Progressive Crop Consultant July/August 2019


July/August 2019

Mitigating Pesticides and

Sediment in Tail Water using Polyacrylamide (PAM)

Do Liquid Digestates, By-Products of Bioenergy

Production, have Nematode-Suppressive Potential?

Management Practices to Improve

Soil Function

Neofabraea Leaf and Twig Lesions, a New

Disease of Super-High-Density Olive Trees


Volume 4 : Issue 4


September 26th | 1:00PM - 9:00PM

September 27th | 7:00AM - 1:00PM

July /August 2019

For more information

and the full agenda

see pages 31-35 1





powered by:


You’re Invited

PCA Hours:

CCA Hours:



September 26th-27th

Visalia Convention Center

303 E. Acequia Ave. Visalia, CA 93291

Workshops and Seminars

Mixer & Networking

Meals Included

(Breakfast, Lunch and Snacks)

Full Gala Dinner

Live Entertainment

(Jason Bird, Magician and Illusionist)

Industry Exhibits


ONLY $100

per person

The Crop Consultant Conference takes place

September 26th | 1:00PM - 9:00PM

September 27th | 7:00AM - 1:00PM

This 2-day conference provides Education and Networking opportunities for PCAs, CCAs, and Ag Retailers from

across California. Join us for our Opening Reception and Gala Dinner, the first night, followed by our seminars and

Industry Lunch the next day. Attendees will learn about current issues impacting California’s agriculture industry, the latest

technologies, and more at our workshops and seminars while earning 7.5 PCA & 9.0 CCA CE Credits.

powered by:

2 VALUED Progressive OVER Crop Consultant $1000


July /August 2019


By Pre-Registering TODAY!










Mitigating Pesticides

and Sediment in

Tail Water using

Polyacrylamide (PAM)

Selective Forces That

Act on Weeds and

How They can Alter

Plant Populations and


Do Liquid Digestates,

By-Products of

Bioenergy Production,

have Nematode-

Suppressive Potential?

Management Practices

to Improve Soil Function

Iron Deficiency in

Fruit and Nut Crops in


Magnesium Deficiency

in Grapes

Neofabraea Leaf and

Twig Lesions, a New

Disease of Super-High-

Density Olive Trees




PUBLISHER: Jason Scott


EDITOR: Kathy Coatney




Phone: 559.352.4456

Fax: 559.472.3113




Abdelhossein Adelati

Department of Agricultural

and Biological Engineering,

UC Davis

Michael Cahn

UC Cooperative Extension

Monterey County

David Chambers

UC Cooperative Extension

Monterey County

Caroline Eberlein

Department of Nematology,

UC Riverside, Parlier, California

Matthew Fidelibus

Extension Specialist,

Department of Viticulture and

Enology, UC Davis

Phoebe Gordon

Area Orchard Systems Advisor,

Merced County

Sarah Light

Agronomy Advisor, Sutter,

Yuba, and Colusa Counties

Kevin Day

County Director and

UCCE Pomology Farm

Advisor, Tulare/Kings County

Steven T. Koike,

Director, TriCal Diagnostics

Zhixuan Qin

UC Cooperative Extension

Montery County

Lynn Sosnoskie

UCCE Agronomy and Weed

Science Advisor, Merced

and Madera Counties

Florent Trouillas

Cooperative Extension

Assistant Specialist in Plant

Pathology, University of


Andreas Westphal

Department of Nematology,

UC Riverside, Parlier,


Mohammad Yaghmour

Area Orchard Systems

Advisor, Kern County

Ruihong Zhang

Department of Agricultural

and Biological Engineering,

UC Davis



Emily J. Symmes

UCCE IPM Advisor,

Sacramento Valley

Kris Tollerup

UCCE Integrated Pest

Management Advisor,

Parlier, CA

The articles, research, industry updates, company profiles, and

advertisements in this publication are the professional opinions

of writers and advertisers. Progressive Crop Consultant does

not assume any responsibility for the opinions given in the


July /August 2019


Mitigating Pesticides and

Sediment in Tail Water using

Polyacrylamide (PAM)

BY MICHAEL CAHN | UC Cooperative Extension Monterey County

ZHIXUAN QIN | UC Cooperative Extension Monterey County

DAVID CHAMBERS | UC Cooperative Extension Monterey County

4 Progressive Crop Consultant July /August 2019


were annually treated with PAM in the

Sprinkler and flood irrigation

often generate runoff that

transports sediment from agricultural

fields to downstream rivers,

lakes, and estuaries. Additionally,

some classes of pesticides, such as

pyrethroids, bind to the suspended

sediments in tail water which can cause

toxicity to aquatic organisms in these

receiving waters. Currently numerous

rivers and creeks in California are

considered impaired by pesticides and

sediment transported with drainage

from agricultural land. As water quality

regulations become stricter, growers will

need to implement practices on their

farms that treat potential pollutants in


Tail water can be a particularly

challenging water quality problem on

the central coast of California where

overhead sprinklers are widely used

for vegetable production. Sprinklers

can contribute to high concentrations

of suspended sediment in tail water

because the force of the falling water

droplets erode soil aggregates and

allow fine particles to be carried with

runoff water. Research that we have

conducted on the central coast has

shown that adding a low concentration

of polyacrylamide to irrigation water

can dramatically reduce sediment

loads and sediment-bound pesticides

in agricultural tail water (Figure 1,

see page 6). Across a range of soil

types, polyacrylamide treatment

reduced sediment concentration in

runoff by more than 90 percent on

average. On some highly erosive soils

polyacrylamide reduced sediment

concentration in sprinkler induced

runoff by more than 98 percent.

Total phosphorus and nitrogen

concentrations in sprinkler runoff were

also reduced by 40 percent to 70 percent

using polyacrylamide.

Despite dramatic improvements in

water quality, polyacrylamide, also

called PAM, has been slow to be

adopted as a management practice

on the central coast and in much

of California. One reason may be

because of misunderstandings about

how to most effectively use PAM for

treating runoff, especially for sprinkler

irrigation. Another reason is that several

physical properties of polyacrylamide

make it challenging for handling and

applying to fields.

Continued on Page 6


By 1999, almost 1 million acres of land

northwest of the United States.


4 hours post-application 72 hours post-application


Effective Organic Weed Control

SUPPRESS® Herbicide EC is a broad spectrum contact

herbicide for post-emergent, non-selective weed control.

• Proven efficacy

SUPPRESS® Herbicide EC provides

fast and effective burndown

• No pre-harvest interval

• Excellent tool in IPM

• Helps break chemical resistance

• Non-volatile, emulsifiable concentrate



(800) 876-2767


July /August 2019


Continued from Page 5

Brief background on PAM

Polyacrylamide is a simple polymer molecule made of

carbon, nitrogen, and oxygen. Various forms of PAM exist,

but the type used to stabilize soil and prevent erosion is

a very large, mostly negatively charged molecule (12-15

megagrams per mole). Agricultural PAM is commercially

available in dry powder (granular), emulsified liquid, and

dry tablet forms, and costs as little as $4 to $6 per pound of

active ingredient depending on the formulation, supplier,

and cost of the raw materials used for manufacturing PAM

(i.e. natural gas). PAM is used for many nonagricultural

purposes such as a flocculant for waste and potable water

treatment, processing and washing of fruits and vegetables,

clarification of juices, and paper production. It is also a

component of makeup.

Use of PAM for Irrigation

and Erosion Control

Because PAM is a very long, linear molecule it easily binds

to soil aggregates, thereby preventing soil erosion during

irrigation events. Beginning in the early 1990’s numerous

studies demonstrated that low application rates of PAM (1

to 2 lb/acre) reduced runoff and improved water quality

in furrow systems by stabilizing the aggregate structure of

soil, improving infiltration, and flocculating out suspended

sediments from irrigation tail water. Most of the research

and demonstrations of PAM were conducted in furrow

system on very erodible soils in Idaho and Washington

states.. By 1999, almost 1 million acres of land were

annually treated with PAM in the northwest of the United

States. Additionally, growers in the San Joaquin Valley and

the Bakersfield areas of California used PAM to reduce soil

erosion under furrow and flood irrigation.

6 Progressive Crop Consultant July /August 2019

All photos courtesy of M. Cahn.

Figure 1: Runoff from overhead sprinkler water untreated (left). Treated with 5 ppm PAM (right).

Working with PAM

PAM can be very difficult to use

if it is not handled correctly. Wet

PAM is very slippery, and because

it solubilizes slowly in water,

PAM spills should be cleaned up

with a dry absorbent rather than

washing it with water. Although

it is not toxic to humans, some

precautions should be taken when

handling PAM: Use gloves to

avoid irritation to skin. Goggles

will prevent eye exposure. Also, a

dust mask is recommended when

pouring or handling granular or

powder forms of PAM to avoid


One rule of thumb to keep in

mind is that it is much easier to

add water to PAM than to add

PAM to water. Dry PAM rapidly

absorbs water, increasing its

original volume many times to

become a slimy, gooey substance. Dissolving dry PAM

in water can be challenging. Because PAM is a very large

molecule it does not dissolve readily into water and requires

many hours of agitation to dissolve. It will often stick to

the side of a tank when being mixed. Also, mixing up

concentrations greater than 0.15 percent in water is nearly

impossible because the solution becomes very viscous and

difficult to agitate. Some manufacturers sell effervescent

PAM tablets which aids dissolution in water, but still only

relatively dilute solutions can be mixed up.

For these reasons it easiest to use liquid PAM products

that have been emulsified with a carrier such as mineral

oil or humectants, or work with dry PAM products,

such as granular PAM or PAM in a tablet form. The

emulsified liquid products generally have active ingredient

concentrations ranging from 25 to 50 percent.

Application Methods

For applications in furrow systems dry or liquid product

can be added to water flowing in a head ditch or main line

(if gated pipe is used) at a rate to achieve a 2.5 to 10 ppm

(parts per million) concentration. Automated equipment

can be used to spoon feed granular PAM into flowing

canal water. The application can be made continuously

during the irrigation or until the water advances almost to

the end of the furrows. An alternate application method,

called the “patch method” involves spreading granular

PAM to the first 3 to 5 feet of each furrow. The granular

PAM slowly dissolves as water flows down the furrows. A

similar strategy is to add a PAM tablet at the beginning of

each furrow. Applications into sprinkler systems require

specialized equipment for injecting either liquid PAM or

dry PAM into pressurized pipe which will be discussed in

more detail later.

Environmental and Food Safety

Only PAM products labeled for application to food crops

should be used in agriculture. Also, the buyer/processor/

Federal Environmental Protection

Agency (EPA) requires that PAM sold

for agricultural uses contain less than

0.05 percent acrylamide monomer. In

soil, PAM degrades rapidly by physical,

chemical, biological, and photochemical

processes, but it does not decompose

into the acrylamide monomer. A

previous study of the movement of PAM

from agricultural fields showed that

less than three percent of the applied

product remained in the runoff leaving

the field. The remaining PAM in the tail

water was almost completely removed

through adsorption to suspended

sediments as the water flowed a distance

of 300 to 1000 ft. in the tail water ditch.

