Olive policy - South East Natural Resources Management Board ...

Declared Plant Policy
BACKGROUND INFORMATION
Olive (Olea europaea)
Biology
Olive is an erect, bushy evergreen tree growing to about 12 m tall with a deep, widelybranched,
woody root system. It has tiny cream flowers that appear in large clusters in late
spring. Seeds germinate mainly in autumn and seedlings grow during winter. Flowering
does not begin for several years. Flowers appear in October/November and fruit develops
slowly over summer. The ripe fruits hang on the tree for a long period during the following
winter.
Dispersal
The fruit and oil of the olive tree have a high commercial value and olives will continue to be
cultivated in South Australia because local climates are ideal for olive growing and there is a
large demand for the product. Feral olives are the consequence of an olive industry and
other cultivated olive trees. The existing feral populations are self-sustaining and are the
major source of seed for further spread, even in the absence of olive orchards.
The spread of olives is mainly due to birds and foxes eating the fruit and dropping the seeds
elsewhere. The development of olive orchards has lead to spread throughout the State.
Some seed may be moved locally in soil during earthworks. Olive grows well in most
environments, particularly where winter rainfall is high and summers dry. It will grow on a
wide range of soil types but will not survive in waterlogged soil.
Impacts
Olive is an invader of native vegetation, especially dry sclerophyll forest or woodland, and
adjoining cleared, ungrazed land. When uncontrolled, olive trees can alter the composition,
decrease biodiversity and increase the fire hazard of native vegetation. Like eucalypts,
olives are highly inflammable due to their oil content and can regenerate from stumps after
fire. As it is very long-lived, such changes are permanent unless controlled.
Current Distribution
The olive tree, Olea europaea, was introduced from the Mediterranean area as a tree crop.
It is now established in many parts of South Australia. In the South East there are isolated
plants on roadsides, some reserves and within native vegetation.
Olive policy for the SE NRM region 1

Declared Plant Policy
Olive policy for the SE NRM region 2

Declared Plant Policy
REGIONAL PRIORITY
Olive was assessed during the South East Weed Risk Assessment project. Olive is mainly a
weed of native vegetation and was not considered important in the other landuses.
Olive was not included in the top 15 agricultural weeds for the South East.
The table below outlines the management actions required and relative priorities for olive in
each landuse:
Management
Action
Relative
priority
Aquatic Crop/pasture Forestry Grazing Irrigated Native
Vegetation
Perennial
Horticulture
Urban
N/A N/A N/A N/A N/A Manage N/A N/A
Sites
- - - - - 5 - -
AIMS:
1. To protect natural environments from the loss of biodiversity caused by olive.
2. To protect the olive industry from pests and pathogens harboured by feral olive trees.
3. To reduce the distribution of olive in the South East.
OBJECTIVES:
• Identification of the full extent of olive infestations in the South East.
• Enforce control of olive infestations on roadsides and unused plantations to prevent
spread to other areas.
• Identification of important sites to be protected from olive.
• Increase awareness about the impacts of olive.
IMPLEMENTATION
State Level
• Increase awareness about the impacts of olive on native vegetation.
Regional Priority Actions for the SE NRM Board
• Authorised Officers to inspect, map and monitor all infestations of olives.
• Control of olive enforced for isolated infestations and on roadsides.
• Buffer zones enforced around all plantations of olive.
• Seek external funding for projects relating to olive control which will protect natural
environments.
• Provide risk assessment input to Local Government planning procedures regarding
approval for new olive plantations.
Olive policy for the SE NRM region 3

Declared Plant Policy
Local action
• All landholders to implement active control programs according to seasonal
conditions and the instructions of the Authorised Officer.
DECLARATIONS
The following sections of the NRM Act apply to olives (that are not planted and maintained
for domestic or commercial use) in all Local Government areas in the South East NRM
region:
182 (2)
(3)
Land owner must control the plant on their land
Land owner must take prescribed measures for the control of
the plant on their land
185 (1) NRM authority may recover costs for control of weeds on
roadsides from adjoining land owners
Implementation
Responsibility of Operations Manager
Periodic Review
Responsibility of Operations Manager
Date endorsed by the SENRMB 24 May 2006
Date scheduled for review 2011
Version Date Version Reference Sections Description of Changes
May 2006 1 Whole document Endorsed By SENRM Board
Released to public
March 2011 2 Whole document Review and update of distribution maps
Olive policy for the SE NRM region 4