Bidens pilosa flower NC4
Introduced, warm-season, annual to short-lived perennial, hairless to densely hairy herb to 1 m tall. Leaves are opposite, 6-12 cm long, 3-5 lobed and toothed. Flowerheads are in loose cymes or heads are solitary. Heads are 5-15 mm wide, with yellow central florets; white ray florets may be present. Fruit are 6-12 mm long, dark and linear; with 2-3 barbs at the tip. Flowering is year-round, but mainly from summer to autumn. A native of tropical America, it is a weed of disturbed areas, such as roadsides, pastures, maize, and sorghum. Sometimes incorrectly referred to as fleabane. An indicator of disturbance or low ground cover. Potentially toxic to sheep and cattle when plants accumulate high levels of nitrate (more likely on fertile sites). The risk to goats is low. Plants with normal nitrate levels are palatable and safe to graze. Burrs are a nuisance as they readily attached to clothing and fur. Aromatic oil in the plant has an offensive smell and can taint milk. Plants can be controlled by healthy vigorous pastures, grazing (goats preferred), chipping or hand pulling, slashing and herbicides.