Development and Evaluation of Cold Hardy Bermudagrass for Putting Greens.

Bermudagrass is experiencing increased use on golf course putting surfaces in Oklahoma and other transition zone states. Compared to creeping bentgrass greens, bermudagrass offers a more economical playing surface for lower budget golf courses. Benefits of bermudagrass include higher drought resistance, less incidence of diseases such as large brown patch, dollarspot, basal anthracnose, pythium root and crown rot, and less summer stand loss due to anaerobic soil conditions. The golf industry demands further improvements in bermudagrasses’ late-season color retention, winter hardiness, and a reduction in the use of protective winter covers. During the last 10 years we selected from over 30 bermudagrass lines that tolerated 6.4 mm mowing while remaining unprotected by covers during winter. The purpose of this study was to evaluate seven of our promising final stage experimental bermudagrass lines against the golf industry standards ‘Champion Dwarf’, ‘Mini-Verde’, ‘TifEagle’ and ‘Tifgreen’ for performance under putting green conditions at Stillwater, OK. Statistical differences in putting surface establishment rate, visual quality, green speed, and late-season color retention were found in the trial. Three improved lines were identified to advance to 2013 testing in the National Turfgrass Evaluation Program putting green trial to be conducted across the southern US. At the start of second growing season, biweekly trinexapac-ethyl (Primo Maxx^TM) application at a rate of 3oz/ac was introduced as an evaluation factor to assess its effect on seed head expression, ball speed, color, qualityand scalping resistance of all entries.