Quinone outside inhibitor (QoI) fungicides include three fungicide families, the well-known family of strobilurins and two new families, represented by fenamidone and famoxadone. QoI fungicides approved for, or in review for, use on field crops in Iowa include strobilurins azoxystrobin, pyraclostrobin and trifloxystrobin, and famoxadone. These fungicides are used on cereal grains, corn, and soybean as well as many other crops in Iowa, such as fruit trees, small fruit, vegetables, and turf.