:…………..…..Time:…………..am/pm 

Crop growth stage 

Crop growing conditions (e.g. 

moisture stress) 

Weather conditions at time of 

sampling 

Sample number 1 2 3 4 5 Avg. 1 2 3 4 5 Avg. 

Pest 

Record no. per sampling unit (leaf/flowering spike/10 sweeps nets/other) 

Insect 

Life stage 

Damage (% of leaf area) 

Beneficials 

Insect 

Life stage 

Biosecurity Pests Record absence. If detect anything unusual call the exotic pest hotline 1800 084 881 

Insect 

Paddock Map 

high insect 

Paddock Map Paddock Map 

‘A’ pressure 

Other comments (e.g. weather 

history, soil moisture, herbicide) 

Decisions/action taken 


13 


Observer/recorder: 

Crop and variety: 

Paddock number/name: 

Paddock history (e.g. previous rotations, tillage): 

Sowing date: 

Chemical history (e.g. seed treatments, foliar insecticides, herbicides) 




Observation 3 Observation 4 

Date:………………..Time:………...am/pm Date:…………..…..Time:…………..am/pm 

Crop growth stage 

Crop growing conditions (e.g. 

moisture stress) 

Weather conditions at time of 

sampling 

Sample number 1 2 3 4 5 Avg. 1 2 3 4 5 Avg. 

Pest 

Record no. per sampling unit (leaf/flowering spike/10 sweeps nets/other) 

Insect 

Life stage 

Damage (% of leaf area) 


Beneficials 

Insect 

Life stage 

Biosecurity Pests Record absence. If detect anything unusual call the exotic pest hotline 1800 084 881 

Insect 

Paddock Map 

high insect 

Paddock Map Paddock Map 

‘A’ pressure 

Other comments (e.g. weather 

history, soil moisture, herbicide) 

Decisions/action taken 

14 


Table 6.3 Check-list of common broadacre pests in southern Australia 

Blue = Pests Green = Beneficials Red = Biosecurity threat 

A = adult L = larva 

Pre and/ 

or post 

emergence 

(winter) 

Cereals Pulse Canola Pastures 

& Lucerne 

Southern 

Ute Guide 

pp. 


Western 

Ute Guide 

pp. 

Mites 

RLEM, Bryobia, Balaustium, BOM 97-101 75-78 

Snails & slugs 

Numerous spp. 90-94 71-74 

Lucerne flea 

Sminthurus viridis 89 70 

True wireworm larvae (L) 

Numerous spp. 60 Not in WA 

Cockchafers (L) 

Blackheaded pasture cockchafer 

Accrossidius tasmaniae 

Redheaded pasture cockchafer 

Adoryphous coulonii 

61-63 Not in WA 

Yellowheaded cockchafer 

Sericesthis spp. 

WA Cockchafer 

Not in SE 

 

Australia 

46-47 


Heteronychus arator 64 78 

Grey false wireworm (L) 

Isopteron spp. 57 Not in WA 

Spinedtail weevil 

Steriphus caudatus 49 Not in WA 


Numerous spp. 135-136 111-112 

Carabid beetle (A,L) 

Numerous spp. 139 115 

Spiders 

Numerous spp. 134 108-110 

Aphids – bluegreen, pea, cow pea 

Acyrthosiphon spp., Aphis craccivora 

76-78 57-59 

Canola aphids – green peach, 

turnip, cabbage 

Myzus sp., Lipaphis sp., Brevicoryne sp. 

73-75 54-56 

Cereal aphids - corn oat 

Rhopalosiphum spp. 70-71 52-53 

Cutworms (L) 

Agrotis spp. 23-24 22-23 

Armyworms (some seasons) (L) 

Persectania spp., Leucania sp. 21-22 20-21 

Brown pasture looper (L) 

Ciampa arietaria 36 28 

Pasture day moth (L) 

Apina calisto 34 33 

Grass anthelid (L) 

Pterolocera sp. 45 Not in WA 

Pasture tunnel moth (L) 

Philobota productella 35 Not in WA 

Pasture webworm (L) 

Hednota sp.. 32-33 24-25 

15 


Table 6.3 Check-list of common broadacre pests in southern Australia (continued) 




& Lucerne 


Ute Guide 

pp. 

Western 

Ute Guide 

pp. 


