Mowing Operations Influence Creeping Bentgrass Putting Green Ball Roll following Plant Growth Regulator Applications.

Plant growth regulators (PGRs) are commonly used to enhance putting green quality and ball roll distances but their effects with various mowing operations have not been reported. Three experiments were conducted and repeated at Clemson University, Clemson, SC, on an 'L-93' creeping bentgrass putting green to evaluate the effects of mowing operations and PGRs on diurnal ball roll distances. The PGRs tested included ethephon at (a.i.) 3.8 kg⋅ha-1, flurprimidol at (a.i.) 0.28 kg⋅ha-1, paclobutrazol at (a.i.) 0.28 kg⋅ha-1, and trinexapac-ethyl at (a.i.) 0.05 kg⋅ha-1. Mowing operations tested included rolling vs. mowing, morning mowing vs. morning plus afternoon mowing, and single vs. double morning mowing, all with and without PGRs. PGR by mowing operation interactions did not occur in any experiments. Ball roll distances decreased from 12:00 HR to evening observations in all experiments. In Experiment 1, rolling the green without mowing reduced ball roll distance 4% (5 cm) compared to mowing. Turf rolled without mowing in the morning and treated with flurprimidol, paclobutrazol, and trinexapac-ethyl produced similar ball roll at 12:00,15:00, and 18:00 HR to mowed untreated turf. In Experiment 2, all plots were mowed at 08:00 HR and half of each plot was remowed at 12:30 HR. The second mowing at 12:30 HR enhanced ball roll distances 6% (8 cm) over the day. Turf mowed only at 08:00 and treated with paclobutrazol and trinexapac-ethyl had greater or equal ball roll distances at 12:30,15:30, and 18:30 HR to untreated turf that had a second mowing at 12:30 HR. Turf receiving ethephon and 08:00 HR mowing had 4% to 12% (4 to 17 cm) shorter ball roll distances throughout the day compared to untreated turf mowed at 8:00 and 08:00+12:30 HR, respectively. In the third experiment, mowing twice in the morning increased ball roll 3% (4 cm) compared to mowing once. Trinexapac-ethyl and paclobutrazol treated turf mowed... [ABSTRACT FROM AUTHOR]