Journal of the Oklahoma Native Plant Society, Volume 9, December 2009
Oklahoma Native Plant Record
Volume 9, December 2009
38
Composition and Structure of Bottomland Forest Vegetation at the
Tiak Research Natural Area, McCurtain County, Oklahoma
Bruce W. Hoagland
*
Newell Alan McCarty
Oklahoma Biological Survey and Oklahoma Biological Survey
Department of Geography University of Oklahoma
University of Oklahoma Norman, Oklahoma 73072
Norman, Oklahoma 73072
*
Corresponding author
ABSTRACT
Although southeastern Oklahoma has substantial areas of bottomland forest, few
studies exist of this vegetation type. We analyzed forest community structure at the Tiak
Research Natural Area of the Ouachita National Forest on the Upper Gulf Coastal Plain.
Vegetation data were collected from 24 12m x 8m macroplots. Percent cover data were
recorded for ferns, fern-allies, and herbaceous angiosperms. Tree sapling and shrub
species were recorded in diameter classes, and numbers of stems in estimated height
classes were recorded for midlevel and canopy trees. One hundred fifty-two taxa of
woody and herbaceous plants were encountered. Toxicodendron radicans and
Arundinaria gigantea were the common understory species. Acer rubrum, A. saccharum,
Carpinus caroliniana, Carya alba, C. texana, Cornus florida, Fraxinus americana,
Liquidambar styraciflua, and Nyssa sylvatica were common as mid-level species.
Quercus lyrata and Q. phellos were the most common canopy layer trees.
INTRODUCTION
The constituent tree species of
bottomland forests in Oklahoma varies
from east to west, as does the upland
vegetation. Some tree species can be found
in bottomland forests at most localities
throughout the state, such as Acer negundo,
A. saccharum, Celtis laevigata, Fraxinus
pennsylvanica, and Ulmus americana (Bruner
1931, Blair and Hubbell 1938, Collins et al.
1981). But the most diverse assemblages of
bottomland forest tree species occur in
eastern Oklahoma, which is fostered by
numerous oak species (i.e., Quercus lyrata, Q.
nigra, Q. michauxii, Q. pagoda, Q. palustris, Q.
phellos, and Q. texana). Quercus lyrata, Q.
michauxii, and Q. texana are restricted to the
Upper Gulf Coastal Plain (UGCP)
extension of southeastern Oklahoma (Blair
and Hubbell 1938). Other bottomland tree
Hoagland & McCarty
https://doi.org/10.22488/okstate.17.100068
species limited to this area are Pinus taeda
and Taxodium distichum (Bruner 1931).
Despite the diversity of woody and
understory species in the bottomland forests
of the UGCP in southeastern Oklahoma,
few vegetation studies have focused on this
area. The dominant species in this forest
type are water tolerant Carya and Quercus
species, as well as Acer rubrum, Liquidambar
styraciflua, and Nyssa sylvatica (Bruner 1931;
Brabander, et al. 1985 ). A quantitative
analysis of woody vegetation at the Little
River National Wildlife Refuge (LRNWR),
located in McCurtain County, identified
three major forest types: Quercus phellos,
Carpinus caroliniana, and Taxodium distichum.
Co-dominant trees at the LRNWR included
A. rubrum, Liquidambar styraciflua, and Quercus
alba (Hoagland et al. 1996).
The objective of this study was to
quantify species composition and aspects of
forest community structure at the TRNA of
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Volume 9, December 2009
Hoagland & McCarty
39
the Ouachita National Forest. The data
collected are intended to serve as a baseline
for analysis of temporal change in
bottomland hardwood forests. This research
area occupies 80.9 ha in North Caney Creek,
McCurtain County, Oklahoma (Fig. 1). It
was established in June of 1990 to protect
the bottomland hardwood forest
community and was the first Research
Natural Area representing the Society of
American Foresters (SAF) type 88 willow
oak - water oak - diamondleaf oak cover
type (Devall 1989).
The TRNA is located within the UGCP
physiographic province of southeastern
Oklahoma (Hunt 1974, Curtis et al. 2008).
The region is composed of deep alluvial
deposits underlain by limestones and shales
of the Washita and Kiamichi formations
(Davis 1960). Relief ranges from 100.9 to
102.1 m above sea-level. Soils are composed
of deep alluvial deposits of Guyton silt loam
group, a poorly drained soil type found on
floodplains throughout southeastern
McCurtain County (Reasoner 1974). The
climate is Subtropical Humid (Trewartha
1968) with warm humid summers and a
mean July temperature of 26.9 °C (80
o
F)
and short, mild winters with a mean January
temperature of 4.0 °C (39
o
F). Mean annual
precipitation is 136 cm (53.5 in.; Oklahoma
Climatological Survey 2009).
METHODS
In order to evaluate habitat structure
and establish baseline stand conditions, it is
necessary to collect data listing the species
present, the number of individuals, and area
occupied. These types of data are of use to
ecologists, foresters, and zoologists, as well
as botanists.