Pre and/ 

or post 

emergence 

(winter) 

continued 

16 

Mandalotus weevils (A) 

Mandalotus spp. 52 Not in WA 


Listroderes difficilis 47 37 

Spotted vegetable weevil 

Steriphus diversipes 48 38 

Bronzed field beetle (L) 

Adelium brevicorne 56 43 

Vegetable beetle 

Gonocephalum spp. (L) (A) 59 45 

True wireworm larvae (L) 

Numerous spp. 60 Not in WA 

Small lucerne weevil (A) 

Atrichonotus sp. 


NSW, WA 

only 

White fringed weevil (L) 

Naupactus leucoloma 51 41 

Sitona weevil 

Sitona discoideus 50 40 

Locust 

Chortoicetes sp. 83-84 64-65 

Sandgroper 

Clindraustralia sp. 

Not in SE 

Australia 


Forficulina auricularia 88 69 


Nysius vinitor 65 49 


Numerous spp. 135-136 111-112 



Spiders 


Predators 

ladybirds, hover flies, lace wings, 

nabids 

132-133, 

137-141 

39 

68 

106-107, 

113-114, 

116, 

119-120 

Parasites 

aphid parasites, moth parasites 119-131 95-105 

Turnip moth (L) 

Agrotis segetum 

Russian wheat aphid 

Diuraphis noxia 171 138

Table 6.3 Check-list of common broadacre pests in southern Australia (continued) 




& Lucerne 


Ute Guide 

pp. 

Western 

Ute Guide 

pp. 

Spring 

BIO- 

SECURITY 

Mites 

RLEM, Bryobia, Balaustium, BOM 97-101 75-78 

Aphids – bluegreen, pea, cow pea 

Acyrthosiphon spp. 

Aphis craccivora 

76-78 57-59 

Canola aphids – green peach, 

turnip, cabbage 

Myzus sp., Lipaphis sp., Brevicoryne sp. 

73-75 54-56 

Cereal aphids – corn, oat 

Rhopalosiphum spp. 70-71 52-53 

Armyworms (L) 

Persectania spp., Leucania sp. 21-22 20-21 

Native budworm (L) 

Helicoverpa spp. 18-20 17-19 

Diamondback moth (L) 

Plutella xylostella 25-26 26-27 

Lucerne leafroller (L) 

Merophyas divulsana 29 31 

Lucerne seed web moth (L) 

Etiella behrii 27-28 30 

Pea weevil (A) 

Bruchus pisorum 55 44 

White fringed weevil (A) 

Naupactus leucoloma 51 41 

Locust 

Chortoicetes sp. 83-84 64-65 


Nysius vinitor 65 49 


Numerous spp. 135-136 111-112 



Spiders 


Predators 

ladybirds, hover flies, lace wings, 

nabids 

132-133, 

137-141 


106-107, 

113-114, 

116, 

119-120 

Parasites 

aphid parasites, moth parasites 119-131 95-105 

Russian wheat aphid 

171 138 

Diuraphis noxia 

 

Sunn Pest 

Eurygaster integriceps 181-182 148-149 

Hessian fly 

Mayetiola destructor 169-170 136-137 

Leaf miners 

Agromyzidae: Diptera 180 146 

Barley stem gall midge 

Mayetiola nordei 175 142 

17 


Table 6.4 Check-list of common pests in southern Australia by crop type* 


Barley 

18 

Main Risk 

Period 


• • • 

Armyworms 

• • 

Australian plague locust • • • 


• • 


(SE Australia only) 

Blue oat mite 

• • 

• • 

Bryobia mite 

• 

Corn aphid 

• 

Corn earworms (SE Australia only) • 

Cutworms 

• • • 

Earwigs • • 

Grasshoppers • • • 

Grass anthelid (SE Australia only) • 

Leafhoppers 

• 

Lucerne flea 

• • 

Mandalotus weevil (SE Australia only) • 


• 

Oat aphid 

• 

Pasture tunnel moth (SE Australia only) • 


• 

Polyphrades weevil (SE Australia only) • 


• • 


• • 

Slugs 

• • 

Snails (pointed or conical) • • • 

Spinetailed weevil (SE Australia only) • 

Spotted vegetable weevil • 

True wireworms (SE Australia only) • 

Vegetable beetle (larvae) • 

Yellowheaded cockchafer • • 

Legend 

• Emergence (autumn – early winter) 

