This spring, superintendents may observe higher levels of Microdochium patch (Microdochium nivale), formerly called pink snow mold, or gray snow mold (Typhula species). Pink snow mold was renamed Microdochium patch by the American Phytopathological Society because the disease appears pink only under certain conditions and snow cover is not a requirement for disease development. The temperate early winter weather that was great for some extra rounds of golf likely led to more rapid breakdown of preventative snow mold controls. Research from the University of Wisconsin indicates that mild temperatures in conjunction with rain or snowmelt are the leading causes of the premature break down of preventative snow mold controls. Products applied during the “traditional” application window in the Northeast, and not followed by a subsequent application, may have worn off because they were subjected to mild temperatures and rain or snowmelt events.
What should be done if disease develops at your course? In the case of Microdochium patch, monitor the outbreak for additional disease development. If only a few patches are noted, the best solution may be to do nothing. If the patches progress and the outbreak is worse than acceptable levels or on a high-profile surface – e.g., putting greens, clubhouse lawns or highly visible locations – spot treatments may be necessary. Also, consider the weather; a prolonged period of cool, moist weather can stimulate disease development. If the weather does not cooperate, additional control measures likely will be necessary. Moreover, equipment, golfers and carts can spread Microdochium patch.
Conversely, no additional chemical control is necessary if gray snow mold is persistent during early spring. Recovery can be accelerated with physical disturbance of the affected areas to remove matted leaf tissue in conjunction with light fertilizer applications to stimulate growth.
Many superintendents in the southern tier of the Northeast Region are experiencing a different source of frustration: poor Poa annua control. For those with warm-season turfgrass, Poa annua control is frequently accomplished with nonselective herbicides when the desirable warm-season grass is dormant. However, warm temperatures in December and early January caused bermudagrass to break dormancy, delaying nonselective herbicide applications. Now, bermudagrass finally is dormant, but frozen or extremely wet conditions have prevented herbicide applications. Warm fall conditions may have reduced the residual of preemergence herbicides applied to control Poa annua. Fear not, there still is time to apply weed-control products if the weather cooperates just a little and soils dry.
Northeast Region agronomists are already scheduling Course Consulting Service visits, so be sure to contact us if you have a specific date in mind for a visit.
Northeast Region Agronomists:
David A. Oatis, regional director – firstname.lastname@example.org
James E. Skorulski, agronomist – email@example.com
Adam Moeller, agronomist – firstname.lastname@example.org
Elliott Dowling, agronomist – email@example.com
Addison Barden, agronomist – firstname.lastname@example.org