Oklahoma's Native Vegetation Types

1. E-
Oklahoma's Native
Vegetation Types
Bottomland Type Pinon-Juniper
(Flood Plain) Mesa Type
Cypress Bottom Postoak-Blackjack
Forest Type Forest Type
Distribution of Sandsage
Pinus edulis Grassland Type
Loblolly Pine Shinnery Oak
Forest Type Forest Type
Mesquite Shortgrass
Grasslands Highplains Type
Mixedgrass Eroded Stabilized
Plains Type Dune Type
Oak-Hickory Tallgrass
Forest Type Prairie Type
Oak-Pine
Forest Type
10 20 30 40 50 Miles
10 20 40 60 80 Kilometers
Natural Resource Ecology and Management
Oklahoma Cooperative Extension Service
Oklahoma State University

2. Oklahoma's Native
Vegetative Types
Ronald J. Tyrl
Professor of Botany
Department of Botany, Oklahoma State University
Terrence G. Bidwell
Professor and Extension Rangeland Specialist
Department of Natural Resources Ecology and Management
Oklahoma State University
Ronald E. Masters
Director of Research
Tall Timbers Research Station, Tallahassee, Florida
R. Dwayne Elmore
Assistant Professor and Extension Wildlife Specialist
Department of Natural Resources Ecology and Management
Oklahoma State University
John R. Weir
Research Associate
Department of Natural Resources Ecology and Management
Oklahoma State University

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Issued in furtherance of Cooperative Extension work, acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, Robert E. Whitson, Director of Cooperative Extension Service,
Oklahoma State University, Stillwater, Oklahoma. This publication is printed and issued by Oklahoma State University as authorized by the Vice President, Dean, and Director of the Division of Agricultural
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4. ECOGEOGRAPHY
OF OKLAHOMA
B otanically, Oklahoma is a remarkable
state! Within its borders, 173 fami-
lies, 850 genera, and 2,465 species of vascular
The distribution of Oklahoma’s vegetation
types generally reflects these two gradients, with
deciduous forests in the eastern third of the state
plants can be found. Located at the juncture of giving way to tallgrass and mixedgrass prairie in
several physiographic provinces, it is an eco- the middle and shortgrass prairie in the west.
logical crossroad. Plants representative of sev- Temperature in Oklahoma also exhibits sea­
eral phytogeographic regions are present, with sonal and geographical variation, although not
species characteristic of the eastern deciduous as strikingly as precipitation. In the eastern part
forests and grasslands being most common. The of the state, temperature averages are lower in
diversity of plant vegetation types present—14 the summer and higher in the winter. The frost-
are traditionally recognized (Duck and Fletcher free season averages 225 days in the south to
map on the cover)—reflects this diversity of less than 170 days in the north (Figure 1c). As is
species. characteris­tic of a continental climate and famil-
This tremendous diversity of plant spe­cies iar to all who live in the state, daily temperature
and communities in Oklahoma reflects the con- fluctuations can be abrupt and dramatic. As
siderable variation in the state’s climatic, phys- might be expected, species richness—the number
iographic, geological, and edaphic features. A
of different species present in an area—is greatest
plethora of different habitats for plants is present.
in the southeast corner of the state, which has
Brief descriptions of this variation are presented
the mildest winter temperatures and the longest
in the following paragraphs.
growing season.
Climate
Oklahoma’s continental climate is character­ Physiography and Geology
ized by geographical and seasonal variability in In addition to being botanically diverse, Okla­
both precipitation and temperature (Oklahoma homa also is physiographically and geologically
Climatological Survey, 1990). The eastern part of varied and complex (Johnson et al., 1979). Strata
the state is more strongly influenced by moisture from every geological time period can be found
from the Gulf of Mexico than the drier western exposed at one point or another within the state’s
portion of the state. Average yearly precipitation boundaries (Figure 2). Approximately 99% of the
varies from more than 56 inches (1,400 mm) in formations are sedimentary; e.g., the familiar
the southeast to less than 16 inches (400 mm) in Permian sandstones in the west, the Mississip-
the extreme northwest—a gradient of about 1 pian limestones in the northeast, and the Ordo-
inch (25 mm) of rainfall for every 15 miles (25 vician to Pennsylvanian sandstones and shales
km) traveled from east to west (Figure 1a). in the southeast. The remaining 1% is igneous
Likewise, the Precipitation Effectiveness In­ (Wichita Mountains) or slightly metamorphic
dex—the ratio of precipitation to evaporation in (parts of the Ouachita Mountains).
24 hours and an index of the growing conditions One of the common misconceptions about
faced by plants—exhibits a gradient across the Oklahoma is that it is monotonously flat, with little
state; more than 65% in the east to less than 25% topographic variation in its landscape. In reality,
in the west (Figure 1b). this is not the case. Only a few areas of the state are

