Bathurst burr

• Annual herb growing into erect, multi-branched plant up to 1m tall (usually 30–60cm).
• Leaves are dark green on upper surface, paler green underneath, up to 7cm long, usually 3-lobed, with cream mid-vein.
• Stems are branched, with one or two 3-pronged yellow spines at base of each leaf stalk.
• Flowers are creamy green, small, developing into straw-coloured burrs.
• Burrs are 1–1.5cm long, with numerous yellow-hooked spines.
• Each burr contains 2 seeds.

• Prefers drier areas such as well-drained contour banks and lighter soils.
• Occurs along roadsides, old cultivation paddocks and irrigated pastures or watercourses.

• Occurs in Southern, Western and Central Queensland but seldom in tropics.

• Germinates late spring to early summer.
• Produces burrs in February and dies in early winter.
• Seeds can germinate out of season.

Economic

• Contaminates wool, increasing processing costs.
• Competes with summer crops.
• Hosts fungal diseases that can poison stock.
• Seeds are poisonous to domestic stock animals.

• Burrs attach to animals, clothing, shoes etc, easily dispersing seed.
• Burrs float and can spread along watercourses.

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

Physical control

• Cultivation is effective in seedling stage.

Herbicide control

• Spraying with herbicides is effective, especially on young plants before burrs form.
• Read the Bathurst burr fact sheet (PDF, 3.1MB) for herbicide control and application rates.

Biological control

• Bathurst burr seed-fly (Euaresta bullans) and rust Puccinia xanthii may have limited effectiveness.

• Bathurst burr is not a prohibited or restricted invasive plant under the Biosecurity Act 2014. However, by law, everyone has a general biosecurity obligation (GBO) to take reasonable and practical steps to minimise the risks associated with invasive plants under their control.
• Local governments must have a biosecurity plan that covers invasive plants in their area. This plan may include actions to be taken on Bathurst burr. Some of these actions may be required under local laws. Contact your local government for more information.