WASHINGTON/PRNewswire/ -- In releasing the results of their third annual survey of U.S. grain elevators, the American Corn Growers Association (ACGA) reports that over half of the elevators surveyed are requiring segregation of GMOs from non-GMO varieties either upon arrival at the elevator or on the farm. Almost 20 percent reported offering premiums for non-GMO corn or non-GMO soybeans. The survey included 1,149 grain elevators in 11 mid-western states.