Professional Paper 1794–C

U.S. Department of the Interior

U.S. Geological Survey

Status and Trends of Land Change in the 

Midwest–South Central United States—1973 

to 2000

Professional Paper 1794–C

U.S. Department of the Interior

U.S. Geological Survey

Status and Trends of Land Change in 

the Midwest–South Central United 

States—1973 to 2000

Edited by Roger F. Auch and Krista A. Karstensen
U.S. Department of the Interior

SALLY JEWELL, Secretary

U.S. Geological Survey

Suzette M. Kimball, Acting Director

U.S. Geological Survey, Reston, Virginia: 2015

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://www.usgs.gov/pubprod/.

To order this and other USGS information products, visit http://store.usgs.gov/.

Any use of trade, product, or firm 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. 

ISSN 1044-9612 (print) 

ISSN 2330-7102 (online) 

http://dx.doi.org/10.3133/pp1794C

Suggested citation:

Auch, R.F., and Karstensen, K.A., eds., 2015, Status and trends of land change in the 

Midwest–South Central United States—1973 to 2000: U.S. Geological Survey Professional 

Paper 1794–C, 190 p., http://dx.doi.org/10.3133/pp1794C.

Cover:

Corn field and quonset barn on rolling land, with forested hills in background, south of 

Owensboro, Kentucky. Photograph by Thomas R. Loveland, 2003.

Inside cover:

Cattle grazing in less intensively used pasture northwest of El Dorado, Arkansas. Photograph by 

Mark A. Drummond, 2009.
iii

Foreword

This Professional Paper is the first multitemporal assessment of late-20th-century land change in 

the conterminous United States across all regions and all land-use and land-cover sectors. The work is the 

culmination of nearly 10 years of research and development by the U.S. Geological Survey, with support from 

the U.S. Environmental Protection Agency and the National Aeronautics and Space Administration, as well 

as university collaborators. It represents the most complete and comprehensive analysis of the rates, types, 

distribution, and drivers of recent changes in land use and land cover. The study bridges the gap between 

coarse-scale continental and global assessments and fine-scale local and regional case studies. 

Land-change studies attempt to explain the “what, where, when, how, and why” of changes to the 

vegetation and to the use of the land. Land-change research is aimed specifically at measuring where 

change is occurring (and where it is not occurring); which land-use and land-cover classes are changing (and 

what they are changing to); how much land is changing (and how fast); and what drivers are responsible 

for the measured changes. The goal is not only to understand the scope of change but also to provide the 

information base necessary to evaluate, predict, and manage the consequences of change.

Like many key issues in climate change and ecosystem functioning, land use and land cover are 

both drivers and indicators of environmental quality. The National Research Council has identified the 

understanding of land-use dynamics as one of the grand challenges for environmental research—no other 

global-change parameter is so tightly intertwined with issues of past, present, and future land-use practices, 

weather patterns, soil and carbon dynamics, ecosystem health and diversity, economic development and 

policy, technology issues, human population size and distribution, and overall human health. People and 

their use of the land are interrelated in complex ways, and the effects of land-use and land-cover change 

can have a huge impact on their quality of life, on the goods and services that they can expect from the 

land, and on the hazards that they may face. Despite these profound consequences, the Intergovernmental 

Panel on Climate Change’s Third Assessment Report has cited the lack of scientific understanding about the 

timing, magnitude, and direction of response of ecological, social, and economic systems to the combined 

effects of climate change and land-use and land-cover change as a key uncertainty in determining societal 

vulnerabilities and predicting both regional and global impacts of climate change.

Prior to this study, only sectorally specific or spatially limited assessments and inventories had been 

conducted to categorize land change in the United States. These efforts often included only certain land-use 

and land-cover classes or ownership categories, or they were conducted over short time intervals only, 

and integrating these various assessments into a comprehensive and consistent national synthesis of land 

change was not possible. The research presented in this Professional Paper has been specifically designed to 

provide the first comprehensive measurement of land-cover change in the conterminous United States. 

Relying on Landsat satellite imagery—the longest continuous and consistent dataset of synoptic Earth 

observations—the authors characterize changes across 11 primary land-use and land-cover classes spanning 

four time periods between 1973 and 2000. For each of these time periods and classes, estimates of change 

are developed for each of 84 distinct ecological regions—or ecoregions—across the conterminous United 

States.

The results provide useful, if not essential, information for understanding climate change, biodiversity, 

resource management and planning, resource security, and disaster planning. A significant conclusion is 

that no single profile of land-use and land-cover change exists. Numerous different, and often complex, 

interactions between an ecoregion’s socioeconomic drivers and its biological and physical characteristics 

have produced widespread regional and temporal variability in the rates, types, and total extent of land 

change. Among the scientific findings presented are estimates of overall forest decline in response to 

increased rates of disturbance, urbanization, and agricultural intensification. 

This research provides a critical ecoregional to national perspective of U.S. land change in the 

conterminous United States. With the completion of the 1973–2000 assessment, this study lays a foundation 

for understanding the Nation’s land-change dynamics and makes possible a new era for analyzing the 

consequences of land change, as well as for modeling future land changes.

Acting Director, USGS
iv

Preface

U.S. Geological Survey (USGS) Professional Paper 1794–C is the third in a four-volume series on 

the status and trends of the Nation’s land use and land cover, providing an assessment of the rates and 

causes of land-use and land-cover change in the Midwest–South Central United States between 1973 

and 2000. Volumes A, B, and D provide similar analyses for the Western United States, the Great Plains 

of the United States, and the Eastern United States, respectively. The assessments of land-use and 

land-cover trends are conducted on an ecoregion-by-ecoregion basis, and each ecoregion assessment is 

guided by a nationally consistent study design that includes mapping, statistical methods, field studies, 

and analysis. Individual assessments provide a picture of the characteristics of land change occurring in a 

given ecoregion; in combination, they provide a framework for understanding the complex national mosaic 

of change and also the causes and consequences of change. Thus, each volume in this series provides 

a regional assessment of how (and how fast) land use and land cover are changing, and why. The four 

volumes together form the first comprehensive picture of land change across the Nation.

Geographic understanding of land-use and land-cover change is directly relevant to a wide variety 

of stakeholders, including land and resource managers, policymakers, and scientists. The chapters that 

follow present brief summaries of the patterns and rates of land change observed in each ecoregion in the 

Midwest–South Central United States, together with field photographs, statistics, and comparisons with 

other assessments. In addition, a synthesis chapter summarizes the scope of land change observed across 

the entire Midwest–South Central United States. The studies provide a way of integrating information across 

the landscape, and they form a critical component in the efforts to understand how land use and land cover 

affect important issues such as the provision of ecological goods and services and also the determination 

of risks to, and vulnerabilities of, human communities. Results from this project also are published in peerreviewed journals, and they are further used to produce maps of change and other tools for land management, as well as to provide inputs for carbon-cycle modeling and other climate change research.

This report is only one of the products produced by USGS on land-use and land-cover change in the 

United States. Other reports and land-cover statistics are available online at http://landcovertrends.usgs.gov. 

Acknowledgments

The U.S. Environmental Protection Agency’s Office of Research and Development and the National 

Aeronautics and Space Administration provided initial funding to support this project. 

The U.S. Geological Survey’s (USGS) Geographic Analysis and Monitoring Program and Climate and 

Land Use Change Research and Development Program provided long-term support for this research.

Adam Davis (USGS) provided extensive support in the production of figures and tables.

All photographs contained within this Professional Paper were taken by various members of the 

Land Cover Trends research project while conducting field investigations between 1999 and 2010.

Author Affiliations

Roger F. Auch

Christopher A. Barnes

Mark S. Brooks

Mark A. Drummond

Robert P. Glover

Steven Kambly

Krista A. Karstensen

Christy L. Ryan

Kristi L. Sayler

Daniel G. Sorenson

Janis L. Taylor

Tamara S. Wilson

U.S. Geological Survey

ASRC Federal InuTeq

U.S. Geological Survey

U.S. Geological Survey

U.S. Geological Survey

U.S. Geological Survey

U.S. Geological Survey

U.S. Geological Survey

U.S. Geological Survey

U.S. Geological Survey

Stinger Ghaffarian Technologies

U.S. Geological Survey
v

Contents

Foreword........................................................................................................................................................iii

Preface...........................................................................................................................................................iv

Acknowledgments........................................................................................................................................iv

Author Affiliations.........................................................................................................................................iv

Regional Synthesis

Land-Cover Trends in the Midwest–South Central United States—1973 to 2000.......................3

 By Roger F. Auch, Krista A. Karstensen, and Steven Kambly

Northern Forests Ecoregions

1. Northern Minnesota Wetlands Ecoregion...............................................................................25

By Kristi L. Sayler

2. Northern Lakes and Forests Ecoregion....................................................................................33

By Tamara S. Wilson and Christy L. Ryan 

Northern Agriculture-Forest Transition Zone Ecoregions

3. North Central Hardwood Forests Ecoregion...........................................................................45

By Christopher A. Barnes

4. Driftless Area Ecoregion.............................................................................................................53

By Robert P. Glover

5. Southern Michigan/Northern Indiana Drift Plains Ecoregion...............................................61

By Steven Kambly

6. Erie Drift Plains Ecoregion..........................................................................................................69

By Janis L. Taylor

Midwest Agricultural Ecoregions

7. Southeastern Wisconsin Till Plains Ecoregion.......................................................................81

By Mark S. Brooks

8. Huron/Erie Lake Plains Ecoregion.............................................................................................89

By Steven Kambly

9. Eastern Corn Belt Plains Ecoregion..........................................................................................97

By Roger F. Auch

10. Central Corn Belt Plains Ecoregion.........................................................................................107

By Daniel G. Sorenson

11. Interior River Lowland Ecoregion............................................................................................115

By Krista A. Karstensen and Roger F. Auch

South Central Highlands Ecoregions

12. Ozark Highlands Ecoregion......................................................................................................125

By Krista A. Karstensen

13. Boston Mountains Ecoregion..................................................................................................135

By Krista A. Karstensen

14. Arkansas Valley Ecoregion.......................................................................................................143

By Krista A. Karstensen

15. Ouachita Mountains Ecoregion................................................................................................151

By Krista A. Karstensen

South Central Lowlands Ecoregions

16. Mississippi Alluvial Plain Ecoregion.......................................................................................161 

- By Kristi L. Sayler

17. South Central Plains Ecoregion...............................................................................................169

By Mark A. Drummond
vi

Conversion Factors

Inch/Pound to SI Multiply by To obtain

Length

inch (in.) 2.54 centimeter (cm)

inch (in.) 25.4 millimeter (mm)

foot (ft) 0.3048 meter (m)

mile (mi) 1.609 kilometer (km)

Area

acre 4,047 square meter (m2

)

acre 0.4047 hectare (ha)

acre 0.004047 square kilometer (km2

)

square mile (mi2

) 2.590 square kilometer (km2) 

Temperature in degrees Celsius (°C) may be converted to degrees Fahrenheit (°F) as follows: °F=(1.8×°C)+32

Temperature in degrees Fahrenheit (°F) may be converted to degrees Celsius (°C) as follows: °C=(°F-32)/1.8

Appendix 1. Map of Ecoregions in Conterminous United States....................................................179

Appendix 2. Abbreviations for Ecoregions in the Midwest–South Central United States.........182

Appendix 3. Land-Cover Classification System Used in “Status and Trends of Land 

 Change” Study..........................................................................................................................183

Appendix 4. Methodology Used in “Status and Trends of Land Change” Study..........................184
Regional Synthesis1

Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000 

Edited by Roger F. Auch and Krista A. Karstensen 

U.S. Geological Survey Professional Paper 1794–C, 2015

Land-Cover Trends in the Midwest–South Central 

United States—1973 to 2000

By Roger F. Auch, Krista A. Karstensen, and Steven Kambly

Introduction

The Midwest–South Central United States is one of four 

major regions of the conterminous United States that were 

studied in the U.S. Geological Survey’s “Status and Trends of 

Land Change” study. This research activity provides a holistic 

appraisal of contemporary land-use/land-cover change across 

the nation, filling a research niche that could not be supported 

by current resource inventories that are based on thematic land 

categories and ownership (Loveland and Acevedo, 2006). The 

U.S. Geological Survey, supported by the U.S. Environmental 

Protection Agency and the National Aeronautics and Space 

Administration, initiated the “Status and Trends of Land Change” 

study to better understand the spatial and temporal dimensions, 

as well as the consequences, of national land-use and land-cover 

change in the late 20th century (Loveland and others, 2002). 

The “Status and Trends of Land Change” study used landuse/land-cover mapping derived from Landsat satellite imagery 

(and supported by higher resolution aerial photography), a 

statistical sampling strategy (Stehman and others, 2003), and 

geographic regionalization to provide information on the types, 

amounts, and rates of land change in the United States (Loveland 

and others, 2002). Level III ecoregions (U.S. Environmental 

Protection Agency, 1999) were selected as the geographic 

framework for the study because they have homogenous 

conditions of similar land forms, soils, vegetation, and land use.

The Midwest–South Central United States region 

contains 17 distinct ecoregions. Each ecoregion was gridded, 

then a random selection of “sample blocks” was drawn, the 

population size being determined by the expected amount of 

change (Loveland and others, 2002). The sample-block size for 

the 17 Midwest–South Central United States ecoregions was 

10×10 km. Sampling allowed intense manual interpretation at

the local scale (Sohl and others, 2004; Auch and others, 2012) 

that could be aggregated to broader scales, such as Level III 

ecoregions, to give statistically rigorous estimates of land-use 

and land-cover change. The interpretation of Landsat imagery 

across five study dates (1973, 1980, 1986, 1992, and 2000) 

provided the basis for creating land-use/land-cover maps for 

each sample block. Land use and land cover were classified 

using a modified Anderson Level I system (Anderson and 

others, 1976; Loveland and others, 2002) of 11 categories (see 

appendix 3 for definitions of land-use/land-cover classifications). 

The size of the minimum mapping unit was 60 × 60 m to allow 

for comparison between earlier Multispectral Scanner (MSS) 

sensor data and finer resolution imagery (30 × 30 m) of the 

Thematic Mapper (TM) and Enhance Thematic Mapper (ETM) 

sensors. Land-use/land-cover maps created from TM and ETM 

imagery were resampled to 60-m resolution.

The Midwest–South Central United States stretches from 

the northern forests of the Great Lakes area south to the bird’s 

foot delta of the Mississippi River in Louisiana, and from the 

southern shore of Lake Erie in the northeast to the pine forests 

of east Texas in the southwest. Several distinguishing landcover patterns emerge when looking at the Midwest–South 

Central United States. The ecoregions of the far-northern and 

southwestern parts of the region are dominated by forest, 

whereas the remaining ecoregions are either predominately 

agricultural or a combination of both agricultural and forest lands 

(fig. 1A). This region also includes what commonly is called the 

“industrial Midwest,” an area whose growth historically has been 

based on transportation assets and manufacturing. The industrial 

Midwest is bracketed in the east by Cleveland and other cities in 

Ohio, in the northwest by the Minneapolis–Saint Paul region in 

Minnesota, in the north by Detroit and other cities in Michigan, 

and in the southwest by Saint Louis, Missouri (Auch and others, 

2006). Large urban centers north or south of the industrial 

Midwest are few, if present at all (fig. 1A). The variability of 

recent land-use/land-cover change and stability in the Midwest–

South Central United States has been based primarily on the 

major resources and settlement patterns of the region. These 

have included metropolitan growth, forest-management activities 

(wood harvest and forest regrowth), and agricultural stability, 

rearrangement, and intensification. This report discusses the 

aggregate changes in the Midwest–South Central United States 

during the entire study period (1973–2000), and it also presents 

greater detail in the 17 individual ecoregion summaries in the 

chapters that follow.

Regional Synthesis 

The Midwest–South Central United States region, 

which includes 17 ecoregions, encompasses 1,267,606 km2

(489,425mi2) in all or part of 19 states. For purposes of 

discussion, the 17 Midwest–South Central United States 
4 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Figure 1. A, Map of all 17 ecoregions in Midwest–South Central United States, showing land-use/land-cover classes from 1992 

National Land-Cover Database (Vogelmann and others, 2001); note that, for this “Status and Trends of Land Change” study, transitional 

land-cover class was subdivided into mechanically disturbed and nonmechanically disturbed classes. B, Map showing five main 

Midwest–South Central United States ecoregion groups, modified from U.S. Environmental Protection Agency’s (2010) Level II 

Ecoregions for Midwest–South Central United States. Within each ecoregion group, individual ecoregions share many similar physical, 

biological, and land-use characteristics. C, List of five main Midwest–South Central United States ecoregion groups depicted in figure 

1B; also listed are individual ecoregions included in each ecoregion group, as well as ecoregion abbreviations used in figure 1A.

95° 90° 85° 80°

45°

40°

35°

30°

Ecoregion boundary

State boundary

Land-use/land-cover class

EXPLANATION

Water

Developed

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Transitional

0 100 200 300 MILES

0 200100 300 KILOMETERS

Lake Superior

Lake Erie

Lake 

Huron

Lake 

Ontario

Lake Michigan

NLF

SCP

OH

MAP

IRL

CCBP

DA

ECBP

NCHF

AV

SMNIDP

OM

EDP

BM

NMW

SEWTP

HELP

NLF

HELP

Gulf of Mexico

CANADA
Land-Cover Trends in the Midwest–South Central United States—1973–2000 5

B

Northern Forests Ecoregions

NMW – Northern Minnesota Wetlands Ecoregion

NLF – Northern Lakes and Forests Ecoregion

Northern Agriculture-Forest Transition Zone Ecoregions

NCHF – North Central Hardwood Forests Ecoregion

DA – Driftless Area Ecoregion

SMNIDP – Southern Michigan/Northern Indiana Drift 

 Plains Ecoregion

EDP – Erie Drift Plains Ecoregion

Midwest Agricultural Ecoregions

SEWTP – Southeastern Wisconsin Till Plains Ecoregion

HELP – Huron/Erie Lake Plains Ecoregion

ECBP – Eastern Corn Belt Plains Ecoregion

CCBP – Central Corn Belt Plains Ecoregion

IRL – Interior River Lowland Ecoregion

South Central Highlands Ecoregions

OH – Ozark Highlands Ecoregion

BM – Boston Mountains Ecoregion

AV – Arkansas Valley Ecoregion

OM – Ouachita Mountains Ecoregion

South Central Lowlands Ecoregions

MAP – Mississippi Alluvial Plain Ecoregion

SCP – South Central Plains Ecoregion

C EXPLANATION

Northern Forests

South Central

Highlands

South Central

Lowlands

Northern AgricultureForest Transition Zone

Midwest Agricultural

Figure 1.—Continued.

ecoregions have been divided into five main groups, within which 

the ecoregions share many similar physical, biological, and landuse characteristics: the Northern Forests Ecoregions, the Northern 

Agriculture-Forest Transition Zone Ecoregions, the Midwest Agricultural Ecoregions, the South Central Highlands Ecoregions, and 

the South Central Lowlands Ecoregions (fig. 1B).

The leading land-cover classes in the Midwest–South 

Central United States during the study period (1973–2000) 

were agriculture and forest (table 1). Combined, they made up 

an estimated 80.5 percent of the region’s land area in 1973. 

By 2000, agriculture decreased by 0.9 percent, and forest 

decreased by 1.9 percent. Loss of forest land cover was due 

primarily to timber cutting, which is reflected in the doubling 

of mechanically disturbed land, from 0.7 percent of the land 

area in 1973 to 1.7 percent in 2000. Forest also was converted 

to agricultural and developed land. Loss of farmland largely 

was the result of conversion to developed land, as well as, 

to a lesser degree, to grassland/shrubland. Wetland, the third 

most extensive land-cover class in the region, accounted for 

8.9 percent of the area in 1973 but decreased to 8.5 percent by 

1992; much of this decrease can be attributed to conversions 

to water and agricultural land.

The overall spatial change (the percentage of land area that 

changed at least one time from one land-cover class to another) 

in the Midwest–South Central United States was 9.9 percent

(about 125,420 km2). About 5.6 percent of the land area changed 

only once during the study period, whereas 3.3 percent and 

0.9 percent changed two and three times, respectively. A small 

amount of land (0.09 percent) changed four times. Land that 

changed multiple times most likely reflected the cyclical nature 

of certain types of change such as forest management, in which 

timber cutting and regeneration may have occurred on the same 

land several times between 1973 and 2000. 

Although the overall spatial change for the Midwest–

South Central United States was 9.9 percent, a few ecoregions 

had much greater amounts of spatial change. The Ouachita 
6 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Mountains, South Central Plains, and Northern Lakes and 

Forests Ecoregions each exceeded the region’s percentage of 

overall spatial change (fig. 2; table 2). Most of the change in 

these ecoregions, which include forested land in Arkansas, 

Oklahoma, Louisiana, Texas, Minnesota, Wisconsin, and 

Michigan, was related to timber cutting and regrowth. 

Ecoregions whose overall spatial change was substantially less 

than that of the region generally were agricultural ones such as 

the Southern Michigan/Northern Indiana Drift Plains, Central 

Corn Belt Plains, and Huron/Erie Lake Plains Ecoregions. 

The leading land-cover conversion in these ecoregions was 

agriculture to developed. The ecoregion that experienced the 

lowest amount of change, the Driftless Area Ecoregion, was 

predominantly agricultural, having only limited increases in 

developed land. 

Overall spatial change also is evident in the ecoregion 

groups (fig. 1B), which have been subdivided on the basis of 

their similar land-cover compositions (fig. 1A) and topography. 

Ecoregion groups that, in general, have level to undulating 

topography and limited amount of forested land (for example, 

the Midwest Agricultural Ecoregions and the Northern 

Agriculture-Forest Transition Zone Ecoregions) tend to be 

dominated by agriculture, and they experienced moderate 

amounts of change (table 2). Ecoregion groups in which forest 

was the principal land-cover class, such as the Northern Forests 

Ecoregions, the South Central Lowlands Ecoregions, and the 

South Central Highlands Ecoregions, experienced greater 

amounts of change, nearly double that of the highly agricultural 

ecoregion groups. In terms of large amounts of land-cover 

change, the Ouachita Mountains Ecoregion (33.9percent

change), in the South Central Highlands Ecoregions group, and 

the South Central Plains Ecoregion (27.1 percent change), in 

Land-use/land-cover class

1973

[margin of error] 

(% of area)

1980

[margin of error] 

(% of area)

1986

[margin of error] 

(% of area)

1992

[margin of error] 

(% of area)

2000

[margin of error] 

(% of area)

Water 5.2 [1.2] 5.3 [1.2] 5.5 [1.2] 5.5 [1.2] 5.6 [1.2]

Developed 3.6 [0.5] 3.9 [0.6] 4.2 [0.6] 4.5 [0.6] 5.1 [0.7]

Mechanically disturbed 0.7 [0.1] 1.0 [0.2] 1.4 [0.2] 1.2 [0.2] 1.7 [0.2]

Mining 0.1 [0.1] 0.1 [<0.1] 0.1 [<0.1] 0.2 [<0.1] 0.2 [<0.1]

Barren <0.1 [<0.1] <0.1 [<0.1] <0.1 [<0.1] <0.1 [<0.1] <0.1 [<0.1]

Forest 37.5 [1.2] 36.8 [1.1] 36.2 [1.1] 36.1 [1.1] 35.7 [1.1]

Grassland/Shrubland 1.1 [0.2] 1.2 [0.2] 1.4 [0.2] 1.5 [0.2] 1.3 [0.2]

Agriculture 42.9 [1.4] 42.9 [1.4] 42.8 [1.4] 42.5 [1.4] 42.0 [1.4]

Wetland 8.9 [0.9] 8.7 [0.8] 8.6 [0.8] 8.6 [0.8] 8.5 [0.8]

Nonmechanically disturbed 0.0 [<0.1] <0.1 [<0.1] 0.0 [0.0] 0.0 [<0.1] <0.1 [<0.1]

Table 1. Areal percentages of land-use/land-cover classes in all 17 Midwest–South Central United States 

ecoregions for each of five study years (1973, 1980, 1986, 1992, 2000) and corresponding margin-of-error values 

for 85-percent confidence interval (in brackets).

[Percentages are of total area in all Midwest–South Central United States ecoregions. See appendix 3 for definitions of land-use/landcover classifications]

the South Central Lowlands Ecoregions group, could have been 

placed together to form a new ecoregion group, the “Industrial 

Southern Pine Forestry Ecoregions” group. Although ecoregion 

groups present an interesting scale concept to envision, the rest 

of this report concentrates on the greater Midwest–South Central 

United States region and the 17 ecoregions within it. 

No single story of land-use/land-cover change in the 

Midwest–South Central United States during the 27-year 

(1973–2000) study period has emerged. Forest harvest 

(and subsequent regrowth) was the major driver of change 

in some ecoregions, whereas in others it was continued 

urbanization of farmland; in still others, economic stimuli and 

governmental farm policy were the main drivers of change, 

resulting in the expansion, contraction, or adjustment of 

agricultural land. For example, in the Mississippi Alluvial 

Plain Ecoregion, several unique stories of change were 

observed, including the loss of coastal-marsh wetlands to 

water and also, to a lesser extent, the clearing of bottomland 

hardwood forests (forested wetlands) to agricultural land. 

Although both of these losses were to the wetland land-cover 

class, they resulted in gains by two different land-cover 

classes, and they were for different reasons. 

Land-use/land-cover change in the Midwest–South 

Central United States during the 27-year study period can 

be assessed in several different ways, such as net and gross 

changes in individual land-cover classes. Net change is the 

total amount of losses in a land-cover class subtracted from 

the total amount of gains, a measure of the difference in land 

cover between two points in time (Loveland and Acevedo, 

2006). Gross change is the total area gained and lost in a 

particular land-cover class (Loveland and Acevedo, 2006). 

If all land-cover change occurred only one time in the same 
Land-Cover Trends in the Midwest–South Central United States—1973–2000 7

Lake Erie

Lake 

Ontario

NLF

NLF

SCP

OH

MAP

IRL

CCBP

DA

ECBP

NCHF

AV

SMNIDP

OM

EDP

BM

NMW

SEWTP

HELP

HELP

95° 90° 85° 80°

45°

40°

35°

30°

0 100 200 300 MILES

0 200100 300 KILOMETERS

Lake Superior

Lake 

Huron

Lake Michigan

Gulf of Mexico

CANADA

Overall Spatial Change

1.8–3.4

3.4–4.6

4.6–6.3

6.3–12.2

12.2–33.9

Figure 2. Map showing overall spatial change, as percent of ecoregion area, 

for each of 17 Midwest–South Central United States ecoregions over entire study 

period (1973–2000).
8 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Table 2. Overall spatial change in each Midwest–South Central United States ecoregion (in square 

kilometers and as percent of ecoregion) for entire study period (1973 to 2000) and corresponding margin-oferror values for 85-percent confidence interval (in brackets).

Ecoregion Ecoregion 

area (km2)

Overall spatial change [margin of error]

(km2) (% of ecoregion)

Northern Forests Ecoregions

Northern Minnesota Wetlands Ecoregion 24,427 2,003 [562] 8.2 [2.3]

Northern Lakes and Forests Ecoregion 189,889 23,166 [3,988] 12.2 [2.1]

Totals 214,316 25,169 [4,072] 11.7 [1.9]

Northern Agriculture-Forest Transition Zone Ecoregions

North Central Hardwood Forests Ecoregion 91,205 4,195 [1,277] 4.6 [1.4]

Driftless Area Ecoregion 47,590 857 [238] 1.8 [0.5]

Southern Michigan/Northern Indiana Drift Plains Ecoregion 73,987 3,107 [666] 4.2 [0.9]

Erie Drift Plains Ecoregion 30,622 1,868 [429] 6.1 [1.4]

Totals 243,403 10,027 [1,460] 4.1 [0.6]

Midwest Agricultural Ecoregions

Southeastern Wisconsin Till Plains Ecoregion 30,999 1,767 [403] 5.7 [1.3]

Huron/Erie Lake Plains Ecoregion 27,362 739 [219] 2.7 [0.8]

Eastern Corn Belt Plains Ecoregion 83,533 5,263 [2,255] 6.3 [2.7]

Central Corn Belt Plains Ecoregion 98,794 3,359 [1,186] 3.4 [1.2]

Interior River Lowland Ecoregion 93,272 5,130 [1,399] 5.5 [1.5]

Totals 333,960 16,257 [3,006] 4.9 [0.9]

South Central Highlands Ecoregions

Ozark Highlands Ecoregion 108,332 6,392 [758] 5.9 [0.7]

Boston Mountains Ecoregion 17,068 939 [154] 5.5 [0.9]

Arkansas Valley Ecoregion 26,606 2,208 [372] 8.3 [1.4]

Ouachita Mountains Ecoregion 26,506 8,985 [1,378] 33.9 [5.2]

Totals 178,512 18,524 [1,607] 10.4 [0.9]

South Central Lowlands Ecoregions

Mississippi Alluvial Plain Ecoregion 141,895 13,338 [3,831] 9.4 [2.7]

South Central Plains Ecoregion 155,520 42,146 [5,288] 27.1 [3.4]

Totals 297,415 55,484 [6,543] 18.7 [2.2]

All Midwest–South Central United States ecoregions 1,267,606 125,462 [8,873] 9.9 [0.7]

area, then net change and gross change would be the same. 

But a number of land-cover classes tended to change multiple 

times in the same area over time. For example, a stand of 

forest might be cut for timber harvest, then it would be 

restocked either actively or passively with young trees, and 

finally it could return to forest conditions, all during two or 

three time periods. Another example might be an agricultural 

field that changed land-use classes more than one time and 

then slowly returned to forest. The difference between gross 

and net change in a land-cover class in which most change is 

unidirectional (for example, to developed) tends to be small. 

The difference between gross and net change is large in landcover classes in which cyclic or multiple changes affect the 

status of that land cover (for example, forest). A clearer picture 

of overall change emerges by examining both gross and net 

changes (table 3).

The five land-cover classes that had the highest gross 

spatial change over the entire study period (1973–2000) are as 

follows:

•	 Forest, 92,868 km2 (margin of error, 7,366 km2)

•	 Mechanically disturbed, 68,613 km2 (margin of error, 

7,022 km2)

•	 Agriculture, 37,241 km2 (margin of error, 3,193 km2)

•	 Grassland/shrubland, 26,560 km2 (margin of error, 

2,882km2)

•	 Developed, 18,793 km2 (margin of error, 3,046 km2)

The five land-cover classes that had the largest net areal 

change (either gains or losses) over the entire study period 

(1973–2000) are as follows:

•	 Forest, −23,094 km2 (margin of error, 3,215 km2)

•	 Developed, 18,513 km2 (margin of error, 3,052 km2)
Land-Cover Trends in the Midwest–South Central United States—1973–2000 9

•	 Mechanically disturbed, 12,187 km2 (margin of error, 

2,517 km2)

•	 Agriculture, −11,706 km2 (margin of error, 3,124 km2)

•	 Water, 4,651 km2 (margin of error, 2,881 km2)

A summary of net areal change in each land-cover class 

for each time period can be found in table 4. Discussions of 

individual land-cover classes follow.

Forest Land-Cover Class

Forest experienced the largest amount of change of 

any land-cover class in the Midwest–South Central United 

States during the 27-year study period. Forest decreased by 

23,094 km2 between 1973 and 2000, a 4.9 percent decrease 

(table 3). The gross change in forest was much higher, at 

92,868 km2 (table3). Only two ecoregions, the Driftless

Area Ecoregion and the Southeastern Wisconsin Till Plains 

Ecoregion, had almost the same amounts of forest land cover 

in 2000 as in 1973. The other 15 Midwest–South Central 

United States ecoregions all had less forest land cover (as an 

areal percentage) in 2000 than in 1973. 

The story of the loss of forested land in the Midwest–

South Central United States ecoregions is more complex 

than it may appear to be. The two ecoregions that had the 

greatest percentage of forest decline, the Ouachita Mountains 

Ecoregion (−5.7 percent) and the South Central Plains Ecoregion (−4.9 percent), also were the forest-harvest areas that 

practiced the most cyclic silviculture methods. Most of the 

land that was mapped as having been logged (mechanically 

disturbed land-cover class) in 2000 most likely will revert 

to forest land cover in a short time span, perhaps five or six 

years in the future. Decreases in forest land cover in the primary wood-harvesting ecoregions that were mapped in 2000 

indicate that timber cutting had intensified, and the amount 

of area affected had grown, when compared to earlier dates 

in the study period. 

Forest was also lost to other major land-cover classes 

during the study period. Forest had a net loss to agriculture 

across all four time periods, but the loss was most pronounced 

between 1973 and 1986 when contemporary agricultural land 

use still was generally expanding in several ecoregions, such 

as the Ozark Highlands Ecoregion. The net gain in agriculture 

from forest in the Midwest–South Central United States (an 

estimated 5,498 km2) may represent a more permanent loss of 

forested land, but, if land uses change again, passive or active 

afforestation may occur on this agricultural land, and it again 

may return to forest. Conversion of forest to developed (an 

estimated 4,531 km2) was a permanent loss because of the 

unidirectional nature of this type of change. 

Wood harvesting (forest to mechanically disturbed;figs.

3A,B) was the leading type of land-cover change in the 

Midwest–South Central United States during the study 

period, at an estimated 62,212 km2. Most of this type of 

change occurred only one time on the same land, but in 

the two ecoregions that were heavily engaged as part of 

industrial southern-pine region (the South Central Plains and 

Ouachita Mountains Ecoregions), some areas were harvested 

twice during the study period; thus, the actual footprint of 

land impacted was less than the overall area that was cut. 

Other leading ecoregions for forest harvest include the 

Northern Lakes and Forests, Mississippi Alluvial Plain, and 

Table 3. Gross spatial changes and net areal changes in land-use/land-cover classes in all 

17 Midwest–South Central United States ecoregions for entire study period (1973 to 2000) and 

corresponding margin-of-error values for 85-percent confidence (in brackets).

[Percentages are of total area in all Midwest–South Central United States ecoregions. See appendix 3 for definitions 

of land-use/land-cover classifications] 

Land-use/land-cover class

Gross spatial change (1973–2000)

[margin of error]

Net areal change (1973–2000)

[margin of error]

(km2) (% of area) (km2) (% change)

Water 9,699 [982] 0.8 [0.1] 4,651 [2,881] 7.1

Developed 18,793 [3,046] 1.5 [0.2] 18,513 [3,052] 40.6

Mechanically disturbed 68,613 [7,022] 5.4 [0.6] 12,187 [2,517] 134.3

Mining 2,304 [613] 0.2 [<0.1] 750 [463] 48.8

Barren 593 [231] <0.1 [<0.1] −117 [105] −22.0

Forest 92,868 [7,366] 7.3 [0.6] −23,094 [3,215] −4.9

Grassland/Shrubland 26,560 [2,882] 2.1 [0.2] 2,930 [1,222] 21.7

Agriculture 37,241 [3,193] 2.9 [0.3] −11,706 [3,124] −2.2

Wetland 12,496 [1,367] 1.0 [0.1] −4,208 [2,817] −3.8

Nonmechanically disturbed 684 [907] 0.1 [0.1] 94 [122] 0.0
10 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Northern Minnesota Wetlands Ecoregions. Because of its 

much larger size, the Northern Lakes and Forests Ecoregion 

actually had more forest land harvested than did the Ouachita 

Mountains Ecoregion, but the cutting intensity was less 

than one-half of that of the Ouachita Mountains Ecoregion. 

Mechanically disturbed land-cover class was one to three 

percent of the Northern Lakes and Forests Ecoregion during 

the study period, whereas it was 4 to nearly 10 percent 

of the Ouachita Mountains Ecoregion during that same 

time period. The primary tree species targeted for “evenage management” harvesting (that is, clearcutting) in the 

southern Midwest–South Central United States ecoregions 

include loblolly and shortleaf pine (Pinus taeda and Pinus 

echinata, respectively) (see, for example, Bentley and others, 

2002) and, in the northern Midwest–South Central United 

States ecoregions, aspen (Populus tremuloides, Populus 

grandidentata), birch (Betula spp.), and various conifer 

species (Pinus spp., Picea spp., Abies balsamea, Tsuga 

canadensis, Larix laricina) (see, for example, Reading and 

Krantz, 2002). 

Forest regrowth directly from harvest (mechanically 

disturbed to forest) was the second leading type of landcover change during the study period, at an estimated 

35,426km2. Most of this rapid forest regeneration occurred 

in the southern ecoregions, where suitable tree-growing 

sites were planted with pine; it took place in many aspengrowing areas of the northern ecoregions as well. Aspen, 

which regenerates from its root stocks, quickly regrows 

after cutting. Aspen had not been considered as a major 

commercial tree species until the World War II era when it 

was determined that it could be pulped for paper production; 

more recently, aspen has been used as a component of 

oriented strand board construction panels (Lamb, 1967; 

Structural Board Association, 1999). 

Figure 3. Recently harvested forested areas in Midwest–South 

Central United States (forest to mechanically disturbed land-use/

land-cover change). A, Close-up view of clearcut area in Ouachita 

Mountains Ecoregion. B, Clearcut hillside in distance in Northern 

Lakes and Forests Ecoregion.

A

B

Table 4. Net areal changes in land-use/land-cover classes in all 17 Midwest–South Central United 

States ecoregions during each of four time periods and corresponding margin-of-error values for 

85-percent confidence (in brackets). 

[See appendix 3 for definitions of land-use/land-cover classifications]

Land-use/land-cover class Net change [margin of error] (km2)

1973–1980 1980–1986 1986–1992 1992–2000

Water 1,915 [1,823] 1,362 [775] 989 [420] 385 [642]

Developed 3,677 [861] 3,454 [573] 3,821 [662] 7,562 [1,554]

Mechanically disturbed 3,188 [2,041] 4,841 [2,157] −1,506 [1,900] 5,664 [1,931]

Mining 48 [101] 98 [107] 292 [226] 312 [395]

Barren −44 [47] −58 [70] −81 [89] 66 [81]

Forest −9,070 [2,231] −8,512 [2,230] −982 [2,006] −4,530 [2,355]

Grassland/Shrubland 1,801 [767] 1,982 [1,124] 1,535 [1,236] −2,388 [1,088]

Agriculture 103 [1,058] −1,079 [736] −4,000 [857] −6,730 [1,494]

Wetland −2,233 [1,784] −1,476 [836] −109 [431] −389 [697]

Nonmechanically disturbed 616 [881] −612 [881] 42 [66] 48 [139]
Land-Cover Trends in the Midwest–South Central United States—1973–2000 11

Figure 4. Forest regrowth after harvesting, leaving intermediate landscape of young trees, in Midwest–South Central United States. 

A, Regenerating stand of aspen in Northern Minnesota Wetlands Ecoregion. B, Young pines in grassy field in South Central Plains 

Ecoregion. 

A B

Another estimated 14,577 km2 of harvested forest 

reverted to grassland/shrubland (mechanically disturbed to 

grassland/shrubland; figs. 4A,B). The Northern Lakes and 

Forests Ecoregion, probably influenced by a shorter growing season, was the leader in this type of land-cover change 

(an estimated 6,140 km2), but the South Central Plains and 

Ouachita Mountains Ecoregions also experienced substantial 

amounts of this type of conversion. Less optimal site conditions, such as soils that were less suitable for tree growth, 

may be reason for slower forest regeneration in certain areas. 

Former agricultural land also became forested land in 

the Midwest–South Central United States during the study 

period. A rapid conversion from agriculture to forest affected 

an estimated 4,359 km2, the leading ecoregion being the South 

Central Plains Ecoregion (an estimated 1,895 km2), followed 

distantly by the Mississippi Alluvial Plain and North Central 

Hardwood Forests Ecoregions. A mixture of both active and 

passive afforestation on suitable tree-growing sites (the result 

of land uses changing away from farming and ranching) most 

likely was the reason behind this type of change. Agricultural 

land also could change to forested land through several steps 

that include an intermediate grassland/shrubland stage. It is 

difficult to determine how much agricultural land went through 

an intermediate step before becoming forested land because 

the amount of grassland/shrubland-to-forest change also 

includes land that had changed from mechanically disturbed to 

grassland/shrubland at an earlier date. An estimated 16,233km2

of land that converted from grassland/shrubland to forest 

during the study period came from harvested forest land that 

regenerated more slowly and also former agricultural land. The 

leading ecoregions for this type of land-cover change included 

the South Central Plains Ecoregion (an estimated 5,201 km2) 

and the Northern Lakes and Forests Ecoregion (5,030 km2). 

Grassland/shrubland was the only land-cover class that 

had a net loss to forest. Almost all other land-cover classes had 

net gains from forest (fig. 5), as indicated by the overall net 

decrease in the forest land-cover class during the study period.

