Smut - Ustilago maydis                    Clemson University, USDA Cooperative Extension Slide Series,www.ipmimages.org HOSTS: Corn. (Pasture grasses are susceptible to a similar smut fungus.) DESCRIPTION: Smut is a fungus which causes swelling in aboveground plant tissues (ie. ears of corn). Plant cells become spongy-gray, then black as the spores mature. Galls can be up to 4” in diameter. LIFE CYCLE: Smut fungi overwinter in plant debris. Spore formation begins in the spring and is spread by wind and rain. Infection occurs through wounds, especially under high moisture conditions. CONTROLS: There is no control for this disease after infection. REMOVE AND DESTROY all infected plants. DO NOT compost these plants. Soil applications of raw manure favors infection. Cultural: Grow resistant varieties.
Missoula County Extension Office; Missoula, Montana 59808 - Updated for 2006