By Payton Perkinson and Kevin W. Frank, Michigan State University
With the recent cooler temperatures, it is starting to feel like fall. However, fall in Michigan can be short lived, and winter is just around the corner. Winter is a stressful time for golf course superintendents because of the possibility of winterkill. Reestablishing turfgrass in the spring is challenging due to the cold conditions that are unfavorable for seed germination.
This spring we, along with researchers at Iowa State University, University of Wisconsin, and University of Minnesota, investigated how well creeping bentgrass and annual bluegrass can establish during early spring when soil temperatures are not optimal for germination. At two of the sites, we seeded into putting green root zones, at another into a bare soil green that had the preexisting sod removed with a sod cutter, and at the fourth site a native soil green that was killed using nonselective herbicide (Figure 1). Once soil temperatures were warm enough, we seeded five creeping bentgrass cultivars, an annual bluegrass seed (Figure 2), and a 50:50 by weight mixture of creeping bentgrass and annual bluegrass seed (this was done to simulate how a Poa annua in the seedbank would affect establishment of the creeping bentgrass); seeding occurred three consecutive weeks. Throughout the study we took percent coverage data and once plots reached 100% established, we applied fluazifop-P-butyl to each plot, which killed all the creeping bentgrass and left only Poa annua, allowing us to quantify how much annual bluegrass contamination was in each plot.
We are also part of other WinterTurf field experiments relating to snow mold. This fall we will be completing the second year of research on the effects of fertility timing and rate on snow mold incidence on a creeping bentgrass fairway and leaf mulching in home lawns on snow mold development.