Karité (Vitellaria paradoxa) and Néré (Parkia biglobosa) associated with Crops in South Mali

background

This study analyzes the growing conditions of agricultural crops (cotton, sorghum, and pearl millet) under the common African savanna agroforestry trees Parkia biglobosa (karité) and Vitellaria paradoxa (néré), the source of the cosmetic product shea butter.

Goals & Methods

To determine the species effects on soil conditions, the researchers conducted two primary studies. They first completed a tree/crop interfaced study in 3 observational sites. They then conducted a soil analysis during the growing season at each of the sites at one time. 

Conclusions & Takeaways

The researchers found that soil under the trees was slightly higher in organic matter and some minerals, but that this effect could mainly be explained as a local re-distribution of nutrients. Only the karité - cotton association showed no reduction in crop yields, while the others demonstrated reduction of approximately 60%, possibly due to 1) enhanced moisture and subsequent fungal attack on the crop, and/or 2) reduced light and nutrient availability. Tree pruning is a remedy to improve crop yields, but risks the reproductive potential of the tree.