Mimosa pigra

• This erect, branched shrub grows up to 6m tall.
• Taproots branch and extend 1–2m deep.
• Thorns are rose-like and 5–10mm long.
• Leaves are bright green, fern-like and 20–25cm long.
• The central leaf stalk is prickly.
• Flowers are round, fluffy, pink and 1–2cm wide.
• Each flower produces a cluster of 10–20 thickly haired seed pods, each 6–8cm long.
• Each pod contains 20–25 oblong-shaped seeds that are 4–5mm long and 2mm wide.

3D model

• View the 3D model to help you identify this plant. You can magnify the image and manipulate the view to inspect the plant from every angle.

• Favours a wet to dry tropical climate, in areas with more than 750mm annual rainfall and higher temperatures.
• May also pose problems in wetlands and around dams and waterways in areas with less than 750mm annual rainfall.
• Survives on a range of soil types and is found in moist situations such as floodplains and riverbanks.

• Mimosa pigra has been found at Peter Faust Dam near Proserpine.
• Visit Weeds Australia and click on the distribution tab to view the distribution map.

• Germinates when floodwaters recede in the dry season, or in the wet season between November and March in the Northern Territory.
• Flowering can occur as little as 2 months after germination and podding as early as 5 months after germination.
• Main flowering occurs from January to May and podding from March to July. Further flowering can occur at other times if moisture is sufficient.
• Seeding occurs approximately 3 to 6 weeks after the flower bud forms.

Environmental

• Grows aggressively.
• Forms dense, impenetrable thickets, 3–6m tall.
• Establishes along riverbanks, and encroaches into billabongs and out onto drier floodplains.

Economic

• Smothers pastures, reducing available grazing area, and affects stock mustering.

Social

• Affects access to water for recreation.

• Spread by floods, tidal movement, machinery, vehicles and boats.
• Also spread by seeds sticking to clothes, hair and animals.

• Find out how farmers can prevent weed spread.
• Find out how gardeners and outdoor enthusiasts can prevent weed spread.

• Before undertaking any preventative or control actions, contact us online, by phone or in person.

Biological control

• In the Northern Territory, 13 biological control agents have been released.
• In Queensland, 3 of these—the insects Neurostrota gunniella, Malacorhinus irregularis and Coelocephalapion pigrae—were released in 2006 but failed to establish.

• Mimosa pigra is a category 2, 3, 4 and 5 restricted invasive plant under the Biosecurity Act 2014. You must not:
  • give it away
  • sell it
  • release it into the environment.

If you do any of these, penalties may apply.

• You must take all reasonable and practical measures that are under your control to minimise the biosecurity risks associated with dealing with Mimosa pigra. This is part of your general biosecurity obligation.
• You must report all sightings with 24 hours using 1 of these methods:
  • Report online.
  • Phone Biosecurity Queensland on 13 25 23.
  • Phone the Exotic Plant Pest Hotline on 1800 084 881.
• Each local government agency must have a biosecurity plan that covers invasive plants in its area. This plan may include actions to be taken on Mimosa pigra. Some of these actions may be required under local laws. Contact your local government for more information.