Dollar spot may persist from early summer until early fall, and its incidence seems to be higher in seasons with low rainfall, presumably from the adverse effect of low soil moisture on host plants. It occurs on bluegrasses, bentgrasses, fescues, and zoysia. The classification of the pathogen that causes dollar spot has undergone numerous changes. With higher cutting heights, the bleached turf spots are irregularly shaped. In the early morning, when dew is still on the grass, a white cobwebby growth of the fungus may be seen over the spot.
Spots coalesce to cover large areas when the disease becomes severe.
On individual grass blades the damaged tissues are first watersoaked and dark colored. The lesions first occur randomly on the leaf blade, and then frequently extend across the entire blade. Older lesions may become quite long and cause blighting of the entire leaf or cut leaf end. The fungus, Sclerotinia homoeocarpa , survives unfavorable periods as dormant mycelium in infected plants, therefore, fungal movement is brought about by equipment, people, animals, wind or water. If night-time conditions become cool and dry soon after infection has occurred, or if control measures are exercised quickly, infection may not progress beyond scattered leaf lesions.