Description:
Somewhat hairy and produce roots at their joints. Its paired leaves usually differ in size. Its greenish or greenish-yellow flowers are grouped together in small clusters (8-12 mm long) in the leaf forks. Some of the flower parts become hardened and form sharp prickles as they mature.
As A Soil Indicator:
ow calcium, High manganese. High Magnesium, High Iron, High Zinc, High Boron, High Chloride,  Little organic matter, anaerobic soil conditions, high moisture content, compacted, pour drainage
Life cycle:
Annual stems, perennial rootstock. Seeds germinate in spring and summer after rain and produce creeping stems and a stout rootstock over summer. Stems take root at the nodes forming a dense mat. Flowering occurs from March to April and the top growth dies in winter. New shoots emerge from the rootstock in spring.
Beneficial:
Fodder plant, moderately palatable when young.
Detrimental:
Forms competitive dense mats with prickly burrs that may injure the feet and mouths of stock and dogs. Readily dispersed by adhering to stock and tyres. Weed of Lucerne, orchards, turf, recreational areas, sale-yards, pastures, cultivated areas and roadsides. 
Toxicity:
May cause hay fever, dermatitis and asthma in some people. Toxic to stock but not usually eaten. Sheep will graze young plants without any apparent ill effect. Causes a skin ailment in cattle.

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