By Matt Styslinger
The wild African black plum (vitex doniana) has great potential as a by-product of a revered—and useful—native tree. The greatest economic potential of the vitex trees probably lies in the wood and leaves. But black plums support diets and incomes throughout the life of the tree.
Black plums are common across tropical sub-Saharan Africa’s coastal savannas and savanna woodlands. The black plum tree is not domesticated, but it is widely utilized and protected and is often found at the center of West African villages. There is little scientific data on the tree, but African horticulturalists, livestock keepers, and foresters stand to benefit from in-depth research and commercial development.
The olive-shaped fruit has a sweet, prune-like taste with a hint of chocolate. It is believed to have high levels of vitamins A & B. They are usually eaten as snacks, either fresh or dried. Children are especially fond of collecting and snacking on the black plums. But during food shortages, the fruit becomes of vital nutritional and economic importance. In these periods it is sometimes cooked before eating. They are usually collected from the ground rather than picked from the tree and are sold in local markets when the fruits are abundant.
The fruit makes good quality jellies and jams as well as a black molasses. A beverage similar in flavor to coffee is also made from roasted fruits. Young, leafy shoots from the tree are picked, boiled, seasoned, and eaten like spinach.
In addition to its edibility, the black plum tree supports rural micro-economies and environmental health. The leaves, pods, and seeds make excellent fodder for goats, sheep, and cattle. The trees are especially utilized for livestock fodder during dry seasons and drought. Its long roots can reach deep groundwater pockets, which keeps its leaves green much longer than the grasses that livestock usually depends on.
Beekeepers value the tree as a base for their beehives. Abundant white flowers attract bees, and beekeepers like to hang hives in the branches or in a hollowed out trunk of a black plum tree.
The tree is used for a variety of medicinal purposes as well. The edible parts of the tree are traditionally prescribed for anemia, due to high iron and potassium content. Leaves are also eaten to treat dysentery. Bark extracts are believed to be useful treatments for jaundice, toothaches, leprosy, and other skin ailments. Some traditions use the bark to improve fertility in women.
The black plum is useful in agroforestry and organic farming. It is nitrogen fixing, meaning it adds nitrogen to the soils it grows in. Whether the tree is growing throughout the field or along boundaries, crops can benefit from natural soil nutrients. Shade from the tree can protect from over-exposure to the tropical sun. Leaves from the tree are also used as nutrient-rich mulch.
The tree also promotes natural biodiversity. The fruit and leaves support wildlife. Its nitrogen fixing abilities encourage soil health and its deep roots protect soils from erosion, benefitting other plant life. In this way, it could be utilized for rebuilding degraded native ecosystems.
Timber harvested from black plum trees is medium hard and is similar to teak. It is termite resistant, making it favored as a building material. It is known to be used for making furniture, boats, chairs, and drums and is good for carving. It also makes quality firewood and charcoal.
To read more about crops indigenous to Africa see: Safou: the “Butterfruit” , Traditional Food Crops Provide Community Resilience in Face of Climate Change, Monkey Oranges: Mouthwatering Potential, The Green Gold of Africa, Fonio: Africa’s Oldest Cereal Needs More Attention, The Locust Bean: An Answer to Africa’s Greatest Needs in One Tree, and Lablab: The Bountiful, Beautiful Legume, Moringa: The Giving Tree, Black-eyed Peas to the Rescue.
Matt Styslinger is a research intern with the Nourishing the Planet project.
- Black-eyed Peas to the Rescue
- Marula: Food, Function, and Sustainable Development
- African Eggplant: The Fruit that is Enjoyed as a Vegetable
- Monkey Oranges: Mouthwatering Potential
- Ebony: The African Persimmon
- The Future of Our Food System: Our Changing Climate and Food Availability
- It’s About More Than Trees at the World Agroforestry Centre
- Innovation of the Week: Homegrown Solutions to Alleviating Hunger and Poverty