August 24th, 2009
Forests and farms don’t mix, according to conventional wisdom.
Farmers are often portrayed as the villains, slashing and burning trees to clear land for crops and wrecking forests from the Amazon to Indonesia (…not to mention Europe, where people cleared most forests thousands of years ago).
But a report today by the World Agroforestry Centre indicates that farms aren’t such enemies of trees as usually thought - it says tree canopies cover at least 10 percent of almost half the world’s farmland. That is a gigantic area the size of China, or Canada.
Ten percent doesn’t sound much but one common definition of a “forest” by the U.N.s’ Food and Agriculture Organisation is an area where tree canopies cover at least 10 percent. It excludes farmland or urban areas (– otherwise your local supermarket car park might qualify if it’s got a few trees dotted around the tarmac).
Farmers sometimes keep trees as a backup if their main crops fail — with their deeper roots, trees producing fruit or nuts, for instance, can withstand droughts or floods better than many crops. Farmers also keep trees for uses such as a source of building materials, medicines or shade.
So trees are more common on farms than thought — and a home to a wider variety of insects or animals than a swathe of grassland, maize or wheat. They may also be a bigger store of the greenhouse gas carbon dioxide than expected, with a role in limiting global warming.
So have farmers got too bad a rap for deforestation?