2010 SOUTHEASTERN NATURALIST 9(3):435–452
Ground-layer Bryophyte Communities of Post-adelgid
Picea-Abies Forests
Sarah E. Stehn1, Christopher R. Webster1,*, Janice M. Glime2,
and Michael A. Jenkins3
Abstract - Spruce-fir forests of the southern Appalachians are threatened by the
widespread death of Abies fraseri (Fraser Fir) caused by the exotic Adelges piceae
(Balsam Woolly Adelgid). Subsequent canopy opening, due to decimation of the fir
population, has likely affected ground-layer dynamics and diversity. We sampled
bryophytes on 60 randomly selected plots within the spruce-fir zone of Great Smoky
Mountains National Park (GSMNP) using the line-intercept method (total sampling
distance of 1800 m). Our sampling revealed 97 bryophyte species (64 mosses and
33 liverworts) comprising 32 families and 60 genera on ground-layer substrates
in spruce-fir forests. Our results suggest that upwards of 20% of the bryoflora of
GSMNP can be found on ground-level substrates in the spruce-fir zone.
Introduction
The southern Appalachians, especially Great Smoky Mountains National
Park (GSMNP), are known for their diverse flora (e.g., Whittaker 1956,
1965) and fauna (e.g., Petranka 1998, Watson et al. 1994). The broad elevation
range (266–2024 m) of the mountains allows for the existence of many
habitats, and the area has historically served as a mixing point for species
with affinities to northern coniferous forests (White and Renfro 1984),
the eastern Coastal Plain, and even the tropics (Sharp 1939). Occupying
the highest peaks, the spruce-fir (Picea-Abies) zone has been noted for its
unique flora (White and Renfro 1984). Compared to northern Appalachian
spruce-fir, GSMNP’s warmer climate and geographic location allow it to
support many exceptional disjuncts and endemic species (White 1984).
Additionally, the geologic history of the southern Appalachians as a refuge
for species retreating from glaciation, and the status of the spruce-fir zone
as a relict boreal system over the past 18,000 years (Delcourt and Delcourt
1984) have contributed to this unique composition.
However, over the past 30 years, the overstory of spruce-fir forest in the
southern Appalachians has undergone significant change due to the widespread
death of Abies fraseri (Pursh) Poir. (Fraser Fir) caused by the invasion
of the exotic Adelges piceae Ratz. (Balsam Woolly Adelgid [BWA]) (e.g.,
1School of Forest Resources and Environmental Science, Michigan Technological
University, Houghton, MI 44931. 2219 Hubbell Street, Houghton, MI 44931. 3Department
of Forestry and Natural Resources, Purdue University, West Lafayette, IN
47907. *Corresponding author - cwebster@mtu.edu.
436 Southeastern Naturalist Vol. 9, No. 3
Jenkins 2003, Nicholas et al. 1992, Smith and Nicholas 1998). In addition to
adelgid-caused fir mortality, chronic acid deposition (Hain and Arthur 1985),
climatic stress (Johnson et al. 1986), and accelerated rates of natural disturbance
(Busing and Pauley 1994) have been hypothesized to have negatively
affected the survival of both Picea rubens Sarg. (Red Spruce) and remaining
Fraser Fir. Change in overstory condition, as well as direct and indirect
effects associated with acid deposition and climatic stress, have also likely
impacted understory species in these forests (e.g., DeSelm and Boner 1984,
Gilliam 2006, Johnson and Smith 2005).
Often overlooked in vegetation studies due to their small size and difficultly
in identificaton, bryophytes may nonetheless have potential value in
assessing ecological condition (Frego 2007, Fritz et al. 2009), biodiversity
(Smith et al. 2008), and air pollution levels (Gilbert 1968, Gramatica et
al. 2006, Uyar et al. 2007). Bryophytes have previously been shown to respond
to changes in light (e.g., Hoddinott and Bain 1979), acid deposition
(e.g., Bates 2000, Koranda et al. 2007), substrate availability (e.g., Mills
and Macdonald 2004, Rambo and Muir 1998, Shields et al. 2007), and
substrate quality (e.g., Söderström 1988); thus, it is probable that bryophytes
of the spruce-fir zone have been affected by shifts in canopy, shrub,
and herbaceous-layer cover and composition resulting from adelgid-induced
overstory mortality, as well as other factors affecting high-elevation
southern Appalachian forests.