5. truly flat. Rolling hills and broad plains dissected tisols dominate in the eastern third of the state;
by broad river valleys are more characteristic. The alfisols and mollisols in the center, and inceptisols
Ozark Plateau and three mountain provinces— in the western third. Covering more area of the
Ouachita, Arbuckle, and Wichita—provide con- state than any of the other soil types, the dark,
spicuous relief. In addition, escarpments, cuestas, rich mollisols also are characteristic of the state’s
buttes, mesas, narrow canyons, and deep ravines northeastern prairie and central Panhandle areas.
are present. Twenty-six geomorphic provinces— Also present are vertisols and entisols.
large regions of similar landforms resulting from A mosaic of clay, loam, and sandy soils occurs
ero­sion and/or deposition of sediments—have across the state’s landscape. The physical prop­
been described in Oklahoma (Figure 3). The varied erties of these soils; for example depth, water,
topographic features of these provinces provide a nutri­ent holding capacity, aeration, and resis-
diversity of habitats for plants. tance to erosion, markedly influence the plants
growing in them, and often distinctive, easily
Soils observed assemblages of species will character-
As might be expected because of Oklahoma’s ize them. Illustrative of this relationship is the
geological and physiographical diversity, its soils sandsage-grassland community associated with
also are quite diverse (Figure 4). In general, ul­ the sandy soils of western Oklahoma.
Figure 1. Climatic features of Oklahoma. (a) average annual precipitation (inches; Oklahoma Climatological Survey,
1997).

6. Figure 1. (continued) (b-top) normal precipitation effectiveness (%; adapted from Curry, 1970). (c-bottom) length of grow-
ing season (days; Oklahoma Climatological Survey, 1997).

7. Figure 2. Generalized geologic map of Oklahoma (adapted from Branson and Johnson, 1972).

8. Figure 3. Geomorphic provinces of Oklahoma (adapted from Curtis and Ham, 1972).

9. Figure 4. General Soil Map of Oklahoma (Carter, 1996).

10. VEGETATION
OF OKLAHOMA
correlated with prior studies of vegetation,
O klahoma has 173 families, 850 genera, and
2,465 species of vascular plants. Within its
borders, Oklaho­ma has plants characteristic of
geology, soils, climate, and land use in relation to
game animal populations. In the decades since
the publication of Duck and Fletcher’s map,
the forests of New England, the swamps of the vegetation studies in the state focused only on
Gulf Coast states, the deserts of the Southwest, distinctive, local ecological areas or tracts of par-
the mountains of the West, and the prairies of ticular economic or conservation interest. A mod-
Canada. Fourteen vegetation types are tradition- ern classification of the state’s vegetation was not
ally recognized and they reflect this diversity. attempted until the late 1990s when Hoagland
These vegetation types and their alteration by (2000) published a scheme based on guidelines
human activity are described in the following developed by the Vegetation Subcommittee for
paragraphs. Classification and Information Standards (FGDC,
1997). He rec­ognized 121 alliances in 151 associa-
History of Classification tions. This detailed classification, incorporating
Descriptions of the flora and vegetation of all previous systems, provides scientists with a
Oklahoma begin with the observations of early basis for land­scape mapping and conservation
visitors such as Vasquez de Coronado, Juan de planning.
Onate, Thomas Nuttall, Edwin James with the
Long expedition, Washington Irving, Charles Synopsis of Vegetation Types
Lathrobe, Josiah Gregg, S.W. Woodhouse with In this publication, we continue to use the
the Sitgreaves and Woodruff expedition, G.G. Duck and Fletcher system because it is easy to use
Shumard with the Marcy expedition, and J.M. by indi­viduals with diverse backgrounds. Brief
Bigelow with the Whipple expedition (Bruner, descrip­tions of the 14 categories recognized by
1931; Featherly, 1943). In their journals and expe- them are presented in the following paragraphs.
dition reports are glimpses of the state’s vegeta- It must be noted that although Duck and Fletcher
tion prior to the arrival of eastern tribes of Native mapped the distribution of pinion pine, Pinus
Americans and Europeans. edulis (light blue on map), they did not describe it
Systematic description of the vegetation, how­ as a distinct type in their 1945 treatise, but rather
ever, is traditionally considered to begin with the included it in their Pinon-Juniper Mesa type.
work of W.E. Bruner (1931) and W.F. Blair and
T.H. Hubbell (1938). Their seminal monographs Forest Types
were followed by publication of L.G. Duck and Oak-Hickory
J.B. Fletcher’s vegetation map (1943, 1945), which In Oklahoma, this type represents the western
serves as the cover graphic of this publication. edge of the eastern deciduous forest, with spe-
The most widely recognized of all Oklahoma cies characteristic of the Ozark Plateau and espe­
classific­ations, it comprises 14 vegetation types cially the northeast quarter of the continent. Its
called “game types” because the authors’ intent distribution coincides primarily with the limits
was to describe habitats of game and fur-bearing of the Ozark Plateau Physiographic Province.
animals in the state. The classification, descrip- Taxa typically encountered include: black oak,
tions, and map are the product of field mapping

