- Freshwater resources are becoming more and more scarce worldwide, and rights to water use is becoming more competitive between stakeholders. Irrigation for agricultural purposes accounts for a large portion of freshwater usage. Using drought tolerant plant species in irrigated pastures could become a necessity in order to reduce competition for water. This study was conducted in the arid environment of eastern Oregon using twenty common perennial forage species. Five legumes, ten C3 grasses, and five C4 grasses were selected. Each species was subjected to four different irrigation treatments to determine growing season water requirements. Data was gathered by harvesting, drying, and weighing the plant material in each replication of all treatments. Average production results show that C3 grasses produced the most forage of all species groups, with production varying from 5.299 to 4.433 dry tons per acre across treatments for the first harvest. Legumes produced between 2.154 and 1.607 dry tons per acre across all treatments for the first harvest, with the highest yield occurring in a water-limited treatment. C4 grasses produced between 2.139 and 0.410 dry tons per acre for the only harvest.