Prepared in cooperation with the Bureau of Land Management and the Great Plains 

Landscape Conservation Cooperative

Estimated Historical Distribution of Grassland 

Communities of the Southern Great Plains

By Gordon C. Reese, Daniel J. Manier, Natasha B. Carr, Ramana Callan, Ian I. F. Leinwand,

Timothy J. Assal, Lucy Burris, and Drew A. Ignizio

Open-File Report 2016–1184

U.S. Department of the Interior

U.S. Geological Survey
ii

U.S. Department of the Interior

SALLY JEWELL, Secretary

U.S. Geological Survey

Suzette M. Kimball, Director

U.S. Geological Survey, Reston, Virginia: 2016

For more information on the USGS—the Federal source for science about the Earth,

its natural and living resources, natural hazards, and the environment—visit

http://www.usgs.gov/ or call 1–888–ASK–USGS (1–888–275–8747).

For an overview of USGS information products, including maps, imagery, and publications,

visit http://store.usgs.gov/.

Any use of trade, firm, or product names is for descriptive purposes only and does not imply

endorsement by the U.S. Government.

Although this information product, for the most part, is in the public domain, it also may

contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items

must be secured from the copyright owner.

Suggested citation:

Reese, G.C., Manier, D.J., Carr, N.B., Callan, Ramana, Leinwand, I.I.F., Assal, T.J., Burris, Lucy, and 

Ignizio, D.A., 2016, Estimated historical distribution of grassland communities of the Southern Great 

Plains: U.S. Geological Survey Open-File Report 2016–1184, 13 p., 

https://doi.org/10.3133/ofr20161184.

ISSN 2331-1258 (online)
iii

Contents

Scientific Names for Species Mentioned in This Report ................................................................................iv

Acknowledgments.......................................................................................................................................... v

Abstract ......................................................................................................................................................... 1

Purpose and Scope ....................................................................................................................................... 1

Methods......................................................................................................................................................... 4

Products ...................................................................................................................................................... 11

Disclaimers .................................................................................................................................................. 11

Summary ..................................................................................................................................................... 12

References Cited......................................................................................................................................... 12

Figures

1. Map of the Southern Great Plains Rapid Ecoregional Assessment project area .............................. 3

2. Map showing the estimated historical distribution of grassland and adjacent communities in 

the Southern Great Plains Rapid Ecoregional Assessment project area .......................................... 8

Tables

1. Dominant indicator species used to classify grassland communities................................................ 5

2. Attributes for the estimated historical grassland communities dataset.............................................. 6

3. Community types for the estimated historical grasslands dataset and corresponding 

LANDFIRE Biophysical Settings names ........................................................................................... 8

Conversion Factors

U.S. customary units to International System of Units

Multiply By length To obtain

foot (ft) 0.3048 meter (m)

yard (yd) 0.9144 meter (m)

Datum

Vertical coordinate information is referenced to the North American Datum of 1983 (NAD 83).

Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD 83).
iv

Abbreviations

BLM Bureau of Land Management

BpS Biophysical Settings

ESDs Ecological Site Descriptions

ESI Ecological Site Inventory

ESIS Ecological Site Information System

EVT Existing Vegetation Type

GAP Gap Analysis Project

GPLCC Great Plains Landscape Conservation Cooperative

LANDFIRE Landscape Fire and Resource Management Planning Tools

NRCS Natural Resources Conservation Service

REA Rapid Ecoregional Assessment

SSURGO Soil Survey Geographic Database

USGS U.S. Geological Survey

Scientific Names for Species Mentioned in This Report

Common Name

Alkali cordgrass 

Scientific Name

Spartina gracilis

Alkali sacaton Sporobolus airoides

Arizona cottontop Digitaria californica

Arizona fescue Festuca arizonica

Big bluestem Andropogon gerardii

Black grama Bouteloua eriopoda

Blue grama Bouteloua gracilis

Bluebunch wheatgrass Pseudoroegneria spicata spicata

Buffalograss Bouteloua dactyloides

Cane bluestem Bothriochloa barbinodis

Green needlegrass Nassella viridula

Gypsum grama Bouteloua breviseta

Idaho fescue Festuca idahoensis

Indiangrass Sorghastrum nutans

Inland saltgrass Distichlis spicata

Little bluestem Schizachyrium scoparium

Mountain brome Bromus marginatus

Mountain muhly Muhlenbergia montana

Needle and thread Hesperostipa comata

Prairie sandreed Calamovilfa longifolia

Sand bluestem Andropogon hallii

Sand sagebrush Aretemesia filifolia

Sand dropseed Sporobolus cryptandrus

Shinnery oak Quercus havardii

Sideoats grama Bouteloua curtipendula
v

Scientific Names for Species Mentioned in This Report—Continued

Common Name

Silver beardgrass

Scientific Name

Bothriochloa laguroides torreyana

Streambank wheatgrass Elymus lanceolatus lanceolatus

Switchgrass Panicum virgatum

Threadleaf sedge Carex filifolia

Tobosagrass Pleuraphis mutica

Vine mesquite Panicum obtusum

Western wheatgrass Pascopyrum smithii

Acknowledgments

The impetus and oversight for this project were provided by the Southern Great Plains Rapid Ecoregional