11. Quercus velutina; white oak, Q. alba; northern red bald cypress, Taxodium distichum; sweetgum, L.
oak, Q. rubra; post oak, Q. stellata; mockernut styraciflua; blackgum, N. sylvatica; water oak, Q.
hickory, Carya tomentosa; and bitternut hickory, C. nigra; willow oak, Q. phellos; and other woody
cordiformis. Pockets of shortleaf pine, P. echinata, and herbaceous species characteristic of the
also are present. Numerous other tree, shrub, and southeast quarter of the continent.
herbaceous species characteristic of the decidu­
ous forest likewise occur. Bottomland (Flood Plain)
Associated with gravel and sand bars, and the
Oak-Pine lowest terrace of all river and creek systems, this
This type is similar to the Oak-Hickory for­est, type occurs across the state and is quite variable
but includes short leaf pine, P. echinata, in abun- with respect to the species present. In the west,
dance and other species characteristic of the south- cottonwood, Populus deltoides; species of willow,
east quarter of the continent. Some ecologists do Salix; and the introduced salt cedar, Tamarix chi-
not recognize it as a distinct type. Its distribution nensis, are encountered. In the east, sycamore,
coincides with the limits of the Ouachita Mountain Platanus oc­cidentalis; green ash, Fraxinus pennsyl-
Province. In addition to the species characterizing vanica; white ash, F. americana; American elm, U.
the Oak-Hickory Forest, also encountered are americana; and species of hackberry, Celtis spp.,
blackjack oak, Q. marilandica; winged elm, Ulmus also occur. Herbs, vines, and shrubs are typically
alata; water oak, Q. nigra; willow oak, Q. phellos; abundant in the understory.
and blackgum, Nyssa sylvatica.
Grassland Types
Post Oak-Blackjack Oak Tallgrass Prairie
As its name implies, this type is dominated Covering the greatest area of Oklahoma, this
by post oak, Q. stellata, and blackjack oak, Q. type dominates the center of Oklahoma from north
marilandica, the two most abundant tree species
to south. In some areas, the Post Oak-Blackjack
in Oklahoma. Distributed in a north-south swath
Oak Type bisects the Tallgrass Prairie and typically
across the state, it typi­cally forms a mosaic with
forms the mosaic collectively referred to as the
the Tallgrass Prairie, the two types being col-
“Cross Timbers.” Often reaching heights of 3.28
lectively referred to as the “Cross Timbers.” As-
sociated species include black hickory, C. texana; to 9.84 feet (1 to 3 m), big bluestem, An­dropogon
Shumard’s oak, Q. shumardii; chittamwood, gerardii; little bluestem, Schizachyrium scoparium;
Bumelia lanuginosa; sugarberry, Celtis lae­vigata; Indiangrass, Sorghastrum nutans; and switchgrass,
and northern hackberry, C. occidentalis. In several Panicum virgatum, dominate. Numerous other
areas along its eastern edge, it is contiguous with perennial grasses and forbs are present.
the oak-hickory and oak-pine forests.
Shortgrass Prairie – High Plains
Loblolly Pine Occurring in the counties of the Panhandle
Also a portion of the eastern deciduous for­ and the extreme northwest corner of the body of
ests, this type is dominated by lob­lolly pine, the state, this type is dominated by shortgrasses
P. taeda, and other species characteristic of the such as buffalograss, Buchloe dactyloides, and blue
southeast quarter of the continent; e.g., southern grama, Bouteloua gracilis. In moister sites, sideoats
red oak, Q. falcata, and sweetgum, Liquidambar grama, Bouteloua curtipendula, and little bluestem,
styraciflua. Its distribution corresponds to the S. scoparium, are present. Characterized by low, ir­
level, sandy soils of the Dissected Coastal Plain regular precipitation, these grasslands are nearly
Geomorphic Province. devoid of trees.
Cypress Bottoms Mixedgrass – Eroded Plains
Present only in the drainages of the Little and Distributed across the western quarter of the
Mountain Fork rivers, this type is dominated by body of the state, this type comprises a mixture

