Perennial biofuel crops such as miscanthus, whose high yields have led them to be considered an eventual alternative to corn in producing ethanol, are now shown to have another beneficial characteristic -- the ability to reduce the escape of nitrogen in the environment. In a 4-year study that compared miscanthus, switchgrass, and mixed prairie species to typical corn-corn-soybean rotations, each of the perennial crops were highly efficient at reducing nitrogen losses, with miscanthus having the greatest yield.