Forests can be cut down for a variety of reasons – expanding cities or mining, for example, but the biggest driver of deforestation is agriculture. In Latin America it accounts for 90% of deforestation – clearing the forest for planting cash crops or raising livestock. This is understandable, especially when it is for subsistence farming, but it doesn’t have to be this way. It is possible to farm the forest and keep the trees.
That’s the philosophy behind layer farming, a technique based around multiple crops at different levels, using the full height of a forest. It’s a farming method that Practical Action have been encouraging in Peru in the ‘cloud forests’ at the source of the Amazon. Their model consists of five layered crops. At the bottom is fast-growing cassava, which grows in the shade and also conditions the soil. Above that is coffee bushes, then bananas, with their wide leaves shading the coffee. Next up is a native tree called inga, which has nutritious oily seeds. All of these grow under the canopy of cedar, 20 – 40 metres tall.
The beauty of the system is that it has short, medium and long term yields. Farmers can get a harvest of cassava in the first year, so there is no long wait for it to start producing. The coffee plants take four years to mature, and then provide a cash crop. The inga trees reach 10m tall in that time, shading the coffee and giving it a higher value as shade-grown beans. Bananas provide fruit, or you can swap in laurel at that layer if you need timber – it matures at 12 years. The cedar is the long term crop, a gift to future generations. It doesn’t mature for 100 years, when it can be felled as a high value timber.
This is just the sort of win-win development that I get excited about. Small scale farmers increase their yields and are lifted out of poverty. Soil and biodiversity is preserved. Land is stewarded for the future and the forests are left standing as a carbon sink.
Practical Action have trained 5,000 Peruvian farmers in the technique so far, safeguarding 10,000 hectares of forest. You can make a donation here.
Agroforestry isn’t just for Peru either. My parents are experimenting with forest gardening on their little nature reserve in Wales. You can find out more about how it works in a British context from the Agroforestry Research Trust.