12. of tall- and shortgrasses. The more mesic eastern Oklahoma. As its name implies, stabilized sand
tallgrasses occur where conditions are moist, dunes are its predominant topographic feature.
whereas the western shortgrasses occur in the Sand-loving species playing important roles
drier habitats. Trees and shrubs, such as eastern in stabilization and succession include: giant
redcedar, Juniperus vir­giniana, and hackberry, sandreed, Calamovilfa gigantea; sand bluestem,
Celtis spp., occur in deeply eroded ravines and A. gerardii ssp. hallii; lemon sumac, R. aromatica;
canyons. sand plum, P. angustifolia; soapberry, Sapindus
drummondii; and chittam­wood, B. lanuginosa.
Shrub – Grassland Types
Sandsage Grassland Pinon-Juniper Mesa
This type is defined to encompass all sandy In extreme northwest Cimarron County, Black
grasslands in which sandsage, Artemisia filifolia, Mesa and the surrounding area support isolated
stands of species characteristic of the western half
is an important part of the cover. Distributed
of the continent, including pinon pine, P. edulis;
primarily throughout the northwest corner of
one-seeded juniper, J. monosperma; and ponderosa
the state, including the Panhandle, it occurs
pine, P. ponderosa. Associated with these woody
mainly on the north sides of the principal rivers
species are shortgrass and herbaceous species
and creeks. Species characteristic of sandy soils
typical of the xeric conditions present.
domi­nate and include sand bluestem, A. gerardii
ssp. hallii; sand plum, Prunus angustifolia; lemon Vegetation Types and Ecogeography
sumac, Rhus aromatica; sand lovegrass, Eragrostis As one traverses Oklahoma, it quickly be­
trichodes; and plains yucca, Yucca glauca. comes obvious that the distribution of the state’s
vegetation types is correlated with climatic and
Mesquite Grassland edaphic gradients, and their geographi­cal dis-
Occurring in the southwest corner of the tribution is somewhat predictable. This general
state, this type comprises shortgrass species relationship is summarized in Figure 5. Histori-
such as buffalograss, B. dactyloides; blue grama, cally, overlaying this interaction of soil, precipi-
B. gracilis; and sideoats grama, B. curtipendula, as- tation, and vegetation were frequent wildfires,
sociated with scattered trees of mesquite, Prosopis herbivory, and droughts. However, the distri-
glandulosa. The soils for the most part are clays, butions of some woody species, most notably
with gypsum often present. Redberry juniper, J. eastern red cedar, J. virginiana, and mesquite, P.
pinchotii; plains yucca, Y. glauca; and plains prick- glandulosa, do not exhibit this relationship.
lypear, Opuntia macrorhiza, also are present.
Alteration by Humans
Shinnery Oak – Grassland Although we have summarized the putative
Distributed in sandy soils of the western most “natural” vegetation types of Oklahoma as de­
counties of the body of the state, this type is the scribed by Duck and Fletcher, it must be stressed
eastern edge of a vegetation type that occurs in that these types have been altered significantly by
the Texas Panhandle and eastern New Mexico. human activity. The arrival of prehistoric Native
The dominant shrub is shinnery oak, Q. havardii, Americans, the relocation of Native American
which forms extensive thickets of plants 1.64 to tribes from elsewhere in the country beginning
3.28 feet (0.5 to 1 m) tall interspersed with islands in the 1830s, and the subsequent influx of Euro­
of taller trees called mottes. Associated species pean settlers in vast numbers in the late 1800s
are those character­istic of sandy soils and the impacted Oklahoma’s vegetation. Today, almost
Sandsage Grassland type. all vegetation types have been altered to vary­
ing degrees. Factors contributing to this change
Stabilized Dune include suppression of wildfires, plowing of the
This type occurs on the north sides of the Ci­ land, poor management of grazing by domes­
marron and North Canadian rivers in northwest ticated animals, introduction of invasive exotic
plant species, and urbanization.