12

10

8

6

4

2

0

–2

–4

–6

–8

–10

–12

1973–1980 1980–1986 1986–1992 1992–2000

Area changed, in thousands of square kilometers

Time period

Water

Developed

Mechanically disturbed

Mining

Barren

Grassland/Shrubland

Agriculture

Wetland

Nonmechanically disturbed

EXPLANATION

LAND-USE/LAND-COVER CLASS

Figure 5. Gross change (area gained from, and lost to, other 

land-cover classes) in forest land-cover class in all 17 Midwest–

South Central United States ecoregions over entire study period 

(1973–2000). Colored bars above zero axis indicate land-cover 

classes that lost area to forest and amounts of area lost, whereas 

colored bars below zero axis indicate land-cover classes that 

gained area from forest and amounts of area gained.
12 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Figure 6. Agricultural areas in Midwest–South Central United 

States. Nearly level land and deep soils produce copious amounts 

of row crops such as corn, in Central Corn Belt Plains Ecoregion 

(A), and cotton, in Mississippi Alluvial Plain Ecoregion (B). Slightly 

rolling topography in Southeastern Wisconsin Till Plains Ecoregion 

(C) is more varied but still highly agricultural. 

A

B

C

 Agriculture Land-Cover Class

Agriculture land cover played a leading role in shaping 

the landscape in the Midwest–South Central United States 

between 1973 and 2000 (figs. 6A,B,C). Although agricultural 

land primarily was being lost to developed land, a small percent of the region’s agricultural land was being converted to 

grassland/shrubland. The primary gain in the agriculture landcover class in the region was caused by forested land being 

cleared for agricultural expansion.

Although the trend of agricultural land losing to developed land (figs. 7A,B) was seen in every time period, the 

greatest amount of this type of change occurred between 1992 

and 2000, possibly owing to the overall population increase of 

major metropolitan areas. The ecoregions whose leading landcover change was agriculture to developed included the Eastern Corn Belt Plains, Central Corn Belt Plains, and North Central Hardwood Forests Ecoregions. The driving force behind 

the increase in developed land in the Eastern Corn Belt Plains 

and Central Corn Belt Plains Ecoregions likely was related to 

the expansion of metropolitan areas such as Indianapolis, Indiana, and Chicago, Illinois. In the Northern Central Hardwood 

Forests Ecoregion, upscale exurban housing became more 

abundant on land that previously was agricultural because 

of growth in and around the Minneapolis–Saint Paul, Minnesota, area. The conversion of agricultural land to developed 

land, seen more commonly in the northern ecoregions of the 

Midwest–South Central United States than in the southern 

ecoregions, was primarily due to the size of the metropolitan 

areas. Large-scale metropolitan areas were fewer south of the 

Saint Louis, Missouri, area, and much of the gain in developed 

land in the southern ecoregions of the Midwest–South Central 

United States was accompanied by a loss in forested land.

Gains in agricultural land primarily resulted from the 

clearing of forests (fig. 8). The forest-to-agriculture conversion was one of the top ten most common conversions in the 

Midwest–South Central United States in each time period. The 

largest gains in agriculture occurred in the South Central Highlands Ecoregions group, an area commonly referred to as “the 

Ozarks.” The ecoregions that gained the most agricultural land 

during the study period include the Ozark Highlands, Ouachita 

Mountains, and Boston Mountains Ecoregions, where cattle, 

poultry, and hog farms were the principal source of agricultural productivity (figs. 9A,B). 

Although the underlying drivers and consequences of 

agricultural land-cover change vary geographically, socioeconomic influences can be considered the principal underpinning for regional change. In the early 1970s, socioeconomic 

influences helped to create a “boom” atmosphere in agriculture. This agriculture boom resulted in the continually increasing values of commodities in ecoregions such as the Arkansas 

Valley Ecoregion (Robert Coats, University of Arkansas, oral 

commun., 2011; see also, Demissie, 1986). Additionally, net 

farm incomes in areas such as in the South Central Highlands 

Ecoregions group increased significantly owing to increased 

domestic prices and also to growth in export markets (Robert 
Land-Cover Trends in the Midwest–South Central United States—1973–2000 13

Coats, University of Arkansas, oral commun., 2011; see also, 

Demissie, 1986). Overall, agricultural expansion early in the 

study period in the Midwest–South Central United States was 

helped primarily by the availability of abundant credit from 

various sources, as well as high inflation rates and low interest 

rates on loans, the latter of which increased greatly by the end 

of the 1970s. Indeed, the greatest amount of area converted 

between 1973 and 1980 was from forest to agriculture.

The agriculture boom was short-lived, and, by 1979, the 

Federal Reserve was adopting changes in monetary policy that 

would have a particularly severe impact on agriculture. In the 

early 1980s, economic conditions began to reverse, and, within 

a few years, farm prices fell, inflation slowed, and the demand 

for agricultural land declined, all while export markets declined 

A

B

Figure 7. Interface between developed and agricultural areas in 

Midwest–South Central United States (agriculture to developed 

land-use/land-cover change). A, Edge of new residential 

subdivision abutting field still in agricultural production, in Central 

Corn Belt Plains Ecoregion. B, Aerial photograph of same area 

as in A, showing juxtaposition of different land-use/land-cover 

classes (both images taken in 2009).

Figure 8. Gross change (area gained from, and lost to, other 

land-cover classes) in agriculture land-cover class in all 17 

Midwest–South Central United States ecoregions over entire study 

period (1973–2000). Colored bars above zero axis indicate landcover classes that lost area to agriculture and amounts of area lost, 

whereas colored bars below zero axis indicate land-cover classes 

that gained area from agriculture and amounts of area gained. 

and problems with farm lenders increased. This combination of 

factors sent asset values plummeting. Nationally, the value of 

farm assets declined about $300billion (30percent) between

1981 and 1987 (Barnett, 2000); however, in some areas such 

as the Midwest–South Central United States, the situation was 

much worse. Land values in the Eastern Corn Belt Plains and 

Central Corn Belt Plains Ecoregions fell by about 50 percent 

in nominal terms (Barnett, 2000). The percentage of land that 

converted to agriculture decreased significantly after the period 

between 1973 and 1980. It was at about this time that the 

Conservation Reserve Program (CRP) took effect. Although 

the agriculture-to-grassland/shrubland conversion was not a 

significant story in the larger Midwest–South Central United 

States region, effects of both the CRP and overall farmland 

1973–1980 1980–1986 1986–1992 1992–2000

8

6

4

2

0

–2

–4

–6

–8

Area changed, in thousands of square kilometers

EXPLANATION

LAND-USE/LAND-COVER CLASS

Time period

Water

Developed

Mechanically disturbed

Mining

Barren

Forest

Grassland/Shrubland

Wetland
14 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

abandonment are evident in certain ecoregions such as the Eastern Corn Belt Plains and Ozark Highlands Ecoregions. 

As the rates of conversion from forest to agriculture 

slowed, the rates of agriculture-to-developed conversion began 

to increase. The socioeconomic implications of the conversion 

from agricultural land to developed land vary from ecoregion 

to ecoregion, but, overall, land values for developed land uses 

typically exceed those for rural land uses (Alig and others, 

2004). For many landowners, the trend toward increased 

development potentially can increase their net worth, allowing 

them to either borrow more to expand their operations or sell 

their land for capital gains (Alig and others, 2004). Development nearby also can provide off-farm job opportunities that, 

for the average farm household, mean earning more away from 

the farm than on it (Ahearn and others, 1993; Alig and others, 

2004). As with any socioeconomic driver, however, the loss of 

agricultural land to developed land can alter ecosystems’ characteristics such as water quality and wildlife habitat, as well as 

affect farm sustainability (see, for example, Brown and others, 

2009; U.S. Environmental Protection Agency, 2011). 

Figure 9. Agricultural areas in South Central Highlands 

Ecoregions group. A, Poultry barns (confined-animal-feeding 

operations) on edge of forest in Boston Mountains Ecoregion. B, 

Cattle grazing on pastureland next to wooded area in Ouachita 

Mountains Ecoregion.

A

B

Developed Land-Cover Class

The developed land-cover class consists of built-up 

land and also its supporting infrastructure, which includes 

roads, transmission lines, power-generating facilities, and 

water-treatment plants (figs. 10A,B,C,D). Highly maintained 

recreational lands such as athletic fields, parks, golf courses, 

and ski resorts also are included in the developed landcover class. At the beginning of the study period (1973), 

developed lands covered about 3.6 percent of the Midwest–

South Central United States region. By 2000, an estimated 

5.1 percent of the region was developed, an increase of 42 

percent. The largest per-period increase (13 percent) occurred 

between 1992 and 2000, which was a time of substantial 

residential expansion (von Hoffmann, 1999). In each period, 

most newly developed land converted from farmland; the 

remaining developed land converted from forested land 

(fig. 11). Once development has taken place, nearly all land 

remains in a built-up or developed state. 

Development in the Midwest–South Central United 

States region occurred primarily by the expansion of existing 

metropolitan areas, and increased suburban and exurban 

growth resulted in a larger urban footprint for the region 

during the study period. Exurban areas are areas near the 

fringe of a large urban area that have low density and high 

population growth; at least 20 percent of their residents 

commute to an urbanized area, and at least 20 percent of 

their residents live outside of municipal boundaries (Berube 

and others, 2006). The Midwest–South Central United States 

region also was characterized, however, by the growth of 

urban centers or micropolitan areas (that is, areas that have 

populations of at least 10,000 but less than 50,000), which 

function independently of metropolitan areas. 

The largest (by a considerable amount) increase in 

developed land occurred in Midwest–South Central United 

States ecoregions that are predominately agricultural but 

also include large commercial and industrial cities. As would 

be expected, among the most common conversions in these 

ecoregions was from farmland to developed land, and this 

was the fifth most common conversion in the Midwest–South 

Central United States during the 27-year study period (1973–

2000). These conversions took place mostly on agricultural 

land near the fringes of existing metropolitan areas, in the 

form of medium- or low-density residential and commercial 

development. Notable examples include metropolitan 

Chicago, Illinois; Minneapolis and Saint Paul, Minnesota; 

Detroit, Michigan; Indianapolis, Indiana; Columbus, Ohio; 

and Saint Louis, Missouri. In each of these metropolitan areas, 

many suburban and exurban counties grew at rates that range 

from about 30 to over 200 percent during the 27-year study 

period. In the Central Corn Belt Plains Ecoregion, which 

had among the largest amounts of land that converted from 

agriculture to developed, three of Chicago’s suburban counties 

had population increases of greater than 100percent between 

1970 and 2000 (U.S. Census Bureau, 1970–2000 [various 

years]). The two central counties of the Minneapolis–Saint 
Land-Cover Trends in the Midwest–South Central United States—1973–2000 15

Paul metropolitan region, located within the North Central 

Hardwood Forests Ecoregion, were ringed by eight counties 

that had population increases of 93 to 251 percent. The Saint 

Louis area, in the Interior River Lowland Ecoregion, had one 

suburban county and two exurban counties that grew by 116 

to 205 percent between 1970 and 2000 (U.S. Census Bureau, 

1970–2000 [various years]). In each of these expanding 

metropolitan areas, lower density settlement patterns have 

resulted in a greater amount of developed land per capita in 

outlying areas as compared to central cities. 

Some of the more recent development in the Midwest–

South Central United States has occurred in exurban counties. 

For example, Livingston County, Michigan, which is within 

commuting distance of Detroit, Lansing, and Ann Arbor, 

Michigan, increased in population by 35.7 percent between 

1990 and 2000, and it increased by 166.2 percent between 

1970 and 2000 (U.S. Census Bureau, 1970–2000 [various 

years]). Saint Tammany Parish, Louisiana, located on the north 

shore of Lake Pontchartrain across from New Orleans, Louisiana, grew by 32.3 percent between 1990 and 2000 and by 

200.8percent during the entire 27-year study period. Residents 

of exurban areas are attracted to the amenities of rural living, 

Figure 10. Developed areas in Midwest–South Central United States. A, New, large-scale residential area and golf course on north 

side of Cincinnati, Ohio, metropolitan area, in Eastern Corn Belt Plains Ecoregion. B, Manufacturing plant on outskirts of Lafayette, 

Louisiana, in Mississippi Alluvial Plain Ecoregion. C, World headquarters of major automobile-manufacturing corporation, in Southern 

Michigan/Northern Indiana Drift Plains Ecoregion. D, Boat launch and parking area, in Northern Minnesota Wetlands Ecoregion.

and their communities are characterized by low-density housing that often is intermingled with farmland, forest, water, and 

wetlands. More land per capita is converted to developed land 

cover in exurban areas because their density of development is 

substantially lower than that of suburban areas. 

At the same time that suburban and exurban areas were 

growing in population and construction of transportation infrastructure, housing, schools, hospitals, and commercial establishments were increasing to accommodate that growth, many 

central cities were losing population. For example, Saint Louis 

lost 44 percent of its population during the 27-year study 

period, and Cleveland, Detroit, and Chicago lost 36 percent, 

32 percent, and 14 percent, respectively. In some instances, 

the large-scale loss of population signaled the decline or disappearance of churches, schools, retail establishments, and viable neighborhoods, as well as substantial losses to the tax base. 

Development in the Midwest–South Central United 

States did not always occur only in or near large metropolitan 

areas but, rather, also took place in micropolitan areas and 

adjacent counties, which are socially and economically integrated with large urban cores (U.S. Office of Management 

and Budget, 2003). By 2003, about 10.3 percent of the United 

B

D

A

C
16 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

States population lived in micropolitan areas, whereas about 

83.0 percent resided in metropolitan areas (Mackun, 2005). 

The largest micropolitan areas were generally the fastest 

growing, as indicated by the percentage of population change 

between 1990 and 2000 (Mackun, 2005). Among the most rapidly growing micropolitan areas in the Midwest–South Central 

United States was the Traverse City, Michigan, area, which is 

located in the Northern Lakes and Forests Ecoregion. Traverse 

City had a 23.3 percent increase in population between 1990 

and 2000, and it also experienced large increases throughout 

the entire 27-year study period, owing to the demand for resort 

and second-home development. Other high-growth micropolitan areas include Brainerd, Minnesota, also within the Northern Lakes and Forests Ecoregion, and Branson, Missouri, in 

the Ozark Highlands Ecoregion.

1973–1980 1980–1986 1986–1992 1992–2000

8

7

6

5

4

3

2

1

0

Area changed, in thousands of square kilometers

Time period

EXPLANATION

LAND-USE/LAND-COVER CLASS

Water

Mechanically disturbed

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Figure 11. Estimated area gained in developed land-cover class 

from other land-cover classes in all 17 Midwest–South Central 

United States ecoregions over entire study period (1973–2000). 

Colored bars indicate land-cover classes that lost area to 

developed and amounts of area lost.

Transitional Land-Cover Classes

The transitional land-cover classes—mechanically 

disturbed, nonmechanically disturbed, and, to some degree, 

grassland/shrubland—represent transitional stages of landcover/land-use change in the Midwest–South Central United 

States. During the 27-year study period, the mechanically 

disturbed and nonmechanically disturbed land-cover classes 

almost never persisted longer than one time period; however, 

agriculture or forest that converted to grassland/shrubland 

before converting to (usually) forest may have persisted 

in several time periods. Transitional land-cover classes, 

although the least extensive in areal percentage at any one 

time, cumulatively had a substantial effect on land change, 

especially land-cover change, in the Midwest–South Central 

United States.

Although the mechanically disturbed land-cover class 

never accounted for more than two percent of the Midwest–

South Central United States region at any one time (table1),

the conversion of forest to mechanically disturbed was the 

leading type of change, affecting 62,212 km2; however, 

some areas were cut twice during the 27-year study period, 

and, thus, the actual amount of land that was harvested 

was smaller. The amount of mechanically disturbed land 

as a percentage of land-cover composition grew over time, 

the last three study dates (1986, 1992, 2000) having more 

than the first two (1973, 1980). The areal percentage of 

mechanically disturbed land in 2000 was more than twice as 

much as that in 1973 (table 1).

Land that has been mechanically disturbed by wood 

harvesting could either regenerate directly back to forest 

by the next time period, or it could experience a slower 

regeneration, converting to grassland/shrubland before 

being classified as forest again. The latter is illustrated by 

the conversion from mechanically disturbed to grassland/

shrubland, the fourth leading type of change in the Midwest–

South Central United States, at an estimated 14,577 km2. 

Agricultural deintensification, farmland abandonment, or 

land idled for more than one season was another source 

of the transitory or semitransitory grassland/shrubland 

land-cover class (land enrolled in the Conservation 

Reserve Program could be considered semitransitory). The 

conversion from agriculture to grassland/shrubland affected 

an estimated 5,187 km2, primarily in the Ozark Highlands, 

South Central Plains, North Central Hardwood Forests, and 

Eastern Corn Belt Plains Ecoregions. 

The least common transitional land-cover class in the 

Midwest–South Central United States was nonmechanically 

disturbed. This land-cover class records forest mortality 

caused by wildfire, storm damage, or insect devastation. 

During the 27-year study period, fire likely was the most 

common cause of this rather infrequent conversion. This 

type of change was detected primarily in the Northern Lakes 

and Forests Ecoregion, where certain forest-management 

practices on public lands took place (for example, allowing 

wildfires to occur in designated wilderness areas; Drobyshev 
Land-Cover Trends in the Midwest–South Central United States—1973–2000 17

and others, 2008). Although low-intensity burning is a 

common forest-management practice in the southern parts of 

the Midwest–South Central United States, it typically does 

not cause stand-replacing land-cover change and, thus, is not 

easily detected using this study’s methodology. 

Transitional land-cover classes, although small in 

regional extent at any one time, usually affect substantial 

amounts of area in particular ecoregions, especially those 

intensively involved with forestry land use. The physical 

environmental conditions—for example, surface albedo 

and surface roughness (Barnes and Roy, 2010), erosion and 

sedimentation, and biomass—of these transitional landcover classes also are potentially altered. Environmental 

impacts that stem from these changing conditions potentially 

could include adverse effects on water quality and quantity, 

carbon sources and sinks, wildlife habitat, and biodiversity 

(Loveland and Acevedo, 2006). 

Wetland Land-Cover Class

The wetland land-cover class was the third largest (following agriculture and forest) in the Midwest–South Central 

United States throughout the study period. The variation in 

characteristics of wetlands in the region are considerable, ranging from the coastal wetlands and bottomland hardwood forests 

of the Mississippi Alluvial Plain Ecoregion (and other southern 

ecoregions) to the inland wetlands such as peatlands in the 

northern ecoregions of Minnesota, Wisconsin, and Michigan 

(primarily in the Northern Lakes and Forests Ecoregion). And, 

although the overall change in the wetland land-cover class 

was small (an estimated 0.4 percent change, from 8.9 percent 

in 1973 to 8.5 percent in 2000), change in wetlands is arguably 

one of the most environmentally and socioeconomically concerning issues in regards to groundwater supply, water quality, 

floodwater storage, shoreline erosion, and climate change. Two 

major federal policies designed to protect wetlands—the Wetland Conservation Provisions (also known as “Swampbuster”), 

which was authorized in the 1985 Farm Bill, and the Wetlands 

Reserve Program, which was authorized in 1990 (U.S. Department of Agriculture, Natural Resources Conservation Service, 

2015)—were initiated during the study period. Although these 

policies may not have played a large role in wetland gains in 

the entire Midwest–South Central United States, they likely 

played a significant role in individual ecoregions.

Wetland loss in the Midwest–South Central United 

States was related principally to conversions to water and, 

secondarily, to conversions to agriculture. Both coastal and 

inland wetland areas were affected by human and natural 

processes. Human-induced changes in coastal wetlands 

included building of levees on the Mississippi River, canal 

dredging, draining of wetlands for agriculture, and modifying drainage patterns, as well as sediment erosion and land 

subsidence, whereas inland wetlands were affected primarily 

by ditching and tile draining (U.S. Department of the Interior, 1994; Williams and Cichon, 1994; Prince, 1997; Caffey 

and Schexnayder, 2003; Morton and others, 2003). Natural 

variations in wetland extent in the Midwest–South Central 

United States were the result of sea-level rise, storms, and, 

to a lesser extent, wetter climatic conditions (Williams and 

Cichon, 1994). 

Most of the wetland-to-water conversion occurred in 

the Mississippi Alluvial Plain Ecoregion where an estimated 

4,367 km2 of wetland loss (much of it coastal marsh) 

translated to a 2.6 percent increase in the water land-cover 

class (figs. 12A,B). Most of the wetland loss took place in the 

first time period (1973–1980; table 5), reinforcing the findings 

of Couvillion and others (2011) that, between 1973 and 2000, 

coastal-wetland loss in Louisiana was greatest between 1973 

and 1985. In the northern wetlands, one of the historically 

most important land-cover changes was the conversion of 

Figure 12. False-color Landsat satellite images of part of lower 

Mississippi River delta, in Mississippi Alluvial Plain Ecoregion, 

illustrating loss of wetlands between 1973 (A) and 2001 (B). 

Mosaic of coastal marsh (dark red areas) and open water can be 

seen in lower half of 1973 image (A). By 2001 (B), most wetland 

areas have been replaced by open water. Sources of imagery: 

1973, Landsat Multispectral Scanner; 2001, Landsat Enhanced 

Thematic Mapper.

A B
18 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

wetlands to agricultural land (Prince, 1997), accomplished by 

ditching and tile draining. These practices were most active 

in the northern ecoregions of the Midwest–South Central 

United States between 1870 and 1920 and also between 1950 

and 1980 (Prince, 1997); however, draining for agricultural 

expansion also was common in the southern wetland areas, 

primarily in the Mississippi Alluvial Plain Ecoregion. In 

the Midwest–South Central United States overall, these 

practices were generally curtailed in the 1980s owing to 

both the national farm crisis and the introduction of certain 

agroenvironmental policies, as indicated by a decline in the 

amount of land that converted from wetland to agriculture in 

the time periods after 1986 (1986–1992, 1992–2000). 

Although gains in the wetland land-cover class were not 

prevalent in the Midwest–South Central United States, these 

types of land-cover conversions did occur, and they may have 

been a result of drivers such as changes in both climate and 

domestic policies. For example, whereas the water-to-wetland 

land-cover change may have been related to interannual 

weather fluctuations, gains in wetlands from agricultural 

land may have been related to the Wetland Conservation 

Provisions and the Wetlands Reserve Program. The Wetland 

Conservation Provisions prohibit program participants from 

converting remaining wetland areas on their agricultural 

land to cropland or pastureland unless the amount of wetland 

area is compensated through wetland mitigation (U.S. 

Department of Agriculture, Natural Resources Conservation 

Service, 2015). The Wetlands Reserve Program is a voluntary 

program that offered landowners the opportunity to protect, 

restore, and enhance wetland areas on their property. (Note 

that the current [2015] federal farm bill has replaced the 

Wetland Reserve Program with Wetland Reserve Easements, 

although the overall policy has not changed; U.S. Department 

of Agriculture, Natural Resources Conservation Service, 

2015.) Wetland had the greatest net gain from agriculture 

(an estimated 236 km2) between 1992 and 2000 when both 

of these programs had been fully implemented, although 

probably not all of the agriculture-to-wetland conversion was 

the result of these polices.

Water Land-Cover Class

The water land-cover class, which accounted for an estimated 5.6 percent of the Midwest–South Central United States 

in 2000, was relatively stable during the study period, experiencing only a slight increase (0.4 percent). The Midwest–

South Central United States region contains some of the largest river systems in the nation, including the Mississippi, the 

lower Missouri, and the Illinois Rivers. The most significant 

changes that affected the water land-cover class were associated with the wetland and, to a much lesser extent, agriculture 

land-cover classes.

The loss of water to wetland, the most common conversion for the water land-cover class, occurred primarily in the 

Mississippi Alluvial Plain Ecoregion. This type of conversion 

also took place in the Northern Lakes and Forests Ecoregion 

where 661 km2 of water changed to wetland, likely the result 

of the natural succession of emergent wetland communities, as 

well as interannual weather fluctuations.

Although the Mississippi Alluvial Plain Ecoregion lost 

some of its open water to wetlands, it also gained open water 

from wetlands; however, the area that converted from wetland 

to water was much more substantial than that of water to 

wetland. Gains in water may be chiefly related to natural 

fluctuations of, and changes in, climate and precipitation. 

Small gains in water that came from agriculture may be traced 

to the creation of catfish (predominately the channel catfish, 

Ictalurus punctatus) farm ponds, mainly in the Mississippi 

Alluvial Plain Ecoregion (note that catfish ponds were mapped 

as the water land-cover class, whereas seasonally inundated 

rice fields were not). 

Grassland/Shrubland Land-Cover Class

The grassland/shrubland land-cover class accounted for 

about 1.3 percent of the Midwest–South Central United States 

in 2000. Regionally, no significant gain or loss of grassland/

shrubland occurred during the study period; most of the 

changes in grassland/shrubland are associated with forestmanagement methods practiced in the region. The amount 

increased slightly between 1980 (1.2 percent) and 1992 (1.5 

percent), which may be a reflection of agricultural-land abandonment owing to both the agroeconomic crisis of the 1980s 

and implementation of the Conservation Reserve Program. 

Other than changes in grassland/shrubland caused by the 

timber industry, the loss of grassland/shrubland may best be 

associated with small gains in agriculture; however, this type 

of conversion was not a leading land-cover change during the 

study period. The small percentage of grassland/shrubland that 

converted to agriculture was chiefly in the Ozark Highlands 

Ecoregion, and it may be the result of increases in cattle and 

poultry production, which also includes increased haying, 

more intense use of pasturelands, and (or) the building of 

structures for confined-animal-feeding operations. 

Gains in grassland/shrubland, which did not have a large 

impact on the Midwest–South Central United States, were 

chiefly related to losses in agriculture; the largest such gains 

were seen in the Ozark Highlands, South Central Plains, and 

Mississippi Alluvial Plain Ecoregions. And, although the 

gains were smaller, this type of conversion also was common in the North Central Hardwood Forests Ecoregion and in 

the Southeastern Wisconsin Till Plains Ecoregion. Although 

the CRP played less of a role in the Midwest–South Central 

United States than it did in the Great Plains, it can explain 

some of the conversions from agricultural land to grassland/

shrubland seen later in the study period. For example, the 

CRP may explain the increase of grassland/shrubland seen 

in the Driftless Area Ecoregion between 1986 and 1992; 

however, farmland abandonment and changes in agricultural 

production patterns caused by the farm crisis of the 1980s 

may have been a larger contributing factor in gains seen in 

grassland/shrubland.
Land-Cover Trends in the Midwest–South Central United States—1973–2000 19

Mining Land-Cover Class

Mining made up only 0.1 percent of the Midwest–South 

Central United States at the beginning of the study period 

(1973). By 2000, the areal percentage in mining had doubled, 

although it still remained among the least extensive land-cover 

classes. The South Central Plains and Arkansas Valley Ecoregions both contain areas of petroleum and natural-gas production. Increases in oil and gas extraction accounted for most of 

the gains in mining during the study period (fig.13), despite

the fact that the processing (refining plants) and distribution 

(storage) of hydrocarbon products are mapped as developed. 

Aggregate mining was common in several ecoregions that experienced increased urbanization within the northern parts of the 

Midwest–South Central United States (for example, the Eastern 

Corn Belt Plains, Central Corn Belt Plains, Southeastern Wisconsin Till Plains, Southern Michigan/Northern Indiana Drift 

Plains, and Erie Drift Plains Ecoregions). Significant iron-ore 

production characterized mining in the Northern Lakes and Forests Ecoregion. Although critical to energy production, manufacturing, and urban growth, mining made up a minimal amount 

of land area in the Midwest–South Central United States.

Barren Land-Cover Class

Barren land made up the smallest land-cover class in the 

Midwest–South Central United States during the study period, 

accounting for a mere 0.03 percent in 2000. Regionally, no 

significant gains or losses of barren land occurred during the 

study period, and only minor fluctuations took place between 

the barren land-cover class and the water and wetland landcover classes. Such changes likely were due to natural fluctuations in the region’s climate and precipitation regimes, especially along large river channels where substantial changes in 

sand bars could often be mapped. 

Summary

Land-use/land-cover changes can impact a region in various ways, including water quality and quantity, wildlife habitat 

change, land-atmosphere interactions, and changes in carbon 

stocks and cycles. Land change in the Midwest–South Central 

United States during the study period was chiefly related to 

forest harvesting and also to increased urbanization, as well as, 

to a much lesser extent, to wetland loss owing to agricultural 

expansion in some ecoregions. Intensive and areally substantial 

forest-management practices led to periodic changes in forest 

land cover in a number of ecoregions. Increases in developed 

land usually occurred in the suburban and exurban periphery 

of already established urban areas, which are concentrated 

heavily in the industrial parts of the Midwest–South Central 

United States region. Although the agriculture land-cover class 

decreased slightly overall in the Midwest–South Central United 

States region, geographic variability in the agriculture landcover class was more evident at the ecoregional scale. Early in 

the study period, southern wetland losses mostly were because 

of land-use change (for example, the conversion of forested 

wetlands to agricultural land or the cutting of ship channels 

through coastal marshland to support oil and natural gas extraction, both of which took place in the Mississippi Alluvial Plain 

Ecoregion), whereas northern wetlands were affected more by 

climate variability (interannual weather fluctuations), mainly 

during the second half of the study period. Although small in 

overall regional extent at any one time, the transitional landcover classes (mainly mechanically disturbed and nonmechanically disturbed) provided much of the overall land-cover 

change in the Midwest–South Central United States. 

The stories of land-use/land-cover change and its impact 

in the Midwest–South Central United States can be better 

understood at a finer geographical scale. The change of focus 

from the much larger Midwest–South Central United States 

region to smaller, more homogenous ecoregions allows specific stories of land-use/land-cover change to emerge. The 

remaining chapters in this report, which contain summaries 

of change for each of the 17 individual Midwest–South Central United States ecoregions, document the rates, types, and 

drivers of late-20th century land-use/land-cover change in the 

Midwest–South Central United States. 

References Cited

Ahearn, M.C., Perry J.E., and El-Osta, H.S., 1993, The economic well-being of farm operator households, 1988-1990: 

U.S. Department of Agriculture, Economic Research Service 

Agricultural Economic Report no. 666, 175 p., available at 

http://naldc.nal.usda.gov/download/CAT93990859/PDF. 

Alig, R.J., Kline, J.D., and Lichtenstein, M., 2004, Urbanization on the U.S. landscape—Looking ahead in the 21st 

century: Landscape and Urban Planning, v. 69, p. 219–234.

Figure 13. Natural-gas extraction site in northwestern Louisiana, 

in South Central Plains Ecoregion. These gas wells typically were 

one-half hectare to slightly more than one hectare (one to three 

acres) of mostly open space, needed for movement of equipment 

around well head and for pipeline infrastructure.
20 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Anderson, J.R., Hardy, E.E., Roach, J.T., and Witmer, R.E., 

1976, A land use and land cover classification system for 

use with remote sensor data: U.S. Geological Survey Professional Paper 964, 41 p.

Auch, R.F., Acevedo W., and Taylor, J.L., 2006, The historical development of the nation’s urban areas, in Acevedo, 

W., Taylor, J.L., Hester, D.J., Mladinich, C.S., and Glavac, 

S., eds., Rates, trends, causes, and consequences of urban 

land-use change in the United States: U.S. Geological Survey Professional Paper 1726, p. 1–12, available at http://

pubs.usgs.gov/pp/pp1726/. 

Auch, R.F., Drummond, M.A., Sayler, K.L., Gallant, A.L., 

and Acevedo, W., 2012, An approach to assess land cover 

trends in the conterminous United States (1973-2000), in

Giri, C., ed., Remote sensing of land cover—Principles 

and applications: Boca Raton, Fla., CRC Press, p. 351–

367.

Barnes, C.A., and Roy, D.P., 2010, Radiative forcing over 

the conterminous United States due to contemporary land 

cover land use change and sensitivity to snow and interannual albedo variability: Journal of Geophysical Research, 

v. 115, no. G04033, 14 p., doi:10.1029/2010JG001428.

Barnett, B.J., 2000, The U.S. farm crisis of the 1980s: Agricultural History, v. 74, no. 2, p. 336–380, accessed June 

22, 2011, at http://www.jstor.org/stable/3744858.

Bentley, J.W., Johnson, T.G., and Howell, M., 2002, Arkansas’ timber industry—An assessment of timber product 

output and use, 1999: U.S. Department of Agriculture, 

Forest Service, Southern Research Station, Resource Bulletin SRS79, 40 p., available at http://www.srs.fs.usda.gov/

pubs/5261.

Berube, A., Singer, A., Wilson, J.H., and Frey, W.H., 2006, 

Finding exurbia—America’s fast-growing communities at 

the metropolitan fringe: The Brookings Institution, Metropolitan Policy Program, 48 p., accessed August 30, 2011, 

at http://www.brookings.edu/~/media/Files/rc/reports/2006

/10metropolitanpolicy_berube/20061017_exurbia.pdf. 

Brown, L.R., Cuffney, T.F., Coles, J.F., Fitzpatrick, F., 

McMahon, G., Steuer, J., Bell, A.H., and May, J.T., 2009, 

Urban streams across the USA—Lessons learned from 

studies in 9 metropolitan areas: Journal of the North American Benthological Society, v. 28, no. 4, p. 1,051–1,069.

Caffey, R.H., and Schexnayder, M., eds., 2003, Coastal 

Louisiana and South Florida—A comparative wetland 

inventory: National Sea Grant Library, Interpretive Topic 

Series on Coastal Wetland Restoration in Louisiana, 8 p., 

accessed May 21, 2009, at http://www.lacoast.gov/reports/

its/Florida.pdf.

Couvillion, B.R., Barras, J.A., Steyer, G.D., Sleavin, W., 

Fischer, M., Beck, H., Trahan, N., Griffin, B., and Heckman, 

D., 2011, Land area change in coastal Louisiana from 1932 

to 2010: U.S. Geological Survey Scientific Investigations 

Map 3164, scale 1:265,000, pamphlet 12 p., available at 

http://pubs.usgs.gov/sim/3164/.

Demissie, E., 1986, Farm financial trend in Missouri and its 

future implications: Agriculture and Human Values, v. 3, 

no. 4, p. 66–74.

Drobyshev, I., Goebol, P.C., Hix, D.M., Corace, R.G., III, and 

Semko-Duncan, M.E., 2008, Pre- and post-European settlement fire history of red pine dominated forest ecosystems of 

Seney National Wildlife Refuge, upper Michigan: Canadian 

Journal of Forest Resources, v. 38, p. 2,497–2,514. 

Lamb, F.M., 1967, Aspen wood characteristics, properties, 

and uses—A review of recent literature: U.S. Department of 

Agriculture, Forest Service, North Central Forest Experiment Station, Research Paper NC-13, available at http://

www.treesearch.fs.fed.us/pubs/10534.

Loveland, T.R., and Acevedo, W., 2006, Land cover change in 

the eastern United States: U.S. Geological Survey Web site, 

accessed July 28, 2011, at http://landcovertrends.usgs.gov/

east/regionalSummary.html.

Loveland, T.R., Sohl, T.L., Stehman, S.V., Gallant, A.L., 

Sayler, K.L., and Napton, D.E., 2002, A strategy for 

estimating the rates of recent United States land cover 

changes: Photogrammetric Engineering & Remote Sensing, 

v. 68, no. 10, p. 1,091–1,099.

Mackun, P.J., 2005, Population change in metropolitan and 

micropolitan statistical areas—1990–2003: U.S. Census 

Bureau database, accessed August 30, 2011, at http://www.

census.gov/prod/2005pubs/p25-1134.pdf.

Morton, R.A., Tiling, G., and Ferina, N.F., 2003, Causes of 

hot-spot wetland loss in the Mississippi delta plain: Environmental Geosciences, v. 10, no. 2, p. 71–80.

Prince, H., 1997, Wetlands of the American Midwest—A historical geography of changing attitudes: Chicago, Ill., The 

University of Chicago Press, 395 p.

Reading, W.H., IV, and Krantz, J., 2002, Minnesota timber 

industry—An assessment of timber product output and 

use, 1997: U.S. Department of Agriculture, Forest Service, 

North Central Research Station, Resource Bulletin NC-204, 

71 p., available at http://www.nrs.fs.fed.us/pubs/1434.

Sohl, T.L., Gallant, A.L., and Loveland, T.R., 2004, The characteristics and interpretability of land surface change and 

implications for project design: Photogrammetric Engineering & Remote Sensing, v. 70, no. 4, p. 439–448.
Land-Cover Trends in the Midwest–South Central United States—1973–2000 21

Stehman, S.V., Sohl, T.L., and Loveland, T.R., 2003, Statistical 

sampling to characterize recent United States land-cover change: 

Remote Sensing of Environment, v. 86, no. 4, p. 517–529.

Structural Board Association, 1999, OSB and the environment: Structural Board Association, Technical Bulletin 118, 

accessed August 16, 2011, at http://osbguide.tecotested.com/

pdfs/en/tb118.pdf.

U.S. Census Bureau, 1970–2000 [various years], Census of 

population and housing: U.S. Census Bureau database, 

accessed April 29, 2015, at http://www.census.gov/prod/

www/decennial.html.

U.S. Department of Agriculture, Natural Resources Conservation Service, 2015, Wetlands: U.S. Department of Agriculture, Natural Resources Conservation Service database, 

accessed May 1, 2015, at http://www.nrcs.usda.gov/wps/

portal/nrcs/main/national/water/wetlands/.

U.S. Department of the Interior, 1994, The impact of Federal 

programs on wetlands, vol. II—The Everglades, coastal 

Louisiana, Galveston Bay, Puerto Rico, California’s Central 

Valley, western riparian areas, southeastern and western 

Alaska, the Delmarva Peninsula, North Carolina, northeastern New Jersey, Michigan, and Nebraska: U.S. Department 

of the Interior database, accessed January 22, 2013, at http://

www.doi.gov/pmb/oepc/wetlands2/index.cfm.

U.S. Environmental Protection Agency, 1999, Level III ecoregions of the continental United States: U.S. Environmental 

Protection Agency National Health and Environmental Effects 

Research Laboratory, scale 1:7,500,000, available at ftp://ftp.

epa.gov/wed/ecoregions/usgs/useco_March1999_v5.pdf.

U.S. Environmental Protection Agency, 2010, North American terrestrial ecoregions—Level III: U.S. Environmental 

Protection Agency database, accessed April 29, 2015, 

at http://www.epa.gov/wed/pages/ecoregions/na_eco.

htm#Downloads.

U.S. Environmental Protection Agency, 2011, Urbanization and streams—Studies of hydrologic impacts: U.S. 

Environmental Protection Agency database, accessed 

November 23, 2011, at http://water.epa.gov/polwaste/nps/

urban/report.cfm.

U.S. Office of Management and Budget, 2003, Metropolitan 

statistical areas, micropolitan statistical areas, combined 

statistical areas, New England city and town areas, and 

combined New England city and town areas—2003: 

U.S. Office of Management and Budget, Statistical 

and Science Policy Branch, Office of Information and 

Regulatory Affairs Bulletin No. 03-04 Attachment, 141 

p., accessed August 30, 2011, at http://www.whitehouse.

gov/sites/default/files/omb/assets/omb/bulletins/b03-

04_attach.pdf. 

Vogelmann, J.E., Howard, S.M., Yang, L., Larson, C.R., 

Wylie, B.K., and van Driel, N., 2001, Completion of the 

1990s National Land Cover Data Set for the conterminous United States from Landsat Thematic Mapper data 

and ancillary data sources: Photogrammetric Engineering 

& Remote Sensing, v. 67, no. 6, p. 650–662.

von Hoffman, A., 1999, Housing heats up—Home building 

patterns in metropolitan areas: The Brookings Institution, 

Center on Urban & Metropolitan Policy, Survey Series, 

11 p., accessed August 30, 2011, at http://www.brookings.edu/~/media/Files/rc/reports/1999/12metropolitanpol

icy_hoffman/hoffman.pdf. 

Williams, S.J., and Cichon, H.A., eds., 1994, Processes of 

coastal wetlands loss in Louisiana—Results from a multiyear collaborative study by the U.S. Geological Survey, 

National Biological Survey, and Louisiana State University: U.S. Geological Survey Open-File Report 94–275, 

226 p., available at http://pubs.usgs.gov/of/1994/0275/

report.pdf.