• Vegetative (winter) 

• Flowering (spring) 

• Harvest (contaminant) 

Wheat 


Main Risk 

Period 


• • • 

Armyworms 

• • 

Australian plague locust • • • 


• • 



Blue oat mite 

• • 

• • 

Bryobia mite • • 

Corn aphid 

• 


Cutworms 

• • • 




Leafhoppers 

• 

Lucerne flea 

• • 



• 

Oat aphid 

• 

Pasture tunnel moth (SE Australia only) • 


• 



• • 


• • 

Slugs 

• • 







* This check-list is a guide only. Pest occurrence and timing may vary between crops, regions, and seasons, influenced by seasonal climatic conditions, 

soil type and land management programs.

Table 6.4 Check-list of common pests in southern Australia by crop type* (continued) 

Oats 

Main Risk 

Period 


• • • 

Armyworms 

• • • 

Australian plague locust • • 


• • 



Blue oat mite 

• • 

• • 

Bryobia mite 

• 

Corn aphid 

• 


Cutworms 

• • • 

Earwigs 

• 



Leafhoppers 

• 

Lucerne flea 

• • 



• 

Oat aphid 

• 



• • 

Slugs 

• • 






Legend 





Lentils 


soil type and land management programs. 


Main Risk 

Period 



• • 

Bllue green aphid 

• 

Blue oat mite 

• • 


• 

Bryobia mite 

• 


Cowpea aphid 

• 

Cutworms 

• • • 

Earwigs 

• 

Grasshoppers • • 


• 

Lucerne flea 

• • 

Lucerne seed web moth 

• 



• 

Onion maggot 

• 


• • 


• • 

Slugs 

• • 


Thrips • • 



• • 

19 




Lupins 



20 

Main Risk 

Period 



• • • 


• 

Blue oat mite 

• • 


• 

Bryobia mite 

• 


Cowpea aphid 

• 

Cutworms 

• • • 

Earwigs 

• 



• 

Lucerne flea 

• • 


• 



• 

Onion maggot 

• 


• • 


• • 

Slugs 

• • 




• • 

Weed web moth 

• 

Legend 





Peas 


Main Risk 

Period 



• • 


• 

Blue oat mite 

• • 


• • 

Bryobia mite 

• 


Cowpea aphid 

• 

Cutworms 

• • • 



Lucerne flea 

• 


• 



• 

Onion maggot 

• 

Pea aphid 

• 

Pea weevil 

• 


• • 

Slugs 

• • 



• •


Canola 

Main Risk 

Period 



• • 

Blue oat mite 

• • 

Bronzed field beetle • • 


• 

Bryobia mite 

• 

Cabbage aphid 

• 

Cabbage centre grub 

• 

Cabbage white butterfly • • 

Cockchafers (WA species only) • • 


Cutworms 

• • • 


• 



• 

Grey false wireworm (SA only) • 

Lucerne flea 

• • 


Millipedes • • 


• 


• 


• • 


• 

Slugs 

• • 

Small lucerne weevil (WA and NSW only) • 




Turnip aphid 

• 

Vegetable beetle (adults) • • 


• • 

Weed web moth 

• 

Legend 





Pastures and Lucerne 


Main Risk 

Period 


• • • 



• • • 



• • 

Blue oat mite 

• • 


• 

Bryobia mite • • 

Cowpea aphid 

• 

Cutworms 

• • • 

Earwigs 

• • • 

Grass anthelid 

• • 


Leafhoppers 

• • 

Lucerne flea 

• • • 

Lucerne leafroller 

• • • 


• 


• 


• • 

Pasture tunnel moth (SE Australia only) • • 


• • 

Pea aphid • • 

Redheaded pasture cockchafer • • 


• • • 


• 

Sitona weevil 

• 

Slugs 

• • 

Small lucerne weevil (WA and NSW only) • • 


Spotted alfalfa aphid • • 

Thrips 

• • 

Weed web moth 

• 

White-fringed weevil 

• • • 




21 


Biosecurity 

7 

Biosecurity

SECTION 7 

Biosecurity 

Introduction 

Biosecurity is about the protection of livelihoods, 

lifestyles and the natural environment that could be 

harmed by the introduction of new pests (insects, mites, 

snails, diseases and weeds). Biosecurity is a national 

priority implemented off-shore, at the border and onfarm. 

