Invasive weed found around Bundaberg
THE Starburr (Acanthospermum hispidum) is native to Central America, parts of the Caribbean, and tropical South America.
It is also widely invasive in other parts of the world including Africa, India, Sri Lanka, Thailand, Indonesia, Papua New Guinea, Hawaii and the southern parts of the USA.
It's widely invasive throughout northern and eastern Australia. It is found in a number of paddocks and bushland in the Bundaberg region. It is widespread in Queensland, parts of northern New South Wales, Victoria, the northern parts of the Northern Territory, in the Kimberley region in northern Western Australia and south-western Western Australia.
It's a weed of pastures, crops (pumpkins, melons, soybeans, sugar cane, peanuts and cotton), disturbed sites, roadsides and waste areas in the warmer (i.e. tropical, sub-tropical and semi-arid) climatic regions of northern Australia. It is also often very common along waterways and on floodplains. This species is also a host for a number of insect pests and viral diseases that attack crops.
Though this species is largely seen as a pest of agricultural crops and pastoral land in northern and eastern Australia, it is also regarded as an environmental weed in these areas where it can form mono species populations preventing other grass and herb species from growing.
It has also invaded national parks, where it causes significant environmental damage to natural ecosystems and small native animals with soft paws.
Starrburr is also ranked as a high priority weed by the Queensland government and a number of regional councils. It was also recently listed as a high priority environmental weed for control and eradication in two of Queensland's Natural Resource Management regions.
It can significantly reduce the productivity of native pastures but is generally not grazed by livestock. The prickles can cause face, eye, mouth and foot wounds to livestock and native animals. It is also known to be toxic to goats. The fruits are poisonous but stock losses are rare because the prickles deter stock from eating it.
Seed is mostly spread as a contaminant of grain crops, livestock fodder, in animal fur, wool, clothing, tyres, and on vehicles in mud or spaces.
An upright stiffly hairy low-growing, short-lived (annual) herbaceous plant growing 15-100 cm tall, but usually less than 50 cm in height.
Its leaves are stalkless, covered in stiff hairs, and borne in pairs along the stems.
Inconspicuous yellowish-green flowers are borne in the forks of the leaves near the top of the plant.
Its five sectioned fruit develop into 5-10 spiny wedge-shaped "seeds" which radiate outward and form a distinctive star-shaped 'burr'.
Herbicide applications are the easiest control method but footwear should be checked afterwards for burrs. Cultivation will only spread the weed and seeds. Soil disturbance should be avoided as that assist the weed spread.
It is possible to hand pull individual plants or small infestations by grabbing the plant close to the ground but thick gloves and long sleeve shirts and long trousers should be worn to avoid burrs. Check clothing after control methods to avoid spreading the weed. Pulled plants should be bagged and left in the sun for 4 hot days to kill the seeds.
Ian Read can be contacted on 41599365, or email firstname.lastname@example.org for free weed presentations/workshops to landowners and community groups, or for weed identification.