Although significant descriptive works on bryophytes in GSMNP
spruce-fir forests do exist (Cain and Sharp 1938, Norris 1964, Schofield
1960, Smith 1984), to our knowledge, only three studies have assessed
post-adelgid bryophyte condition. Choberka (1998) quantified bryophyte
species occurring on Fraser Fir logs, Smith et al. (1991) surveyed for
bryophytes on living fir trees, and Davison et al. (1999) reported on the
condition of six bryophyte species of conservation concern. The objective
of our study was to comprehensively investigate and quantify the condition
of ground-layer bryophytes across multiple substrates in the rapidly
changing and imperiled spruce-fir zone.
Description of Study Area
All study sites were located within Great Smoky Mountains National
Park (35°35'N, 83°28'W), a 210,000-ha preserve straddling the border of
Tennessee and North Carolina (Fig. 1). The climate is classified as humid
subtropical and characterized by uniform precipitation distribution.
In the spruce-fir zone, above 1500 m, precipitation is especially high,
reaching up to 260 cm per year (NCDC 2005). Winter temperatures can
be quite low, with January high temperatures averaging 1 °C. Canopy
dominance within spruce-fir forests varies considerably with change in
elevation, and our study sites encompassed a range from 1262–1964 m
2010 S.E. Stehn, C.R. Webster, J.M. Glime, and M.A. Jenkins 437
due to the broad ecotone that exists between the spruce-fir forest type
and the northern hardwood deciduous type (Schofield 1960). At the
lower elevations (<1400 m), Red Spruce is the dominant species, with
Betula alleghaniensis Britton (Yellow Birch) and Tsuga canadensis (L.)
Carr. (Eastern Hemlock) occasionally interspersed. In the mid-elevations
(1400–1600 m), Red Spruce and Fraser Fir tend to co-dominate, with
pockets of Yellow Birch and Acer spicatum Lam. (Mountain Maple). At
the highest elevations (>1600 m), Fraser Fir is the dominant species, but,
due to impacts of the BWA, is largely missing from the overstory, and
instead often forms a thick regeneration layer in the understory. Additionally,
numerous standing snags and networks of fallen logs covering the
forest floor now characterize formerly fir-dominated sites. Fast-growing
disturbance-adapted species, including Prunus pensylvanica L.f. (Pin or
Fire Cherry), Sorbus americana Marsh. (Mountain Ash), and thickets of
Rubus canadensis L. (Smooth Blackberry), were common in stands that
have experienced heavy adelgid-related overstory mortality.
Methods
In order to quantify bryophyte community composition in post-adelgid
spruce-fir forests, we randomly located 60 plots within GSMNP using a
stratification based on overstory type in an attempt to capture the wide
range of canopy conditions representative of the spruce-fir zone and its
Figure 1. Location of 60 plots where bryophytes were sampled in Great Smoky
Mountains National Park.
438 Southeastern Naturalist Vol. 9, No. 3
ecotone with northern hardwoods (Schofield 1960). Using the NatureServe
vegetation model for GSMNP (White et al. 2003), 40 plots were selected in
areas with Fraser Fir- or spruce-fir-dominated canopies, and 20 plots were
selected in areas of Red Spruce dominance, but still in the spruce-fir zone.
Beyond this stratification and a restriction that limited plots to less than
500 but greater than 10 m from roads and trails to ensure safe access, plot
locations were random, and the sampling regime at each plot was systematic.
We sampled all selected plots over the summers (June–August) of 2007
and 2008.
At each plot, bryophyte sampling was conducted along three 20-m
transects using the line-intercept method. The line-intercept method has
been successfully used for quantitative bryophyte sampling (e.g., Hattaway
1980, Kimmerer 1994), including in spruce-fir forests (e.g., Davis 1964),
but it is important to note that due to the extremely small size of some bryophyte
species, it is probably impossible to capture the linear cover of every
bryophyte shoot that crosses the line, and those small species are likely
underrepresented. Transects were systematically positioned at 4 m, 10 m,
and 16 m from the higher-elevation end of the plot and laid perpendicular
to the slope of the plot to minimize trampling damage. Since transects were
placed systematically within randomly located plots, the amount and type
of substrate, tree, shrub, and herbaceous canopy cover, and moisture classes
encountered were purely by chance. We quantified bryophyte cover by species
and substrate along alternate meters of each transect for a total sampling
distance of 30 m at each plot. A meter stick was placed on the ground directly
under the transect to accurately measure cover when the transect tape lay
>10 cm above the ground surface. Our substrate sampling focused on those
occurring at ground-level (<50 cm) and was limited to occupied rather than
available substrates for most categories. Substrates were assigned to one
of 5 classes: (1) rock for stones and boulders (>5 cm diameter); (2) soil for
mineral soil, organic soil, and humus; (3) live wood for tree and shrub bases;
(4) litter for coniferous litter and fine woody debris (<5 cm diameter); and
(5) coarse woody debris (>5 cm diameter). Coarse woody debris (CWD) was
further classified as either hard (decay class 1 and 2) or soft (decay class 3,
4, 5) based on Jenkins et al. (2004).
