Smuts

General Overview

Smuts are a fungal disease that gets their name from the sooty black spore masses they produce. However, they can be a serious disease of corn, grains, and onions grown from seed. Some also affect anemones, gaillardia, ribbongrass, calendula, gladiolus, and dahlia. Few are a problem for the home gardener unless you grow sweet corn. Smuts may also occasionally be encountered as a fungal disease in lawns.

Common Corn Smut

Common smut (Ustilago maydis) often affects field, popping, and sweet corn, and involves a gall(s) to form on the corn ears and other parts. These galls are dramatic in appearance often white to gray-silver. It rarely affects crop yield but can diminish quality. These galls, when fried, have been a delicacy in Mexican cuisine since the Aztecs.

Integrated Pest Management Strategies

1. Rotate crops. Rotating affected corn (sweet, popping, and field) every few years will help keep the infection rate lower. Spores can survive in soil for several years. 

2. Cultivars. Choose less susceptible cultivars such as 'Ambrosia', 'Apache Gold', 'Aztec', 'Bellringer', 'Calumet', 'Capitan', 'Cherokee', 'Comanche Hybrid', 'Comet', 'Cup', 'Golden Gleam', 'Golden Security', 'Merit', 'Serendipity', 'Stylepak Hybrid', 'Sweet Sue', 'Tendersweet', and 'Wintergreen'.

3. Cultivation. Keep plants stress-free, reduce splashing water, and avoid excess nitrogen. 

4. Avoid injury. Injuries allow points of entry for the fungus to infect the plant.