Plantinvasivekruger - Asteraceae - Bidens pilosa L.

BIDPI

Asteraceae

Bidens pilosa L.

Bidens - refers to seed.
pilosa - pilose means hairy.

B. pilosa is a an erect, herbaceous plant. It is much branched, with a strong odor. The stem is reddish brown in color, is ribbed and has four faces. The angles have small hairs. The leaves are soft, light green. They are opposite and arranged crosswise in pairs. The blade is deeply cut into three to five segments whose edge is serrated. The petiole is long and lined with tiny white hairs. The flowers are grouped in globose heads at the terminal position or at the base of the leaves. Each head consists of a few white flowers spread on the periphery and numerous yellow flowers in the center. The inflorescence is surrounded by two rows of small green pieces shaped spatula . At maturity, the fruits of black balls are bristling with spines.

Cotyledons are elliptical to linear, petiolate, glabrous. 25 mm long and 5 mm wide.

Simple and opposite, long petiolate. The blade is serrated or deeply divided into three segments from the first pair of leaves. The margin is regularly toothed, both surfaces are smooth.

This is an erect plant, much branched, with a strong odour. Generally 20 to 60 cm, up to 1.5 m.

It has a deep taproot.

Quadrangular, hollow and more or less fluted. Smooth, green, although sometimes dark red.

Simple, opposite and decussate. Long petiolate. 2-6 cm. Deeply divided into 3 or 5 segments oval, narrowed in pseudo-petiole at the base. Margin segment is sharply toothed ( apiculate teeth ) and slightly pubescent. Upper and lower surfaces are glabrous. Veins pinnate.

Flowers are grouped in heads terminal and axillary from 8 mm high and 10 to 12 mm in diameter, long pedunculate (3-10 cm). Involucre of bracts spatulate, fused at the base and pubescent on the margin.

Outer flowers female, ligulate white to pale yellow. Inner flowers bisexual, tubular bright yellow.

The fruits are achenes, spindle-shaped, cross-section triangular and slightly grooved, ~0.5 to 1.3 cm long with 2 or 3 long spikes on top, with small thorns thoughtful.

This is an annual weed. It multiplies by seed. Seeds dispersed by animals, human, water and wind.

It is common to all crops and developed after clearing plots. It prefers moist areas.

Native to South America.

Distributed to the entire part of South Africa except in the North-West province.

It is widespread in the KNP.

Leaves are cooked as vegetables, browsed by game, stock and birds. Traditionally used to treat pains, rhumatism diarrhea and ear ailments.

It is an invasive weed, medium to high in vegetables and sugar cane when it grows in large numbers. It can interfere with the work of harvest.

Common widespread weed and extremely troublesome in crop fields.

Considered as an invasive weed, it has moderate impact on the ecosystems.

Easily controlled by post-emergence herbicides.

Common widespread weed and extremely troublesome in field crops.

-(Adventrop) Grard, P., T. Le Bourgeois and H. Merlier (2010). Adventrop V.1.5 Les adventices d'Afrique soudano-sahélienne. Montpellier, France, Cirad.
-(AdventOI) Le Bourgeois, T., A. Carrara, M. Dodet, W. Dogley, A. Gaungoo, P. Grard, Y. Ibrahim, E. Jeuffrault, G. Lebreton, P. Poilecot, J. Prosperi, J. A. Randriamampianina, A. P. Andrianaivo and F. Théveny (2008). Advent-OI : Principales adventices des îles du sud-ouest de l'Océan Indien. Cirad. Montpellier, France, Cirad.
-(AdvenPac) Blanfort, V., F. Desmoulins, J. Prosperi, T. Le Bourgeois, R. Guiglion and P. Grard (2010). AdvenPaC V.1.0 : Adventices et plantes à conflit d'intérêt des Pâturages de Nouvelle-Calédonie. Montpellier, France, IAC, Cirad.

http://idao.cirad.fr/SpecieSheet?sheet=adventoi/especes/b/bidpi/bidpi_fr.html