We collected bryophyte species which proved difficult to identify in
the field, put them in paper envelopes, and brought them to the lab for
later identification. Because of the small size of bryophytes, it is common
for species identification to involve the use of both dissecting and
compound microscopes and thus require significant laboratory time.
Specimens were identified by the lead author under guidance of the
third author. Particularly difficult specimens and groups were later verified
by personnel at the Duke University herbarium and compared with
regional collections. Nomenclature follows Stotler and Crandall-Stotler
(1977) for liverworts (except for Riccardia jugata Schust., which fol2010
S.E. Stehn, C.R. Webster, J.M. Glime, and M.A. Jenkins 439
lows Hicks 1992) Anderson et al. (1990) for mosses (except for the genus
Sphagnum L. which follows Anderson (1990), and Hypnum fauriei
Cardot, which follows Schofield et al. [in press]). Bryophyte specimens
collected in this study are housed in the Natural History Collection (catalog
numbers 104001–104961) of Great Smoky Mountains National Park,
Gatlinburg, TN.
Results and Discussion
Our sampling quantified the distribution of 97 bryophyte species (64
mosses and 33 liverworts) comprising 32 families and 60 genera in sprucefir forests (Appendix 1). The GSMNP species list, which is likely quite
comprehensive due to previous descriptive works (Cain and Sharp 1938,
Norris 1964, Schofield 1960, Smith 1984) and ongoing All Taxa Biodiversity
Inventory (ATBI; Nichols and Langdon 2007) activities, contains 485
species; thus, we can conclude that at least 20% of the bryoflora of GSMNP
can be found on ground-level substrates in the spruce-fir zone. Species of
note include the globally imperiled liverwort Bazzania nudicaulis A. Evans,
which is endemic to spruce-fir forests of the southern Appalachians. We
found small amounts of this species at two sites (Appendix 1)—once on
a downed dead Fraser Fir and once on rock. However, given that its most
frequent habitat is the bark of living Fraser Fir, our sampling design would
not necessarily capture its distribution well. The most frequent species were
Thuidium delicatulum (Hedw.) Schimp, Tetraphis pellucida Hedw., Brotherella
recurvans (Michx.) Fleisch, and Bazzania trilobata (L.) A. Gray found
on 58, 54, 53, and 49 of 60 plots, respectively.
Our species total is comparable with other studies. Although Cain and
Sharp (1938) found 81 mosses and 45 liverworts in their classification of
bryophytic unions in GSMNP, the slightly higher number of species in their
study can easily be attributed to their inclusion of species throughout the
cove hardwood community types. Norris (1964) found 131 mosses and 76
liverworts in a detailed study on the bryoecology of the spruce-fir zone.
This high species count likely resulted from his extensive sampling on all
substrates (including those on standing live trees) and in all microhabitats,
which has been shown to best capture bryophyte diversity (McCune and Lesica
1992, Newmaster et al. 2005). Our sampling inherently included greater
sampling distance on the most frequently encountered substrates, but did not
make efforts to include all microhabitats. Our species count was higher than
the two existing post-adelgid studies, reflective of their focus on single substrates.
Smith et al. (1991) found 27 bryophyte species occurring on living
Fraser Fir trees, and Choberka (1998) documented 30 bryophytes occurring
on downed Fraser Fir logs.
Our species list is perhaps best compared to that of Schofield (1960),
which focused on variation across the spruce-fir deciduous forest ecotone.
440 Southeastern Naturalist Vol. 9, No. 3
Schofield’s sites captured a variety of canopy conditions due to natural
variation with elevation and aspect, whereas we captured this variation
as well as that induced by the effects of the BWA. Schofield’s species list
included 45 mosses, 11 of which we did not find, though no clear trend
in species loss was apparent. We did, however, find several species not
reported by Schofield (1960), including some very common mosses such
as Hypnum pallescens (Hedw.) P. Beauv. and Rhytidiadelphus triquetrus
(Hedw.) Warnst. (found on 27% of our plots) and most notably Dicranodontium
denudatum (Brid.) E. Britton, which we found on 65% of our
plots. This difference may reflect an increase in dead downed wood availability
within spruce-fir forests due to BWA effects since 1960, as we
found D. denudatum predominantly on downed wood (68.8% of noted occurrences).
