This project studies the effect of green mulch applications on nitrogen dynamics beneath cupuaçu (Theobroma grandiflorum) trees in agroforestry systems. Cupuaçu is an economically important crop in Amazônia, Brazil. It is typically cultivated on degraded soils, has shallow roots and low quality litter, therefore leguminous green mulch applications could increase cupuaçu production through increased soil fertility. This research is composed of two components: a greenhouse experiment and a field experiment. In the field, available nitrogen in the soil beneath cupuaçu trees was analyzed after gliricidia (Gliricidia sepium) prunings were applied . The greenhouse component compared litter decomposition among different combinations of cupuaçu, gliricidia and inga leaves and the effect of these litter combinations on nitrogen mineralization in the soil. My objective is to understand how nitrogen availability beneath cupuaçu trees is affected by application of gliricidia and inga prunings and whether cupuaçu litter decomposition and nutrient release is increased by the prunings.