Optimal Management Practices for Kikuyugrass Quality and Playing Conditions.

Kikuyugrass (Pennisetum clandestinum Hochst. ex Chiov.) is considered either an invasive weed or the desired species on many golf courses and other turf areas along coastal and inland California.  As part of a comprehensive project aimed at Kikuyugrass improvement and management, a field study was initiated in 2011 in Riverside, CA to identify cultural and chemical practices that are most important for producing quality turf and optimal playing conditions on golf course fairways. The cultivar ‘Whittet’ was established from sod on a Hanford fine sandy loam.  A two-level, five-factor factorial design was used to evaluate mowing frequency (three vs. six times/wk), verticutting (one vs. three times/yr), trinexapac-ethyl (0 vs. 0.8 L/ha biweekly), nitrogen (98 vs. 196 kg/ha/yr), and fungicide treatment (0 vs. monthly applications according to disease activity).  Turf quality was assessed visually and by normalized difference vegetation index (NDVI).  Turf firmness and ball roll were measured with a Clegg Soil Impact Tester (2.5 kg hammer Gmax) and Stimpmeter, respectively. Shoot density and organic matter were evaluated twice per year.  Results of this study will allow Kikuyugrass managers to choose and implement the most effective and economical practices for optimal turf health and playability.