Bitter weed

• 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 gray-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 Mt Tarampa in 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 our Customer Service Centre.

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.

• Bitter weed is a prohibited invasive plant under the Biosecurity Act 2014.
• You must not keep, move, give away, sell or release into the environment. Penalties may apply.
• You must not take any action reasonably likely to exacerbate the biosecurity threat posed by bitter weed.
• You must take any action that is reasonably likely to minimise the biosecurity threat posed by bitter weed.
• You must report all sightings to Biosecurity Queensland within 24 hours.