Agriculture Secretary Tom Vilsack announced on Thursday that he would authorize the unrestricted commercial cultivation of genetically modified alfalfa.
Mr. Vilsack overlooked a proposal to restrict the growing of genetically engineered alfalfa to protect organic farmers from contamination.
The crop, developed by Monsanto and Forage Genetics, an alfalfa breeder, contains a gene that makes the plant resistant to the herbicide Roundup, allowing farmers to spray the chemical to kill weeds without hurting the crop.
Alfalfa is grown mostly to make hay that is fed to dairy cows and horses. More than 20 million acres are grown in the United States, making it the nation’s fourth-largest crop by acreage behind corn, soybeans and wheat.
In deciding whether to approve the genetically engineered alfalfa, the Agriculture Department was considering restricting areas where the crop could be planted. That, Mr. Vilsack argued, would help prevent litigation, like the lawsuits that have already delayed the approval of genetically altered alfalfa and sugar beets.
This decision has potentially serious implications for organic farmers. Organic farmers can lose sales if genetic engineering is detected in their crops, which occurs either through cross-pollination from a nearby field or from intermingling of seeds. And exports of non-organic but non-engineered crops to certain countries can be jeopardized if genetically engineered material is detected in significant amounts.