Erect, annual herb <1m high. Stems have purple blotches, & covered in short, upward pointing hairs. Roughly textured, dark green leaves have minute bristles, hairs & prominent veins. Inconspicuous flowers (Jan-Mar) clustered at ends of branches. Hard, brown, woody burs with numerous spikes & hooks each contain two seeds.
Pasture, open areas, roadsides. Prefers warm conditions on disturbed & fertile soil.
Seed dispersed by clinging to wool, fur, clothing & machinery. Also in agricultural seeds & gravel. Air pockets on spines of burs aids dispersal by water.
Seeds are poisonous to stock, particularly pigs & cattle. Burs contaminate wool, compete with pasture species & can carry some fungal diseases capable of infecting horticultural plants
Plants must be treated before any burs are formed to ensure seeding is prevented. Re-sowing after plant removal is essential.
1. Pull or grub out scattered plants.
2. Mow or rotary slash before burs form.
Caution: when using any herbicide or pesticide PLEASE READ THE LABEL THOROUGHLY to ensure that all instructions and safety requirements are followed.