Envu Solutions – Snow Mould
Pink and grey snow mould are destructive turf diseases that can devastate putting greens, tees, fairways, and roughs under prolonged snow cover. Beyond being unsightly in spring, they weaken turf health and can make surfaces unplayable. These diseases affect all cool-season turfgrasses but are especially severe on annual bluegrass and bentgrass.
Cultural practices such as avoiding late-fall fertilization that promotes lush growth, reducing thatch, removing tree leaves, managing drifting snow, and improving drainage can help reduce disease severity.
Infection timing: While symptoms appear under snow, infection for both pink and grey snow mould begins in the fall. As temperatures fall below 10 °C, risk accumulates in what are known as Heating Degree Days (HDDs), a tracking system similar to Growing Degree Days used for plant growth.
Application strategy:
- At 25–50 HDDs (typically 3–4 weeks before winter’s final application), a “go-in clean” spray—such as Fame® SC or Signature™ XTRA Stressgard® — reduces inoculum and strengthens disease protection. For more information on the go-in clean strategy see “Using the Go-in clean strategy for early inoculum knock-down”.
- A final fungicide application should be made after the last mowing of the season, around 100 HDDs, just before snow cover. Programs including two or three active ingredients—such as Dedicate® Stressgard®, or tank mixes with Fame SC and Mirage® Stressgard®, or Signature XTRA Stressgard—delivers excellent and long-lasting snow mould control.
New for 2025: Signature™ XTRA Stressgard® now labelled for Microdochium patch control60g 7-day, 120-180g 14-21 day, and 200g 21-day rates. The only phosphonate in Canada labelled for CONTROL of Microdochium patch, Pythium Root Rot and Blight, and Anthracnose foliar and basal rot. |
Additional benefits: Multiple years of research have demonstrated that Stressgard formulations not only provide excellent snow mould control but also improve turf quality and vigor following snow melt. However, if treated areas experience abnormal weather, heavy rainfall, or snowfall that melts before permanent cover, a repeat application may be necessary to maintain effective protection.
To view trial results, HDD-based application timing charts, and more detailed product recommendations, be sure to download the solution sheet