Figure 2: Trailer outfitted for injecting liquid PAM into the main line of an irrigation

system using an auger metering pump.

shipper of the produce should be

informed that PAM is being applied to

the crop, especially if the application is

made near harvest.

Agricultural PAM used for soil erosion

is not toxic to mammals. Environmental

studies of anionic (negatively charged)

PAM have not shown any detriment

to fish, algae, and aquatic invertebrates

such as Ceriodaphnia dubia, and

Hyalella azteca. Polyacrylamide is

sometimes confused with acrylamide

monomer, a precursor in the

manufacturing of PAM. Acrylamide

monomer, a potent neurotoxin, has a

high, acute toxicity in mammals. The

Vestaron’s new bioinsecticide for fruits,

vegetables and high-value field crops,

Spear ® -Lep targets immature

Lepidopteran pests such as loopers,

worms, and caterpillars. It’s novel

mode of action offers a new

tool for insect resistant

management programs.


©2019 Vestaron Corporation. All Rights Reserved.

Always Read and Follow Label Directions.

4717 Campus Drive, Kalamazoo, Michigan 49008


One concern with using emulsified

liquid PAM is that the mineral oil

carrier can have toxicity to downstream

aquatic invertebrates. However, toxicity

from the mineral oil can be avoided by

using PAM formulations with either

high concentrations of PAM (>50

percent active ingredient) or with nonoil

carriers such as humectants.

Optimizing PAM

for Sprinklers

Although many research studies have

evaluated the efficacy of PAM in furrow

systems, fewer studies have evaluated

the use of PAM with sprinklers.

Applications of PAM made before

irrigating with sprinklers, such as by

spraying PAM solution or broadcasting

dry product on the surface of the soil

were far less effective than continuously

injecting PAM at a low rate into the

irrigation water. Injecting PAM only at

the beginning of an irrigation was also

less effective in controlling sediment in

runoff than a continuous application at

a low concentration during the entire

irrigation. Our studies on the central

coast showed that injecting PAM to

achieve a 5 ppm concentration in the

irrigation water provided the highest

reduction in sediment, nutrients, and

pesticides in the tail water using the

least amount of product. In some fields

2.5 ppm PAM provided equal efficacy

for control of suspended sediments as 5

ppm PAM. Treatment with PAM should

be started with the first irrigation

after planting and continue during the

following two to three irrigations. PAM

should be reapplied when sprinkler

irrigating after the field has been

cultivated. Product can be saved in

Continued on Page 8

July /August 2019


Figure 3: Prototype dry PAM applicator for pressurized irrigation systems (left) and PAM cartridge that inserts into the applicator (right).

Continued from Page 7

fields where very little runoff occurs during the first few

hours of an irrigation by making an initial application for

the first half hour and then applying product again when

runoff becomes significant.

Injecting PAM into Pressurized

Irrigation Systems

The chemical characteristics of PAM that make it so

effective as a flocculant, also make it difficult to inject into

pressurized irrigation systems. Liquid PAM solutions are

viscous and will clog chemigation equipment with valves

such as diaphragm and piston pumps, as well as venturi

injectors. Also, because the desired PAM concentration in

the irrigation water is low, injection rates as low as one to

three ounces per minute are needed to treat 10 to 15-acre

fields. Most small, gas-powered centrifugal pumps usually

cannot be easily calibrated to inject at these low rates.

Peristaltic pumps can be adjusted to inject slowly but often

are not designed to operate under high pressures that are

common in sprinkler main lines. The best type of pump

that we have identified for injecting liquid PAM is an auger

pump (Figure 2, see page 6) which has no valves and can

inject viscous solutions at very low rates. These pumps also

maintain a consistent injection rate at pressures as high as

100 psi (pounds per square inch).

Although liquid formulations of PAM are the best option

for pressurized irrigation systems, we are currently

exploring methods of injecting dry PAM into pressurized

sprinkler systems. The advantage of dry PAM is that it is

generally cheaper than liquid products and the possibility

of introducing toxicity from the inactive emulsifying

ingredients in the liquid products is eliminated. Another

advantage of this approach is that it may require less labor

since no pump must be calibrated and managed during

an irrigation. The dry PAM applicator is loaded with

cartridges containing either granular or tablet forms of

PAM (Figure 3). A portion of the water from the main

line is diverted through the applicator chambers and then

added back to the main water stream. Although the PAM

concentration is lower than can be achieved with liquid

PAM, preliminary tests have shown that as much as 90

percent of the suspended sediments can be eliminated in

the runoff (Figure 4, see page 10). Further studies during

the upcoming season will evaluate the practicality of use

this applicator in commercial fields.

Other Potential Benefits of PAM

In addition to water quality benefits, we have observed or

measured agronomic benefits from the use of PAM. Because

PAM stabilizes soil aggregates, soil is less likely to crust

under the impact of sprinkler droplets, which improves

infiltration and decreases the volume of runoff. In one field

trial, PAM reduced runoff from four successive sprinkler

irrigations from 4000 gallons per acre to less than 1500

gallons per acre. Less crusting of the soil may also improve

germination of small seeded vegetables such as lettuce. In

one of four replicated field trials conducted in commercial

lettuce fields, we were able to measure an increase in yield

and plant weight with the use of PAM. This yield increase

may have been a result of better penetration of water or

because the seed emerged earlier than in the non-treated

plots. Although we have not conducted long-term studies,

anecdotal reports from growers who applied PAM to their

fields over successive years were that soil structure was

improved by keeping the fine particles in place.

Continued on Page 10

8 Progressive Crop Consultant July /August 2019

Worms, Thrips, Leafminers


Only Radiant ® insecticide controls worms, thrips and leafminers. And

university trials in Arizona and California show that Radiant outperforms other

commonly-used vegetable insecticides on all three of these pests. As a member

of the spinosyn class of chemistry (IRAC Group 5), Radiant controls pests like no

other class of chemistry used in vegetables. The Re-Entry Interval is only 4 hours,

and the Pre-Harvest Interval is 1 day for most crops.

July /August 2019

Visit us at


Trademark of Dow AgroSciences, DuPont or Pioneer and their affiliated companies or

respective owners. Always read and follow label directions.


Figure 4: Samples of field runoff from irrigation water treated using the dry PAM applicator (left) and untreated (right).

Continued from Page 8

An additional benefit of PAM is the

savings associated with less frequent

cleaning out of sediment that clogs

ditches and fills retention ponds during

the irrigation season. Often once or

twice per year growers on the east

side of the Salinas valley who farm

on soils prone to crusting and runoff

must schedule a backhoe and crew to

remove sediment from ditches and

ponds and redistribute the material in

their fields. To reduce costs with using

PAM, growers also can receive costshare

payments under the United States

Department of Agriculture (USDA)

Natural Resources Conservation

Service (NRCS) Environmental Quality

Incentive Program) (EQIP).

In summary here are a few key concepts

on using PAM for controlling sediment

in runoff:

• Polyacrylamide is a long linear

molecule that binds to soil and can

flocculate suspended sediments in


• PAM does not readily solubilize in

water and increases the viscosity of

water (thickens).

• Concentrations of 2.5 to 5 ppm

PAM in irrigation water are ideal for

optimizing erosion control benefits

under sprinkler and furrow irrigation.

• For agricultural purposes only use

anionic PAM products for erosion

control and labeled for use on food


• Small amounts of granular PAM can

be applied to the beginning of furrows

before flood irrigating (1 to 3 lbs/acre).

• For sprinklers PAM needs to be

injected into the irrigation water during

the entire irrigation event.

• Applying PAM to the soil before

sprinkle irrigating or only at the

beginning of an irrigation will not

maximize control of sediment in runoff.

• PAM should be applied during the

first three to four irrigations after

planting or transplanting and when

irrigating after soil cultivation.

• Auger pumps are ideal for metering

liquid PAM products into pressurized

sprinkler water.

• PAM itself is not toxic, but the mineral

oil in some liquid PAM products can be

toxic to aquatic organisms.

• A prototype applicator is being

developed to inject dry PAM into

pressurized sprinkler systems, although

it is not yet commercially available.

Further information on using

polyacrylamide is available on the UC

Cooperative Extension Website for

Monterey County (http://cemonterey.


Comments about this article? We want

to hear from you. Feel free to email us at

10 Progressive Crop Consultant July /August 2019


100% Water Soluble 80%+ Amino Acids Immediate Availability

Pure Protein Dry


Fish Protein Hydrolysate

Effective for all crops _ conventional and organic

• Calculate application rates in lbs

of PPD/acre/season vs. Units of


• 1lb PPD = 5 Gallons Liquid Fish

• 1lb PPD = 5-8lbs Soy Protein

• Save on freight by not shipping water

• Nitrogen derived from

Fish Protein, will not leach

Apply as a foliar spray or through irrigation •

Will not clog emitters, micro sprinklers •

Compatible with other nutrient •

and pest control products

Apply with Compost Teas •

Use with Pure Kelp Dry 0-0-20 •


To see our PPD Based blends • 7.5-1-25 • 5-7-14 • 11-8-8 - insecticides & herbicide products

July /August 2019





and How They Can Alter Plant Populations and Communities

Figure 1. All photos courtesy of Lynn Sosnoskie.

BY LYNN SOSNOSKIE | UCCE Agronomy and Weed Science Advisor, Merced and Madera Counties

Weeds are problematic in

crops, primarily because

they compete with commodities

for water, light, and nutrients,

which can result in yield loss.

Weeds can also impact crops, indirectly,

by serving as alternate hosts for insects

and pathogens (Del Pozo-Valdivia 2019;

Petit et al. 2011), providing habitat for

vertebrate pests (White et al. 1998),

or by impeding harvest operations

(Morgan et al. 2001; Smith et al. 2000),

among many other effects.

Resistant Weeds

Consequently, growers employ a

variety of control strategies, including

the application of herbicides, to

manage unwanted vegetation in

their production systems. Although

herbicides can be extremely effective,

weeds may escape chemical control

for a variety of reasons, including

the evolution of herbicide resistance.

Currently, there are 500 confirmed cases

(species x site of action) of herbicide

resistance, worldwide (Heap 2019).

With respect to the United States, 164

unique instances of resistance have

been documented. Most resistances (52

cases) are to the acetolactate synthase

(ALS) inhibitors followed by the

photosystem II (PS II) inhibitors (26

cases), 5-enol-pyruvyl-shikimate-3-

phosphate synthase (EPSPS) inhibitors

(17 cases), and the acetyl-CoA

carboxylase (ACCase) inhibitors (15

cases) (Heap 2019). Examples of active

ingredients for these sites of action

would be rimsulfuron (ALS-inhibitor),

atrazine (PS II-inhibitor, glyphosate

12 Progressive Crop Consultant July /August 2019

(EPSPS-inhibitor), and sethoxydim

(ACCase-inhibitor), respectively.

