RESEARCH NEWS PROJECT NAME:
Winterkill and Nutrient Management Research Update Dr. Kevin W. Frank and Eric Galbraith Michigan State University I. Winterkill Research Projects 1. MTF funding is used to complement project costs that are not supported by the WinterTurf grant, including supporting Eric Galbraith, research technician. 2. Grad students involved: Payton Perkinson – winterkill reestablishment research projects were the focus of Payton’s Masters thesis research which was completed in 2024. 3. Research benefits turf managers in identifying best practices for reestablishment following winterkill, potential effects of fertilizer rate and timing on snow mold incidence, leaf mulch effects on snow mold and turfgrass health, and the effect of late fall topdressing on turfgrass health.
and an unseeded control. To simulate winterkill, nonselective herbicide was applied twice prior to seeding and plots were vertically mowed in two directions. Seed was applied at 2 lbs 1,000 ft-2 three consecutive weeks once soil temperatures reached a daily average of 45°F at a 2-inch depth. Digital image analysis was collected for five weeks during the establishment period to assess turfgrass cover. Seeding date 1 had the highest turfgrass cover in both years at the beginning of data collection, but by the end of the study, seeding date was not significant. In 2023, Penn A-4 and Penncross had the highest turfgrass cover but differences were small and biologically insignificant. In 2024, there were no differences among creeping bentgrass cultivars and in both years Two-Putt was one of the worst performing entries. Although seeding early before soil temperatures are optimum results in higher turfgrass cover, the benefit is short-lived for only a couple weeks.
4. Reestablishment projects were completed in 2024. The fertility and snow mold, leaf mulch and snow mold, photoinhibition, and topdressing study will be completed in 2025.
Reestablishment on an annual bluegrass putting green At MSU we conducted a reestablishment trial on a native soil annual bluegrass green. The objective of this study was to evaluate spring establishment rate of creeping bentgrass (Agrostis stolonifera L.) and annual bluegrass (Poa annua var. reptans (Hauskn.)) seeded three consecutive weeks in the spring of 2023 and 2024. Seed entries included creeping bentgrass cultivars, ‘Penncross’, ‘Pure Distinction’, ‘Declaration’, ‘Penn A-4’, one annual bluegrass seed, ‘Two-Putt’, a 50/50 by weight Pure Distinction and Two-Putt mix,
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Photo of the research area on May 8, 2025, one month after the first seeding date.
Fertilizer rate, timing, and leaf mulch effects on snow mold There are three different research trials related to snow mold that we have conducted in cooperation with Dr. Koch at the University of Wisconsin. All these trials are completing their 3rd and final year of research in 2025. There are two trials studying the effect of nitrogen and potassium applications on snow mold incidence on a creeping bentgrass fairway. Trial 1 is analyzing the effect of annual rate of nitrogen and potassium on snow mold incidence.
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