Snow Mold Surprise February 27, 2015

Snow Mold Surprise

By Bob Vavrek, Senior Agronomist
March 18, 2008

Several courses across the Region have already reported unusually heavy gray snow mold injury now that the heavy, persistent snow cover has finally begun to melt. A fair amount of winter disease should come as no surprise considering the frequent, heavy snowfall this season.

Another, sometimes overlooked, factor that contributes to the potential for damage on fairways and tees is the budget crunch that many courses have faced during the past several seasons. Private and public courses throughout the north central tier of states have been feeling the economic pinch of increasing costs for labor/materials and decreasing dues/green fees. Consequently, many turf managers have significantly reduced the rates of fungicides applied to non-putting green areas of the course. The end result can be snow mold breakthrough during an unusually harsh winter.

Fortunately, gray snow mold usually causes little more than superficial injury to the turf foliage, in contrast to a severe outbreak of pink snow mold, which can damage roots and crowns. Color of the mycelium can often be used to differentiate pink from gray snow mold. However, once the lesions dry out a bit, the different colors can fade. Look closely for the characteristic tiny orange/brown/black masses of mycelia (sclerotia) on the leaves and sheaths of plants infected by gray snow mold. Pink snow mold does not produce these structures.

An effective, inexpensive way to accelerate the rate of recovery from superficial snow mold damage is to fluff up the matted diseased turf with leaf rakes or a very light vertical mowing operation. This will help dry out the affected sites and stimulate new turf growth without the need for a costly early season fertilizer applications that may have the undesirable effect of forcing topgrowth at the cost of limiting root growth. With one strike against the turf during early spring, there is no reason to risk a second strike before the heat of summer and heavy play arrives by management that could result in weak, shallow rooted playing surfaces.

Source: Bob Vavrek, or 262-797-8743