13. 10
Climate
Semiarid Humid
TexturedTextured
Coarse Fine
shrubland upland forest forest
S
shortgrass mixed-grass tallgrass
oils
prairie prairie prairie
Figure 5. Distribution of vegetation types in relation to climate and soils, excluding bottomland
forest.
Illustrative of this alteration in the landscape periods of time, and then did not occur for five
of Oklahoma is the change in the oak-hickory and to twelve years. Such a fire regime reflects the
oak-pine forests of the eastern third of the state. occurrence of the early Native American tribes in
The arrival of aboriginal peoples in Okla­homa the areas and weather patterns (Foti and Glenn,
coincided with glacial retreat in North America. 1991; Masters et al., 1995). Subsequent decline in
At that time the eastern portion of the state fire frequency has been correlated with a decline
was dominated by boreal forest as indicated by in the population of Native Americans inhabiting
analyses of pollen cores (Delcourt and Del­court, the area, possibly due to the introduction of dis­
1987 and 1991). As this boreal forest retreated ease by Europeans and conflicts among different
northward, prehistoric peoples used fire as a tool tribes (Gibson, 1965; Wyckoff and Fisher, 1985).
to manipulate the forest (Buckner, 1989; Foti and Following relocation of the Choctaw Nation in
Glenn, 1991). Plant communities developed under southeastern Oklahoma, fire frequency again
the influence of frequent fire coupled with the increased. The region’s fire regime was further
ongoing changes in climatic conditions asso­ciated altered as Europeans began to settle and actively
with the glacial retreat. When Hernando de Soto suppress wildfires (Masters et al., 1995).
journeyed into the Ozark region of Arkansas and Likewise, changes in the appearance of the post
Missouri in the 1500s, his chronicler described a oak-blackjack oak forests of the Oklahoma Cross
land dominated by prairies with trees restricted Timbers are due to the suppression of fire coupled
to the drainages (Beilmann and Brenner, 1951). with poor grazing management (Fran­caviglia,
In the 1700s and 1800s, explorers visiting the 2000). The original character of the Cross Timbers
Ouachita Mountains described the landscape as was probably a mosaic of grasslands, savanna-like
comprising forests or scattered trees interspersed grasslands, oak mottes, oak thickets, and dense
with prairies (Lewis, 1924; Nuttall, 1980). oak woods. Grimm (1984) called this spatial
Today, closed-canopy forests cover both variation a “fire probabil­ity pattern.” It resulted
regions. In contrast to the savannah or open from hot, frequent fires sweeping a landscape that
woodland structure of the past, these forests have contained both fire-prone topographic sites and
overlapping crowns that prevent the growth of natural barriers to fire. Exclusion of fire allowed
shade-intolerant herbaceous and woody plants in the development of closed tree canopies, reduced
the understory. Suppression of fire is the reason the likelihood of fuel accumulations necessary to
for this change. Historically, frequent anthropo­ support intense burns, and permitted invasion of
genic- and (to a lesser extent) lightning-caused woody species such as eastern redcedar into the
fires maintained the open nature of the vegeta­tion grasslands, shrublands, and forests.
(Masters et al., 1995). Although with an average Ranching practices, in particular poor graz­ing
frequency of three to four years, these fires more management and fire suppression, also have had
likely occurred at one- or two-year intervals for a profound impact on the vegetation of Oklaho-

