Genetically modified wheat not approved for sale or commercial production in the United States has been found growing in a field in Washington state, according to the Associated Press. The spread of the GMO wheat poses a risk to trade with countries concerned about engineered food.

The Christian Science Monitor also reported on the story. Here is an excerpt from their report:

A farmer discovered 22 plants in an unplanted field, and the wheat was developed to be resistant to the herbicide known as Roundup, created by seed giant Monsanto, the USDA said. An agency spokeswoman did not know where in the state it was found.

Federal officials said they were working with the farmer to ensure that none of the modified wheat is sold. Out of caution, the agency said it is holding and testing the farmer’s full wheat harvest, but so far it has not found GMOs.

This isn’t the first time GMO wheat has been discovered where it doesn’t belong in the Pacific Northwest. In 2013, GMO wheat was discovered in Oregon, according to The Oregonian:

Stunned researchers at Oregon State University couldn’t help but question themselves. Once, twice, three times in early May — in two different labs — they analyzed DNA extracted from wheat plants grown on an eastern Oregon farm.

A farmer’s attempt to kill the plants with weedkiller had failed, and a growing cadre of university and state agriculture officials wanted to know why. With each test, the result was the same: The wheat had been genetically modified to resist glyphosate, the key ingredient in the herbicide Roundup.

But that didn’t make sense. The last Oregon test plantings of a “Roundup Ready” variety of wheat developed by Monsanto, which makes the herbicide, had ended 12 years before.