Curvularia blight of turfgrass can be caused by eight species of fungi. Infected areas of lawn develop yellow or dappled yellow-green patches 2 to 3 inches in diameter. These patches later turn reddish-brown. The patches may expand to form dead areas a foot or more in diameter. The fungi cause root and crown rots, which in turn cause the above-ground symptoms. Leaves of affected grass plants may show yellow dappling from the tip downward and tan, brown, or gray lesions may occur on the leaves. Some grass species may also show a reddish-brown band separating diseased and healthy tissues. The fungi survive on plant debris and diseased tissues at ground level. They are most destructive during warm, wet weather from May to October. The disease is most common on bluegrass and fescue.

Management Options

Non-Chemical Management

Provide proper culture. Adequate, balanced fertilization and deep, infrequent watering will help prevent disease. Water in the morning so grass can dry quickly.
Mow regularly. Do not allow grass to become matted.
Collect clippings to reduce amount of debris on lawn.
Remove thatch and aerify as needed.
For more information on proper care of lawns, including mowing heights and fertilizer recommendations, see EB0482E, Home Lawns.

Select non-chemical management options as your first choice!

Chemical Management

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

Curvularia blight is usually considered a secondary problem resulting from environmental stresses or other disease problems. Use good cultural practices to prevent and correct problems.

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WSU Extension

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