‘Tifway’ Bermudagrass (Cynodon dactylon x transvaalensis ‘Tifway’) is a popular turfgrass utilized on golf course fairways and athletic fields. Aggressive summer growth habit, fine leaf texture, and dark green color attribute to the popularity of ‘Tifway’. In order to reduce mowing requirements, suppress seedheads, enhance color, and to sustain a uniform playing surface, plant growth regulators (PGRs) have been widely used on ‘Tifway’ bermudagrass.
The study was performed for 12 weeks from 15 June to 7 September, 2005 and 24 June to 16 September 2006 on Clemson University’s registered Tifway bermudagrass [Cynodon dactylon (L.) x C. transvaalensis Burtt-Davy] research plot. The study evaluated trinexapac-ethyl, flurprimidol and paclobutrazol applied exclusively and as tank mixes. The rate for trinexapac-ethyl and flurprimidol was 12 oz A-1 (0.88 L ha-1) and 8 oz A-1 (92 g ha-1), respectively. Two rates of paclobutrazol were evaluated, 16 and 32 oz A-1 (1.2 L ha-1 and 2.3 L ha-1). Exclusive applications and tank mixes of trinexapac-ethyl, flurprimidol and paclobutrazol resulted in eight treatments total. Applications were made every 21d for the duration of the study.
Clippings were harvested at 4, 8, and 12 weeks after initial treatment (WAIT) using a walk mower set to a 16mm height. Clipping weights for all Primo and Cutless treatments were compared to untreated plots to calculate percent clipping reductions. Percent horizontal regrowth was measured every 14d. Tifway bermudagrass injury was evaluated weekly. Injury was rated visually on a scale from 0-100% with 30=maximum level of acceptable injury.
