Exploiting the Potential of Indigenous Agroforestry Trees: Parkia biglobosa and Vitellaria paradoxa in Sub-Saharan Africa

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This article reviews the agroforestry potential of two native African savanna trees, Parkia biglobosa (locust bean) and Vitellaria paradoxa (shea).

Conclusions & Takeaways

Parkia biglobosa, known locally as néré, is a tree used in savanna agroforestry systems for oil, spices, edible seeds, and medicine; it is also a legume and grows well in association with other crops, as it can enhance soil fertility. Studies have found that this species has high genetic variation across a large geographic distribution in the Sahel zone of Africa. It is most commonly pollinated by bats. Vitellaria paradoxa is known locally as karaté, and is popular for the high oil content in its seeds, which can be collected from wild trees in addition to being cultivated and exported for cosmetics (shea butter). It replaces oil palm in dryer savanna regions.  Vitellaria paradoxa is bee pollinated, but may be pollinator limited, as natural reproduction is low in many sites. Both of these species are diminishing in numbers- indigenous parkland agroforestry users sometimes do not have tenure, so they are not incentivized to plant. Agroforestry plantings works with some crops, but reduces yields of light demanding sorghum and millet. Hand pollination can promote regeneration, but seed reproduction is slow and difficult because fruits and seeds are harvested. Vegetative reproduction is possible with cuttings, tissue culture, air layering, and grafting techniques.