Red Thread

Symptoms: Lawns infected by red thread may have a pink-to-reddish cast when viewed from a distance. If moist grass is viewed more closely, pinkish growth and tiny cotton candy tufts of spores may be seen. In drier conditions, tiny red threads of the red thread fungus may be seen extending from the leaf tips. The grass itself may show irregular patches of dead and dying leaves, giving the lawn a ragged appearance. These diseases can be found on many turf grass species but are seen most often on perennial ryegrasses and fine fescue. The diseases are restricted to the leaves and are not usually very destructive. Both fungi occur mostly in the spring and fall in cool 65-70 degree, moist weather. Disease Cycle: The fungus survives in the thatch when dry. Some spores or pieces of fungus may be airborne, but the fungi are commonly spread by water, feet and mowing. Infections are most common on slow-growing grass stressed by compaction, drought, low temperatures or inadequate fertility. Cultural Management: Although we have no control over periods of prolonged cool, moist weather, it is possible to prevent or reduce red thread through good lawn care practices. Watering should be infrequent and deep. Avoid frequent sprinklings late in the day that extend the time that the grass blades stay wet. Soil fertility must be balanced. These diseases are most common in nitrogen-deficient turf. If red thread is found in slow growing grass, it may be helpful to temporarily collect clippings during mowing to reduce the amount of fungus returned to the lawn. Aeration of compacted soil will improve turf growth and reduce these diseases. Chemical Management: Fungicides are not necessary for red thread. Typically a light dose of fertilizer will help the disease grow out and run its course; however, a fungicide application will help aid in a quicker recovery.

Notice the “thread like” strands developing of the grass blade