Published April 11, 2026 | Version 1.0.0

Stand Density Index (SDI), Maximum Stand Density Index (SDImax), and Relative Density (RD) 30×30 m rasters for the continental United States based on TreeMap 2020

Description

This dataset provides wall-to-wall 30m resolution rasters for three forest size-density metrics across the continental United States:

i) Stand Density index (SDI; trees per hectare)

ii) Maximum Stand Density Index (SDImax; trees per hectare)

iii) Relative Density (RD; unitless ratio).

The raster products were developed from the publicly available TreeMap 2020 dataset (Zimmer et al. 2025, https://doi.org/10.2737/RDS-2025-0031) which spatially predicts forest attributes.  The forest size-density metrics were developed using publicly available plot and subplot Forest Inventory and Analysis (FIA) data following the methodology described in Chivhenge et al. (2025) (https://doi.org/10.1038/s41597-025-06012-6). This dataset is as a result of intergation of field based measurements and spatial modelling to produce wall-to-wall metrics of forest size densities. 

Files

SDI_2020.zip

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Additional details

Funding

U.S. National Science Foundation
IUCRC Phase III at University of Maine: Center for Advanced Forestry Systems (CAFS) 1915078
U.S. National Science Foundation
Collaborative Research: E-RISE RII: Enhancing Maine Forest Economy, Sustainability, and Technology Ecosystem To Accelerate Innovation 2416915
United States Department of Agriculture
United States Department of Agriculture (USDA) Sustainable Agricultural Systems (SAS) Award 2023-68012-38992

References

  • Chivhenge, E., Weiskittel, A.R., Woodall, C.W. et al. Geospatial Estimation of Forest Relative Density for Carbon Stewardship Decision Support across the Continental US. Sci Data 12, 1728 (2025). https://doi.org/10.1038/s41597-025-06012-6
  • Zimmer, S. N. et al. TreeMap 2020 CONUS: A Tree-Level Model of the Forests of the Conterminous United States circa 2020. https:// doi.org/10.2737/RDS-2025-0031 (2025).