Blackberry control manual - Weeds Australia

Control of blackberry is a long-term process
(Figure 4.1) and cannot be achieved by one‐off
strategies. This is particularly the case for larger
infestations.
Physical
control
(section 4.2,
p. 57)
Herbicides
(section 4.1,
p. 39)
Blackberry
Management
Indicates integration between control
options in a long-term management plan.
Biological
control
(section 4.3,
p. 64)
Figure 4.1 Overview of long-term management techniques
for blackberry.
Integrated weed management (IWM)
describes a combination of control methods
used for the long-term control of a weed.
4.1 Control with herbicides
Herbicides are highly effective tools for
controlling blackberry, and their use is the most
reliable method for achieving local eradication.
However, herbicides should be used as part of an
integrated weed management program involving
a range of control strategies. This section
provides best practice management advice
based on current knowledge and experience. It
gives information additional to that provided on
herbicide product labels.
Four factors should be considered when planning
to use herbicides:
The length of residual activity of a herbicide
depends on the rate of application, the soil
type, and the environmental conditions.
Generally, herbicides break down faster
when the soil is moist and warm.
2. A large proportion of a blackberry plant is
underground in the crown and root system.
Translocation of lethal quantities of herbicides
into these parts of the plant is essential to
kill the plant. Therefore, selection of the
most appropriate herbicide and application
technique is critical.
3. There are a number of techniques suitable
for applying herbicides for blackberry
management (see ‘Herbicide application
techniques’, p. 50). The most appropriate
technique to apply herbicides will vary
between sites, depending on accessibility,
associated vegetation, cost of application,
the resources available and proximity to
waterways.
4. The level of control with herbicides is often
variable and can be attributed to one or more
of the following:
• variation in herbicide application
• the timing of herbicide applications
• the condition of the plants being sprayed
• weather conditions at the time of spraying
• the age of the plant
• treatments before or following herbicide
application
• the plant species
• the quality of the water used
• the type and rate of herbicide used.
Monitoring the success of herbicide
applications is very important to identify any
areas that require follow-up treatment.
1. Most herbicides used in blackberry
management are absorbed through the foliage
or stems and leaves. However, some of the
herbicides are also absorbed through the
roots and can remain active in the soil (i.e. are
residual) for some time (see ‘Type and rate of
herbicide used’, p. 43).
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