Bitterweed

• Annual herb up to 60cm tall, compact and bushy under favourable conditions.
• Stems are smooth and branching with numerous leaves.
• Leaves are smooth, narrow, thread-like, light green to grey-blue.
• Flowers are yellow, daisy-like, about 2cm in diameter.
• Unnoticed when competing with other plants, producing a single flower on plants as small as 5cm tall.

• Prefers open fields, roadsides and disturbed areas in subhumid, warm temperate and subtropical areas where annual rainfall does not exceed 1,000mm.

• Only known to exist at a single location near Mount Tarampa in the Lockyer Valley in South East Queensland.

• Flowers mostly over spring and summer.
• Scented flowers are pollinated by insects such as bees and butterflies.
• Mature seeds are non-dormant and germinate readily in sunlight.

Environmental

• Competes with native vegetation.

Economic

• Potential weed of pastures.
• Poisonous to stock, including sheep, horses and cattle.
• Taints milk of dairy cattle.

• Seeds in hay, silage and on vehicles.

• 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.

Physical control

• Hand-pull, ensuring entire root system is pulled up.

Herbicide control

• Broad-leaf herbicides such as 2,4-D or Grazon P+D® can be effective.

Biological control

• No known biological control agents.

• Bitterweed is a category 2, 3, 4 and 5 restricted invasive plant under the Biosecurity Act 2014. You must not:
  • move it
  • keep it
  • 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 bitterweed. This is part of your general biosecurity obligation.
• You must report any sightings within 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.
  • Contact your local government.
• Each local government must have a biosecurity plan that covers invasive plants in its area. This plan may include actions to be taken for bitterweed. Some of these actions may be required under local laws. Contact your local government for more information.