Seed and biotechnology companies are developing new technologies that will genetically alter certain crops for use in ethanol and other biofuels, The New York Times reports. Genetically engineered corn and switch grass can be designed to convert themselves into ethanol by breaking down the plant’s cellulose and starch into sugar, which can be fermented into ethanol. Environmentalists, however, worry that altered plants would cross-pollinate in the wild. This may result in structurally weakened plants with very little lignin, a substance that would first need to be reduced to allow a plant’s cellulose to be converted into ethanol. Proponents of the new biofuels counter that the energy crops would reduce both global warming and our dependency on foreign oil. Others worry that the new bioenergy proposals would place a heavy burden on farmers. Rather than rotating corn with other crops, they would be pressed to grow the new ethanol-producing corn year after year. This would strain the soil and allow the buildup of insects and disease, according to The New York Times report.