Prior to field data collection, the
locations of macroplots were equidistantly
spaced and established on a 1:24,000 scale
topographic map. Macroplots were then
located and established in the field. Plots
were established in April of 1993 and data
collected in late April, mid July, and early
October of the 1993 field season.
Understory Vegetation data were
collected from units referred to as
macroplots, each of which measured 12 m x
8 m with long axis oriented north to south.
Microplots, measuring 1.0 m x 1.0 m, were
placed in each corner of each macroplot. All
species present in the microplot were
recorded and percent cover visually
estimated in 5% increments. The percent
cover of bryophytes, forest litter, open
water, and exposed soil was recorded. Cover
data for ferns, fern-allies, and herbaceous
angiosperms were also recorded.
Data for Tree Saplings and Shrub
species were collected from a subplot within
the macroplot measuring 8.0 m x 6.0
m.(26.25 ft. x 19.69 ft). Woody species were
assigned to the following classes based on
diameter-at-breast-height (DBH): CL1 = 0 -
2.0 cm, CL2 = 2.1- 6.0 cm, and CL3 = 6.1 -
10.0 cm. These data were collected to
characterize shrub composition and
regeneration potential of canopy tree
species.
Data for Mid-level and Canopy
species were collected from the entire
macroplot. The species names of all trees in
the macroplot were recorded and the height
of each estimated and assigned to the mid-
level category, defined as trees and shrubs
3.0 - 15.0m in height; or “canopy”, defined
as trees in excess of 15.1 m in height.
Taxonomy follows that of the USDA Plants
Database (USDA-NRCS 2009). No voucher
specimens were prepared.
RESULTS AND DISCUSSION
One hundred fifty-two taxa of woody
and herbaceous plants were encountered at
the TRNA in the 1993 field season. Thirty-
four were trees or shrubs (22.4%), 12
woody vines (7.9%), and 106 were
herbaceous plants (69.7%). There were 134
(89.3%) perennials, 11 (7.3%) annuals, and 6
(4.0%) biennials. Carex and Quercus were the
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Volume 9, December 2009
Hoagland & McCarty
40
largest genera with 10 and 7 species,
respectively. Galium aparine, Lonicera japonica,
Morus alba, Vicia villosa, and Trifolium dubium
were non-native species present at the
TNRA. The Oklahoma Natural Heritage
Inventory (2009) tracks nine species at the
TRNA as state rare, though globally secure:
Aralia spinosa (G5S1S2), Aristolochia reticulata
(G4S2), Bignonia capreolata (G5S1), Carex
debilis (G5S1), Desmodium pauciflorum (G5S1),
Justicia ovata (G5S?), Quercus texana
(G4G5S1), Triadenum tubulosum (G4S1S2),
and Uvularia sessilifolia (G5S1). No federally
listed threatened or endangered species were
present.
Understory Vegetation
Of the 152 species encountered in the
microplots, 44 (28.9%) were recorded from
all three sample dates, 50 (32.9%) in two
seasons, and 58 (38.2%) in one season only
(Table 1). Of the taxa recorded in one
season, 23 (39.7%) were in spring only,
21(36.2%) in summer, and 14 (24.3%) only
in fall. The highest mean covers were
“litter” (49.2%) and “exposed soil”
(16.20%).
Seven plant taxa scored annual mean
cover values greater than 1.0%: Toxicodendron
radicans (5.33%), Arundinaria gigantea (2.23%),
Vitis vulpina (1.94%), Parthenocissus
quinquefolia (1.75%), Quercus phellos seedlings
(1.63%), Carex sp. (1.20%), and Acer rubrum
(1.15%). A total of 11 Carex species were
identified, with mean cover values ranging
from 0.55% (C. gravida) to 0.01% (C.
laxiflora).
Mean cover values for each sample
period were comparable; spring, 41%;
summer, 38%; fall, 33%. There was greater
variance in the number of species
encountered between sampling periods. The
most species were recorded for the summer
(108), followed closely by the spring (101),
and fall (83). Toxicodendron radicans had the
highest mean cover for all three sampling
periods. In the spring, T. radicans (6.94%),
Parthenocissus quinquefolia (3.5%), and Vitis
vulpina (3.46%) had the largest average
cover. Likewise in the summer, Toxicodendron
radicans (7.58%) had a substantially larger
cover average value than Arundinaria gigantea
(3.82%) and Quercus phellos seedlings
(2.43%). Fewer species were recorded in the
fall. Only in the fall data did other species
outscore T. radicans in average cover: A.
gigantea (2.01%), Carex sp. (1.74%), Q. phellos
(1.65%) and Q. nigra (1.50%) seedling T.
radicans (1.47%), and Chasmanthium latifolium
(1.46%). Nevertheless, litter and bare
ground had the highest percent cover in all
seasons.
Tree Sapling and Shrub
Nineteen woody species and 281 stems
were recorded in the shrub/sapling plots
(Table 2). All 19 species were represented in
CL1, but only 13 in CL2 and 10 in CL3.
