Affected plants often appear water soaked and slimy. Sometimes mycelium can be seen on dew-covered grass in early morning. The dead tissue may mat together somewhat like paper-mache and form a crust over the soil surface. Mycelium of Rhizoctonia solani on perennial ryegrass. Dense, white mycelium of damping-off fungus on seedling turf.
Most soils contain fungi that can attack seeds and seedlings.
When conditions are favorable for grass seed germination and growth, as in the early fall and spring, these organisms usually are of little significance. Warm, wet weather, however, is more favorable for damping-off fungi and less favorable for seedlings. Under these conditions, fungi can severely damage seed and seedlings. Such wet conditions over long periods of time are ideal for invasion by damping-off fungi. High rates of fertilizer can produce a succulent turf that is more susceptible to attack by damping-off fungi.