Northern Forests Ecoregions

Chapter 1

Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000 

Edited by Roger F. Auch and Krista A. Karstensen 

U.S. Geological Survey Professional Paper 1794–C, 2015

Northern Minnesota Wetlands Ecoregion

By Kristi L. Sayler

Ecoregion Description 

The Northern Minnesota Wetlands Ecoregion is a relatively 

small ecoregion that covers about 24,427 km2 (9,431 mi2) of 

northern Minnesota along the Canadian border (fig. 1) (Omernik, 

1987; Wiken and others, 2011). The ecoregion is bounded by the 

Northern Lakes and Forests, North Central Hardwood Forests, 

and Lake Agassiz Plain Ecoregions. The Northern Minnesota 

Wetlands Ecoregion has a considerable amount of federal, 

state, and tribal lands in the form of national parks, forests, and 

wildlife refuges, state forest and game production areas, and 

Indian reservations. The ecoregion is composed mostly of level 

marshlands covered by swamp and boreal-forest vegetation. At 

one time this region was covered by broad glacial lakes, and 

much of the ecoregion is still covered by standing water (Wiken 

and others, 2011). During the process of glacial retreat about 

94° 93°

97° 96° 95°

49°

48°

Lake Agassiz

Plain

Northern

Lakes and Forests North Central

Hardwood Forests

CANADA

0 50 100 MILES

0 50 100 KILOMETERS

Ecoregion boundary

Sample block (10 x 10 km)

Land-use/land-cover class

Water

Developed

Transitional

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Ice/Snow

EXPLANATION

MN

Northern

Minnesota

Wetlands

Ecoregion

MINNESOTA

CANADA

ND

BELTRAMI

COUNTY

KOOCHICHING

COUNTY

Lower

Red Lake

Lake

of the

Woods

LAKE

OF THE

WOODS

COUNTY

Upper Red Lake

International

Falls

RED LAKE

RESERVATION

10 thousand years ago, the high water table that resulted from 

the giant glacial lakes saturated the vegetation and created an 

environment that lacked oxygen, which is needed for aerobic 

decomposition; thus, instead of decomposing completely, 

vegetation accumulated in layers to create the one of the largest 

peatland complexes in North America (Vileisis, 1997). 

The landscape of the Northern Minnesota Wetlands 

Ecoregion is a mosaic of wetlands (fig. 2), water, and forest, 

with scattered agricultural areas. Three large lakes that remain 

from the time of the glaciers are within this ecoregion: Lake 

of the Woods, which covers the northern part of Lake of the 

Woods County in the northern part of the ecoregion, is a 

remnant of Glacial Lake Agassiz (Gustafson, 1997); Upper 

Red Lake and Lower Red Lake, which are in north-central 

Figure 1. Map of Northern Minnesota Wetlands Ecoregion and surrounding 

ecoregions, showing land-use/land-cover classes from 1992 National Land 

Cover Dataset (Vogelmann and others, 2001); note that not all land-use/

land-cover classes shown in explanation may be depicted on map; note 

also that, for this “Status and Trends of Land Change” study, transitional 

land-cover class 

was subdivided into 

mechanically disturbed 

and nonmechanically 

disturbed classes. 

Squares indicate 

locations of 10 x 10 km 

sample blocks analyzed 

in study. Index map 

shows locations of 

geographic features 

mentioned in text. 

Abbreviations for 

Midwest–South Central 

United States ecoregions 

are listed in appendix 2. 

Also shown is part of one 

Great Plains ecoregion, 

Lake Agassiz Plain. See 

appendix 3 for definitions 

of land-use/land-cover 

classifications.
26 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Beltrami County, cover part of the Red Lake Reservation. 

The elevation ranges from 314 to 450 m, with little variation. 

The ecoregion has a severe, humid, midlatitude continental 

climate, marked by warm summers and cold winters. The 

mean annual temperature is about 2°C, with a mean summer 

temperature of 16°C and a mean winter temperature of -12°C 

(Wiken and others, 2011). The mean annual precipitation of 

the ecoregion is 599 mm (24 in.), ranging from 550 to 700 mm 

(22–28 in.), with most of the precipitation falling during the 

summer growing season (Wiken and others, 2011). 

Forestry is an important land use in the Northern 

Minnesota Wetlands Ecoregion. By the late 1800s, most of 

the northern Minnesota forests had been logged, and the state 

was supplying much of the timber needed for building in the 

United States (Borchert, 1959). Today, most of the timber 

harvested in the area is used for pulp and paper mills (fig. 3). 

The Boise Paper mill in International Falls, Minnesota, which 

is the largest city in the ecoregion (population in 2000, 6,703; 

U.S. Census Bureau, 2013), is the city’s largest employer. 

Agriculture is concentrated in the northwestern part of the 

Northern Minnesota Wetlands Ecoregion where wetlands have 

been drained to produce more useable farmland. The major 

0 12 24 36

Area, as percent of ecoregion

Ecoregion 

DA

HELP

CCBP

SMNIDP

NCHF

BM

IRL

SEWTP

OH

EDP

ECBP

NMW

AV

MAP

NLF

SCP

OM

EXPLANATION

Change in one time period

Change in two time periods

Change in three time periods

Change in four time periods

Change in four time periods

Figure 2. Mosaic of wetlands and forest, in Beltrami County, 

Minnesota.

Figure 3. Large forest clearing, in Koochiching County, Minnesota.

Figure 4. Overall spatial change in Northern Minnesota Wetlands 

Ecoregion (NMW; darker bars) compared with that of all 17 

Midwest–South Central United States ecoregions (lighter bars). 

Each horizontal set of bars shows proportions of ecoregion that 

changed during one, two, three, or four time periods; highest level 

of spatial change in Northern Minnesota Wetlands Ecoregion (four 

time periods) labeled for clarity. See table 2 for years covered by 

each time period. See appendix 2 for key to ecoregion abbreviations.

crops are wheat, barley, oats, sunflowers, rye, flax, and corn. 

Some specialty crops, such as wild rice, bluegrass seed, and seed 

potatoes, also are grown. In 2000, the land cover of the ecoregion 

was estimated at about 37 percent forest, 30 percent wetland, 18 

percent agriculture, 12 percent water, and 2 percent or less each 

of grassland/shrubland, mining, and developed. 

Contemporary Land-Cover Change (1973 

to 2000)

The overall spatial change (the percentage of land area that 

changed at least one time) in the Northern Minnesota Wetlands 

Ecoregion between 1973 and 2000 is estimated at 8.2 percent 

(table 1). Compared to the other Midwest–South Central United 

States ecoregions, change in the Northern Minnesota Wetlands 

Ecoregion was moderate to moderately high (fig. 4): an 

estimated 3.4 percent of the ecoregion changed once during the 

study period, and 4.8 percent changed multiple times (table1).

Most areas that changed multiple times showed the different 

stages of land cover as forests were harvested and regrown, 

namely forest, mechanically disturbed, and grassland/shrubland. 

The total change per time period ranged from 2.3 percent of the 

ecoregion between 1973 and 1980 to 4.3 percent between 1992 

and 2000 (table 2). When normalized to account for uneven time 

periods, the period between 1986 and 1992 had the greatest rate 

of change, at 0.7 percent per year (table 2; fig. 5).
Chapter 1—Northern Minnesota Wetlands Ecoregion 27

Figure 6. Normalized average net change in Northern Minnesota 

Wetlands Ecoregion by time period for each land-cover class. 

Bars above zero axis represent net gain, whereas bars below zero 

represent net loss. Note that not all land-cover classes shown 

in explanation may be represented in figure. See appendix 3 for 

definitions of land-use and land-cover classifications.

0.5

0.0

1.0

1.5

2.5

3.0

2.0

3.5

1973 to 1980 1980 to 1986 1986 to 1992 1992 to 2000

Average annual change, as percent of ecoregion

Time period

−2

−1

0

1

2

1973–1980 1980–1986 

Time period

1986–1992 1992–2000 

Area changed, as percent of ecoregion 

Water

Developed

Mechanically disturbed

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Nonmechanically disturbed

Ice/Snow

EXPLANATION

LAND-USE/LAND-COVER CLASS

Figure 5. Estimates of land-cover change per time period, 

normalized to annual rates of change for all 17 Midwest–South 

Central United States ecoregions (gray bars). Estimates of change 

for Northern Minnesota Wetlands Ecoregion are represented by 

red bars in each time period.

The forest, mechanically disturbed, and grassland/

shrubland land-cover classes changed most during the study 

period (table 3). Forest had an estimated net decrease of 

2.1 percent of the ecoregion area (517 km2), a 5.4 percent 

decrease from its 1973 area, with most of the decrease 

occurring as forest converted to mechanically disturbed (fig. 

6). Mechanically disturbed had an estimated net increase 

of 1.0 percent of the ecoregion area (243 km2), a more than 

doubling of the 1973 percentage (fig. 6). Most of the increase 

in mechanically disturbed land was from conversions from 

forested land. 

The most common land-cover conversion for all 

time periods between 1973 and 2000 was from forest to 

mechanically disturbed (table 4). This conversion, as well as 

the others associated with the timber harvest-and-regrowth 

cycle, make up most of the top five land-cover conversions 

and about 75 percent of all the major land-cover changes in 

the Northern Minnesota Wetlands Ecoregion during the study 

period (table 4). 
28 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Table 2. Raw estimates of change in Northern Minnesota Wetlands Ecoregion land cover, computed for 

each of four time periods between 1973 and 2000, and associated error at 85-percent confidence level.

[Estimates of change per period normalized to annual rate of change for each time period]

Period Total change

(% of ecoregion)

Margin of 

error

(+/− %)

Lower 

bound

(%)

Upper bound

(%)

Standard 

error

(%)

Relative 

error

(%)

Average rate

(% per year)

Estimate of change, in percent stratum

1973–1980 2.3 0.9 1.4 3.2 0.6 26.1 0.3

1980–1986 3.4 1.4 2.1 4.8 0.9 27.0 0.6

1986–1992 4.0 1.3 2.7 5.3 0.9 22.1 0.7

1992–2000 4.3 1.3 3.0 5.6 0.9 21.0 0.5

Estimate of change, in square kilometers

1973–1980 556 215 341 770 145 26.1 79

1980–1986 836 335 501 1,170 226 27.0 139

1986–1992 978 320 657 1,298 216 22.1 163

1992–2000 1,047 326 721 1,372 220 21.0 131

Table 1. Percentage of Northern Minnesota Wetlands Ecoregion 

land cover that changed at least one time during study period 

(1973–2000) and associated statistical error.

[Most sample pixels remained unchanged (91.8 percent), whereas 8.2 percent 

changed at least once throughout study period]

Number

of

changes

Percent

of

ecoregion

Margin

of error

(+/− %)

Lower

bound

(%)

Upper

bound

(%)

Standard

error

(%)

Relative

error

(%)

1 3.4 0.7 2.7 4.1 0.5 13.8

2 3.8 1.3 2.4 5.1 0.9 24.0

3 1.0 0.5 0.5 1.4 0.3 33.2

4 0.0 0.0 0.0 0.0 0.0 37.8

Overall 

spatial 

change

8.2 2.3 5.9 10.5 1.6 18.9
Chapter 1—Northern Minnesota Wetlands Ecoregion 29

Table 3. Estimated area (and margin of error) of each land-cover class in Northern Minnesota Wetlands Ecoregion, calculated five 

times between 1973 and 2000. See appendix 3 for definitions of land-cover classifications.

Water Developed

Mechanically 

disturbed

Mining Barren Forest Grassland/

Shrubland Agriculture Wetland

Nonmechanically 

disturbed

% +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/−

Area, in percent stratum

1973 11.6 7.2 0.3 0.2 0.6 0.2 0.0 0.0 0.0 0.0 38.7 6.3 1.2 0.9 17.5 6.5 30.2 6.3 0.0 0.0

1980 11.5 7.1 0.3 0.2 1.2 0.6 0.0 0.0 0.0 0.0 37.7 6.1 1.3 0.8 17.8 6.5 30.1 6.3 0.0 0.0

1986 11.5 7.1 0.3 0.3 1.6 0.7 0.1 0.0 0.0 0.0 36.8 6.0 1.7 0.9 17.9 6.5 30.0 6.3 0.0 0.0

1992 11.6 7.1 0.4 0.3 1.6 0.6 0.1 0.0 0.0 0.0 36.4 6.0 2.0 0.9 18.0 6.5 29.8 6.3 0.0 0.0

2000 11.6 7.1 0.4 0.3 1.6 0.5 0.1 0.0 0.0 0.0 36.6 6.0 1.8 0.9 18.1 6.5 29.9 6.3 0.0 0.0

Net

change 0.0 0.1 0.1 0.1 1.0 0.4 0.0 0.0 0.0 0.0 –2.1 0.6 0.7 0.4 0.5 0.3 –0.3 0.2 0.0 0.0

Gross

change 0.3 0.1 0.1 0.1 3.3 1.1 0.0 0.0 0.0 0.0 4.0 1.2 1.6 0.6 0.8 0.3 1.0 0.3 0.0 0.0

Area, in square kilometers

1973 2,822 1,751 66 52 136 59 9 4 7 9 9,460 1,548 282 210 4,280 1,578 7,367 1,550 0 0

1980 2,815 1,746 74 59 287 152 11 4 7 9 9,219 1,501 325 205 4,342 1,590 7,348 1,547 0 0

1986 2,821 1,745 83 69 382 169 12 5 6 8 8,998 1,458 414 220 4,383 1,593 7,328 1,541 0 0

1992 2,842 1,744 90 76 396 145 16 7 6 8 8,899 1,465 488 217 4,403 1,593 7,286 1,542 0 0

2000 2,832 1,746 92 78 379 130 18 8 5 7 8,943 1,458 452 216 4,411 1,593 7,295 1,540 0 0

Net

change 10 21 26 27 243 103 9 5 –2 2 –517 151 170 87 131 83 –71 57 0 0

Gross

change 80 35 27 27 813 262 11 5 2 2 980 297 402 141 200 83 240 77 0 0
30 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Table 4. Principal land-cover conversions in Northern Minnesota Wetlands Ecoregion, showing amount of area changed (and 

margin of error, calculated at 85-percent confidence level) for each conversion during each of four time periods and also during 

overall study period. See appendix 3 for definitions of land-cover classifications.

[Values given for “other” class are combined totals of values for other land-cover classes not listed in that time period. Abbreviations: n/a, not applicable]

Period From class To class

Area 

changed

Margin of 

error

Standard 

error Percent of 

ecoregion

Percent of all 

changes (km2) (+/− km2) (km2)

1973–1980 Forest Mechanically disturbed 239 149 101 1.0 43.1

Mechanically disturbed Grassland/Shrubland 64 31 21 0.3 11.4

Forest Agriculture 61 30 20 0.2 10.9

Mechanically disturbed Forest 48 25 17 0.2 8.6

Wetland Mechanically disturbed 47 26 18 0.2 8.5

Other Other 98 n/a n/a 0.4 17.5

Totals 556 2.3 100.0

1980–1986 Forest Mechanically disturbed 328 163 110 1.3 39.3

Mechanically disturbed Grassland/Shrubland 124 65 44 0.5 14.9

Mechanically disturbed Forest 123 89 60 0.5 14.8

Forest Agriculture 54 27 18 0.2 6.4

Wetland Mechanically disturbed 52 29 19 0.2 6.2

Other Other 154 n/a n/a 0.6 18.5

Totals 836 3.4 100.0

1986–1992 Forest Mechanically disturbed 329 118 80 1.3 33.7

Mechanically disturbed Forest 179 114 77 0.7 18.3

Mechanically disturbed Grassland/Shrubland 167 74 50 0.7 17.1

Grassland/Shrubland Forest 85 62 42 0.3 8.7

Wetland Mechanically disturbed 65 43 29 0.3 6.6

Other Other 153 n/a n/a 0.6 15.6

Totals 978 4.0 100.0

1992–2000 Forest Mechanically disturbed 308 110 74 1.3 29.5

Mechanically disturbed Forest 221 89 60 0.9 21.1

Grassland/Shrubland Forest 150 65 44 0.6 14.4

Mechanically disturbed Grassland/Shrubland 126 75 50 0.5 12.1

Wetland Mechanically disturbed 68 36 24 0.3 6.5

Other Other 173 n/a n/a 0.7 16.6

Totals 1,047 4.3 100.0

1973–2000

(overall)

Forest Mechanically disturbed 1,205 469 316 4.9 35.3

Mechanically disturbed Forest 571 256 173 2.3 16.7

Mechanically disturbed Grassland/Shrubland 481 220 148 2.0 14.1

Grassland/Shrubland Forest 297 141 95 1.2 8.7

Wetland Mechanically disturbed 231 117 79 0.9 6.8

Other Other 631 n/a n/a 2.6 18.5

Totals 3,416 14.0 100.0
Chapter 1—Northern Minnesota Wetlands Ecoregion 31

References Cited

Borchert, J.R., 1959, Minnesota’s changing geography: 

Minneapolis, University of Minnesota Press, p. 58–63.

Gustafson, T.A., 1997, Soil survey of Lake of the Woods 

County area, Minnesota: U.S. Department of Agriculture, 

Natural Resources Conservation Service, 204 p., available 

at http://soils.usda.gov/survey/online_surveys/minnesota/.

Omernik, J.M., 1987, Ecoregions of the conterminous United 

States: Annals of the Association of American Geographers, 

v. 77, no. 1, p. 118–125.

U.S. Census Bureau, 2013, American fact finder profile of 

general demographic characteristics—2000, International 

Falls, Minnesota: U.S. Census Bureau database, assessed 

April 22, 2013, at http://factfinder2.census.gov/faces/nav/

jsf/pages/index.xhtml.

Vileisis, A., 1997, Discovering the unknown landscape—A 

history of America’s wetlands: Washington, D.C., Island 

Press, 433 p.

Vogelmann, J.E., Howard, S.M., Yang, L., Larson, C.R., 

Wylie, B.K., and van Driel, N., 2001, Completion of the 

1990s National Land Cover Data Set for the conterminous 

United States from Landsat Thematic Mapper data and 

ancillary data sources: Photogrammetric Engineering & 

Remote Sensing, v. 67, p. 650–662.

Wiken, E., Jiménez Nava, F., and Griffith, G., 2011, North 

American terrestrial ecoregions—Level III: Montreal, 

Canada, Commission for Environmental Cooperation, 149 

p., accessed November 5, 2012, at http://www.cec.org/

Storage/133/15860_QA07.30-32_NP_NA_Terrestrial_

Ecoregions_Level_3_Final-2june11.pdf.

Chapter 2

Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000 

Edited by Roger F. Auch and Krista A. Karstensen 

U.S. Geological Survey Professional Paper 1794–C, 2015

Northern Lakes and Forests Ecoregion

By Tamara S. Wilson and Christy L. Ryan

Figure 1. Map of Northern Lakes and Forests Ecoregion and surrounding ecoregions, showing land-use/land-cover classes from 1992 

National Land Cover Dataset (Vogelmann and others, 2001); note that not all land-use/land-cover classes shown in explanation may 

be depicted on map; note also that, for this “Status and Trends of Land Change” study, transitional land-cover class was subdivided 

into mechanically disturbed and nonmechanically disturbed classes. Squares indicate locations of 10 x 10 km sample blocks analyzed 

in study. Index map shows locations of geographic features mentioned in text. Abbreviations for Midwest–South Central United 

States ecoregions are listed in appendix 2. Also shown are parts of three Great Plains ecoregions: Lake Agassiz Plain (LAP), Northern 

Glaciated Plains (NGP), and Western Corn Belt Plains. See appendix 3 for definitions of land-use/land-cover classifications.

88° 86° 84°

94° 92° 90° 88°

48°

46°

44° Driftless Area

Western

Corn Belt

Plains

North Central

Hardwood Forests

NMW

SMNIDP HELP SEWTP

NGP NCHF

LAP

LAKE

SUPERIOR

LAKE MICHIGAN

LAKE

HURON

CANADA

0 50 100 MILES

0 50 100 KILOMETERS

Ecoregion boundary

Sample block (10 x 10 km)

Land-use/land-cover class

Water

Developed

Transitional

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Ice/Snow

EXPLANATION

MN

WI MI

Northern Lakes and

Forests Ecoregion

MINNESOTA

WISCONSIN

CANADA

LAKE

SUPERIOR

MICHIGAN

MICHIGAN

Hibbing Bemidji

Cloquet Superior Marquette

Brainerd

Escanaba

Sault

Sainte

Marie

Marinette

Seney National

Wildlife Refuge

BOUNDARY WATERS

CANOE AREA

WILDERNESS

“ U P P E R P E N I N S U L A ”

L A K E

M I C H I G A N

Duluth

M E S A B I R A N G E

LAKE

HURON

Ecoregion Description 

The Northern Lakes and Forests Ecoregion covers 

189,889 km2 (73,316 mi2) across the northern parts of 

Minnesota, Wisconsin, and Michigan along the Great 

Lakes (fig. 1) (Omernik, 1987; Wiken and others, 2011). 

The ecoregion is bordered by the Northern Minnesota 

Wetlands Ecoregion to the northwest and the North Central 

Hardwood Forests Ecoregion to the west and south, as well 

as the Southern Michigan/Northern Indiana Drift Plains and 

Huron/Erie Lake Plains Ecoregions to the south. Much of the 

ecoregion was covered by the Laurentide ice sheet during the 

Pleistocene Wisconsin-age glaciation (Albert, 1995), which 

greatly influenced modern topography. It is a region of nutrientpoor glacial soils, coniferous and northern-hardwood forests, 

undulating till plains, morainal hills, broad lacustrine basins, 
34 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Figure 2. Corn field next to grazing livestock in Northern Lakes 

and Forests Ecoregion.

and extensive sandy outwash plains (U.S. Environmental 

Protection Agency, 2013). Lakes and wetlands are widespread 

across the ecoregion.

A moist-to-humid, midlatitude boreal climate 

characterizes the Northern Lakes and Forests Ecoregion. 

Summers are warm, with average high temperatures of 25°C 

to 28°C, and winters are cold, with average low temperatures 

of -20°C to -12°C (Keys and others, 1995). The Great Lakes 

strongly influence the climate and biota of the ecoregion, 

affecting the timing and amount of precipitation and also 

the length of the growing season, as well as moderating 

temperature extremes. Annual precipitation ranges from 

about 660 to 910 mm (26 to 36 in.) across the ecoregion

(Omernik and others, 2000). In late spring and summer, 

lake temperatures generally are cooler than the surrounding 

atmosphere, preventing air temperatures from rising higher 

than they would without the lake effect in this continental 

region; the reverse effect moderates winter temperatures. 

Mixed broadleaf-coniferous forests cover the ecoregion. 

Native tree species include jack pine (Pinus banksiana), 

balsam fir (Abies balsamea), black spruce (Picea mariana), 

and white spruce (Picea glauca). Common hardwoods 

include quaking aspen (Populus tremuloides), bigtooth aspen 

(Populus grandidentata), sugar maple (Acer saccharum), red 

maple (Acer rubrum), yellow birch (Betula alleghaniensis), 

paper birch (Betula papyrifera), American basswood (Tilia 

americana), and oak (Quercus spp.) (Schulte and others, 

2007). Wetland and riparian species are prolific and include 

a variety of sedges (Carex spp.) and sphagnums (Sphagnum 

spp.) (Schulte and others, 2007). Agriculture is limited by 

sandy soils, low temperatures, and a short frost-free period, 

unlike conditions in the agriculture-dominated ecoregions 

to the south (Omernik and others, 2000). Where agriculture 

is possible, hay, corn, and soybeans are the most common 

crops. Livestock grazing also accounts for a large part of the 

agricultural lands in the ecoregion (fig. 2). 

Most of the ecoregion is sparsely populated; the largest 

cities (and their 2000 populations) are Duluth, Minnesota 

(86,918); Superior, Wisconsin (27,368); and Marquette, 

Michigan (19,661) (U.S. Census Bureau, 2012). Most towns 

in the ecoregion are small, with much of the development 

concentrated around the many lakes there. The economy 

primarily is based on forestry, mining, and seasonal tourism. 

The Northern Lakes and Forests Ecoregion has had a 

long history of iron, copper, and sand and gravel aggregate 

mining. Following the discovery of iron and copper in the 

1840s, the population grew rapidly. More mineral wealth 

was amassed from Michigan’s “Upper Peninsula” alone 

than was made from the California Gold Rush (Dunbar and 

May, 1995). Copper mining began to decline in the late 19th 

century because of competition from Arizona and Montana. 

Michigan’s last operating copper mine closed in 1997 

(Michigan Department of Natural Resources, 2011). Mining 

of iron ore remains important, particularly in the Mesabi 

Range (fig. 3), in Hibbing, Minnesota, home of the world’s 

largest open-pit iron mine (Minnesota Department of Natural 

Resources, 2011). Minnesota is the largest producer of iron 

ore and taconite (an iron-bearing sedimentary rock) in the 

United States (Minnesota Department of Natural Resources, 

2011). Most of the mining in other parts of the ecoregion 

consists of rock quarries and sand and gravel pits that produce 

construction materials (fig. 4). 

Nationally, the clearing of forests for fuel, timber, and 

other wood products, as well as the opening the land for crops, 

led to a widespread loss of forest land that lasted through 

the early 1900s (U.S. Geological Survey, 1998). This pattern 

occurred in the Northern Lakes and Forests Ecoregion, as 

timber harvesting and forest regrowth were the dominant 

land-cover changes during the late 20th century. Trees in 

the ecoregion primarily were harvested for wood pulp and 

construction materials, and the forests had fairly rapid rates of 

regrowth. This ecoregion has been one of the most intensively 

logged geographic areas in the United States. Logging often 

was followed by slash burning practices until fire suppression 

was implemented in the 1930s (Rhemtulla and others, 

2009). Since then, many areas have been allowed to regrow 

“naturally;” however, pre–European settlement conditions 

have not yet been achieved (Schulte and others, 2007). 

Contemporary Land-Cover Change 

(1973 to 2000)

The overall spatial change (the percentage of land area 

that changed at least one time) in the Northern Lakes and 

Forests Ecoregion between 1973 and 2000 is estimated at 

12.2percent (23,166 km2) (table 1). Compared to other 

Midwest–South Central United States ecoregions, change 

in the Northern Lakes and Forests Ecoregion was the third 

highest (fig.5): about 5.4 percent (10,254 km2) of the area 

changed only once during the study period, 5.0 percent 

(9,494 km2) changed twice, 1.7 percent (3,228 km2) changed 

three times, and 0.1percent (190 km2) changed four times 
Chapter 2—Northern Lakes and Forests Ecoregion 35

Figure 3. Map showing locations of known mines (historical and current) and major population centers (that is, cities and towns 

having populations greater than 10,000) in Northern Lakes and Forests Ecoregion (National Atlas of the United States, 2004; U.S. 

Geological Survey, 2005).

Figure 4. Sand and gravel mining activity in Northern Lakes and 

Forests Ecoregion.

Figure 5. Overall spatial change in Northern Lakes and Forests 

Ecoregion (NLF; darker bars) compared with that of all 17 Midwest–

South Central United States ecoregions (lighter bars). Each 

horizontal set of bars shows proportions of ecoregion that changed 

during one, two, three, or four time periods; highest level of spatial 

change in Northern Lakes and Forests Ecoregion (four time periods) 

labeled for clarity. See table 2 for years covered by each time 

period. See appendix 2 for key to ecoregion abbreviations.

0 12 24 36

Area, as percent of ecoregion

Ecoregion 

DA

HELP

CCBP

SMNIDP

NCHF

BM

IRL

SEWTP

OH

EDP

ECBP

NMW

AV

MAP

NLF

SCP

OM

EXPLANATION

Change in one time period

Change in two time periods

Change in three time periods

Change in four time periods

Change in four time periods

(table1). Change during the study period increased from 

3.5percent of the ecoregion (6,612 km2) between 1973 and 

1980 to 7.0percent (13,316 km2) between 1992 and 2000 

(table2). When normalized to an average annual rate to 

account for uneven time periods, the period between 1986 and 

1992 experienced the greatest amount of change, at 1.0 percent 

(1,816 km2) (table 2; fig. 6). 

In 2000, forest was the predominant land-cover class in 

the Northern Lakes and Forests Ecoregion, accounting for 

61.7percent (117,165 km2) of the land area (table 3; fig. 7). 

Other major land-cover classes include wetland (18.9 percent; 

35,974 km2), water (7.4 percent; 14,020 km2), agriculture 

84°

94° 92° 90° 88° 86°

48°

46°

44° 0 50 100 150 Kilometers

Mines

 Iron

 Copper

 Sand and gravel agregate

Major city (population >10,000)

Major roadway

Sample block (10 km x 10 km)

Mining in the Northern Lakes and Forests EXPLANATION

Bemidji Hibbing

Cloquet Duluth

Superior

Escanaba

Sault Sainte Marie

Marinette

Brainerd

Marquette

MESABI RANGE

Bemidji Hibbing

Cloquet Duluth

Superior

Escanaba

Sault Sainte Marie

Marinette

Brainerd

Marquette

MESABI RANGE
36 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

0.5

0.0

1.0

1.5

2.5

3.0

2.0

3.5

1973 to 1980 1980 to 1986 1986 to 1992 1992 to 2000

Average annual change, as percent of ecoregion

Time period

Figure 6. Estimates of land-cover change per time period, 

normalized to annual rates of change for all 17 Midwest–South 

Central United States ecoregions (gray bars). Estimates of change 

for Northern Lakes and Forests Ecoregion are represented by red 

bars in each time period.

Figure 7. Forest in Northern Lakes and Forests Ecoregion. As 

predominant land-cover class in ecoregion, it accounts for about 

61.7 percent of ecoregion area in 2000. 

(5.8percent; 10,929 km2), mechanically disturbed (3.0 

percent; 5,630 km2), and grassland/shrubland (2.2 percent; 

4,242 km2) (table 3). Between 1973 and 2000, significant net 

changes in land-cover classes in relation to total ecoregion area 

included losses of forest (2.8 percent; 5,408 km2) and wetland 

(0.2percent; 333 km2), as well as gains in mechanically 

disturbed (which more than doubled, from 1.4 to 3.0 percent, 

expanding by 3,058 km2), grassland/shrubland (0.9 percent; 

1,653 km2), agriculture (0.3 percent; 538 km2), developed 

(0.2percent; 302 km2), and water (0.1 percent; 122 km2) 

(table3; fig. 8).

At least 71.2 percent (28,259 km2) of all land-cover 

conversions between 1973 and 2000 were associated with 

timber harvest and forest regeneration (table 4); note that 

land-cover change from grassland/shrubland to forest can have 

multiple origins and, thus, cannot be entirely associated with 

timber harvest and forest regeneration. Forest cutting (forest 

to mechanically disturbed, 15,585 km2) and subsequent forest 

regeneration (mechanically disturbed to forest, 6,534 km2), 

as well as successional regrowth (mechanically disturbed to 

grassland/shrubland, 6,140 km2; grassland/shrubland to forest, 

5,030 km2) are included in this estimate (table 4). The largest 

loss of forest occurred during the period between 1992 and 

2000, when 5,420 km2 of forest was cut (table 4). 

Wildland fire events (nonmechanical disturbance) also 

can influence land-cover change in the Northern Lakes and 

Forests Ecoregion, as shown in table 4. The lightning-ignited 

“Seney fire,” which started in August 1976 within Seney 

National Wildlife Refuge on Michigan’s “Upper Peninsula” 

(Anderson, 1982), is represented by the conversion from forest 

to nonmechanically disturbed in the period between 1973 

and 1980 (table 4). This fire accounted for 9.3 percent of all 

changes in that time period, as well as considerable change 

in the period between 1980 and 1986 (through post–fire 

recovery) (table4). Severe drought in the region created

unseasonably dry conditions that enabled the fire to spread 

rapidly, and attempts to extinguish it were hampered by 

limited access and the presence of standing water and dense 

brush (Anderson, 1982).

The mining land-cover class only accounted for 0.3 

percent of the ecoregion in 2000, which is surprisingly low 

given the extensive mining history of the area. Major mining 

activities and locations, such as the iron-ore–producing 

Mesabi Range, were geographically concentrated in certain 

areas and were not widespread throughout the entire 

ecoregion, which potentially complicated regional sampling 

(fig. 3). The economic and environmental effects of mines on 

the ecoregion likely are much larger than the small size of the 

land area affected relative to the total area of the ecoregion.

Forest harvest has been the main driver of land-use/landcover change in the Northern Lakes and Forests Ecoregion 

since the mid-19th century. Logging increased notably 

between 1992 and 2000. After normalizing to an annual rate 

of change to account for the varying lengths in study periods, 

the amount of forest area cleared per year more than doubled 

after 1980, after which it remained roughly constant at 630 to 

690 km2 per year. This trend is mirrored in the southeastern 

United States, but it is the opposite of what has been observed 

in much of the western United States (figs. 9,10; see also, 

Drummond and Loveland, 2010; Sleeter and others, 2012).

Land ownership plays a significant role in how forests 

are managed and protected. Examination of overall spatial 

change (on a block-by-block basis) and land ownership in 

the Northern Lakes and Forests Ecoregion shows change 

occurring on both publicly managed lands and private 

landholdings (fig. 11). High rates of change are seen on both 

ownership types; however, the western part of the ecoregion 

experienced higher overall spatial change during the study 

period. The exception was wilderness areas that had complete 

landscape protection, as is reflected by the 1.6 percent change 
Chapter 2—Northern Lakes and Forests Ecoregion 37

Figure 10. Piles of birch and aspen logs in Northern Lakes and 

Forests Ecoregion. 

Figure 9. Recent logging activity in Northern Lakes and Forests 

Ecoregion. 

Figure 8. Normalized average net change in Northern Lakes 

and Forests Ecoregion by time period for each land-cover class. 

Bars above zero axis represent net gain, whereas bars below zero 

represent net loss. Note that not all land-cover classes shown 

in explanation may be represented in figure. See appendix 3 for 

definitions of land-use and land-cover classifications.

−2

−1

0

1

2

1973–1980 1980–1986 

Time period

1986–1992 1992–2000 

Area changed, as percent of ecoregion 

Water

Developed

Mechanically disturbed

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Nonmechanically disturbed

Ice/Snow

EXPLANATION

LAND-USE/LAND-COVER CLASS

early-successional-stage and secondary-growth forests 

is attributable directly to land-use changes and natural 

disturbances (Ravenscroft and others, 2010). Much of the oldgrowth forests that remain are within the Boundary Waters 

Canoe Area Wilderness. 

Homogenization of forest stands decreases overall 

forest health, resiliency, and sustainability, and it also alters 

the nutrient cycle, species interactions, habitat quality, and 

other ecosystem services (Schulte and others, 2007). Future 

changes in climate are projected to decrease forest productivity 

(Ravenscroft and others, 2010) by increasing stressors on 

species at the limits of their range. The Northern Lakes and 

Forests Ecoregion has been susceptible to catastrophic, droughtinduced fire in the past, with fire as a key element in the 

ecoregion’s dynamic landscape for millennia; however, current 

temperature trends may accelerate wildfire occurrence and 

affect tree mortality in the future by increasing fire susceptibility 

and severity owing to increased fuel loads (Kling and others, 

2003). The complex land-ownership mosaic also brings with it 

a unique set of management challenges that will be pivotal in 

determining the sustained delivery of ecosystem services under 

continued patterns of historical land-use/land-cover change. 

in the block that lies within the Boundary Waters Canoe Area 

Wilderness (fig. 11). Outside protected areas, the primary 

factors that limited logging activity likely are related to 

restricted road access, distance to market, and target-species 

availability. The west is more populated, and it has larger 

shipping ports and a denser road network than the east. The 

26.2 percent overall spatial change that occurred in a single 

sample block in the east likely is inflated owing to the 1976 

“Seney fire,” which burned over 10 percent of the entire 

block, and also to subsequent changes related to landscape 

recovery after the fire. 

Because of a long period of high-intensity timber 

harvest, forest composition and structure have changed 

significantly. By the end of the study period, forest 

conditions were marked by lower species diversity, younger 

trees, smaller average tree diameter, and decreased forest 

complexity (Rhemtulla and others, 2009). Broad-leafed 

deciduous species such as aspen (Populus spp.) and maple 

(Acer spp.) have become more common, whereas conifer 

dominance has decreased (Schulte and others, 2007). 

The replacement of old-growth coniferous forests with 
38 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Figure 11. Map of public lands in Northern Lakes and Forests Ecoregion, showing sample-block locations and overall spatial change 

values (as percent of sample-block area) (U.S. Geological Survey, 2010). Red circle shows location of sample block that has change 

value of 26.2 percent; “Seney fire,” which burned over 10 percent of this block and also parts of Seney National Wildlife Refuge in 1976, 

likely contributed greatly to this comparatively high change value.

94° 92° 90° 88° 86° 84°

48°

46°

44°

Public lands

 Wilderness

 National Forest

 National Park, National Monument,

 Natiomal Wildlife Refuge

 Natural Area, Natural Preserve

 State Forest, State Game Area

 State Park, State Recreation Area

 State Wildlife Area

 Fisheries Management Area

Land enrolled in Conservation Reserve Program

Sample block (10 × 10 km), showing overall spatial 

 change (as percent of sample block area)

EXPLANATION

0 50 100 150 200 KILOMETERS

Boundary Waters

Canoe Area

Wilderness

Isle Royale 

National

Park

Voyageurs

National

Park

Pictured Rocks

National

Lakeshore

Seney

National

Wildlife 

Refuge

Hiawatha

National 

Forest

Lake

Superior

State Forest

Hiawatha

National

Forest

Chequamegon

National

Forest Chequamegon

National

Forest

Chequamegon

National

Forest

Ottawa

National

Forest

 Northern

 Highland—

American

Legion State

Forest

Escanaba River

State Forest

Porcupine

Mountains

Wilderness

State Park

Apostle

Islands

National

Lakeshore

Crex

Meadows

State Wildlife Area

Mille Lacs Wildlife

Management Area

Superior

National

Forest

Chippewa

National

Forest

Savanna

State

Forest

George

Washington

State

Forest

Solana

State

Forest

Tamarac

National

Wildlife

Refuge

Paul

Bunyan

State

Forest

Itasca

State

Park

Beaver 

Islands

State Wildlife

Research 

Area

Huron National

Forest

Manistee

National

Forest

Au Sable

State Forest

Pere

Marquette

State Forest

Munuscong

Wildlife

Management

Area

Escanaba River

State Forest

Nicolet

National

Forest

Superior National

Forest

Brule

River

State

Forest

Tahquamenon

Falls State Park

Rice Lake

National

Wildlife

Refuge

4.6

13.3

11.2

17.0 30.4

7.4

18.1 9.8

6.4

22.5

1.6

24.9

22.5

33.9

16.5 13.2

9.7

4.4

12.0

3.8

8.5 3.9

21.2

3.7

12.5

0.1 12.2

8.1

3.4

26.2

18.4

3.2
Chapter 2—Northern Lakes and Forests Ecoregion 39

Table 1. Percentage of Northern Lakes and Forests Ecoregion 

land cover that changed at least one time during study period 

(1973–2000) and associated statistical error.

[Most sample pixels remained unchanged (87.5 percent), whereas 12.5 percent 

changed at least once throughout study period]

Number

of

changes

Percent

of

ecoregion

Margin

of error

(+/− %)

Lower

bound

(%)

Upper

bound

(%)

Standard

error

(%)

Relative

error

(%)

1 5.4 0.9 4.5 6.2 0.6 11.2

2 5.0 1.0 4.0 6.0 0.7 13.4

3 1.7 0.6 1.1 2.3 0.4 22.8

4 0.1 0.1 0.0 0.1 0.0 43.8

Overall 

spatial 

change

12.2 2.1 10.1 14.3 1.4 11.8

Table 2. Raw estimates of change in Northern Lakes and Forests Ecoregion land cover, 

computed for each of four time periods between 1973 and 2000, and associated error at 

85-percent confidence level.

[Estimates of change per period normalized to annual rate of change for each time period]

Period

Total 

change

(% of

ecoregion)

Margin of 

error

(+/− %)

Lower 

bound

(%)

Upper 

bound

(%)

Standard 

error

(%)

Relative 

error

(%)

Average 

rate

(% per 

year)

Estimate of change, in percent stratum

1973–1980 3.5 1.0 2.5 4.5 0.7 19.5 0.5

1980–1986 4.7 1.1 3.6 5.7 0.7 15.7 0.8

1986–1992 5.7 1.0 4.7 6.8 0.7 12.3 1.0

1992–2000 7.0 1.4 5.6 8.4 0.9 13.5 0.9

Estimate of change, in square kilometers

1973–1980 6,612 1,899 4,713 8,511 1,287 19 945

1980–1986 8,852 2,054 6,799 10,906 1,391 16 1,475

1986–1992 10,896 1,977 8,919 12,872 1,339 12 1,816

1992–2000 13,316 2,650 10,665 15,966 1,796 13 1,664
40 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Table 3. Estimated area (and margin of error) of each land-cover class in Northern Lakes and Forests Ecoregion, calculated five times 

between 1973 and 2000. See appendix 3 for definitions of land-cover classifications.

