DOI: 10.5061/dryad.dr48cf6
title: Data from: Soil chemistry, and not short-term (1-2 year) deer exclusion, explains understory plant occupancy in forests affected by acid deposition

description: The loss of species diversity and plant community structure throughout the
 temperate deciduous forests of North America have often been attributed to
 overbrowsing by white-tailed deer (Odocoileus virginanus). Slow species
 recovery following removal from browsing, or reduction in deer density,
 has been termed a legacy effect of past deer herbivory. However,
 vegetation legacy effects have also coincided with changes to soil
 chemistry throughout the northeastern United States. In this paper, we
 assess the viability of soil chemistry (i.e. pH, extractable nutrients,
 and extractable metals) and other factors (topography, light, overstory
 basal area, and location) as alternative explanations for a lack of
 vegetation recovery. We compared the relative effects of soil chemistry,
 site conditions, and short-term (1-2 year) deer exclusion on
 single-species occupancy probabilities of 10 plant taxa common to
 oak-hickory forests in central Pennsylvania. We found detection for all
 modeled species was constant and high (p &gt; 0.65), and occupancy
 probability of most taxa was best explained by at least 1 soil chemistry
 parameter. Specifically, ericaceous competing vegetation was more likely
 to occupy acidic (pH &lt; 3.5), base cation poor (K &lt; 0.20
 cmolc/kg) sites, while deer-preferred plants were less likely to occur
 when soil manganese exceeded 0.1 cmolc/kg. Short-term deer exclusion did
 not explain occupancy of any plant taxon, and site conditions were of
 nominal importance. This study demonstrates the importance of soil
 chemistry in shaping plant community composition in the northcentral
 Appalachians, and suggests soil as an alternative, or additional,
 explanation for deer vegetation legacy effects. We suggest that the
 reliance on phyto-indicators of deer browsing effects may overestimate the
 effects of browsing if those species are also limited by unfavorable soil
 conditions. Future research should consider study designs that address the
 complexity of deer forest interactions, especially in areas with complex
 site-vegetation histories.
description: Understory plant cover
 data 2014Understory plant data by
 percent cover, average height, and count for 24 sites across Bald Eagle
 and Rothrock state forests in central Pennsylvania. See
 Vegetation_Metadata_2014.csv for specific column descriptions and data
 formatting.Cover_Data_2014.csvSeedling_Data_2014Understory tree seedling data (&lt;1 inch dbh) by height class in Rothrock and Bald Eagle state forests in central Pennsylvania. See Vegetation_Metadata_2014.csv and Species_Code_List.csv for specific column descriptions and data formatting.Tree_Data_2014Overstory tree measurements (&gt;=5" dbh) at 24 sampling sites at Rothrock and Bald Eagle state forests in central Pennsylvania. See Vegetation_Metadata_2014.csv and Vegetation_Metadata_2014.csv for specific column descriptions and data formatting.Soils_Data_2014Soil nutrient data for both organic and mineral soil horizons at 24 sites in Rothrock and Bald Eagle state forests in central Pennsylvania. See Soils_Metadata_2014.csv for descriptions of each column, including extraction methods (Kellogg Soil Science Laboratory, Lincoln, Nebraska, USA).Soils_Metadata_2014Detailed descriptions of variables in Soils_Data_2014.csvSpecies_Code_List_2014List of species names for abbreviation codes used in Tree_Data_2014.csv, Seedling_Data_2014.csv, and Cover_Data_204.csvVegetation_Metadata_2014Detailed descriptions of columns and data formatting used in Cover_Data_2014.csv, Seedling_Data_2014.csv, and Tree_Data_2014.csv