A Decision Tool for Buffel Grass Control
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FACT SHEET Buffel grass is one of the greatest environmental weed threats to the ecosystems of arid and semi-arid South Australia. It is recognised as a transformer species through competition with native plants, its ability to alter fire regimes and the resulting impact on plant and animal communities. Buffel grass also presents an increased fire risk to human safety and infrastructure assets. This fact sheet assists land managers in deciding the appropriate action for controlling buffel grass infestations. The decision support tree, illustrated overleaf, is intended to assist land managers select the appropriate herbicide and management action. The associated control calendar is intended to inform the appropriate timing for each of the management activities recommended over the buffel grass life cycle. What is Integrated Weed Management? Integrated weed management (IWM) is a term used to describe the long-term management of a weed using a combination of prevention and control techniques. In the rangelands, IWM helps achieve effective long- term control that encourages the regeneration of native plants and animals within the infested area. A successful buffel grass management plan should include: • correct identification and knowledge of the weed’s life cycle to inform the best management approach • ongoing surveillance to assist in the prioritisation of sites and early detection of new infestations for control • mapping and monitoring weed populations to measure the success of control activities • a control strategy that uses a combination of methods to control the weed population taking account of site characteristics. What herbicides can be used? Selecting the appropriate herbicide is determined by a number of factors. The size, density and location of a population, in addition to available resources and the situation in which the infestation occurs, will determine the appropriate herbicide. For example: • Flupropanate is a grass selective herbicide that is taken up by the roots of actively growing tussocks. It is residual in the soil for approximately two years and prevents new germinations. It is a very stable herbicide and can be stored for extended periods of time when mixed with water. • Large-scale high density infestations are practical to treat with flupropanate alone due to the significant seed bank already present on-site and the preference to encourage competition by native plants. • The use of flupropanate is allowed under the existing APVMA permit PER9792. For more information see the buffel grass control fact sheet on the Biosecurity SA webpage. • Granular flupropanate has the benefit of being grass selective and will be washed into the rootzone by rainfall. It is ideal for application on isolated outliers and in difficult terrain where access to water is a limitation. • Glyphosate is a non-selective fast-acting foliar herbicide that is compatible with flupropanate. It is preferable to treat small infestations and outliers with a mixture of glyphosate and flupropanate as this will prevent seed set and minimise the likelihood of new germinations. • BioWeed is an organically certified herbicide that has proven to be effective in killing buffel grass seed. BioWeed is a pine-oil formulation suitable for application on organic properties and small isolated populations, where it is desirable to prevent the likelihood of new populations arising from wind-blown seed. A Decision Tool for Buffel Grass Control
Transcript of A Decision Tool for Buffel Grass Control
FACT SHEETBuffel grass is one of the greatest environmental weed threats to the ecosystems of arid and semi-arid South Australia. It is recognised as a transformer species through competition with native plants, its ability to alter fire regimes and the resulting impact on plant and animal communities. Buffel grass also presents an increased fire risk to human safety and infrastructure assets.This fact sheet assists land managers in deciding the appropriate action for controlling buffel grass infestations. The decision support tree, illustrated overleaf, is intended to assist land managers select the appropriate herbicide and management action. The associated control calendar is intended to inform the appropriate timing for each of the management activities recommended over the buffel grass life cycle.
What is Integrated Weed Management?Integrated weed management (IWM) is a term used to describe the long-term management of a weed using a combination of prevention and control techniques. In the rangelands, IWM helps achieve effective long-term control that encourages the regeneration of native plants and animals within the infested area. A successful buffel grass management plan should include:• correct identification and knowledge of the weed’s life cycle to inform the best management approach• ongoing surveillance to assist in the prioritisation of sites and early detection of new infestations for
control• mapping and monitoring weed populations to measure the success of control activities• a control strategy that uses a combination of methods to control the weed population taking account of
site characteristics.
What herbicides can be used?Selecting the appropriate herbicide is determined by a number of factors. The size, density and location
of a population, in addition to available resources and the situation in which the infestation occurs, will determine the appropriate herbicide. For example:
• Flupropanate is a grass selective herbicide that is taken up by the roots of actively growing tussocks. It is residual in the soil for approximately two years and prevents new germinations. It is a very stable herbicide and can be stored for extended periods of time when mixed with water.
• Large-scale high density infestations are practical to treat with flupropanate alone due to the significant seed bank already present on-site and the preference to encourage competition by native plants.
• The use of flupropanate is allowed under the existing APVMA permit PER9792. For more information see the buffel grass control fact sheet on the Biosecurity SA webpage.
• Granular flupropanate has the benefit of being grass selective and will be washed into the rootzone by rainfall. It is ideal for application on isolated outliers and in difficult terrain where access to water is a limitation.
• Glyphosate is a non-selective fast-acting foliar herbicide that is compatible with flupropanate. It is preferable to treat small infestations and outliers with a mixture of glyphosate and flupropanate as this will prevent seed set and minimise the likelihood of new germinations.