Nine species occurred in all three DBH
classes; Acer rubrum, A. saccharum, Carpinus
caroliniana, Carya alba, C. texana, Cornus
florida, Fraxinus americana, Liquidambar
styraciflua, and Nyssa sylvatica. With the
exception of C. texana, these species are
typical of bottomland forest habitats on the
UGCP.
Each of the three species with 20 or
more stems represents one level in the
forest: Rhododendron canescens, shrub; Ostrya
virginiana, mid-level; and Nyssa sylvatica,
canopy. No tree species exceeded 20 stems
in the remaining DBH classes. Liquidambar
styraciflua, a species of second growth
bottomland forests, had the greatest number
of stems in CL2 and Carpinus caroliniana, a
common understory tree of bottomland
forests, in CL3.
Mid-level and Canopy
Twenty-three species and 3,797 stems
were included in the two height categories
(Table 3). Twelve species occurred in both
the mid-level and canopy categories.
Twenty-two species and the majority of
stems (2,087; 55%) were in the mid-level
category. Liquidambar styraciflua had the most
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Volume 9, December 2009
Hoagland & McCarty
41
stems (385; 18.4%). The stem counts for
Acer rubrum (275, 13.2%), C. texana (245,
11.7%), Q. alba (220, 10.5%), and N. sylvatica
(210, 10.1%) were also high, but
substantially less than L. styraciflua.
The canopy category consisted of 12
species and 1,710 (45%) stems. Quercus
texana was the only species in the canopy
category that was not in the mid-level
category. Quercus lyrata (330 stems, 19.3%)
and Q. phellos (315 stems, 18.4%) were the
most abundant species in the canopy layer.
Quercus rubra (265 stems, 15.5%) and
Liquidambar styraciflua (260 stems, 15.2%)
were also common in the canopy of TRNA.
Acer rubrum, represented by 275 stems in the
mid-level, had only 30 stems (1.8%) in the
canopy. Of the most prominent trees in the
mid-level, only Quercus alba had similar
numbers of stems in the canopy (220 vs.
195).
CONCLUSIONS
Fewer woody plant species were found
at the TRNA (27) than the Little River
National Wildlife Refuge (LRNWR; 47;
Hoagland et al. 1996). Furthermore, with
the exception of Asimina triloba and
Rhododendron canescens, all woody species
reported from TRNA were present at the
LRWNR. The disparity in species numbers
is intriguing. Although the LRNWR is larger
than the TRNA, it was sampled with fewer
plots. The greater number of species at
LRNWR might reflect a higher degree of
habitat variability. The TRNA is
predominately inundated to seasonally
inundated habitat, but also includes upland
vegetation, though limited to the southeast
(plots 4, 5, 8, and 9) and northeast corners
of the site (plots 19, 20, 21, and 22; see Fig.
1).
The macroplot approach adopted for
this study was successful for assessing the
predominant plant species present at the
TRNA, and data collected from microplots
for herbaceous species were informative.
However there are shortcomings in the
types of data collected for woody plant
species. Rather than assigning species to
pre-established classes, actual measurement
of tree and shrub DBH and height would
allow for thorough analysis of woody
species composition and forest structure.
Likewise, a detailed inventory of vascular
plants in the TRNA would benefit future
monitoring projects.
LITERATURE CITED
Blair WF and Hubbell TH. 1938. The biotic
districts of Oklahoma. American Midland
Naturalist 20:425-454.
Brabander JJ, Masters RE, and Short RM.
1985. Bottomland hardwoods of eastern
Oklahoma. U. S. Fish Wildlife Service,
Tulsa, OK. 145 pp.
Bruner WE. 1931. The vegetation of
Oklahoma. Ecological Monographs 1:99-
188.
Collins SL, Risser PG, and Rice EL. 1981.
Ordination and classification of mature
bottomland forests in north central
Oklahoma. Bulletin of the Torrey Botanical
Club 108:152-165.
Curtis NM, Ham, WE, and Johnson KS.
2008. Geomorphic provinces of
Oklahoma. In: Johnson, K.S. and K.V.
Luza (eds.). Earth sciences and mineral
resources of Oklahoma. Oklahoma
Geological Survey, Norman, Oklahoma.
Davis, L. 1960. Geology and groundwater
resources of southern McCurtain
County, Oklahoma. Oklahoma Geological
Survey. Bulletin 86.
Devall, MS 1989. Establishment record for the
Tiak Research Natural Area within the
Ouachita National Forest, McCurtain
County, Oklahoma. Southern Forest
Experiment Station, U. S. Forest
Service, New Orleans.
Hoagland BW, Sorrels LR, and Glenn SM.
1996. Woody species composition of
floodplain forests of the Little River,
McCurtain and LeFlore counties,
Oklahoma Native Plant Record
Volume 9, December 2009
Hoagland & McCarty
42
Oklahoma. Proceedings of the Oklahoma
Academy of Science 76:23-26.
Hoagland BW, Buthod A, Callahan-
Crawford P, Elisens E, and Tyrl R.
2009. Oklahoma vascular plants database.
(www.biosurvey.ou.edu) University of
Oklahoma, Norman. (Accessed 1
January 2009).