Assessment advisors and technical experts including Steve Tryon, David Wood, Melanie Barnes, Janine Book, and 

Laurence Levesque of the Bureau of Land Management, and Nicole Athearn of the Great Plains Landscape 

Conservation Cooperative. We greatly appreciate technical reviews of the general approach or the estimated 

historical grassland map provided by Robert Means and George Soehn of the Bureau of Land Management; Lee 

Elliot, Missouri Resource Assessment Partnership; Rick Schneider, Nebraska Natural Heritage Program; Esteban 

Muldavin, New Mexico Natural Heritage Program; Duane German, Texas Parks and Wildlife Department; Joe 

Stevens, Joanna Lemly, Karin Decker, and Michael Menefee, Colorado Natural Heritage Program; Patrick J. 

Comer, NatureServe; Steven Rolfsmeier, Chadron State College; Russell Martin, Texas Parks and Wildlife; Russ 

Horton, Oklahoma Department of Wildlife Conservation; and Kelly Kindscher, Kansas Biological Survey. Tammy 

Fancher, Patrick Anderson, and Colin Talbert of the U.S. Geological Survey provided reviews of this report, the

data release, and the associated metadata.
1

Estimated Historical Distribution of Grassland

Communities of the Southern Great Plains

By Gordon C. Reese,1 Daniel J. Manier,1 Natasha B. Carr,1 Ramana Callan,2 Ian I. F. Leinwand,2

Timothy J. Assal,1 Lucy Burris,1 and Drew A. Ignizio1

Abstract

The purpose of this project was to map the estimated distribution of grassland communities of 

the Southern Great Plains prior to Euro-American settlement. The Southern Great Plains Rapid 

Ecoregional Assessment (REA), under the direction of the Bureau of Land Management and the Great 

Plains Landscape Conservation Cooperative, includes four ecoregions: the High Plains, Central Great 

Plains, Southwestern Tablelands, and the Nebraska Sand Hills. The REA advisors and stakeholders 

determined that the mapping accuracy of available national land-cover maps was insufficient in many 

areas to adequately address management questions for the REA. Based on the recommendation of the 

REA stakeholders, we estimated the potential historical distribution of 10 grassland communities within 

the Southern Great Plains project area using data on soils, climate, and vegetation from the Natural 

Resources Conservation Service (NRCS) including the Soil Survey Geographic Database (SSURGO) 

and Ecological Site Information System (ESIS). The dominant grassland communities of the Southern 

Great Plains addressed as conservation elements for the REA area are shortgrass, mixed-grass, and sand 

prairies. We also mapped tall-grass, mid-grass, northwest mixed-grass, and cool season bunchgrass 

prairies, saline and foothill grasslands, and semi-desert grassland and steppe. Grassland communities 

were primarily defined using the annual productivity of dominant species in the ESIS data. The

historical grassland community classification was linked to the SSURGO data using vegetation types 

associated with the predominant component of mapped soil units as defined in the ESIS data. We 

augmented NRCS data with Landscape Fire and Resource Management Planning Tools (LANDFIRE)

Biophysical Settings classifications 1) where NRCS data were unavailable and 2) where fifth-level 

watersheds intersected the boundary of the High Plains ecoregion in Wyoming. Spatial data representing 

the estimated historical distribution of grassland communities of the Southern Great Plains are provided 

as a 30 x 30-meter gridded surface (raster dataset). This information will help to address the priority 

management questions for grassland communities for the Southern Great Plains REA and can be used to 

inform other regional-level land management decisions.

Purpose and Scope

The Bureau of Land Management (BLM) is implementing a landscape approach that 

incorporates multiscale information to assess the condition and trends of resources

(http://www.blm.gov/wo/st/en/prog/more/Landscape_Approach.html). A major component of the BLM 

 1

U.S. Geological Survey. 

2

Cherokee Nation Technologies.
2

landscape approach is the Rapid Ecoregional Assessment (REA) program, which provides information 

to facilitate development of broad-scale management strategies across jurisdictional boundaries. The

REAs identify and map priority ecological communities and species for particular ecoregions, determine 

the degree of risk from development and other change agents, and provide assessments of ecological 

conditions including conservation and restoration potential. The purpose of this project was to map the 

estimated distribution of grassland communities of the Southern Great Plains prior to Euro-American 

settlement.