Water Developed Mechanically 

disturbed Mining Barren Forest Grassland/Shrubland Agriculture Wetland

Nonmechanically 

disturbed

% +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/−

Area, in percent stratum

1973 7.3 4.2 0.5 0.2 1.4 0.5 0.3 0.4 0.0 0.0 64.5 4.6 1.4 1.1 5.5 1.7 19.1 3.7 0.0 0.0

1980 7.4 4.2 0.6 0.2 1.2 0.5 0.3 0.4 0.0 0.0 63.7 4.5 2.0 0.9 5.6 1.8 19.0 3.7 0.3 0.5

1986 7.5 4.2 0.6 0.2 2.1 0.5 0.2 0.3 0.0 0.0 62.7 4.4 2.2 0.9 5.7 1.8 18.9 3.7 0.0 0.0

1992 7.4 4.2 0.6 0.3 2.2 0.5 0.3 0.3 0.0 0.0 62.1 4.3 2.6 0.9 5.8 1.8 19.0 3.7 0.0 0.0

2000 7.4 4.2 0.7 0.3 3.0 0.7 0.3 0.3 0.0 0.0 61.7 4.3 2.2 1.0 5.8 1.8 18.9 3.7 0.0 0.1

Net

change 0.1 0.1 0.2 0.1 1.6 0.7 0.0 0.0 0.0 0.0 –2.8 0.9 0.9 0.5 0.3 0.2 –0.2 0.1 0.0 0.1

Gross

change 0.5 0.2 0.2 0.1 4.5 0.8 0.1 0.0 0.0 0.0 6.0 1.1 3.3 0.9 0.6 0.2 0.7 0.2 0.7 1.0

Area, in square kilometers

1973 13,899 7,974 1,038 401 2,572 876 516 681 5 5 122,572 8,651 2,589 2,027 10,391 3,306 36,307 7,000 0 0

1980 14,021 8,022 1,083 424 2,268 910 505 677 5 5 120,963 8,503 3,716 1,746 10,606 3,349 36,104 6,967 616 902

1986 14,221 8,040 1,158 453 4,015 940 470 604 5 5 119,102 8,432 4,157 1,616 10,891 3,392 35,869 6,983 0 0

1992 14,070 8,000 1,219 485 4,238 919 495 606 5 5 117,955 8,076 4,916 1,744 10,949 3,387 36,041 6,987 0 0

2000 14,020 8,026 1,340 550 5,630 1,300 499 612 5 5 117,165 8,089 4,242 1,829 10,929 3,384 35,974 6,941 85 124

Net

change 122 122 302 182 3,058 1,350 –17 72 0 0 –5,408 1,690 1,653 873 538 448 –333 261 85 124

Gross

change 902 299 326 181 8,621 1,560 129 95 1 1 11,345 2,055 6,236 1,623 1,079 422 1,403 337 1,318 1,928
Chapter 2—Northern Lakes and Forests Ecoregion 41

Table 4. Principal land-cover conversions in Northern Lakes and Forests Ecoregion, showing amount of area changed (and margin 

of error, calculated at 85-percent confidence level) for each conversion during each of four time periods and also during overall 

study period. See appendix 3 for definitions of land-cover classifications.

[Values given for “other” class are combined totals of values for other land-cover classes not listed in that time period. Abbreviations: n/a, not applicable]

Period From class To class

Area 

changed

Margin of 

error

Standard 

error Percent of 

ecoregion

Percent of all 

changes (km2) (+/− km2) (km2)

1973–1980 Forest Mechanically disturbed 2,219 908 615 1.2 33.6

Mechanically disturbed Grassland/Shrubland 1,419 559 379 0.7 21.5

Mechanically disturbed Forest 1,108 513 347 0.6 16.8

Forest Nonmechanically disturbed 616 902 611 0.3 9.3

Grassland/Shrubland Forest 354 348 236 0.2 5.4

Other Other 895 n/a n/a 0.5 13.5

Totals 6,612 3.5 100.0

1980–1986 Forest Mechanically disturbed 3,814 927 628 2.0 43.1

Mechanically disturbed Grassland/Shrubland 1,090 536 363 0.6 12.3

Mechanically disturbed Forest 1,059 491 333 0.6 12.0

Grassland/Shrubland Forest 920 391 265 0.5 10.4

Nonmechanically disturbed Grassland/Shrubland 315 460 312 0.2 3.6

Other Other 1,654 n/a n/a 0.9 18.7

Totals 8,852 4.7 100.0

1986–1992 Forest Mechanically disturbed 4,131 915 620 2.2 37.9

Mechanically disturbed Grassland/Shrubland 2,057 686 465 1.1 18.9

Mechanically disturbed Forest 1,779 471 319 0.9 16.3

Grassland/Shrubland Forest 1,397 492 333 0.7 12.8

Water Wetland 275 144 98 0.1 2.5

Other Other 1,255 n/a n/a 0.7 11.5

Totals 10,896 5.7 100.0

1992–2000 Forest Mechanically disturbed 5,420 1,285 870 2.9 40.7

Mechanically disturbed Forest 2,588 733 496 1.4 19.4

Grassland/Shrubland Forest 2,359 812 550 1.2 17.7

Mechanically disturbed Grassland/Shrubland 1,574 628 425 0.8 11.8

Water Wetland 219 76 51 0.1 1.6

Other Other 1,156 n/a n/a 0.6 8.7

Totals 13,316 7.0 100.0

1973–2000

(overall)

Forest Mechanically disturbed 15,585 3,443 2,332 8.2 39.3

Mechanically disturbed Forest 6,534 1,611 1,092 3.4 16.5

Mechanically disturbed Grassland/Shrubland 6,140 2,043 1,384 3.2 15.5

Grassland/Shrubland Forest 5,030 1,520 1,030 2.6 12.7

Forest Agriculture 827 338 229 0.4 2.1

Other Other 5,559 n/a n/a 2.9 14.0

Totals 39,676 20.9 100.0
42 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

References Cited

Albert, Dennis A., 1995, Regional landscape ecosystems of 

Michigan, Minnesota, and Wisconsin—A working map and 

classification: U.S. Forest Service, North Central Forest 

Experiment Station, General Technical Report NC-178, 

accessed March 2, 2011, at http://www.npwrc.usgs.gov/

resource/habitat/rlandscp/index.htm.

Anderson, S.H., 1982, Effects of the 1976 Seney National 

Wildlife Refuge wildfire on wildlife and wildlife habitat: U.S. 

Fish and Wildlife Service, Resource Publication 146, 29 p. 

Drummond, M.A., and Loveland, T.R., 2010, Land-use pressure 

and a transition to forest-cover loss in the eastern United 

States: Bioscience, v. 60, p. 286–298.

Dunbar, W.F., and May, G.S., 1995, Michigan—A history of the 

Wolverine State (3d ed.): Grand Rapids, Mich., William B. 

Eerdmans Publishing Co., 718 p. 

Keys, J., Carpenter, C., Hooks, S., Koenig, F., McNab, W.H., 

Russell, W., and Smith, M.L., 1995, Ecological units of the 

Eastern United States—First approximation: U.S. Forest 

Service report, accessed February 1, 2013, at http://www.srs.

fs.usda.gov/econ/data/keys/readme.1st.

Kling, G.W., Hayhoe, K., Johnson, L.B., Magnuson, J.J., 

Polasky, S., Robinson, S.K., Shuter, B.J., Wander, M.M., 

Wuebbles, D.J., Zak, D.R., Lindroth, R.L., Moser, S.C., and 

Wilson, M.L., 2003, Confronting climate change in the Great 

Lakes region—Impacts on our communities and ecosystems: 

Union of Concerned Scientists and Ecological Society of 

America, 58 p., available at http://www.ucsusa.org/assets/

documents/global_warming/greatlakes_final.pdf.

Michigan Department of Natural Resources, 2011, Mining in 

Michigan, Michigan Historical Museum—Copper mining: 

Michigan Department of Natural Resources Web site, accessed 

March 2, 2011, at http://www.hal.state.mi.us/mhc/museum/

explore/museums/hismus/prehist/mining/copper.html.

Minnesota Department of Natural Resources, 2011, Taconite: 

Minnesota Department of Natural Resources Web site, 

accessed March 2, 2011, at http://www.dnr.state.mn.us/

education/geology/digging/taconite.html.

National Atlas of the United States, 2004, Cities and towns 

of the United States: National Atlas of the United States 

database, accessed April 12, 2011, at http://nationalatlas.gov/

mld/citiesx.html.

Omernik, J.M., 1987, Ecoregions of the conterminous United 

States: Annals of the Association of American Geographers, 

v. 77, no. 1, p. 118–125.

Omernik, J.M., Chapman, S.S., Lillie, R.A., and Dumke, R.T., 

2000, Ecoregions of Wisconsin: Transactions of the Wisconsin 

Academy of Sciences, Arts, and Letters, v. 88, p. 77–103.

Ravenscroft, C., Scheller, R.M., Mladenoff, D.J., and White, 

M.A., 2010, Forest restoration in a mixed-ownership 

landscape under climate change: Ecological Applications, v. 

20, no. 2, p. 327–346.

Rhemtulla, J.M., Mladenoff, D.J., and Clayton, M.K., 2009, 

Legacies of historical land use on regional forest composition 

and structure in Wisconsin, USA (mid-1800s – 1930s – 

2000s): Ecological Applications, v. 19, no. 4, p. 1,061–1,078. 

Schulte, L.A., Mladenoff, D.J., Crow, T.R., Merrick, L.C., and 

Cleland, D.T., 2007, Homogenization of northern U.S. Great 

Lakes forests due to land use: Landscape Ecology, v. 22, p. 

1,089–1,103. 

Sleeter, B.M., Wilson, T.S., and Acevedo, W., eds., 2012, 

Status and trends of land change in the Western United 

States—1973 to 2000: U.S. Geological Survey Professional 

Paper 1794–A, 324 p., available at http://pubs.usgs.gov/

pp/1794/a/.

U.S. Census Bureau, 2012, State and county quick facts: U.S. 

Census Bureau database, accessed February 11, 2013, at 

http://quickfacts.census.gov/qfd/index.html.

U.S. Environmental Protection Agency, 2013, Level III and IV 

ecoregions of the continental United States: U.S. Environmental 

Protection Agency database, accessed October 22, 2015, at ftp://

ftp.epa.gov/wed/ecoregions/us/Eco_Level_IV_US.pdf.

U.S. Geological Survey, 1998, Status and trends of the Nation’s 

biological resources, volumes 1 and 2: U.S. Geological Survey, 

National Wetlands Research Center, accessed February 11, 

2013, at http://www.nwrc.usgs.gov/sandt/SNT.pdf.

U.S. Geological Survey, 2005, Mineral resources data system: 

U.S. Geological Survey Mineral Resources database, 

accessed April 12, 2011, at http://tin.er.usgs.gov/mrds/.

U.S. Geological Survey, 2010, Protected areas database of 

the United States (PADUS): U.S. Geological Survey Gap 

Analysis Program/Protected Areas Data Portal, accessed 

February 1, 2013, at http://gapanalysis.usgs.gov/padus/.

Vogelmann, J.E., Howard, S.M., Yang, L., Larson, C.R., Wylie, 

B.K., and van Driel, N., 2001, Completion of the 1990s 

National Land Cover Data Set for the conterminous United 

States from Landsat Thematic Mapper data and ancillary 

data sources: Photogrammetric Engineering & Remote 

Sensing, v. 67, p. 650–662.

Wiken, E., Jiménez Nava, F., and Griffith, G., 2011, North 

American terrestrial ecoregions—Level III: Montreal, 

Canada, Commission for Environmental Cooperation, 

149 p., accessed February 1, 2013, at http://www.cec.org/

Storage/133/15860_QA07.30-32_NP_NA_Terrestrial_

Ecoregions_Level_3_Final-2june11.pdf. 
Northern Agriculture-Forest Transition Zone Ecoregions

Chapter 3

Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000 

Edited by Roger F. Auch and Krista A. Karstensen 

U.S. Geological Survey Professional Paper 1794–C, 2015

North Central Hardwood Forests Ecoregion

By Christopher A. Barnes

Figure 1. Map of North Central Hardwood Forests Ecoregion and surrounding ecoregions, showing land-use/land-cover classes from 

1992 National Land Cover Dataset (Vogelmann and others, 2001); note that not all land-use/land-cover classes shown in explanation 

may be depicted on map; note also that, for this “Status and Trends of Land Change” study, transitional land-cover class was subdivided 

into mechanically disturbed and nonmechanically disturbed classes. Squares indicate locations of 10 x 10 km sample blocks analyzed 

in study. Index map shows locations of geographic features mentioned in text. Abbreviations for Midwest–South Central United States 

ecoregions are listed in appendix 2. Also shown are parts of three Great Plains ecoregions: Lake Agassiz Plain, Northern Glaciated 

Plains, and Western Corn Belt Plains. See appendix 3 for definitions of land-use/land-cover classifications.

Ecoregion Description 

The North Central Hardwood Forests Ecoregion, about 

91,205 km2 (35,214 mi2) in size, encompasses parts of 

Minnesota, Wisconsin, and Michigan (fig. 1) (Omernik, 1987). 

The ecoregion bridges the predominantly forested ecoregions 

that neighbor it to the north (Northern Lakes and Forests 

Ecoregion, Northern Minnesota Wetlands Ecoregion) and 

the more agricultural ecoregions that surround it to the south 

and west (Southern Michigan/Northern Indiana Drift Plains, 

Southeastern Wisconsin Till Plains, Driftless Area, Western 

Corn Belt Plains, Northern Glaciated Plains, and Lake Agassiz 

94° 92° 90° 88° 86°

96° 94°

48°

46°

44°

Northern

Lakes and Forests

NLF

Western

Corn Belt Plains Driftless Area

Lake

Agassiz

Plain

Northern

Glaciated

Plains

SMNIDP SEWTP

NMW

LAKE

SUPERIOR

LAKE MICHIGAN

0 50 100 MILES

0 50 100 KILOMETERS

Ecoregion boundary

Sample block (10 x 10 km)

Land-use/land-cover class

Water

Developed

Transitional

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Ice/Snow

EXPLANATION

MINNESOTA

MN

WI

MI

MI

North Central Hardwood

Forests Ecoregion

River

Eau Claire

Wausau 

Wisconsin

Rapids

Stevens

Point Green

Bay

Otter Tail

Lake

Lake Osakis

Saint Cloud

Cottage Grove

Anoka Stillwater

Minneapolis Saint Paul

WISCONSIN

MINNESOTA

LAKE CANADA

SUPERIOR

MI

MICHIGAN

L A K E

M I C H I G A N

Mississippi

Plain Ecoregions). The ecoregion’s growing season generally 

is longer and warmer than that of the Northern Lakes and 

Forests Ecoregion, and its more arable and fertile soils support 

agricultural land use over a larger extent than its northern 

neighbors. Lakes in the North Central Hardwood Forests 

Ecoregion typically have higher trophic-state-index values than 

those in the Northern Lakes and Forests Ecoregion, having 

higher percentages in the eutrophic and hypereutrophic classes. 

The mostly flat landscape of the North Central Hardwood 

Forests Ecoregion consists of a mosaic of forest and cropland 
46 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Figure 2. Overall spatial change in North Central Hardwood

Forests Ecoregion (NCHF; darker bars) compared with that of all 17 

Midwest–South Central United States ecoregions (lighter bars). Each 

horizontal set of bars shows proportions of ecoregion that changed 

during one, two, three, or four time periods; highest level of spatial 

change in North Central Hardwood Forests Ecoregion (four time 

periods) labeled for clarity. See table 3 for years covered by each 

time period. See appendix 2 for key to ecoregion abbreviations.

Figure 3. Estimates of land-cover change per time period, 

normalized to annual rates of change for all 17 Midwest–South 

Central United States ecoregions (gray bars). Estimates of change 

for North Central Hardwood Forests Ecoregion are represented by 

red bars in each time period.

agriculture, primarily pastureland and dairy operations 

interspersed with urban, suburban, and rural residential land. 

Larger cities include Minneapolis, Saint Paul, Saint Cloud, 

Anoka, and Stillwater, Minnesota, and Eau Claire, Wausau, 

Wisconsin Rapids, and Stevens Point, Wisconsin. In 2000, 

the ecoregion’s land cover was about 49.8 percent agriculture, 

27.1 percent forest, 8.5 percent water, and 8.3 percent wetland 

(table1). The ecoregion has a midlatitude humid continental 

climate, with warm summers, severe winters, and no 

pronounced dry season. The frost-free period ranges from 140 

to 170 days (Wiken and others, 2011), and the mean annual 

precipitation is 825 mm (32 in.), ranging from a minimum of 

760 mm (30 in.) to a maximum of 965 mm (38 in.) (Wiken and 

others, 2011).

Land cover of the North Central Hardwood Forests 

Ecoregion prior to European-American settlement was 

dominated by conifers such as red and white pine (Pinus 

resinosa and Pinus strobus, respectively), which regenerated 

originally when fires were less intense and not so widespread, 

mixed with hardwood species such as sugar maple (Acer 

saccharum) (Curtis, 1956). Grassland prairies and wetlands 

were intermixed within forest openings. Pioneer loggers 

were attracted to the region because of the abundance of 

white pine, a preferred wood for building; its lightweight, 

yet strong and durable, characteristics meant it was easy 

to work with and could be floated down rivers to markets 

with relative ease (Anderson and others, 1996). Over the 

last 150 years, the landscape of the North Central Hardwood 

Forests Ecoregion has experienced major land-cover changes 

that primarily are due to the extensive and rapid conversion 

of forests to cropland agriculture and urban development 

(Anderson and others, 1996). Timber harvesting and 

agriculture were important economic activities until the turn 

of the 20th century, when population patterns shifted and 

people from the farm moved to the city in search of jobs 

(Robinson, 1915; Borchert, 1987). By 1940, the number of 

farms, the total acres of farmland, and the percentage of land 

in farms began to decrease, a trend in agricultural land use 

that continued throughout the 27-year study period (Anderson 

and others, 1996). Although timber harvesting continues to be 

an important economic activity, its extent has decreased, and 

it is now more focused on different species than it was during 

its peak from 1898 to 1903, as white pine has become less 

plentiful (Anderson and others, 1996).

Contemporary Land-Cover Change

(1973 to 2000)

The overall spatial change (the percentage of land area 

that changed at least one time) in the North Central Hardwood 

Forests Ecoregion between 1973 and 2000 is estimated at 4.6 

percent (table 2). Compared to other Midwest–South Central 

United States ecoregions, change in the North Central Hardwood 

Forest Ecoregion was relatively low (fig. 2): an estimated 3.7 

percent of the ecoregion area changed only once during the study 

period (table 2). The percent of land-cover change gradually 

increased from 1973 to 2000, from a low of 0.8 percent, between 

0 12 24 36

Area, as percent of ecoregion

Ecoregion 

DA

HELP

CCBP

SMNIDP

NCHF

BM

IRL

SEWTP

OH

EDP

ECBP

NMW

AV

MAP

NLF

SCP

OM

EXPLANATION

Change in one time period

Change in two time periods

Change in three time periods

Change in four time periods

Change in four time periods

0.5

0.0

1.0

1.5

2.5

3.0

2.0

3.5

1973 to 1980 1980 to 1986 1986 to 1992 1992 to 2000

Average annual change, as percent of ecoregion

Time period
Chapter 3—North Central Hardwood Forests Ecoregion 47

Figure 4. Normalized average net change in North Central 

Hardwood Forests Ecoregion by time period for each land-cover 

class. Bars above zero axis represent net gain, whereas bars 

below zero represent net loss. Note that not all land-cover classes 

shown in explanation may be represented in figure. See appendix 

3 for definitions of land-use and land-cover classifications.

Figure 5. Different types of new developed land cover in 

North Central Hardwood Forests Ecoregion. A, Rural residential 

development, Cottage Grove, Minnesota. B, Lakeshore lots for sale 

near Lake Osakis, Minnesota. C, Signs for development on former 

agricultural land near Otter Tail Lake, Minnesota. 

−1

−0.5

0

0.5

1

1973–1980 1980–1986 

Time period

1986–1992 1992–2000 

Area changed, as percent of ecoregion 

Water

Developed

Mechanically disturbed

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Nonmechanically disturbed

Ice/Snow

EXPLANATION

LAND-USE/LAND-COVER CLASS

1973 and 1980, to a high of 2.2 percent, between 1992 and 2000 

(table 3). When normalized to account for uneven time periods, 

the average annual rate of change in the ecoregion (0.3 percent) 

was greatest between 1992 and 2000 (table 3).

The agriculture, developed, grassland/shrubland, and 

forest land-cover classes experienced observable net change 

during the study period (table 1; fig. 4). The agriculture class 

showed a net loss of 1,910 km2 (4.0 percent of its estimated 

1973 area) during the study period, and the developed class 

showed a net increase of 1,642 km2 (72.6 percent increase 

from its estimated 1973 area) (table 1). These changes 

primarily are attributable to metropolitan growth, new 

rural residential estates, and new lakeshore developments 

(fig. 5). Accelerating decreases in agriculture land cover 

in the ecoregion may have been influenced by the timber 

industry, as well as by the 1985 Farm Bill that established 

the Conservation Reserve Program (CRP) (table 4). These 

changes are shown by conversions from agriculture to forest 

and from agriculture to grassland/shrubland. Grassland/

shrubland increased by 21.7 percent, primarily from 

agriculture. This increase may represent agricultural land 

being enrolled in the CRP, or perhaps a period of early forest 

succession. The 0.8 percent loss in forest was caused by small 

amounts of forest clearance for residential and commercial 

development, primarily in the suburban regions of Saint 

Cloud and Minneapolis–Saint Paul, Minnesota, and also Eau 

Claire and Wisconsin Rapids, Wisconsin.

The leading land-cover conversion during the study 

period was from agriculture to developed (table 4). The 

ecoregion lost about 1,296 km2 of agricultural land to 

developed land between 1973 and 2000. Agricultural areas 

of the North Central Hardwood Forests Ecoregion have 

decreased, coming under increasing pressure from population 

increases, as well as the demand for executive-style houses 

A

B

C
48 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

and new second homes. The major conversion associated with 

timber harvesting (forest to mechanically disturbed) was the 

next most common land-cover conversion, indicative of the 

still-active and still-profitable timber industry (fig. 6A). Landcover changes associated with forest regrowth after harvest 

(mechanically disturbed to forest; fig. 6B) generally fell within 

the “other” category during the study period (table 4). 

Figure 6. Local timber-harvesting operations near Wisconsin Rapids, Wisconsin, in North Central Hardwood Forests Ecoregion. A, 

Timber logs stacked after harvesting. B, Tree farm. 

Overall, the ecoregion had little land-cover change 

in relation to other Midwest–South Central United States 

ecoregions, but this trend may change in the future as the 

four major urban centers located in this ecoregion continue to 

increase in population, and the resulting increase in developed 

land cover may continue to alter the extent of agriculture in 

the North Central Hardwood Forests Ecoregion.

A B
Chapter 3—North Central Hardwood Forests Ecoregion 49

Table 1. Estimated area (and margin of error) of each land-cover class in North Central Hardwood Forests Ecoregion, calculated five 

times between 1973 and 2000. See appendix 3 for definitions of land-cover classifications.

Water Developed

Mechanically 

disturbed

Mining Barren Forest Grassland/

Shrubland Agriculture Wetland

Nonmechanically 

disturbed

% +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/−

Area, in percent stratum

1973 8.5 4.4 2.5 0.9 0.0 0.0 0.0 0.0 0.0 0.0 27.3 4.8 1.3 0.5 51.9 5.2 8.4 1.9 0.0 0.0

1980 8.4 4.4 2.7 1.0 0.2 0.2 0.1 0.0 0.0 0.0 27.2 4.8 1.3 0.5 51.7 5.1 8.5 1.9 0.0 0.0

1986 8.5 4.4 3.1 1.2 0.1 0.1 0.1 0.0 0.0 0.0 27.1 4.7 1.4 0.5 51.3 5.1 8.3 1.9 0.0 0.0

1992 8.5 4.4 3.5 1.4 0.2 0.2 0.1 0.0 0.0 0.0 27.1 4.6 1.6 0.5 50.8 5.0 8.4 1.8 0.0 0.0

2000 8.5 4.4 4.3 2.0 0.3 0.2 0.1 0.0 0.0 0.0 27.1 4.6 1.6 0.5 49.8 5.0 8.3 1.9 0.0 0.0

Net

change 0.0 0.2 1.8 1.1 0.2 0.2 0.0 0.0 0.0 0.0 –0.2 0.6 0.3 0.2 –2.1 1.2 –0.1 0.2 0.0 0.0

Gross

change 0.6 0.3 1.8 1.1 0.8 0.5 0.1 0.0 0.0 0.0 1.5 0.6 0.8 0.3 2.5 1.1 0.7 0.3 0.0 0.0

Area, in square kilometers

1973 7,722 3,982 2,263 787 26 20 40 17 1 1 24,915 4,381 1,180 449 47,367 4,711 7,690 1,720 0 0

1980 7,681 3,980 2,478 915 143 157 46 19 1 1 24,842 4,354 1,164 448 47,123 4,684 7,727 1,720 0 0

1986 7,788 3,981 2,802 1,082 98 91 59 30 1 1 24,755 4,265 1,298 476 46,810 4,622 7,594 1,706 0 0

1992 7,713 3,974 3,158 1,307 202 158 66 40 1 1 24,674 4,218 1,420 494 46,315 4,584 7,655 1,676 0 0

2000 7,750 3,969 3,905 1,786 253 181 80 43 1 1 24,714 4,156 1,436 494 45,458 4,598 7,608 1,692 0 0

Net

change 28 137 1,642 1,036 227 180 40 29 0 0 –201 589 256 185 –1,910 1,062 –82 153 0 0

Gross

change 562 229 1,642 1,036 732 457 55 30 0 0 1,352 549 736 293 2,303 1,019 611 236 0 0
50 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Table 2. Percentage of North Central Hardwood Forests 

Ecoregion land cover that changed at least one time during study 

period (1973–2000) and associated statistical error.

[Most sample pixels remained unchanged (95.4 percent), whereas 4.6 percent 

changed at least once throughout study period]

Number

of

changes

Percent

of

ecoregion

Margin

of error

(+/− %)

Lower

bound

(%)

Upper

bound

(%)

Standard

error

(%)

Relative

error

(%)

1 3.7 1.2 2.5 4.9 0.8 22.7

2 0.6 0.3 0.3 1.0 0.2 32.4

3 0.2 0.1 0.0 0.3 0.1 51.1

4 0.0 0.0 0.0 0.0 0.0 54.2

Overall 

spatial 

change

4.6 1.4 3.1 6.0 1.0 21.0

Table 3. Raw estimates of change in North Central Hardwood Forests Ecoregion land cover, computed 

for each of four time periods between 1973 and 2000, and associated error at 85-percent confidence 

level.

[Estimates of change per period normalized to annual rate of change for each time period]

Period Total change

(% of ecoregion)

Margin of 

error

(+/− %)

Lower 

bound

(%)

Upper bound

(%)

Standard 

error

(%)

Relative 

error

(%)

Average rate

(% per year)

Estimate of change, in percent stratum

1973–1980 0.8 0.3 0.5 1.1 0.2 25.2 0.1

1980–1986 1.3 0.5 0.8 1.8 0.3 23.8 0.2

1986–1992 1.4 0.4 0.9 1.8 0.3 21.5 0.2

1992–2000 2.2 0.7 1.5 2.9 0.5 22.2 0.3

Estimate of change, in square kilometers

1973–1980 720 267 452 987 182 25 103

1980–1986 1,190 417 773 1,606 283 24 198

1986–1992 1,244 393 851 1,637 267 21 207

1992–2000 2,005 655 1,350 2,660 445 22 251
Chapter 3—North Central Hardwood Forests Ecoregion 51

Table 4. Principal land-cover conversions in North Central Hardwood Forests Ecoregion, showing amount of area changed (and 

margin of error, calculated at 85-percent confidence level) for each conversion during each of four time periods and also during 

overall study period. See appendix 3 for definitions of land-cover classifications.

[Values given for “other” class are combined totals of values for other land-cover classes not listed in that time period. Abbreviations: n/a, not applicable]

Period From class To class

Area 

changed

Margin of 

error

Standard 

error Percent of 

ecoregion

Percent of all 

changes (km2) (+/− km2) (km2)

1973–1980 Agriculture Developed 158 111 75 0.2 21.9

Forest Mechanically disturbed 128 156 106 0.1 17.7

Agriculture Forest 73 61 42 0.1 10.2

Grassland/Shrubland Forest 67 45 31 0.1 9.4

Water Wetland 64 43 29 0.1 8.9

Other Other 229 n/a n/a 0.3 31.9

Totals 720 0.8 100.0

1980–1986 Agriculture Developed 219 130 89 0.2 18.4

Wetland Water 133 61 41 0.1 11.2

Agriculture Grassland/Shrubland 126 54 37 0.1 10.6

Forest Agriculture 112 116 79 0.1 9.4

Agriculture Forest 108 82 56 0.1 9.1

Other Other 492 n/a n/a 0.5 41.4

Totals 1,190 1.3 100.0

1986–1992 Agriculture Developed 312 222 151 0.3 25.1

Forest Mechanically disturbed 170 154 105 0.2 13.6

Water Wetland 154 83 56 0.2 12.4

Agriculture Grassland/Shrubland 118 50 34 0.1 9.5

Mechanically disturbed Grassland/Shrubland 84 86 58 0.1 6.7

Other Other 407 n/a n/a 0.4 32.7

Totals 1,244 1.4 100.0

1992–2000 Agriculture Developed 607 466 317 0.7 30.3

Forest Mechanically disturbed 250 180 122 0.3 12.5

Grassland/Shrubland Forest 230 142 96 0.3 11.5

Agriculture Forest 150 98 66 0.2 7.5

Agriculture Grassland/Shrubland 133 69 47 0.1 6.6

Other Other 635 n/a n/a 0.7 31.7

Totals 2,005 2.2 100.0

1973–2000

(overall)

Agriculture Developed 1,296 907 616 1.4 25.1

Forest Mechanically disturbed 645 429 292 0.7 12.5

Grassland/Shrubland Forest 443 180 122 0.5 8.6

Agriculture Grassland/Shrubland 429 157 106 0.5 8.3

Agriculture Forest 399 274 186 0.4 7.7

Other Other 1,947 n/a n/a 2.1 37.7

Totals 5,158 5.7 100.0
52 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

References Cited

Anderson, O.B., Crow, T.R., Lietz, S.M., and Stearns, F., 

1996, Transformation of a landscape in the upper Midwest, USA—The history of the lower St Croix River valley, 

1830 to present: Landscape and Urban Planning, v. 35, p. 

247–267.

Borchert, J.R., 1987, America’s northern heartland: 

Minneapolis, University of Minnesota Press, 250 p.

Curtis, J.T., 1956, The modification of mid-latitude grasslands 

and forests by man, in Thomas, W.L., Jr., ed., Man’s role 

in changing the face of the Earth: Chicago and London, 

University of Chicago Press, p. 721–736.

Omernik, J.M., 1987, Ecoregions of the conterminous United 

States: Annals of the Association of American Geographers, 

v. 77, no. 1, p. 118–125.

Robinson, E.V., 1915, Early economic conditions and the 

development of agriculture in Minnesota: Minneapolis, 

University of Minnesota, 306 p.

Vogelmann, J.E., Howard, S.M., Yang, L., Larson, C.R., 

Wylie, B.K., and van Driel, N., 2001, Completion of the 

1990s National Land Cover Data Set for the conterminous 

United States from Landsat Thematic Mapper data and 

ancillary data sources: Photogrammetric Engineering & 

Remote Sensing, v. 67, p. 650–662.

Wiken, E., Jiménez Nava, F., and Griffith, G., 2011, North 

American terrestrial ecoregions—Level III: Montreal, 

Canada, Commission for Environmental Cooperation, 149 

p., accessed November 5, 2012, at http://www.cec.org/

Storage/133/15860_QA07.30-32_NP_NA_Terrestrial_

Ecoregions_Level_3_Final-2june11.pdf.
Chapter 4

Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000 

Edited by Roger F. Auch and Krista A. Karstensen 

U.S. Geological Survey Professional Paper 1794–C, 2015

Driftless Area Ecoregion

By Robert P. Glover

Figure 1. Map of Driftless Area 

Ecoregion and surrounding 

ecoregions, showing land-use/landcover classes from 1992 National 

Land Cover Dataset (Vogelmann 

and others, 2001); note that not all 

land-use/land-cover classes shown 

in explanation may be depicted on 

map; note also that, for this “Status 

and Trends of Land Change” study, 

transitional land-cover class was 

subdivided into mechanically 

disturbed and nonmechanically 

disturbed classes. Squares indicate 

locations of 10 x 10 km sample blocks 

analyzed in study. Index map shows 

locations of geographic features 

mentioned in text. Abbreviations for 

Midwest–South Central United States 

ecoregions are listed in appendix 2. 

Also shown is part of one Great Plains 

ecoregion, Western Corn Belt Plains. 

See appendix 3 for definitions of landuse/land-cover classifications.

93° 92° 91° 90°

45°

44°

43°

42°

Western Corn

Belt Plains

 North Central

Hardwood Forests

Central

Corn Belt

Plains

SEWTP

NLF

IA

IL

MN

WI Driftless

Area

Ecoregion

0 50 100 MILES

0 50 100 KILOMETERS

Ecoregion boundary

Sample block (10 x 10 km)

Land-use/land-cover class

Water

Developed

Transitional

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Ice/Snow

EXPLANATION

MINNESOTA WISCONSIN

IOWA

ILLINOIS

Dubuque

Rochester La Crosse

Madison

Eau Claire

M i s s i s s i p p i R i v e r

Saint Paul

Minneapolis

Ecoregion Description 

The Driftless Area Ecoregion covers about 47,590 km2

(18,375 mi2) of southeastern Minnesota, southwestern Wisconsin, 

and small parts of northeastern Iowa and northwestern Illinois. 

It is bordered by the following ecoregions: Western Corn Belt 

Plains Ecoregion to the southwest and west; North Central 

Hardwood Forests Ecoregion to the north and northeast; 

Southeastern Wisconsin Till Plains Ecoregion to the east; and 

Central Corn Belt Plains Ecoregion to the far southeast (fig. 1) 

(Omernik, 1987). The ecoregion has a humid continental climate 

that is split between the cool-summer subtype in the north and 

the warm-summer subtype in the south. Average minimum 

temperatures range from -17°C to -12°C, and average maximum 

temperatures range from 27°C to 29°C. The frost-free period 

ranges from 140 to 170 days (Wiken and others, 2011). Snowfall 

is common in the winter, and annual precipitation ranges from 

813 to 914 mm (31–37 in.) (Wiken and others, 2011; PRISM 

Climate Group, 2006).

Although evidence of glacial drift is found in the ecoregion, 

the presence of glacial deposits has not greatly influenced the 

landscape (Wiken and others, 2011), as it remains hilly with 

few natural lakes. Because the ecoregion was bypassed by the 

last continental glacier, it can be better characterized as karst 

topography, which results from differential weathering and 

erosion of carbonate rock (Driftless Area Initiative, 2012). The 

ecoregion contains few wetlands compared to its neighboring 

glaciated ecoregions (fig. 2). Most of the wetlands are associated 

with the Mississippi River, the major hydrologic feature of the 

ecoregion, as well as other rivers and streams.
54 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Figure 2. Stream valley in Driftless Area Ecoregion, showing 

typical combination of grassland/shrubland, wetland, and 

agriculture land covers. Buffer areas between streams and 

agricultural land varied throughout ecoregion. 

Figure 3. Example of farming up on plateau and in valley and, 

in between, forested hillside too steep to farm, in Driftless Area 

Ecoregion.

Figure 4. Example of agriculture land use in Driftless Area 

Ecoregion, including corn and hay production, as well as livestock 

grazing on pastureland.

Figure 5. Contour farming, an erosion-control management 

practice used in Driftless Area Ecoregion.

Historically, tallgrass prairies were the major vegetation 

type on the plateaus, and wet prairies were the major vegetation 

type in the valleys. Common prairie species in the ecoregion 

include little bluestem (Schizachyrium condensatum), Indiangrass 

(Sorghastrum nutans), and sideoats grama (Bouteloua 

curtipendula) (Wiken and others, 2011). The hardwood tree 

species are diverse and include white oak (Quercus alba), sugar 

maple (Acer saccharum), and river birch (Betula nigra) (Wiken 

and others, 2011). Land change in the mid-1800s occurred as 

European settlers altered the natural vegetation by clearing it 

for agricultural development (McCormick, 2011). The effects 

of this early land-cover/land-use change were apparent by the 

early 1900s, when extensive hillside erosion produced large 

amounts of sediment that accumulated in valleys and streams 

(McCormick, 2011). Few natural grasslands were present in 

the ecoregion during the study period, and fire suppression has 

allowed forests to move into some of the remaining grasslands 

(Wisconsin Department of Natural Resources, 2012). 

Agriculture, which occupies much of the upland areas 

and, to a lesser extent, the stream valleys, is now the dominant 

land cover in the ecoregion. Intensive row cropping of corn 

and soybeans is widespread. In addition to providing foodstuffs 

for market, these crops help support the livestock industry in 

the ecoregion, along with hay farming and pasture, which are 

also common agricultural land uses throughout the ecoregion 

(figs. 3, 4, 5). However, agricultural runoff and erosion from 

row cropping has affected the quality of streams and freshwater 

ecosystems in the ecoregion (McCormick, 2011).

The Driftless Area Ecoregion is a rural ecoregion with 

a few small towns and cities in the river valleys. The largest 

population centers in the ecoregion (2000 populations) are 

Dubuque, Iowa (89,143); Rochester, Minnesota (124,277); and 

La Crosse, Wisconsin (126,838) (U.S. Census Bureau, 2001). 

Metropolitan areas located outside of, but near to, the Driftless 

Area Ecoregion include (2000 populations) Minneapolis–Saint 

Paul, Minnesota (2,968,806), and Madison (426,526) and Eau 

Claire (148,337), Wisconsin (U.S. Census Bureau, 2001).
Chapter 4—Driftless Area Ecoregion 55

Figure 8. Normalized average net change in Driftless Area 

Ecoregion by time period for each land-cover class. Bars above 

zero axis represent net gain, whereas bars below zero represent 

net loss. Note that not all land-cover classes shown in explanation 

may be represented in figure. See appendix 3 for definitions of 

land-use and land-cover classifications.

Figure 6. Overall spatial change in Driftless Area Ecoregion (DA; 

darker bars) compared with that of all 17 Midwest–South Central 

United States ecoregions (lighter bars). Each horizontal set of 

bars shows proportions of ecoregion that changed during one, 

two, three, or four time periods; highest level of spatial change 

in Driftless Area Ecoregion (four time periods) labeled for clarity. 

See table 2 for years covered by each time period. See appendix 2 

for key to ecoregion abbreviations.

Figure 7. Estimates of land-cover change per time period, 

normalized to annual rates of change for all 17 Midwest–South 

Central United States ecoregions (gray bars). Estimates of change 

for Driftless Area Ecoregion are represented by red bars in each 

time period.

0 12 24 36

Area, as percent of ecoregion

Ecoregion 

DA

HELP

CCBP

SMNIDP

NCHF

BM

IRL

SEWTP

OH

EDP

ECBP

NMW

AV

MAP

NLF

SCP

OM

EXPLANATION

Change in one time period

Change in two time periods

Change in three time periods

Change in four time periods

Change in four time periods

0.5

0.0

1.0

1.5

2.5

3.0

2.0

3.5

1973 to 1980 1980 to 1986 1986 to 1992 1992 to 2000

Average annual change, as percent of ecoregion

Time period

−1

−0.5

0

0.5

1

1973–1980 1980–1986 

Time period

1986–1992 1992–2000 

Area changed, as percent of ecoregion 

Water

Developed

Mechanically disturbed

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Nonmechanically disturbed

Ice/Snow

EXPLANATION

LAND-USE/LAND-COVER CLASS

Contemporary Land-Cover Change

(1973 to 2000)

The overall spatial change (the percentage of land area 

that changed at least one time) in the Driftless Area Ecoregion 

between 1973 and 2000 is estimated at 1.8 percent (table 1). 

Compared to other Midwest–South Central United States 

ecoregions, change in the Driftless Area Ecoregion was 

the lowest overall (table 1; fig. 6): about 1.4 percent of the 

area changed only once during the study period, and about 

0.3 percent changed twice. The change per time period was 

relatively constant, at 0.5 percent of the ecoregion between 1973 

and 1986, and 0.6 percent in between 1986 and 2000 (table 2). 

When normalized to an annual rate of change to account for 

uneven time periods, the average rate for each time period was 

0.1 percent, ranging from 35 to 48 km2 per year (table 2; fig. 7).

Agriculture land cover experienced the greatest amount 

of net change between 1973 and 2000 (fig. 8), a 362 km2

decrease from 64.7 to 63.9 percent of the ecoregion, but it 

remained the predominant land cover throughout the 27-year 

study period (table 3). Forest was the second most predominant 

land cover throughout the study period, covering about 30.8 

percent of the land area, but it experienced essentially no net 

change, expanding into grassland/shrubland in some areas 

and being cleared for agriculture in other areas. The wetland 

and developed land-cover classes covered only between 1 and 

about 2 percent of the land area. All other land-cover classes 
56 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

each had 1 percent or less of the land area during the study 

period (table 3). Although few land-cover classes experienced 

much change, developed expanded by 34.3 percent from its 

estimated 1973 level, covering 1.3 percent of the ecoregion by 

2000. Grassland/shrubland experienced an even larger relative 

increase of 57.4 percent, but it covered only 0.8 percent of the 

ecoregion by 2000.