Biosecurity is essential for your business. 

Australia’s geographic isolation has meant that we have 

relatively few of the pests that affect plant industries 

overseas. Freedom from these exotic pests (those that 

are not present in Australia) is a vital part of the future 

profitability and sustainability of Australia’s plant 

industries. Biosecurity allows us to preserve existing 

trade opportunities and provide evidence to support 

new market negotiations. 

Farm biosecurity is a set of management practices and 

activities that are implemented on-farm to protect a 

property from the entry and spread of unwanted pests. 

Farm biosecurity is essential for your business and is 

your responsibility as well as that of every person visiting 

or working on your property. 

Growers can play a key role in protecting themselves 

and the Australian grains industry from exotic pests by 

implementing farm biosecurity. If a new pest becomes 

established on your farm, it will affect your business 

through: 

• increased farm costs (e.g. changing crop rotations, 

additional chemical control and implementing other 

management treatments and strategies); 

• reduced productivity (reduced yield and/or quality); 

• loss of markets. 

For more information on securing your farm, refer to the 

Farm Biosecurity Manual for the Grains Industry. 

High priority exotic pest threats to the 

grains industry 

A number of pests present in other countries but not in 

Australia (exotic pests) have been identified as potential 

threats to the grains industry at the national level. Some 

of the medium to high risk ‘in crop’ exotic pest threats 

have been included in this I SPY resource manual. 

Serious consequences would be expected should any of 

these pests enter and become established in Australia. 

In addition to the exotic pests listed here, a number of 

biosecurity pest threats are listed in Crop Insects: The Ute 

Guide booklet, SA (pp. 168-182)/WA (pp. 135-149) and a 

complete list of the exotic pest threats can be found in 

the Grains Industry Biosecurity Plan. 

Early detection and immediate reporting 

increases the chance of effective and 

efficient eradication. 

What do you need to do 

New pests will occasionally enter and establish in 

your crop. Conducting regular surveillance and crop 

monitoring is a core part of your farm management 

practices and gives you the best chance of spotting a 

pest soon after it arrives. The earlier you detect a new 

pest, the better the chances of eradication. 

To effectively detect something new: 

• know the normal pests associated with your crops - 

so you notice anything unusual; 

• investigate all crops that are not performing or are 

showing pest symptoms – get them checked out if 

you are not sure of the cause; 

• record all surveillance activities. 

Surveillance at the farm level contributes essential 

information to regional biosecurity efforts and ultimately 

to the national status (presence/absence) of a pest. 

SECTION 7 Biosecurity 

1 


If you see anything unusual, 

call the Exotic Plant Pest Hotline 

1800 084 881 Speak to your department 

of primary industries before 

sending any samples. 


Calls to the Exotic Plant Pest Hotline are forwarded to 

an experienced person in the department of primary 

industries in each state or territory. Every report will be 

investigated and treated confidentially. 

If you suspect that you have found an exotic plant pest 

the following general precautions should be taken: 

• mark the location of the pest detection and limit 

access to the area; 

• do not allow people, stock and equipment near the 

affected area; 

• wash hands, clothes and boots that have been in 

contact with affected plant material or soil; 

• do not touch, move or transport affected plant 

material without advice from your state department 

of primary industries. 

2 

Biosecurity vehicle check list 

SECTION 7 Biosecurity 

It is essential that the 

correct sampling protocol 

is followed including 

packaging, handling and 

transport to the laboratory 

assigned for diagnosis. 

Incorrect handling could 

spread the pest further or 

render the samples unfit for 

identification. 


For copies of the Grains Industry Biosecurity Plan and 

the Farm Biosecurity Manual for the Grains Industry, 

as well as information on key exotic pests of the 

grains industry, visit the Plant Health Australia website 

(www.planthealthaustralia.com.au/biosecurity/ 

grains) or contact biosecurity@phau.com.au, or your 

state’s Grains Biosecurity officer. 

Carry a biosecurity tool kit in your vehicle. Each tool kit should contain cleaning items for clothing, vehicles 

and equipment in addition to personal safety gear. 

A basic vehicle biosecurity kit should include: 

• Stiff brushes and a scraper for cleaning tyres 

and shoes. 

• Dustpan and brush for cleaning inside vehicle 

cabins. 

• Personal safety gear such as rubber boots, rubber 

gloves, disposable overalls and boot covers. 

