Inga Alley cropping

Inga edulis trees are planted in rows 4 m apart, grow fast to shade out weeds in approx. 2 years, are then pruned at 1.5m; leaf litter left on the ground creates a growing medium. Pruning can be repeated yearly; crops (typically maize, beans cassava etc) inside the alleys produce 3 to 15 times the weight of those planted outside. Farmers need support for 4-5 years to establish the system, then neighbours queue to get it. Inga edulis is a legume (nitrogen fixing) tree from Western Amazon, grown on all farms in Ecuador, but the system was unknown before we brought it there in 2016. The system provides full supply of firewood at pruning (protecting the forest); 1 Ha of Inga alleys replace at least 1Ha of slash and burn each year, so 20 Ha in 20 years. i.e each Ha of Inga saves between 5000 and 33000 Tonnes CO2 depending on forest quality.

Inga edulis trees are planted in rows 4 m apart, grow fast to shade out weeds in approx. 2 years, are then pruned at 1.5m; leaf litter left on the ground creates a growing medium. Pruning can be repeated yearly; crops (typically maize, beans cassava etc) inside the alleys produce 3 to 15 times the weight of those planted outside.
If the ground is sloping it is essential to plant along the contour to prevent erosion. The system is excellent erosion control when done properly. In Ecuador Inga seeds are sown directly into cleared ground (in Cameroon transplanted from nurseries). Weed control is very important until trees are at least 1.5m and making shade (6-9 months)