Millettia laurentii aka Wenge

Millettia laurentii, or wenge, belongs to the pea family, Fabaceae. This tropical tree comes from west-central Africa. Its range includes Cameroon, Equatorial Guinea, Gabon, and the Central African Republic. It also grows in Congo and the Democratic Republic of the Congo. It lives in rainforest, riverbank woods, and tree savannah. Some sites drain well; others flood at regular intervals.

This deciduous tree has wide branches that droop. Garden size is about 82 feet (25 metres) tall. Its spread can reach 66 feet (20 metres). Forest trees often reach 98 feet (30 metres). Rare trees reach 164 feet (50 metres). The round trunk may bend slightly near its base. Small buttresses or flutes can form at ground level. Trunks can reach about 4 feet (1.2 metres) across. Some stay branch-free for 66 feet (20 metres), though most do not.

Purple-blue flowers cover the tree when it blooms. Bees visit them for nectar and pollinate the flowers. People plant wenge beside roads and in parks and gardens. Its broad form and flowers give it landscape value. Grow it in full sun, with moist soil that drains well. It accepts sandy, loamy, and clay soils. It also tolerates mildly acid, neutral, and mildly alkaline ground. PFAF lists USDA zones 10–12, so its hardiness range suits warm climates.

Wenge grows at a moderate rate. Root bacteria form nodules that help it use nitrogen from the air. Some of that nitrogen can support nearby plants. People plant it to restore woodland on former farmland. Stem cuttings also serve as living fences. Growers can raise new trees from seeds or cuttings. Its heavy, hard wood has value for furniture. Fresh-cut heartwood starts yellow, then turns dark brown with black streaks. Heavy timber harvest threatens wild trees across much of their range. Useful Tropical Plants cites an Endangered assessment from 1998.

No edible uses are known for this species. Traditional healers use the bark for many ailments. These include fever, skin complaints, diabetes, and liver problems. Such uses do not establish that home treatment is safe. People also use the bark to poison fish and arrows. Fine wood dust can trigger asthma and allergic skin reactions. A compound in the wood acts as a contact allergen. These hazards matter when cutting or working the timber.