The BLM partnered with the Great Plains Landscape Conservation Cooperative (GPLCC) to 

ensure that the results of the Southern Great Plains REA provide information useful for addressing 

management issues identified by a diverse set of stakeholders representing the REA and GPLCC. The 

Southern Great Plains REA project area includes the full extent of the GPLCC’s area 

(http://www.greatplainslcc.org/about/), as well as the following Omernik Level III ecoregions 

(Omernik, 1987): High Plains, Central Great Plains, Southwestern Tablelands, and the Nebraska Sand 

Hills (and an adjacent buffer delineated by fifth-level watersheds intersecting the ecoregion boundaries)

(fig. 1A). The dominant vegetation communities in these four ecoregions are shortgrass, mixed-grass, 

and sand prairies, which were identified as priority ecological communities by the Southern Great Plains 

REA stakeholders (Assal and others, 2015). A priority management issue for this REA is how 

development (including agricultural, energy, transportation, and urban) has fragmented and reduced 

connectivity of Great Plains ecological communities (Assal and others, 2015). Our objective was to map 

the estimated distribution of grassland communities of the Southern Great Plains prior to EuroAmerican settlement to address management questions for the REA.

Both current and estimated historical land-cover maps were needed to quantify how 

development has altered landscape structure. For previous REAs, regional or national land-cover 

datasets, such as those from the Gap Analysis Program (GAP) and the Landscape Fire and Resource 

Management Planning Tools (LANDFIRE) program were used to map ecological communities (Bryce 

and others, 2012; Carr and Melcher, 2015; Comer and others, 2013). Because of the accuracy 

limitations of existing land-cover datasets and challenges associated with mapping the estimated 

distribution of grasslands prior to land-use conversions, REA stakeholders suggested using the

Ecological Site Information System (ESIS) (National Resources Conservation Service, 2015a) and Soil 

Survey Geographic Database (SSURGO) (National Resources Conservation Service, 2015b) to map the 

estimated historical distribution of native grassland communities across the Southern Great Plains for 

the REA.

We conducted a preliminary review and analysis of the suitability of using existing land-cover 

datasets, including GAP (http://gapanalysis.usgs.gov/) and LANDFIRE (Landscape Fire and Resource 

Management Planning Tools, 2012), to map the priority grassland communities for the REA project 

area. The large size of the project area (spanning eight states) required two GAP regions (northwest and 

southwest); pronounced classification discrepancies along the boundaries precluded the use of the GAP 

data for mapping grasslands for the REA. We evaluated two LANDFIRE datasets for use: Biophysical 

Settings (BpS), representing the potential natural vegetation prior to Euro-American settlement, and 

Existing Vegetation Type (EVT) (Rollins, 2009). 

LANDFIRE was developed to map fuels and typically depicts woody fuels more accurately than 

herbaceous fuels in rangelands because of limited field data in rangelands (Reeves and others, 2009).

For comparison purposes, we used the Texas Ecological Systems Classification vegetation map, 

developed by the Missouri Resource Assessment Program (Elliot, 2010), as our reference map in the

area of overlap between the Texas vegetation map and the REA project area because the finer resolution 

(10 x 10-meter raster dataset) and extensive field data (14,000 survey plots) were assumed to provide a
3

Figure 1. Map of the Southern Great Plains Rapid Ecoregional Assessment project area. A, Omernik Level III

ecoregions and the buffer region, which includes fifth-level watersheds intersected by the ecoregion boundaries 

and covers the full extent of the Great Plains Landscape Conservation Cooperative. B, Spatial coverage of the

primary (National Resources Conservation Service) and supplemental (Landscape Fire and Resource 

Management Planning Tools) data sources used to estimate the historical distribution of grassland and other 

community types.
4

more accurate map than LANDFIRE or NRCS data. Our preliminary analysis indicated that NRCSderived classifications, which combine information from both ESIS and SSURGO, generally had the 

best correspondence with the Texas Ecological Systems Classification, compared to LANDFIRE EVT

and BpS, supporting the REA stakeholders’ recommendation to use NRCS data to map grasslands for 

the Southern Great Plains REA. This approach assumes that the combination of substrate and climate is 

correlated with the composition and productivity of prairie vegetation. Understanding of these relations 

is in accord with common assumptions that underlie the development and use of Ecological Site 

Descriptions (ESDs) and is well established in practice and empirical research (for example, Epstein and 

others, 1998).

Methods

The potential distribution (Zerbe, 1998) of grass-dominated ecological communities in the 

Southern Great Plains was estimated using soil composition, annual precipitation, and vegetation plot 

data developed by the NRCS. SSURGO contains soil information delineated by map units and we used 

the dominant soils component, as represented by the largest percentage, for any map unit with multiple 

soil components to map the distribution of soil types.

