Corn: Smut

Biology

Two types of smut occur on corn in the Pacific Northwest. Both are fungal diseases. Common smut may occur on any above-ground portion of the plant, causing gall-like swellings. The galls are initially covered with a greenish to silvery layer of tissue which later dries and breaks open, releasing a mass of olive-green to black spores. Leaf galls typically are hard and do not break open. Common smut is more serious during hot weather. Head smut typically attacks only the tassels and ears. The infected ears and tassels may form leafy structures instead of reproductive parts, or may become masses of spores. The spore masses have thread-like strands of corn vascular tissue in them, which helps distinguish head smut from common smut. Both diseases may be spread by wind-blown spores, and head smut spores may also survive in the soil or on the seed surface.

Management Options

Use Integrated Pest Management (IPM) for successful plant problem management.

Non-chemical Management

Select non-chemical management options as your first choice!

• Plant resistant varieties in areas where smuts are a problem. ‘Blitz’, ‘Commander’, ‘Goldie’, ‘Reliance’, and other varieties are known to be resistant to head smut.
• Rotate crops. Do not plant corn in the same location for at least three years.
• Provide proper culture.
• Remove and destroy any smut galls before they break open and release spores.
• Remove plant debris from the garden. Destroy or discard (do not compost) diseased materials.

Chemical Management

IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.

• None recommended.

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