Hunt, CB. 1974. Natural regions of the United
States and Canada. W.H. Freeman, San
Francisco. 725 p.
Oklahoma Climatological Survey. 2009.
Oklahoma Climatological Data.
(www.ocs.ou.edu) University of
Oklahoma, Norman. (Accessed 1
November 2009).
Oklahoma Natural Heritage Inventory
(ONHI). 2009. Oklahoma Natural
Heritage Inventory working list of rare
Oklahoma plants.
(www.biosurvey.ou.edu/publicat.html)
University of Oklahoma, Norman.
(Accessed 1 November 2009).
Reasoner, RC 1974. Soil survey of McCurtain
County, Oklahoma. United States
Department of Agriculture,
Washington, D.C.
USDA-NRCS. 2008. The plants database.
(www.plants.usda.gov) National Plant
Data Center, Baton Rouge, LA.
Trewartha, GT 1968. An introduction to
climate. McGraw-Hill, New York.
Figure Location of the Tiak Research Natural Area, Ouachita National Forest, McCurtain
County, Oklahoma. Numbers indicate locations of macroplots.
www.biosurvey.ou.edu
www.ocs.ou.edu
http://www.biosurvey.ou.edu/publicat.html
http://www.plants.usda.gov/
43
Table 1 Species composition of microplots at the Tiak Research Natural Area, Ouachita National Forest, McCurtain County, Oklahoma. Columns denoted
represent average cover value for all seasons (MEAN), number of macroplots (n=24) in which a species was encountered (FREQ), and percentage or relative
frequency (RF) of macroplots in which a species occurred. The remaining columns provided the same data for the spring (April), summer (July), and fall (October)
sampling periods.
MEAN
ANNUAL
FREQ RF
MEAN
SPRING
FREQ RF
MEAN
SUMMER
FREQ RF
MEAN
FALL
FREQ RF
Acalypha rhomboidea 0.04 2 8.3
0.02 1 4
0.01 1 4
0.10 1 4
Acer rubrum 1.15 19 79.2
1.42 14 58
1.29 12 50
0.74 14 58
Acer saccharum 0.24 7 29.2
0.04 1 4
0.38 5 21
0.30 6 25
Agrimonia parviflora 0.09 2 8.3
0.23 2 8
0.04 1 4
0.00 0 0
Agrostis hyemalis 0.08 3 12.5
0.00 0 0
0.13 2 8
0.10 3 13
Allium canadense 0.14 5 20.8
0.41 6 25
0.00 0 0
0.00 0 0
Aralia spinosa 0.01 1 0.0
0.00 0 0
0.04 1 4
0.00 0 0
Arisaema dracontium 0.01 2 8.3
0.04 2 8
0.00 0 0
0.00 0 0
Aristida sp. 0.23 1 4.2
0.00 0 0
0.68 2 8
0.00 0 0
Aristolochia reticulata 0.04 2 8.3
0.00 0 0
0.05 1 4
0.06 2 8
Arundinaria gigiantea 2.23 11 45.8
0.84 9 38
3.82 8 33
2.01 10 42
Asimina triloba 0.20 4 16.7
0.17 3 13
0.13 3 13
0.30 4 17
Athyrium filix-femina 0.01 1 4.2
0.04 1 4
0.00 0 0
0.00 0 0
44
MEAN
ANNUAL
FREQ RF
MEAN
SPRING
FREQ RF
MEAN
SUMMER
FREQ RF
MEAN
FALL
FREQ RF
Berchemia scandens 0.56 11 45.8
0.56 8 33
0.54 7 29
0.58 10 42
Betula nigra 0.03 1 4.2
0.00 0 0
0.00 0 0
0.10 1 4
Bignonia capreolata 0.28 5 20.8
0.00 0 0
0.26 3 13
0.59 5 21
Boehmeria cylindrica 0.30 4 16.7
0.00 0 0
0.78 5 21
0.12 4 17
Botrychium virginianum 0.11 5 20.8
0.05 1 4
0.00 0 0
0.27 7 29
Callicarpa americana 0.19 6 25.0
0.04 1 4
0.25 6 25
0.27 7 29
Campsis radicans 0.39 8 33.3
0.00 0 0
0.61 5 21
0.56 8 33
Carex complanata 0.55 15 62.5
