GRASSLANDS PROVIDE KEY ECOSYSTEM SERVICES IN SUPPORTING LIVESTOCK PRODUCTION THROUGH RANCHING; HOWEVER, THE SUSTAINABILITY OF THESE SERVICES IS THREATENED BY VARIABILITY IN ENVIRONMENTAL CONDITIONS ASSOCIATED WITH CLIMATE CHANGE. SHIFTS IN ENVIRONMENTAL CONDITIONS WITH CLIMATE CHANGE ARE PREDICTED BROADLY ACROSS THE US, WITH BOTH SUSTAINED PATTERNS OF DROUGHT AND INCREASES IN EXTREME CLIMATE EVENTS SUCH AS HEATWAVES OR FLOODS. THESE CHANGING CONDITIONS COMPLICATE LAND MANAGEMENT FOR LIVESTOCK PRODUCTION DUE TO THE UNCERTAINTIES AROUND PREDICTING AVAILABLE FORAGE FOR GRAZING. GRASSLAND PRODUCTIVITY CAN BE HIGHLY DYNAMIC WITH CHANGES IN PRECIPITATION, AND THEREFORE MANAGEMENT PRACTICES THAT PROMOTE ECOSYSTEM RESILIENCE UNDER VARIED CONDITIONS IS ESSENTIAL FOR MAINTAINING RANCHING INDUSTRY.MANAGEMENT PRACTICES FOCUSED ON GRASSLAND BIODIVERSITY HAVE SHOWN THE IMPORTANCE OF HIGH NUMBERS OF PLANT SPECIES CO-EXISTING TO REDUCING THE CONSEQUENCES OF DROUGHT ON PRODUCTIVITY, HOWEVER, LESS IS UNDERSTOOD ABOUT THE MECHANISMS ENABLING THE BENEFITS OF THIS CO-EXISTENCE. THIS EXPERIMENT AIMS TO EVALUATE THE IMPORTANCE OF PLANT SPECIES INTERACTIONS, INCLUDING COMPETITION AND FACILITATION, AS MECHANISMS FOR PREDICTING GRASSLAND CHANGES IN PRODUCTIVITY IN RESPONSE TO EXTREME DROUGHT. RESEARCHERS WILL APPLY AN EXPERIMENTAL DROUGHT AMONG GRASSLANDS COMPRISED OF COMMUNITIES WITH DIFFERING LEVELS OF SPECIES INTERACTIONS; TAKING ADVANTAGE OF FACILITIES AND SITES ALREADY WELL UNDERSTOOD AT THE CEDAR CREEK SCIENCE RESERVE IN MINNESOTA TO TEST NEW HYPOTHESES. ADDITIONALLY, THE RESEARCH WILL PROVIDE KEY RESEARCH MANAGEMENT TRAINING FOR THE PROJECT DIRECTOR, WHILE ALSO OFFERING OPPORTUNITIES FOR UNDERGRADUATE STUDENT PROJECTS, AND KEY OUTREACH OPPORTUNITIES FOR VISITORS AT THE CEDAR CREEK FIELD STATION. FINDINGS FROM THE EXPERIMENT WILL BE USEFUL TO A RANGE OF STAKEHOLDERS INCLUDING LAND MANAGERS AND AGENCIES EXAMINING CHANGES IN RANGELAND USE UNDER FUTURE CONDITIONS OF CLIMATE CHANGE.