1 Answers
Red thread disease is a fungal infection found on lawns and other turfed areas. It is caused by the corticioid fungus Laetisaria fuciformis and has two separate stages. The stage that gives the infection its name is characterised by very thin, red, needle-like strands extending from the grass blade. These are stromata, which can remain viable in soil for two years. After germinating, the stromata infect grass leaf blades through their stomata. The other stage is visible as small, pink, cotton wool-like mycelium, found where the blades meet. It is common when both warmth and humidity are high.
Environment
Laetisaria fuciformis, the fungus that causes red thread disease develops more often in cool and wet conditions. These conditions are more present in the spring and fall when rainfall is higher and temperatures are slightly lower. Over 77°F, the growth rate of the fungus decreases significantly, and it ceases at 85°F. Turf grass that is poor in nutrition and are slow growing are areas that are more susceptible to red thread disease. The fungus grows from the thread like red webbing structures called sclerotia. The sclerotia can survive in leaf blades, thatch, and soil for months to years. These areas that have been infected spread the disease by water, wind, and contaminated equipment. Since this fungus can survive for long periods of time it is essential to cure the infected area so further spreading of the disease does not occur.
Management