Ustilaginoidea virens

False head smut occurs very rarely in hot, dry or humid areas. The fungus commonly infects rice flowers more than maize.

Symptoms differ from those of other smuts of maize. False head smut produces neither tassel malformation nor ear infection, as does true head smut (Sphacelotheca reiliana); only a few isolated male florets in the tassel show dark-green masses of spores (sori). False head smut also differs from common smut (Ustilago maydis) in that no galls are produced.