Technical Abstract: This study assessed the establishment and winter injury potential of several warm-season grass species under irrigated conditions in semi-arid environments in the Intermountain USA during 2005 and 2006. Cultivars representing seven warm-season grass species and three cool-season grass species - six cool-season grass species were evaluated at two irrigated, high-elevation locations. Some warm-season grass species, including switchgrass, showed potential for production in these environments based on favorable performance with cool-season checks for initial and second year stand frequency and establishment year biomass production. All the warm-season grasses received greater winter injury than did the cool-season checks, creating concern about the persistence of warm-season grasses in these environments. However, the increased winter injury did not correspond to decreased stands of the warm-season grasses in the subsequent year. Thus, warm-season grass production for biomass may have potential in high-elevation, irrigated settings.