Herbicide Resistance

Herbicide resistance is an evolutionary

process. Herbicides do not directly

cause the mutations that lead to

herbicide resistance, rather their

repeated use over space and time

‘selects’ for the genetic mutations that

result in reduced herbicide efficacy. In

short, the genetic mutations that confer

herbicide resistance are already present

before the herbicide is applied. The

herbicide treatment eliminates all the

weeds that do not contain the mutated

gene (i.e. the susceptible plants); if no

further intervention is undertaken,

the resistant survivors will continue to

grow, flower, and set seed, which will be

added to the soil seedbank. Over time,

the resistant trait becomes dominant

in the population as susceptible

individuals die out without successfully

reproducing (Figure 1) (Hanson et al.


Adaptations to Weed Control

Herbicides are not, however, the only

selective forces that can alter the

structure of weed populations and

communities. Any weed management

or crop production practice can select

for weed species that are adapted

to the resulting environment. For

example, repeated and consistent

mowing (Pirchio et al. 2018) can favor

the development of species that are

naturally prostrate or spreading in habit,

like clovers (Trifolium spp.) (Figure 2,

see page 14). The use of drip-irrigation

in processing tomatoes can lower the

numbers of annual weeds that emerge

and compete with the crop (likely due to

reduced surface wetting that stimulates

germination) while facilitating the

establishment of field bindweed

(Convolvulus arvensis), a deep-rooted

and drought-tolerant perennial weed

(Shrestha et al. 2007; Sosnoskie and

Hanson 2015; Sutton et al. 2006).

The adoption of reduced tillage in

processing tomatoes favors the spread of

field bindweed which can be suppressed

by frequent soil disturbance. Even

hand-weeding can serve as a selective

pressure; Echinochloa crus-galli subsp.

Oryzicola, a form of barnyardgrass

that mimics cultivated rice both in

physical form and phenology, is difficult

to visually identify and may escape

removal in labor-intensive production

systems (McElroy 2014).

Managing Herbicide Resistance

When it comes to managing herbicide

resistance, the Weed Science Society of

America (WSSA) has a list of strategies

to employ in order to increase the

diversity of tools in a production

system. However, these tools have value

beyond the prevention and mitigation

of resistance; varying the types and

timing of disturbances should help to

combat difficult to control species that

arose in response to the repeated use

of a weed control strategy. Some of the

best management practices endorsed by

the WSSA include:

Continued on Page 14


At HELM, our values have a tradition of trust and partnership.

Blending your demands with our innovations, we create crop protection with

greater ‘grower’ value for optimized production, performance and profits.

HELM. Delivering Solutions that Cultivate Growth.


July /August 2019

Always read and follow label directions. HELM® is a trademark of HELM AG. ©2019 HELM Agro US, Inc.


Using multiple herbicide modes of action and applying

herbicides at the proper rates and times

Adopting mechanical weed control when appropriate

Rotating crops to diversify the type and timing of weed

control and production practices

Emphasizing cultural practices that are suppressive to


Bring the

heat on


weeds and

insects with

Distributed by

Figure 2: Herbicide resistance is an evolutionary process. Herbicides do not actively mutate the target weeds, rather, the repeated

use of an active ingredient over space and time eliminates susceptible individuals (plain green patches) from a population leaving

only the resistant plants (orange patches with the “R”) to reproduce and set seed. Over time, the resistant trait becomes dominant in

the population as susceptible individuals die out without successfully reproducing.

Continued from Page 12

P.O. Box 2106 • Turlock, CA 95381


Spreader-Activator with Citrus Extract

R-Agent DL ® dramatically

boosts performance.

Use R-Agent DL with and without oil

on agricultural, turf, ornamental, and

non-cropland sites.

Chemurgic Agricultural Chemicals, Inc.

• Adjuvants

• Nutrients

• Organics

• Formulation


14 Progressive Crop Consultant July /August 2019


100% Active


For more information:


Tom Kelm: 559 696-6558

Preventing the movement of weeds within and between


Reducing weed seed production and seed return to the soil


Understanding the biology and ecology of troublesome

species and identifying the forces that could allow them to

become dominant in a given production environment

Comments about this article? We want to hear from you. Feel

free to email us at


Del Pozo-Valdivia (2019) Weeds serving as alternative hosts for diamondback


Last accessed on May 14, 2019.

Hanson et al. (2013) Selection pressure, shifting populations, and herbicide

resistance and tolerance. ANR Publication 8493. https://anrcatalog.ucanr.

edu/pdf/8493.pdf. Last accessed on May 16, 2019.

Heap (2019) The International Survey of Herbicide Resistant Weeds. http:// Last accessed on May 14, 2019.

McElroy (2014) Vavilovian mimicry: Nikolai Vavilov and his little-known

impact on weed science. Weed Sci. 62:207-216.

Morgan et al. (2001) Competitive impact of Palmer amaranth (Amaranthus

palmeri) in cotton (Gossypium hirsutum). Weed Tech 15:408-412.

Petit et al. (2011) Weeds in agricultural landscapes. A review. Agron. Sustain.

Develop. 31:309-317.

Pirchio et al. (2018). Autonomous mower vs. rotary mower: effects on turf

quality and weed control in tall fescue lawn. Agronomy 8:15.

Shrestha et al. (2007) Sub-surface drip irrigation as a weed management

tool for conventional and conservation tillage tomato (Lycopersicum esculentum

Mill.) production in semi-arid agroecosystems. J. Sustain. Agric. 31:91–112.

Smith et al. (2000) Palmer amaranth (Amaranthus palmeri) impacts on yield,

harvesting, and ginning in dryland cotton (Gossypium hirsutum). Weed

Technol. 14:122-126.

Sosnoskie and Hanson. (2015) Field bindweed (Convolvulus arvensis) control in

early and late-planted processing tomatoes. Weed Technol. 30:708-716.

Sutton et al. (2006) Weed control, yield and quality of processing tomato

production under different irrigation, tillage and herbicide systems. Weed

Technol. 20:831–838.

White et al. (1998) The control of rodent damage in Australian macadamia

orchards by manipulation of adjacent non-crop habitats. Crop Protect.



Navel Orangeworm Monitoring Systems

for conventional and organic tree nuts


Optimum detection/navel orangeworm ipm


Male Attractant System:



Delta Trap

Female Attractant System:



Egg Trap

NEW! Predator Detection System:


NEW! Multi-Gender

Attractant System:


NOW L 2 High

Pheromone Lure

• Male NOW Attractant High/Low-

Release Pheromone Lures

NOW L 2 Low

Pheromone Lure

• Female NOW – Oviposition

– Attractant, Concentrated,

Stabilized lures

• Detect mite predators, such as the

Six-spotted thrips and Stethorus beetles

• Based on the Great Lakes IPM trap

• Used in recent university trials

• May be used as a treatment threshold


• Contains easy hanger

Note: Apply miticides based on UC-IPM Guidelines


• Male/Female NOW Attractant,

High-Release PPO-K

Microporous Gel Peelable

Kairomone Lure

More information below

• Male/Female NOW Attractant,

High-Release PPO-K Microporous

Gel Peelable Kairomone Lure

• Duplicates • Ready-to-Use, USDA release rate

peelable backing

standard vial at 100 mgs per day

• 12 weeks field longevity

• Easy to use; ready-to-use

barrier pack

NEW! NEW! Multi-Gender Attractant System: PHEROCON® ® PPO NOW PPO-K Lure


Precision - multicomponent

release •

Higher capture rates •

Controls the release of

more volatile molecules

while allowing release

of less volatile molecules.

• Volatile molecules

• Less volatile


Earlier detection •

• Greater longevity

Contact your local supplier and order now!

Visit our website: or call: 1- 866-785-1313.

© 2019, Trécé Inc., Adair, OK USA • TRECE, PHEROCON and CIDETRAK are registered trademarks of Trécé, Inc., Adair, OK USA • TRE-1383, 5/19

*Patent pending

July /August 2019





Your Edge – And Ours – Is Knowledge.

All photos courtesy of Caroline Eberlein.

Do Liquid Digestates, By-Products

of Bioenergy Production, have

Nematode-Suppressive Potential?

BY CAROLINE EBERLEIN | Department of Nematology, UC Riverside, Parlier, California

RUIHONG ZHANG | Department of Agricultural and Biological Engineering, UC Davis

ABDELHOSSEIN ADELATI | Department of Agricultural and Biological Engineering, UC Davis

ANDREAS WESTPHAL | Department of Nematology, UC Riverside, Parlier, California

Experimental tank wagon for band application of liquid digestate in a walnut orchard. The digestate is

pumped via a custom nozzle underneath the tree row. Food hygiene guidelines need to be observed.

Large amounts of organic wastes

of food or animal origin accrue in

cropping systems and in the food

industry. Traditionally, many of these

byproducts could remain in the agricultural

production chain. For example,

almond hulls may be used as dairy feed.

Others ended up in landfills. With the

continually increasing amounts, and for

other market changes, alternative uses

are urgently needed. When converting

these energy-rich materials to biogas,

organic matter from food waste or

animal manure are processed through

anaerobic digestion by microorganisms

in specialized biodigesters. The resulting

biogas is then used as fuel for electricity

and heat generation or put into cars and

other vehicles as transportation fuel.

The anaerobic digestion process has

been favored to reduce the emissions of

methane and other gases from organic

waste materials during natural decomposition.

Although animal manure is

probably the most widely used substrate

for anaerobic digestion worldwide, food

waste is another organic substrate due

to its high methane production potential.

Besides biogas, a liquid effluent

called anaerobic digestate is also

produced from digestion processes. The

disposal of such residues represents an

environmental and economic challenge.

A meaningful use of this material

would favorably impact environmental

stewardship by reducing waste disposal

issues, and could benefit agriculture by

recycling the nutrients in the digestate

for plant growth benefits.

Plant-parasitic Nematodes

Plant-parasitic nematodes are a

constraint in crop production, especially

in perennial crops in California. Long

cropping cycles, soils that favor high

nematode densities, and favorable

climate conditions, increase nematode

reproduction. In the past, nematodeinfested

fields have been effectively

treated with soil fumigants before

planting or with various post-plant

nematicides. The use of fumigants and

non-fumigant nematicides is challenged

by human and environmental health

concerns. For example, regulation

limits the use of 1,3-dichloropropene

materials under so-called township

cap. The quantity that may be used

per year is restricted per 36 square

miles (=Township). Clearly, more

environmentally friendly alternatives to

the use of these chemicals are urgently


Environmentally Friendly


A number of studies have investigated

the potential of these digestates as

bio-fertilizers. Because these wastes

originate from plant material they

are nutrient rich and their use fits

into a cyclic production of returning

byproducts to the primary field

production. Such cycling has positive

environmental effects. In some studies,

the potential of these digestate for

managing pests and diseases in different

crops were explored. In a study in

Germany, anaerobically digested

maize silage suppressed the sugar beet

cyst nematode, a major pest of sugar

beet production in Central Europe.

