Common Smut

Common smut is easily recognized by the tumorlike galls that form on any aboveground plant part. The conspicuous galls that replace kernels are covered with a greenish-white papery tissue. As the galls mature, the interior darkens and turns into masses of powdery, dark olive-brown to black spores. Ear galls may reach several inches in diameter. Galls that form on other plant parts, including the tassels and leaves, are much smaller.