The pathogen causing dollar spot is currently classified as the fungus Sclerotinia homoeocarpa . Experts on classifying fungi believe it belongs in another genus, but are uncertain which one. Turf text books and research articles still refer to the disease by the scientific name Sclerotinia homoeocarpa. Dollar spot causes disease on all cool season turfgrass species. On golf courses, we are mainly concerned with dollar spot on annual bluegrass and creeping bentgrass.
Dollar spot occurs during the summer and early fall.
As with every turfgrass disease, environmental conditions affect the occurrence and the development of the disease. Dollar spot is more prevalent on turf which has been grown under a low nitrogen fertility regime. After a couple of days these diseased areas take on a bleached appearance, ending with patches that have an average diameter of 3 cm. On longer grass leaf blades, individual lesions can be seen. The symptoms on longer grass appear as irregularly shaped patches with blighted turf in amongst healthy turf.