Plant communities for each SSURGO map unit were identified using the ESIS

(https://esis.sc.egov.usda.gov). Ecological sites are characterized by soil and physical characteristics,

associated plant communities, vegetation productivity, and the potential for a given community to 

respond similarly to management actions and natural disturbances. The ESIS includes the Ecological 

Site Inventory (ESI) database and ESDs. The ESI provides plot-level survey data on soils and plant 

species productivity for each ecological site. The ESDs are peer reviewed reports that include 

summarized plot-level survey data and synthesize information on physical factors (soils, temperature, 

precipitation, hydrology, geology, physiographic features), biotic features (plant species occurrence, 

plant community composition, plant production), and ecological dynamics (disturbance regimes such as 

grazing, fire, drought). To associate each spatial map unit with the appropriate ecological site, the Soil 

Component and Ecoclass tables in SSURGO were used.

We classified the composition of sites for the project area into 10 grassland community types 

(shortgrass, mixed-grass, sand, tall-grass, mid-grass, northwest mixed-grass, and cool season 

bunchgrass prairies; semi-desert grassland and steppe; and saline and foothill grasslands; table 1). Our 

classification considered the naming conventions established by the National Vegetation Classification 

(Nelson and others, 2015) and used the same terminology when applicable. However, to support 

requests from managers and planners, we developed a classification falling between Group and 

Association levels of the National Vegetation Classification hierarchy similar to types considered in 

habitat conservation and management. Only shortgrass, mixed-grass, and sand prairies are widely 

distributed throughout the four ecoregions in the project area; the remaining seven grassland types 

primarily occur along the periphery of the ecoregions and in the buffer region. Although the less 

common grassland types were not a focus of our classification, they were included for completeness and 

context relative to adjacent areas. 

To classify each ecological site, we used the three dominant species, as indicated by 

aboveground annual productivity (table 1). We followed species naming conventions established by the 

U.S. Department of Agriculture (Natural Resources Conservation Service, 2015c). Field estimates of 

species productivity from ESI vegetation plots within ecological sites without ESDs were averaged by 

species and normalized by calculating the percent of total annual yield in each ecological site. 

Ecological sites with mesic soils or wetland plants were classified as aquatic communities and sites 

dominated by woody species were classified as shrubland, woodland, and forest. LANDFIRE BpS 
5

(Landscape Fire and Resource Management Planning Tools, 2012) was used to classify areas with 

insufficient NRCS data and areas within the Southern Great Plains buffer region (fig. 1B), accounting 

for approximately 4 percent of the project area.

Table 1. Dominant indicator species used to classify ecological sites into grassland communities.

Community type Dominant indicator species

Shortgrass prairie Blue grama, buffalograss, western wheatgrass

Mixed-grass prairie Big bluestem, blue grama, little bluestem, sideoats grama

Sand prairie Prairie sandreed, sand bluestem, sand dropseed, sand sagebrush, shinnery oak

Tall-grass prairie Big bluestem, Indiangrass, little bluestem, switchgrass

Mid-grass prairie Arizona cottontop, cane bluestem, sideoats grama, silver beardgrass, vine mesquite 

Northwest mixed-grass prairie Bluebunch wheatgrass, green needlegrass, Idaho fescue, streambank wheatgrass

Cool season bunchgrass prairie Blue grama, needle and thread, threadleaf sedge, western wheatgrass

Semi-desert grassland and steppe Black grama, gypsum grama, tobosagrass

Saline grassland Alkali cordgrass, alkali sacaton, inland saltgrass

Foothill grassland Arizona fescue, mountain brome, mountain muhly

Initial mapping of grassland communities using SSURGO and the associated ESIS revealed gaps 

and inconsistencies resulting from missing data and inaccurate classification boundaries along county

and state lines. Map units lacking associated ESDs or ESI data were classified using vegetation 

described for nearby ecological sites with similar soil properties. Map units with classification 

inconsistencies along political boundaries (county or state lines) were assigned to the same community 

class as an adjacent ecological site with similar soil properties. In a small portion of the project area, 

nearby sites with similar soil properties were lacking; in these cases, we used LANDFIRE BpS to 

address the data gap (fig. 1B). The source of information used to classify map units is documented in the 

“Dataset source” attribute (table 2).

The estimated historical distribution map delineates 10 grassland communities (fig. 2). To 

provide a complete coverage of other communities in the project area, we also used NRCS and 

LANDFIRE BpS to map the estimated historical distribution of shrublands, woodlands, and forests; 

riparian areas and wetlands; open water; and sparsely vegetated land-cover classes. Because our purpose 

was to classify and map the historical distribution of grasslands, the woody and aquatic communities 

were grouped into general community types. To identify potential wetland and riparian areas, NRCS 

data were used to identify the presence of mesic soils and hydrophilic plant species; identification of 

potential shrublands, savanna, and open woodlands used the presence of indicator grasses and shrubs, 

and tree species (oak, juniper, or pine) with 10 to 25 percent cover. In areas where LANDFIRE BpS was 

used as the data source for classifying woody vegetation, we combined all vegetation types using the 

BpS names corresponding to shrublands, woodlands, and forests (table 3). We reclassified several BpS 

types corresponding to desert scrub types as saline grasslands because those scrub types are uncommon 

within the project area and generally occurred in proximity to areas classified as saline grasslands using 

NRCS data (table 3), supporting the reclassification.

