This leads to infections that are visible in 10 days or more. Wounds from various injuries provide points for the fungus to enter the plant. The smut fungus is sensitive to temperature and moisture changes. In a warm season, the amount of smut is related closely to the amount of soil moisture, especially during June. When temperatures are lower than normal, there may be little smut even though soil moisture remains high.
Seed treatment is of no value because few spores are on the corn seed.
For the home garden, remove smut galls before they break open and bury or burn them. This must be done on a community basis, however, in order to be effective. Smut gall removal is not practical in commercial production. Mature common smut galls on corn ear. In order to reduce infection points from insect injury, control corn borers as first tassels appear by application of insecticides when insect populations are high.