Ear rots and storage molds occur every year on corn throughout the Midwest. These diseases are serious concerns in corn production because they cause losses in grain yield and quality, and pose potential animal health risks from feeding moldy grain, due to the presence of toxic chemicals (my co toxins). Fungi can produce many chemical products, some of which are medically useful, while others (mycotoxins) are toxic to animals and/or people. There are many fungi that can be present on corn, and several of the common species are toxigenic. Because of losses in yield and quality and the possibility of mycotoxin production, it is important to recognize ear rots and storage molds and be aware of their toxigenic properties.