Michigan Turfgrass Foundation Funded Research.
Thomas A Nikolai PhD, The Doctor of Green Speed and King of Customer Satisfaction & Eric Galbraith Research Technician Extraordinaire
On February 12, 2024, Research Technician Eric Galbraith initiated a daily double rolling putting green study at the Hancock Turfgrass Research Center. My request was simple, “Every day when there is no snow on the site, please double roll them and periodically take green speed measurements”.
IMAGE 1. Eric Galbraith collecting green speed measurements on the daily double roll putting green plots March 12, 2024. At this point it is easy to distinguish the daily double rolled plots from the non-rolled plots.
Early in the experiment it appeared we might have been putting too much stress on by double rolling too early in the year, however as time passed our fears were proven misguided (see image 2 below) as the double rolled plots began to appear healthier compared to non-rolled plots.
IMAGE 2. Double rolled plots have number 1 below them while non-rolled plots have the number 2 beneath them. As the plots came out of dormancy the double rolled plots quickly displayed a darker rich color.
During the summer and fall of 2024 data indicated the double rolled plots had less disease, held more water as measured with a TDR, had lower surface temperatures and maintained a green speed average in the vicinity of 2 feet longer compared to the non-rolled plots.
On November 22, 2024, Eric inoculated a 1 square foot area on each plot with snow mold (see image 3).
IMAGE 3 Plots were inoculated with snow mold on November 22, 2024. After plots were inoculated the double rolled plots were NOT rolled for 14 days to allow the inoculum to settle below the turfgrass canopy.
By December 27, 2024, there were visual differences in the snow mold inoculum. What does this mean? Well let’s say we are not certain as of yet (see image 4) but the visuals are interesting.
IMAGE 4 The snow mold inoculum on double rolled vs non-rolled plots certainly appear different. What does that mean in terms of disease impact, time will tell
On March 14, 2025, Mike Rabe took the first green speed measurement of this year. His measurement resulted in a green speed increase of 4 feet 4-inches on the double rolled plots vs the non-rolled plots. We call that “customer satisfaction in the shoulder seasons”. All done, so far, with nothing but positives in the regular season as well, but wait, there is more. On March 19, 2025, we mowed the research site plot for the first time this year. After mowing the double rolled plots averaged 3 feet-3 inches longer ball roll compared to the non-rolled mowed plots. Additionally, the double rolled plots held more water as measured with a TDR yet they were significantly firmer than the non-rolled plots measured with the USGA Tru Firm. Roll-on.