The lengthy legal battle over genetically modified alfalfa will go yet another round, The St. Louis Post-Dispatch reports.

The Center for Food Safety, a group critical of genetically modified crops, has sued federal regulators, alleging the U.S. Department of Agriculture's recent approval of genetically modified alfalfa was illegal. The center alleges the approval is based on faulty information, and that genetically modified alfalfa will damage the organic industry because it could contaminate conventional or organic alfalfa. The alfalfa, developed by Creve Couer,Mo.-based Monsanto, is engineered to withstand applications of the herbicide Roundup, which kills weeds but not the crop.

The newspaper said plaintiffs include dairy farmers who say they could lose the primary forage for their dairy cows if organic alfalfa is contaminated. To maintain organic standards, dairy cows have to eat organically grown hay.

Read more.

And a short history:

• * The USDA initially approved the alfalfa in 2005, but the Center for Food Safety challenged the decision, saying regulators had not performed adequate environmental reviews. A federal judge agreed and banned further planting.
• * Monsanto took the case to the Supreme Court, which lifted the ban last year. The court said that the department would have to complete an environmental impact statement.
• * The statement was finished in December, and last month the USDA said it would "deregulate" modified alfalfa, meaning it can be grown without any government-imposed restrictions.