• Footbath and bucket for disinfecting boots 

and equipment. 

• Approved disinfectant for cleaning down 

vehicles/equipment. 

• Hand sanitiser, soap and a minimum of 5 litres 

of water. 

• A small hand sprayer with a solution of 

methylated spirits (at the rate of 70% 

methylated spirits to 30% water). 

• Flagging tape to mark sample location. 

• Strong plastic and paper bags for collecting 

samples and sealing items for disposal. 

Additional items for an advanced biosecurity kit: 

• Camera. 

• GPS to record sample collection location. 

• Sample jars and plastic boxes for sample 

collection.

Glossary 

8 

Glossary

SECTION 8 

Glossary 

Abdomen: the third and rear (posterior) major division 

of an insect’s body. 

Adfrontal area/suture: refers to an area on the head 

of lepidopteran larvae. The adfrontal suture is formed by 

the fusion of adfrontal sclerites. 

Aestivation: summer dormancy. An invertebrate (i.e. 

snails) may be metabolically or physically inactive during 

summer or periods of high temperatures. 

Alate: winged form of some insects, such as aphids or 

ants, that have both winged and wingless forms. 

Antennae: a pair of appendages used for sensing, 

attached to the head. 

Anterior: front; in front of. 

Biological control: is the reduction of pest 

populations by natural enemies (predators, parasites and 

pathogens). This may involve intervention by people for 

conservation or release of natural enemies that feed on 

or attack pests. 

Bt: Bacillus thuringiensis, a bacterium that is used 

as an insecticide against many insects, particularly 

lepidopteran larvae. 

Campodeiform: a term used to describe the shape 

of a larva. Campodeiform larvae are generally elongated 

with a tapering body and well-developed legs (e.g. 

ladybird larvae). 

Cauda: a tail-like process at the tip of the abdomen. 

Shape, size and hair patterns are characteristic for certain 

species. 

Aperture: opening. In the context of this manual, this 

refers to the opening in a snail’s shell where its body 

comes out. 

Apical meristem: growing tip of a plant (root and 

shoot). 

Apodous: legless. 

Arthropods: members of the Phylum Arthropoda. 

This includes insects and their allied forms, such as 

spiders and mites. 

Asexual: means ‘without sex’ and in the context of this 

manual refers to invertebrates that reproduce without 

exchanging genetic material between two parents. 

Beneficial insect: an insect that helps to suppress 

pest populations. 

Bifurcate: a structure that is divided or forked into two 

arms. 

Biocontrol agents, biological agents: natural 

enemies (predators, parasites and pathogens) that feed 

on or attack pests. 

Cephalothorax: fused head and thorax (Arachnida). 

Cerci: a pair of appendages at the end of the abdomen. 

Cervical shield: refers to a hardened body part 

(sclerite) just behind the head (prothorax) of lepidopteran 

larvae. 

Chelicerae: the pointed mouth parts of mites and other 

arachnids. Anterior pair of appendages in arachnids. 

Chlorotic marking: pattern of damage usually 

caused by insects with piercing and sucking mouthparts 

(as well as some plant diseases) where parts of the plant 

leaves/stems lack green colour (chlorophyll) and have a 

‘bleached’ appearance. 

Clypeus: anterior sclerite on an insect’s head below the 

face and above the labrum. 

Complete metamorphosis: a development 

process in which the immature insect bears no visual 

resemblance to, and acts differently from, the adult 

form. Insects develop in four stages within this lifecycle: 

egg; larvae; pupae; adult. 

SECTION 8 GLOSSARY 

1 



Cornicles: see siphuncle. 

Cotyledon: a seed leaf; leaf of the embryo of a seed 

plant. 

Crochets: hooks situated at the base of prolegs. In this 

manual it refers to the ‘soles of the feet’ of caterpillar rear 

legs (abdominal legs). 

Cultural control: Non-insecticidal tactics to prevent or 

reduce pest populations. These can include crop rotation, 

trap cropping, crop hygiene, removal and destruction 

of weeds and diseased plants, planting/harvest dates, 

site selection, cultivar and variety selection, nutrient 

management and the incorporation of nectar producing 

plants to encourage natural enemies. 

Diapause: a ‘resting stage’. A state of reduced 

metabolic and physical activity which is not directly 

caused by unfavourable environmental conditions (cf. 

aestivation). For example, redlegged earth mites eggs 

diapause over summer in southern parts of Australia. 

