The USDA has found unregulated genetically engineered wheat in Montana. This is the second incident that USDA has encountered, the first being in Oregon last year. The Montana incident is "on a smaller scale" than the Oregon incident, the USDA says.

So far, no genetically engineered wheat has been approved in the U.S. The unapproved wheat can also cause issues with trade. The Oregon incident spurred several Asian countries to place a temporary ban on U.S. wheat imports, Mary Clare Jalonick reported for the Associated Press.

The wheat found in Montana was found on one to three acres. It is a different variety than what was previously found on more than 100 acres in Oregon. The plants were found at a university research site in Huntley, Montana. The site was previously used by Monsanto, a seed company, 11 years ago to test genetically modified wheat. The USDA is investigating the wheat discovery.