African milkbush causes painful blistering and inflammation
Euphorbia tirucalli (Euphorbiaceae)
Common names: Ngego, ngewu, nlembonlembo (nlembo = finger) (Kongo), Euphorbe effilée, tirucalli (Fr), finger tree, finger euphorbia, African milkbush
A leafless succulent shrub with cylindrical shoots, 2 – 8 m tall. All parts produce copious white to yellowish latex. Dense clusters of flowers are produced at the ends of the branches. Fruit is an almost round capsule circa 8 mm × 8.5 mm, containing 3-seeds.
Often planted on graves, in markets and around homes in Kongo Central. Originally from Eastern tropical Africa, it has long since become naturalized in other parts of Africa, including South Africa and the Indian Ocean islands.
Usually grown from stem or root cuttings, it establishes quickly on almost any soil. Cuttings should be at least 10 cm long and should be left to dry for at least 24 hours before planting. For hedges use cuttings up to 1 m long. When grown as a fuel crop, cuttings can be planted very densely.
Euphorbia tirucalli may be coppiced, trimmed and top-pruned to establish a hedge.
The plant is widely naturalized and planted as a hedge throughout the tropics and subtropics. In Kongo Central a few drops of the latex are used as a strong and sometimes dangerous purgative. Coagulated and dried, a pinch is taken for the same purpose with palm wine.
In higher dose it is used as an ordeal poison and often results in death. It causes painful blistering and inflammation and may cause blindness if it comes into contact with the eyes.
The latex is externally applied to warts, wounds and for skin complaints. The latex is also used as a fly repellent in West Africa and a mosquito and termite repellent in Tanzania. In India the latex is used as an insecticide. The latex is very irritating to the skin and mucosa.
Gillet & Pâque 1910, Gillet 1927, Renier 1948, Daeleman & Pauwels 1983, Pauwels 1993, Grace 2008
All photos in this article © Barbara Hoelzl