The leading land-cover changes between 1973 and 

2000 involved the conversion of agriculture to grassland/

shrubland (305 km2) and to developed (151 km2) (figs. 9, 10; 

table 4). These conversions accounted for about 43.7 percent 

of all change during the study period. Other sources of landcover change included the conversion of 118 km2 of wetland 

to water, as well as the 109 km2 increase in forest from 

grassland/shrubland. 

Although agriculture was still the predominant land cover 

in the ecoregion, this land-cover class lost some area to other 

land-cover classes. The most common conversion (agriculture 

to grassland/shrubland) may be attributed either to farmland 

abandonment or to enrollment in the Conservation Reserve 

Program (CRP). The CRP removed sensitive areas of farmland 

from production to reduce soil loss and agricultural runoff 

associated with fertilizers, thereby improving water quality 

and wildlife habitat (fig. 9).

Although the ecoregion remained predominantly rural, 

some suburban and exurban development did occur, much of it 

on agricultural land (fig. 10). The expansion of the nearby Eau 

Claire and Madison, Wisconsin, and Minneapolis–Saint Paul, 

Minnesota, metropolitan areas contributed to much of the 

development within the Driftless Area Ecoregion. 

Figure 10. Example of exurban development in Driftless Area 

Ecoregion.

Figure 9. Former agricultural land probably enrolled in 

Conservation Reserve Program (CRP), in Driftless Area Ecoregion.
Chapter 4—Driftless Area Ecoregion 57

Table 2. Raw estimates of change in Driftless Area Ecoregion land cover, computed for each of four 

time periods between 1973 and 2000, and associated error at 85-percent confidence level.

[Estimates of change per period normalized to annual rate of change for each time period]

Period Total change

(% of ecoregion)

Margin of 

error

(+/− %)

Lower 

bound

(%)

Upper bound

(%)

Standard 

error

(%)

Relative 

error

(%)

Average rate

(% per year)

Estimate of change, in percent stratum

1973–1980 0.5 0.2 0.4 0.7 0.1 22.2 0.1

1980–1986 0.5 0.2 0.2 0.7 0.1 31.6 0.1

1986–1992 0.6 0.2 0.4 0.8 0.2 26.3 0.1

1992–2000 0.6 0.2 0.4 0.8 0.1 21.5 0.1

Estimate of change, in square kilometers

1973–1980 248 81 167 329 55 22.2 35

1980–1986 216 101 116 317 68 31.6 36

1986–1992 288 112 176 399 76 26.3 48

1992–2000 293 93 200 386 63 21.5 37

Table 1. Percentage of Driftless Area Ecoregion land cover that 

changed at least one time during study period (1973–2000) and 

associated statistical error.

[Most sample pixels remained unchanged (98.2 percent), whereas 1.8 percent 

changed at least once throughout study period] 

Number

of

changes

Percent

of

ecoregion

Margin

of error

(+/− %)

Lower

bound

(%)

Upper

bound

(%)

Standard

error

(%)

Relative

error

(%)

1 1.4 0.5 0.9 1.9 0.3 24.2

2 0.3 0.2 0.2 0.5 0.1 32.9

3 0.0 0.0 0.0 0.1 0.0 51.8

4 0.0 0.0 0.0 0.0 0.0 64.8

Overall 

spatial 

change

1.8 0.5 1.2 2.3 0.4 20.7
58 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Table 3. Estimated area (and margin of error) of each land-cover class in Driftless Area Ecoregion, calculated five 

times between 1973 and 2000. See appendix 3 for definitions of land-cover classifications.

Water Developed

Mechanically 

disturbed

Mining Barren Forest Grassland/

Shrubland Agriculture Wetland

Nonmechanically 

disturbed

% +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/−

Area, in percent stratum

1973 0.9 0.6 1.0 0.4 0.0 0.0 0.1 0.0 0.0 0.0 30.8 3.9 0.5 0.2 64.7 4.3 2.1 0.6 0.0 0.0

1980 1.0 0.7 1.1 0.4 0.0 0.0 0.1 0.0 0.0 0.0 30.7 3.9 0.5 0.2 64.6 4.3 2.0 0.6 0.0 0.0

1986 1.0 0.6 1.2 0.4 0.0 0.0 0.1 0.0 0.0 0.0 30.8 3.9 0.6 0.3 64.4 4.3 2.0 0.6 0.0 0.0

1992 1.0 0.7 1.2 0.4 0.0 0.0 0.1 0.0 0.0 0.0 30.8 3.9 0.9 0.5 64.0 4.3 2.0 0.6 0.0 0.0

2000 1.0 0.6 1.3 0.5 0.0 0.0 0.1 0.0 0.0 0.0 30.8 3.9 0.8 0.5 63.9 4.3 2.0 0.6 0.0 0.0

Net

change 0.1 0.1 0.3 0.1 0.0 0.0 0.1 0.0 0.0 0.0 0.1 0.1 0.3 0.4 –0.8 0.5 –0.1 0.1 0.0 0.0

Gross

change 0.4 0.3 0.3 0.1 0.0 0.0 0.1 0.0 0.0 0.0 0.4 0.1 0.7 0.5 1.2 0.5 0.4 0.3 0.0 0.0

Area, in square kilometers

1973 428 267 466 181 4 4 30 11 2 2 14,639 1,841 242 97 30,782 2,070 997 289 0 0

1980 461 316 514 194 6 6 36 14 2 2 14,629 1,839 238 98 30,741 2,066 962 282 0 0

1986 452 296 549 205 3 2 37 14 2 2 14,639 1,837 295 147 30,639 2,062 974 285 0 0

1992 473 330 581 212 3 2 43 15 2 2 14,654 1,836 409 223 30,472 2,039 955 281 0 0

2000 464 306 626 223 4 4 54 22 2 2 14,670 1,838 381 226 30,421 2,068 967 282 0 0

Net

change 36 57 160 53 1 6 24 14 0 0 32 47 139 169 –362 217 –30 59 0 0

Gross

change 177 154 160 53 22 11 27 14 0 0 178 30 356 229 563 250 179 154 0 0
Chapter 4—Driftless Area Ecoregion 59

Table 4. Principal land-cover conversions in Driftless Area Ecoregion, showing amount of area changed (and margin of error, 

calculated at 85-percent confidence level) for each conversion during each of four time periods and also during overall study 

period. See appendix 3 for definitions of land-cover classifications.

[Values given for “other” class are combined totals of values for other land-cover classes not listed in that time period. Abbreviations: n/a, not applicable]

Period From class To class

Area 

changed

Margin

of error

Standard 

error Percent of 

ecoregion

Percent 

of all 

changes (km2) (+/− km2) (km2)

1973–1980 Wetland Water 58 62 42 0.1 23.4

Agriculture Developed 52 29 20 0.1 20.9

Grassland/Shrubland Forest 33 18 12 0.1 13.5

Forest Agriculture 32 17 11 0.1 13.0

Agriculture Grassland/Shrubland 27 13 9 0.1 10.9

Other Other 45 n/a n/a 0.1 18.3

Totals 248 0.5 100.0

1980–1986 Agriculture Grassland/Shrubland 84 88 60 0.2 38.8

Grassland/Shrubland Forest 30 14 10 0.1 14.0

Agriculture Developed 29 14 9 0.1 13.4

Water Wetland 21 24 16 0.0 9.5

Forest Agriculture 18 9 6 0.0 8.5

Other Other 34 n/a n/a 0.1 15.8

Totals 216 0.5 100.0

1986–1992 Agriculture Grassland/Shrubland 139 103 70 0.3 48.4

Wetland Water 35 39 27 0.1 12.3

Agriculture Developed 29 13 9 0.1 10.2

Grassland/Shrubland Forest 26 12 8 0.1 9.0

Water Wetland 16 11 7 0.0 5.5

Other Other 42 n/a n/a 0.1 14.7

Totals 288 0.6 100.0

1992–2000 Grassland/Shrubland Agriculture 64 70 47 0.1 21.7

Agriculture Grassland/Shrubland 55 39 26 0.1 18.7

Agriculture Developed 41 18 13 0.1 14.1

Water Wetland 25 27 18 0.1 8.6

Agriculture Forest 25 14 9 0.1 8.5

Other Other 83 n/a n/a 0.2 28.4

Totals 293 0.6 100.0

1973–2000

(overall)

Agriculture Grassland/Shrubland 305 203 138 0.6 29.2

Agriculture Developed 151 52 35 0.3 14.5

Wetland Water 118 103 70 0.2 11.2

Grassland/Shrubland Forest 109 48 32 0.2 10.5

Water Wetland 88 66 45 0.2 8.4

Other Other 274 n/a n/a 0.6 26.3

Totals 1,045 2.2 100.0
60 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

References Cited

Driftless Area Initiative, 2012, Defining the “Driftless Area”: 

Driftless Area Initiative Web site, accessed November 7, 

2012, at http://www.driftlessareainitiative.org/aboutus/

defining_driftless.cfm. 

McCormick, T.J., 2011, The Driftless Area—Coldwater 

trout streams call attention to the ecological health of 

southeastern Minnesota: Minnesota Department of Natural 

Resources, accessed March 15, 2011, at http://www.dnr.

state.mn.us/volunteer/marapr07/driftless.html.

Omernik, J.M., 1987, Ecoregions of the conterminous United 

States: Annals of the Association of American Geographers, 

v. 77, no. 1, p. 118–125.

PRISM Climate Group, 2006, Precipitation—Annual 

climatology (1971–2000): Corvallis, Oregon State 

University, The PRISM Climate Group database, accessed 

November 5, 2012, at http://www.prism.oregonstate.edu/.

U.S. Census Bureau, 2001, Metropolitan areas ranked by 

population—2000: U.S. Census Bureau database, accessed 

March 25, 2011, at http://www.census.gov/population/

www/cen2000/briefs/phc-t3/tables/tab03.pdf.

Vogelmann, J.E., Howard, S.M., Yang, L., Larson, C.R., 

Wylie, B.K., and van Driel, N., 2001, Completion of the 

1990s National Land Cover Data Set for the conterminous 

United States from Landsat Thematic Mapper data and 

ancillary data sources: Photogrammetric Engineering & 

Remote Sensing, v. 67, p. 650–662.

Wiken, E., Jiménez Nava, F., and Griffith, G., 2011, North 

American terrestrial ecoregions—Level III: Montreal, 

Canada, Commission for Environmental Cooperation, 149 

p., accessed November 5, 2012, at http://www.cec.org/

Storage/133/15860_QA07.30-32_NP_NA_Terrestrial_

Ecoregions_Level_3_Final-2june11.pdf.

Wisconsin Department of Natural Resources, 2012, 

Rapid ecological assessment for Driftless Area study 

streams—A rapid ecological assessment focusing on rare 

plants, selected rare animals, and high-quality natural 

communities: Wisconsin Department of Natural Resources, 

Bureau of Endangered Resources Natural Heritage 

Inventory Program, accessed November 7, 2012, at http://

dnr.wi.gov/files/PDF/pubs/er/ER0836_ext.pdf.
Chapter 5

Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000 

Edited by Roger F. Auch and Krista A. Karstensen 

U.S. Geological Survey Professional Paper 1794–C, 2015

Southern Michigan/Northern Indiana Drift Plains Ecoregion

By Steven Kambly

87° 86° 85° 84° 83°

44°

43°

42°

41° Eastern

Corn Belt Plains

Huron/

Erie

Lake Plains

HELP

Huron/Erie

Lake Plains

Northern

Lakes and Forests

Central

Corn Belt

Plains

NCHF

EGLHL

LAKE

MICHIGAN

LAKE ERIE

LAKE HURON

CANADA

IN

MI

OH

Southern

Michigan/Northern

Indiana Drift Plains

Ecoregion

0 50 100 MILES

0 50 100 KILOMETERS

Ecoregion boundary

Sample block (10 x 10 km)

Land-use/land-cover class

Water

Developed

Transitional

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Ice/Snow

EXPLANATION

MICHIGAN

INDIANA OHIO

“THUMB”

REGION

Saginaw

South Bend

Flint

Lansing

Grand Rapids

Holland

LAKE MICHIGAN

LAKE HURON

Holt Detroit

LAKE

ERIE

Ecoregion Description 

The Southern Michigan/Northern Indiana Drift Plains 

Ecoregion covers about 73,987 km2 (28,566 mi2) from 

northern Indiana into Michigan’s lower peninsula and 

“Thumb” region (fig. 1) (Omernik, 1987; Wiken and others, 

2011). The Huron/Erie Lake Plains Ecoregion lies both north 

and south of the eastern part of the ecoregion; the Eastern 

Corn Belt Plains and Central Corn Belt Plains Ecoregions lie 

to the south; and the Northern Lakes and Forests Ecoregion 

and a small part of the North Central Hardwood Forests 

Figure 1. Map of Southern 

Michigan/Northern Indiana 

Drift Plains Ecoregion and 

surrounding ecoregions, 

showing land-use/landcover classes from 1992 

National Land Cover Dataset 

(Vogelmann and others, 

2001); note that not all landuse/land-cover classes 

shown in explanation may 

be depicted on map; note 

also that, for this “Status 

and Trends of Land Change” 

study, transitional land-cover 

class was subdivided into 

mechanically disturbed and 

nonmechanically disturbed 

classes. Squares indicate 

locations of 10 x 10 km 

sample blocks analyzed in 

study. Index map shows 

locations of geographic 

features mentioned in text. 

Abbreviations for Midwest–

South Central United States 

ecoregions are listed in 

appendix 2. See appendix 3 

for definitions of land-use/

land-cover classifications.

Ecoregion lie to the north. It has a humid continental climate, 

with average annual precipitation levels ranging from 750 

to 990 mm (30 to 39 in.), and it typically is characterized by 

warm summers and severe winters (Wiken and others, 2011). 

Average annual minimum and maximum temperatures are 

–13°C and 29.5°C, respectively, and the annual frost-free 

period ranges from 140 to 200 days (Wiken and others, 2011).

The Southern Michigan/Northern Indiana Drift Plains 

Ecoregion is situated between highly productive agricultural 
62 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

land to the south and east and large expanses of forests, lakes, 

and wetlands to the north. The landscape of the ecoregion 

largely is the result of glaciation, and many glacial landforms 

(including till plains, morainal hills, kames, drumlins, and 

kettles, as well as paleo–beach ridges and relict dunes) define 

its topography (U.S. Environmental Protection Agency, 

2002). Soils are mostly Alfisols, which are highly suitable for 

agriculture.

Corn is the most extensively grown crop, followed by 

soybeans, hay, wheat, dry beans, miscellaneous fruits and 

vegetables, sugar beets, and potatoes. Corn, soybeans, wheat, 

and hay are cultivated throughout the ecoregion; sugar beets 

and dry beans are cultivated primarily in Michigan’s “Thumb” 

region and the lowlands around Saginaw, Michigan (figs.2,3). 

Livestock operations include dairying, beef production, and 

hog, chicken, and turkey farming. Overall, cropland and 

pastureland constitute most of the landscape in the ecoregion. 

Forests, which make up about one-quarter of the 

ecoregion, largely are deciduous, with four main types: 

oak-hickory (Quercus spp. and Carya spp., respectively), 

Figure 2. Soybeans, major crop in Southern Michigan/Northern 

Indiana Drift Plains Ecoregion.

Figure 3. Corn field with “developable land” sign, near Holland, 

Michigan.

Figure 4. Former automobile-manufacturing site that has 

become vacant land, in Flint, Michigan.

Figure 5. New subdivision near Holt, Michigan.

American elm–ash–maple (Ulmus americana, Fraxinus spp., 

and Acer spp., respectively), aspen-birch (Populus spp. and 

Betula spp., respectively), and maple–American beech–birch 

(Acer spp., Fagus grandifolia, and Betula spp., respectively). 

In the ecoregion, white pine (Pinus strobus) is common among 

the conifers, although conifers are less common than the 

deciduous species (U.S. Environmental Protection Agency, 

2007). Primarily because of the large-scale clearing of forests 

for farmland in the latter half of the 1800s, the extent of forest 

land has decreased substantially from pre–European-settlement 

levels (Rudy and others, 2008). Furthermore, urbanization in 

both rural and suburban areas has increased, which may have 

increased forest fragmentation in the ecoregion.

The cities of South Bend, Indiana, and Detroit, Flint, 

Lansing, and Grand Rapids, Michigan, contributed to the 

expansion of developed land throughout the 20th century, 

as new suburban and exurban development occurred in the 

outlying regions of these metropolitan areas. This growth 

was the leading cause of decreases in farmland, forests, and 

wetlands in the ecoregion (figs. 3,4,5).
Chapter 5—Southern Michigan/Northern Indiana Drift Plains Ecoregion 63

Contemporary Land-Cover Change 

(1973 to 2000)

The overall spatial change (the percentage of land area 

that changed at least one time) in the Southern Michigan/

Northern Indiana Drift Plains Ecoregion between 1973 

and 2000 is estimated at 4.2 percent. Compared to other 

Midwest–South Central United States ecoregions, change 

in the Southern Michigan/Northern Indiana Drift Plains 

Ecoregion was relatively low (table 1; fig. 6): an estimated 

3.5 percent of the ecoregion changed in only one time period, 

whereas 0.6 and 0.1 percent of the ecoregion changed in two 

and three time periods, respectively (table 1). The estimated 

change per time period increased steadily from 0.8 percent of 

the ecoregion between 1973 and 1980 to 1.6 percent between 

1992 and 2000. The normalized estimated annual rates of 

change also indicate a consistent increase between 1973 and 

1992 (from 89 to 171 km2 per year), with a slight decrease to 

152 km2 per year between 1992 and 2000 (table 2; fig. 7). 

Only two land-cover classes, developed and agriculture, 

had an estimated net change in area of greater than one 

percent during the study period (table 3). Developed 

increased by 24.4 percent (1,415 km2), whereas agriculture 

decreased by 3.1 percent (1,231 km2) (table 3). Most of the 

change in both land-cover classes resulted from conversion 

of farmland to developed land. In fact, nearly all the 

conversions of agriculture were to developed, except for 

small amounts that converted to grassland/shrubland or 

forest, which had net decreases of 8 percent and 1 percent, 

respectively, from their 1973 estimated levels.

The most common change during the study period was 

the conversion of agriculture to developed (fig. 8), which 

accounted for 25.7 percent of all change detected (table 4). 

Overall, 945 km2 of farmland converted to developed land, 

with almost half of this conversion (420 km2) occurring 

between 1992 and 2000. Forest also converted to developed, 

which was the fifth leading conversion overall; an estimated 

288 km2 changed to developed between 1973 and 2000. 

The second leading conversion throughout the study period 

was from grassland/shrubland to forest. Generally, this 

conversion was an intermediate change, as agriculture 

initially converted to grassland/shrubland (the fourth leading 

conversion) before reverting to forest. During the first and 

last time periods, areas of farmland that converted directly 

to forest ranked among the top five types of changes (table 

4). Between 1973 and 2000, the amount of farmland that 

converted to grassland/shrubland was estimated at 342 km2

(table 4), whereas the amount of farmland that converted to 

forest was estimated at 223 km2 (these amounts are included 

as part of the “Other” change class in table 4).

Developed increased more than any other land-cover 

class during the 27-year study period, from an estimated 

7.8 to 9.8 percent of the ecoregion. Increases in developed 

0 12 24 36

Area, as percent of ecoregion

Ecoregion 

DA

HELP

CCBP

SMNIDP

NCHF

BM

IRL

SEWTP

OH

EDP

ECBP

NMW

AV

MAP

NLF

SCP

OM

EXPLANATION

Change in one time period

Change in two time periods

Change in three time periods

Change in four time periods

Change in four time periods

0.5

0.0

1.0

1.5

2.5

3.0

2.0

3.5

1973 to 1980 1980 to 1986 1986 to 1992 1992 to 2000

Average annual change, as percent of ecoregion

Time period

Figure 6. Overall spatial change in Southern Michigan/Northern

Indiana Drift Plains Ecoregion (SMNIDP; darker bars) compared 

with that of all 17 Midwest–South Central United States 

ecoregions (lighter bars). Each horizontal set of bars shows 

proportions of ecoregion that changed during one, two, three, 

or four time periods; highest level of spatial change in Southern 

Michigan/Northern Indiana Drift Plains Ecoregion (four time 

periods) labeled for clarity. See table 2 for years covered by each 

time period. See appendix 2 for key to ecoregion abbreviations.

Figure 7. Estimates of land-cover change per time period,

normalized to annual rates of change for all 17 Midwest–South 

Central United States ecoregions (gray bars). Estimates of 

change for Southern Michigan/Northern Indiana Drift Plains 

Ecoregion are represented by red bars in each time period.
64 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

−1

−0.5

0

0.5

1

1973–1980 1980–1986 

Time period

1986–1992 1992–2000 

Area changed, as percent of ecoregion 

Water

Developed

Mechanically disturbed

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Nonmechanically disturbed

Ice/Snow

EXPLANATION

LAND-USE/LAND-COVER CLASS

Figure 8. Normalized average 

net change in Southern Michigan/

Northern Indiana Drift Plains 

Ecoregion by time period for each 

land-cover class. Bars above zero 

axis represent net gain, whereas 

bars below zero represent net 

loss. Note that not all land-cover 

classes shown in explanation 

may be represented in figure. See 

appendix 3 for definitions of landuse and land-cover classifications.

occurred most notably in the suburban and exurban counties 

that surround the cities of Detroit, Flint, Lansing, and Grand 

Rapids, Michigan. In general, suburban and exurban growth 

was due to large-scale population shifts from city centers 

and older suburbs to outlying counties. The building of new 

communities—characterized by lower density development 

and following a state-wide trend toward smaller household 

size—increased the amount of developed land per capita 

(Michigan Land Use Leadership Council, 2003) and resulted 

in a decrease in farmland and more natural land covers.
Chapter 5—Southern Michigan/Northern Indiana Drift Plains Ecoregion 65

Table 1. Percentage of Southern Michigan/Northern Indiana Drift 

Plains Ecoregion land cover that changed at least one time during 

study period (1973–2000) and associated statistical error.

[Most sample pixels remained unchanged (95.8 percent), whereas 4.2 percent 

changed at least once throughout study period]

Number

of

changes

Percent

of

ecoregion

Margin

of error

(+/− %)

Lower

bound

(%)

Upper

bound

(%)

Standard

error

(%)

Relative

error

(%)

1 3.5 0.8 2.7 4.3 0.6 16.1

2 0.6 0.3 0.4 0.9 0.2 28.7

3 0.1 0.1 0.0 0.2 0.1 59.7

4 0.0 0.0 0.0 0.0 0.0 54.6

Overall 

spatial 

change

4.2 0.9 3.3 5.1 0.6 14.9

Table 2. Raw estimates of change in Southern Michigan/Northern Indiana Drift Plains Ecoregion land 

cover, computed for each of four time periods between 1973 and 2000, and associated error at 85-percent 

confidence level.

[Estimates of change per period normalized to annual rate of change for each period]

Period Total change

(% of ecoregion)

Margin of 

error

(+/− %)

Lower 

bound

(%)

Upper bound

(%)

Standard 

error

(%)

Relative 

error

(%)

Average rate

(% per year)

Estimate of change, in percent stratum

1973–1980 0.8 0.2 0.7 1.0 0.1 14.9 0.1

1980–1986 1.1 0.3 0.8 1.4 0.2 17.6 0.2

1986–1992 1.4 0.4 1.0 1.8 0.3 19.7 0.2

1992–2000 1.6 0.5 1.2 2.1 0.3 19.3 0.2

Estimate of change, in square kilometers

1973–1980 624 137 487 760 93 14.9 89

1980–1986 819 212 607 1,031 144 17.6 136

1986–1992 1,025 297 728 1,321 201 19.7 171

1992–2000 1,216 345 871 1,561 234 19.3 152
66 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Table 3. Estimated area (and margin of error) of each land-cover class in Southern Michigan/Northern Indiana Drift Plains Ecoregion, 

calculated five times between 1973 and 2000. See appendix 3 for definitions of land-cover classifications.

Water Developed

Mechanically 

disturbed

Mining Barren Forest Grassland/

Shrubland Agriculture Wetland

Nonmechanically 

disturbed

% +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/−

Area, in percent stratum

1973 4.1 3.9 7.8 3.7 0.0 0.0 0.1 0.0 0.0 0.0 24.4 4.8 1.3 0.4 54.2 6.0 7.9 1.6 0.0 0.0

1980 4.2 3.9 8.2 3.8 0.0 0.0 0.1 0.0 0.0 0.0 24.4 4.8 1.3 0.3 54.0 6.0 7.9 1.6 0.0 0.0

1986 4.2 3.9 8.5 3.9 0.1 0.1 0.1 0.0 0.0 0.0 24.3 4.7 1.3 0.3 53.6 6.1 7.9 1.6 0.0 0.0

1992 4.2 3.9 8.9 4.0 0.2 0.1 0.2 0.1 0.0 0.0 24.1 4.7 1.3 0.3 53.3 6.1 7.8 1.6 0.0 0.0

2000 4.2 3.9 9.8 4.3 0.1 0.1 0.2 0.1 0.0 0.0 24.2 4.7 1.2 0.3 52.6 6.2 7.8 1.6 0.0 0.0

Net

change 0.1 0.0 1.9 0.7 0.1 0.1 0.1 0.0 0.0 0.0 –0.2 0.4 –0.1 0.2 –1.7 0.6 –0.1 0.1 0.0 0.0

Gross

change 0.1 0.0 1.9 0.7 0.4 0.2 0.1 0.1 0.0 0.0 1.3 0.4 0.8 0.3 2.1 0.6 0.2 0.1 0.0 0.0

Area, in square kilometers

1973 3,069 2,879 5,801 2,765 30 32 81 29 0.3 0.4 18,063 3,557 957 261 40,127 4,462 5,858 1,205 0 0

1980 3,077 2,879 6,048 2,802 19 15 95 32 0.3 0.4 18,044 3,549 936 258 39,927 4,462 5,842 1,203 0 0

1986 3,096 2,877 6,325 2,887 89 69 102 36 0.3 0.4 17,964 3,508 936 244 39,658 4,497 5,817 1,206 0 0

1992 3,103 2,878 6,610 2,973 112 74 126 51 0.3 0.4 17,855 3,500 964 226 39,416 4,536 5,801 1,211 0 0

2000 3,121 2,877 7,216 3,194 69 66 145 57 0.3 0.4 17,886 3,501 881 208 38,896 4,623 5,773 1,206 0 0

Net

change 52 26 1,415 522 39 75 64 36 0.0 0.0 –177 283 –77 145 –1,231 475 –86 41 0 0

Gross

change 79 27 1,415 522 267 153 105 39 0.0 0.0 990 267 586 186 1,539 450 138 48 0 0
Chapter 5—Southern Michigan/Northern Indiana Drift Plains Ecoregion 67

Table 4. Principal land-cover conversions in Southern Michigan/Northern Indiana Drift Plains Ecoregion, showing amount of area 

changed (and margin of error, calculated at 85-percent confidence level) for each conversion during each of four time periods and 

also during overall study period. See appendix 3 for definitions of land-cover classifications.

[Values given for “other” class are combined totals of values for other land-cover classes not listed in that time period. Abbreviations: n/a, not applicable]

Period From class To class

Area 

changed

Margin of 

error

Standard 

error Percent of 

ecoregion

Percent of all 

changes (km2) (+/− km2) (km2)

1973–1980 Agriculture Developed 145 49 34 0.2 23.3

Grassland/Shrubland Forest 85 52 36 0.1 13.6

Forest Developed 83 52 35 0.1 13.3

Forest Agriculture 65 23 16 0.1 10.4

Agriculture Forest 61 40 27 0.1 9.7

Other Other 185 n/a n/a 0.3 29.7

Totals 624 0.8 100

1980–1986 Agriculture Developed 207 114 77.6 0.3 25.3

Agriculture Grassland/Shrubland 111 64 43.7 0.1 13.5

Grassland/Shrubland Forest 107 70 47.8 0.1 13.0

Forest Agriculture 92 52 35.7 0.1 11.3

Forest Mechanically disturbed 84 66 44.7 0.1 10.3

Other Other 217 n/a n/a 0.3 26.5

Totals 819 1.1 100

1986–1992 Agriculture Developed 173 104 70.4 0.2 16.9

Forest Agriculture 134 75 50.6 0.2 13.1

Agriculture Grassland/Shrubland 121 54 36.9 0.2 11.8

Forest Mechanically disturbed 104 73 49.4 0.1 10.1

Grassland/Shrubland Forest 100 60 40.9 0.1 9.8

Other Other 393 n/a n/a 0.5 38.4

Totals 1,025 1.4 100

1992–2000 Agriculture Developed 420 198 134.2 0.6 34.5

Grassland/Shrubland Forest 153 91 61.7 0.2 12.6

Forest Developed 100 60 40.6 0.1 8.2

Agriculture Forest 74 39 26.4 0.1 6.1

Forest Mechanically disturbed 63 66 44.6 0.1 5.2

Other Other 406 n/a n/a 0.5 33.4

Totals 1,216 1.6 100

1973–2000

(overall)

Agriculture Developed 945 387 263.2 1.3 25.7

Grassland/Shrubland Forest 444 218 148.0 0.6 12.1

Forest Agriculture 354 145 98.2 0.5 9.6

Agriculture Grassland/Shrubland 342 161 109.6 0.5 9.3

Forest Developed 288 155 105.4 0.4 7.8

Other Other 1,310 n/a n/a 1.8 35.6

Totals 3,683 5.0 100
68 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

References Cited

Michigan Land Use Leadership Council, 2003, Michigan’s 

land, Michigan’s future—Final report of the Michigan Land 

Use Leadership Council: Michigan Land Use Leadership 

Council, accessed August 15, 2010, at http://michigan.gov/

documents/MLULC_FINAL_REPORT_0803_77503_7.pdf.

Omernik, J.M., 1987, Ecoregions of the conterminous United 

States: Annals of the Association of American Geographers, 

v. 77, no. 1, p. 118–125.

Rudy, A.P., Harris, C.K., Thomas, B.J., Worosz, M.R., Kaplan, 

S.S.K., and O’Donnell, E.C., 2008, The political ecology of 

southwest Michigan agriculture, 1837–2000, in Redman, C.L., 

and Foster, D.R., eds., Agrarian landscapes in transition—

Comparisons of long-term ecological and cultural change: 

New York, Oxford University Press, Inc., p. 152–205.

U.S. Environmental Protection Agency, 2002, Primary 

distinguishing characteristics of Level III ecoregions of the 

continental United States: U.S. Environmental Protection 

Agency, 19 p., accessed August 15, 2010, at ftp://ftp.epa.gov/

wed/ecoregions/us/Eco_Level_III_descriptions.doc.

U.S. Environmental Protection Agency, 2007, Michigan level 

III and IV ecoregion descriptions—Mapping issues [draft]: 

U.S. Environmental Protection Agency, 28 p., accessed 

January 8, 2013, at ftp://ftp.epa.gov/wed/ecoregions/mi/

MI_DRAFT_Desc-Issues12-27-07.pdf.

Vogelmann, J.E., Howard, S.M., Yang, L., Larson, C.R., 

Wylie, B.K., and van Driel, N., 2001, Completion of the 

1990s National Land Cover Data Set for the conterminous 

United States from Landsat Thematic Mapper data and 

ancillary data sources: Photogrammetric Engineering & 

Remote Sensing, v. 67, p. 650–662.

Wiken, E., Jiménez Nava, F., and Griffith, G., 2011, North 

American terrestrial ecoregions—Level III: Montreal, 

Canada, Commission for Environmental Cooperation, 

149 p., accessed November 5, 2012, at http://www.cec.

org/Storage/133/15860_QA07.30-32_NP_NA_Terrestrial_

Ecoregions_Level_3_Final-2june11.pdf.
Chapter 6

Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000 

Edited by Roger F. Auch and Krista A. Karstensen 

U.S. Geological Survey Professional Paper 1794–C, 2015

Erie Drift Plains Ecoregion 

By Janis L. Taylor

Ecoregion Description 

The Erie Drift Plains Ecoregion 

covers about 30,622 km2 (11,820 mi2), 

mainly in northeastern Ohio but 

also in the northwestern corner of 

Pennsylvania and the southwestern 

corner of New York (fig. 1). The 

ecoregion is bordered by the Northern 

Appalachian Plateau and Uplands, 

North Central Appalachians, Western 

Allegheny Plateau, and Eastern Corn 

Belt Plains Ecoregions, as well as by 

a long, narrow strip of the Eastern 

Great Lakes and Hudson Lowlands 

Ecoregion, which parallels the 

shoreline of Lake Erie and separates 

the lake from the northwestern part of 

the Erie Drift Plains Ecoregion.

The Allegheny Mountains, part 

of the Appalachian Mountains system, 

lie to the south and east of the Erie 

Drift Plains Ecoregion, and fertile, 

rolling plains lie to the west. Glacially 

derived features, which are common 

in the ecoregion, include low round 

hills, scattered end moraines, kettles, 

and wetlands (Omernik, 1987; Wiken 

and others, 2011). Maple, beech, and 

birch (Acer spp., Fagus grandifolia, 

and Betula spp., respectively) forests 

once covered the Erie Drift Plains 

Ecoregion, but as human populations 

increased in the eastern United States 

throughout the 19th century, much of 

the forest was cleared for agricultural 

and other uses. Today (2014), the 

ecoregion is a mix of agricultural, 

forested, and developed land (fig. 2). 

In 1827, the Ohio & Erie Canal 

connected the Ohio River to Lake Erie 

through the Cuyahoga River valley and 

Cleveland, Ohio. The canal stimulated 

growth in population, agriculture, 

and industry throughout Ohio. When 

Figure 1. Map of Erie Drift Plains Ecoregion and surrounding ecoregions, showing landuse/land-cover classes from 1992 National Land Cover Dataset (Vogelmann and others, 2001); 

note that not all land-use/land-cover classes shown in explanation may be depicted on map; 

note also that, for this “Status and Trends of Land Change” study, transitional land-cover 

class was subdivided into mechanically disturbed and nonmechanically disturbed classes. 

Squares indicate locations of 10 x 10 km sample blocks analyzed in study. Index map shows 

locations of geographic features mentioned in text. Abbreviations for Midwest–South Central 

United States ecoregions are listed in appendix 2. Also shown are parts of four Eastern 

United States ecoregions: Eastern Great Lakes and Hudson Lowlands (EGLHL), Northern 

Appalachian Plateau and Uplands (NAPU), North Central Appalachians (NCA), and Western 

Allegheny Plateau. See appendix 3 for definitions of land-use/land-cover classifications.

82° 81° 80° 79°

42°

41°

40°

Western

Allegheny Plateau

ECBP

CA

CA

RV

NCA

EGLHL

HELP

NAPU

LAKE

ERIE

CANADA

0 50 100 MILES

0 50 100 KILOMETERS

Ecoregion boundary

Sample block (10 x 10 km)

Land-use/land-cover class

Water

Developed

Transitional

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Ice/Snow

EXPLANATION

PA

OH

NY

Erie Drift Plains

Ecoregion

OHIO

WEST

VIRGINIA

PENNSYLVANIA

C A N A D A

NY

Burton

Mansfield

Canton Cuyahoga River

Sharon

Meadville

Cleveland

Jamestown

North Royalton

Brunswick

Hartville

Youngstown

O h i o

R i v e r

L A K E E R I E

Cleveland Heights

Strongsville

A L L E G H E N Y M O U N T A I N S

Ohio & Eri e Cana l

Garfield Heights

Maple Heights

Akron

Shaker Heights
70 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Figure 2. Examples of (A) agriculture, (B) forest, and (C) 

developed land-cover classes in Erie Drift Plains Ecoregion.

Figure 3. Agricultural field with newly emerged vegetable crop, 

near Hartville, Ohio.

first developed, this transportation system provided farmers a 

means to move their agricultural products to, and to acquire 

other products from, urban markets in the eastern United 

States. In 1861, the railroad replaced the canal as a major 

transportation system. Today (2014), the canal is maintained 

as a water supply for local industries, and a recreational trail 

system runs along parts of it. 

The Cuyahoga River drains a watershed of 2,103 km2

in northeastern Ohio; most of this watershed is in the Erie 

Drift Plains Ecoregion. From its headwaters near Burton, 

Ohio, the Cuyahoga River flows 161 km southwest and then 

north before entering Lake Erie at Cleveland, Ohio. This 

watershed provides fresh water for more than 15 percent of 

Ohio’s population (1.6 million people) (U.S. Environmental 

Protection Agency, 2013). In the late 1960s, the Cuyahoga 

River was considered the most polluted river in the nation—a 

symbol of industrial neglect of the environment. In 1969, 

the river became infamous when kerosene-laden oil from 

industrial spills, which was floating on the river, caught fire. 

This fire spurred efforts to develop clean-water legislation, 

resulting in the Environmental Protection Act of 1970 and 

the Clean Water Act of 1972. Today, the Cuyahoga River is 

designated as one of the Environmental Protection Agency’s 

American Heritage Rivers (Cuyahoga American Heritage 

River Program, 2001).

Transportation improvements in the Erie Drift Plains 

Ecoregion have supported a diverse economy, with strengths 

in manufacturing and agriculture. Major crops grown in the 

ecoregion include corn, soybeans, wheat, and oats (Woods 

and others, 1999), as well as market produce such as sweet 

corn, sweet peppers, pumpkins, onions, mustard greens, kale, 

and herbs (fig. 3). Beef production and dairy farming are 

common in rural areas. Lake Erie has a moderating effect on 

air temperatures, and vineyards and wineries line its shore 

(U.S. Department of Agriculture, 2012). In addition, apple and 

peach orchards, as well as maple-sugar-refining operations, 

thrive in this area. All contribute to the diversity of agricultural 

goods produced in the ecoregion. 

The major urban areas in or near the ecoregion are 

Cleveland, Akron, Mansfield, Youngstown, and Canton, 

Ohio; Sharon and Meadville, Pennsylvania; and Jamestown, 

New York. Cleveland, the second largest city and the leading 

industrial city in Ohio, sits just north of the ecoregion. The 

location of Cleveland on the shores of Lake Erie accounts 

for its success as a transportation, industrial, and commercial 

center, and the city is at the center of a very large metropolitan 

statistical area that encompasses multiple counties. Although 

Cleveland is not located in the Erie Drift Plains Ecoregion, 

most of its growing suburbs are; these include Maple Heights, 

Garfield Heights, Shaker Heights, Cleveland Heights, North 

Royalton, Strongsville, and Brunswick, Ohio (fig. 4).

A

B

C
Chapter 6—Erie Drift Plains Ecoregion 71

Figure 4. New urban development, located between Cleveland 

and Akron, Ohio.

Figure 5. Overall spatial change in Erie Drift Plains Ecoregion 

(EDP; darker bars) compared with that of all 17 Midwest–South 

Central United States ecoregions (lighter bars). Each horizontal set 

of bars shows proportions of ecoregion that changed during one, 

two, three, or four time periods; highest level of spatial change in 

Erie Drift Plains Ecoregion (four time periods) labeled for clarity. 

See table 2 for years covered by each time period. See appendix 2 

for key to ecoregion abbreviations.

Figure 6. Estimates of land-cover change per time period, 

normalized to annual rates of change for all 17 Midwest–South 

Central United States ecoregions (gray bars). Estimates of change 

for Erie Drift Plains Ecoregion are represented by red bars in each 

time period.

0 12 24 36

Area, as percent of ecoregion

Ecoregion 

DA

HELP

CCBP

SMNIDP

NCHF

BM

IRL

SEWTP

OH

EDP

ECBP

NMW

AV

MAP

NLF

SCP

OM

EXPLANATION

Change in one time period

Change in two time periods

Change in three time periods

Change in four time periods

Change in four time periods

0.5

0.0

1.0

1.5

2.5

3.0

2.0

3.5

1973 to 1980 1980 to 1986 1986 to 1992 1992 to 2000

Average annual change, as percent of ecoregion

Time period

Contemporary Land-Cover Change 

(1973 to 2000)

The overall spatial change (the percentage of land 

area that changed at least one time) in the Erie Drift Plains 

Ecoregion between 1973 and 2000 is estimated at 6.1 percent 

(1,860 km2) (table 1). Compared to other Midwest–South 

Central United States ecoregions, change in the Erie Drift 

Plains Ecoregion was moderate (table 1; fig. 5): about 4.9 

percent of the area changed in one time period, and 1.1 percent 

changed in two time periods (table 1). Total change in each 

time period ranged from 1.6 percent (477 km2) between 1973 

and 1980 to 2.2 percent (677 km2) between 1986 and 1992 

(table 2). After normalizing change per period to an annual 

rate to account for uneven time periods, change ranged from 

a low of 0.2 percent (68 km2) per year in the periods between 

1973 and 1980 and between 1992 and 2000 to a high of 0.4 

percent (113 km2) per year in the period between 1986 and 

1992 (table 2; fig. 6).

