Letestua durissima

Letestua durissima is a large evergreen tree in the Sapotaceae family. It comes from Gabon and the Republic of Congo. Its native home is the wet rainforest of west-central tropical Africa. Local names include Kong-Afane in Gabon and Congotali in Congo. Sources describe a wild timber tree, with little known about cultivation. It is the only recognized species in its genus.

Published size figures give a height of 131 feet [40 metres]. Some trees reach 164 feet [50 metres]. PFAF lists a spread of 98 feet [30 metres]. These figures do not establish a usual garden size. The trunk grows straight and round. It can reach almost 8 feet [2.4 metres] across. Some trunks lack branches for 131 feet [40 metres]. Deep grooves or steep buttresses may form at the base. The supplied accounts give no details about flowers or fruit.

PFAF describes fast growth and a need for full sun. It lists moist soil with good drainage as suitable. The tree can grow in sand, loam, or clay. Mildly acid to neutral soil suits it. PFAF gives USDA zones 10–12 as its hardiness range. Fresh seed offers a way to raise new trees. Sources report germination within seven to 30 days. Nearly all fresh seeds may sprout under suitable conditions. Detailed growing methods remain unknown in the supplied accounts.

The tree's main value lies in its dense, hard timber. People harvest wild trees and trade some wood abroad. Uses include heavy building work, floors, boats, poles, and farm tools. The inner wood starts dark reddish brown and turns chestnut with age. A clear boundary separates it from the pale brown outer wood. The grain tends to run straight but can interlock. The wood has a fine to medium texture. It is strong, stiff, and durable, including in damp settings.

Working the timber poses several problems. Its high silica content blunts saws, and its dust can irritate. The wood dries slowly and may warp or crack. Once dry, it remains fairly stable. Termites seldom attack the timber, but marine borers require protective treatment. Lyctus borers do not attack the outer wood. These are timber traits, not evidence about pests of living trees. No edible uses are known. Traditional healers include a bark decoction in remedies for leprosy. This reported use does not establish its safety or effectiveness.