Using organic materials as nematode

management tool is challenging because

such materials can vary greatly in

their physico-chemical composition.

This composition likely will impact

the nematode-suppressive potential

of digestates. It probably depends not

only on the substrate but also on the

conditions during anaerobic digestion.

In a project supported by the

Department of Pesticide Regulation

(DPR), digestates from different sources

of different processing conditions

and substrate base as well as varying

chemical constitution showed

differences in nematode suppressive

potential. This illustrated the challenge

of working with organic materials,

Continued on Page 18

16 Progressive Crop Consultant July /August 2019

Experiment with pepper in microplots. Microplots are contained areas of two foot diameter and five feet long

culvers perpendicularly inserted in the ground, and filled with test soils. Each of these plots allow for precise

application amounts of digestates or other treatments.

July /August 2019


Watermelon experiment for testing for efficacy of digestates to suppress nematode population densities. Watermelon

seeds are grown in root-knot nematode-infested soil after at-plant application of digestates for one month. Then roots

are harvested and examined for nematode-induced galling.

Continued from Page 16

and the need to quickly and easily

characterize the nematode suppressive

potential of digestate. For this purpose,

a robust fast turn-around bioassay was

tested in three different incubation

environments, two different growing

containers, and with two different

nematode life stages as inoculum. In

this test, a single radish seed is planted

into nematode-infested soil in small

containers after a small amount of

digestate has been added. After four to

five days, a staining procedure is used

to visualize the nematode that have

penetrated the young radish roots. Low

Radish seedling four days after seeding into nematode-infested

soil and digestate amendment. This seedling has sufficient roots to

allow for examination of nematode infection.

numbers compared to roots that did

not receive the digestate suggest some

suppression of nematode infection. In

this project, results were similar in the

different contexts, and the digestate

tested was able to suppress nematodes

in all contexts. Based on these results,

this bioassay may be useful as a quality

control tool for measuring nematode

suppressivenesss of organic liquids

that could possibly be implemented by

commercial laboratories.


Temperature is one of the most

significant parameters influencing

anaerobic digestion. Biogas generation

through the anaerobic digestion

process can

take place over

a wide range of


from as low as

50 F (10 °C) to

135 F (55 °C),


to psychrophilic

104 F (>40°C

) conditions.

Because of

an increased

biogas yield,

in most cases,

digesters are

operated under

mesophilic or thermophilic conditions.

Temperature does influence the activity

and composition of microorganism

groups. This influences the methane

yield and likely the constitution of the

resulting digestate possibly influencing

the nematode suppressive potential. Of

course the substrate, which can vary

between different organic wastes will

impact this constitution as well. The

substrate and the process may therefore

impact what secondary metabolites

are produced during digestion,

and thus nematode suppressive

potential. Therefore, liquid manure

and food waste both processed either

mesophilically or thermophilically were

used in a number of experiments to

study the influence of these two factors.

Food Waste Versus Manure

In the radish bioassay with the sugar

beet cyst nematode, no difference in

root penetration was found between

the two substrates (food waste vs

manure) but a significant difference was

found between the two processes. The

thermophilic digestates were able to

reduce nematode root penetration by

more than 50 percent compared to the

mesophilic digestates. In greenhouse

experiments, the digestates of different

substrates and processes were used

to treat watermelon in soil infested

with Meloidogyne incognita (root-knot

nematode, RKN) to test the versatility

of nematode suppression. After fiveweeks

incubation, plants were harvested

and roots evaluated for nematode

damage (root galling, and number of

18 Progressive Crop Consultant July /August 2019


In greenhouse experiments, the digestates

of different substrates and processes

were used to treat watermelon in soil

infested with Meloidogyne incognita

(root-knot nematode, RKN) to test the

versatility of nematode suppression.


egg masses). Nematode-induced galling

was similar or higher in plants from

the digestate treatments than for plants

from the control. A numerically small

but significant reduction in root galling

was found in food waste compared to

manure. None of the digestates resulted

in better plant growth when compared to

the control.

Small Field Experiments

Microplot and small field experiments

were conducted to implement the

findings of controlled conditions into

practical field contexts. Application

strategies included drench application

of the digestates as pre- or post-planting

treatments. In a bell pepper microplot

trial in RKN-infested soil, five different

digestates were applied at planting. Three

months later, plants were harvested and

roots assessed for nematode suppression.

The digestates did not result in improved

plant growth compared to the control

treatments. Nematode damage in roots

was not reduced after treatment with

digestates. Although, populations for

RKN after harvest, were lower in plots

treated with mesophilic manure and

similar to the nematicide control. Similar

studies were conducted with almond and

walnut and ring nematode, root-knot and

root lesion nematodes but results were

somewhat variable indicating the need

for improved application strategies.

In summary, some beneficial effects of

thermophilic digestates were observed on

plant growth and nematode suppression

Continued on Page 20

0-Hour REI

0-Day PHI





• Fast, high efficacy results

• Powdery mildew, botrytis, rust

– knockdown & curative

• Mites, controls all life stages

and eggs

• Scale, mealy bug, aphid

and more

• Safe on beneficial predators

• Multi-site activity – no known


• Tank mix compatible with sulfur

• Excellent crop safety


July /August 2019


Root-knot nematodes are known for their root changing effects. Galls or the name-giving knots are visible on young seedlings,

and older plants. Water and nutrient uptake are impeded by such unusual roots.

Continued from Page 19

compared to mesophilic digestates

under controlled conditions. In

preliminary tests in the greenhouse,

nematode suppression was observed

but under field conditions with different

nematode pests of different crops,

inconsistent results were obtained.

Further experimentation is needed

to elucidate the chemical nature of

compounds conferring nematode

suppression, and how to make use of

this beneficial capacity of the waste

product digestate. The environmental

and economic benefits of cycling

plant nutrients and concomitantly

suppressing soil pests make this a

valuable endeavor.

Comments about this article? We want

to hear from you. Feel free to email us at

20 Progressive Crop Consultant July /August 2019


Strength where

it counts

When it comes to protecting high-value crops like strawberries, choose a product with multiple benefits.

KENJA ® 400SC fungicide from Summit Agro USA is a Group 7 fungicide that has been

carefully designed to offer PCAs and their growers outstanding control of Botrytis (Gray mold), a key

disease in strawberries, as well as broad spectrum activity on Powdery Mildew and Anthracnose.

KENJA is also one of the most active products in its class of chemistry.

Maximize shelf life.

Already proven to provide in-season disease control, a harvest day application of KENJA continues to

provide disease protection. And KENJA holds a 0-day PHI in strawberries, so it can increase

marketable shelf life for strawberries, all while providing application and harvest flexibility.

When applied at 15.5 oz. as the last spray

before harvest, KENJA can help add days

to post-harvest strawberry shelf-life.


Minimize resistance potential.

The SDHI molecular flexibility and unique molecular

structure of KENJA give it one of the lowest potentials

for fungicide resistance, furthering its excellent

disease control year to year.

KENJA ® 400SC fungicide

• Attack Botrytis

• Maximize marketable yields

• Increase sellable shelf life


KENJA® 400SC Fungicide is sold exclusively through

Helena Agri-Enterprises and Tenkoz member companies.

• Minimize SDHI fungicide

resistance potential

KENJA is an invention and registered trademark of Ishihara Sangyo Kaisha, Ltd., and is

manufactured and developed by ISK Bioscience Corporation. ©2019 Summit Agro USA LLC.

July /August 2019


Management Practices to Improve

Soil Function

BY SARAH LIGHT | Agronomy Advisor, Sutter, Yuba, and Colusa Counties

Soils are essential for life on

earth. In addition to the fundamental

role of soil in agriculture,

soils support building and recreation,

filter and store water, recycle nutrients,

protect our communities from flooding,

sequester carbon, and due to the wide

microbial diversity of soils, have even

been a source of antibiotic and prescription

drug discovery. Soils are alive!

In fact, up to one billion bacterial and

several yards of fungal hyphae can live

in a single gram of soil. These microbes,

invisible the naked eye, are at the core of

many of our soil building management


Despite being one of our most

important natural resources, we

may not often think about soil as

something that needs to be built or

protected. Unfortunately, soils globally

and in the United States are being

destroyed at a rapid rate. Soil is a nonrenewable

resource and once a soil

has been degraded to the point where

it cannot be used to produce crops, it

Photo courtesy of Jeff Mitchell.

Figure 1: Farmers and consultants examining crop

residue and root growth and development in strip till

corn in Chowchilla, California.

is very challenging, if not impossible,

to restore. As President Franklin

Delano Roosevelt once said, “the

nation that destroys its soil, destroys

itself.” The United States Department

of Agriculture (USDA)/National

Resources Conservation Service

(NRCS) estimates that the annual cost

of soil erosion in the United States alone

is $44 billion. While we cannot re-create

soil once it is destroyed, we can employ

on farm management practices to

reduce the risk of soil destruction and

to increase soil function.

The main principles of soil health are

to maintain soil cover, minimize soil

disturbance, keep a living root in the

soil, and incorporate plant diversity.

These principles are intended to keep

soils alive by encouraging flourishing

soil microbial communities and

physically protecting soils from either

loss or structural damage. Soil microbes

are a critical part of soil health because

of the role they play in nutrient cycling

and building soil aggregates. Soil

aggregates are clumps

of soil particles that

are bound together,

leaving more available

space for air and water.

Aggregates are held

together by organic

matter (like roots),

organic compounds

(produced by soil

microbes), and fungal

hyphae. Microbes get

nutrients and energy

food for soil microbes which increases

their activity and population. Consider

this: soil microbes are necessary for the

conversion of nitrogen from one form

to another (like ammonium to nitrate)

and they need carbon to thrive.

Maintaining Soil Coverage

Bare soil is more susceptible to wind

and water erosion, as well as to surface

compaction. Our topsoil is the most

nutrient-rich part of the profile so when

we lose soil to erosion we are losing our

most valuable soil to the environment.

Although loss of soil to erosion may

seem minor from year to year, when

we consider that it takes 500 years

to form an inch of topsoil, if we are

losing just 1/100 of an inch of topsoil

to erosion a year, we are still losing soil

five times faster than it is being formed.

Surface compaction develops when

rain and irrigation water hits tilled soil,

which forms a soil crust. Maintaining

soil coverage throughout the year

physically protects soil and provides

a range of other benefits like reducing

soil evaporation rates, moderating soil

temperature, and suppressing weed

growth. In annual systems we can keep

our soil covered by planting a cover

crop during our fallow season. Keeping

crop residue on the field is also effective

(Figure 1).

Minimize Soil Disturbance

As described above, soil microbial

activity is critical for soil aggregate

formation and stability. Tillage practices

disrupt this activity and break the

fungal hyphae and roots that are

holding aggregates together. Although it

may seem that tillage increases soil pore

from the carbon found

in soil organic matter.