Forest, agriculture, and developed land-cover classes 

accounted for about 94.5 percent (28,970 km2) of the 

ecoregion area during the 27-year study period. The extent of 

forest decreased by about 2.0 percent (209 km2), from 37.5 

percent (11,491 km2) in 1973 to 36.8 percent (11,282 km2) 

in 2000. Agriculture decreased by 5.3 percent (768 km2), 

from 47.6 percent (14,562 km2) in 1973 to 45.0 percent 

(13,794km2) in 2000. Developed changed the most during 

the study period, with an increase of 33.9 percent (986 km2), 

from 9.5 percent (2,908 km2) in 1973 to 12.7 percent (3,894 

km2) in 2000 (table 3; fig. 7).

Overall, agriculture and forest land-cover conversions 

were the two most common conversions during the study 

period. An estimated 3.0 percent (925 km2) of either agriculture 

or forest that was mapped in 1973 had converted to developed 

by 2000, with forest providing most of this conversion in the 

first time period (1973–1980) and then agriculture losing more 
72 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

land in the last three time periods (1980–1986, 1986–1992, and 

1992–2000) (table 4). This unidirectional land-cover change to 

developed was driven by increases in population in the counties 

that lie along major highways. The third most common landcover conversion was from grassland/shrubland to forest (215 

km2) (table 4). This type of conversion may indicate agricultural 

abandonment in the past, as grassland/shrubland often results 

when agricultural land is idled, and then, commonly, trees 

eventually occupy these grassland/shrubland areas.

On the basis of interpretation of 30 sample blocks in the 

ecoregion, the highest rates of change were determined in the 

sample blocks in the urban corridor along major highways 

between Cleveland, Akron, and Youngstown (fig. 8). Generally 

speaking, the sample blocks that were adjacent to previously 

developed areas were changing the fastest. The surrounding areas 

were a combination of agricultural fields and forested lands; 

change was minimal within these areas during the study period.

−2

−1

0

1

2

1973–1980 1980–1986 

Time period

1986–1992 1992–2000 

Area changed, as percent of ecoregion 

Water

Developed

Mechanically disturbed

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Nonmechanically disturbed

Ice/Snow

EXPLANATION

LAND-USE/LAND-COVER CLASS

Figure 7. Normalized average net 

change in Erie Drift Plains Ecoregion by 

time period for each land-cover class. 

Bars above zero axis represent net gain, 

whereas bars below zero represent net 

loss. Note that not all land-cover classes 

shown in explanation may be represented 

in figure. See appendix 3 for definitions of 

land-use and land-cover classifications.
Chapter 6—Erie Drift Plains Ecoregion 73

Figure 8. Map of Erie Drift Plains Ecoregion and surrounding ecoregions, showing land-use/land-cover classes from 

1992 National Land Cover Dataset (Vogelmann and others, 2001) and locations of 10 x 10 km sample blocks (squares). 

When sample blocks are ranked by percentage of overall spatial change between 1973 and 2000, geographic pattern 

emerges: sample blocks that had highest amounts of change are located mostly in urban corridors southeast of 

Cleveland (see fig. 1 for location). Abbreviations for Midwest–South Central United States ecoregions are listed in 

appendix 2; also shown are parts of six Eastern United States ecoregions: Central Appalachians (CA), Eastern Great 

Lakes and Hudson Lowlands, Northern Appalachian Plateau and Uplands (NAPU), North Central Appalachians, Ridge 

and Valley (RV), and Western Allegheny Plateau. See appendix 3 for definitions of land-use/land-cover classifications. 

Note that not all land-use/land-cover classes shown in explanation may be depicted on map (colors that indicate landuse/land-cover classes in surrounding ecoregions are subdued); note also that, for this “Status and Trends of Land 

Change” study, transitional land-cover class was subdivided into mechanically disturbed and nonmechanically disturbed 

classes.

83° 82° 81° 80° 79°

42°

41°

40°

Western

Allegheny Plateau

Eastern

Corn Belt

Plains

CA

CA RV

RV

North Central

Appalachians

Huron/Erie

Lake Plains

Eastern Great Lakes

and Hudson Lowlands

SMNIDP

HELP

CANADA

NAPU

LAKE

ERIE

Ecoregion boundary

Water

Developed

Transitional

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Ice/Snow

Land-use/land-cover class

EXPLANATION

Overall spatial change

(per 10 x 10 km sample block)

15.1 – 19.8 

8.1 – 15.0

3.1 – 8.0

0.4 – 3.0

0 50 MILES

0 50 KILOMETERS
74 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Table 2. Raw estimates of change in Erie Drift Plains Ecoregion land cover, computed for each of four 

time periods between 1973 and 2000, and associated error at 85-percent confidence level.

[Estimates of change per period normalized to annual rate of change for each period]

Period Total change

(% of ecoregion)

Margin of 

error

(+/− %)

Lower 

bound

(%)

Upper bound

(%)

Standard 

error

(%)

Relative 

error

(%)

Average rate

(% per year)

Estimate of change, in percent stratum

1973–1980 1.6 0.4 1.1 2.0 0.3 18.0 0.2

1980–1986 1.9 0.5 1.4 2.3 0.3 16.8 0.3

1986–1992 2.2 0.6 1.6 2.8 0.4 19.0 0.4

1992–2000 1.9 0.5 1.4 2.3 0.3 17.3 0.2

Estimate of change, in square kilometers

1973–1980 477 127 350 604 86 18.0 68

1980–1986 572 142 430 714 96 16.8 95

1986–1992 677 190 486 867 129 19.0 113

1992–2000 570 146 424 716 98 17.3 71

Table 1. Percentage of Erie Drift Plains Ecoregion land cover 

that changed at least one time during study period (1973–2000) and 

associated statistical error.

[Most sample pixels remained unchanged (93.9 percent), whereas 6.1 percent 

changed at least once throughout study period]

Number

of

changes

Percent

of

ecoregion

Margin

of error

(+/− %)

Lower

bound

(%)

Upper

bound

(%)

Standard

error

(%)

Relative

error

(%)

1 4.9 1.2 3.7 6.1 0.8 16.3

2 1.1 0.3 0.8 1.4 0.2 20.0

3 0.1 0.1 0.1 0.2 0.0 33.0

4 0.0 0.0 0.0 0.0 0.0 57.1

Overall 

spatial 

change

6.1 1.4 4.7 7.5 0.9 15.5
Chapter 6—Erie Drift Plains Ecoregion 75

Table 3. Estimated area (and margin of error) of each land-cover class in Erie Drift Plains Ecoregion, calculated five times 

between 1973 and 2000. See appendix 3 for definitions of land-cover classifications.

Water Developed

Mechanically 

disturbed

Mining Barren Forest Grassland/

Shrubland Agriculture Wetland

Nonmechanically 

disturbed

% +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/−

Area, in percent stratum

1973 1.9 1.3 9.5 3.8 0.1 0.1 0.6 0.3 0.0 0.0 37.5 3.5 0.6 0.3 47.6 4.9 2.3 0.6 0.0 0.0

1980 2.0 1.3 10.0 3.8 0.1 0.0 0.4 0.2 0.0 0.0 37.5 3.5 0.7 0.4 47.1 4.9 2.3 0.6 0.0 0.0

1986 2.0 1.3 10.8 4.0 0.1 0.0 0.3 0.2 0.0 0.0 37.4 3.6 0.7 0.5 46.4 4.9 2.3 0.6 0.0 0.0

1992 2.0 1.3 11.7 4.1 0.1 0.1 0.3 0.2 0.0 0.0 37.1 3.6 0.8 0.5 45.7 4.9 2.3 0.6 0.0 0.0

2000 2.0 1.3 12.7 4.3 0.1 0.0 0.3 0.1 0.0 0.0 36.8 3.7 0.8 0.5 45.0 4.9 2.3 0.6 0.0 0.0

Net

change 0.1 0.1 3.2 1.2 0.0 0.0 –0.3 0.2 0.0 0.0 –0.7 0.7 0.2 0.3 –2.5 0.8 0.0 0.0 0.0 0.0

Gross

change 0.1 0.1 3.2 1.2 0.3 0.1 0.4 0.2 0.0 0.0 2.0 0.5 0.9 0.3 2.8 0.8 0.1 0.0 0.0 0.0

Area, in square kilometers

1973 576 398 2,908 1,154 31 21 178 93 0.7 1.0 11,491 1,080 169 103 14,562 1,505 707 182 0 0

1980 598 397 3,051 1,178 18 11 136 73 0.0 0.1 11,480 1,084 222 129 14,415 1,492 703 182 0 0

1986 600 399 3,295 1,218 22 11 99 51 0.0 0.0 11,449 1,089 229 138 14,220 1,500 703 182 5 7

1992 607 398 3,586 1,261 34 20 96 49 0.8 1.1 11,357 1,112 248 139 13,992 1,496 701 181 0 0

2000 608 398 3,894 1,322 30 11 80 44 0.0 0.0 11,282 1,119 232 148 13,794 1,491 702 181 0 0

Net

change 32 16 986 359 –1 14 –98 69 –0.7 1.0 –209 209 63 79 –768 258 –5 8 0 0

Gross

change 40 16 986 359 96 42 135 72 2.3 3.2 603 164 279 78 870 237 21 9 10 13
76 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Table 4. Principal land-cover conversions in Erie Drift Plains Ecoregion, showing amount of area changed (and margin of error, 

calculated at 85-percent confidence level) for each conversion during each of four time periods and also during overall study period. 

See appendix 3 for definitions of land-cover classifications.

[Values given for “other” classes are combined totals of values for other land-cover classes not listed in that time period. Abbreviations: n/a, not applicable]

Period From class To class

Area 

changed

Margin of 

error

Standard 

error Percent of 

ecoregion

Percent of all 

changes (km2) (+/− km2) (km2)

1973–1980 Forest Developed 67 36 24 0.2 13.9

Agriculture Developed 63 32 21 0.2 13.2

Mining Grassland/Shrubland 56 38 25 0.2 11.8

Grassland/Shrubland Forest 42 22 15 0.1 8.9

Agriculture Grassland/Shrubland 35 19 13 0.1 7.4

Other Other 213 n/a n/a 0.7 44.7

Totals 477 1.6 100

1980–1986 Agriculture Developed 139 68 45.6 0.5 24.3

Forest Developed 98 45 30.6 0.3 17.1

Grassland/Shrubland Forest 73 33 22.0 0.2 12.7

Agriculture Grassland/Shrubland 44 27 18.2 0.1 7.6

Mining Grassland/Shrubland 43 32 21.3 0.1 7.6

Other Other 175 n/a n/a 0.6 30.7

Totals 572 1.9 100

1986–1992 Agriculture Developed 149 76 51.6 0.5 22.1

Forest Developed 137 77 52.0 0.4 20.3

Agriculture Grassland/Shrubland 69 30 20.1 0.2 10.1

Agriculture Forest 49 27 18.0 0.2 7.2

Grassland/Shrubland Forest 44 29 19.8 0.1 6.5

Other Other 228 n/a n/a 0.7 33.7

Totals 677 2.2 100

1992–2000 Agriculture Developed 165 61 41.1 0.5 28.9

Forest Developed 108 47 32.0 0.4 18.9

Grassland/Shrubland Forest 56 25 17.2 0.2 9.8

Mining Grassland/Shrubland 29 23 15.2 0.1 5.0

Agriculture Forest 28 9 5.9 0.1 5.0

Other Other 185 n/a n/a 0.6 32.5

Totals 570 1.9 100

1973–2000

(overall)

Agriculture Developed 516 207 140.1 1.7 22.5

Forest Developed 409 173 117.3 1.3 17.8

Grassland/Shrubland Forest 215 96 65.0 0.7 9.4

Agriculture Grassland/Shrubland 166 62 42.2 0.5 7.2

Mining Grassland/Shrubland 146 103 69.3 0.5 6.4

Other Other 843 n/a n/a 2.8 36.7

Totals 2,296 7.5 100
Chapter 6—Erie Drift Plains Ecoregion 77

References Cited

Omernik, J.M., 1987, Ecoregions of the conterminous United 

States: Annals of the Association of American Geographers, 

v. 77, no. 1, p. 118–125. 

U.S. Department of Agriculture, 2012, Census of agriculture 

historical archive: U.S. Department of Agriculture database, 

accessed on November 21, 2012, at http://agcensus.mannlib.

cornell.edu/AgCensus/homepage.do;jsessionid=4328FAD2

394C3CD6DB18A237F39D129D. 

U.S. Environmental Protection Agency, 2013, Great Lakes 

Areas of Concern—Cuyahoga River: U.S. Environmental 

Protection Agency database, accessed April 24, 2014, at 

http://www.epa.gov/greatlakes/aoc/cuyahoga/.

Vogelmann, J.E., Howard, S.M., Yang, L., Larson, C.R., 

Wylie, B.K., and van Driel, N., 2001, Completion of the 

1990s National Land Cover Data Set for the conterminous 

United States from Landsat Thematic Mapper data and 

ancillary data sources: Photogrammetric Engineering & 

Remote Sensing, v. 67, p. 650–662.

Wiken, E., Jiménez Nava, F., and Griffith, G., 2011, North 

American terrestrial ecoregions—Level III: Montreal, 

Canada, Commission for Environmental Cooperation, 

accessed November 5, 2012, 149 p., at http://www.cec.

org/Storage/133/15860_QA07.30-32_NP_NA_Terrestrial_

Ecoregions_Level_3_Final-2june11.pdf.

Woods, A.J., Omernik, J.M., and Brown, D.D., 1999, Level III 

and IV ecoregions of Delaware, Maryland, Pennsylvania, 

Virginia, and West Virginia: U.S. Environmental Protection 

Agency, National Health and Environmental Effects Research 

Laboratory, Corvallis, Oregon, 57 p., accessed November 26, 

2012, at ftp://ftp.epa.gov/wed/ecoregions/reg3/reg3_eco_desc.

doc.

Midwest Agricultural Ecoregions

Chapter 7

Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000 

Edited by Roger F. Auch and Krista A. Karstensen 

U.S. Geological Survey Professional Paper 1794–C, 2015

Southeastern Wisconsin Till Plains Ecoregion 

By Mark S. Brooks

Figure 1. Map of Southeastern Wisconsin Till Plains Ecoregion and surrounding ecoregions, showing land-use/land-cover classes 

from 1992 National Land Cover Dataset (Vogelmann and others, 2001); note that not all land-use/land-cover classes shown in explanation 

may be depicted on map; note also that, for this “Status and Trends of Land Change” study, transitional land-cover class was subdivided 

into mechanically disturbed and nonmechanically disturbed classes. Squares indicate locations of 10 x 10 km sample blocks analyzed 

in study. Index map shows locations of geographic features mentioned in text. Abbreviations for Midwest–South Central United States 

ecoregions are listed in appendix 2. See appendix 3 for definitions of land-use/land-cover classifications.

Ecoregion Description 

The Southeastern Wisconsin Till Plains Ecoregion covers 

about 30,999 km2 (11,969 mi2) (fig. 1) (Omernik, 1987; 

Wiken and others, 2011). With the exception of a small part 

that extends into northern Illinois, most of the ecoregion is in 

southeastern Wisconsin. It is bordered by the North Central 

Hardwood Forests Ecoregion to the north, the Driftless Area 

Ecoregion to the west, the Central Corn Belt Plains Ecoregion 

to the south, and Lake Michigan to the east. 

The topography of the ecoregion primarily was formed 

by glacial processes during Wisconsin-age glaciation. Glacial 

89° 88°

90°

44°N

43°

44°

Driftless

Area

North Central

Hardwood Forests

NCHF

Central Corn

Belt Plains

Lake

Michigan

WI

MI

IL

Southeastern

Wisconsin

Till Plains

Ecoregion

0 50 MILES

0 50 KILOMETERS

Ecoregion boundary

Sample block (10 x 10 km)

Land-use/land-cover class

Water

Developed

Transitional

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Ice/Snow

EXPLANATION

Milwaukee

MILWAUKEE COUNTY

WISCONSIN

ILLINOIS

Evansville

Janesville Elkhorn

Appleton

Madison

Green Bay

LAKE MICHIGAN

Lake

Wisconsin Wisconsin R. Lake

Winnebago

KETTLE MORAINE

STATE FOREST

landforms, including irregular till plains, end moraines, kettles, 

and drumlins, are responsible for the rolling hills (figs. 2,3,4) 

and lowland plains in the ecoregion. Many wetlands and lakes 

of various sizes dot the landscape. The soils are a lime-rich till, 

overlain in most areas by a silt-loam loess cap that varies in 

thickness from about a meter on hilltops to more than 122m 

in the lowland plains (Wisconsin Department of Natural 

Resources, 2011). 

The ecoregion has a humid continental climate, with an 

average January temperature of –11°C and an average July 
82 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

temperature of 21°C. The average annual precipitation is about 

840 mm (33 in.), with an average annual snowfall of 1,320 

mm (52 in.) per year (Wisconsin State Climatology Office, 

2011). The waters of Lake Michigan have a moderating 

effect on temperatures near the shoreline, and so summers are 

somewhat cooler and winters are warmer along the lake when 

compared to areas further inland.

Prior to European-American settlement, the ecoregion’s 

upland vegetation was a mix of prairie, oak forests (Quercus 

spp.), savanna, and maple-dominated forests (Acer spp.). Wetmesic prairies, southern sedge meadows, emergent marshes, 

and calcareous fens were present in lowland areas. Today 

(2014), agricultural land-use practices and developed land 

have redefined the landscape because they have replaced much 

of the original vegetation. Forests remain on steeper terrain 

not suitable for agriculture (Wisconsin Department of Natural 

Resources, 2011), and wetlands constituted about 7 percent of 

the ecoregion during the study period. 

Dairy farming is the leading agricultural activity, and 

major food products include milk and cheese. Corn, hay, 

and other forage crops support dairy operations. Other 

crops include soybeans (figs. 5, 6), potatoes, wheat, barley, 

tobacco, beets, beans, peas, cucumbers, apples, cherries, and 

cranberries (U.S. Department of Agriculture, 2008). The 

diverse industrial base includes the manufacturing of tractors 

and other farm machinery, as well as engines, turbines, and 

construction equipment.

Figure 2. South-facing view of rolling, forested upland areas, 

with Lake Wisconsin, Wisconsin, in distance.

Figure 3. Kettle depression in Kettle Moraine State Forest, 

Wisconsin. 

Figure 4. Looking north along waterway just south of Elkhorn, 

Wisconsin. 

Figure 5. Irrigated soybean field and large grain-storage 

complex, east of Evansville, Wisconsin.

Figure 6. Expansive fields of soybeans and corn, east of 

Janesville, Wisconsin.
Chapter 7—Southeastern Wisconsin Till Plains Ecoregion 83

Figure 7. Overall spatial change in Southeastern Wisconsin Till 

Plains Ecoregion (SEWTP; darker bars) compared with that of all 17 

Midwest–South Central United States ecoregions (lighter bars). Each 

horizontal set of bars shows proportions of ecoregion that changed 

during one, two, three, or four time periods; highest level of spatial 

change in Southeastern Wisconsin Till Plains Ecoregion (four time 

periods) labeled for clarity. See table 2 for years covered by each time 

period. See appendix 2 for key to ecoregion abbreviations.

Figure 8. Estimates of land-cover change per time period, 

normalized to annual rates of change for all 17 Midwest–South 

Central United States ecoregions (gray bars). Estimates of change 

for Southeastern Wisconsin Till Plains Ecoregion are represented 

by red bars in each time period.

0 12 24 36

Area, as percent of ecoregion

Ecoregion 

DA

HELP

CCBP

SMNIDP

NCHF

BM

IRL

SEWTP

OH

EDP

ECBP

NMW

AV

MAP

NLF

SCP

OM

EXPLANATION

Change in one time period

Change in two time periods

Change in three time periods

Change in four time periods

Change in four time periods

0.5

0.0

1.0

1.5

2.5

3.0

2.0

3.5

1973 to 1980 1980 to 1986 1986 to 1992 1992 to 2000

Average annual change, as percent of ecoregion

Time period

The population of the ecoregion increased notably 

during the study period. Major cities within the ecoregion 

include (2000 populations) Milwaukee (596,974), Madison 

(208,054), Green Bay (102,313), and Appleton (70,087), 

Wisconsin. However, although the city of Milwaukee and 

Milwaukee County continued to have the highest population 

totals within the ecoregion, the populations of both decreased 

during the study period (U.S. Census Bureau, 2011; Wisconsin 

Department of Administration, 2011). 

Contemporary Land-Cover Change 

(1973 to 2000)

The overall spatial change (the percentage of land area 

that changed at least one time) in the Southeastern Wisconsin 

Till Plains Ecoregion between 1973 and 2000 is estimated 

at 5.7 percent (table 1). Compared to other Midwest–South 

Central United States ecoregions, change in the Southeastern 

Wisconsin Till Plains Ecoregion was moderate (fig. 7), 

with an estimated 0.4 percent changing in two or more time 

periods; however, most of the land (about 94.3 percent) did 

not change during the study period (table 1). Estimated change 

per time period varied slightly between 1973 and 2000. The 

first three time periods (1973–1980, 1980–1986, 1986–1992) 

showed similar amounts of change, whereas the last time 

period (1992–2000) had the greatest amount of change (table 

2). When normalized to an average annual rate of change to 

account for uneven time periods, the first three time periods 

showed a minimal change of about 0.2 percent (66.0 to 68.6 

km2) per year (table 2; fig. 8), which increased to 0.3 percent 

(79.5 km2) per year in the last time period (1992–2000). 

The estimated area of most land-cover classes changed 

less than 1 percent during the study period, the exceptions 

being agriculture and developed, the only land-cover classes 

that experienced observable net change. These land-cover 

classes had the most significant net losses and net gains during 

the study period, with a net loss of about 4.2 percent (1,301 

km2) of agricultural land and a net gain of about 4.0 percent 

(1,242 km2) of developed land (table 3). In 2000, agriculture 

was the predominant land cover at about 61.9 percent of the 

ecoregion, followed by forest at about 11.9 percent of the 

ecoregion, with almost no net change between 1973 and 2000. 

Developed expanded to cover an estimated 10.4 percent of the 

ecoregion, whereas wetland and water accounted for about 7.1 

and 6.2 percent of the ecoregion, respectively (table 3). 

The leading land-cover conversions between 1973 and 

2000 primarily involved changes in the agriculture, forest, 

grassland/shrubland, and developed land-cover classes (table 

4; fig. 9). An estimated 996 km2 of agricultural land converted 

to developed land. Forested land and grassland/shrubland also 

converted to developed land, with a loss of about 110 km2

and 97 km2, respectively. Other leading conversions were 206 

km2 of agriculture to grassland/shrubland (possibly the result 

of farmland abandonment), as well as an estimated 97 km2
84 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

−2

−1

0

1

2

1973–1980 1980–1986 

Time period

1986–1992 1992–2000 

Area changed, as percent of ecoregion 

Water

Developed

Mechanically disturbed

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Nonmechanically disturbed

Ice/Snow

EXPLANATION

LAND-USE/LAND-COVER CLASS

Figure 9. Normalized average net change in Southeastern 

Wisconsin Till Plains Ecoregion by time period for each land-cover 

class. Bars above zero axis represent net gain, whereas bars 

below zero represent net loss. Note that not all land-cover classes 

shown in explanation may be represented in figure. See appendix 

3 for definitions of land-use and land-cover classifications.

Figure 10. Exurban residential development, north of Appleton, 

Wisconsin.

of grassland/shrubland to forest (table 4). However, because 

of the different types of changes affecting these land-cover 

classes, grassland/shrubland and forest had almost no overall 

net change between 1973 and 2000 (table 3).

The Southeastern Wisconsin Till Plains Ecoregion 

experienced moderate population growth during the 

study period, and the resulting expansion of residential 

and commercial development (fig. 10) led to decreases in 

farmland. Grassland/shrubland and forest also have decreased 

overall because of losses to developed without replacements 

coming from agriculture (conversions from agriculture to 

grassland/shrubland) and grassland/shrubland (conversions 

from grassland/shrubland to forest). Agriculture remained the 

dominant land-cover class between 1973 and 2000, despite its 

decrease of about 6.3 percent. 
Chapter 7—Southeastern Wisconsin Till Plains Ecoregion 85

Table 2. Raw estimates of change in Southeastern Wisconsin Till Plains Ecoregion land cover, 

computed for each of four time periods between 1973 and 2000, and associated error at 85-percent 

confidence level.

[Estimates of change per period normalized to annual rate of change for each time period]

Period Total change

(% of ecoregion)

Margin of 

error

(+/− %)

Lower 

bound

(%)

Upper bound

(%)

Standard 

error

(%)

Relative 

error

(%)

Average rate

(% per year)

Estimate of change, in percent stratum

1973–1980 1.5 0.5 1.1 2.0 0.3 20.3 0.2

1980–1986 1.3 0.3 1.0 1.6 0.2 17.0 0.2

1986–1992 1.3 0.4 0.9 1.6 0.3 20.0 0.2

1992–2000 2.1 0.5 1.6 2.5 0.3 16.3 0.3

Estimate of change, in square kilometers

1973–1980 480 143 337 623 98 20.3 69

1980–1986 397 99 298 497 68 17.0 66

1986–1992 395 116 279 511 79 20.0 66

1992–2000 636 152 484 788 103 16.3 80

Table 1. Percentage of Southeastern Wisconsin Till Plains 

Ecoregion land cover that changed at least one time during study 

period (1973–2000) and associated statistical error.

[Most sample pixels remained unchanged (94.3 percent), whereas 5.7 percent 

changed at least once throughout study period] 

Number

of

changes

Percent

of

ecoregion

Margin

of error

(+/− %)

Lower

bound

(%)

Upper

bound

(%)

Standard

error

(%)

Relative

error

(%)

1 5.2 1.2 4.0 6.5 0.8 15.9

2 0.4 0.1 0.3 0.6 0.1 23.1

3 0.0 0.0 0.0 0.0 0.0 32.1

4 0.0 0.0 0.0 0.0 0.0 73.2

Overall 

spatial 

change

5.7 1.3 4.4 7.0 0.9 15.4
86 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Table 3. Estimated area (and margin of error) of each land-cover class in Southeastern Wisconsin Till Plains Ecoregion, calculated 

five times between 1973 and 2000. See appendix 3 for definitions of land-cover classifications.

Water Developed

Mechanically 

disturbed

Mining Barren Forest Grassland/

Shrubland Agriculture Wetland

Nonmechanically 

disturbed

% +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/−

Area, in percent stratum

1973 6.2 3.0 6.4 2.4 0.1 0.1 0.2 0.1 0.0 0.0 11.8 2.1 2.2 0.8 66.1 4.5 7.1 1.7 0.0 0.0

1980 6.2 3.0 7.4 2.7 0.0 0.0 0.2 0.1 0.0 0.0 11.8 2.1 2.2 0.8 65.0 4.6 7.0 1.7 0.0 0.0

1986 6.2 3.0 8.2 2.9 0.0 0.0 0.2 0.1 0.0 0.0 11.9 2.1 2.2 0.8 64.2 4.7 7.1 1.7 0.0 0.0

1992 6.2 3.0 9.0 3.1 0.0 0.0 0.2 0.1 0.0 0.0 11.9 2.1 2.2 0.8 63.4 4.8 7.0 1.7 0.0 0.0

2000 6.2 3.0 10.4 3.3 0.1 0.0 0.3 0.1 0.0 0.0 11.9 2.1 2.2 0.8 61.9 4.9 7.1 1.7 0.0 0.0

Net

change 0.0 0.0 4.0 1.1 0.0 0.1 0.1 0.1 0.0 0.0 0.0 0.3 0.0 0.2 –4.2 1.1 0.0 0.1 0.0 0.0

Gross

change 0.3 0.1 4.0 1.1 0.2 0.1 0.2 0.1 0.0 0.0 0.7 0.3 0.7 0.2 4.3 1.1 0.3 0.1 0.0 0.0

Area, in square kilometers

1973 1,915 917 1,973 738 25 26 50 18 10.0 7.9 3,671 649 679 240 20,489 1,399 2,186 537 0 0

1980 1,933 916 2,309 846 2 2 56 21 10.0 7.9 3,673 652 684 238 20,159 1,433 2,175 537 0 0

1986 1,916 917 2,540 890 3 2 60 24 10.0 7.9 3,696 654 681 238 19,905 1,459 2,187 537 0 0

1992 1,922 916 2,779 949 11 7 71 30 10.0 7.9 3,680 649 683 242 19,664 1,487 2,178 535 0 0

2000 1,923 916 3,215 1,016 20 14 87 35 10.1 7.9 3,681 648 686 254 19,187 1,533 2,188 532 0 0

Net

change 8 14 1,242 339 –5 29 36 18 0.1 0.1 10 94 7 50 –1,301 335 2 20 0 0

Gross

change 84 29 1,242 339 64 31 48 18 0.1 0.1 232 84 217 76 1,328 330 94 33 0 0
Chapter 7—Southeastern Wisconsin Till Plains Ecoregion 87

Table 4. Principal land-cover conversions in Southeastern Wisconsin Till Plains Ecoregion, showing amount of area changed (and 

margin of error, calculated at 85-percent confidence level) for each conversion during each of four time periods and also during 

overall study period. See appendix 3 for definitions of land-cover classifications.

[Values given for “other” class are combined totals of values for other land-cover classes not listed in that time period. Abbreviations: n/a, not applicable]

Period From class To class

Area 

changed

Margin of 

error

Standard 

error Percent of 

ecoregion

Percent of all 

changes (km2) (+/− km2) (km2)

1973–1980 Agriculture Developed 265 108 74 0.9 55.2

Agriculture Grassland/Shrubland 50 26 18 0.2 10.4

Forest Developed 29 18 12 0.1 6.0

Grassland/Shrubland Developed 23 13 9 0.1 4.8

Grassland/Shrubland Forest 23 12 8 0.1 4.8

Other Other 90 n/a n/a 0.3 18.8

Totals 480 1.5 100

1980–1986 Agriculture Developed 185 73 49.6 0.6 46.4

Agriculture Grassland/Shrubland 51 24 16.3 0.2 12.9

Grassland/Shrubland Forest 27 14 9.4 0.1 6.9

Grassland/Shrubland Developed 26 14 9.8 0.1 6.6

Agriculture Forest 22 21 14.1 0.1 5.5

Other Other 86 n/a n/a 0.3 21.7

Totals 397 1.3 100

1986–1992 Agriculture Developed 175 63 42.9 0.6 44.2

Agriculture Grassland/Shrubland 52 22 14.7 0.2 13.2

Forest Developed 37 27 18.1 0.1 9.4

Grassland/Shrubland Forest 25 23 15.5 0.1 6.3

Grassland/Shrubland Developed 25 11 7.6 0.1 6.3

Other Other 82 n/a n/a 0.3 20.7

Totals 395 1.3 100

1992–2000 Agriculture Developed 372 103 69.8 1.2 58.5

Agriculture Grassland/Shrubland 53 35 23.7 0.2 8.3

Forest Developed 28 18 12.1 0.1 4.4

Grassland/Shrubland Developed 23 10 6.9 0.1 3.7

Grassland/Shrubland Forest 21 12 7.9 0.1 3.4

Other Other 139 n/a n/a 0.4 21.8

Totals 636 2.1 100

1973–2000

(overall)

Agriculture Developed 996 285 194.3 3.2 52.2

Agriculture Grassland/Shrubland 206 81 55.4 0.7 10.8

Forest Developed 110 58 39.4 0.4 5.8

Grassland/Shrubland Developed 97 40 27.4 0.3 5.1

Grassland/Shrubland Forest 97 47 32.2 0.3 5.1

Other Other 403 n/a n/a 1.3 21.1

Totals 1,909 6.2 100
88 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

References Cited

Omernik, J.M., 1987, Ecoregions of the conterminous 

United States: Annals of the Association of American 

Geographers, v. 77, no. 1, p. 118–125.

U.S. Census Bureau, 2011, Census of population and 

housing, 1970-2000: U.S. Census Bureau database, 

accessed March 18, 2014, at http://www.census.gov/prod/

www/decennial.html.

U.S. Department of Agriculture, 2008, The census of 

agriculture—1992 census publications: U.S. Department 

of Agriculture, National Agricultural Statistics Service, 

accessed February 1, 2011, at http://www.agcensus.usda.

gov/Publications/1992/Volume_1/Wisconsin/index.asp.

Vogelmann, J.E., Howard, S.M., Yang, L., Larson, C.R., 

Wylie, B.K., and van Driel, N., 2001, Completion of the 

1990s National Land Cover Data Set for the conterminous 

United States from Landsat Thematic Mapper data and 

ancillary data sources: Photogrammetric Engineering & 

Remote Sensing, v. 67, p. 650–662.

Wiken, E., Jiménez Nava, F., and Griffith, G., 2011, North 

American terrestrial ecoregions—Level III: Montreal, 

Canada, Commission for Environmental Cooperation, 149 

p., accessed February 1, 2013, at http://www.cec.org/Storage/133/15860_QA07.30-32_NP_NA_Terrestrial_Ecoregions_Level_3_Final-2june11.pdf.

Wisconsin Department of Administration, 2011, Wisconsin 

population and housing estimates: Madison, Wisconsin 

Department of Administration Web site, accessed February 1, 2011, at http://www.doa.state.wi.us/subcategory.

asp?linksubcatid=96&locid=9.

Wisconsin Department of Natural Resources, 2011, Southeast 

glacial plains ecological landscape: Wisconsin Department of Natural Resources Web site, accessed January 

10, 2011, at http://dnr.wi.gov/topic/landscapes/index.

asp?mode=detail&Landscape=9. 

Wisconsin State Climatology Office, 2011, Statewide Wisconsin climate: Madison, University of Wisconsin Atmospheric 

and Oceanic Sciences Department, Wisconsin State Climatology Office Web site, accessed on January 10, 2011, at 

http://www.aos.wisc.edu/~sco/clim-history/state/index.html.
Chapter 8

Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000 

Edited by Roger F. Auch and Krista A. Karstensen 

U.S. Geological Survey Professional Paper 1794–C, 2015

Huron/Erie Lake Plains Ecoregion 

By Steven Kambly

Ecoregion Description 

The Huron/Erie Lake Plains 

Ecoregion consists of two separate, 

noncontiguous parts, which cover 

27,362 km2 (10,565 mi2) in Michigan, 

Ohio, and Indiana (fig. 1) (Omernik, 

1987; Wiken and others, 2011). The 

northern part, which lies along the coast of 

Michigan’s “Thumb” region and includes 

several counties south and west of Saginaw 

Bay, in Lake Huron, is bounded by the 

Northern Lakes and Forests Ecoregion and 

the Southern Michigan/Northern Indiana 

Drift Plains Ecoregion. The southern part, 

which extends from the western shoreline 

of Lake Erie (from Sandusky, Ohio, to 

metropolitan Detroit, Michigan) southwest 

towards Fort Wayne, Indiana, is bounded 

by the Southern Michigan/Northern 

Indiana Drift Plains, Eastern Corn Belt 

Plains, and Eastern Great Lakes and 

Hudson Lowlands Ecoregions. The climate 

of the ecoregion is humid continental; the 

average annual precipitation ranges from 

about 700 to 915 mm (29–36 in.), and the 

annual frost-free period ranges from 150 to 

200 days (Wiken and others, 2011). 

The Huron/Erie Lake Plains 

Ecoregion, which is underlain by 

glacial lakebed deposits, is “a broad, 

fertile, nearly flat plain punctuated by 

relic sand dunes, beach ridges, and end 

moraines” (U.S. Environmental Protection 

Agency, 2002, p. 11). American elm–ash 

(Ulmus americana and Fraxinus spp., 

respectively) swamps and American beech 

(Fagus grandifolia) forests, along with 

the mixed oak (Quercus spp.) forests 

and oak savannas that are found on drier, 

sandier soils, were widespread before 

the large-scale clearing of forests and 

draining of wetlands for agriculture in the 

19th century (fig. 2) (U.S. Environmental 

Protection Agency, 2002). 

84° 83° 82°

85°

44°

43°

42°

41°

Eastern Corn Belt Plains

Southern Michigan/

Northern Indiana

Drift Plains

Northern Lakes

and Forests

EDP

EGLHL

LAKE

ERIE

LAKE HURON

CANADA

IN

MI

OH

Huron/Erie

Lake Plains

Ecoregion

0 50 MILES

0 50 KILOMETERS

Ecoregion boundary

Sample block (10 x 10 km)

Land-use/land-cover class

Water

Developed

Transitional

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Ice/Snow

EXPLANATION

INDIANA

MICHIGAN

OHIO

CANADA

“THUMB”

REGION

Saginaw Bay LAKE

HURON

LAKE

ERIE

Detroit

Sandusky

Saginaw

Toledo

Milan

Fort

Wayne

Figure 1. Map of Huron/Erie Lake Plains Ecoregion and surrounding ecoregions, 

showing land-use/land-cover classes from 1992 National Land Cover Dataset 

(Vogelmann and others, 2001); note that not all land-use/land-cover classes 

shown in explanation may be depicted on map; note also that, for this “Status and 

Trends of Land Change” study, transitional land-cover class was subdivided into 

mechanically disturbed and nonmechanically disturbed classes. Squares indicate 

locations of 10 x 10 km sample blocks analyzed in study. Index map shows locations 

of geographic features mentioned in text. Abbreviations for Midwest–South Central 

United States ecoregions are listed in appendix 2. Also shown is part of one Eastern 

United States ecoregion, Eastern Great Lakes and Hudson Lowlands (EGLHL). See 

appendix 3 for definitions of land-use/land-cover classifications.
90 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

The ecoregion is farmed intensively, with corn, soybeans, 

and wheat as its major crops, but it also is known for various 

vegetable crops, sugar beets, and dry beans (fig. 3). Sugar-beet 

production in the lowlands around Saginaw, Michigan, and 

in the northern part of Michigan’s “Thumb” region increased 

during the 27-year study period, and the area is a major 

source of the nation’s sugar-beet supply. Michigan’s dry-bean 

production is second only to that of North Dakota.

The Huron/Erie Lake Plains Ecoregion includes the 

metropolitan areas of Detroit, Michigan, and Toledo, Ohio, 

both of which experienced industrial decline (fig. 4) and slow 

population growth and (or) population loss during the study 

period (Frey, 2012). Large-scale population shifts from city 

centers to outlying areas (fig. 5) led to increased suburban 

and exurban development, primarily through the conversion 

of farmland and forests. Moreover, low-density development 

patterns, combined with smaller household sizes, have resulted 

in a far more rapid expansion of urbanized land than would be 

expected from slow-growing (or decreasing) population levels 

(Michigan Land Use Leadership Council, 2003). 

Contemporary Land-Cover Change 

(1973 to 2000)

The overall spatial change (the percentage of land area 

that changed at least one time) in the Huron/Lake Erie Plains 

Ecoregion between 1973 and 2000 is estimated at 2.7 percent 

(table 1). About 2.3 percent of the ecoregion changed only 

once during the study period, whereas about 0.4 percent 

changed twice. An estimated 97.3 percent of the land area did 

not change. Compared to other Midwest–South Central United 

States ecoregions, change in the Huron/Erie Lake Plains 

Ecoregion was low, indicating that the ecoregion remained 

relatively stable during the study period (fig. 6): the estimated 

percent change per time period increased overall from 0.6 

percent between 1973 and 1980 to 1.1 percent between 1992 

Figure 3. Crops grown in lake plains of Michigan’s “Thumb” 

region, in Huron/Erie Lake Plains Ecoregion. A, Dry beans. B, 

Sugar beets.

Figure 4. Industrial abandonment in southwestern 

Detroit, Michigan.

Figure 2. Oak savanna and mixed-oak forest, which are found 

on dry, sandy soils in Huron/Erie Lake Plains Ecoregion.

A

B
Chapter 8—Huron/Erie Lake Plains Ecoregion 91

Figure 7. Estimates of land-cover change per time period, 

normalized to annual rates of change for all 17 Midwest–South 

Central United States ecoregions (gray bars). Estimates of change 

for Huron/Erie Lake Plains Ecoregion are represented by red bars 

in each time period.

Figure 5. New exurban housing near Milan, Michigan.

Figure 6. Overall spatial change in Huron/Erie Lake Plains 

Ecoregion (HELP; darker bars) compared with that of all 17 

Midwest–South Central United States ecoregions (lighter bars). 

Each horizontal set of bars shows proportions of ecoregion that 

changed during one, two, three, or four time periods; highest level 

of spatial change in Huron/Erie Lake Plains Ecoregion (four time 

periods) labeled for clarity. See table 2 for years covered by each 

time period. See appendix 2 for key to ecoregion abbreviations.

