Mysore thorn, also known as wait-a-while, is an aggressive prickly shrub that forms dense thickets. It invades environmental areas, creek banks, roadsides, pastures and bushland.
Mysore thorn was originally planted in gardens as a hedge plant. It is now an environmental weed. Mysore thorn can affect the biodiversity of native bushland areas by out-competing and smothering native species. Its dense thickets can provide a harbour for feral animals, restrict the habitat available for native animals and inhibit access to water, roads and pasture. Invasion and establishment of exotic vines and scramblers has been identified as a key threatening process for many vulnerable and endangered species in NSW. Mysore thorn is one of the main species listed as a threat.
Mysore Thorn is a large evergreen shrub growing 2–4 m high, or up to 20 m high when climbing over supporting vegetation.
Mysore thorn is native to Japan, China, India and Malaysia. It is present in many countries around the world and is an invasive weed in New Zealand, the Dominican Republic, South Africa and Hawaii.
Mysore thorn is predominantly located along the south-eastern Queensland coast. Scattered infestations occur in some southern inland locations and along most of Queenslands coast line.
In New South Wales many localised infestations—which continue to spread—occur in the north coast region. Small, localised infestations are also present along the central coast of NSW.
Mysore thorn reproduces by seed, which may stay viable in the soil for up to 10 years. The seed is mainly dispersed by animals that feed on the fruit, such as rodents, birds and cattle. Seed pods float on water, spreading seeds downstream to new locations.
The branches of mysore thorn produce new roots when they come into contact with the ground, anchoring the plant into the soil. Plants will re-shoot vigorously when cut.
Mysore thorn flowers during winter and spring. Fruits are produced from August through to December.
Mysore thorn prefers humid coastal conditions in sub-tropical to tropical climates. Mysore thorn grows on a variety of soil types and will tolerate annual rainfalls from 300 to 3000 mm. It will often grow in disturbed areas, roadsides, pastures, creek banks, native grasslands and along the edges of bushlands and forests.
CABI invasive species compendium online data sheet. Caesalpinia decapetala (Mysore thorn). CABI Publishing 2011. www.cabi.org/ISC. Accessed August 2014.
Department of the Environment (2011). Weeds in Australia: Caesalpinia decapetala . Australian Government. www.environment.gov.au/biodiversity/invasive/weeds/identification/index.html. Accessed August 2014.
Hosking JR, Sainty GR, Jacobs SWL & Dellow JJ (in prep) The Australian WeedBOOK
Parsons, W.T. & Cuthbertson, E.G. (2001). Noxious weeds of Australia, CSIRO Publishing, Collingwood.
Richardson F.J., Richardson R.G. & Shepherd R.C.H. (2011). Weeds of the south-east: an identification guide for Australia. RG and FJ Richardson, Meredith, Victoria.
Any control activities for mysore thorn will need to be monitored and followed up with additional control measures as required.
Only recommended for small plants and seedlings that can be manually pulled or hoed from the ground. Take care to remove all of the roots. Larger plants and infestations are difficult to treat in this way. The thorny habit of mysore thorn and ability to rapidly re-shoot from cut stems, makes mechanical control challenging.
Treat when plants are actively growing and before flowering. In dense infestations, foliar applications repeated every 3–9 months will give the best results.
See Using herbicides for more information.
Metsulfuron-methyl 300 g/kg + Aminopyralid 375 g/kg
Rate: 20 g per 100 L of water and a wetting agent at 100 mL/100 L.
Comments: Thorough spray all the foliage and stems until wet. Suitable wetting agents: BS1000 Biodegradable surfactant, Chemwet 1000 Wetting Agent, Uptake Spraying Oil or Pulse Penetrant
Withholding period: Pastures - Grazing for meat production or cutting for animal feed: Do not graze for 56 days after application. See label for further details
Herbicide group: 2 (previously group B), Inhibition of acetolactate and/or acetohydroxyacid synthase (ALS, AHAS inhibitors) + 4 (previously group I), Disruptors of plant cell growth (Auxin mimics)
Resistance risk: High/Moderate
Metsulfuron-methyl 600 g/kg
Rate: 10 g per 100 L of water
Comments: Spray to thoroughly wet all foliage, but not to cause run off. Apply to actively growing plants before flowering. Add wetting agent.
Withholding period: Nil (recommended not to graze for 7 days before treatment and for 7 days after treatment to allow adequate chemical uptake in target weeds).
Herbicide group: 2 (previously group B), Inhibition of acetolactate and/or acetohydroxyacid synthase (ALS, AHAS inhibitors)
Resistance risk: High
Picloram 44.7 g/L + Aminopyralid 4.47 g/L
(Vigilant II ®)
Comments: Cut the stump then apply a 3–5 mm layer of gel for stems less than 20 mm diameter. Apply 5 mm layer on stems above 20 mm diameter .
Withholding period: Nil.
Herbicide group: 4 (previously group I), Disruptors of plant cell growth (Auxin mimics)
Resistance risk: Moderate
The content provided here is for information purposes only and is taken from the Biosecurity Act 2015 and its subordinate legislation, and the Regional Strategic Weed Management Plans (published by each Local Land Services region in NSW). It describes the state and regional priorities for weeds in New South Wales, Australia.
|All of NSW
|General Biosecurity Duty
All pest plants are regulated with a general biosecurity duty to prevent, eliminate or minimise any biosecurity risk they may pose. Any person who deals with any plant, who knows (or ought to know) of any biosecurity risk, has a duty to ensure the risk is prevented, eliminated or minimised, so far as is reasonably practicable.
Regional Recommended Measure* (for Regional Priority - Prevention)
The plant should be eradicated from the land and the land kept free of the plant. The plant should not be bought, sold, grown, carried or released into the environment.
Regional Recommended Measure* (for Regional Priority - Eradication)
Notify local control authority if found. Land managers should eradicate the plant from the land and keep the land free of the plant. A person should not deal with the plant, where dealings include but are not limited to buying, selling, growing, moving, carrying or releasing the plant.
Exclusion (eradication) zone: Bellingen Shire LGA, Clarence Valley LGA, Lord Howe Island, Port Macquarie-Hastings LGA. Core infestation (containment) zone: Ballina Shire LGA, Byron Shire LGA, Clarence Valley LGA, Coffs Harbour City LGA, Kempsey Shire LGA, Kyogle Shire LGA, Lismore City LGA, Nambucca Valley LGA, Richmond Valley LGA, Tweed Shire LGA.
Regional Recommended Measure* (for Regional Priority - Containment)
Whole of region: Land managers should mitigate the risk of the plant being introduced to their land. A person should not buy, sell, move, carry or release the plant into the environment. Exclusion zone: Notify local control authority if found. Land managers should eradicate the plant from the land and keep the land free of the plant. Core infestation: Land managers should mitigate spread of the plant from their land. Land managers should reduce the impact of the plant on assets of high economic, environmental and/or social value.
Containment zone: Wollongong Local Government Area. Exclusion zone: Whole of region except containment zone.
Regional Recommended Measure* (for Regional Priority - Containment)
Whole of region: Land managers mitigate the risk of new weeds being introduced to their land. A person should not deal with the plant, where dealings include but are not limited to buying, selling, growing, moving, carrying or releasing the plant. Within exclusion zone: Land managers should eradicate the plant from the land and keep the land free of the plant. Notify local control authority if found. Within containment zone: Land managers should reduce the impact of the plant on assets of high economic, environmental and/or social value. Land managers should mitigate spread of the plant from their land.
|*To see the Regional Strategic Weeds Management Plans containing demonstrated outcomes that fulfil the general biosecurity duty for this weed click here