1.54 14 58
0.00 0 0
0.10 1 4
Carex debilis 0.36 6 25.0
1.07 1 4
0.00 0 0
0.00 0 0
Carex gravida 0.65 18 75.0
0.81 11 46
0.51 10 42
0.63 12 50
Carex grayi 0.07 1 4.2
0.00 0 0
0.22 1 4
0.00 0 0
Carex intumescens 0.38 11 45.8
0.74 8 33
0.00 0 0
0.40 7 29
Carex laxiflora 0.01 0 0.0
0.00 0 0
0.02 1 4
0.00 0 0
Carex lupulina 0.54 15 62.5
0.10 2 8
1.35 13 54
0.18 2 8
Carex oligocarpa 0.18 9 37.5
0.00 0 0
0.43 8 33
0.10 1 4
45
MEAN
ANNUAL
FREQ RF
MEAN
SPRING
FREQ RF
MEAN
SUMMER
FREQ RF
MEAN
FALL
FREQ RF
Carex sp. 1.20 21 87.5
1.67 1 4
0.19 2 8
1.74 14 58
Carex squarrosa 0.03 3 12.5
0.04 1 4
0.06 2 8
0.00 0 0
Carex tribuloides 0.28 5 20.8
0.00 0 0
0.83 1 4
0.00 0 0
Carpinus caroliniana 0.39 10 41.7
0.42 5 21
0.38 6 25
0.39 4 17
Carya alba 0.05 4 16.7
0.02 1 4
0.13 3 13
0.00 0 0
Carya aquatica 0.05 3 12.5
0.11 2 8
0.04 1 4
0.00 0 0
Carya sp. 0.19 9 37.5
0.15 5 21
0.00 0 0
0.42 10 42
Carya texana 0.26 12 50.0
0.23 3 13
0.45 12 50
0.10 1 4
Cercis canadensis 0.05 1 4.2
0.06 1 4
0.00 0 0
0.10 1 4
Chasmanthium latifolium 0.05 2 8.3
0.00 1 4
0.15 2 8
0.00 0 0
Chasmanthium laxum 0.40 8 33.3
0.05 1 4
1.14 9 38
0.00 0 0
Chasmanthium
sessiliflorum 0.53 10 41.7
0.00 0 0
0.12 2 8
1.46 11 46
Clitoria mariana 0.04 2 8.3
0.00 0 0
0.05 2 8
0.08 2 8
Convolvulus sp. 0.02 1 4.2
0.00 0 0
0.06 2 8
0.00 0 0
Cornus florida 0.15 7 29.2
0.24 6 25
0.21 3 13
0.00 0 0
46
MEAN
ANNUAL
FREQ RF
MEAN
SPRING
FREQ RF
MEAN
SUMMER
FREQ RF
MEAN
FALL
FREQ RF
Crataegus marshallii 0.17 2 8.3
0.26 3 13
0.12 3 13
0.14 3 13
Desmodium nudiflorum 0.07 2 8.3
0.00 0 0
0.10 2 8
0.10 1 4
Desmodium pauciflorum 0.03 1 4.2
0.00 0 0
0.00 0 0
0.10 2 8
Desmodium sp. 0.08 4 16.7
0.00 0 0
0.13 4 17
0.10 1 4
Dichanthelium
acuminatum var.
fasciculatum 0.01 2 8.3
0.00 0 0
0.03 2 8
0.00 0 0
Dichanthelium boscii 0.18 12 50.0
0.03 1 4
0.52 12 50
0.00 0 0
Dioscorea quaternata 0.68 16 66.7
0.95 10 42
0.98 14 58
0.10 1 4
Diospyros virginiana 0.07 3 12.5
0.11 2 8
0.00 0 0
0.08 2 8
Elephantopus
carolinianus 0.12 6 25.0
0.00 0 0
0.23 5 21
0.13 5 21
Elephantopus
tomentosus 0.01 2 8.3
0.00 0 0
0.04 1 4
0.00 0 0
Elymus virginicus 0.02 0 0.0
0.05 1 4
0.00 0 0
0.00 0 0
Euonymus americana 0.16 7 29.2
0.07 2 8
0.27 6 25
0.13 4 17
Fraxinus americana 0.07 3 12.5
0.13 1 4
0.04 1 4
0.05 1 4
Galium aparine 0.07 5 20.8
0.13 2 8
0.08 3 13
0.00 0 0
47
MEAN
ANNUAL
FREQ RF
MEAN
SPRING
FREQ RF
MEAN
SUMMER
FREQ RF
MEAN
FALL
FREQ RF
Galium circaezans 0.08 3 12.5
0.24 4 17
0.00 0 0
0.00 0 0
Galium concinnum 0.14 6 25.0
0.42 6 25
0.00 0 0
0.00 0 0
Geum canadense 0.15 6 25.0
0.26 3 13
0.10 3 13
0.10 2 8
Gillenia stipulata 0.01 1 4.2
0.00 0 0
0.02 1 4
0.00 0 0
Gratiola neglecta 0.03 2 8.3
0.08 2 8
0.00 0 0
0.00 0 0
Hypericum hypericoides 0.17 6 25.0
0.05 1 4
0.15 5 21
0.29 7 29
Hypericum mutilum 0.03 0 0.0
0.00 0 0
0.00 0 0
0.10 0 0
Hypericum punctatum 0.03 1 4.2
0.00 0 0
0.00 0 0
