DOI: 10.7267/r207tx72t
title: Northern Yellowstone aspen sapling data collected 2020-2021
title: Supporting data for publication: Painter, L.E.; R.L. Beschta; W.J. Ripple. 2023 in press. Bison alter the northern Yellowstone ecosystem by breaking aspen saplings. Ecology and Evolution.

description: A table containing data from random sampling plots in 87 randomly located aspen stands in northern Yellowstone, repeating measurements by Painter et al. (2014). Stands were relocated using GPS coordinates from 2012. Each stand contained one plot 2x30 m, extending from the live, dead or fallen tree nearest the GPS location towards the centroid of the stand. Data include number of saplings (&gt;2 m tall and &lt;=5 cm dbh), number of broken saplings (.2 cm diameter at 0.5 m height) and stripped, girdled saplings. Also included are fecal pile densities of bison and elk counted in two 2x50 m plots adjacent to and about 10 m from the stand, in xeric grassland or forest edge substrate. Mesic meadows or wet locations were avoided due to low likelihood of scat detection. Scat plots were not placed within the aspen stands for the same reason, many were wet or dense with vegetation so fecal piles are unlikely to persist or be detected.
description: 1. Description of methods used for collection/generation of data: In the northern ungulate winter range of northern Yellowstone National Park, we visited 87 aspen stands that had been randomly selected and sampled in previous studies in 1997-98 and 2012 (see Painter, L.E., R.L. Beschta, E.J. Larsen, and W.J. Ripple. 2014. After long-term decline, are aspen recovering in northern Yellowstone? Forest Ecology and Management 329:108-117.) A single sampling plot 2x30 m began at the live, standing dead, or fallen aspen tree closest to the GPS locations recorded in 2012, and extending toward the centriod of the stand. We recorded the number of aspen saplings (&gt;2 m tall and &lt;=5 cm diameter-at-breast-height, dbh), the number of dead saplings stripped of bark and girdled, and the number of broken sapling stumps (&gt;2 cm in diameter at 0.5 m height). We also recorded the number of young aspen trees (6-20 cm dbh). We estimated density of elk and bison fecal piles in two belt transect plots 2x50 m, placed about 10 m from the stand and spaced 10 m apart, in the nearest xeric grassland or forest edge. Mesic grassland was avoided due to the low likelihood of scat persistence or detection in this substrate.
description: TABULAR DATA-SPECIFIC INFORMATION FOR: Painter2023_BisonAspenDataSupplement.csv 1. Number of variables: 10 2. Number of cases/rows: 87 Column definitions for Table S1, Aspen plot data 2020-21 A sapling is defined as a young aspen &gt;2 m tall and &lt;=5 cm diameter-at-breast-height (dbh). COLUMN HEADINGS EXPLANATION 1. GPS.ID Plot GPS ID when plots were sampled in 2020-21. 2. Sector The study area was divided into three sectors, West, Central, and East. 3. Year Year data were collected 4. n5cm Count of live aspen saplings in plot 5. n6to20 Count of live young trees 6 to 20 cm dbh in plot 6. Broken Count of broken aspen &gt;2 cm diameter at 0.5 m height 7. Stripped Count of saplings dead from bark stripping and girdling 8. n5cmAll Total number of saplings (n5cm + Broken + Stripped) 9. Bison.100m2 Bison fecal pile density per 100 m^2, in 2x100 m plot near the aspen plot 10. Elk.100m2 Elk fecal pile density per 100 m^2, in 2x100 m plot near the aspen plot