• BioWeed is an organically certified herbicide that has proven to be effective in killing buffel grass seed. BioWeed is a pine-oil formulation suitable for application on organic properties and small isolated populations, where it is desirable to prevent the likelihood of new populations arising from wind-blown seed.
A Decision Tool for Buffel Grass Control
Follow-up after summer rain events
for new germinations (minimum of
Spot spray with Roundup
Biactive or BioWeed and
Biactive
Man
agem
ent A
ctio
n an
d Fo
llow
-up
Asse
ss S
itePr
iorit
ise
Infe
stat
ion
Infestation within 10 m of standing water?
Water and spray equipment available?
Significant number of native plants amongst the infestation?
Consider management zones and treat high priority infestations first
Water and spray equipment available?
Infestation in close proximity to road/rail/watercourse
or priority asset: High priorityIsolated outlier: High priority
Follow-up every
2 years for a minimum of 4
years after initial treatment
Follow-up surveillance and control should be carried out annually to treat plants missed and/or new germinations outside the treated area
Boomspray with
flupropanate or spot spray with Flupropanate/
Glyphosate mix
Follow-up after summer rain events
for new germinations (minimum of
Physical removal
Infestation within 10 m of standing water?
Follow-up every
2 years for a minimum of 4
years after initial treatment
Treatment with GP
Flupropanate
Decision Support Tree – Buffel Grass Infestation
YES
YES NO
YES YESNO NO
NO
Significant number of native plants amongst the infestation?
Consider management zones and treat high priority infestations first
Water and spray equipment available?
Infestation away from key introduction pathway
or priority asset: Medium priorityIsolated outlier: High priority Infestation beyond the capacity
of resources available: Low priority
Consider incorporating into future work plans and source additional resources
Follow-up surveillance and control should be carried out annually to treat plants missed and/or new germinations outside the treated area
Decision Support Tree – Buffel Grass Infestation
NO
Follow-up every
2 years for a minimum of 4
years after initial treatment
Boomspray or spot spray with Flupropanate/
Glyphosate mix
Infestation within 10 m of standing water?
Burn infestation
Infestation within 10 m of standing water?
Desirable and safe to burn (feasible to reduce biomass and protect assets or human safety)?
Wait until there is approximately 15 cm regrowth prior to herbicide
treatment
Follow-up after summer rain events
for new germinations (minimum of
Spot spray with Roundup
Biactive or BioWeed and
Biactive
YES
YES
NO
YES YESNO NO
Buffel Grass Control Calendar Spring Summer Autumn Winter Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul AugGerminationFlowering and seed formation Seed setBurn – In conjunction with relevant herbicide 1Spray with Flupropanate+Glyphosate 2Spray with Flupropanate 3 4Treat with Granular FlupropanateSpray with Glyphosate 5Spray with BioWeedPhysical removal 6
Note: The timing of different growth stages and treatments can vary significantly depending on seasonal conditions.Buffel grass has the ability to germinate and set seed in as little as six weeks. This control calendar is based on Arid South Australian conditions.
Usual growth season Optimum time for using the stated control method Potential growth season Control method under favourable seasons
1 Burning must be undertaken in conjunction with follow-up herbicide application. Allow 15 cm of regrowth prior to herbicide treatment for effective control.
2 Treatment with glyphosate/flupropanate after March will prevent seed set of current germinants but is unlikely to prevent new germinations and seed set.
3 Ideally spray flupropanate in early spring to allow sufficient rainfall and time for the herbicide to take effect (approximately three months).
4 Spraying flupropanate after March is unlikely to prevent new germinations, seed production and set.5 Spot spray at any time of the year that buffel grass is green and actively growing. Repeated treatment is required
following subsequent rainfall event.6 Physical removal is highly likely to promote new germinations therefore follow-up control is essential.
For Further InformationFor resources on identification, control and vehicle hygiene visit www.pir.sa.gov.au/buffel-grassFor buffel grass control advice contact your local Natural Resources SA office www.naturalresources.sa.gov.au/homeFor more information on herbicide rates visit pir.sa.gov.au/weedsFor more information on on-label registrations and off-label permits visit http://apvma.gov.au/For resources on integrated weed management visit, http://www.environment.gov.au/biodiversity/invasive/weeds/management/integrated.html
Acknowledgements: The banner image in this fact sheet has been kindly provided by Les Pullen, Coober Pedy Council.
The development of this fact sheet was funded through the Native Vegetation Councils Significant Environmental Benefits Grants Scheme.
Disclaimer: This publication is provided for the purpose of disseminating information relating to scientific and technical matters. The Government of South Australia does not accept liability for any loss and/or damage, including financial loss, resulting from the reliance upon any information, advice or recommendations contained in the publication. The contents of this publication should not necessarily be taken to represent the views of the participating organisations.
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