This is the reason

that many soil health

practices involve

increasing soil organic

matter—it provides Continued on Page 24


Progressive Crop Consultant July /August 2019


100% Fully Composted Dairy Manure

The Leaders in Dairy Compost Manufacturing

Custom Blending Available

Gypsum - Limestone - Sulfur


Servicing the Valley since 1925


What can Cain do for you?

Ask us about our Dust Control and July /August Fertilizer 2019 Products. 23

Figure 2: Direct seeding corn into wheat stubble in

Five Points, California.

Continued from Page 22

space, this benefit is short lived. This is

because individual particles break off

aggregates in recently tilled soils and

can fill in pore spaces. A healthy soil

has about 50 percent open pore space

(half filled with air and half filled with

water). Soil pores are where roots grow

and microbes thrive. There are other

management practices to minimize

soil disturbance. These include not

working or driving over soil when it is

wet, distributing tractor weight over a

larger surface area to reduce pressure

on specific points in the field, and

reducing the number of trips over a

field when possible. Even if converting

to no-till isn’t realistic for your farm,

reducing the number of passes with

the disc over a field and using vertical

instead of horizontal tillage are ways to

minimize soil disturbance. California

farmers in a number of regions are

now experimenting and sharing their

experiences with reduced disturbance

production systems like direct seeding

into crop residue from the previous

crop with little soil disturbance (Figure

2). Ongoing summaries of this work

may be found at

Keep a Living Root in the Soil

Plant roots release small carbon-based

compounds called root exudates,

which are a mix of sugars, amino acids,

enzymes, organic acids and other

compounds. These exudates can help

breakdown mineral nutrients, leading

to increased soil fertility. They also serve

as a source of food for soil microbes.

Maintaining a living root in the soil

helps keep our soil alive throughout the

year. Many beneficial microbes cannot

survive in a low-carbon environment

and keeping a living root is yet another

Photo courtesy of Jeff Mitchell.

24 Progressive Crop Consultant July /August 2019

tool for maintaining

consistent soil carbon

levels. In general,

keeping our soils alive

throughout the year will

increase soil function.

Cover crops that are

inserted into rotations as

possible are a means for

achieving this soil health

principle. As part of a

California Department

of Food and Agriculture

Healthy Soils Program

grant, my colleagues

and I are experimenting

with planting cover

crops during the fallow

season. In San Joaquin County, UC

Cooperative Extension farm advisors

Michelle Leinfelder-Miles

and Brenna Aegerter, are

researching the effects of

a warm-season legume

cover crop between winter

small grains rotations.

In Sutter County, Amber

Vinchesi-Vahl and I are

researching the effects

of a winter cover crop, at

different seeding rates,

between summer cash

crops (Figure 3). Our

projects are entering the

second of a third-year

project, and we look

forward to reporting the

results on soil health and

crop yields in the future.

Incorporate Plant Diversity

In annual systems this is called crop

rotation. Crop rotation is beneficial

for many reasons. It breaks disease

cycles by starving out pathogens that

can only thrive on specific plants

(or plants in a specific family). In

addition, crops with different rooting

depths will mine nutrients, release

carbon compounds, and improve soil

structure at different depths of the soil

profile. Finally, plants form symbiotic

relationships with various microbes,

but these relationships are often species

specific. When we incorporate plant

diversity into our systems we also build

up the diversity in our soil microbial

populations. In perennial systems, plant

diversity can be achieved by planting a

cover crop in between crop rows.

Although soil biology is an important

component of soil health, it is not the

only consideration. It’s also important

to remember the rules of soil fertility

including the 4Rs and the Law of the

Minimum. As a reminder, the 4Rs refer

to the Right Rate, the Right Source, the

Right Timing, and the Right Mode of

Application. These principles allow us

to optimize our fertilizer application

by ensuring the greatest nutrient use

efficiency. This reduces the risk of loss

to the environment and can increase

the bottom line. Liebig’s Law of the

Minimum refers to the idea that the

limiting factor has to be addressed

first. In other words, the soil issue (pH,

nutrient status) that is most restricting

yield is the one that has the greatest

potential to improve yield. If the pH is

yield limiting, no amount of fertilizer

application will fix this problem.

Photo courtesy of Sarah Light

Photo courtesy of Sarah Light.

Figure 3: Winter vetch cover crop (with volunteer

wheat) in Meridian, California.

Maintaining soil health is the long game

and changes may not be apparent for

several years. However, the more the

management practices outlined above

are incorporated into our farming

systems, the greater the likelihood of

long-term viability and protection of

arable land. In addition to the benefits

already discussed, soil water dynamics

can be improved by increased water

infiltration and water storage. Every

farming system is unique and some of

the practices may be cost-prohibitive

or not viable for some other reason.

The goal should be to incorporate as

many of the practices that will work in

our farm systems as often as we can.

Every opportunity to build and protect

our soil will ensure the long-term

economic viability of our farms, as well

as food security for our growing global


Comments about this article? We want

to hear from you. Feel free to email us at


That performs

KTS® (0-0-25-17S) is the liquid fertilizer California’s top growers depend on for healthy

crops and better yields. No other liquid fertilizer delivers more potassium and sulfur

than KTS®. KTS® blends well with other fertilizers and is easily injected, making it

immediately available for plant uptake. Maximize your potassium applications this year

with KTS® from TKI Crop Vitality.

Crop Vitality Specialists can provide assistance regarding application, blending,

field studies and technical data.

KTS® liquid crop nutrition.

Start a Conversation today with Your Crop Vitality Specialist

Call (800) 525-2803, email or visit

©2019 Tessenderlo Kerley, Inc. All rights reserved. KTS ® is a registered trademark of Tessenderlo Kerley, Inc.

July /August 2019


Iron Deficiency

in Fruit and Nut Crops in California

BY MOHAMMAD YAGHMOUR, | Area Orchard Systems Advisor, Kern County

PHOEBE GORDON, | Area Orchard Systems Advisor, Merced County

Micronutrients play a very

important role in fruit and

nut tree growth and development.

Iron (Fe), which is an immobile

micronutrient in the plant, is associated

with chloroplasts and plays a role

in chlorophyll synthesis. While Fe is

considered the fourth most abundant

element in the Earth’s crust, approximately

five percent by weight, iron

deficiency is a worldwide problem, and

a common micronutrient deficiency in

fruit and nut crops (Figure. 1) though it

is uncommon in California.

Many orchards in the Central Valley

are on semi-arid soils in areas where

the evapotranspiration exceeds

precipitation. Arid and semi-arid soils

can also be found in the southwestern

USA and the Mediterranean areas. In

this article we will be focusing more

on calcareous soils with free calcium

carbonate (CaCO3) and soil solution pH

in the alkaline range (i.e. above 7.5).

Before we get into the specifics of iron

in the soil solution, we’ll give a brief

Photo courtsey of Mohammad Yaghmour.

Figure 1. Advanced iron deficiency on almond tree in Kern County. Interveinal

chlorosis are a typical symptoms of iron deficiency.

26 Progressive Crop Consultant July /August 2019

description of pH. It indicates the

concentration of H+ ions (protons)

in a solution. Soils with low pH have

more H+ ions than soils with a high

pH. Because the equation is actually a

logarithm (Equation 1), the amount of

H+ ions does not increase linearly as

pH decreases, it increases by a factor of

10. Thus, water with a pH of 5 has 10

times the amount of H+ protons than

water with a pH of 6. Therefore, it is

progressively harder to correct soil pH

the farther it is from 7.

pH = -log[H+]

Equation 1: equation for conversion of

the concentration of H+ ions in solution

to pH. Since the equation is logarithmic,

there is a 10x difference between

consecutive values.

Soil pH is important as the different

soil minerals that contain and release

iron (Fe) into the soil-water solution

decrease in solubility as pH increases,

which results in only a tiny fraction

of the total Fe that is in the soil to

be available. In general, iron is more

soluble and more available as pH

decreases (acidic

soils). Plants

absorb some iron

by diffusion at the

root tips from the

soil solution, and

iron deficiency

in California is

mainly due to

plants’ inability

to take up iron

due to soil factors

such as poor soil

aeriation and/or

high concentration

of HCO3- in the


Under low iron availability in the

soil, the ability of trees and plants to

mobilize iron immediately around

the root is due to differences in genes

between species. Scientists have

categorized plants either as “Strategy

I’ or ‘Strategy II’ based on their ability

to mobilize Fe in the soil and make it

available for uptake. Strategy I plants

include all plants except grasses and

include fruit and nut trees, while

Strategy II plants comprise grasses such

as wheat and corn. Under Fe deficient

soil conditions, Strategy I plants excrete

H + into the soil, which acidifies it and

makes iron more available for uptake.

In poorly aerated calcareous or

saturated soils, carbon dioxide will

become trapped in the soil due to poor

gas exchange with the atmosphere.

This will cause the production and

accumulation of bicarbonates as a

result of the interaction between CO2

and calcium carbonates in the soil.

Bicarbonates react with the H+ released

by roots and interfere with their ability

to increase iron availability.

Symptoms of Iron Deficiency

The development of Fe deficiency

symptoms is most prominent on

young, newly developing leaves

(Figure 2, see page 28) because this

element is immobile in the plant.

The symptoms are characterized by

interveinal chlorosis, (Figure 3, see

page 28). Under severe conditions,

leaves have a white coloration due to

the disappearance of chlorophyll, and

leaves can turn necrotic and abscise.

Leaf chlorosis due to iron deficiency

reduces photosynthesis and will result

in reduced fruit yields and fruit quality.

These attributes are only for iron

deficient plants; overfertilizing with iron

will not increase these functions in the

Continued on Page 28

Donʼt leave out this critical part of your nutrition program!



Zinc-Shotgun is a fertilizer that focuses on micronutrients to satisfy needs of customers seeking high zinc with manganese,

iron and copper. The micronutrients are completely chelated with natural organic acids, amino acids, and carbohydrates

that are readily bio-degradable and supply energy to the plant and soil microflora.

For more information visit us online at

Call (209) 720-8040 today to create a plan that’s best for you.

We’re always here to help.

Call: 1-844-WRT-LIFE


July /August 2019


plant. Continued from Page 26

Pre-Plant Management

of Iron Deficiency

The first step in assessing an orchard

is site selection, followed by collection

of representative soil samples for

analysis based on the United States

Department of Agriculture (USDA)/

National Resources Conservation

Service (NRCS) soil survey map. Send

these soil samples to a commercial

laboratory you trust to look at soil pH

and the presence of free lime. It’s also

helpful to get a water analysis to look

for water pH and bicarbonates. When

choosing a site, try to plant in a welldrained

soil. Adequate root aeration

will reduce the likelihood of iron

chlorosis occurring. If the irrigation

water contains more than 2 meq/L

of bicarbonates, you may consider

acidifying the water to a pH of 6.5

to reduce bicarbonate levels by 50

percent and prevent lime buildup in

the soil and in your irrigation system.

