|Botanical Name||Xanthium spinosum|
DescriptionAn erect, spined plant, annual, growing up to a metre. Spines on the stem are straight but those on the fruits are hooked, enabling seed dispersal in animal fur, wool etc. Leaf underside is covered with dense grey-white tomentum.
Where is it found?Pasture, wasteland, coastal areas, and especially spots where soil has been disturbed as this activates long-dormant seed if the land has been previously infested.
Why is it a problem?A strong invasive plant in pasture and open waste land. Seeds last many years in the soil and may germinate when soil is disturbed in apparently clean land.
How does it spread?This plant is well adapted for dispersal as the hooked spines on the burs cling firmly to the wool or fur of animals, to their tails and manes and to packs, bags, clothing and any fibrous material. The burs also contaminate seeds of summer crops such as maize and sorghum, as well as bird seed and poultry feed. Burs also float on water and are moved rapidly along watercourses.
How do I get rid of it?
Grub out isolated plants before they set seed.
Leave on ground if no seed set. Burn at high temperatures if burs have formed.
Early control is essential in order to prevent the formation of burs.
(a) Isolated incidences: grub out plants before they flower and set seed or spray with an appropriate herbicide.
(b) Larger areas: spray with an appropriate herbicide before the plants set seed. Use one of the following herbicides:
(i) Tordon Gold Knapsack - 120mls to 10 litres water. Gunspray - 500mls to 100mls water.