Traffic and cultural practice influences on a fairway creeping bentgrass turf

Research was initiated to determine the interactive effects of irrigation frequency, clipping return or removal, and nitrogen rate on turfgrass quality, fairway playing conditions, and annual bluegrass competition under simulated fairway conditions. A \u27Penncross\u27 creeping bentgrass (Agrostis palustris Huds.) turf was established in 1988 on a Sharpsburg silty-clay loam (Typic Argiudoll). Experiments were conducted from 1989 to 1991 under both traffic and nontraffic conditions. A split-split-plot experimental design was used. Daily or biweekly irrigation, clipping return or removal, and 5, 15, or 25 g N m$\sp{-2}$ yr$\sp{-1}$ were the main-, sub-, and sub-sub-plot treatments, respectively. Treatments were replicated 3 times in a randomized complete block design. The turf was mowed 4 times weekly at a 13 mm. Core cultivation was practiced twice each year and topdressing was applied immediately after cultivation. Soil contaminated with annual bluegrass annual-biotype was used for topdressing. Annual bluegrass perennial-biotype vegetative plugs were transplanted. Traffic simulation was applied as 5 passes of a specially-designed traffic simulator, twice weekly during the growing season. Turfgrass color and quality improved with irrigation frequency, nitrogen rate, and no traffic. Thatch accumulation increased with daily irrigation, clipping return, nitrogen rate, and lack of traffic. Golf ball roll improved with clipping removal, low nitrogen rate, and trafficking. Divot injury was positively correlated (r = 0.42 to 0.76) with soil moisture level. Injury increased with daily irrigation, nitrogen rate, and no traffic. However, divot recovery increased with daily irrigation, clipping return, nitrogen rate, and lack of traffic. Annual bluegrass annual-biotype density increased with biweekly irrigation, clipping return, nitrogen rate, and trafficking. Perennial-biotype encroachment increased with nitrogen rate and trafficking. These various interactions support the need for a combination of management practices to maintain quality fairway and reduce annual bluegrass competition. Traffic control, moderate irrigation frequency, clipping removal, and low to intermediate nitrogen rate are recommended for the maintenance of acceptable turfgrass quality and playability, and the minimized annual bluegrass competition