An agricultural laboratory can do a

titration curve, which will tell you how

much acid to add to decrease the water

pH. We do not recommend decreasing

irrigation water pH below 5.0.

Alternatively, 133 pounds of 100 percent

sulfuric acid will neutralize 1 meq/l per

acre-foot of bicarbonate in irrigation

water. Water acidification can be

achieved by using acids such as sulfuric

or phosphoric acid. Make sure you tell

your laboratory what acid you intend to

28 Progressive Crop Consultant July /August 2019

Figure 2. Iron deficiency on newly growing leaves on an almond tree in Kern County with leaves showing

interveinal chlorosis.

use, as substituting one acid for another

can result in incomplete or overacidification.

Urea sulfuric acids, such

as N-PHuric 10/55 and US-10, will also

acidify the soil and are safer to handle,

however, application rates should not

exceed nitrogen (N) crop requirements,

which limits its use for acidification.

Some growers use a “sulfur burner”,

which will convert elemental sulfur

into sulfurous acid (H2SO3) by burning


sulfur in a

small furnace


sulfur dioxide


Combination of

SO2 and water

in the machine

will form

sulfurous acid

that is injected

in the irrigation



acid is safer

than sulfuric

acid injection.


burners have

a minimum

design and


Photo courtsey of Elizabeth Fichtner.

Photo courtsey of Mohammad Yaghmour.

capacity potentially making the capital

investment too expensive for smaller

farms to consider.

Acidification can be expensive and

in extreme cases may not be viable to

reduce pH in soils with a lot of free

lime, as it will require large quantities of

acid forming amendments to react with

soil lime before the bulk soil pH begins

to decrease. It takes approximately

half a ton of soil sulfur to break down

one percent calcium carbonate in one

acre-inch of soil. To manage these costs,

soil amendments such as elemental

sulfur or sulfuric acid can be banded or

shanked in the tree row before planting.

However, warm soil temperatures and

soil bacteria are needed to convert the

elemental sulfur to sulfuric acid and

depending on the source of sulfur and

its influence on particle size, structure,

and solubility of the sulfur this may take

several weeks to years to break down.

Acids work much faster but are more

expensive. It is important to remember

that any acidification will break down

free lime in the soil before the bulk soil

pH is changed.

Rootstock choice is one of the most

important choices you or your client

will make before planting an orchard.

This choice should be based on the

site challenges such as pH, salinity,

Figure 3. Iron deficiency on newly growing prune leaves.

Continued on Page 30

Helping Farmers Grow


Since 1974

Helping Farmers Grow NATURALLY Since 1974

Organic Products & Services

• Compost

• Custom Blends

• Vitazyme TM

• Gypsum

• Limestone

• Root Stimulants

• Liquid Fish Fertilizers

• Mycorrhizae Fungi

• Leaf Test

• Acadiam TM Seaweed Extract

• Liquid Compost

• Liquid R/S

• Foliar Nutrients

• Liquid Potassium

• Humic Acid

• Yucca Saponin Extract

• Soil Test

Certified Crop Advisors on Staff

Contact Us Today!

Doug Graham Certified Crop Advisor License #329563

Tel 559-686-3833

2904 East Oakdale Ave. Tulare, CA 93274

July /August 2019


Change in pH for a Loam Soil

8.5 to 6.5

8.0 to 6.5

7.5 to 6.5

7.0 to 6.5

Pounds of Soil Sulfur to

Modify a 6-inch Slice





Table 1. Amount of soil sulfur needed to modify a loam soil. Adapted from the Western Fertilizer

Handbook, 9th Edition.

Continued from Page 28

nematodes, and risk of bacterial

canker, for example. If high soil pH

and concern about iron deficiency is

the most important factor to resolve,

then use of Fe deficiency tolerant

rootstocks is a good solution. Some

of the rootstocks that are considered

tolerant include some of the (peach

X almond) hybrids such as Hansen

536, Bright’s, Titan, and Paramount

(GF 677). However, these rootstocks

are very susceptible to other soil

issues such as poor drainage and

root diseases, so pick your rootstock

carefully. Other rootstocks tolerant

to Fe deficiency are Krymsk86 which

is a peach/plum hybrid used for

almonds and Gisela 5 used for cherry


Post-Planting Management

of Iron Deficiency

After planting the trees, if your soils

do not have a large amount of free

lime, the best management practice

is acidifying the soil around the

root zone. This can be done using

elemental sulfur or the injection of

acids as described before, however

you can easily damage your trees

through acid injection so follow

directions carefully. Do not apply

sulfuric acid in established orchards

at more than 1500 lbs per treated

acre to prevent tree damage.

Elemental sulfur takes longer but is

safer for the trees. It is often more

economical to acidify a band of soil

rather than attempting to acidify the

entire root zone.

Another way to correct iron

deficiency after planting is to apply

foliar and soil chelated Fe which will

result in a faster response. However,

it is short-lived, expensive, and can

be leached below the root zone under

heavy irrigation. Chelated Fe most

likely will need to be applied multiple

times in the orchard’s lifetime.

Applications of ferrous sulfate to the

soil or the tree is a cheaper option

compared to chelated Fe. However,

in calcareous soils it will very quickly

become unavailable for uptake and

is not an appropriate option in these


Comments about this article? We want

to hear from you. Feel free to email us



Elkins, R., and Fichtner, E. (2012). Causes

and control of lime-induced Fe deficiency

in California fruit and nut crops. CAPCA

(California Association of Pest Control

Advisers) Advisor. August 2012.

Lauchli, A., and Grattan, S., R. (2012). Soil

pH Extremes in: Plant Stress Physiology.

CAB International, Editors: S Shabala,


Sanden, B., L., Prichard, T., L., and Fulton,

A., E. 2016. Assessing and Improving Water

Penetration in: Pistachio Production

Manual. UC ANR publication 3545, Editors

Louise Ferguson and David Haviland,

pp. 141-152.

Tagliavini, M., and Rombola, A., D. 2001.

Iron deficiency and chlorosis in orchard

and vineyard ecosystems. European Journal

of Agronomy 15: 71-92.

30 Progressive Crop Consultant July /August 2019

powered by:






PCA Hours:

CCA Hours:



ONLY $100

per person

Workshops and Seminars

Mixer & Networking

Meals Included

(Breakfast, Lunch and Snacks)

Full Gala Dinner

Live Entertainment

(Jason Bird, Magician and Illusionist)

Over 50 Exhibits


September 26th

1:00PM - 9:00PM

September 27th

7:00AM - 1:00PM

September 26th-27th

Visalia Convention Center

303 E. Acequia Ave. Visalia, CA 93291

See pages 32-35 for the Agenda and Application.


Agenda Sponsor Indoor Sponsor Coffee Break Sponsor Indoor Sponsor Breakfast Sponsor Indoor Sponsor

Lanyard Sponsor

Indoor Sponsor

Mixer Sponsor

Mixer & Tote Bag Sponsor

CE Credit Sponsor

July /August 2019



September 26




Getting the Most out

of Your Soil

Richard Kreps, CCA


How to Optimize IPM and

Nutrient Management using

Aerial Drone Technology

Mark Dufau, Director of Business Development for



Managing Botrytis in a

Challenging Year

Gabriel Torres, UCCE Farm Advisor, Tulare County

CE Credits: 30 Minutes; Other


The Latest in HLB and Asian

Citrus Psyllid Management

Greg Douhan, UCCE Area Citrus Advisor for Tulare,

Fresno, and Madera Counties

CE Credits: 30 Minutes; Other


Navigating Fungal Diseases

Themis Michallides, Professor and

Plant Pathologist UC Davis

CE Credits: 30 Minutes; Other


Paraquat Closed Transfer

System (New EPA

Guidelines for 2020)

Charlene Bedal, West Coast Regional


CE Credits: 30 Minutes; L & R


Mixer/Trade Show

CE Credits: 30 Minutes; Other




Future of Agriculture

Chemicals in California

Speaker TBD

CE Credits: 30 Minutes; Other


Jason Bird

Magician and Illusionist

Jason Bird creates experiences that inspire

people. He reawakens their sense of wonder

and reminds them of how cool it is to

be alive. In addition to the millions who

have seen him on television, Jason Bird

has cast his spell for audiences around the

world in large theatrical venues as well as

intimate settings.

Jason Bird will perform small group illusions

during the trade show / mixer from 5-6PM

32 Progressive Crop Consultant July /August 2019



2-Day Agenda

Attendee Registration

7.5 Hours of PCA

Other: 5.75

Laws and Regulations: 1.75

9.0 Hours of CCA

(Tentative Do Agenda/Pending you wish to receive/continue CE Approval) receiving our free monthly Publicatons?

West Coast Nut Progressive Crop Consultant Organic Farmer


Full Name:


September 27








Label Update

CE Credits: 50 Minutes; L & R

8:50AM County:

Evaluation of Mating


Disruption as Part of an IPM


Primary Business/Occupation (Check only one) Secondary Business/Occupation (Check all that apply)


Independent PCA

Chuck PCABurks USDA Independent PCA


Dani Casado, Ph.D. in Applied Chemical Ecology, Sutterra

Independent CCA


Independent CCA

Jeannine Lowrimore, Pacific Bio Control

Grower Ag Retailer

Grower Ag Retailer

Applicator Other

CE Credits:


40 Minutes; Other





/ Going Above and

Beyond for Your Grower –

Keeping them Compliant

Patty Cardoso, Director of Grower Compliance for

Gar Tootelian, Inc.

Attendee Name:

Attendee Name:

September 26th-27th

Visalia Convention Center



Trade Show

CE Credits: 30 Minutes; Other



powered by: 9:30AM

Regulatory Impacts on


California Crop Protection






303 E Acequia Ave, Visalia, CA 93291

# Of Attendees:

Total: $


July /August 2019

Workshops Together and Seminars

Mixer & Networking

Meals Included

(Breakfast, Lunch and Snacks)

Full Gala Dinner

Live Entertainment

(Jason Bird, Magician and Illusionist)

Over 50 Exhibits


(One commodity per line) Acres Commodities (One commodity per line) Acres

Attendee Tickets cost $100 per person. Please list the full name of each attendee as you want it to

appear on your name badge.




Internal Use Only: CSH___ CC___ CHK___ INT___




powered by:




PCA Hours:


Trade Show

CE Credits: 30 Minutes; Other



Panel—Top Insects Plaguing

California Specialty Crops—

BMSB, Mealy Bugs/NOW

Spotted Wing Drosophila

David Haviland (Mealy Bugs/NOW)

(Gala Dinner,



Cooperative Extension, Breakfast, Kern County, and snacks)

Kent Daane (SWD) Cooperative

Extension Specialist, UC Berkeley,

Jhalendra Rijal (BMSB) UCCE IPM

Advisor for northern San Joaquin Valley

CE Credits: 60 Minutes; Other



September 26th-27th

Visalia Convention Center

303 E. Acequia Ave.

Visalia, CA 93291

Drink Ticket on Us


Meals Included


A New Approach to IPM

Surendra Dara, Entomology and Biologicals Advi-

Matthew Allen, Director, California Government Affairs,

Western Growers

sor, University of California Cooperative Extension

By checking yes, you agree to give JCS Marketing permission on a

CE Credits: 30 Minutes; L & R

monthly basis CE to Credits: mail industry 30 related Minutes; updates, third Other party emails

Yes No

and newsletters via email.