0 12 24 36

Area, as percent of ecoregion

Ecoregion 

DA

HELP

CCBP

SMNIDP

NCHF

BM

IRL

SEWTP

OH

EDP

ECBP

NMW

AV

MAP

NLF

SCP

OM

EXPLANATION

Change in one time period

Change in two time periods

Change in three time periods

Change in four time periods

Change in four time periods

0.5

0.0

1.0

1.5

2.5

3.0

2.0

3.5

1973 to 1980 1980 to 1986 1986 to 1992 1992 to 2000

Average annual change, as percent of ecoregion

Time period

and 2000 (table 2; fig. 7). The normalized average annual 

change rate ranged from 23 to 38 km2 per year (table 2). 

Only two land-cover classes, developed and agriculture, 

had greater than 1 percent change during the study period 

(table 3). Most change in the ecoregion occurred as a result of 

conversion from agriculture to developed. Overall, agriculture 

decreased by an estimated 350 km2 (a 1.9 percent loss), nearly 

as much as the increase in developed (361 km2). Some loss of 

agricultural land, however, was caused by conversions from 

agriculture to grassland/shrubland, which may have resulted 

from farmland abandonment. Forest land decreased by 2.4 

percent from its 1973 base (0.3 percent of the ecoregion area; 

table 3), primarily because of conversions from forest to 

developed. The percentages of areal change for the remaining 

land-cover classes were minimal (fig. 8).

The 18.6 percent increase in developed land (from its 

1973 base amount) between 1973 and 2000 was the result of 

conversions from agriculture, forest, mechanically disturbed, 

and other more natural land covers. The most common 

conversion throughout all time periods was from agriculture 

to developed. Between 1973 and 2000, conversions from 

agriculture to developed increased significantly, from 57 km2

in the first time period to 100 km2 in the last time period for 

an estimated total of 277 km2 (table 4). About 68 km2 of 

forest converted to developed as well, the third most common 

conversion during the study period. 

Forest to mechanically disturbed, the fourth most 

common conversion during the study period, mainly 

resulted from timber harvesting on state forest lands in the 

northwestern part of the ecoregion. This is in contrast to areas 

in the eastern and southern parts of the ecoregion, which 

largely were farmland interspersed with relatively small areas 

of privately owned forest.

Agriculture to grassland/shrubland was the fifth most 

common conversion between 1973 and 2000. Furthermore, 

most grassland/shrubland, having converted from farmland, 

eventually converted to forest. The decrease in agriculture 

through conversions to grassland/shrubland was an estimated 

50 km2. When combined with conversions directly to forest 

(42km2, included as part of the “Other” class in the “1973–

2000 (overall)” section of table 4), agriculture decreased by 

92 km2, which is much less than the estimated 277 km2 of 

agriculture that converted to developed during the study period.
92 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Wetland to water and water to wetland were the second 

and sixth most common conversions, respectively, during the 

study period. Although wetlands were drained extensively 

prior to the 20th century to facilitate the growth of farms, new 

settlements, and transportation routes, large areas of wetlands 

are now protected within publicly owned lands; about 3.5 

percent of the ecoregion remained as wetlands during the 

study period (table 3).

Expansion of developed at the expense of agriculture and 

forest was the most significant land-cover change between 

1973 and 2000. More land converted to developed, which 

increased by about 18.6 percent during the study period, than to 

any other land-cover class. Most of the decrease in agriculture 

and forest during the study period was attributable to the 

advance of developed land into suburban and rural settings.

Figure 9. Wetlands in Huron/Erie Lake Plains Ecoregion. Once 

pervasive, many are now largely concentrated on public lands.

Figure 8. Normalized average net change in Huron/Erie Lake 

Plains Ecoregion by time period for each land-cover class. Bars 

above zero axis represent net gain, whereas bars below zero 

represent net loss. Note that not all land-cover classes shown 

in explanation may be represented in figure. See appendix 3 for 

definitions of land-use and land-cover classifications.

−1

−0.5

0

0.5

1

1973–1980 1980–1986 

Time period

1986–1992 1992–2000 

Area changed, as percent of ecoregion 

Water

Developed

Mechanically disturbed

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Nonmechanically disturbed

Ice/Snow

EXPLANATION

LAND-USE/LAND-COVER CLASS
Chapter 8—Huron/Erie Lake Plains Ecoregion 93

Table 2. Raw estimates of change in Huron/Erie Lake Plains Ecoregion land cover, computed for each 

of four time periods between 1973 and 2000, and associated error at 85-percent confidence level.

[Estimates of change per period normalized to annual rate of change for each period]

Period Total change

(% of ecoregion)

Margin of 

error

(+/− %)

Lower 

bound

(%)

Upper bound

(%)

Standard 

error

(%)

Relative 

error

(%)

Average rate

(% per year)

Estimate of change, in percent stratum

1973–1980 0.6 0.3 0.3 0.9 0.2 30.5 0.1

1980–1986 0.6 0.2 0.4 0.7 0.1 22.5 0.1

1986–1992 0.8 0.3 0.6 1.1 0.2 23.5 0.1

1992–2000 1.1 0.4 0.7 1.5 0.3 23.5 0.1

Estimate of change, in square kilometers

1973–1980 164 74 91 238 50 30.5 23

1980–1986 154 51 103 205 35 22.5 26

1986–1992 231 79 151 310 54 23.5 38

1992–2000 303 104 198 407 71 23.5 38

Table 1. Percentage of Huron/Erie Lake Plains Ecoregion land 

cover that changed at least one time during study period (1973–

2000) and associated statistical error.

[Most sample pixels remained unchanged (97.2 percent), whereas 2.8 percent 

changed at least once throughout study period]

Number

of

changes

Percent

of

ecoregion

Margin

of error

(+/− %)

Lower

bound

(%)

Upper

bound

(%)

Standard

error

(%)

Relative

error

(%)

1 2.3 0.7 1.6 3.0 0.5 21.1

2 0.4 0.2 0.2 0.5 0.1 34.6

3 0.0 0.0 0.0 0.1 0.0 53.8

4 0.0 0.0 0.0 0.0 0.0 0.0

Overall 

spatial 

change

2.7 0.8 1.8 3.5 0.6 21.2
94 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Table 3. Estimated area (and margin of error) of each land-cover class in Huron/Erie Lake Plains Ecoregion, calculated five times 

between 1973 and 2000. See appendix 3 for definitions of land-cover classifications.

Water Developed

Mechanically 

disturbed

Mining Barren Forest Grassland/

Shrubland Agriculture Wetland

Nonmechanically 

disturbed

% +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/−

Area, in percent stratum

1973 9.6 6.2 7.0 3.3 0.1 0.1 0.2 0.1 0.0 0.0 12.8 2.7 0.2 0.1 66.6 5.0 3.4 1.1 0.0 0.0

1980 9.6 6.2 7.3 3.4 0.0 0.0 0.2 0.1 0.0 0.0 12.8 2.7 0.2 0.1 66.4 5.0 3.4 1.1 0.0 0.0

1986 9.6 6.2 7.5 3.4 0.1 0.1 0.2 0.1 0.0 0.0 12.7 2.7 0.3 0.1 66.2 5.1 3.4 1.0 0.0 0.0

1992 9.7 6.2 7.8 3.4 0.0 0.0 0.2 0.1 0.0 0.0 12.7 2.7 0.3 0.1 65.8 5.1 3.4 1.0 0.0 0.0

2000 9.6 6.2 8.3 3.5 0.2 0.1 0.2 0.1 0.0 0.0 12.5 2.6 0.3 0.1 65.4 5.1 3.5 1.1 0.0 0.0

Net

change 0.0 0.1 1.3 0.6 0.1 0.1 0.0 0.0 0.0 0.0 –0.3 0.2 0.1 0.1 –1.3 0.5 0.1 0.1 0.0 0.0

Gross

change 0.3 0.2 1.4 0.6 0.3 0.2 0.1 0.0 0.0 0.0 0.6 0.3 0.3 0.1 1.4 0.5 0.3 0.2 0.0 0.0

Area, in square kilometers

1973 2,629 1,696 1,920 913 19 16 45 24 8.5 8.2 3,506 744 61 27 18,235 1,366 939 290 0 0

1980 2,623 1,695 1,997 926 9 8 47 24 9.0 8.7 3,491 743 65 30 18,177 1,378 944 292 0 0

1986 2,640 1,699 2,055 930 15 16 49 25 6.3 5.5 3,473 741 75 32 18,120 1,386 928 287 0 0

1992 2,641 1,692 2,144 935 13 10 55 26 7.8 7.2 3,477 745 92 33 18,005 1,392 928 284 0 0

2000 2,616 1,690 2,281 958 42 36 57 26 7.6 7.1 3,423 722 94 33 17,885 1,398 956 291 0 0

Net

change –13 24 361 166 23 30 12 8 –0.8 1.3 –83 67 32 17 –350 133 18 24 0 0

Gross

change 89 46 374 164 74 47 23 12 4.9 6.2 171 69 76 24 380 130 92 48 0 0
Chapter 8—Huron/Erie Lake Plains Ecoregion 95

Table 4. Principal land-cover conversions in Huron/Erie Lake Plains Ecoregion, showing amount of area changed (and margin of 

error, calculated at 85-percent confidence level) for each conversion during each of four time periods and also during overall study 

period. See appendix 3 for definitions of land-cover classifications.

[Values given for “other” classes are combined totals of values for other land-cover classes not listed in that time period. Abbreviations: n/a, not applicable]

Period From class To class

Area 

changed

Margin of 

error

Standard 

error Percent of 

ecoregion

Percent

of all 

changes (km2) (+/− km2) (km2)

1973–1980 Agriculture Developed 57 40 27 0.2 34.6

Forest Agriculture 14 5 4 0.1 8.6

Forest Developed 14 13 9 0.1 8.4

Water Wetland 11 12 8 0.0 6.9

Mechanically disturbed Forest 8 9 6 0.0 5.1

Other Other 60 n/a n/a 0.2 36.4

Totals 164 0.6 100

1980–1986 Agriculture Developed 50 23 15.9 0.2 32.7

Wetland Water 20 16 11.0 0.1 13.1

Forest Mechanically disturbed 12 13 8.8 0.0 7.8

Agriculture Grassland/Shrubland 12 6 4.1 0.0 7.5

Forest Agriculture 10 4 2.9 0.0 6.2

Other Other 50 n/a n/a 0.2 32.6

Totals 154 0.6 100

1986–1992 Agriculture Developed 70 36 24.5 0.3 30.2

Agriculture Forest 25 27 18.3 0.1 11.0

Forest Developed 20 15 10.4 0.1 8.7

Agriculture Grassland/Shrubland 20 11 7.7 0.1 8.6

Wetland Water 15 10 6.6 0.1 6.5

Other Other 81 n/a n/a 0.3 35.1

Totals 231 0.8 100

1992–2000 Agriculture Developed 100 39 26.6 0.4 33.0

Forest Mechanically disturbed 39 34 23.3 0.1 12.8

Water Wetland 37 24 16.5 0.1 12.3

Forest Developed 26 23 15.9 0.1 8.6

Grassland/Shrubland Forest 14 10 6.9 0.1 4.7

Other Other 87 n/a n/a 0.3 28.7

Totals 303 1.1 100

1973–2000

(overall)

Agriculture Developed 277 111 75.6 1.0 32.5

Water Wetland 69 47 31.9 0.3 8.1

Forest Developed 68 51 34.8 0.2 7.9

Forest Mechanically disturbed 66 62 42.1 0.2 7.7

Agriculture Grassland/Shrubland 50 21 14.4 0.2 5.9

Other Other 322 n/a n/a 1.2 37.8

Totals 851 3.1 100
96 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

References Cited

Frey, W.H., 2012, Population growth in metro America since 

1980—Putting the volatile 2000s in perspective: Washington, 

D.C., Metropolitan Policy Program at Brookings, 28 p., 

accessed December 31, 2012, at http://www.brookings.edu/~/

media/research/files/papers/2012/3/20%20population%20

frey/0320_population_frey.

Michigan Land Use Leadership Council, 2003, Michigan’s 

land, Michigan’s future—Final report of the Michigan 

Land Use Leadership Council: Michigan Land Use 

Leadership Council, accessed August 15, 2010, at 

http://michigan.gov/documents/MLULC_FINAL_

REPORT_0803_77503_7.pdf.

Omernik, J.M., 1987, Ecoregions of the conterminous United 

States: Annals of the Association of American Geographers, 

v. 77, no. 1, p. 118–125.

U.S. Environmental Protection Agency, 2002, Primary 

distinguishing characteristics of Level III ecoregions of the 

continental United States: U.S. Environmental Protection 

Agency, 20 p., accessed December 17, 2012, at ftp://ftp.epa.

gov/wed/ecoregions/us/Eco_Level_III_descriptions.doc.

Vogelmann, J.E., Howard, S.M., Yang, L., Larson, C.R., Wylie, 

B.K., and van Driel, N., 2001, Completion of the 1990s 

National Land Cover Data Set for the conterminous United 

States from Landsat Thematic Mapper data and ancillary 

data sources: Photogrammetric Engineering & Remote 

Sensing, v. 67, p. 650–662.

Wiken, E., Jiménez Nava, F., and Griffith, G., 2011, North 

American terrestrial ecoregions—Level III: Montreal, 

Canada, Commission for Environmental Cooperation, 

149 p., accessed October 31, 2012. at http://www.cec.org/

Storage/133/15860_QA07.30-32_NP_NA_Terrestrial_

Ecoregions_Level_3_Final-2june11.pdf.
Chapter 9

Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000 

Edited by Roger F. Auch and Krista A. Karstensen 

U.S. Geological Survey Professional Paper 1794–C, 2015

Eastern Corn Belt Plains Ecoregion

By Roger F. Auch

Ecoregion Description 

The Eastern Corn Belt Plains 

Ecoregion covers about 83,533 km2

(32,252 mi2), mainly in central 

Indiana, western and central Ohio, 

and southeastern Michigan but also in 

an extremely small part of Kentucky. 

The ecoregion is roughly rectangular 

in shape, except for the narrow band 

that extends northeast away from Fort 

Wayne, Indiana, into Michigan, and 

a southern part that extends southsoutheast of Indianapolis, Indiana, to 

the suburbs of Louisville, Kentucky, 

that lie near the Ohio River (fig. 1). 

Neighboring ecoregions include 

the Southern Michigan/Northern 

Indiana Drift Plains and Huron/

Erie Lake Plains Ecoregions to the 

north, the Eastern Great Lakes and 

Hudson Lowlands Ecoregion to the 

extreme northeast, the Erie Drift 

Figure 1. Map of Eastern Corn Belt

Plains Ecoregion and surrounding 

ecoregions, showing land-use/

land-cover classes from 1992 National 

Land Cover Dataset (Vogelmann and 

others, 2001); note that not all land-use/

land-cover classes shown in explanation 

may be depicted on map; note also that, 

for this “Status and Trends of Land Change” study, transitional 

land-cover class was subdivided into mechanically disturbed 

and nonmechanically disturbed classes. Squares indicate 

locations of 10 x 10 km sample blocks analyzed in study. Index 

map shows locations of geographic features mentioned in 

text. Abbreviations for Midwest–South Central United States 

ecoregions are listed in appendix 2. Also shown are parts of 

three Eastern United States ecoregions: Eastern Great Lakes 

and Hudson Lowlands (EGLHL), Interior Plateau, and Western 

Allegheny Plateau (WAP). See appendix 3 for definitions of landuse/land-cover classifications.

85° 84° 83° 82° 87° 86°

42°

41°

40°

39°

38°

Interior

Plateau

Southern Michigan/

 Northern Indiana

Drift Plains

Huron/Erie

Lake Plains

WAP

Interior

River

Lowland

Erie

Drift

Plains

CA

WAP

Central

Corn Belt

Plains

EGLHL

LAKE

LAKE ERIE

MICHIGAN

CANADA

0 50 MILES

0 50 KILOMETERS

Ecoregion boundary

Sample block (10 x 10 km)

Land-use/land-cover class

Water

Developed

Transitional

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Ice/Snow

EXPLANATION

SCIOTO

MARSH

(HISTORICAL)

Fort Wayne

Indianapolis

Madison

Decatur

Louisville

Kokomo

Columbus

Wilmington

Marysville

Dayton

Cincinnatti

Marion

Findlay

Bucyrus Alger

INDIANA

OHIO

KENTUCKY ILLINOIS

MICHIGAN

Crawfordsville

HARDIN

COUNTY

MADISON

COUNTY

JEFFERSON

COUNTY

L A K E

M I C H I G A N

LAKE ERIE

CANADA

MONTGOMERY COUNTY

O h i o Ri v e r

IN

MI

OH

Eastern Corn

Belt Plains

Ecoregion
98 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Plains and Western Allegheny Plateau Ecoregions to the east, 

the Interior Plateau Ecoregion to the south, the Interior River 

Lowland Ecoregion to the southwest, and the Central Corn Belt 

Plains Ecoregion to the west. The climate is considered warm 

temperate and fully humid. Average annual precipitation ranges 

from 816 to 1,080 mm (32–42.5 in.), with precipitation generally 

increasing from north to south (Woods and others, 1998). 

Glaciation has played a major role in shaping the landforms of 

the ecoregion, with more level and rolling Wisconsin-age till 

plains in the north and pre–Wisconsin-age deposits along the 

southern periphery (Woods and others, 1998). 

The land cover of the Eastern Corn Belt Plains Ecoregion at 

the turn of the 19th century was predominantly composed of forest. 

Upland forest consisted of American beech (Fagus grandifolia), 

mixed oak (Quercus spp.), and oak–sugar maple (Quercus spp.

and Acer saccharum, respectively) communities. Forest in wetter 

areas (forested wetlands) was composed of elm-ash (Ulmus spp. 

and Fraxinus spp., respectively) communities (Woods and others, 

1998). The land cover also included prairie grasslands, many of 

which were considered “wet prairies” where the soil remained 

saturated or inundated for much of the growing season. The soils 

under most of the forest and prairies were rich for agricultural use 

when the first European-American settlers arrived in the ecoregion 

during the first few decades of the 19th century.

Figure 2. Drainage systems in Eastern Corn Belt Plains 

Ecoregion. A, Typical drainage ditch (this one is in Madison County, 

Ohio), with outlet of tile drainage system in foreground. B, Larger 

and deeper drainage system, in Hardin County, Ohio, needed to 

convert former Scioto Marsh (historical) to fertile cropland in 1800s.

Figure 3. Corn and soybean crops growing in Eastern Corn Belt 

Plains Ecoregion. A, Corn growing on both sides of road, north 

of Kokomo, Indiana. B, Soybean field and typical farmstead in 

background, in Montgomery County, Indiana. 

Most of the original land covers of the Eastern Corn 

Belt Plains Ecoregion were converted to anthropogenic land 

uses during the 1800s, primarily to agriculture. Later in the 

19th century and continuing throughout the 20th century, 

conversions to developed increased, although, during the study 

period, agriculture remained the predominant land cover. The 

conversion of upland forest to agriculture or developed was 

straightforward, but the conversion of forested wetland areas 

or wet prairies took more effort. Wetter areas were drained in 

major reclamation efforts, using drain tiles and drainage ditches 

that, in many places, became a common landscape feature (figs. 

2A,B). Most of the wetland drainage was completed by the 

1920s, although it continued into the late 20th century (Prince, 

1997). Forest often remained along riparian watercourses in 

dissected upland areas such as along the southern periphery of 

the ecoregion, and some were kept as woodlots for landowner 

use. Many of these woodlots have unnatural geometrical shapes 

(for example, squares and rectangles).

Agriculture continued to occupy most of the Eastern 

Corn Belt Plains Ecoregion during the 27-year study period. 

The ecoregion is a national leader in corn and soybean 

production (figs. 3A,B), although other crops such as alfalfa 

A

A

B

B
Chapter 9—Eastern Corn Belt Plains Ecoregion 99

hay and wheat also are grown (figs. 4A,B). Livestock 

production primarily consisted of hogs (fig. 5) and, to a more 

limited extent, beef and dairy cattle. Agricultural land within 

the Eastern Corn Belt Plains Ecoregion also included small 

areas of intensively used pastureland. 

Forest and developed were secondary land covers 

found in the ecoregion during the study period. Patches 

of forest commonly were present across the agricultural 

landscape, but they usually were isolated from one another 

by farmland (fig. 6). Only along substantial riparian corridors 

would forest be more contiguous (fig. 7). Developed was 

present across a hierarchy of populated places, ranging from 

large metropolitan areas such as Indianapolis, Indiana, and 

Cincinnati, Dayton, and Columbus, Ohio; to medium-sized 

cities such as Fort Wayne, Indiana; to smaller micropolitan 

areas such as Findlay and Bucyrus, Ohio, and Madison, 

Decatur, and Marion, Indiana (figs. 8A,B,C). Most of these 

cities grew as manufacturing centers during the 19th and 

first half of the 20th centuries, although Columbus and 

Indianapolis also are state capitals. Exurban development was 

common on the fringes of these variously sized urban areas 

(figs. 9A,B). All other land-cover classes were very small at 

the ecoregion scale.

Figure 4. Alfalfa-hay and wheat crops growing in Eastern 

Corn Belt Plains Ecoregion. A, Large alfalfa field, northeast of 

Crawfordsville, Indiana. B, Wheat stubble next to corn field, 

southwest of Bucyrus, Ohio. 

Figure 5. Farmstead with large grain bins and several modern 

hog-confinement buildings, south of Fort Wayne, Indiana. 

Figure 6. Squared-off patch of forest amidst landscape of 

cultivated fields, in Madison County, central Ohio. 

Contemporary Land-Cover Change 

(1973 to 2000)

The overall spatial change (the percentage of land area 

that changed at least one time) in the Eastern Corn Belt 

Plains Ecoregion between 1973 and 2000 is estimated at 

6.3 percent (table 1). Compared to other Midwest–South 

Central United States ecoregions, the Eastern Corn Belt Plains 

Ecoregion was above median ranking (fig. 10), and it had 

more change than most of its neighboring ecoregions. About 

5.9 percent of the ecoregion changed only once during the 

study period, and 0.3 percent changed more than once (table 

1). Examples of multiple changes include areas once used 

for agriculture that reverted to grassland/shrubland and then 

to forest in the next time period or at a later date, as well as 

sites around metropolitan areas that experienced large-scale, 

active land disturbance related to development or preliminary 

construction in one time period, followed by subsequent 

time periods in which development either was completed 

or not finished. In the latter case, the land cover reverted to 

grassland/shrubland to be held as possible speculation for 

future development. 

The period between 1992 and 2000 had the greatest 

amount of change, whereas the period between 1980 and 1986 

A

B
100 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Figure 7. Riparian forest along stream, in western Jefferson 

County, Indiana. 

Figure 8. Developed land in Eastern Corn Belt Plains Ecoregion. 

A, Street scene in small town of Alger, Ohio. B, Fairly new highgrowth area north of Cincinnati, Ohio. C, Car manufacturing plant, 

built sometime during study period (1973–2000) just outside of 

Marysville, Ohio. 

Figure 9. Exurban development in Eastern Corn Belt Plains 

Ecoregion. A, Single-family (nonfarm) residence east of Decatur, 

Indiana, near Indiana-Ohio border. B, Exurban subdivision outside 

of Wilmington, Ohio. 

had the least amount of change (table 2). When the uneven 

time periods were normalized to an average annual rate of 

change, the period between 1986 and 1992 had the second 

highest change (0.3 percent), and the period between 1973 

and 1980 had the third highest change (0.2 percent). The last 

time period remained the period with the highest change (0.4 

percent), and the second time period had the lowest change 

(0.1 percent) (table 2; fig. 11).

The agriculture and developed land-cover classes 

experienced the most net change during the study period, 

and changes in both classes were closely linked. Agriculture 

decreased by an estimated 5.2 percent of the ecoregion 

(4,338km2, a 6.5 percent decrease from its estimated 1973 

level), and developed increased by an estimated 5.1 percent 

(4,245 km2, a 92.3 percent increase from its estimated 1973 

level) (table 3). Other, more minor net changes included 

forest decreasing by 0.5 percent (411 km2, a 3.8 percent 

change from its estimated 1973 level), grassland/shrubland 

increasing by 0.3percent (239 km2), and water increasing by 

0.2 percent of the ecoregion (126 km2) (table 3; fig. 12). 

Developed land increased during the study period 

(figs. 13A,B). Agricultural land was the main source of 

new developed land, contributing an estimated 3,708 km2, 

followed by forested land that was converted to developed 

land (403km2). A substantial amount of the new developed 

land (2,031 km2; table 3) was added during the last time 

period (1992–2000). Agriculture to developed was the leading 

A

A

B

B

C
Chapter 9—Eastern Corn Belt Plains Ecoregion 101

Figure 10. Overall spatial change in Eastern Corn Belt Plains 

Ecoregion (ECBP; darker bars) compared with that of all 17 

Midwest–South Central United States ecoregions (lighter bars). 

Each horizontal set of bars shows proportions of ecoregion that 

changed during one, two, three, or four time periods; highest level 

of spatial change in Eastern Corn Belt Plains Ecoregion (four time 

periods) labeled for clarity. See table 2 for years covered by each 

time period. See appendix 2 for key to ecoregion abbreviations.

0 12 24 36

Area, as percent of ecoregion

Ecoregion 

DA

HELP

CCBP

SMNIDP

NCHF

BM

IRL

SEWTP

OH

EDP

ECBP

NMW

AV

MAP

NLF

SCP

OM

EXPLANATION

Change in one time period

Change in two time periods

Change in three time periods

Change in four time periods

Change in four time periods

land-cover change in the Eastern Corn Belt Plains Ecoregion 

(table4; fig. 14).

Agriculture also changed to grassland/shrubland (388 

km2). The only notable source of new farmland was the 

conversion of 171 km2 of forest to agriculture. The change of 

agriculture to grassland/shrubland land cover in the Eastern 

Corn Belt Plains Ecoregion occurred mostly in smaller areas 

where farming had been discontinued and the land reverted 

to “brush” (grassland/shrubland) and then possibly to forest 

during the study period (fig. 15). However, the amount of land 

converted from agriculture to grassland/shrubland increased 

during the last two time periods (1986–1992, 1992–2000), a 

time when the federal Conservation Reserve Program (CRP) 

was in effect. Land enrolled in the CRP could return to 

agriculture, if desired, at a future date.

Land uses and land covers in the Eastern Corn Belt 

Plains Ecoregion remained mostly stable during the study 

period (1973–2000). Although agricultural land decreased 

Figure 11. Estimates of land-cover change per time period, 

normalized to annual rates of change for all 17 Midwest–South 

Central United States ecoregions (gray bars). Estimates of change 

for Eastern Corn Belt Plains Ecoregion are represented by red bars 

in each time period.

0.5

0.0

1.0

1.5

2.5

3.0

2.0

3.5

1973 to 1980 1980 to 1986 1986 to 1992 1992 to 2000

Average annual change, as percent of ecoregion

Time period

Figure 12. Normalized average net change in Eastern Corn Belt 

Plains Ecoregion by time period for each land-cover class. Bars 

above zero axis represent net gain, whereas bars below zero 

represent net loss. Note that not all land-cover classes shown 

in explanation may be represented in figure. See appendix 3 for 

definitions of land-use and land-cover classifications.

−4

−2

0

2

4

1973–1980 1980–1986 

Time period

1986–1992 1992–2000 

Area changed, as percent of ecoregion 

Water

Developed

Mechanically disturbed

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Nonmechanically disturbed

Ice/Snow

EXPLANATION

LAND-USE/LAND-COVER CLASS
102 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Figure 15. Conversion from agriculture to grassland/shrubland 

land cover that occurred southeast of metropolitan Cincinnati, Ohio, 

on southern margin of Eastern Corn Belt Plains Ecoregion.

Figure 14. Conversion from agriculture to developed land cover, 

most common type of change in Eastern Corn Belt Plains Ecoregion, 

that occurred on south side of metropolitan Indianapolis, Indiana. 

Figure 13. Developed land cover in Eastern Corn Belt Plains 

Ecoregion. A, New residential development across road from 

long-established rural cemetery, on northeast side of Indianapolis, 

Indiana, metropolitan area. B, New minimill steel plant that uses 

steel scrap for its feedstock, north-northeast of Fort Wayne, Indiana. 

by an estimated 5 percent of the ecoregion during the 

study period, it still remained by far the leading land cover, 

occupying an estimated 75 percent of the ecoregion in 2000. 

Agriculture was lost to developed, grassland/shrubland, 

mining, water, and forest land covers, but it was only 

noticeably replaced by forest land cover. Most losses of 

agricultural land were to newly developed land, which was 

the largest single type of change in the Eastern Corn Belt 

Plains Ecoregion, resulting in an estimated conversion of 

3,708 km2 (table 4). The last time period (1992–2000) had 

the most change from agriculture to developed: 1,760 km2, 

or annualized to 220 km2 per year. In a study of construction 

projects in 44 central Indiana counties (three-fourths of which 

were in the Eastern Corn Belt Plains Ecoregion, including 

the counties in the Indianapolis metropolitan area) during 

the 1990s, 59 percent were residential, 13.5 percent were 

commercial, 9 percent were in warehousing, 5 percent were 

in educational facilities, and 5 percent were in manufacturing, 

indicating sustained suburban growth in the ecoregion (Nunn, 

2002). In Ohio, the population of “fringe metropolitan 

counties” (that is, counties that are less urbanized than a 

core urban county but are closely linked to one) increased 

by 14 percent during the 1990s, compared to 2 percent in 

core urban counties (Clark and others, 2003), indicating 

continued deconcentration of urbanization in those parts of the 

ecoregion. 

A

B
Chapter 9—Eastern Corn Belt Plains Ecoregion 103

Table 1. Percentage of Eastern Corn Belt Plains Ecoregion land 

cover that changed at least one time during study period (1973–

2000) and associated statistical error.

[Most sample pixels remained unchanged (93.7 percent), whereas 6.3 percent 

changed at least once throughout study period] 

Number

of

changes

Percent

of

ecoregion

Margin

of error

(+/− %)

Lower

bound

(%)

Upper

bound

(%)

Standard

error

(%)

Relative

error

(%)

1 5.9 2.5 3.4 8.4 1.7 29.0

2 0.3 0.2 0.2 0.5 0.1 32.6

3 0.0 0.0 0.0 0.0 0.0 45.9

4 0.0 0.0 0.0 0.0 0.0 76.7

Overall 

spatial 

change

6.3 2.7 3.6 8.9 1.8 28.7

Table 2. Raw estimates of change in Eastern Corn Belt Plains Ecoregion land cover, computed for each 

of four time periods between 1973 and 2000, and associated error at 85-percent confidence level.

[Estimates of change per period normalized to annual rate of change for each time period]

Period Total change

(% of ecoregion)

Margin of 

error

(+/− %)

Lower 

bound

(%)

Upper bound

(%)

Standard 

error

(%)

Relative 

error

(%)

Average rate

(% per year)

Estimate of change, in percent stratum

1973–1980 1.3 0.8 0.5 2.1 0.5 40.3 0.2

1980–1986 0.7 0.3 0.5 1.0 0.2 24.4 0.1

1986–1992 1.6 0.6 1.0 2.1 0.4 25.3 0.3

1992–2000 3.1 1.5 1.5 4.6 1.0 33.9 0.4

Estimate of change, in square kilometers

1973–1980 1,115 662 453 1,777 450 40.3 159

1980–1986 597 214 383 811 145 24.4 99

1986–1992 1,305 487 818 1,792 331 25.3 218

1992–2000 2,570 1,282 1,288 3,852 871 33.9 321
104 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Table 3. Estimated area (and margin of error) of each land-cover class in Eastern Corn Belt Plains Ecoregion, calculated 

five times between 1973 and 2000. See appendix 3 for definitions of land-cover classifications.

Water Developed

Mechanically 

disturbed

Mining Barren Forest Grassland/

Shrubland Agriculture Wetland

Nonmechanically 

disturbed

% +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/−

Area, in percent stratum

1973 0.6 0.3 5.5 1.8 0.0 0.0 0.1 0.0 0.0 0.0 13.0 2.3 0.1 0.0 80.2 3.2 0.4 0.2 0.0 0.0

1980 0.6 0.3 6.6 2.2 0.0 0.0 0.1 0.1 0.0 0.0 12.9 2.3 0.2 0.1 79.2 3.4 0.4 0.2 0.0 0.0

1986 0.6 0.3 7.0 2.3 0.0 0.0 0.1 0.1 0.0 0.0 12.9 2.3 0.2 0.1 78.7 3.5 0.4 0.2 0.0 0.0

1992 0.7 0.3 8.2 2.6 0.1 0.1 0.1 0.1 0.0 0.0 12.7 2.3 0.3 0.1 77.6 3.8 0.4 0.2 0.0 0.0

2000 0.7 0.3 10.6 3.6 0.2 0.1 0.1 0.1 0.0 0.0 12.5 2.3 0.4 0.1 75.0 4.6 0.4 0.2 0.0 0.0

Net

change 0.2 0.1 5.1 2.4 0.1 0.1 0.0 0.0 0.0 0.0 –0.5 0.4 0.3 0.1 –5.2 2.4 0.0 0.0 0.0 0.0

Gross

change 0.2 0.1 5.1 2.4 0.2 0.1 0.2 0.1 0.0 0.0 0.7 0.4 0.5 0.2 5.4 2.4 0.0 0.0 0.0 0.0

Area, in square kilometers

1973 493 219 4,598 1,471 29 27 54 39 2.7 3.2 10,890 1,910 101 40 67,005 2,675 361 177 0 0

1980 501 220 5,492 1,810 24 29 82 54 2.7 3.2 10,795 1,914 152 60 66,125 2,829 359 177 0 0

1986 516 225 5,869 1,945 11 12 88 50 2.7 3.3 10,779 1,914 155 53 65,752 2,936 361 177 0 0

1992 553 232 6,812 2,200 61 63 95 59 2.8 3.4 10,644 1,911 215 65 64,786 3,155 364 178 0 0

2000 619 261 8,843 3,039 131 93 83 47 6.7 9.0 10,479 1,913 340 111 62,667 3,873 364 178 0 0

Net

change 126 75 4,245 1,984 102 92 29 21 4.1 5.9 –411 316 239 93 –4,338 1,982 3 4 0 0

Gross

change 133 77 4,245 1,984 175 106 130 78 4.1 5.9 597 313 392 128 4,488 1,965 11 5 0 0
Chapter 9—Eastern Corn Belt Plains Ecoregion 105

Table 4. Principal land-cover conversions in Eastern Corn Belt Plains Ecoregion, showing amount of area changed (and margin 

of error, calculated at 85-percent confidence level) for each conversion during each of four time periods and also during overall 

study period. See appendix 3 for definitions of land-cover classifications.

[Values given for “other” class are combined totals of values for other land-cover classes not listed in that time period. Abbreviations: n/a, not applicable]

Period From class To class

Area 

changed

Margin of 

error

Standard 

error Percent of 

ecoregion

Percent of all 

changes (km2) (+/− km2) (km2)

1973–1980 Agriculture Developed 823 646 439 1.0 73.8

Agriculture Grassland/Shrubland 69 43 29 0.1 6.2

Forest Agriculture 65 28 19 0.1 5.8

Forest Developed 40 38 25 0.0 3.6

Mechanically disturbed Developed 29 27 18 0.0 2.6

Other Other 89 n/a n/a 0.1 8.0

Totals 1,115 1.3 100

1980–1986 Agriculture Developed 324 159 108.1 0.4 54.3

Grassland/Shrubland Forest 56 41 28.2 0.1 9.4

Agriculture Grassland/Shrubland 50 18 12.3 0.1 8.4

Forest Agriculture 44 21 14.3 0.1 7.3

Forest Developed 30 16 10.9 0.0 5.0

Other Other 93 n/a n/a 0.1 15.6

Totals 597 0.7 100

1986–1992 Agriculture Developed 801 336 228.3 1.0 61.4

Forest Developed 131 120 81.3 0.2 10.1

Agriculture Grassland/Shrubland 109 44 29.6 0.1 8.3

Agriculture Mechanically disturbed 56 59 40.2 0.1 4.3

Forest Agriculture 37 14 9.7 0.0 2.8

Other Other 171 n/a n/a 0.2 13.1

Totals 1,305 1.6 100

1992–2000 Agriculture Developed 1,760 896 608.7 2.1 68.5

Forest Developed 202 143 96.9 0.2 7.8

Agriculture Grassland/Shrubland 161 69 46.8 0.2 6.3

Agriculture Mechanically disturbed 125 90 61.2 0.1 4.8

Mechanically disturbed Developed 54 57 38.7 0.1 2.1

Other Other 269 n/a n/a 0.3 10.5

Totals 2,570 3.1 100

1973–2000

(overall)

Agriculture Developed 3,708 1,726 1,172.8 4.4 66.4

Forest Developed 403 303 205.6 0.5 7.2

Agriculture Grassland/Shrubland 388 134 91.2 0.5 7.0

Agriculture Mechanically disturbed 206 152 103.3 0.2 3.7

Forest Agriculture 171 45 30.4 0.2 3.1

Other Other 710 n/a n/a 0.9 12.7

Totals 5,587 6.7 100
106 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

References Cited

Clark, J., Sharp, J.S., Irwin, E., and Libby, L., 2003, Growth 

and change at the rural-urban interface—An overview 

of Ohio’s changing population and land use: Columbus, 

Ohio State University, The Exurban Change Project, 

Summary Report, 39 p., accessed February 24, 2013, at 

http://sri.osu.edu/sites/drupal-sri.web/files/growth%20

change%20full%20report.pdf. 

Nunn, S., 2002, Patterns of built investment in central 

Indiana 1990–99: Indianapolis, Indiana University, Center 

for Urban Policy and the Environment, 16 p., accessed 

February 26, 2013, at http://www.policyinstitute.iu.edu/

publicationDetail.aspx?PublicationID=55.

Prince, H., 1997, Wetlands of the American Midwest—A 

historical geography of changing attitudes: Chicago, The 

University of Chicago Press, 395 p.

Vogelmann, J.E., Howard, S.M., Yang, L., Larson, C.R., Wylie, 

B.K., and van Driel, N., 2001, Completion of the 1990s 

National Land Cover Data Set for the conterminous United 

States from Landsat Thematic Mapper data and ancillary data 

sources: Photogrammetric Engineering & Remote Sensing, v. 

67, p. 650–662.

Woods, A.J., Omernik, J.M., Brockman, C.S., Gerber, T.D., 

Hosteter, W.D., and Azevedo, S.H., 1998, Ecoregions of 

Indiana and Ohio: U.S. Geological Survey Ecoregion Map 

Series, scale 1:500,000, available at http://rockyweb.cr.usgs.

gov/outreach/mapcatalog/environmental.html.
Chapter 10

Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000 

Edited by Roger F. Auch and Krista A. Karstensen 

U.S. Geological Survey Professional Paper 1794–C, 2015

Central Corn Belt Plains Ecoregion 

By Daniel G. Sorenson

Ecoregion Description 

The Central Corn Belt Plains Ecoregion 

(Omernik, 1987; Wiken and others, 2011), which 

covers about 98,794 km2 (38,145 mi2), is bordered 

by (clockwise, from the northeast) the Southern 

Michigan/Northern Indiana Drift Plains, Eastern 

Corn Belt Plains, Interior River Lowland, Western 

Corn Belt Plains, Driftless Area, and Southeastern 

Wisconsin Till Plains Ecoregions (fig. 1). Most 

of the ecoregion is in the state of Illinois, but the 

ecoregion also extends into northwestern Indiana 

and southeastern Wisconsin (fig. 1). The northern 

border is at Racine, Wisconsin, where the ecoregion 

follows the southwestern shore of Lake Michigan 

to Gary, Indiana. To the west, the ecoregion extends 

to the Mississippi River at Moline, Illinois, and, 

to the east, it ends just north of Interstate 70 near 

Terre Haute, Indiana. Most of the ecoregion is 

covered by Wisconsin-age glaciated till, and its 

natural vegetation consists of extensive prairie 

communities intermixed with oak-hickory (Quercus

spp. and Carya spp., respectively) forests (Wiken 

and others, 2011). 

In the early 19th century, level upland areas 

were covered by tallgrass prairies composed 

of species such as big bluestem (Andropogon 

gerardii), little bluestem (Schizachyrium 

condensatum), Indiangrass (Sorghastrum nutans), 

and switchgrass (Panicum virgatum) (Woods 

Figure 1. Map of Central Corn Belt Plains Ecoregion 

and surrounding ecoregions, showing land-use/landcover classes from 1992 National Land Cover Dataset 

(Vogelmann and others, 2001); note that not all landuse/land-cover classes shown in explanation may be 

depicted on map; note also that, for this “Status and 

Trends of Land Change” study, transitional land-cover 

class was subdivided into mechanically disturbed and 

nonmechanically disturbed classes. Squares indicate locations of 10 x 10 km sample blocks analyzed in study. Index map shows 

locations of geographic features mentioned in text. Abbreviations for Midwest–South Central United States ecoregions are listed in 

appendix 2. Also shown are parts of two Great Plains ecoregions (Central Irregular Plains [CIP] and Western Corn Belt Plains [WCBP]) 

and one Eastern United States ecoregion (Interior Plateau). See appendix 3 for definitions of land-use/land-cover classifications.