The attribute names in the dataset are listed and defined in table 2 (Callan and others, 2016). The 

attributes include those derived by the U.S. Geological Survey (USGS) and attributes from the 

SSURGO data that were used in determining land-cover classification. The associated metadata 

includes expanded attribute definitions summarized in table 2 (Callan and others, 2016).
6

Table 2. Attributes (names and abbreviations), definitions, and originator of the attribute field for the estimated 

historical distribution of grassland communities dataset. Attribute abbreviations are used in the dataset attribute 

table and defined in the metadata (Callan and others, 2016).

[NRCS, Natural Resources Conservation Service]

Attribute

originator

Attribute

name

Attribute 

abbreviation Definition

U.S. Geological 

Survey

Object Identifier OID Unique identifier for each row in the attribute table

Feature Value Value Grid cells linked by a feature will have identical 

values

Count Count Count of grid cells for the Feature Value

Vegetation Class Class Assigned vegetation community class

Vegetation Class Code ClassCode Numerical representation of the Vegetation Class

Dataset source DataSource Source of the data used to identify and classify the 

Vegetation Class 

Type of information Info_Type Type of information used to classify the Vegetation 

Class

Additional details on 

data used

DataDetail Additional details on the data used to classify the 

Vegetation Class 

Lookup Key LookupKey Ecological Site Description ID, map unit key, or 

NRCS classification used to identify the 

Vegetation Class; this is the spatial unit to which a 

Vegetation Class is assigned

Natural Resources 

Conservation 

Service1

Map Unit Key Mukey Map Unit Key is the unique identifier from the 

NRCS soil component table

Component Key Cokey Component Key is a string of characters used to 

uniquely identify a record from the NRCS 

component table

Component Percentage Comppct_r Percentage of the soil component of the map unit 

from the NRCS component table

Component Name Compname Name assigned to a NRCS soil component based on 

the soil properties

Geomorphic Description Geomdesc A narrative description of the geomorphic setting of 

the soil component 

Taxonomic Class Name Taxclname The taxonomic class from the NRCS component 

table; the name is a concatenation of the soil 

taxonomy subgroup and family for a given soil 

Ecological Classification 

Identifier

Ecoclassid Identifier of a particular ecological community from 

the NRCS coecoclass table

Ecological Classification 

Name

Ecoclassna Descriptive name of a particular ecological 

community from the NRCS coecoclass table

1

Soil Survey Geographic Database (SSURGO).
7

Figure 2. Map showing the estimated historical distribution of grassland and adjacent communities in the 

Southern Great Plains Rapid Ecoregional Assessment project area, which includes the Great Plains Landscape 

Conservation Cooperative area. For illustration, several minor grassland communities are combined and sparsely

vegetated areas are not displayed due to their small size, but are retained in the dataset.
8

Table 3. Community types for the estimated historical distribution of grasslands dataset and corresponding 

LANDFIRE Biophysical Settings names.

[LANDFIRE, Landscape Fire and Resource Management Planning Tools]

Community type Biophysical Settings name LANDFIRE 

Code

Cool season bunchgrass prairie1 Not applicable

Foothill grassland Northern Rocky Mountain Lower Montane–Foothill–Valley Grassland 11390

