The soybean aphid, Aphis glycines, previously unknown in North America, literally burst on the scene in August 2000, with outbreak populations in soybeans in southern Wisconsin, northern Illinois, southeastern Minnesota, and southwestern Michigan. During the 2001 growing season the aphid outbreak spread to include northeast Iowa, most of eastern Minnesota, all of Wisconsin, eastern Michigan, northern Indiana and Ohio, and southern Ontario, Canada, plus the aphid has now been found to occur in 13 U.S. states ranging from North Dakota to Virginia.