Improving yields by integrating a diversity of shrubs or trees into crop fields

This poster is available for download and printing, intended for use in workshops with farmers to facilitate the reflections and exchange of experiences related to the advantages of integrating trees into crop fields.

The poster illustrates key reasons why integrating trees and shrubs with cereal crops in Sahelian landscapes is a promising approach:

Farmers in the Sahel region are increasingly challenged by unpredictable rainfall, prolonged drought, and intensified soil degradation. These issues are leading to lower yields of important food crops, such as millet and sorghum.

The Sustain Sahel project has shown that combining sorghum and millet with local shrubs called Guiera and Piliostigma, as well as with a local tree called Faidherbia Albida in fields, has beneficial effects. This finding is supported by several studies. Trees and shrubs infiltrate rainwater underground, storing it and making it available to crops during dry periods. They also provide habitat for numerous soil organisms, such as earthworms, which improve soil structure and facilitate crop growth. Pruning trees and shrubs and depositing their leaves on the field as mulch provides food for beneficial soil organisms. In turn, these organisms provide essential nutrients to crops and support their healthy growth.

These beneficial effects become even more critical when faced with the effects of climate change, such as drought. For example, the Faidherbia albida tree, as shown in one of our studies, has demonstrated its ability to buffer rainfall shortages in the Sahel region (Dauphin-Clermont et al., 2023).

On the other hand, if there are very few trees and shrubs in a field, water infiltration during the rains will be low, and evaporation will be rapid. Moreover, the absence of root systems to hold the soil in place allows the wind to blow the subsoil away, leading to erosion. Finally, the soil lacks organic matter and microorganisms. This combination of factors will result in low crop yields and ongoing soil degradation.