**AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** SUB-TROPICAL TREE CROPPING SYSTEMS REQUIRE INTENSIVE MANAGEMENT, PRIMARILY DUE TO THE EXTREMELY COARSE-TEXTURED AND ORGANIC MATTER POOR SOIL. COVER CROPS ARE A COMMON METHOD TO IMPROVE SOIL HEALTH FOR ANNUAL CROPS, HOWEVER, DIFFERENT IMPLEMENTATION METHODS ARE NEEDED FOR TREE CROPS. IN ADDITION, DATA ON THE RESPONSE OF SUB-TROPICAL TREE CROP SOILS TO COVER CROPS IS LIMITED, PARTICULARLY FOR THE CONTRIBUTION OF THE SOIL MICROBIOME. SOIL HEALTH INDICATORS CAN ASSIST IN DETERMINING HOW COVER CROPS CHANGE SOIL HEALTH IN THESE SYSTEMS. HOWEVER, WHILE THERE ARE MULTIPLE SUGGESTED SOIL HEALTH INDICATORS AVAILABLE, ASSESSMENT HAS PRIMARILY OCCURRED IN TEMPERATE ANNUAL CROPS.THIS PROJECT WILL DETERMINE THE IMPACT OF COVER CROPS ON SOIL HEALTH IN SUB-TROPICAL TREE CROPS THROUGH FIELD TRIALS WITH COMMERCIAL PRODUCERS. TO ASSESS THESE IMPACTS, TRADITIONAL AND NOVEL INDICATORS OF PHYSICAL, CHEMICAL, AND MICROBIAL SOIL HEALTH COMPONENTS WILL BE UTILIZED, AND SAMPLED ACROSS DIFFERENT TIMESCALES. THIS PROJECT WILL ALSO EXAMINE THE RELATIONSHIP BETWEEN SOIL HEALTH AND THE DIVERSITY OF PLANT-GROWTH PROMOTING FUNCTIONS OF THE SOIL MICROBIOME, AS THESE MAY NOT ONLY BE CRITICAL TO SOIL HEALTH CHANGES BUT COULD ALSO SERVE AS NEW BIOLOGICAL SOIL HEALTH INDICATORS.OUR PROJECT DIRECTLY ADVANCES THE SCIENTIFIC UNDERSTANDING OF SOIL PHYSICAL AND BIOCHEMICAL PROCESSES AND INTERACTIONS BY EXAMINING THE INTERACTION OF THE SOIL MICROBIOME WITH PHYSICO-CHEMICAL FACTORS UNDER CHANGING SOIL HEALTH CONDITIONS. IN ADDITION, THE EXPLORATION OF A VARIETY OF SOIL HEALTH INDICATORS WILL ALLOW FOR THE DEVELOPMENT OF APPROPRIATE AND EFFECTIVE METHODS FOR MONITORING SOIL HEALTH CHANGES IN SUB-TROPICAL TREE CROPS.