From the L.A. Times:
Contamination of organic and traditional crops by recently deregulated, genetically modified alfalfa is inevitable, agriculture experts said, despite Agriculture Secretary Tom Vilsack's recent assurances the federal government would take steps to prevent such a problem.
Many farmers had been pushing the U.S. Department of Agriculture to approve the use of genetically modified alfalfa. Monsanto developed the seed to resist the weedkiller Roundup, allowing farmers to use the two together to save time and labor on weeding. Supporters also say the use of the genetically modified seeds lets farmers grow more alfalfa on each acre and helps keep food prices low.