African Redwood

It is a tree up to 20 m in height, with a short trunk, thick branches, and thick, peeling bark. The leaves are up to 40 cm long, compound with 7-13 leaflets, each leaflet about 10 cm long with a finely serrated margin, green above, silvery-haired below. The flowers are white to orange-buff or pinkish-red, produced in panicles 30–60 cm long.

It is generally found from 2000 to 3000 m elevation, in areas receiving 1000–1500 mm of rainfall annually. It can be found growing in mixed afromontane forest with Podocarpus, Afrocarpus, and other trees, and in drier afromontane forests and woodlands where Hagenia is dominant, or in mixed stands of Hagenia and Juniperus procera. It is often found near the upper limit of forest growth, giving way to giant heather zones above it.

Hagenia is used as a food plant by the larvae of some Lepidoptera species including turnip moth.

A drug obtained from the tree, known as Kousso, comprises the entire inflorescence kept in form by a band wound transversely round it. The active principle is koussin or kosin, C31H38O10, which is soluble in alcohol and alkalis, and may be given directly in doses or in an infusion of the coarsely powdered flowers. It is considered to be an effectual anthelmintic for tapeworm, Taenia solium.