Influence of Mowing Height and Frequency on Putting Green Speed and Plant Health.

In preparation for golf course tournaments, many turfgrass managers seek increases in the ball roll distances measured on putting greens. The objective of this study was to determine the effect mowing frequency and height on ball roll distance. Two 14-day field studies were conducted in 2015 and 2016 at the Joseph Valentine Turfgrass Research Center located in University Park, PA. Each study was conducted on a ‘A-4’ creeping bentgrass (Agrostis stolonifera L.; CBG) or annual bluegrass (Poa annua L.; ABG) putting green. Plots measured 1.2 x 2.7 m and were arranged in a randomized complete block design with a 3 x 3 factorial treatment structure. For the main effect of height of cut (HOC), mowers were set to a height of 2.1 mm, 2.5 mm, and 2.9 mm. For mowing frequency (FREQ), plots were mowed once, twice, or four times per day. Single cut (SC) and double cut (DC) treatments were performed in the morning whereas double-double cut (DD) treatments consisted of a DC in the morning and again in the afternoon. Ball roll distance (BRD), color and quality were assessed daily. Although a few interactions were present in the ABG study, the main effect of HOC and FREQ were significant on all rating dates. Results showed that plots mowed at 2.1 mm had greater BRD on 100% and 86% of the rating dates when compared to 2.9 mm and 2.5 mm, respectively. For FREQ, DD plots had greater BRD on 93% and 100% of the rating dates when compared to DC and SC, respectively. On CBG, the main effect of HOC and FREQ were shown to be significant on all rating dates. Results showed that plots mowed at 2.1 mm had greater BRD on 100% and 93% of the rating dates when compared to HOC 2.9 mm and 2.5 mm, respectively. Mowing plots 4 times per day (i.e., DD) resulted in greater BRD on 93% and 100% of the rating dates when compared to DC and SC, respectively. For both experiments, color and quality were shown to be reduced during the trial as HOC was reduced and FREQ was increased.