What does it look like?
Noogoora bur is a fast-growing summer annual that can reach heights of 2m - 2.5m. Its is named for the clusters of distinctive, egg-shaped burs that contain seeds. The burs are 10-25mm long and covered in hooked spines with two thick spines at the tip. The plant can grow with a single stem or as a multi-stemmed bush. The leaves are dark green above, paler below and irregularly lobed with purplish veins. The stems are rough to the touch and streaked with purple.
Noogoora bur favours fertile soils and is often found close to water. It usually grows on arable land and in paddocks but it is also found on disturbed ground, stream banks, and other riparian areas.
Why is it a problem?
Noogoora bur contains chemicals that can impede the growth and germination of neighbouring plants. It produces large quantities of seeds that germinate into a fast growing and highly competitive weed that can cause significant losses in many crops.A single plant can produce 10,000 seeds, which are contained inside burs. The seeds may remain dormant in the soil for many years. The seeds are contained in the burs which spread by attaching to animals, clothing and agricultural machinery. They may also be spread in seed, feed,
gravel and soil and float, so can be spread by water. Seed may remain dormant in the soil for many years.