GRASSLANDS REPRESENT THE LARGEST AGRICULTURAL LAND USE IN THE UNITED STATES (US) AND THOSE WITHIN THE EASTERN US ACCOUNT FOR 40% OF US COW-CALF OPERATIONS. HOWEVER, EASTERN FORAGE PRODUCTION RELIES HEAVILY ON A COOL-SEASON GRASS, TALL FESCUE (TF). CONSEQUENTLY, SUMMER PRODUCTIVITY IS IMPAIRED LEADING TO OVERGRAZING AND PASTURE DEGRADATION, A PROBLEM EXACERBATED BY THE RECENT PATTERN OF REPEATED SEVERE DROUGHTS, HEAT, AND FLOODS. FURTHERMORE, TF HAS A FUNGAL ENDOPHYTE THAT NEGATIVELY IMPACTS CATTLE, ESPECIALLY DURING SUMMER, LEADING TO $2 BILLION IN ANNUAL FARM LOSSES. A NEW PRODUCTION MODEL IS NEEDED THAT IMPROVES PRODUCTIVITY AND ECOSYSTEMS HEALTH FOR EASTERN GRASSLAND AGROECOSYSTEMS. OUR GOAL IS TO DEVELOP A MODEL THAT REALIGNS CURRENT FORAGE PRODUCTION TO MORE CLOSELY MATCH THE HISTORICAL, ECOLOGICAL DOMINANCE OF WARM-SEASON (C4) GRASSES WITHIN EASTERN GRASSLANDS. USING NATIVE C4 SPECIES WITH PROVEN ADAPTABILITY TO EXTREME CLIMATE CONDITIONS AND HIGH ANIMAL PRODUCTIVITY WILL IMPROVE SYSTEM RESILIENCE WHILE MAKING IMPORTANT CONTRIBUTIONS TO SOIL HEALTH AND WATER BALANCES.