The experiments of the Inga Foundation in Central America offer a realistic hope of sustainable agriculture in a rainforest environment.
Mike Hands, a Cambridge University-based ecologist (and farmer), has developed an alley cropping system based on the inga tree, a leguminous tree native to Central America, and is now working to get local farmers to use his system.
The problem: To feed their families, Central American farmers haven’t had much choice other than slash-and-burn agriculture. They clear rainforest trees, plant corn, quickly wear out the land and move on. Slash-and-burn can be sustainable, even positive, when there’s a lot of land and very few people – it mimics natural cycles of disturbance. With heavy population pressure, and especially with the thin rainforest soils, nutrients are quickly lost and the land can’t be restored before the farmer needs to plant there again. The result is ecological catastrophe. Huge carbon reserves are lost into the atmosphere as the rainforest is burned, and agricultural productivity declines – farmers say their yields are only 10 percent of what they used to be. Often invasive grasses take over the fields and prevent any productive use or restoration of the land. That sets up a downward spiral, as ever more rainforest trees must be cut down.
By planting their corn between rows of inga trees and using inga leaves and branches as mulch, the farmers can maintain permanent fertility in the same cornfield and prevent the growth of invasive grasses. The inga, which grows quickly and re-grows quickly after cutting, also provides edible fruit and wood for cooking. Rainforest trees can be replanted in ruined areas, and farmers may be able to plant other areas with fruit trees.
The foundation is supported by several funding organizations, but accepts donations from individuals as well.