The AT_Summary.zip file contains all code and data used in our 2019 analysis of the status and trends in forest attributes along the Appalachian National Scenic Trail and surrounding lands. This document is intended to provide a brief description of our analyses, and description of contents of AT_Summary.zip. Contact Hunter Stanke at with questions.

Analysis Description

The goal of these analyses is to assess the status and trends in forest condition along the AT and neighboring lands. Specifically, we estimate the following attributes within ecoregion subsections which intersect the AT:

  1. Live tree abundance
    • TPA, BAA, biomass, and carbon by species
  2. Species diversity of live trees
    • Shannon’s diversity, eveness, and richness
  3. Tree vital rates
    • Annual diameter, basal area, and biomass growth by species
  4. Forest demographic rates
    • Annual recruitment, mortality, and harvest totals and rates by species
  5. Regeneration abundance
    • TPA of regenerating stems (<5" DBH) by species and size-class
  6. Snag abundance
    • TPA, BAA, biomass, carbon, relative fraction
  7. Down woody debris abundance
    • Volume, biomass, and carbon by fuel class
  8. Invasive Plant abundance
    • % cover by species
  9. Stand structural stage distributions
    • % area in pole, mature, and late stage forest

We used the rFIA package to estimate all forest attributes described above (see at_script.R for code). We accessed subsets of the public Forest Inventory and Analysis database on 10 October 2019 for the following states: CT, GA, ME, MD, MA, NH, NJ, NY, NC, PA, TN, VT, and VA. We produced estimates for each FIA reporting year which was common among all states included in the analysis. For most attributes we produced estimates for all years between 2005 and 2016, with the exception of 2008. For down woody debris related attributes, estimates could only be produces for years 2010, 2014, 2015, and 2016.

FIA data was not available for each ecoregion subsection defined by the ecoregion/at_ecoSub.shp shapefile. Attributes of ecoregions where FIA data was unavailable were preserved in results files (see results/) although estimated attributes are listed as NA for these rows.


File structure