14. 11
ma. Histori­cally, large herbivores such as bison, be destroyed by plowing or urbanization. Thus,
elk, mule deer, white-tailed deer, pronghorn an- restoration efforts can be accomplished on many
telope, and small grazing/browsing mammals sites where native plant communities still exist.
were attracted to areas that had been recently Patterns of grazing — varying from continu­
burned and formed a mosiac with unburned sites ous year-round stocking to multiple-paddock
(Truett et al., 2001). These animals rotationally rotations with cross-fencing and many moves
grazed prairies, shrublands, and forests based on during the graz­ing season — also have a pro-
the scale and timing of fires (Engle and Bidwell, found impact on Oklahoma’s vegetation types,
2001). They congregated on the burned sites for especially the biological diversity of each. Differ­
the entire growing season or until the forage was ent grazing systems produce different landscape
gone. They then moved to another burn site, usu- patterns, different plant community composition,
ally the most recently burned. Thus, the historical and different habitat structure. For example,
landscape structure, landscape pattern, and com- uneven grazing patterns under season-long and
position of the plant communities present were year-long continuous grazing create a condition
directly affected by the fire-grazing interaction of shortgrasses and bare ground interspersed
or what we now call patch-burn/patch-graze among lightly grazed bunches of tall grasses.
(Steuter, 1986; Fuhlendorf and Engle, 2001). Research studies indicate that continuous graz-
The arrival in the 1800s of relocated Native ing at light to moderate stocking rates provides
American tribes and European settlers drastically the best indi­vidual animal performance and a
altered these ecological interactions. Fencing, for moderate level of habitat diversity in Oklahoma.
example, prevented natural animal movement Importantly, it also provides the desired habitat
and allowed areas to be stocked with more cattle structure and composition needed for wildlife
than the land could support. Repeated grazing of species such as Northern Bobwhite Quail, Great-
the grasses and forbs that constitute the fine fuels er-prairie Chicken, and Lesser-prairie Chicken.
supporting fire reduced them to levels at which Rotational grazing with cross-fencing has
fire was no longer a driving ecological force on been advocated to enhance animal performance,
the landscape. As a result, woody plants began to pre­vent spot grazing, and improve grazing
increase, the grasses and forbs declined further, distribu­tion. This approach is based on mostly
and the native plant communities present began unsupported claims and folk lore. For example,
to degrade. proponents have suggested that moving cattle
Today, improper grazing by livestock is still controlled by fencing from grazed to ungrazed
a significant problem throughout the state. Two areas mimics the historical grazing patterns of
terms commonly used to denote improper graz- the native, large herbivores such as bison and
ing are overuse and overgrazing. Overuse by elk. This proposition is erroneous and has no
livestock means that the plants are too short (leaf basis in science or historical evidence. As noted
area needed for photosynthesis too reduced) to above, historical observations and contemporary
maintain their vigor and thus persist at the site. research clearly demonstrate that grazing and
As the preferred grazing plants decline or die, browsing animals are attracted to plants with
other plants, usually those less palatable to the the highest forage quality that occur in the most
grazing animals, replace them. A measurable recently burned area. Animals will spend most of
change in the composition of the vegetation at the their time on the burned area until higher quality
site as the result of overuse is defined as overgraz­ forage is available elsewhere.
ing. This change is easily reversed by a change A significant drawback to rotational grazing
in management in a relatively short period of with cross-fencing is that it reduces the structural
time in the wetter central and eastern parts of and compositional diversity of an ecological site,
Oklahoma. In contrast, in the drier western part, and thus re­duces habitat quality for many wildlife
measurable changes may take several years or species. An approach that mimics historical fire
decades to occur. Fortunately, Oklahoma’s native and grazing patterns is the patch-burn/patch-
plant communi­ties are very resilient and can only graze system (Fuhlendorf and Engle, 2001).

15. 12
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intrusion of forests in the Ozarks. Annals of and Oklahoma. Proceedings of a Conference,
the Missouri Botanical Garden 38:261-282. Winrock International, Morrilton, Arkansas.
Blair, W.F. and T.H. Hubbell. 1938. The biotic Delcourt, P.A. and H.R. Delcourt. 1987. Long-
districts of Oklahoma. American Midland term forest dynamics of the temperate zone.
Naturalist 20:425-454. Ecological Studies 63. Springer-Verlag Inc.,
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Resources, Oklahoma State University, Still- Classification and Information Standards.
water, Okla­homa. United States Geological Survey, Reston,
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NOTES

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