0.10 1 4
Ilex opaca 0.14 4 16.7
0.11 3 13
0.17 3 13
0.14 4 17
Impatiens capensis 0.50 13 54.2
1.49 13 54
0.00 0 0
0.00 0 0
Juncus coriaceus 0.01 1 4.2
0.04 1 4
0.00 0 0
0.00 0 0
Justicia ovata 0.64 5 20.8
1.62 1 4
0.20 4 17
0.09 2 8
Lactuca canadensis 0.02 2 8.3
0.03 2 8
0.04 1 4
0.00 0 0
Lactuca floridana 0.03 3 12.5
0.06 2 8
0.02 1 4
0.00 0 0
Lactuca sp. 0.01 1 4.2
0.00 0 0
0.04 1 4
0.00 0 0
48
MEAN
ANNUAL
FREQ RF
MEAN
SPRING
FREQ RF
MEAN
SUMMER
FREQ RF
MEAN
FALL
FREQ RF
Liquidambar styraciflua 0.43 15 62.5
0.30 9 38
0.42 11 46
0.56 13 54
Lonicera japonica 0.03 2 8.3
0.00 0 0
0.00 0 0
0.08 3 13
Maianthemum
racemosum 0.03 1 4.2
0.06 1 4
0.02 1 4
0.00 0 0
Matelea biflora 0.08 3 12.5
0.23 3 13
0.00 0 0
0.00 0 0
Mitchella repens 0.23 7 29.2
0.11 3 13
0.15 2 8
0.44 6 25
Monarda punctata 0.02 1 4.2
0.00 0 0
0.00 0 0
0.05 1 4
Monarda sp. 0.03 1 4.2
0.00 0 0
0.00 0 0
0.10 1 4
Monarda russeliana 0.01 0 0.0
0.00 0 0
0.04 1 4
0.00 0 0
Morus alba 0.05 2 8.3
0.04 1 4
0.02 1 4
0.10 1 4
Morus rubra 0.03 1 4.2
0.00 0 0
0.00 0 0
0.10 1 4
Muhlenbergia sp. 0.03 2 8.3
0.00 0 0
0.08 2 8
0.00 0 0
Nyssa sylvatica 0.12 6 25.0
0.00 0 0
0.31 5 21
0.05 2 8
Oligoneuron nitidum 0.19 0 0.0
0.09 2 8
0.26 1 4
0.20 2 8
Onoclea sensibilis 0.02 2 8.3
0.04 1 4
0.01 1 4
0.00 0 0
Ostrya virginiana 0.42 8 33.3
0.50 7 29
0.66 5 21
0.10 1 4
49
MEAN
ANNUAL
FREQ RF
MEAN
SPRING
FREQ RF
MEAN
SUMMER
FREQ RF
MEAN
FALL
FREQ RF
Oxalis stricta 0.13 9 37.5
0.40 10 42
0.00 0 0
0.00 0 0
Packera obovata 0.02 2 8.3
0.02 1 4
0.04 1 4
0.00 0 0
Panium anceps 0.25 12 50.0
0.56 10 42
0.00 0 0
0.19 5 21
Parthenocissus
quinquefolia 1.75 16 66.7
3.50 15 63
1.64 12 50
0.10 1 4
Passiflora lutea 0.09 7 29.2
0.00 0 0
0.18 6 25
0.10 2 8
Penstemon digitalis 0.09 1 4.2
0.24 3 13
0.04 1 4
0.00 0 0
Penthorum sedoides 0.02 1 4.2
0.00 0 0
0.05 1 4
0.00 0 0
Poa autumnalis 0.14 9 37.5
0.31 7 29
0.11 2 8
0.00 0 0
Podophyllum peltatum 0.01 1 4.2
0.02 1 4
0.00 0 0
0.00 0 0
Polygonatum biflorum 0.01 1 4.2
0.00 0 0
0.01 1 4
0.00 0 0
Polygonum
hydropiperoides 0.01 1 4.2
0.00 0 0
0.02 1 4
0.00 0 0
Polygonum virginianum 0.17 5 20.8
0.11 2 8
0.18 5 21
0.21 6 25
Prunella vulgaris 0.01 1 4.2
0.00 0 0
0.03 1 4
0.00 0 0
Prunus serotina 0.05 2 8.3
0.06 2 8
0.04 1 4
0.05 2 8
Pycnanthemum
tenufolium 0.04 1 4.2
0.08 2 8
0.04 1 4
0.00 0 0
50
MEAN
ANNUAL
FREQ RF
MEAN
SPRING
FREQ RF
MEAN
SUMMER
FREQ RF
MEAN
FALL
FREQ RF
Quercus alba 0.23 10 41.7
0.20 6 25
0.40 9 38
0.10 2 8
Quercus lyrata 0.05 4 16.7
0.00 0 0
0.10 5 21
0.06 1 4
Quercus nigra 0.92 17 70.8
0.32 7 29
0.95 13 54
1.50 13 54
Quercus phellos 1.63 20 83.3
0.83 18 75
2.43 13 54
1.65 10 42
Quercus rubra 0.02 3 12.5
0.05 3 13
0.01 1 4
0.00 0 0
Quercus sp. 0.33 16 66.7
0.36 11 4
0.00 0 0
0.62 11 46
Quercus velutina 0.11 1 4.2
0.33 1 4
0.00 0 0
0.00 0 0
Ranunculus abortivus 0.03 3 12.5
0.10 3 13
0.00 0 0
0.00 0 0
Rhododendron
canescens 0.24 6 25.0
