** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** WESTERN US FOREST PRODUCTIVITY IS LIMITED BY MOISTURE AND NUTRIENT RESOURCES. WE PROPOSE TO ALLEVIATE THESE LIMITATIONS AND CHARACTERIZE ECOLOGICAL PROCESSES WITHIN FORESTS GROWING AT NEAR MAXIMUM PRODUCTIVITY AT WATER RECLAMTION FACILITIES. WE WILL OPORTUNISTICALLY STUDY ACQUISITION AND IMMOBILIZATION OF SUPPLIED RESOURCES BY VEGETATION AND EXAMINE SOIL NUTRIENT CYCLING. HOWEVER, THERE IS CONCERN THAT FOREST WATER RECLAMATION FACILITIES LEAK NUTRIENTS THAT DEGRADE SURFACE WATER QUALITY. SO WE WILL ALSO FOCUS ON CHARACTERIZNG SOIL HYDRAULIC AND BIOLOGICAL PROCESSES THAT LEAD TO NUTRIENT LEACHING. TWO EXPERIMENTS ARE INCLUDED: A TIME-SERIES OF FACILITIES THAT HAVE OPERATED FROM 4 TO 40 YEARS, AND A RATE STUDY THAT INCLUDES PLOTS TREATED WITH A RANGE OF WASTEWATER APPLICATION RATES PLUS A WATER-ONLY TREATMENT THAT SEPARATES EFFECTS OF NUTRIENTS FROM WATER. WE WILL MONITOR STAND GROWTH RESPONSE AND NUTRIENT UPTAKE, MEASURE DRAINAGE, MODEL WATER BUDGETS, QUANTIFY NUTRIENT LEACHING, DETERMINE N TURNOVER, AND CHARACTERIZE SHIFTS IN MICROBIAL COMMUNITY STRUCTURE AND FUNCTION. WE WILL USE TREE-RING ANALYSIS AT THE TIME-SERIES FACILITIES TO MEASURE HISTORIC FOREST GROWTH AND PRODUCTIVITY. THIS INTERDICIPLINARY PROJECT PROVIDES PROCESS-LEVEL ASSESSMENT OF PRODUCTIVITY POTENTIAL AND SCALES TO BROAD SPATIO-TEMPORAL ASSESSMENT OF RESPONSES AMONG REGIONAL FACILITIES. WE COMBINE TECHNOLOGICALLY ADVANCED TOOLS TO ASSESS THIS EMERGING FOREST MANAGEMENT APPROACH FOR IMPROVING PRODUCTIVITY, SOIL HEALTH, AND ECOSYSTEM SERVICES. RESULTS FROM THIS PROJECT WILL BE ESPECIALLY RELEVANT TO PROGRAM GOALS OF UNDERSTANDING BIOGEOCHEMICAL PROCESSES AFFECTING FOREST PRODUCTIVITY WHILE IMPROVING SOIL HEALTH. OUTCOMES WILL PROTECT ENVIRONMENTAL QUALITY AND SUPPORT DEVELOPMENT OF THE REGION'S RURAL ECONOMY.