Typhula Blight Severity as Influenced by the Number of Preventive Fungicide Applications and Snow Compaction

Abstract

Golf course superintendents at high elevations in Colorado have widely adopted a practice of making two or more applications of fungicides for Typhula snow mold control beginning up to a month before permanent snow cover in the belief that this provides better disease suppression than a single application of fungicides just prior to snow cover. Two fall applications of fungicides spaced approximately one month apart were compared to a single application just before snow cover for superiority in controlling Typhula blight. Of the nineteen paired comparisons from two golf courses over a 7-year period, there was only one case in which two applications of fungicides provided better Typhula blight control than a single application. In addition, Typhula blight severity was observed to be reduced in fairway areas where snow had been compacted by placement of Nordic ski tracks, and that this disease reduction in compacted areas was associated with below-freezing temperatures at the turfgrass surface that are inhibitory to Typhula growth. Accepted for publication 5 June 2013. Published 21 August 2013.