Environmental data
All data (table 1) was downloaded in raster format and data for each location of the IUFRO population was extracted using the Point Sampling Tool in qGIS (Jurgiel, 2020; QGIS.org, 2022). Climatic data was downloaded from worldclim.org (Fick & Hijmans, 2017). This data consisted of readings from 1970-2000 with a raster resolution of 1km2. Annual snow cover data was obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite for the years 2000-2020 (Hall et al., 2006). Soil data were obtained from the Unified North America Soil Map which is a combination of soil mapping from Canada and global soil maps (Liu et al., 2014). Topographical maps were obtained from United States Geological Survey (USGS) eros (EROS, 2010). Forest fire risk maps were obtained from Genonode CSIRO (GFDRR, 2022). Data for each location of the IUFRO population is made available as a supplemental table (Supplementary table 1)