Northern Rocky Mountain Subalpine–Upper Montane Grassland 11400

Rocky Mountain Subalpine–Montane Mesic Meadow 11450

Southern Rocky Mountain Montane–Subalpine Grassland 11460

Western Great Plains Foothill and Piedmont Grassland 11470

Mixed-grass prairie Central Mixedgrass Prairie 11320

Northwest mixed-grass prairie Northwestern Great Plains Mixedgrass Prairie 11410

Saline grassland2 Chihuahuan Mixed Salt Desert Scrub 10750

Inter-Mountain Basins Mixed Salt Desert Scrub 10810

Inter-Mountain Basins Mixed Salt Desert Scrub—South 10811

Inter-Mountain Basins Mixed Salt Desert Scrub—North 10812

Sand prairie Chihuahuan Stabilized Coppice Dune and Sand Flat Scrub 10760

Western Great Plains Sandhill Steppe 10940

Western Great Plains Sand Prairie 11480

Chihuahuan Sandy Plains Semi-Desert Grassland 11330

Semi-desert grassland and 

steppe

Chihuahuan Grama Grass–Creosote Steppe 11003

Apacherian-Chihuahuan Semi-Desert Grassland and Steppe 11210

Chihuahuan Gypsophilous Grassland and Steppe 11220

Inter-Mountain Basins Semi-Desert Grassland 11350

Chihuahuan Loamy Plains Desert Grassland 15030

Shortgrass Prairie Western Great Plains Shortgrass Prairie 11490

Tall-grass Prairie Western Great Plains Tallgrass Prairie 11500

Central Tallgrass Prairie 14210

Southern Blackland Tallgrass Prairie 14220

Southeastern Great Plains Tallgrass Prairie 14230

Shrubland, woodland, and 

forest

Rocky Mountain Aspen Forest and Woodland 10110

Western Great Plains Dry Bur Oak Forest and Woodland 10130

Colorado Plateau Pinyon-Juniper Woodland 10160

Madrean Encinal 10230

Madrean Lower Montane Pine-Oak Forest and Woodland 10240

Madrean Pinyon-Juniper Woodland 10250

Northwestern Great Plains Highland White Spruce Woodland 10480

Rocky Mountain Foothill Limber Pine-Juniper Woodland 10490

Rocky Mountain Lodgepole Pine Forest 10500
9

Table 3. Community types for the estimated historical distribution of grasslands dataset and corresponding 

LANDFIRE Biophysical Settings names.—Continued

[LANDFIRE, Landscape Fire and Resource Management Planning Tools]

Community type Biophysical Settings name LANDFIRE 

Code

Shrubland, woodland, and 

forest—Continued

Southern Rocky Mountain Dry-Mesic Montane Mixed Conifer Forest and 

Woodland

10510

Southern Rocky Mountain Mesic Montane Mixed Conifer Forest and Woodland 10520

Southern Rocky Mountain Ponderosa Pine Woodland 10540

Southern Rocky Mountain Ponderosa Pine Woodland—South 10541

Southern Rocky Mountain Ponderosa Pine Woodland—North 10542

Rocky Mountain Subalpine Dry-Mesic Spruce-Fir Forest and Woodland 10550

Rocky Mountain Subalpine Mesic-Wet Spruce-Fir Forest and Woodland 10560

Rocky Mountain Subalpine-Montane Limber-Bristlecone Pine Woodland 10570

Southern Rocky Mountain Pinyon-Juniper Woodland 10590

Inter-Mountain Basins Aspen-Mixed Conifer Forest and Woodland 10610

Inter-Mountain Basins Aspen-Mixed Conifer Forest and Woodland—Low 

Elevation

10611

Inter-Mountain Basins Curl-leaf Mountain Mahogany Woodland and Shrubland 10620

Colorado Plateau Mixed Low Sagebrush Shrubland 10640

Inter-Mountain Basins Mat Saltbush Shrubland 10660

Rocky Mountain Alpine Dwarf-Shrubland 10700

Wyoming Basins Dwarf Sagebrush Shrubland and Steppe 10720

Chihuahuan Creosotebush Desert Scrub 10740

Chihuahuan Succulent Desert Scrub 10770

Inter-Mountain Basins Big Sagebrush Shrubland 10800

Inter-Mountain Basins Big Sagebrush Shrubland—Basin Big Sagebrush 10801

Inter-Mountain Basins Big Sagebrush Shrubland—Wyoming Big Sagebrush 10802

Mojave Mid-Elevation Mixed Desert Scrub 10820

Northwestern Great Plains Shrubland 10850

Rocky Mountain Lower Montane-Foothill Shrubland 10860

Rocky Mountain Lower Montane-Foothill Shrubland—No True Mountain 

Mahogany

10861

Rocky Mountain Lower Montane-Foothill Shrubland—True Mountain 

Mahogany

10862

Southern Colorado Plateau Sand Shrubland 10930

Apacherian-Chihuahuan Mesquite Upland Scrub 10950

Chihuahuan Mixed Desert and Thorn Scrub 11000

Chihuahuan Mixed Desert Shrubland 11002

Madrean Oriental Chaparral 11010

Colorado Plateau Pinyon-Juniper Shrubland 11020

Mogollon Chaparral 11040
10

Table 3. Community types for the estimated historical distribution of grasslands dataset and corresponding 

LANDFIRE Biophysical Settings names.—Continued

[LANDFIRE, Landscape Fire and Resource Management Planning Tools]