CCA Hours:


per attendee


Please Mail Applications to

Progressive Crop



P.O. Box 27772 Adjourn Fresno, CA 93729



x $100




For Sponsorship Opportunities call (559) 352-4456 TODAY!


Company Name: ____________________________________________________________________

Company Address: ___________________________________________________________________


September 26

City: _______________________________ State: __________________ Zipcode: _______________

Company Phone: ________________________________ Email: ______________________________

Event Contact Name: ___________________________________ Cell Phone: ____________________




Getting the Most out

of Your Soil

JCS Marketing Use Only:

Digital Guide:

34 Progressive Crop Consultant July /August 2019


Navigating Fungal Diseases

Themis Michallides, Professor Company and Name:

Plant Pathologist UC Davis

Attendee Name(s): 2 Attendees Included with Booth

CE Credits: 30 Minutes; Other



Paraquat Closed Transfer

System (New EPA

Guidelines for 2020)

Two conference Richard registrations Kreps, CCA are included with each


booth purchase.

Charlene Bedal, West Coast Regional

Manager, HELM AGRO 2) US

registration fee for each additional attendee.


How to Optimize IPM and

Nutrient Management using

Advertiser Aerial Drone - Special Technology Pricing


CE Credits: 30 Minutes; L & R



Mixer/Trade Show

CE Credits: 30 Minutes; Other




Future of Agriculture

Chemicals in California

Signature: _________________________________________________Date: ____________________


Indoor Booths

Optional Extras: Check (if applicable)

Mark Dufau, Director of Business Development for

Do you AeroVironment

currently advertise in our publications?

West Coast Nut, Progressive Crop Consultant, and Organic Farmer

(Total Package Savings of $150)

Booth Attendants:

Enter all of the information below as you would Speaker like it to TBD appear on name badges.

CE Credits: 30 Minutes; Other


Jason Bird

Magician and Illusionist

Full Page Ad in the NEW Digital Guide

Optional Extras: $

Managing Tote Botrytis Bag Insert in a

Jason Bird creates experiences that inspire

Challenging Year

Total Amount Due: $

people. He reawakens their sense of wonder

Gabriel Non-Advertiser Torres, UCCE Farm Pricing Advisor, Tulare County

Payment and completed form are




to secure









it is to

CE Credits: 30 Digital Minutes; Guide Other & Tote Bag Insert Combo

payment with this completed form to JCS Marketing PO Box 27772, Fresno, CA

With this option you save $50, receive a tote bag insert 93729. Make checks payable to be JCS alive. Marketing. In addition to the millions who

and a full page ad in our NEW Digital Guide!

**All credit card payments are




to a 3%



on television,


Jason Bird

3:30PM Digital Guide Full Page Ad

has cast his spell for audiences around the

The Latest



ad will




in our


NEW Digital Guide

Interested in a FREE booth?

Check out our sponsporship world in large opportunities theatrical venues at as well as

Citrus Psyllid Tote Management

Bag Insert

or call today for special custom pricing intimate on settings. advertising packages.

Greg Douhan, Put UCCE an Area insert Citrus into Advisor our tote for Tulare, bag to go to every attendee.


Fresno, and Madera Counties

CE Credits: 30 Minutes; Other

Jason Bird will perform small group illusions

$1,000,000 for each occurrence. Mail to JCS Marketing PO Box 27772, during Fresno, the CA trade 93729. show / mixer from 5-6PM


Additional Attendees: $100 per additional attendee

Please enter the total amounts for all of the options you selected below.

Standard Booth: $

Additional Attendees: $

September 26-27, 2019

9/26 1:00pm-9:00pm | 9/27 7:00am-1:00pm

Visalia Convention Center

303 E Acequia Ave, Visalia, CA 93291



2-Day Agenda

7.5 Hours of PCA

Other: 5.75

Laws and Regulations: 1.75

9.0 Hours of CCA

(Tentative Agenda/Pending CE Approval)


303 E Acequia Ave, Visalia, CA 93291

Workshops and Seminars

Mixer & Networking

Meals Included

(Breakfast, Lunch and Snacks)

Full Gala Dinner

Live Entertainment

(Jason Bird, Magician and Illusionist)

Over 50 Exhibits



September 27


Breakfast / Going Above and

Beyond for Your Grower –

Keeping them Compliant

Patty Cardoso, Director of Grower Compliance for

Gar Tootelian, Inc.


Trade Show

CE Credits: 30 Minutes; Other


Label Update

CE Credits: 50 Minutes; L & R


Evaluation of Mating

Disruption as Part of an IPM


Chuck Burks USDA

Dani Casado, Ph.D. in Applied Chemical Ecology, Sutterra

Jeannine Lowrimore, Pacific Bio Control

CE Credits: 40 Minutes; Other


Regulatory Impacts on

California Crop Protection


Matthew Allen, Director, California Government Affairs,

Western Growers

CE Credits: 30 Minutes; L & R




Trade Show

CE Credits: 30 Minutes; Other


Panel—Top Insects Plaguing

California Specialty Crops—

BMSB, Mealy Bugs/NOW

Spotted Wing Drosophila

David Haviland (Mealy Bugs/NOW) UC

Cooperative Extension, Kern County,

Kent Daane (SWD) Cooperative

Extension Specialist, UC Berkeley,

Jhalendra Rijal (BMSB) UCCE IPM

Advisor for northern San Joaquin Valley

CE Credits: 60 Minutes; Other




A New Approach to IPM

Surendra Dara, Entomology and Biologicals Advisor,

University of California Cooperative Extension

CE Credits: 30 Minutes; Other



July /August 2019



Deficiency in



1. Magnesium deficiency in Scarlet Royal table grapes.

Photo courtsey of Matthew Fidelibus.

BY MATTHEW FIDELIBUS | Extension Specialist, Department of Viticulture and Enology, UC Davis

When most California grape growers think

of macronutrients, nitrogen (N) and potassium

(K) are rightfully at the top of list, as

these two mineral nutrients are needed in relatively

high amounts and are commonly supplemented with

fertilizer applications. However, magnesium (Mg) is also

considered a macronutrient, though it is needed in much

lower amounts than N or K. Even so, it is not uncommon

to observe Mg deficiency symptoms, especially in certain

grape varieties which appear to be particularly prone to

Mg deficiency, including Barbera, Grenache, Redglobe,

Thompson Seedless, and Zinfandel. Recently, I have heard

from several growers that some of the newer table and raisin

grape varieties also appear to be prone to Mg deficiency.

Rootstocks also differ in their ability to take up Mg. For

example, 1103P is considered to be good at amassing Mg,

whereas Riparia Gloire (Vitis riparia), and some V. riparia

hybrid stocks are less effective at amassing Mg.


Magnesium is a central component of chlorophyll, and

by mid to late summer, the leaves of Mg-deficient vines

typically develop a distinctive creamy-white chlorosis

along the margin of basal leaves. The primary and

secondary veins of the leaves retain a dark green color,

resulting in a Christmas-tree pattern on the leaf (Figure

1). In red varieties, the leaf margins may develop red

color (Figure 1), and in severe deficiencies, the margin

may become necrotic, brown colored, and dry. Analysis

of petiole samples can be useful in verifying Mg

deficiency. Petioles collected at bloom should contain >0.3

percent Mg.

Magnesium plays a critical role in enzymatic reactions,

including the activation of adenosine triphosphate (ATP).

Magnesium deficiency impairs the loading of sucrose

into phloem in leaves, thereby causing carbohydrates

to accumulate in leaves, while reducing the supply of

carbohydrates to other organs that need them. Thus, Mg

deficiency could theoretically limit the vine’s ability to

produce and distribute carbohydrates. Australian research

has linked low Mg levels in rachises with bunch stem

necrosis (BSN), and in such cases, application of Mg

reduced BSN. Vines with Mg-associated BSN sometimes,

but not always, had leaves with Mg deficiency symptoms.

However, studies in California have not verified a link to

Mg and BSN.

Magnesium is Moderately Leachable in Soil

Magnesium is moderately leachable in soil and tends to

be most abundant in subsoil and least abundant in the

surface layers, especially on weathered soils. Young vines

are more susceptible to Mg deficiency than older vines,

probably because the roots of young vines have likely not

explored as much of the subsoil as the roots of older vines.

Thus, vine age, particularly the age of the root system (if

on topworked vines), should be considered when assessing

the relatively susceptibility of new varieties to Mg

deficiency. Removal with the harvested crop can further

reduce Mg in a vineyard, though previous studies suggest

that grape berries only amass about 0.2 lbs Mg/ton of fruit.

The Mg concentration in soils can be easily measured, but

critical soil values have not been established, and it would

be very difficult to account for the possible supply of Mg

in the subsoil that may be available to the vine.

As noted above, Mg deficiency can occur due to

insufficient Mg in the root zone, a limited root system,

or both. However, Mg deficiency can also be induced

by soil acidification (pH < 5.5), which can occur after

years of irrigation and fertilization. High levels of other

cations, especially K and calcium (Ca) compete with

Mg for uptake by roots. Thus, an imbalance in K or Ca

Continued on Page 38

36 Progressive Crop Consultant July /August 2019

The 5 R’s of foliar nutrition are - apply the Right nutrients,

in Right form, at the Right time, in the Right mix and in the

Right place. Applying effective nutrients based on a “Science

Driven” approach that DO penetrate leaf tissue ensures

your crop is getting the nutrients it needs at the right time.

The form of foliar nutrients DO matter. Many foliar nutrient

formulations are built on large chain molecules or unreacted

oxides or carbonates that are not in-solution. These types of foliar

nutrients and others have limited uptake on most leaf surfaces.

Agro-K has three main foliar lines – one based on phosphite

(Sysstem ® ) another based on dextrose/lactose (Dextro-Lac ® )

and a third for organic growers (CLEAN ). They are true 100%

nutrient solutions based on low pH small molecular formulations

that penetrate leaf tissue rapidly and completely.

Rapid and complete uptake of foliar applied nutrients

gives growers the ability to effectively meet “peak nutrient

demand” timing. Whether you’re applying zinc for rapid leafout

to maximize leaf size, or magnesium and iron to ensure

maximum chlorophyll development or potassium for fruit

bulking, if nutrients do not go in quickly and fully then your

foliar dollars are less effective and yield and quality suffers.

Make sure you know how well your foliar nutrients penetrate.

Ask for SAP analysis comparisons.