Hypnum pallescens was also frequently found on downed wood
(85.3% of noted occurrences).
Figure 2. Substrate preference
of bryophyte groups:
a) liverworts and b) mosses.
Percent of total group cover
found on each substrate is
shown. CWD refers to coarse
woody debris substrates of
any decay class.
2010 S.E. Stehn, C.R. Webster, J.M. Glime, and M.A. Jenkins 441
Although our sampling did not quantify unoccupied substrate availability,
our results suggest that bryophytes occupy a variety of substrates along
the forest floor in post-adelgid spruce-fir forests. Coniferous litter supported
43.2% of the cover of bryophytes, soil 27.1%, CWD 24.6% (7.5%
on decay classes 1 and 2; 17.1% on decay classes 3, 4, and 5), rock 2.8%,
and live wood 2.3%. Mosses and liverworts exhibited similar affinities for
litter, rock, and live wood, but liverworts displayed a stronger affinity for
CWD and mosses displayed a stronger affinity for soil (Fig. 2). Growth
form and taxonomic group played a major role in elevation differences
among species (Stehn 2009). Substrate availability on the forest floor and
substrate preference of individual species (Fig. 3, Appendix 1) may become
important drivers of bryophyte community composition and cover as the
impacts of BWA-induced canopy opening continue to influence groundlayer
conditions.
Bryophyte response to another conifer pest, the exotic Adelges tsugae
Annand. (Hemlock Woolly Adelgid), which decimates Eastern Hemlock,
Figure 3. Individual species substrate preference for all species occurring on ≥100 cm
across all sampled substrates. For simplicity, cover on live wood and rock substrates
is not included. See Appendix 1 for definitions of species codes.
442 Southeastern Naturalist Vol. 9, No. 3
was catalogued in the northern Appalachians by Cleavitt et al. (2008). The
authors conducted pre-infestation surveys and revisited sites 9–11 years after
outbreak, documenting a sustained increase in bryophyte species richness
and attributing it to an increase of CWD and mineral soil substrate availability.
Comparable quantitative pre-BWA ground-layer bryophyte data are
unavailable for GSMNP, but we may expect a similar increase in richness to
have occurred based on comparisons to Schofield (1960).
Given that bryophytes have been positively linked to the regeneration
of conifers (McLaren and Janke 1996, Parker et al. 1997, St. Hilaire and
Leopold 1995), and that regeneration success of the declining conifers will
be important if spruce-fir forests of the southern Appalachians are to persist
(e.g., Busing 1996, Johnson and Smith 2005), monitoring the condition of
bryophyte communities may be integral to understanding the long-term dynamics
of this system. Our results, which quantify ground-layer bryophytes
in spruce-fir forests of GSMNP 20–30 years post-adelgid, provide an important
baseline for future bryoecology research in this imperiled forest type.
Acknowledgments
This project was made possible by funding from the Air Resource Division of the
National Park Service and the Ecosystem Science Center at Michigan Technological
University and by assistance from Student Conservation Association volunteers. We
thank Ken McFarland for his help in attaining documents at the University of Tennessee.
We thank Jon Shaw, Blanka Shaw, and Piers Majestyk for their assistance with
species identification at the Duke University Herbarium. We also express thanks to
the resource management staff at Great Smoky Mountains National Park and to field
assistants Thomas McDonough, Katri Morley, Brandon Potter, Nicole Samu, Jenny
Stanley, Meg Walker-Milani, Betina Uhleg, and Philip White, and lab assistants Jennifer
Boettger, Mike Foster, Maria Parisot, Bliss Sengbusch, and Aaron Wuori.
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2010 S.E. Stehn, C.R. Webster, J.M. Glime, and M.A. Jenkins 447
Appendix 1. Abundance of all species found along ground-layer transects in 60 spruce-fir forest plots within Great Smoky Mountains National Park. Frequency indicates
both the number of plots (n = 60) and the number of transect segments (n = 30 at each plot) where the species occurred. CWD = coarse woody debris.
