Evaluation of Fungicides for Managing Dollar Spot Disease with Multi-Class Resistance in a Mixed Fairway Stand of Creeping Bentgrass and Annual Bluegrass on a Golf Course in Barnstaple, MA, 2025

Dollar spot caused by the fungus Clarireedia jacksonii is a destructive disease of turf grass that thrives in cool wet conditions. It appears as round sunken patches of blighted turf that mature to the size of a silver dollar. This report evaluates the efficacy of commercial fungicides to control dollar spot that has shown multi-class fungicide resistance in a mixed fairway stand in Barnstaple, MA. A field trial was conducted at the Wianno Golf Club during the summer of 2025. Results showed fungicides Densicor, Ascernity, and Posterity provided near-total control of dollar spot under wet coastal conditions. The results offer guidance for turf managers seeking treatment options in the coastal New England region.