An anonymous reader writes "NPR reports that an Oregon wheat farmer found a patch of wheat growing where he did not plant. After RoundUp failed to kill the plants, he sent them to a lab for testing. Turns out the wheat in question is a GMO strain created by Monsanto but never sent to market. Oregon field trials for the wheat ended in 2001. 'Nobody knows how this wheat got to this farm. ... After all such trials, the genetically engineered crops are supposed to be completely removed. Also, nobody knows how widely this genetically engineered wheat has spread, and whether it's been in fields of wheat that were harvested for food.' The USDA is currently investigating and says there is no health-risk. Meanwhile, Monsanto has released a statement and Japan has suspended some wheat imports from the U.S. 'The mystery could have implications on wheat trade. Many countries around the world will not accept imports of genetically modified foods, and the United States exports about half of its wheat crop.'"