% Cover on plot Substrate utilization: when present,
Frequency when present % of cover found on each substrate
# # (mean CWD CWD Live
Phylum/Order/Family Species code Species Plots Seg ± 95% CI) -hard -soft Litter wood Rock Soil
Bryophyta
Bryales
Bryaceae
POHLELO Pohlia elongata Hedw. 1 1 0.03 ± 0.00 0 0 0 0 0 100.0
Mniaceae
MNIUHOR Mnium hornum Hedw. 2 3 0.18 ± 0.23 18.2 0 0 0 0 81.8
PLAGCIL Plagiomnium ciliare (Müll. Hal.) T. Kop. 7 18 0.37 ± 0.57 3.0 0 1.3 5 0 91.1
RHIZPUN Rhizomnium punctatum (Hedw.) T. Kop. 5 27 0.76 ± 0.70 0 30.4 0 0 0 69.6
Dicranales
Dicranaceae
DICRHET Dicranella heteromalla (Hedw.) Schimp. 10 20 0.61 ± 0.47 0 21.2 3.8 0 2.2 72.8
DICRASP Dicranodontium asperulum (Mitt.) Broth. 4 16 1.05 ± 1.23 6 0 0 7 65.9 21.4
DICRDEN Dicranodontium denudatum (Brid.) E. Britton 39 182 0.81 ± 0.25 10.8 58 9 1.6 2.4 17.6
DICRFUS Dicranum fuscescens Turner 28 131 0.87 ± 0.43 9.9 29.8 4.6 1.8 1.9 52.0
DICRSCO Dicranum scoparium Hedw. 31 151 1.13 ± 0.49 6.1 22.8 4.7 0.8 2.6 62.9
DICRVIR Dicranum viride (Sull. & Lesq.) Lindb. 1 3 0.60 ± 0. 10 0 0 0 0 0 0
PARALON Paraleucobryum longifolium (Hedw.) Loeske 7 18 0.27 ± 0.16 50.0 17.2 32.8 0 0 0
Leucobryaceae
LEUCALB Leucobryum albidum (Brid. ex P. Beauv.) Lindb. 2 6 0.35 ± 0.57 0 0 0 0 0 100.0
LEUCGLA Leucobryum glaucum (Hedw.) Ångstr. 4 12 0.31 ± 0.27 0 0 11 0 0 89.0
Grimmiales
Grimmiaceae
GRIMMsp Grimmia sp. Hedw. 1 2 0.36 ± 0.0 0 0 0 0 0 0 100.0
Hypnales
Brachytheciaceae
BRACDIG Brachythecium digastrum Müll. Hal. & Kindb. 1 1 0.13 ± 0.0 0 0 100.0 0 0 0 0
448 Southeastern Naturalist Vol. 9, No. 3
% Cover on plot Substrate utilization: when present,
Frequency when present % of cover found on each substrate
# # (mean CWD CWD Live
Phylum/Order/Family Species code Species Plots Seg ± 95% CI) -hard -soft Litter wood Rock Soil
BRACOXY Brachythecium oxycladon (Brid.) A. Jaeger 7 41 1.91 ± 1.78 2.0 0 17.0 0 11.9 69.0
BRACPLU Brachythecium plumosum (Hedw.) Schimp. 3 3 0.34 ± 0.39 0 71.0 0 0 29.0 0
BRACRUT Brachythecium rutabulum (Hedw.) Schimp. 1 1 0.13 ± 0.00 0 0 0 0 100.0 0
BRACHsp Brachythecium sp. Schimp. in B.S.G. 4 17 0.44 ± 0.61 17.0 0 83.0 0 0 0
BRYHGRA Bryhnia graminicolor (Brid.) Grout 1 6 0.90 ± 0.00 0 22.2 77.8 0 0 0
BRYHNOV Bryhnia novae-angliae (Sull. & Lesq.) Grout 10 40 1.23 ± 0.45 0.8 0 40.1 0 0.5 58.5
STEESER Steerecleus serrulatus (Hedw.) H. Rob. 37 163 0.72 ± 0.21 3.9 6.8 82.4 1.6 0.4 5.0
Hylocomiaceae
HYLOUMB Hylocomiastrum umbratum (Hedw.) Schimp. 11 34 0.81 ± 0.43 1.5 13.8 32.1 0 0 52.6