0.40 6 25
0.20 3 13
0.14 2 8
Rosa sp. 0.05 3 12.5
0.03 1 4
0.05 2 8
0.06 3 13
Rubus trivalis 0.29 9 37.5
0.38 6 25
0.20 2 8
0.30 6 25
Salvia lyrata 0.03 3 12.5
0.06 3 13
0.03 2 8
0.00 0 0
Sanicula canadensis 0.04 4 16.7
0.00 0 0
0.13 5 21
0.00 0 0
Sassifras albidum 0.03 1 4.2
0.07 1 4
0.02 1 4
0.00 0 0
Saururus cernuus 0.33 3 12.5
0.25 2 8
0.47 3 13
0.26 1 4
51
MEAN
ANNUAL
FREQ RF
MEAN
SPRING
FREQ RF
MEAN
SUMMER
FREQ RF
MEAN
FALL
FREQ RF
Scleria oligantha 0.18 8 33.3
0.00 0 0
0.55 9 38
0.00 0 0
Sisyrinchium
angustifolium 0.01 1 4.2
0.03 1 4
0.00 0 0
0.00 0 0
Smilax bona-nox 0.24 14 58.3
0.34 10 42
0.37 9 38
0.00 0 0
Smilax glauca 0.32 16 66.7
0.05 1 4
0.15 3 13
0.76 17 71
Smilax rotundifolia 0.48 18 75.0
0.35 11 46
0.70 15 63
0.39 9 38
Smilax sp. 0.05 4 16.7
0.00 0 0
0.06 3 13
0.10 1 4
Solidago sp. 0.09 2 8.3
0.00 0 0
0.00 5 21
0.28 3 13
Symphyotrichum
cordifolium 0.02 1 4.2
0.00 0 0
0.05 1 4
0.00 0 0
Symphyotrichum
praealtum 0.08 3 12.5
0.05 1 4
0.18 4 17
0.02 1 4
Symphyotrichum pratens 0.01 0 0.0
0.00 0 0
0.04 1 4
0.00 0 0
Symphyotrichum sp. 0.18 4 16.7
0.10 1 4
0.02 1 4
0.41 4 17
Thalictrum thalictroides 0.02 1 4.2
0.03 1 4
0.04 1 4
0.00 0 0
Tilia americana 0.17 4 16.7
0.31 1 4
0.10 3 13
0.50 1 4
Toxicodendron radicans 5.33 21 87.5
6.94 19 79
7.58 18 75
1.47 16 67
Tradescantia ohiensis 0.10 2 8.3
0.23 3 13
0.06 2 8
0.00 0 0
52
MEAN
ANNUAL
FREQ RF
MEAN
SPRING
FREQ RF
MEAN
SUMMER
FREQ RF
MEAN
FALL
FREQ RF
Triadenum tubulosum 0.19 2 8.3
0.00 0 0
0.35 3 13
0.22 2 8
Trifolium dubium 0.03 0 0.0
0.00 0 0
0.00 0 0
0.10 1 4
Ulmus alata 0.03 2 8.3
0.00 0 0
0.00 0 0
0.08 2 8
Ulmus rubra 0.18 10 41.7
0.00 0 0
0.00 0 0
0.54 12 50
Ulmus serotina 0.11 5 20.8
0.10 1 4
0.21 6 25
0.00 0 0
Uvularia sessiliflora 0.01 1 4.2
0.04 1 4
0.00 0 0
0.00 0 0
Vaccinium corymbosum 0.05 2 8.3
0.04 1 4
0.10 1 4
0.00 0 0
Vaccinium stamineum 0.60 3 12.5
0.21 3 13
0.94 3 13
0.65 4 17
Viburnum rufidulum 0.02 1 4.2
0.06 1 4
0.00 0 0
0.00 0 0
Vicia villosa 0.02 2 8.3
0.05 2 8
0.00 1 4
0.00 1 4
Viola bicolor 0.33 13 54.2
0.99 13 54
0.00 0 0
0.00 0 0
Viola pubescens 0.01 1 4.2
0.02 1 4
0.00 0 0
0.00 0 0
Viola sp. 0.05 3 12.5
0.05 1 4
0.11 4 17
0.00 0 0
Vitis aestivalis 0.12 2 8.3
0.03 1 4
0.25 2 8
0.08 1 4
Vitis vulpina 1.94 19 79.2
3.46 13 54
1.02 13 54
1.34 18 75
53
MEAN
ANNUAL
FREQ RF
MEAN
SPRING
FREQ RF
MEAN
SUMMER
FREQ RF
MEAN
FALL
FREQ RF
Woodwardia areolata 0.13 2 8.3
0.00 0 0
0.33 2 8
0.05 1 4
Zizea aurea 0.08 4 16.7
0.23 4 17
0.00 0 0
0.00 0 0
Bryophytes 4.61 8 33.3
3.87 5 21
5.95 8 33
4.01 7 29
Exposed soil 16.29 20 83.3
18.19 18 75
20.02 20 83
10.65 20 83
Organic litter 49.24 19 79.2
18.19 19 79
57.57 22 92
71.98 19 79
Pooled water 1.90 4 16.7
2.53 3 13
0.04 1 4
3.13 1 4
54
Table 2 Tree sapling and shrub species composition at the Tiak Research Natural Area, Ouachita National Forest, McCurtain County, Oklahoma.
