Forest Ecosystem Monitoring Cooperative(802) 656-0683femc@uvm.eduwww.uvm.edu/femc705 Spear StreetSouth BurlingtonVermont05403United States of AmericaUnited States Department of Agriculture (USDA), Forest Service leadFederal Forest Inventory and Analysis Data for the NortheastA summary of the latest USDA Forest Inventory and Analysis data for the Northeast. The network of randomly distributed inventory plots are designed to capture broad temporal changes in the condition of the nation’s forest resource. Spatial coverages of species distribution, extent of forest cover and biomass compliment the yearly data summaries to capture an unbiased estimated of the northeastern forests.Federal Forest Inventory and Analysis Data for the NortheastNevinsMatthiasforest healthforest inventorynortheastern forestsforest coverseedlingVT FIA Derived Tree Species Diversity 1997-01-01Using the USFS Forest Inventory and Analysis Program population estimate data on Phase 2 plots accessed via the FIA Datamart1, we tallied the number of trees (≥5 in diameter) per species to compute a Shannon-Weiner Diversity Index calculation (see equation below). The first available data year was 1997. We divided all sampled trees into 5 inch classes and tallied the total proportion of each size class measured in the plots. To compute the annual score, we used FIA’s plot evaluation group panels to create population estimates for each year. The target for this dataset was set as the maximum value plus 10% of the range. The target was set as the upper scoring bounds (dataset maximum plus 10% of the range), and the current year is scored for where it falls between the acceptable species diversity thresholds of 1.5 and 3.52, scaled to be between 1 and 5.Z1384_4053_CQBOZEVMC.1384.4053mySQLDonisvitch, S (2025) VT FIA Derived Tree Species Diversity . FEMC. Available online at: https://www.uvm.edu/femc/data/archive/project/federal-forest-inventory-analysis-data-northeast/dataset/vt-fia-derived-tree-species-diversityhttps://www.uvm.edu/femc/CI4/data/archive/project/federal-forest-inventory-analysis-data-northeast/dataset/vt-fia-derived-tree-species-diversitySPCDSPCDdecimalvol_weightvol_weightdecimalYearYearint