HYLOSPL Hylocomium splendens (Hedw.) Schimp. 37 261 3.39 ± 1.13 1.7 0.9 8.6 0 0 88.9
LOESBRE Loeskeobryum brevirostre (Brid.) Fleisch. 11 54 3.08 ± 0.16 2.8 7.1 0.6 0 21.1 68.4
PLEUSCH Pleurozium schreberi (Brid.) Mitt. 7 33 1.97 ± 0.29 0 5.8 1.2 0 0 93.0
RHYTSQU Rhytidiadelphus squarrosus (Hedw.) Warnst. 8 32 1.65 ± 0.06 0 0 19.6 0 17.6 62.8
RHYTTRI Rhytidiadelphus triquetrus (Hedw.) Warnst. 16 74 0.98 ± 0.47 0 0 13.6 0 0 86.4
Hypnaceae
CALLHAL Callicladium haldanianum (Grev.) H.A. Crum 1 1 0.30 ± 0.00 0 0 100 0 0 0
HYPNCUR Hypnum curvifolium Hedw. 15 49 1.16 ± 0.49 26.9 44.8 18.9 0.6 7.1 1.7
HYPNFAU Hypnum fauriei Cardot 9 25 0.59 ± 0.33 7.5 26.7 65.8 0 0 0
HYPNIMP Hypnum imponens Hedw. 27 215 2.90 ± 1.16 12.4 33.0 48.2 4.9 1.4 0.1
HYPNPAL Hypnum pallescens (Hedw.) P. Beauv. 16 31 0.42 ± 0.37 31.4 53.9 2 6.9 5.9 0
HYPNPRA Hypnum pratense (Rabenh.) Koch ex Spruce 1 1 0.90 ± 0.00 0 100.0 0 0 0 0
HYPNUsp Hypnum sp. Hedw. 1 3 0.26 ± 0.00 0 0 0 100.0 0 0
ISOPMUE Isopterygiopsis muelleriana Schimp.) Z. Iwats. 1 1 0.10 ± 0.00 0 0 0 0 100 0
ISOPTEN Isopterygium tenerum (Sw.) Mitt. 7 16 0.49 ± 0.18 10.6 14.4 22.1 21.2 12.5 19.2
PLATREP Platygyrium repens (Brid.) Schimp. 6 13 0.37 ± 0.14 50.7 29.9 0 4.5 14.9 0
PSEUELE Pseudotaxiphyllum elegans (Brid.) Z. Iwats. 6 18 0.52 ± 0.27 0 14.9 39.4 0 25.5 20.2
PTILCRI Ptilium crista-castrensis (Hedw.) De Not. 15 40 1.14 ± 0.96 0 6.2 4.3 0 5.4 84.1
PYLAPOL Pylaisiella polyantha (Hedw.) Grout 12 14 0.24 ± 0.10 64 11.2 24.7 0 0 0
PYLASEL Pylaisiella selwynii (Kindb.) H.A. Crum, Steere 1 1 0.20 ± 0.00 0 0 100.0 0 0 0
& L.E. Anderson
2010 S.E. Stehn, C.R. Webster, J.M. Glime, and M.A. Jenkins 449
% Cover on plot Substrate utilization: when present,
Frequency when present % of cover found on each substrate
# # (mean CWD CWD Live
Phylum/Order/Family Species code Species Plots Seg ± 95% CI) -hard -soft Litter wood Rock Soil
Plagiotheciaceae
PLAGCAV Plagiothecium cavifolium (Brid.) Z. Iwats. 11 49 0.68 ± 0.39 0 4.0 67.0 3.5 12.0 12.8
PLAGDEN Plagiothecium denticulatum (Hedw.) Schimp. 1 2 0.13 ± 0.00 0 100.0 0 0 0 0
PLAGLAE Plagiothecium laetum Schimp. 20 50 0.28 ± 0.12 1.2 7.1 69.6 10.1 6.5 5.4
Sematophyllaceae
BROTREC Brotherella recurvans (Michx.) Fleisch. 53 789 5.65 ± 1.02 9.5 21.7 62.7 4.6 1.3 0.2
HETEAFF Heterophyllium affine (Hook.) Fleisch. 12 24 0.59 ± 0.45 53.3 31.3 11.2 0 0 4.2
PYLATEN Pylaisiadelpha tenuirostris (Bruch & Schimp.) 8 19 0.42 ± 0.23 4.0 18.0 59.4 9 10 0
W.R. Buck
