Lawn Diseases

Snow Molds

Fusarium Patch

Snow Molds
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Snow molds show up in at least two forms; both prosper in wet, cold weather, especially if grass remains soaked for long periods. Gray snow mold causes irregular dead, bleached patches up to 2 feet across; gray mold is visible on the grass. Pink snow mold produces circular, light brown patches, sometimes blotched with pink fungus.
Affected grass pulls up easily. To correct the problem, aerate the lawn, improve drainage, avoid high-nitrogen fertilizer late in fall, and reduce snow pileup.