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Understanding i-Tree: summary of programs and methods

Informally Refereed

Abstract

i-Tree is a suite of computer software tools developed through a collaborative publicprivate partnership. These tools are designed to assess and value the urban forest resource, understand forest risk, and develop sustainable forest management plans to improve environmental quality and human health. This report provides details about the underlying methods and calculations of these tools, as well their potential limitations. Also discussed are the history of i-Tree, its future goals, and opportunities to facilitate new science and international collaboration.

This report was revised in 2021 and is available at https://doi.org/10.2737/NRS-GTR-200-2021. Revisions include updates to procedures and values.

The appendixes can be accessed through the links below.

Appendix 1: i-Tree Staff and Collaborators

Appendix 2: i-Tree Links

Appendix 3: Shading Coefficients

Appendix 4: Conversion Factors for Leaf Area to Biomass

Appendix 5: Conversion Factors for Shrub Volume to Biomass

Appendix 6: Invasive Plant Species

Appendix 7: Compensatory Value of Trees

Appendix 8: Average Energy Costs

Appendix 9: Energy Conservation Estimates for Buildings in non-U.S. Countries

Appendix 10: New Biomass Equations

Appendix 11: Wood Density Values

Appendix 12: Volatile Organic Compounds (VOC) Emission Rates

Appendix 13: Equations for Tree Height, Crown Height, and Crown Width

Appendix 14: Partial List of Publications Referencing i-Tree Tools

Keywords

air pollution removal, carbon sequestration, computer modeling, economic valuation, ecosystem services, forest inventory, forest risk, urban forestry

Citation

Nowak, David J. 2020. Understanding i-Tree: summary of programs and methods. General Technical Report NRS-200. Madison, WI: U.S. Department of Agriculture, Forest Service, Northern Research Station. 100 p. [plus 14 appendixes]. https://doi.org/10.2737/NRS-GTR-200.
Citations
https://www.fs.usda.gov/research/treesearch/61514