Turf Quality of Minimally Irrigated Warm and Cool Season Grasses.

Growing attention is being focused on the amount of water used to irrigate turf areas in the Southwestern United States, and many municipalities are now implementing water conservation strategies. For this reason it is increasingly important to determine minimum irrigation requirements to maintain turfgrass of acceptable quality. In a study conducted in 2007 at New Mexico State University 22 warm season grasses were irrigated at 30%, 40%, and 60% of reference evapotranspiration (refET) and 19 cool season turfgrasses at 70%, 60% and 50% refET by means of a subsurface drip irrigation system. From June to September of 2007, bermudagrass (Cynodon dactylon L.) cultivars Celebration, Princess 77, SWI 1044, Tifsport, and Yukon, and seashore paspalum (Paspalum vaginatum Swartz) cultivars SeaIsle 2000 and Supreme performed best of the warm season grasses at 30% refET and exhibited turf quality ratings of 7 or higher. Cool season tall fescue (Festuca arundinacea Schreb.) cultivars Endeavor and Silverado II and hard fescue (Festuca longifolia Thuill.) cultivar Hardtop performed best at 50% refET with quality ratings of 6 during the summer of 2007. Fourteen warm season grasses exhibited an acceptable turf quality of 6 or higher at the lowest irrigation level, whereas only 6 cool season grasses reached quality levels of 6 or higher even with the highest irrigation (70% refET) amounts. Based on our results, warm season grasses such as bermudagrass and seashore paspalum appear to be the logical choices for the desert Southwest if irrigation during the summer is restricted to bare minimum amounts.