Scaling up the Effect of Intercropping with Native Evergreen Woody Shrubs from Plot to Region in the Peanut Basin, Senegal.

In this study we investigate how farmers can increase crop productivity by capitalizing on the evolutionary adaptation of native shrubs to the harsh Sudano-Sahelian environment. We focused on the physical mechanisms at work in the system that can lead to more robust yields. Over the last two years data were collected on soil moisture and temperature, climate, water retention, infiltration rates, crop yield parameters, handheld normalized difference vegetation index (NDVI), leaf water potential, and leaf area index (LAI). In 2012 and 2013 at these long-term research plots there was significantly higher yield of both peanut and millet in shrub-associated plots compared to sole crop plots. In an attempt to scale up the study from long-term managed research plots to the larger region, the fields of three farmers in the zones of Nioro Du Rip and Thies, Senegal were monitored with handheld NDVI and soil moisture and yield were quantified. Shrub-associated plants had significantly higher yields (t-test, p<0.1) than plants that were harvested at a distance of greater than 5m from the shrubs and there was a strong correlation between crop yield and NDVI just before flowering. These findings build on work that was completed in 2004 in the region, but attempt to scale up the study from the managed plot to farmer-managed fields. Adoption of this agro-forestry technique is possible over wide swaths of the Sahel even with the limited resources that local subsistence farmers possess.