Biofuels are being touted as the new panacea for climate problems. But because this fuel from plants is being introduced without much thought about wider implications, it's becoming a good idea

The United States is the world's leading producer of soy. However many U.S. farmers are shifting from soy to corn in order to qualify for generous government subsidies intended to promote biofuel production. The rising price for soy has important consequences for Amazonian forests and savanna woodlands. (Letters)