When the fresh wheat samples arrived at her lab this spring, Carol Mallory-Smith, a weed scientist, didn’t know what to expect. The concerned farmer who sent them had contacted her because a patch of wheat had refused to die after being treated with a powerful herbicide called Roundup. “The farmer asked me if the wheat could have evolved a natural resistance to the herbicide,” says Mallory-Smith, “but I said that that wasn’t possible because of the way wheat is exposed to Roundup.” Then the grower mentioned the possibility that Monsanto’s genetically modified wheat seeds might have made their way into the field somehow. “I thought that was extremely unlikely,” she adds. “Obviously, I was wrong.”

On May 1, with GMO-positive test results in hand, Mallory-Smith contacted the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service to tell them that unapproved seeds which had been engineered 14 years beforehand by one of the biggest agricultural companies in the world, Monsanto, had somehow found their way into a wheat field in Oregon. And on May 29, the USDA alerted the public about the genetically modified wheat's presence in Oregon. Now, more than two months after its discovery, the USDA still hasn’t released any information on the wheat’s origins. And although we may never find out how those seeds made it to that particular field, we can at least explain what makes these seeds so special in the first place.

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Roundup Ready soybeans were the first Roundup Ready crop to gain USDA approval, in 1994. Four years later, Monsanto started testing its Roundup Ready wheat in the U.S. The testing took place in 16 states for a period of seven years. With what appears to have been successful test results in hand, Monsanto consulted in 2005 with the National Association of Wheat Growers to assess the genetically modified wheat’s market viability. Unfortunately for Monsanto, the farmers’ reactions were underwhelming.

“Wheat growers weren’t interested because their customers weren’t interested,” says Blake Rowe, CEO of the Oregon Wheat Commission. Monsanto decided not to seek USDA approval for the wheat because the market wasn’t ready for it. The company discontinued the U.S. wheat tests instead and burned most of the seeds—43 seed containers were kept in a Colorado storage facility until their incineration in 2011. But burning the entirety of the Monsanto's seed stock apparently didn’t stop the GM wheat from popping up in Oregon earlier this year.

“It would be nice to know how the wheat got there,” Rowe says. “We don’t want to solve the wrong problem and waste a bunch of effort because of speculation.” No matter where the seeds came from, “this is not an event that farmers welcome in any way, shape or form,” he adds. For Oregon farmers, public opinion matters, and the media coverage surrounding U.S. wheat is worrisome. “We’re definitely ready,” he says, “for things to go back to normal."