Dorsal: top or uppermost. 

Dorsoventral: in a line from the upper to the lower 

surface. 

Elytra: hardened forewing covers present on insects in 

some orders, but seen mostly in beetles (Coleoptera). 

Eruciform: a term used to describe the shape of a 

larva. Eruciform larvae have a cyclindrical, elongated 

body and short legs. 

Exoskeleton: hard, outer plate coverings on the body. 

This is characteristic of arthropods. 

Exotic pest: a pest that is present in another country 

but not in Australia or a pest that is native to another 

country and has been introduced to Australia. 

Filamentous: slender or thread-like. Generally refers 

to the form of antennae. 

Filiform: slender or thread-like. Generally refers to the 

form of antennae. 

Frass: insect excreta, faeces. 

Furcula: forked tail-like organ used for jumping or 

springing in springtails (Collembola), usually folded 

underneath the abdomen. Lucerne fleas have a furcula. 

Generalist predators: are mainly free-living 

predators that consume a large number and range of 

prey during their life. 

2 


Green bridge: describes the role of weeds and 

volunteer crop plants in helping some pests to survive 

from one cropping season to the next. 

Halteres: rudimentary hindwings (Diptera) used for 

balance. 

Haustellum: part of the proboscis (mouthpart) that is 

adapted as a sucking organ. 

Hemelytra: half leathery/half membranous forewing 

of hemipterans. 

Honeydew: a sticky substance that is secreted by 

some aphids and scale insects. It is sugar-rich and can be 

used as a form of reward for predatory arthropods that 

then protect the herbivores. 

Hypocotyl: the stem part of a germinating seedling 

which bears the cotyledons. 

Incomplete metamorphosis: development 

process in which an immature insect hatches from an 

egg (or is born live in some insects) and gradually turns 

into an adult through a series of moults. 

Insecticide resistance: Resistance occurs when 

application of insecticides removes susceptible insects 

from a population leaving only individuals that are 

resistant. Mating between these resistant individuals 

gradually increases the proportion of resistance in the 

pest population as a whole. Eventually this can render 

an insecticide ineffective, leading to control failures in 

the field. 

Instar: a stage of growth in an insect’s lifecycle between 

each moult (between the egg and adult stages). 

Insurance sprays: applying insecticides when pest 

levels are below the economic injury level for the crop. 

This practice is ecologically unsustainable and will 

increase the risk of insecticide resistance developing 

and reduce populations of beneficial parasitoids and 

predators. 

Invertebrates: animals without backbones. 

IPM: integrated pest management. A control strategy 

where a range of biological, chemical and cultural 

control practices are combined to manage and prevent 

pests from reaching damaging levels in agriculture. 

Keel: ridge or raised section, as in the ‘keel of a boat’. 

In the context of this manual, this refers to the ridge 

present on the upper body of some slug species.

Labium: lower lip. 

Labrum: upper lip. 

Larva (plural larvae): the juvenile form of 

invertebrates that undergo complete metamorphosis. 

Mandibles and maxilla: hardened jaw structures for 

chewing plant material or crushing prey. 

Mandibulate: mouthparts, chewing mouthparts. 

Mantle: a structure on snails/slugs which covers part 

of the body. 

Maxillary and labial palp: segmented sensory 

extensions. 

Mesoseries: the arrangement of crochets of a larval 

proleg in a band (single, inner or longitudinal). 

Mesothorax: middle (2 nd ) of the three thoracic 

segments. 

Metamorphosis: physical change in the form of an 

animal during its development. 

Metathorax: posterior (3 rd ) of the three thoracic 

segments. 

Monoculture: the cultivation of a single type of crop 

over a wide area. 

Moult: when an invertebrate sheds its outer layer 

(exoskeleton) revealing new growth, and passes from 

one nymphal stage (instar) to another (incomplete and 

complete metamorphosis). 

Mummies: common term for the swollen bodies of 

parasitised aphids. 

Natural enemies: an insect that helps to suppress 

pest populations (cf. beneficial insect). 

Nectar: a sugar-rich liquid produced either by the 

flowers of plants or by extra-floral nectaries. It is useful 

for attracting pollinating animals. 

Nymph: an immature stage (following hatching) of an 

insect that undergoes incomplete metamorphosis. 

