Noogoora burr is a short-lived, usually annual, shrub that is often abundant after spring and summer floods. It typically grows to around 1 m but may grow to around 2.5 m under ideal conditions and in the absence of a commonly-occurring leaf and stem rust and stem-boring and stem-galling insects.
The stems of the plant are rough to the touch, and feature short bristly hairs along its length. The leaves are usually a darker green towards the tips, and get paler as they get closer to the stalk.
The leaves are covered in small bristles and are coarsely toothed around the edges, with 3 prominent reddish veins extending to each of the 3 lobes.
The burrs themselves grow typically to around 7–25 mm long and are covered in hooked spines.
Each burr contains two seeds. Seedlings are poisonous to stock and may cause losses if eaten in sufficient quantities and the burrs are a costly contaminant in wool. Noogoora burr is a significant competitor in pastures and can be a serious weed in summer crops.
Controlling Noogoora Burr
When the infestation is small, Noogoora Burr can be removed by hand, ensuring the entire taproot is removed and disposed of by burning to prevent regrowth. Cultivation can be effective as long as it is performed before flowing.
For more extensive we recommend the use of Starane™ Advanced Herbicide as a foliar spray at a rate of 0.45mL/1L of water.
Herbicides for control of Noogoora Burr
# Note: Preferred product option in bold. * Consult label for details of growth stage and use, especially where range of rates is given.