Community type Biophysical Settings name LANDFIRE 

Code

Shrubland, woodland, and 

forest—Continued

Rocky Mountain Gambel Oak-Mixed Montane Shrubland 11070

Sonora-Mojave Semi-Desert Chaparral 11080

Western Great Plains Mesquite Woodland and Shrubland 11110

Inter-Mountain Basins Juniper Savanna 11150

Madrean Juniper Savanna 11160

Southern Rocky Mountain Ponderosa Pine Savanna 11170

Southern Rocky Mountain Ponderosa Pine Savanna—South 11171

Southern Rocky Mountain Ponderosa Pine Savanna—North 11172

Southern Rocky Mountain Juniper Woodland and Savanna 11190

Inter-Mountain Basins Big Sagebrush Steppe 11250

Inter-Mountain Basins Montane Sagebrush Steppe 11260

Inter-Mountain Basins Semi-Desert Shrub-Steppe 11270

Inter-Mountain Basins Greasewood Flat 11530

Middle Rocky Mountain Montane Douglas-fir Forest and Woodland 11660

Northwestern Great Plains-Black Hills Ponderosa Pine Woodland and Savanna 11790

Northwestern Great Plains-Black Hills Ponderosa Pine Woodland and 

Savanna—Low Elevation Woodland

11791

Northwestern Great Plains-Black Hills Ponderosa Pine Woodland and 

Savanna—Savanna

11792

Crosstimbers Oak Forest and Woodland 13080

North-Central Interior Dry-Mesic Oak Forest and Woodland 13100

North-Central Interior Maple-Basswood Forest 13140

Edwards Plateau Limestone Savanna and Woodland 13830

Tamaulipan Calcareous Thornscrub 13920

Edwards Plateau Limestone Shrubland 13930

Edwards Plateau Dry-Mesic Slope Forest and Woodland 15230

Aquatic Open Water 11

Riparian and wetlands Rocky Mountain Bigtooth Maple Ravine Woodland 10120

North American Warm Desert Riparian Systems 11550

Rocky Mountain Montane Riparian Systems 11590

Rocky Mountain Subalpine/Upper Montane Riparian Systems 11600

Western Great Plains Floodplain Systems 11620

Northwestern Great Plains Canyon 13410

Western Great Plains Wooded Draw and Ravine 13850

Eastern Great Plains Floodplain Systems 14690
11

Table 3. Community types for the estimated historical distribution of grasslands dataset and corresponding 

LANDFIRE Biophysical Settings names.—Continued

[LANDFIRE, Landscape Fire and Resource Management Planning Tools]

Community type Biophysical Settings name LANDFIRE 

Code

Riparian and wetlands—

Continued

Central Interior and Appalachian Floodplain Systems 14710

Central Interior and Appalachian Riparian Systems 14720

Eastern Great Plains Wet Meadow–Prairie-Marsh 14880

Western Great Plains Depressional Wetland Systems 14950

Western Great Plains Depressional Wetland Systems—Playa 14951

Western Great Plains Depressional Wetland Systems—Saline 14952

Chihuahuan-Sonoran Desert Bottomland and Swale Grassland 15040

Chihuahuan-Sonoran Desert Bottomland and Swale Grassland—Tobosa 

Grassland

15041

Chihuahuan-Sonoran Desert Bottomland and Swale Grassland—Alkali Sacaton 15042

Edwards Plateau Riparian 15250

Sparsely vegetated Perennial Ice/Snow 12

Barren-Rock/Sand/Clay 31

Inter-Mountain Basins Sparsely Vegetated Systems 10010

North American Warm Desert Sparsely Vegetated Systems 10040

Rocky Mountain Alpine/Montane Sparsely Vegetated Systems 10060

Western Great Plains Sparsely Vegetated Systems 10070

Rocky Mountain Alpine Fell-Field 11430

Rocky Mountain Alpine Turf 11440

1

Cool season bunchgrass prairie was not classified as a result of the use of LANDFIRE data.

2

Several desert scrub types were reclassified as saline grasslands using data from the National Resources Conservation 

Service.

Products

Datasets associated with this report include a raster dataset in Tag Image File Format (.tif) 

representing the estimated historical distribution of grassland communities of the Southern Great Plains, 

the associated Federal Geographic Data Committee metadata in XML format, and a layer file (.lyr) used 

for cartographic display of the raster data (Callan and others, 2016).

Disclaimers

Any use of trade, firm, or product names is for descriptive purposes only and does not imply 

endorsement by the U.S. Government. Although these data have been processed successfully on a 

computer system at the USGS, no warranty expressed or implied is made regarding the display or utility 

of the data on any other system, or for general or scientific purposes, nor shall the act of distribution 

constitute any such warranty. The USGS shall not be held liable for improper or incorrect use of the data 

described and (or) contained herein. Maps provided within this document are not for navigational use.
12

Summary

This project mapped the estimated historical distribution of grassland communities of the 

Southern Great Plains Rapid Ecoregional Assessment (REA) project area prior to Euro-American 

settlement. We mapped the distribution of 10 grassland communities within the project area including 

shortgrass, mixed-grass, and sand prairies which are the dominant grassland communities evaluated for 

the REA. Community types were primarily classified using the plant species with the largest annual 

productivity as identified by the Natural Resources Conservation Service (NRCS). We also used 

Landscape Fire and Resource Management Planning Tools (LANDFIRE) classifications where NRCS 

data were unavailable and in peripheral watersheds intersecting an ecoregion boundary. Some 

ecological sites were classified from only a few vegetation plots; consequently, the estimated historical 

distribution of grasslands is best suited to regional- and landscape-level applications as a result of these 

and other data limitations inherent in estimating the historical distribution of grasslands. The 30 x 30-

meter raster dataset of the estimated historical distribution of grassland communities (Callan and others, 

2016) can be used to address management questions for the Southern Great Plains REA, Great Plains 

Landscape Conservation Cooperative, and other broad-scale management issues.

