Alternatives to conventional fungicides provide limited suppression of snow mold diseases on amenity turfgrass

Turfgrass managers rely on fungicides to suppress snow mold diseases in areas with persistent snow cover, which are most commonly applied once or twice in late fall prior to snow onset. Increasing governmental regulations limiting fungicide usage in many parts of the world have heightened the need for alternative means of snow mold control. A two year study was conducted at three sites (Wausau, WI; Marquette, MI; Gaylord, MI) to assess the effectiveness of non-traditional fungicides in controlling snow mold diseases of golf course turfgrass. Most products tested were ineffective in controlling snow mold diseases under high pressure conditions. The mineral oil-based product Civitas® performed moderately well and in one instance performed just as well as the positive fungicide control. Adding the commercial adjuvant Activo® to a reduced rate of fungicide did improve snow mold control, but not always to the same level as the higher rate of fungicide. These results indicate that current commercially available options for non-traditional snow mold control are largely ineffective and that additional research is needed to identify strategies and products that suppress snow mold without reliance on traditional fungicides.