There is interest in the Northern Great Plains to use warm-season grasses for extending the "green period" for mid- and late-summer grazing and to increase species' diversity in the revegetation of deteriorated rangelands, mineland reclamation, and conservation practices applied through farm bill programs. The Wayne Berry field evaluation planting was established in May 1994, on a dryland site in east-central Montana, to study the adaptation, performance, and use of new native warm-season pasture plants in comparison to commonly used species/cultivars. Twenty-two accessions of seven warm-season grasses plus three different mixtures of selectd warm season entries were planted in 2 acre blocks. The east end of each block was cross-seeded with Astragalus cicer, Atriplex X aptera, Medicago sativa, Onobrychis vicifolia, and Sanguisorba minor. All plots were monitored for plant adaptation, grazing preference and utilization, and cattle performance over 9 years. The top performing entries were Panicum virgatum, Andropogon hallii, Schizachyrium scoparium, Bouteloua curtipedula, and Bouteloua gracilis. Results showed that the warm-season cultivars were slow to establish, but adapted to the area, and the warm-season species could increase plant diversity and provide late summer grazing. Cattle seemed to prefer and utilize the most immature entries during each late summer grazing event, regardless of cultivar or species. Andropogon gerardii, Bouteloua curtipedula, and Bouteloua gracilis were preferred at all phenology stages and the legume mixtures increased livestock preference. As a result of this research, warm-season grasses are currently being recommended and used in eastern Montana native plantings.