Ocelli: the ‘simple’ eyes of an insect or other arthropod. 

Omnivore: used to describe an organism that feeds on 

both plant and animal substances. 

Ovipositor: egg-laying organ, usually protruding from 

the tip of the abdomen. 

Palps: specialised appendages near the mouth that 

are used for sensing in a similar way to antennae. 

Panicle: a loose, irregularly branched, flower cluster. 

Parasite: an organism that lives in or on the body of 

another organism during some portion of its lifecycle. 

Parasitoid: an arthropod that parasitises and kills its 

host. A parasitoid is parasitic in its immature stages and 

free-living as an adult. 

PestFax/PestFacts: free services designed to keep 

growers and advisors informed about pest related issues 

and solutions in southern grains regions of Australia. 

Electronic newsletters are distributed and aim to help 

growers by providing timely information about pest 

outbreaks, effective control and current information 

about relevant and new research findings. 

Pheromones: highly specific odours that function 

as chemical signals, often as a sex attractant between 

individuals of the same species. These are often used in 

traps to attract specific insects. 

Phytophagous: plant feeding. 

Pleuron: the lateral region of any segment (generally 

thoracic or abdominal) of an arthropod’s body. 

Polyphagous: feeds on multiple food types. 

Proboscis: extended beak-like mouthpart. 

Process: a natural projection from a part of an organism. 

In the context of this manual it refers to insects with 

projections, such as cauda on aphids. 

Proleg: a non-segmented appendage used for 

grasping. Abdominal prolegs can be found on moth 

and butterfly larvae as well as some sawfly larvae. Anal 

prolegs can also be present on the abdomen. 

Pronotum points: the dorsal hardened body section 

(sclerite) of the prothorax pleuron in true wireworms. 

Prophylactic: preventative or protective. 

Prothorax: anterior (1 st ) of the three thoracic segments. 

Protoconch: the embryonic (or earliest) part of a snail 

shell. 


3 



Pupa (plural pupae): transition stage in the lifecycle 

where larval characters are lost and adult features 

develop (complete metamorphosis). 

Radula: rasping mouthpart of molluscs. 

Raster: a group of bare areas, hairs (setae) and spines 

on the ventral surface of the last abdominal segment of 

scarabaeoid larvae. 

Refuge area: a place providing protection or shelter. 

In the context of this manual, this refers to an area 

providing protection from insecticide sprays and/or 

providing suitable habitat for beneficial species. 

Residential: permanently living within the system. 

Rostrum: the protruding, piercing and sucking 

mouthparts of all bugs; particularly used to describe a 

weevil’s snout. 

Scarabaeiform: refers to the shape of a larva. 

Scarabaeiform larvae have a ‘C’-shaped body, with 

relatively short legs and a swollen lower abdomen. 

Sclerite: a hardened plate on the body wall bounded 

by structures or membranous areas. 

Sclerotised: hardened. 

Scutellum: a small shield-like sclerite. 

Selective pesticide: a pesticide that kills only target 

pests and has minimal impact on non-target organisms, 

particularly beneficial invertebrates. Sometimes referred 

to as a ‘soft’ pesticide. 

Setae: bristles or hairs. 

Siphuncles: paired tubular wax-secreting structures 

(projections) on the rear of an aphid’s abdomen. 

Spinnerets: an apparatus from which silk is spun. 

Spiracles: small openings in the body that allow 

oxygen exchange (breathing holes). 

Sporulation: the production of spores (fungi). 

Striations: a longitudinal ridge or furrow. 

Stylet: one of the mouthparts modified for piercing; 

generally a long, thin, rigid appendage. 

Suture: a seam or line of contact between two sclerites 

that makes the sclerites connected and immovable. 

4 


Tarsus (pl. tarsi): insect foot. 

Taxonomy: is the branch of science that sorts all 

living things into groups based on their similarity or 

relatedness. 

Tegmina: hardened, leathery forewings of some 

insects. 

Tentacle: a flexible organ of touch (e.g. ‘feeler’ of snails/ 

slugs). 

Thorax: the middle section of an adult insect’s three 

main body divisions. Legs and wings are attached to the 

thorax. 

Transient: mobile species that do not permanently 

reside in a system and generally have shorter generation 

times compared with residential species. 

Trochanter: the second segment of an insect leg. 

