A small woody-based shrub or herb with purple pea-like flowers, common on waste ground and roadsides.
Purple tephrosia (Tephrosia purpurea, family Fabaceae) is an upright or spreading herb, annual or living a few years, sometimes bushy, usually 40 to 80 cm tall and rarely up to 1.5 metres. It is gathered from the wild for a range of traditional medicines and is also grown as a green manure. It carries nitrogen-fixing bacteria in nodules on its roots, and when dug into the soil it adds humus and improves the soil's structure.
The plant contains rotenoids such as tephrosine, which stun fish, and its pounded leaves are used to catch fish; the stunned fish remain safe to eat. These compounds are only mildly toxic to people and other mammals, though deliberately swallowing them can be fatal, but they are very toxic to insects and fish, and they break down in sunlight within about six days. The species is probably native to the Indian subcontinent and China and is now naturalised throughout the tropics, in grassy fields, thickets, waste places and along roadsides, mostly below 400 metres. It prefers dry, gravelly, rocky or sandy soils, tolerates saline soils, roots deeply, and produces plenty of seed, building up a large seed bank in the soil.
Source: Useful Tropical Plants database (Fern, K.).
Roots, leaves, and seeds are used across Asia and Africa for liver, spleen, and kidney complaints, as a blood purifier, and for skin ailments; the plant also contains fish-stunning rotenoids and is traditionally used to stupefy fish for easy capture.
A hardy, self-seeding shrub of disturbed and waste ground, often found along roadsides and fallow fields.