Maize weed control in tropical alley-cropping systems using foliage of different tree species as soil cover

Using foliage of woody species as soil cover (SC) in agroforestry systems is an agroecological technique which may help to confront great challenges to food production, including conservation of soil moisture, provision of nutrients to the soil, and weed control. This study evaluated the effect of adding foliage of Leucaena leucocephala and Guazuma ulmifolia as SC on diversity, abundance, biomass, and potential for suppression of weeds. Eight treatments were established based on addition or not of foliage of woody species as SC to maize crop between alleys of the woody species. Richness, density, diversity, and production of weed biomass at 35, 65, and 95 days after germination of maize were recorded, and the potential for weed suppression was calculated. The study identified 47 weed species belonging to 18 families; no significant effect of addition of foliage on diversity and density of weeds was found. Production of biomass was significantly greater in the control treatment without woody species or SC than in the other treatments, while the greatest potential for suppression (40%) was found for the treatment with SC of foliage of both woody species. It was concluded that addition of foliage of L. leucocephala and G. ulmifolia as SC reduces weed biomass, increasing potential for weed suppression. Therefore, use of foliage of these species in alley cropping agroforestry systems contributes to weed control.