| Abstrakt: |
Bahiagrass (Paspalum notatumFluegge) is a widely used grass for low maintenance turf areas such as highway rights‐of‐ways in the southeastern USA. Although well adapted to poor soils, low fertility, and low rainfall conditions, bahiagrass requires frequent mowing to maintain turf uniformity because of rapid and prolific seedhead production. This study was conducted in June and August of both 1995 and 1996 to determine the effects of various mowing timings either before or after application of the plant growth regulator AC 263,222 [(AC) (±)‐2‐ [4,5‐dihydro‐4‐methyl‐4‐(1‐methylethyl)‐5‐oxo‐lH‐imidazol‐ 2‐yl]‐5‐methyl‐3‐pyridinecarboxylic acid]. Unimproved bahiagrass turf was clipped to a 7.5‐cm height at times corresponding with the following mowing treatments: mow 3 or 7 d before treatment (DBT) with AC 263,222 (0.07 kg ha−1for all treatments), 1 h before treatment (HBT), 1 after treatment (HAT), 3 or 7 d after treatment (DAT), and control that had been mowed 2 wk earlier. Evaluations of bahiagrass color, seedhead count and height, and vegetative canopy height were made biweekly through 6 wk after AC treatment. Mowing at 3 or 7 DBT with AC resulted in color ratings that were always equal to or above the minimal acceptable rating and also provided at least 90% seedhead suppression through 6 WATin all trials. Mowing bahiagrass at 3 or 7 DAT consistently resulted in color ratings less than the minimal acceptable rating of 5 through 2 WAT, but bahiagrass growth regulation was excellent through 6 WAT in all trials. The mowing treatments of 1 HBT or 1 HAT both resulted in excellent growth regulation characteristics, but color ratings for turf mowed 1 HAT were consistently higher than those for plots mowed 1 HBT. These data indicate acceptable color and plant growth regulation can be obtained by timing mowing events at least 1 h before or after spraying AC 263,222 in low maintenance bahiagrass turf. |
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