The chart shows three Agro-K zinc formulations, Sysstem-ZN,

Zinc Dextro-Lac and CLEAN Zinc were applied to Viognier

grapes on August 8th, along with a commonly available

competing zinc amino acid product. Leaves were pulled prior to

application and eight days after treatment. SAP analysis, which

measures only the free-nutrients available within the leave sap,

Science-Driven Nutrition SM

Do you know if your

foliar nutrients are getting in?

the form of foliar nutrients do matter!






Viognier Wine Grapes

Zinc levels (ppm) via SAP Analysis

4 5 4 3

5 5


8 Days After Treatment

n UTC n Sysstem ZN n Zinc DL n Clean Zinc n Competing Zinc Amino Acid

showed that zinc levels prior to zinc applications were the same

for all treatments in this fully replicated trial. SAP analysis eight

days later shows all three Agro-K foliar products were far more

effective than the competing amino acid product in delivering

zinc into the leaf tissue where it matters.

This year make sure you know the efficacy of your foliar

fertilizers before you spray! Talk to an Agro-K representative

or your authorized Agro-K distributor and/or PCA for more

information on foliar nutrients that truly WORK!. Call 800-328-

2418, visit, or email


8030 Main Street, NE • Minneapolis, MN 55432

800-328-2418 •

July /August 2019



© 2019 Agro-K Corporation.




Continued from Page 36

may induce Mg deficiency. Peacock

and Christensen (1996) suggests Mg

deficiency is most likely when the Mg

saturation of cation exchange capacity

of the soil is

Navel Orangeworm Control!

Mating disruption product for conventional and organic California tree nuts!!



Navel Orangeworm,

Amyelois transitella

• Up to 80% or more potential reduction in

damage vs. current insecticide program

• Season-long control through post-harvest

• Easy application with ready-to-use

carrier pack

• No moving parts, no batteries, no

gummy deposits

• Removal not required




Your Edge – And Ours – Is Knowledge.




Contact your local supplier and order now!

Visit our website: or call: 1- 866-785-1313.

© 2019 , Trécé Inc., Adair, OK USA • TRECE, PHEROCON and CIDETRAK are registered trademarks and

TM is a trademark of Trécé, Inc., Adair, OK USA • TRE-1578, 6/19

July /August 2019


All photos courtsey of Florent Trouillas.

Neofabraea Leaf and Twig Lesions

A New Disease of


Olive trees

BY FLORENT TROUILLAS | Cooperative Extension Assistant Specialist in Plant Pathology

University of California, Davis

Figure 1: Neofabraea leaf lesions on

Arbosana olive.

40 Progressive Crop Consultant July /August 2019

Neofabraea leaf and

twig lesions were first

detected in California

super-high-density oil olive

orchards in 2016. Since then the

disease was found in Glenn, San

Joaquin, and Stanislaus Counties.

Causal agents of this new disease of

olive were identified as Neofabraea

kienholzii and Phlyctema vagabunda

(syn: Neofabraea vagabunda).

Phlyctema vagabunda is known in

Spain as the causal agent responsible

for the olive leprosy or lepra

fruit rot, causing fruit malformation

as well as leaf lesion and twig

canker. This disease is of increasing

concern in Spain, Portugal and

Italy. Dr. Trouillas at UC Davis has

outlined the disease epidemiology,

disease cycle, and determined best

spray timings and materials that

will help to control this disease.

Disease Symptoms

Neofabraea leaf and twig lesions

are primarily associated with

wounds, such as those sustained

during mechanical harvest. Leaf

lesions are circular to elongate,

necrotic, approximately 0.5 to 1cm

in diameter and normally do not

number more than one lesion per

leaf (Figure 1, see page 40). Twig

lesions are reddish-brown in color

mainly affecting the bark tissues

(Figure 2, see page 42). The disease

may occasionally cause fruit rot

near the time of harvest. In severely

infected orchards, defoliation and

fruit loss may occur.

Disease Biology

Two fungal pathogens have been

identified using morphological and

molecular techniques: Neofabraea

kienholzii and Phlyctema

vagabunda (syn: Neofabraea

vagabunda). These pathogens have

been associated with bull’s eye rot

and canker of apples and pears in

the Pacific Northwest.

In olive, the disease has been

detected primarily from superhigh-density

oil olive orchards in

Glenn, San Joaquin and Stanislaus

counties. The cultivar ‘Arbosana’

is the most susceptible but the

disease has also been isolated on

occasion from ‘Arbequina’ olives in

the Central Valley. It was not found

in the Koroneiki cultivar. Previous

reports of the disease in California olive

have included fruit spots in ‘Cortina’,

‘Picholine’ and ‘Frantoio’ varieties in

Sonoma county. To date, table olive

varieties (Manzanillo and Sevillano)

in the Central Valley have not tested

positive for Neofabraea leaf and twig


Infection occurs at the site of plant

injuries. In super-high-density oil

olives, these wounds are typically

associated with damage caused by

mechanical harvesters but may also

include abrasion sites where leaves or

twigs rub against each other. Following

mechanical harvest, rain events allow

for fungal inoculum to be released in

the air, leading to infection of the fresh

wound sites. Leaf spot symptoms are

most visible in March, with defoliation

occurring in April and May. Infected

leaves and fruits act as inoculum

sources for infection the following year.

Disease Management

Field trials have been conducted for

three consecutive years in the highly

Keep Birds Out


“I’ve used Bird Gard

for years to protect my

growers’ crops and keep

birds from damaging

the irrigation.

Bird Gard works, what

more can I say?”

Tim Peltzer

Peltzer Farm Management

Terra Bella, CA

Continued on Page 42

Bird Gard is the ONLY bird control with a



Guaranteed Bird Control for over 30 Years!

July /August 2019


Neofabraea leaf

and twig lesions are

primarily associated

with wounds, such as

those sustained during

mechanical harvest.

Figure 2: Neofabraea twig lesions on Arbosana olive.


550 ®

Frost & Freeze

Additional Environmental Stress Conditions that the product is useful for:

What is

Anti-Stress 550®?

When to apply

Anti-Stress 550®?

Beat the Heat & Care

for Your Crops with:

• High Temperatures & Extreme Heat

• Drought Conditions

• Transplanting • Drying Winds

When is Anti-Stress 550®

most effective?

A foliar spray that creates a

semi-permeable membrane

over the plant surface.

Optimal application period is

one to two weeks prior to the

threat of high heat.

The coating of Anti-Stress

becomes effective when the

product has dried on the plant.

The drying time of Anti-Stress is

the same as water in the same

weather conditions.

*One application of Anti-Stress 550® will remain effective 30

to 45 days, dependent on the rate of plant growth,

application rate of product and weather conditions.

559.495.0234 • 800.678.7377 •

Order from your PCA or local Ag Retailer / Crop Protection Supplier

Continued from Page 41

susceptible Arbosana cultivar to determine fungicide

efficacy. Results showed that several products were effective

in reducing infection by the pathogens and limiting disease

incidence. Overall, best disease control was achieved by

Topsin M, Vanguard, Inspire Super, Bravo and Ziram

fungicides, which provided up to 75 percent reduction in

disease incidence. Copper fungicides did not control the

disease. Comparison of different fungicide application

regimes showed that one to two applications after harvest

significantly reduce disease incidence. Two independent

wound susceptibility trials were conducted also to determine

the duration (0, 1, 2, 3, 4 or 5 weeks) when wounds on leaves

remain susceptible to infection, and thus determine the

number and timing of fungicide applications required to

control Neofabraea and Phlyctema diseases. Results showed

that leaves inoculated immediately after wounding (harvest)

and those inoculated one week after wounding were the most

susceptible to infection. Overall, leaf wound susceptibility to

infection declined substantially after four weeks following

wounding. This suggests that wounds had healed after four

weeks following a wounding event at harvest and that one

fungicide application after harvest followed by a second

application two to three weeks later should suffice to protect

olive trees from infection.

Next Steps

Two fungicides were nominated to the IR-4 program

in 2018: Ziram (Ziram 76WDG) and difenoconazole/

cyprodinil (Inspire Super). These fungicides were approved


Progressive Crop Consultant July /August 2019

Comparison of different

fungicide application

regimes showed that one

to two applications after

harvest significantly reduce

disease incidence.

Enhanced Codling Moth Larval Control!

For conventional and organic California walnuts!!


40% Average Reduction Compared to Insecticide Alone *

for residue trials at the National Food

Use Workshop in September for

registration on olives. Strong support

was provided based on the afterharvest

and winter season usage with

expected zero to limit-of-detection

residues on the crop in the following

harvest season. Ziram is a FRAC

Code M3 whereas Inspire Super is a

FRAC Code 3/9. Thus, integration of

multi-site modes of action for both

products was also established as an

effective anti-resistance strategy.

Ziram and Inspire Super were also

submitted for section 18 emergency

exemptions, which are expected to

come into effect during the course

of 2020. The availability of these

two fungicides in olive will improve

control of Neofabraea and Phlyctema

leaf and shoot lesions and will

allow for management of fungicide

resistance by rotating modes of



We are thankful to the Olive Oil

Commission of California for funding

this research.

Comments about this article? We want

to hear from you. Feel free to email us at

Available in 10, 20 and

40 acre container sizes!



Your Edge – And Ours – Is Knowledge.

Simply tank mix with insecticide application

CIDETRAK ® DA MEC contains a novel, patented kairomone in a micro-encapsulated liquid formulation that

influences the behavior of adult and larval Codling Moth, resulting in significant enhancement of the control of

Codling Moth larvae when tank mixed with various insecticides. Additionally, Codling Moth adult control is significantly

enhanced when mixed indirectly with airborne Codling Moth pheromone applied as a mating disruption treatment.

• What it does: Disrupts oviposition. Changes larval behavior:

Stops/delays locating walnut; stops/delays walnut entry and reduces damage.

• How to use it: Simply tank mix with each insecticide application.

• Longevity: More than 14 days following application.


Contact your local supplier and order now!

Visit our website: or call: 1- 866-785-1313.



© 2019, Trécé Inc., Adair, OK USA • TRECE, PHEROCON and CIDETRAK are registered trademarks of Trece, Inc., Adair, OK USA • TRE-1535, 5/19

CIDETRAK DA MEC will provide a higher level

of insecticide efficacy in killing hatched larval

worms and protecting the walnut set that

the grower currently sees and counts on by

targeting the Codling Moth 1B, 2nd and 3rd

flights, with the added benefit of decreasing

damaged-nut sites for NOW to later infest.

~ Dr. Douglas Light, USDA-ARS, Emeritus


PLEASE: ALWAYS READ THE LABEL *Based on USDA analysis global data base.

July /August 2019



with our mycorrhizal products

• BACTERIAL Inoculants • Soil Products • Biological Food Products

• Micro Nutrients • Foliar Nutrients

Contact Us Today at 1-800-279-9567

44 Progressive Crop Consultant July /August 2019


Ask us about our other soil care products.

More magazines by this user
Similar magazines