Goss’s wilt and leaf blight is caused by the bacterium Clavibacter michiganensis subsp. nebraskensis (Cmn). The disease was first reported in Nebraska in 1969 and soon after in the surrounding states including Iowa. Corn breeders identified resistance to the bacterium and by the 1980s the disease was no longer a threat to corn production except in eastern Nebraska. In 2008, Goss’s leaf blight was reported in eight counties in Iowa. In 2011, the disease was widespread throughout the state and up to 50 percent yield losses occurred in some fields.