Cultural, Organic, and Biological Methods for Snow Mold Control on Putting Greens in the Intermountain West

Abstract

Core Ideas Topdressing every 2 wk reduced snow mold severity by 11% compared with every 4 wk in 1 of 2 yr. This cultural practice should be evaluated further for managing winter diseases. Compacting snow with snowshoes reduced snow mold severity 3% the first year but had no effect the second year when damage occurred before snow could be compacted. Organic fertilizers, biological materials, and the compost did not provide adequate control of snow molds. A mineral oil was the only nonfungicidal commercial product to have efficacy on snow molds. Turf treated with traditional fungicides PCNB and propiconazole prior to snow cover had the best control of snow molds. Snow mold pathogens can damage golf course turf in winter, and few alternatives to fungicides currently exist for effective control. Cultural strategies including sand topdressing frequency and snow compaction using snowshoes, in combination with organic and biological commercially available products, were evaluated for snow mold control on a putting green for two seasons. Sand topdressing every 2 wk during the growing season reduced snow mold severity 11% in 2010, and compacting snow in winter reduced severity by 3%. Neither cultural practice reduced damage in 2011, when pressure from snow molds was higher. Most organic and biological materials did not suppress snow molds in either year relative to the fertilizer control, whereas turf treated with traditional fungicides provided the best control. A mineral oil was the only alternative material to have efficacy on snow molds, providing 54% control in 2010 and 34% control in 2011.

Controlling Snow Molds with CIVITAS TURF DEFENSE in Utah

“…Civitas has not fared well in Wisconsin on Typhula snow molds (Koch, 2016a) or Microdochium patch/pink snow mold (Koch, 2016b) under lengthy snow cover, but has provided good suppression of pink snow mold where snow persists on Nordic golf courses (Aamlid et al, 2018). Earlier work from Utah showed Civitas has activity on snow molds (Van Dyke and Johnson, 2017) but applications were made all season, and efficacy was still influenced by disease severity as it related to snow cover between years. The length of snow cover is impossible to predict each year, so using traditional fungicides is fundamental to a snow mold program in northern climates.…”

“…The length of snow cover is impossible to predict each year, so using traditional fungicides is fundamental to a snow mold program in northern climates. However, including Civitas with other fungicides has had positive effects on spring quality when snow melts (Aamlid et al, 2018; Van Dyke and Johnson, 2017).…”

“…Koch and Hockemeyer (2019) report many effective fungicides for managing snow molds. CIVITAS TURF DEFENSE (Intelligro/Petro‐Canada Lubricants, Mississauga, ON) is a novel fungicide with efficacy on snow molds (Van Dyke and Johnson, 2017). The FRAC code is “not classified” (Vincelli et al, 2017) and the mode of action is different from traditional fungicides.…”

Volatilization or Recovery of Fairway Foliar Nitrogen Fertilizer via Time and Spray Oil Inclusion

“…The impetus for the latter includes reports of reduced pesticide requirements when using Civitas in a disease management program [3][4][5][6][7][8][9]. Having a unique mode of action relative to traditional fungicides, Civitas features a fungicide resistance action committee (FRAC) classification of "not" [10], is OMRI listed (Organic Materials Review Institute, Eugene, OR), and proves useful in organic management programs or where cosmetic pesticide use is prohibited.…”