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Crop swap: Afghan farmers are pulling up poppies for wheat.

Soaring food prices have led to violent riots and swift setbacks in the global fight against poverty this year. But in Afghanistan, which has been hit particularly hard by the spike in wheat prices, a silver lining to the food crisis is emerging. The high price of wheat might be accomplishing something the international drug war never could: convincing Afghan farmers, who supply 90 percent of the world’s opium, to abandon poppies for growing food.

Because wheat prices have nearly tripled in the past year, the price of bread for Afghans has risen dramatically. David Mansfield, an independent researcher who has studied Afghanistan’s opium market for nearly two decades, thinks that the price increase has made wheat a far more attractive crop to many poppy farmers. In 2007, a farmer could expect returns of about $320 per acre of wheat and $640 for an acre of poppy. But by this spring, the return on an acre of wheat had risen to $840 per acre, while poppy had fallen to $400 an acre.*

According to nearly 500 interviews Mansfield recently conducted with Afghan farmers, poppy yields this year have been much lower than expected, which suggests that farmers are planting more wheat in response to market pressures. “[P]eople said they were going to grow more poppy than they subsequently did,” Mansfield explains. He says that even farmers in the poppy capital of Helmand province may have torn up and replanted their...