Water management on golf course turf

Effective irrigation management is important to the successful operation of any golf course. Studies were done in 1995 and 1996 in a golf to: (1) measure variability in evaporation across a golf course and the accuracy of weather station-estimated evapotranspiration (ET) estimates; (2) evaluate effects of four plant growth regulators on drought response of perennial ryegrass (Lolium perenne L.); and (3) evaluate the effects of the irrigation management on pest incidence on a perennial ryegrass golf course fairway.; Evaporation was measured using black Bellani plate atmometers placed on four golf tees and near the weather station at the Manhattan Country Club, Manhattan, KS. Evaporation at the weather station was up to 22% higher than that at locations on tees, and varied by over 20% among tees. Evaporation on a north-facing slope was 8% lower than that on a level surface or south-facing slope. Weather station-estimated empirical ET was consistently higher than ET estimated from atmometer evaporation.; Trinexapac-ethyl (4-(cycloproply-{dollar}alpha{dollar}-hydroxy-methylene)-3,5-dioxo-cyclohexanecarboxylic acid ethyl ester) enhanced turfgrass quality during drought in the greenhouse; had no deleterious effects on rooting; and suppressed canopy height for up to two weeks in the field. Ethephon ((2-chloreoethyl) phosphonic acid) enhanced quality during drought in the greenhouse; reduced root length density (RLD) in the field at 0 to 20 cm; and had no effect on canopy height. Mefluidide (N-(2,4-dimethyl-5-(((trifluoromethyl)-sulfonyl) amino) phenyl) acetamide) caused unacceptable quality; reduced rooting at 0 to 40 cm; and suppressed canopy height. Pcaclobutrazol ((2RS,3RS)-1-(4-chlorophenyl)-4.4-dimethyl-2-1,2,4,-triazol-1-yl) penta-n-3-ol) had negligible effects on ryegrass quality, rooting, and canopy height.; About 200% more water was applied to perennial ryegrass turf irrigated daily with 7.6-mm water regardless of prevailing weather conditions, than to the turf irrigated to replace approximately 80% of atmometer-estimated ET three days weekly. In general, a preventive fungicide application regime resulted in more active ingredient application than a curative schedule. Daily irrigation suppressed brown patch (Rhizoctonia solani Kuhn) injury by 44% in 1995 and 20% in 1996, but increased dollar spot numbers in 1996.