DOI: 10.5061/dryad.bnzs7h4hh
title: The natural ‘exclosure effect’ and tree regeneration following post-windstorm salvage logging

description: Understanding the influence of post-disturbance forest management on tree
 regeneration is critical for assessing ecosystem recovery and guiding
 future responses. In particular, the influx of elevated coarse woody
 material (CWM) following wind disturbance, if left in situ, may impede
 herbivore access, thereby protecting saplings from browsing damage through
 a natural ‘exclosure effect.’In 2013, a tornado in northcentral Maine, USA
 and subsequent salvage logging operations created three clear ‘treatments’
 for evaluation of the exclosure effect: blowdown, blowdown plus salvage
 logging, and an undamaged control. Nine years post-tornado, we inventoried
 tree regeneration within these treatments to evaluate differences in
 sapling abundance, species composition, size structure, and browsing
 intensity. We also inventoried CWM, including the height above forest
 floor.Results revealed significant differences in sapling composition and
 browsing intensity among treatments. The salvage treatment had the highest
 proportion of browsed saplings (56 ± 28%; mean ± standard error), followed
 by the control (9 ± 10%) and blowdown (5 ± 8%). Blowdown had by far the
 greatest mean (50 ± 9 cm) and average maximum (169 ± 43 cm) heights for
 CWM. Binomial generalized linear models revealed that browsing probability
 was a function of mean CWM height and an interaction between sapling
 density and proportion of sapling hardwoods. Thus, browsing damage was
 less likely in plots with greater CWM heights and more likely in plots
 with greater sapling density and more hardwood
 saplings. Synthesis and applications: This study furthers our
 understanding of ecosystem recovery following blowdown and salvage
 logging. Results suggest that salvage logging created important
 differences in CWM abundance and height distribution, when compared to
 un-salvaged areas, and that these differences in turn altered sapling size
 structure and browsing intensity. These findings highlight the potential
 long-term effects of successive disturbances, as the differences evident
 in these early stages may persist for decades or longer. Importantly, we
 provide evidence of the exclosure effect, suggesting that CWM retained in
 the un-salvaged area protected saplings from moose browsing. Thus, in
 post-disturbance areas where browsing threatens regeneration, we recommend
 that managers consider retaining CWM to serve as a natural exclosure.
description: # The Natural ‘Exclosure Effect’ and Tree Regeneration Following
 Post-Windstorm Salvage Logging
 This dataset contains the
 coarse woody material (CWM) and sapling data analyzed for this manuscript.
 Details on methods and codes are located in the metadata sheets of the
 dataset. Additional details about the methodology can be found in the
 manuscript. ## Description of the data and file structure Data are sorted
 among two sheets, one containing coarse woody material data (CWM) and the
 other containg sapling data. The CWM data sheet lists the treatment, plot
 ID, transect direction, species (if known), diameter (taken using
 calipers), height (to midpoint), and decay class (five-class scale). The
 sapling data sheet lists treatment, plot ID, transect direction, species,
 browse (presence/absence), sapling diameter size class and total (sum of
 size class rows). Species codes are provided on a separate sheet and
 metadata tabs provide additional details. ## Sharing/Access information
 Contact the corresponding author for additional details about use of this
 dataset. ## Code/Software These data were analyzed in R, code avaliable
 upon request from the corresponding author.