References Cited

Assal, T.J., Melcher, C.P., and Carr, N.B., eds., 2015, Southern Great Plains Rapid Ecoregional 

Assessment—Pre-assessment report: U.S. Geological Survey Open-File Report 2015−1003, 282 p.,

accessed June 23, 2016, at http://dx.doi.org/10.3133/ofr20151003.

Bryce, S.A., Strittholt, J.R. Ward, B.C., and Bachelet, D.M., 2012, Colorado Plateau Rapid Ecoregional

Assessment Report: Denver, Colo., Prepared for the U.S. Department of the Interior, Bureau of Land 

Management, 158 p.

Callan, Ramana, Leinwand, I.I.F., Reese, G.C., Assal, T.J., Manier, D.J., Carr, N.B., Burris, Lucy, 

Ignizio, D.A., 2016, Estimated historical distribution of grassland communities of the Southern Great 

Plains: U.S. Geological Survey data release, https://dx.doi.org/10.5066/F71Z42J3.

Carr, N.B., and Melcher, C.P., eds., 2015, Wyoming Basin Rapid Ecoregional Assessment: U.S. 

Geological Survey Open-File Report 2015–1155, 896 p., accessed June 23, 2016, at 

http://dx.doi.org/10.3133/ofr20151155.

Comer, P., Crist, P., Reid, M., Hak, J., Hamilton, H., Braun, D., Kittel, G., Varley, I., Unnasch, B., 

Auer, S., Creutzburg, M., Theobald, D., and Kutner, L., 2013, Central Basin and Range Rapid 

Ecoregional Assessment report: Denver, Colo., Prepared for the U.S. Department of the Interior, 

Bureau of Land Management, 168 p., accessed June 23, 2016, at

http://www.blm.gov/wo/st/en/prog/more/Landscape_Approach/reas/cbasinrange.html.

Elliot, L., 2010, Draft descriptions of systems, mapping subsystems, and vegetation types for Phase III: 

Columbia, Missouri, Missouri Resource Assessment Partnership, 86 p., accessed June 23, 2016, at 

http://www.cerc.usgs.gov/morap/Assets/UploadedFiles/Projects/Texas_Ecological_Systems_Classific

ation/Phase_3_Systems_Descriptions.pdf.

Epstein, H.E., Lauenroth, W.K., Burke, I.C., and Coffin, D.P., 1998, Regional productivities of plant 

species in the Great Plains of the United States: Plant Ecology, v.134, p.173–195. 

Landscape Fire and Resource Management Planning Tools, 2012, Biophysical Settings, LANDFIRE 

1.3.0: U.S. Department of Agriculture, Forest Service, and U.S. Department of the Interior, 

Geological Survey, accessed May 6, 2015, at 

http://www.landfire.gov/NationalProductDescriptions20.php.
13

Natural Resources Conservation Service, 2015a, Ecological Site Inventory System: Natural Resources 

Conservation Service, accessed July 2015 at https://esis.sc.egov.usda.gov.

Natural Resources Conservation Service, 2015b, Soil Survey Geographic Database, Natural Resources 

Conservation Service, accessed July 2015 at http://websoilsurvey.nrcs.usda.gov/.

Natural Resources Conservation Service, 2015c, The PLANTS database: Baton Rouge, La., National 

Plant Data Center, accessed July 2015 at http://plants.usda.gov.

Nelson, M.L., Brewer, K., and Solem, S.J., 2015, Existing vegetation classification, mapping and 

inventory technical guide version 2.0: Washington, D.C., U.S. Department of Agriculture, Forest 

Service General Technical Report WO-90, 212 p.

Omernik, J.M., 1987, Ecoregions of the conterminous United States [map supplement]: Annals of the 

Association of American Geographers, v. 77, no. 1, p. 118–125.

Reeves, M.C., Ryan, K.C., Rollins, M.G., and Thompson, T.G., 2009, Spatial fuel data products of the 

LANDFIRE project: International Journal of Wildland Fire, v. 18, p. 250–267.

Rollins, M.G., 2009, LANDFIRE—A nationally consistent vegetation, wildland fire, and fuel 

assessment: International Journal of Wildland Fire, v. 18, no. 3, p. 235–249.

Zerbe, S., 1998, Potential natural vegetation—Validity and applicability in landscape planning and 

nature conservation: Applied Vegetation Science, v. 1, no. 2, p. 165–172.

ISSN 2331-1258 (online)

https://doi.org/10.3133/ofr20161184