Columns denoted number of stems within each DBH class (CL1 = 0-2.0 cm, CL2 = 2.1-6.0 cm, and CL3 = 6.1-10.0 cm), number of macroplots (n=24)
in which a species was encountered (FREQ), and percentage or relative frequency (RF)of macroplots in which a species occurred.
#Stems
CL1
FREQ RF
#Stems
CL2
FREQ RF
#Stems
CL3
FREQ RF
Acer rubrum 15 11 45.8
3 2 8.3
5 4 16.7
Acer saccharum 16 5 20.8
3 1 4.2
2 2 8.3
Asimina triloba 4 1 4.2
0 0 0.0
0 0 0.0
Carpinus caroliniana 19 8 33.3
7 7 29.2
8 7 29.2
Carya alba 11 6 25.0
7 6 25.0
6 5 20.8
Carya aquatica 1 1 4.2
0 0 0.0
0 0 0.0
Carya texana 12 9 37.5
9 6 25.0
2 2 8.3
Cersis canadensis 3 1 4.2
0 0 0.0
0 0 0.0
Cornus florida 6 3 12.5
1 1 4.2
1 1 4.2
Euonymus americana 1 1 4.2
0 0 0.0
0 0 0.0
55
#Stems
CL1
FREQ RF
#Stems
CL2
FREQ RF
#Stems
CL3
FREQ RF
Fraxinus americana 2 2 8.3
2 2 8.3
1 1 4.2
Ilex opaca 8 5 20.8
1 1 4.2
0 0 0.0
Liquidambar styraciflua 7 6 25.0
10 5 20.8
6 5 20.8
Nyssa sylvatica 25 12 50.0
8 5 20.8
5 4 16.7
Ostrya virginiana 21 9 37.5
1 1 4.2
0 0 0.0
Quercus alba 3 3 12.5
0 0 0.0
1 1 4.2
Quercus nigra 1 1 4.2
0 0 0.0
0 0 0.0
Rhododendron canescens 21 4 16.7
1 1 4.2
0 0 0.0
Ulmus alata 7 4 16.7
7 4 16.7
0 0 0.0
Total stems 184
60
37
56
Table 3 Woody species composition within Mid-level and Canopy height classes at the Tiak Research Natural Area, Ouachita National Forest, McCurtain
County, Oklahoma. Mid-level woody plants are defined as trees and shrubs 3-15 m in height and Canopy as trees in excess of 16 m. The first column in each
category represents the number of macroplots (n=24) in which a species was encountered (FREQ), followed by the percentage or relative frequency (RF) of
macroplots in which a species occurred, the total number of stems (#Stems) and mean number of stems (MStems) for a species.
Mid-level
FREQ RF #Stems MStems
Canopy
FREQ RF #Stems MStems
Acer rubrum 10 42 275 11.4
0 0 30 1.2
Acer saccharum 3 13 55 2.3
0 0 0 0.0
Carpinus caroliniana 4 17 100 4.2
0 0 0 0.0
Carya alba 4 17 105 4.4
0 0 0 0.0
Carya aquatica 1 4 35 1.5
1 4 40 1.7
Carya texana 11 46 245 10.2
1 4 25 1.0
Cornus florida 3 13 15 0.6
0 0 0 0.0
Euonymus americana 1 4 20 0.8
0 0 0 0.0
Fraxinus americana 4 25 1.0
0 0 0 0.0
Ilex opaca 2 8 45 1.9
0 0 0 0.0
Mid-level
FREQ RF #Stems MStems
Canopy
FREQ RF #Stems MStems
Liquidambar styraciflua 13 54 385 16.0
9 38 260 10.8
Nyssa sylvatica 10 42 210 8.8
2 8 45 1.9
Ostrya virginiana 2 8 65 2.7
0 0 0 0.0
Quercus alba 8 33 220 9.2
6 25 195 8.1
Quercus lyrata 3 13 65 2.7
7 29 330 13.8
Quercus nigra 1 4 15 0.6
2 8 60 2.5
Quercus texana 0 0 0 0.0
2 8 70 2.9
Quercus phellos 3 13 25 1.0
6 25 315 13.1
Quercus rubra 3 13 70 2.9
8 33 265 11.0
Quercus sp. 1 4 15 0.6
3 13 45 1.9
Rhododendron canescens 2 8 35 1.5
0 0 0 0.0
58
Mid-level
FREQ RF #Stems MStems
Canopy
FREQ RF #Stems MStems
Tilia americana 2 8 17 0.7
0 0 0 0.0
Ulmus serotina 2 8 45 2.7
1 4 30 13.8
Total Stems 2,087
1,710