SEMAADN Sematophyllum adnatum (Michx.) E. Britton 1 4 0.66 ± 0.00 70.0 30.0 0 0 0 0
SEMADEM Sematophyllum demissum (Wilson) Mitt. 2 2 0.48 ± 0.16 0 0 0 0 100.0 0
Thuidiaceae
THUIDEL Thuidium delicatulum (Hedw.) Schimp. 58 665 4.62 ± 1.21 3.9 3.4 86.5 1.8 2.0 2.3
Leucodontales
Anomodontaceae
ANOMROS Anomodon rostratus (Hedw.) Schimp. 1 1 0.30 ± 0.00 0 0 0 0 100 0
Leucodontaceae
LEUCBRA Leucodon brachypus Brid. 1 4 2.16 ± 0 10 0 0 0 0 0 0
Orthotrichales
Orthotrichaceae
ORTHOsp Orthotrichum sp. Hedw. 1 1 0.13 ± 0 10 0 0 0 0 0 0
ORTHSTE Orthotrichum stellatum Brid. 1 1 0.20 ± 0.00 0 100.0 0 0 0 0
Polytrichales
Polytrichaceae
ATRICRI Atrichum crispum (James) Sull. 7 14 0.19 ± 0.21 0 2.4 4.9 0 0 92.7
ATRIOER Atrichum oerstedianum (Mull. Hal.) Mitt. 12 30 0.68 ± 0.35 0 0 16.2 0 0 83.8
POLYPAL Polytrichum pallidisetum Funck 41 226 2.49 ± 1.17 0.8 6.9 1.7 1.4 0 89.1
450 Southeastern Naturalist Vol. 9, No. 3
% Cover on plot Substrate utilization: when present,
Frequency when present % of cover found on each substrate
# # (mean CWD CWD Live
Phylum/Order/Family Species code Species Plots Seg ± 95% CI) -hard -soft Litter wood Rock Soil
Sphagnales
Sphagnaceae
SPHACAP Sphagnum capillifolium (Ehrh.) Hedw. 1 5 0.86 ± 0.00 0 0 0 0 0 100.0
SPHAGIR Sphagnum girgensohnii Russow 4 34 8.40 ± 12.07 0 0 0 0 0 100.0
SPHAQUI Sphagnum quinquefarium (Lindb. ex Braithw.) 1 5 1.50 ± 0.00 0 0 0 0 0 100.0
Warnst.
SPHAGsp Sphagnum sp. L. 1 3 0.70 ± 0.00 0 0 0 0 0 100.0
SPHASQU Sphagnum squarrosum Crome 1 2 0.16 ± 0.00 0 0 0 0 0 100.0
Tetraphidales
Tetraphidaceae
TETRPEL Tetraphis pellucida Hedw. 54 280 0.86 ± 0.18 9.3 54.8 22.9 4.0 2.9 6.1
Hepatophyta
Jungermanniales
Calypogeiaceae
CALYMUE Calypogeia muelleriana (Schiffn.) Müll. Frib. 11 20 0.46 ± 0.35 1.9 4.5 56.1 1.9 7.1 28.4
CALYNEE Calypogeia neesiana (C. Massal. & Carestia) 1 1 0.030± 0.00 0 100.0 0 0 0 0
Müll. Frib.
CEPHBIC Cephalozia bicuspidata (L.) Dum. 4 5 0.18 ± 0.12 0 31.8 59.1 0 0 9.1
CEPHLUN Cephalozia lunulifolia (Dum.) Dum. 16 33 0.29 ± 0.14 13.0 41.8 30.5 4.0 5.7 5.0
CEPHAsp Cephalozia sp. (Dum. emend. Schiffn.) Dum. 9 17 0.25 ± 0.12 0 75.0 16.2 0 4.0 4.4
NOWECUR Nowellia curvifolia (Dicks.) Mitt. 45 196 1.12 ± 0.29 35.4 63.7 0.6 0 0.3 0.1
Cephaloziellaceae
CEPHRUB Cephaloziella rubella (Nees) Warnst. 1 2 0.13 ± 0.00 0 0 100 0 0 0
Geocalycaceae
CHILPOL Chiloscyphus polyanthos (L.) Corda 1 1 0.16 ± 0.00 0 0 0 0 0 100.0
LOPHHET Lophocolea heterophylla (= Chiloscyphus 2 2 0.05 ± 0.02 0 0 100.0 0 0 0
profundus) (Schrad.) Dumort.
