Senna petersiana aka Eared Senna

Senna petersiana is a shrub or small tree. It belongs to Fabaceae, the pea family. Its native range runs from Cameroon east to Ethiopia. It reaches south to South Africa. Kew also lists it as native to Madagascar. It grows in the tropics, where some seasons are dry. Wild plants grow at rainforest edges and beside rivers in forests. They grow in woods whose trees shed their leaves, too. Other sites include evergreen scrub near coasts and grassland with trees. Records place it up to about 8,200 feet [2,500 metres].

The plant has a round crown with few or many branches. Useful Tropical Plants lists about 26 feet [8 metres] in height. Its full account gives a top height of 39 feet [12 metres]. People grow it for its looks at times. They also gather plants from the wild. The account gives no details of its leaves or bark. It shows plants in flower but gives no bloom season. Its fruits are seedpods that hold sweet pulp.

People eat this sweet pulp raw. Children in its native range eat it, too. People also soak and boil the pods to make gruel. They use seeds and fruits to make a drink with alcohol. These are local food uses, not claims of safe, unrestricted use. Useful Tropical Plants lists no known hazards. Yet it also notes compounds with a strong laxative effect. These can cause the bowels to empty. Leaves, bark, roots, and pods contain anthraquinone glycosides.

In folk medicine, people use roots to purge the bowels. They use fresh leaves less often for this purpose. Uses on record include constipation, stomach pain, and intestinal worms. Records from southern Africa also list malaria and schistosomiasis. They list gonorrhoea and syphilis, too. These uses do not prove that the plant treats these ills. Seeds contain luteolin, a flavone studied for effects against microbes. Lab tests found some effects against viruses from seed extracts and luteolin. Luteolin also showed effects against bacteria. People use the light wood for tool handles and fuel.

The seeds' hard coat can slow sprouting. Scraping the coat and soaking seeds may help them sprout. The source describes soaking seeds in warm water. It also describes careful nicks in seeds that have not swollen. Do not harm the embryo when nicking the coat. Reports say this species lacks bacteria that fix nitrogen. Many other plants in its family have these partners.