Tubercle: small bumps/humps on the forehead of 

invertebrates. 

Umbilicus: is the hollow space on the underside of a 

snail’s shell, around which the shell coils. Not all snails 

have an umbilicus. 

Vector: an organism, in this context an invertebrate, 

that transmits disease to another organism (e.g. aphids 

can be a vector of barley yellow dwarf virus in cereals). 

Ventral: front, underneath. 

Wing venation: the pattern of veins on an insect’s 

wing.

References 

The information in this document was derived in 

part, from the following sources: 

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identification and control. CSIRO Publishing, Melbourne. 

Blackman, R.L. and Eastop, V.F. (2000) Aphids on the 

worlds crops, an identification and information guide, 

second edition. Wiley, New York. 

Brier, H., Charleston, K., McLennan, A., Hughes, J. 

and Dougall, A. (2009). Pulse break crop IPM reference 

manual. Queensland AgriSciences, Department of 

Employment Economic Development and Innovation, 

Mackay. 

Child, J. (1965). Australian spiders. Periwinkle Press, 

Gladesville. 

CSIRO, Department of Entomology (1991). The insects of 

Australia: a text book for students and research workers, 

second edition. Melbourne University Press, Melbourne. 

Emery, R., Mangano, P. and Michael, P. (Eds) (2005). 

Crop insects: the ute guide, western grain belt edition, 

Department of Agriculture Western Australia and Grains 

Research and Development Corporation, Canberra. 

Glatz, R. (2009). SARDI Entomology: Guide to the insects on 

the northern Adelaide Plains. South Australian Research 

and Development Institute (SARDI), Adelaide. 

Goodyer, G. (1978). The identification of armyworm, 

cutworm, budworm and looper caterpillar pests. 

AGbulletin2. Department of Agriculture, New South 

Wales, Sydney. 

Goodyer, G. Identifying major noctuid caterpillar pests. 

NSW Agriculture Rhône-Poulenc Rural Australia Pty Ltd, 

New South Wales, Baulkham Hills. 

Gordh, G. and Headrick, D.H. (2001). A dictionary of 

entomology. CABI Publishing, Cambridge. 

Gullan P.J. and Cranston P.S. (2000). The insects: an 

outline of entomology, second edition. Blackwell Science, 

Melbourne. 

Henry, K., Bellati, J., Umina, P. and Wurst, M. (Eds) (2008). 

Crop insects: the ute guide, southern grain belt edition. 

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Horne, P. and Page, J. (2008). Integrated pest management 

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Kono, T. and Papp C.S. (1977). Handbook of agricultural 

pests. State of California Food and Agriculture, Division 

of Plant Industry, California. 

Leonard, E., Baker, G.H. and Hopkins, D. C. (2003). Bash 

’em, burn ‘em, bait ‘em: integrated snail management 

in crops and pastures. South Australian Research and 

Development Institute, Adelaide. 

Mangano P. (2008) Insect training course manual 

broadacre crops and pastures. Department of Agriculture 

and Food, Perth. 

Mascord, R. (1980). Spiders of Australia: a field guide. 

Reed New Holland, Sydney. 

Matthews, E.G. (1987). A guide to the genera of beetles 

of South Australia, Part 2. South Australian Museum, 

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McCaffery, D., Potter, T., Marcroft, S. and Pritchard, F. (Eds) 

(2009). Canola best practice management guide for southeastern 

Australia. Grains Research and Development 

Corporation, Canberra. 

Peterson, A. (1960). Larvae of insects: an introduction to 

nearctic species. Ohio State University, Ohio. 

Smith, B.J. Non-marine molluscs: A key to the families of 

non-marine molluscs of quarantine concern in Australia. 

Lucid Key, AQIS. 

Smith, B.J and Kershaw, R.C. (1979). Field guide to the nonmarine 

molluscs of south-eastern Australia. Australian 

National University Press, Canberra. 

Umina, P.A., Fitt, G.P., Anderson, C.A. and Webb, L.E., (Eds) 

(2008). Special issue: invertebrate pests of grain crops and 

integrated management: current practice and prospects 

for the future. Australian Journal of Experimental 

Agriculture, vol. 48, issue 12, pp. 1481-1607. 

Zborowski, P. and Storey, R. (2003). A field guide to insects 

in Australia, second edition. Reed New Holland, Sydney. 


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