Herbertaceae
HERBADU Herbertus aduncus (Dicks.) A. Gray 2 2 0.08 ± 0.02 0 0 40.0 0 60.0 0
2010 S.E. Stehn, C.R. Webster, J.M. Glime, and M.A. Jenkins 451
% Cover on plot Substrate utilization: when present,
Frequency when present % of cover found on each substrate
# # (mean CWD CWD Live
Phylum/Order/Family Species code Species Plots Seg ± 95% CI) -hard -soft Litter wood Rock Soil
Jubulaceae
FRULTAM Frullania tamarisci (Linnaeus) Dum. Dum. 9 12 0.21 ± 0.12 80.7 7.0 1.8 10.5 0 0
Jungermanniaceae
ANASHEL Anastrophyllum hellerianum (Nees) R.M. Schust. 2 5 0.18 ± 0.02 45.5 45.5 9.1 0 0 0
ANASMIC Anastrophyllum michauxii (F. Weber) H. Buch ex 7 21 0.73 ± 0.76 37.0 45.5 0 0 0 17.5
A. Evans
ANASSAX Anastrophyllum saxicola (Schrad.) R.M. Schust. 1 2 0.60 ± 0.00 0 0 0 0 100.0 0
JAMEAUT Jamesoniella autumnalis (DC.) Steph. 10 24 0.35 ± 0.16 23.6 43.4 17.9 7.5 1.9 5.7
LOPHINC Lophozia incisa (Schrad.) Dum. 4 5 0.11 ± 0.08 14.3 85.7 0 0 0 0
LOPHOsp Lophozia sp. (Dum.) Dum. 2 2 0.08 ± 0.10 0 100.0 0 0 0 0
TRITEXS Tritomaria exsecta (Schrad.) Loeske 4 6 0.35 ± 0.45 0 81.0 7.1 11.9 0 0
Lejeuneaceae
LEJELAM Lejeunea lamacerina (Steph.) Schiffn. 2 3 0.08 ± 0.10 0 0 20.0 0 80.0 0
Lepidoziaceae
BAZZDEN Bazzania denudata (Torr. ex Gottsche. & Lindenb. 4 6 0.22 ± 0.16 0 0 37.0 48.0 14.8 0
& Nees) Trevis
BAZZNUD Bazzania nudicaulis A. Evans 2 3 0.31 ± 0.10 42.1 15.8 0 0 42.1 0
BAZTRIC Bazzania tricrenata (Wahlenb.) Lindb. 2 2 0.20 ± 0.27 0 0 0 0 100.0 0
BAZTRIL Bazzania trilobata (L.) A. Gray 49 333 2.99 ± 1.64 4.2 13.2 74.2 1.3 0.1 7
LEPIREP Lepidozia reptans (L.) Dum. 36 120 0.55 ± 0.27 7.7 28.5 48.5 5.4 1.9 8.1
Pseudolepicoleaceae
BLEPTRI Blepharostoma trichophyllum (L.) Dum. 11 24 0.29 ± 0.18 11.2 20.4 23.5 25.5 13.3 6.1
Radulaceae
RADUTEN Radula tenax Lindb. 1 1 0.10 ± 0.00 0 0 0 0 100.0 0
Scapaniaceae
SCAPNEM Scapania nemorea (L.) Dum. 11 30 0.54 ± 0.23 5.6 7.3 8.4 0 62.6 16.2
SCAPUND Scapania undulata (L.) Dum. 1 1 0.23 ± 0.00 0 0 0 0 0 100.0
Metzgeriales
Aneuraceae
RICCJUG Riccardia jugata R.M. Schust. 1 1 0.23 ± 0.00 0 100.0 0 0 0 0
452 Southeastern Naturalist Vol. 9, No. 3
% Cover on plot Substrate utilization: when present,
Frequency when present % of cover found on each substrate
# # (mean CWD CWD Live
Phylum/Order/Family Species code Species Plots Seg ± 95% CI) -hard -soft Litter wood Rock Soil
RICCPAL Riccardia palmata (Hedw.) Carruth. 2 2 0.05 ± 0.02 0 66.7 33.3 0 0 0
Metzgeriaceae
METZCRA Metzgeria crassipilis (Lindb.) A. Evans 1 1 0.06 ± 0.00 100.0 0 0 0 0 0
METZFUR Metzgeria furcata (L.) Dum. 1 1 0.13 ± 0.00 0 0 0 0 100.0 0
Pallaviciniaceae
PALLLYE Pallavicinia lyellii (Hook.) Carruth. 1 1 0.10 ± 0.00 0 0 100.0 0 0 0