By Janeen Madan
The locust bean’s name might seem deceiving – while only distantly related to beans, it is actually a tree. It is indigenous to the savannah regions of Africa, and most commonly found in the band stretching from Senegal to Uganda. The fruit pulp and seed extracts provide nutritious ingredients for traditional soups, sweetmeats and condiments across West Africa.
The locust bean is also extremely hardy; it is well suited to a wide range of soils, it survives fires, thrives in semiarid tropical climates, and has a low susceptibility to pests and diseases. The tree has a wide-reaching crown and can grow more than 20 meters tall. Often, people climb all the way to the top to pick the fruit – long pods, containing small seeds and a sweet edible pulp, that can grow as long as your forearm.
The sugary pulp can be eaten raw, used in traditional sweetmeats or mixed with water to make a refreshing drink. Given its sweet taste, children love it, and because it keeps well for days, it is also popular among travelers.
While the pulp makes for a good energy snack, the seeds are the plant’s most sought after product. Rich in protein, starch, fiber, sugar, and fat, as well as vitamins and minerals, such as calcium and iron, the seeds are about as nutritionally balanced a food as you can find. Because the pods mature during “the hunger season,” when most other vegetation has dried, the locust bean is a true lifesaver – it can be a source of emergency food with a high nutritional value.
The seeds are famous for their greasy extract, which is fermented and pressed into cakes or balls, known in West Africa as dawadawa. It has a pungent odor, often compared to that of aged cheese, and is used as a condiment or an ingredient for soup.
But the tree provides much more than just a source of nutritious food. Dawadawa’s widespread popularity makes the locust seed an important commercial item across West Africa. It is estimated that 200,000 tons of locust seeds are collected annually for dawadawa, just in northern Nigeria. The production and sale of dawadawa constitutes an important economic activity for women.
In addition, the locust tree provides much-needed shade and shelter from desert winds in thousands of villages across the continent. It is also beneficial to the underlying soil, which is improved by dung and urine of livestock that shelter under the tree’s shade. Its leaves are so rich in nitrogen and other minerals, that they are often collected as manure for soil improvement.
Most of the existing locust trees are found in the wild, and although the species’ response to horticulture remains unclear, its multiple benefits make it an ideal candidate to promote in other regions across the continent. The locust tree combines in a single species two of Africa’s greatest needs: food security and tree cover.
To learn more about crops indigenous to Africa, see: Moringa: The Giving Tree, Black-eyed Peas to the Rescue, The Taming of the Dika: West Africa’s Most Eligible Wild Tree, Amaranth: Food Production Without Attention, African Eggplant: The Fruit that is Enjoyed as Vegetable, The Little Legume That Could, A Little Crop That’s Come a Long Way, Many Good Reasons to Grow Teff and Native African Vegetables Could Help Solve Food Crises.
Janeen Madan is a research intern with the Nourishing the Planet project.