Interior

River Lowland

Driftless

Area

WCBP

Eastern

Corn Belt Plains

Interior

Plateau

Central

Irregular

Plains

CIP

CIP

SMNIDP

SEWTP

Western

Corn Belt Plains

LAKE

MICHIGAN

91° 90° 89° 88° 87°

43°

42°

41°

40°

39°

IL

WI

IN

MI

Central Corn

Belt Plains

Ecoregion

0 50 100 MILES

0 50 100 KILOMETERS

Ecoregion boundary

Sample block (10 x 10 km)

Land-use/land-cover class

Water

Developed

Transitional

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Ice/Snow

EXPLANATION

IOWA

MO

MI

Racine

Gary

Moline

Terre

Haute

Chicago

LAKE COUNTY

KANE

WILL COUNTY

DU

PAGE

Rockford

Peoria

Springfield Decatur

LAKE

MICHIGAN

ILLINOIS INDIANA

WISCONSIN

70

Mississ pi pi Riv er

Aurora

Naperville
108 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

and others, 2006). After the early 19th century, the native 

vegetation gradually was replaced by agricultural crops 

(Wiken and others, 2011). In 1820, about 59 percent of 

Illinois was prairie, and 37.5 percent was forest (Iverson, 

1988). By 2000, about 76 percent of Illinois was agricultural 

land, and only 11.5 percent was forest (Illinois Interagency 

Landscape Classification Project, 2002). The predominant 

crops grown today (2014) are corn and soybeans (figs. 2,3), 

but forage for livestock also is cultivated. Hogs and pigs are 

the predominant livestock, with some beef and dairy cattle, 

sheep, and poultry; however, livestock does not have as 

much of an economic effect on the Central Corn Belt Plains 

Ecoregion as it does in surrounding ecoregions (Woods and 

others, 2006).

Soils in the Central Corn Belt Plains Ecoregion typically 

are dark and rich, formed beneath the tallgrass prairies. On 

the broad, flat upland areas, Mollisols are common, especially 

on loess-covered till, whereas on the forested slopes and 

ridges, Alfisols are common (Omernik and Gallant, 1988). 

Poorly drained soils, ponds, and marshes were common in 

0 12 24 36

Area, as percent of ecoregion

Ecoregion 

DA

HELP

CCBP

SMNIDP

NCHF

BM

IRL

SEWTP

OH

EDP

ECBP

NMW

AV

MAP

NLF

SCP

OM

EXPLANATION

Change in one time period

Change in two time periods

Change in three time periods

Change in four time periods

Change in four time periods

Figure 2. Typical corn field in northern Illinois.

Figure 3. Soybeans, a major crop in Central Corn Belt Plains 

Ecoregion.

Figure 4. Overall spatial change in Central Corn Belt Plains 

Ecoregion (CCBP; darker bars) compared with that of all 17 

Midwest–South Central United States ecoregions (lighter bars). 

Each horizontal set of bars shows proportions of ecoregion that 

changed during one, two, three, or four time periods; highest level 

of spatial change in Central Corn Belt Plains Ecoregion (four time 

periods) labeled for clarity. See table 2 for years covered by each 

time period. See appendix 2 for key to ecoregion abbreviations.

the early 19th century, especially on low-lying, flat lands. 

As the ecoregion was developed for agriculture, much of 

these areas were tilled, ditched, and connected to drainage 

systems, eliminating much of the once-plentiful aquatic 

habitats (Woods and others, 2006). Elevations range from 

about 122 m in the south to about 305 m on a few hills in the 

north (Omernik and Gallant, 1988). The average length of the 

growing season varies from 160 days in the north to about 

180 days in the south (Angel, 2002). Most of the precipitation 

falls during the growing season, with average annual 

precipitation ranging from 813 to 1,117 mm (32–44in.)

(Omernik and Gallant, 1988). 

The Central Corn Belt Plains Ecoregion is highly 

populated, with a 2000 population of about 12.1 million. The 

most densely populated part of the ecoregion is adjacent to 

Lake Michigan and includes the city of Chicago, Illinois. 

Chicago is the largest city in the ecoregion, with a 2000 

population of 2,896,016. However, many small- to mediumsized cities are scattered throughout the ecoregion, most 

notably (2000 populations) Rockford, Illinois (150,115); 

the Chicago suburbs of Aurora (142,115) and Naperville 

(128,358), Illinois; Peoria (112,892), Springfield (111,454), 

and Decatur (81,860), Illinois; and Gary, Indiana (102,746) 

(U.S. Census Bureau, 2000).
Chapter 10—Central Corn Belt Plains Ecoregion 109

0.5

0.0

1.0

1.5

2.5

3.0

2.0

3.5

1973 to 1980 1980 to 1986 1986 to 1992 1992 to 2000

Average annual change, as percent of ecoregion

Time period

−2

−1

0

1

2

1973–1980 1980–1986 

Time period

1986–1992 1992–2000 

Area changed, as percent of ecoregion 

Water

Developed

Mechanically disturbed

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Nonmechanically disturbed

Ice/Snow

EXPLANATION

LAND-USE/LAND-COVER CLASS

Figure 5. Estimates of land-cover change per time period, 

normalized to annual rates of change for all 17 Midwest–South 

Central United States ecoregions (gray bars). Estimates of change 

for Central Corn Belt Plains Ecoregion are represented by red bars 

in each time period.

Figure 6. Normalized average net change in Central Corn Belt 

Plains Ecoregion by time period for each land-cover class. Bars 

above zero axis represent net gain, whereas bars below zero 

represent net loss. Note that not all land-cover classes shown 

in explanation may be represented in figure. See appendix 3 for 

definitions of land-use and land-cover classifications.

Contemporary Land-Cover Change

(1973 to 2000)

The overall spatial change (the percentage of land area 

that changed at least one time) in the Central Corn Belt Plains 

Ecoregion between 1973 and 2000 is estimated at 3.4 percent 

(table 1). Compared to other Midwest–South Central United 

States ecoregions, the Central Corn Belt Plains Ecoregion had one 

of the lowest amounts of change (fig. 4). Overall, an estimated 

3.2 percent of the ecoregion changed in one time period, and 0.2 

percent changed in two time periods (table 1). The amount of area 

that changed in either three or all four time periods was so small 

that it was statistically insignificant (table 1).

When normalized to account for the varying lengths of 

time periods, the estimated average annual change remained 

stable for the first three time periods, at 0.1 percent of the 

ecoregion, but increased in the last time period (table 2; fig.5). 

The amount of change was 0.7 percent (726 km2) between 

1973 and 1980 and 0.7 percent (713 km2) between 1980 and 

1986. The amount increased slightly between 1986 and 1992 

to 0.8 percent (784 km2), and it almost doubled (1.4 percent; 

1,352 km2) between 1992 and 2000 (tables 2,4).

Agriculture was the predominant land-cover class in 

the Central Corn Belt Plains Ecoregion. In 2000, agriculture 

constituted an estimated 75.3 percent of the ecoregion. Only two 

other land-cover classes were notable: developed, at 11.6percent,

and forest, at 9.3 percent. All other land-cover classes combined 

represented only 3.9 percent of the ecoregion (table3).

Most of the change in the Central Corn Belt Plains 

Ecoregion involved agriculture and developed land-cover 

classes, with conversions from agricultural land to developed 

land constituting the leading type of change in all time 

periods. Agriculture accounted for 75.4 percent of all changes 

that occurred in the ecoregion during the study period. The 

conversion from agriculture to developed made up 92.3percent

of all change from agriculture to another land-cover class 

(and 91.6 percent of all change of the developed land-cover 

class listed in table 4). Growth of the developed land-cover 

class stayed nearly constant between the first and second time 

periods, but it increased modestly during the third time period 

and doubled during the last time period (fig. 6).

The main story of land-use/land-cover change in the 

Central Corn Belt Plains Ecoregion between 1973 and 2000 

was the increase in developed land at the expense of agriculture 

(table 3; fig. 6). One of the primary drivers of change was 

the increase in population over the 27-year study period: the 

population for the ecoregion in 1970 was 10.5 million; by 

2000, the estimated population was 12.1 million, a 15.2 percent 

increase (U.S. Census Bureau, 2000). Much of this growth 

occurred in the suburbs of Chicago. The population increase 

for the counties surrounding Chicago between 1970 and 2000 
110 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

was about 61.0 percent for Kane County, 68.4 percent for Lake 

County, 83.7 percent for DuPage County, and 101.4 percent 

for Will County (U.S. Census Bureau, 2000). Between 1972 

and 1997, land that could be classified as urban in the Chicago 

suburbs increased by about 49 percent (Wang, 2002). The 

results of this study (table 4) also show an increased rate of new 

development in the 1990s (1992–2000) when compared to the 

earlier time periods.

One reason for the lower rate of development in the 

earlier time periods may have been the poor performance 

of the Illinois economy during the 1970s and early 1980s, 

although the slower rate of Illinois economic growth, when 

compared to the national rate, was more pronounced in 

the early 1980s than in the 1970s (Bryan, 1991). Some of 

the slower growth was attributed to Illinois’ larger (when 

compared to the rest of the United States) manufacturing base, 

such as metals and machinery. During this time, manufacturing 

decreased because of changes in technology, combined with 

more competition (and less demand) for manufactured goods 

from abroad. Other industries such as retail trade, finance, 

insurance, real estate, and services also grew more slowly 

when compared to national rates at this time. The high-wage, 

high-cost business climate, as well as the high tax rates in 

Illinois, may have encouraged the relocation of some of these 

industries to other regions in the United States such as the 

South and the West (Merriman and Yin, 2011). In the early 

1970s, meat packing, one of the most well known industries 

in Illinois, declined as the Chicago stockyards shut down. 

Direct sales of livestock from breeders to packers, along with 

the improvement of interstate trucking highways, changed 

the meat-packing industry: instead of shipping mature 

animals to the central stockyards, commercial feedlots were 

developed locally, and new packing plants were constructed 

nearby. In addition, large refrigerated trucks transported the 

products to supermarkets via the interstate-highway system, 

eliminating the need for large, urban stockyards to be located 

near railroads (Wade, 2005). From about 1985 to the early 

1990s, the gross state product, as well as employment and 

personal income levels, all stabilized (Bryan, 1991). With the 

stabilization of the Illinois economy, the rate of development 

increased (fig. 6).

The Illinois farm economy also performed poorly in the 

early 1980s. Between 1980 and 1986, Illinois lost thousands 

of farms and, with them, many farm jobs (Sander, 1989). 

Farm technologies and greater efficiencies made it possible 

to produce crops using less manpower. However, the new 

methods required extensive investment in modern tractors, 

grain storage, irrigation systems, and other technologies. 

Because the farm economy had prospered in the 1970s, many 

farmers borrowed heavily to pay for new equipment and 

land. During this time, farmers also had expanded their land 

because the demand for American agricultural commodities 

was high, and the weak dollar made American food products 

more affordable than in the past for other countries. Although 

interest rates were low and the cost of land was reasonable, 

this generally inflationary time caused interest rates and farm 

land values to rise rapidly by the end of the decade. However, 

in the 1980s the economy worsened. Foreign demand declined, 

especially after the grain embargo of the Soviet Union, and 

foreign competition grew. The value of the dollar increased, 

making American goods more expensive overseas. At the 

same time, domestic demand slowed because of the weakened 

economy. Farmers had trouble selling their products at the 

same prices as before, and when farm income declined, a farm 

financial crisis occurred. Furthermore, many farmers were 

saddled with high-interest loans tied mostly to devaluated land 

prices. Some farmers no longer could pay the debt they owed, 

and many of them lost their farms (Anderlik and Walser, 1999). 

Nevertheless, although the farm economy was weak and 

the amount of land in agricultural production had decreased 

(table 3), the production of corn and soybeans increased. In 

1973, Illinois produced 981,590,000 bushels of corn, but by 

2000 the number had increased to 1,668,550,000 bushels, 

a 70 percent gain (U.S. Department of Agriculture, 2011). 

The same type of increase can be seen for soybeans: in 1973, 

Illinois yielded 287,595,000 bushels of soybeans, but by 

2000 soybean production had increased by 59.9 percent to 

459,800,000 bushels (U.S. Department of Agriculture, 2011). 

Factors that may have contributed to the increase in crop 

yields were seed genetics, new producer-level management 

techniques, and—especially in the 1990s—favorable weather 

and growing conditions (Tannura and others, 2008).
Chapter 10—Central Corn Belt Plains Ecoregion 111

Table 1. Percentage of Central Corn Belt Plains Ecoregion land 

cover that changed at least one time during study period (1973–

2000) and associated statistical error.

[Most sample pixels remained unchanged (96.6 percent), whereas 3.4 percent 

changed at least once throughout study period] 

Number

of

changes

Percent

of

ecoregion

Margin

of error

(+/− %)

Lower

bound

(%)

Upper

bound

(%)

Standard

error

(%)

Relative

error

(%)

1 3.2 1.2 2.0 4.4 0.8 25.8

2 0.2 0.1 0.1 0.3 0.1 27.8

3 0.0 0.0 0.0 0.0 0.0 61.7

4 0.0 0.0 0.0 0.0 0.0 80.8

Overall 

spatial 

change

3.4 1.2 2.1 4.6 0.8 25.0

Table 2. Raw estimates of change in Central Corn Belt Plains Ecoregion land cover, computed for each 

of four time periods between 1973 and 2000, and associated error at 85-percent confidence level.

[Estimates of change per period normalized to annual rate of change for each period]

Period Total change

(% of ecoregion)

Margin of 

error

(+/− %)

Lower 

bound

(%)

Upper bound

(%)

Standard 

error

(%)

Relative 

error

(%)

Average rate

(% per year)

Estimate of change, in percent stratum

1973–1980 0.7 0.3 0.5 1.0 0.2 25.0 0.1

1980–1986 0.7 0.2 0.5 0.9 0.1 20.7 0.1

1986–1992 0.8 0.4 0.4 1.2 0.2 31.2 0.1

1992–2000 1.4 0.6 0.8 2.0 0.4 29.3 0.2

Estimate of change, in square kilometers

1973–1980 726 267 459 992 182 25.0 104

1980–1986 713 217 496 930 148 20.7 119

1986–1992 784 359 426 1,143 244 31.2 131

1992–2000 1,352 581 771 1,933 396 29.3 169
112 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Table 3. Estimated area (and margin of error) of each land-cover class in Central Corn Belt Plains Ecoregion, calculated five times 

between 1973 and 2000. See appendix 3 for definitions of land-cover classifications.

Water Developed

Mechanically 

disturbed

Mining Barren Forest Grassland/

Shrubland Agriculture Wetland

Nonmechanically 

disturbed

% +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/−

Area, in percent stratum

1973 1.6 0.8 9.2 4.3 0.0 0.0 0.2 0.1 0.0 0.0 9.5 2.0 0.7 0.3 77.4 6.0 1.4 0.9 0.0 0.0

1980 1.6 0.8 9.6 4.4 0.0 0.0 0.2 0.1 0.0 0.0 9.4 2.0 0.7 0.3 77.1 6.0 1.4 0.9 0.0 0.0

1986 1.5 0.8 10.0 4.5 0.0 0.0 0.2 0.1 0.0 0.0 9.3 2.0 0.7 0.3 76.8 6.0 1.5 1.0 0.0 0.0

1992 1.6 0.8 10.5 4.6 0.0 0.0 0.2 0.1 0.0 0.0 9.3 2.0 0.6 0.2 76.3 6.2 1.5 1.0 0.0 0.0

2000 1.6 0.8 11.6 4.9 0.0 0.0 0.3 0.1 0.0 0.0 9.3 2.0 0.6 0.2 75.3 6.3 1.4 1.0 0.0 0.0

Net

change 0.0 0.1 2.4 1.1 0.0 0.0 0.1 0.1 0.0 0.0 –0.2 0.1 –0.2 0.1 –2.2 1.1 0.1 0.1 0.0 0.0

Gross

change 0.2 0.2 2.4 1.1 0.1 0.1 0.2 0.1 0.0 0.0 0.5 0.1 0.4 0.1 2.5 1.1 0.2 0.2 0.0 0.0

Area, in square kilometers

1973 1,608 837 9,075 4,290 16 23 155 85 0 0 9,383 1,973 719 281 76,483 5,899 1,355 845 0 0

1980 1,545 780 9,464 4,341 2 3 179 94 0 0 9,290 1,968 733 275 76,155 5,949 1,426 936 0 0

1986 1,513 757 9,833 4,401 13 14 205 107 0 0 9,223 1,957 663 267 75,879 5,976 1,465 992 0 0

1992 1,547 776 10,347 4,573 15 17 218 113 0 0 9,216 1,944 608 246 75,411 6,101 1,433 957 0 0

2000 1,560 777 11,422 4,835 16 13 266 140 0 0 9,180 1,940 560 240 74,359 6,267 1,431 954 0 0

Net

change –48 126 2,347 1,118 0 27 111 66 0 0 –203 141 –159 89 –2,124 1,119 76 123 0 0

Gross

change 243 207 2,352 1,119 88 55 150 84 0 0 468 142 372 121 2,439 1,094 185 207 0 0
Chapter 10—Central Corn Belt Plains Ecoregion 113

Table 4. Principal land-cover conversions in Central Corn Belt Plains Ecoregion, showing amount of area changed (and margin 

of error, calculated at 85-percent confidence level) for each conversion during each of four time periods and also during overall 

study period. See appendix 3 for definitions of land-cover classifications.

[Values given for “other” class are combined totals of values for other land-cover classes not listed in that time period. Abbreviations: n/a, not applicable]

Period From class To class

Area 

changed

Margin of 

error

Standard 

error Percent of 

ecoregion

Percent 

of all 

changes (km2) (+/− km2) (km2)

1973–1980 Agriculture Developed 325 194 132 0.3 44.8

Forest Agriculture 83 45 31 0.1 11.4

Water Wetland 77 101 69 0.1 10.6

Agriculture Grassland/Shrubland 59 34 23 0.1 8.1

Forest Developed 43 28 19 0.0 5.9

Other Other 139 n/a n/a 0.1 19.1

Totals 726 0.7 100.0

1980–1986 Agriculture Developed 285 134 91 0.3 40.0

Forest Agriculture 69 46 31 0.1 9.7

Grassland/Shrubland Forest 51 36 25 0.1 7.2

Water Wetland 48 68 46 0.0 6.7

Forest Developed 46 44 30 0.0 6.4

Other Other 214 n/a n/a 0.2 30.0

Totals 713 0.7 100.0

1986–1992 Agriculture Developed 446 277 189 0.5 56.9

Grassland/Shrubland Forest 46 38 26 0.0 5.9

Agriculture Grassland/Shrubland 36 22 15 0.0 4.6

Wetland Water 36 47 32 0.0 4.6

Forest Developed 32 22 15 0.0 4.1

Other Other 188 n/a n/a 0.2 24.0

Totals 784 0.8 100.0

1992–2000 Agriculture Developed 983 533 363 1.0 72.7

Forest Developed 66 58 40 0.1 4.9

Grassland/Shrubland Forest 40 29 20 0.0 3.0

Agriculture Grassland/Shrubland 34 17 12 0.0 2.5

Mining Developed 31 24 16 0.0 2.3

Other Other 198 n/a n/a 0.2 14.6

Totals 1,352 1.4 100.0

1973–2000

(overall)

Agriculture Developed 2,039 1,023 697 2.1 57.0

Forest Agriculture 192 82 56 0.2 5.4

Forest Developed 187 126 86 0.2 5.2

Agriculture Grassland/Shrubland 171 79 54 0.2 4.8

Grassland/Shrubland Forest 162 89 61 0.2 4.5

Other Other 824 n/a n/a 0.8 23.0

Totals 3,575 3.6 100.0
114 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

References Cited

Anderlik, J.M., and Walser, J.W., 1999, Agriculture sector 

under stress—The 1980s and today: Federal Deposit 

Insurance Corporation, Kansas City Regional Outlook, 

Third Quarter 1999, accessed November 8, 2012, at http://

www.fdic.gov/bank/analytical/regional/ro19993q/kc/

agricult.html.

Angel, Jim, 2002, Illinois growing season: Champaign, 

University of Illinois, Illinois State Water Survey, State 

Climatologist Office for Illinois, accessed April 4, 2011, at 

http://www.isws.illinois.edu/atmos/statecli/Frost/growing_

season.htm.

Bryan, W.R., 1991, The Illinois economy: Champaign, 

University of Illinois, College of Business, Office of Real 

Estate Research Letter, p. 14–15, accessed November 8, 

2012, at http://business.illinois.edu/orer/V5-2-6.pdf.

Illinois Interagency Landscape Classification Project, 2002, 

Land cover of Illinois 1999–2000: Springfield, Illinois 

Department of Agriculture database, accessed April 1, 2011, 

at http://www.agr.state.il.us/gis/landcover99-00.html.

Iverson, L.R., 1988, Land-use changes in Illinois, USA—The 

influence of landscape attributes on current and historic land 

use: Landscape Ecology, v. 2, no. 1, p. 45–61.

Merriman, D., and Yin, X., 2011, Illinois economy—Past 

trends, current challenges, future prospects, in The Illinois 

Report 2011: Champaign, University of Illinois, Institute of 

Government and Public Affairs, p. 9–12, accessed March 

24, 2014, at http://igpa.uillinois.edu/IR11/Report/index.

html.

Omernik, J.M., 1987, Ecoregions of the conterminous United 

States: Annals of the Association of American Geographers, 

v. 77, p. 118–125.

Omernik, J.M., and Gallant, A.L., 1988, Ecoregions of the 

upper Midwest: Corvallis, Oreg., U.S. Environmental 

Protection Agency, Environmental Research Laboratory, 

EPA 600/3-88/037, 56 p.

Sander, W., 1989, Local taxes, schooling, and jobs in Illinois: 

Champaign, University of Illinois, College of Business, 

Office of Real Estate Research Letter, p. 6–7, accessed 

November 8, 2012, at http://business.illinois.edu/orer/

V3-4-3.pdf.

Tannura, M., Irwin, S., and Good, D., 2008, Are corn trend 

yields increasing at a faster rate?: Champaign, University 

of Illinois, Department of Agriculture and Consumer 

Economics, Marketing and Outlook Briefs, MOBR 08-02, 

accessed March 24, 2014, at http://www.farmdoc.illinois.

edu/marketing/mobr/mobr_08-02/mobr_08-02.html. 

U.S. Census Bureau, 2000, Census of population and housing: 

U.S. Census Bureau database, accessed April 4, 2011, at 

http://www.census.gov/prod/www/abs/decennial/index.htm.

U.S. Department of Agriculture, 2011, Quick stats: U.S. 

Department of Agriculture, National Agriculture Statistics 

Service database, accessed April 11, 2011, at http://www.

nass.usda.gov/Quick_Stats/.

Vogelmann, J.E., Howard, S.M., Yang, L., Larson, C.R., Wylie, 

B.K., and van Driel, N., 2001, Completion of the 1990s 

National Land Cover Data Set for the conterminous United 

States from Landsat Thematic Mapper data and ancillary data 

sources: Photogrammetric Engineering & Remote Sensing, 

v.67, p. 650–662.

Wade, C.W., 2005, Meatpacking: Chicago Historical Society, 

The Electronic Encyclopedia of Chicago, accessed June 

30, 2011, at http://www.encyclopedia.chicagohistory.org/

pages/804.html.

Wang, Y.O., 2002, Remote sensing and modeling in regional 

land cover change study, in Commission IV, Proceedings 

of the Symposium on Geospatial Theory, Processing and 

Applications, 2002, Ottawa, Canada: International Society 

for Photogrammetry and Remote Sensing, 5 p., accessed 

November 8, 2012, at http://www.isprs.org/proceedings/

XXXIV/part4/pdfpapers/182.pdf.

Wiken, E., Jiménez Nava, F., and Griffith, G., 2011, North 

American terrestrial ecoregions—Level III: Montreal, 

Canada, Commission for Environmental Cooperation, 

149 p., accessed October 31, 2012, at http://www.cec.org/

Storage/133/15860_QA07.30-32_NP_NA_Terrestrial_

Ecoregions_Level_3_Final-2june11.pdf.

Woods, A.J., Omernik, J.M., Perderson, C.L., and Moran, 

B.C., 2006, Level III and IV ecoregions of Illinois: U.S. 

Environmental Protection Agency, EPA/600/R-06/104, 

p. 8–10, available at http://www.epa.gov/wed/pages/

publications/authored/EPA600R-0610%20Ecoregions%20

of%20Illinois%20Woods.pdf.
Chapter 11

Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000 

Edited by Roger F. Auch and Krista A. Karstensen 

U.S. Geological Survey Professional Paper 1794–C, 2015

Interior River Lowland Ecoregion 

By Krista A. Karstensen and Roger F. Auch

Ecoregion Description 

The Interior River Lowland 

Ecoregion encompasses 93,272 km2

(36,012 mi2), mainly in southern and 

western Illinois, but it also extends into 

southwestern Indiana, northwestern 

Kentucky, eastern Missouri, and a 

tiny part of southeastern Iowa (fig. 1) 

(Omernik, 1987; U.S. Environmental 

Protection Agency, 1999). The 

ecoregion is bordered by eight other 

ecoregions: the Central Corn Belt 

Plains Ecoregion to the north, the 

Eastern Corn Belt Plains Ecoregion 

to the northeast, the Interior Plateau 

Ecoregion to the east and southeast, the 

Figure 1. Map of Interior River Lowland 

Ecoregion and surrounding ecoregions, 

showing land-use/land-cover classes from 

1992 National Land Cover Dataset (Vogelmann 

and others, 2001); note that not all land-use/

land-cover classes shown in explanation 

may be depicted on map; note also that, for 

this “Status and Trends of Land Change” 

study, transitional land-cover class was 

subdivided into mechanically disturbed and 

nonmechanically disturbed classes. Squares 

indicate locations of 10x10 km sample

blocks analyzed in study. Index map shows 

locations of geographic features mentioned 

in text. Abbreviations for Midwest–South 

Central United States ecoregions are listed 

in appendix 2. Also shown are parts of two 

Great Plains ecoregions (Western Corn 

Belt Plains [WCBP] and Central Irregular 

Plains) and two Eastern United States 

ecoregions (Mississippi Valley Loess Plains 

[MVLP] and Interior Plateau). See appendix 

3 for definitions of land-use/land-cover 

classifications.

90° 89° 88° 87°

90° 89° 88° 87°

92° 91°

41°

40°

39°

38°

37°

Central

Corn Belt Plains

Ozark Highlands

Interior Plateau

WCBP

Central

Irregular

Plains

Eastern

Corn Belt

Plains

MAP

MVLP

SMNIDP

0 50 75 MILES

0 50 75

25

25 KILOMETERS

Ecoregion boundary

Sample block (10 x 10 km)

Land-use/land-cover class

Water

Developed

Transitional

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Ice/Snow

EXPLANATION

ILLINOIS

INDIANA

MISSOURI

IOWA

KENTUCKY

ST. CHARLES COUNTY

PERRY

COUNTY

Saint Louis

Owensboro

Evansville

Henderson

Terre Haute

Quincy

Paducah

Vincennes

Carbondale

Pocahontas

Whi t e River

W a b a s h

R i v e r

M i s s i s s i p p i R i v e r

M issouri R i v e r

I l l i n o i s R i v e r

Oh i o R i v e r

IL

IA

MO

IN

KY

Interior

River

Lowland

Ecoregion
116 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Figure 2. Forest and prairie landscapes in Interior River Lowland 

Ecoregion. A, Mostly forested landscape among woody bluffs 

southwest of Carbondale, Illinois, east of Mississippi River. B, 

Native-prairie restoration east of Vincennes, Indiana. 

Figure 3. Different farming conditions in Interior River Lowland 

Ecoregion, primarily resulting from local differences in topography. 

A, Corn fields in irregular landscape, just north of Pocahontas, 

Missouri. B, Flat field near farmstead in Perry County, Illinois, 

showing soybeans emerging from stubble that remains from 

previous harvest.

Mississippi Valley Loess Plains and the Mississippi Alluvial 

Plain Ecoregions to the south, the Ozark Highlands Ecoregion 

to the southwest, the Central Irregular Plains Ecoregion to the 

west, and the Western Corn Belt Plains Ecoregion to the far 

northwest. The Interior River Lowland Ecoregion includes a 

large stretch of the Mississippi River, and its confluences with 

the Missouri and Illinois Rivers are located in the ecoregion, 

as is the confluence of the Wabash River with the Ohio River. 

In addition, the Ohio–Mississippi River confluence lies just 

outside the southern part of the ecoregion. 

The Interior River Lowland Ecoregion is underlain by 

noncalcareous, clastic sedimentary rocks and deposits (Woods 

and others, 1998). The unstratified glacial deposits found north 

of the White River in Indiana indicate that pre–Wisconsin-age 

ice once covered much of the Interior River Lowland 

Ecoregion. Geomorphic characteristics also include terraced 

valleys filled with alluvium, as well as glacial-outwash, eolian, 

and lacustrine deposits (Woods and others, 1998). The 

ecoregion has a midlatitude continental climate, with hot 

summers and cold winters. Mean annual precipitation ranges 

from 860 to 1,320 mm (34–52 in.), depending on location 

(Wiken and others, 2011). Natural vegetation is composed 

primarily of bottomland and upland forests (fig. 2A), although 

in places the vegetation mosaic includes prairie grasslands 

(fig. 2B) that are dominated by bluestem grasses (for example, 

Andropogon gerardii and Schizachyrium scoparium), in 

addition to areas of herbaceous marshes (Woods and others, 

2006). Bottomland forests include sweetgum (Liquidambar 

styraciflua) and various oak species that thrive in wetter 

environments (for example, pin oak [Quercus palustris], 

swamp white oak [Quercus bicolor]); along the Mississippi 

River, a greater variety of trees can be found, including silver 

maple (Acer saccharinum), American elm (Ulmus Americana), 

green ash (Fraxinus pennsylvanica), sycamore (Platanus 

occidentalis), honey locust (Gleditsia triacanthos), black 

walnut (Juglans nigra), and hickory (Carya spp.). Upland 

forests include other types of oaks (for example, post oak 

[Quercus stellata], white oak [Quercus alba], black oak 

[Quercus velutina]), as well as shagbark hickory (Carya 

ovata) and, in more mesic sites, yellow-poplar (Liriodendron 

tulipifera), American beech (Fagus grandifolia), sugar maple 

(Acer saccharum), and northern red oak (Quercus rubra) 

(Wiken and others, 2011).

A

B

A

B
Chapter 11—Interior River Lowland Ecoregion 117

Figure 4. Coal mining, still operating in 2003 in some areas of 

Interior River Lowland Ecoregion, such as this one located in 

southwestern Indiana.

0 12 24 36

Area, as percent of ecoregion

Ecoregion 

DA

HELP

CCBP

SMNIDP

NCHF

BM

IRL

SEWTP

OH

EDP

ECBP

NMW

AV

MAP

NLF

SCP

OM

EXPLANATION

Change in one time period

Change in two time periods

Change in three time periods

Change in four time periods

Change in four time periods

Figure 5. Overall spatial change in Interior River Lowland 

Ecoregion (IRL; darker bars) compared with that of all 17 

Midwest–South Central United States ecoregions (lighter bars). 

Each horizontal set of bars shows proportions of ecoregion that 

changed during one, two, three, or four time periods; highest level 

of spatial change in Interior River Lowland Ecoregion (four time 

periods) labeled for clarity. See table 2 for years covered by each 

time period. See appendix 2 for key to ecoregion abbreviations.

0.5

0.0

1.0

1.5

2.5

3.0

2.0

3.5

1973 to 1980 1980 to 1986 1986 to 1992 1992 to 2000

Average annual change, as percent of ecoregion

Time period

Figure 6. Estimates of land-cover change per time period, 

normalized to annual rates of change for all 17 Midwest–South 

Central United States ecoregions (gray bars). Estimates of change 

for Interior River Lowland Ecoregion are represented by red bars 

in each time period.

Although land use in the Interior River Lowland 

Ecoregion is more varied than that of neighboring ecoregions 

(Woods and others, 1998), agricultural land use historically 

has been a vital economic resource for this ecoregion. The 

drained alluvial soils are farmed for feed grains and soybeans, 

whereas the valley upland areas are used for forage crops, 

pasture, and woodlots that support mixed uses of farming 

livestock and crop production (Woods and others, 1998) 

(fig. 3). This ecoregion provides a key component of national 

energy resources, as it contains the second largest coal reserve 

and the largest reserve of bituminous coal in the United States 

(Varanka and Shaver, 2007); however, use of this coal has 

diminished recently because of its high sulfur content (Milici 

and Dennen, 2009) (fig. 4). Developed land in the Interior 

River Lowland Ecoregion was dominated by (2000 

populations) the Saint Louis, Missouri (2,603,607), 

Evansville, Indiana–Henderson, Kentucky (296,195), and 

Terre Haute, Indiana (149,192), metropolitan areas, along with 

smaller cities that had populations of less than 100,000 

(Paducah and Owensboro, Kentucky, and Quincy, Illinois) 

(Demographia, 2003). 

Contemporary Land-Cover Change 

(1973 to 2000)

The overall spatial change (the percentage of land 

area that changed at least one time) in the Interior Lowland 

Ecoregion between 1973 and 2000 is estimated at 5.5 percent 

(table 1). Compared to other Midwest–South Central United 

States ecoregions, change in the Interior Lowland Ecoregion 

was moderate (fig. 5): an estimated 5 percent of the ecoregion 

changed in one time period. However, the percentage of the 

ecoregion that changed multiple times was low: about 0.5 

percent of the area changed twice, and 0.1 percent changed 

three times (table 1).
118 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

−2

−1

0

1

2

1973–1980 1980–1986 

Time period

1986–1992 1992–2000 

Area changed, as percent of ecoregion 

Water

Developed

Mechanically disturbed

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Nonmechanically disturbed

Ice/Snow

EXPLANATION

LAND-USE/LAND-COVER CLASS

Figure 8. Normalized average net change in Interior River 

Lowland Ecoregion by time period for each land-cover class. Bars 

above zero axis represent net gain, whereas bars below zero 

represent net loss. Note that not all land-cover classes shown 

in explanation may be represented in figure. See appendix 3 for 

definitions of land-use and land-cover classifications.

Figure 7. New housing development near Missouri River, part of 

metropolitan Saint Louis area in St. Charles County, Missouri.

The estimated area that changed in the ecoregion was 

highest between 1973 and 1980 (1.8 percent), and it slowly 

decreased until a slight peak was reached between 1992 and 

2000 (1.7 percent) (table 2). When normalized to an annual 

rate to account for unequal time periods, land-cover change 

still was highest between 1973 and 1980 (0.3 percent). The 

remaining time periods had an annual rate of change of 0.2 

percent (table 2; fig. 6). During the entire 27-year study period, 

conversions from forest to agriculture and from agriculture to 

developed were predominant (table 4).

Agriculture was the primary land-cover class in the 

ecoregion, increasing to an estimated 65.0 percent of the 

ecoregion by 1986 but decreasing marginally to 64.6 percent 

by 2000 (table 3); however, cropland use was highly intensive, 

and urbanization was expanding, driven by several economic 

sectors and industries (Varanka and Shaver, 2007). Forest 

was the next highest land-cover class in the ecoregion, with 

estimated values of 22.7 percent in 1973 and 20.4 percent in 

2000. Developed had a small but steady increase, from 5.4 

percent in 1973 to 7.0 percent in 2000 (table 3).

Developed expanded the most in the ecoregion, with an 

estimated increase of 1.6 percent (1,503 km2, a 30-percent 

net increase from its estimated 1973 level) between 1973 and 

2000 (table 3; fig. 7). Initially, developed expanded slowly 

(fig. 8) before peaking with the greatest rate of expansion 

between 1992 and 2000, which also was the period with the 

second highest overall amount of change (1.7 percent; table 2). 

The largest net decrease occurred in forest, with an estimated 

net decrease of 2.3 percent (2,114 km2, a 10-percent net 

decrease from its estimated 1973 level); forest primarily was 

cleared for agricultural expansion (fig. 9). 

Overall, the greatest change during the study period 

was the conversion from forest to agriculture (2,113 km2). 

However, this conversion did not result in a substantial net 

increase in agriculture because, during the same time period, 

agriculture was converting to developed. Conversion from 

agriculture to developed was the second most common change 

(1,186 km2). The loss of agriculture was masked by a low net 

amount of change (0.7 percent).

During the study period, the Interior River Lowland 

Ecoregion was a rich natural environment that had a low-tomoderate demand for competing land uses, which maintained 

the stability and growth of the ecoregion despite a relatively 

small population change (Varanka and Shaver, 2007). 

Although increased urbanization was one of the primary 

reasons for change in the ecoregion, population may not have 

been the only driver of change for the developed land-cover 

class. Similar to population patterns in other cities in the 

Midwest–South Central United States (for example, Chicago, 

Illinois, and Cleveland, Ohio), population growth in Saint 

Louis, Missouri, decreased during the study period, despite an 

increase in metropolitan land area. This pattern is indicative 

of the socioeconomic and demographic drivers of land 

change that played an integral role in the net increases of the 

developed land-cover class in the ecoregion. 
Chapter 11—Interior River Lowland Ecoregion 119

Figure 9. Landsat imagery of area about 10 km south of Owensboro, Kentucky, showing changes in land-cover class from forest (dark 

reds) to agriculture (greens and blues). Note that these are early Landsat (MSS) images and, thus, are of lower visual quality because 

of their coarser resolution. A, Image from late September 1972, showing large areas of forest and mostly harvested farm fields that 

surround them. B, Image from late September 1981 of same area as A, showing that forested areas have been cleared and converted to 

agricultural use, especially in northeastern part of image but also in several other parts of image. 

Table 1. Percentage of Interior River Lowland Ecoregion land 

cover that changed at least one time during study period (1973–

2000) and associated statistical error.

[Most sample pixels remained unchanged (94.5 percent), whereas 5.5 percent 

changed at least once throughout study period] 

Number

of

changes

Percent

of

ecoregion

Margin

of error

(+/− %)

Lower

bound

(%)

Upper

bound

(%)

Standard

error

(%)

Relative

error

(%)

1 5.0 1.4 3.6 6.3 0.9 18.7

2 0.5 0.2 0.3 0.7 0.2 30.7

3 0.1 0.0 0.0 0.1 0.0 38.1

4 0.0 0.0 0.0 0.0 0.0 72.2

Overall 

spatial 

change

5.5 1.5 4.0 7.0 1.0 18.2

A B
120 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Table 2. Raw estimates of change in Interior River Lowland Ecoregion land cover, computed for each of 

four time periods between 1973 and 2000, and associated error at 85-percent confidence level.

[Estimates of change per period normalized to annual rate of change for each period]

Period Total change

(% of ecoregion)

Margin of 

error

(+/− %)

Lower 

bound

(%)

Upper bound

(%)

Standard 

error

(%)

Relative 

error

(%)

Average rate

(% per year)

Estimate of change, in percent stratum

1973–1980 1.8 0.7 1.1 2.5 0.5 26.2 0.3

1980–1986 1.4 0.4 1.0 1.8 0.3 19.4 0.2

1986–1992 1.2 0.4 0.8 1.6 0.3 22.0 0.2

1992–2000 1.7 0.7 1.1 2.4 0.5 26.8 0.2

Estimate of change, in square kilometers

1973–1980 1,712 659 1,053 2,372 449 26.2 245

1980–1986 1,277 364 913 1,641 248 19.4 213

1986–1992 1,095 353 742 1,449 241 22.0 183

1992–2000 1,631 643 988 2,274 438 26.8 204

Table 3. Estimated area (and margin of error) of each land-cover class in Interior River Lowland Ecoregion, calculated five times 

between 1973 and 2000. See appendix 3 for definitions of land-cover classifications.

Water Developed

Mechanically 

disturbed

Mining Barren Forest Grassland/

Shrubland Agriculture Wetland

Nonmechanically 

disturbed

% +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/−

Area, in percent stratum

1973 2.6 0.8 5.4 3.0 0.1 0.1 0.1 0.1 0.0 0.0 22.7 3.4 0.5 0.3 64.0 3.9 4.6 1.3 0.0 0.0

1980 2.7 0.8 5.8 3.2 0.1 0.1 0.1 0.1 0.0 0.0 21.8 3.4 0.4 0.3 64.6 3.9 4.5 1.3 0.0 0.0

1986 2.7 0.8 6.0 3.3 0.0 0.0 0.1 0.1 0.0 0.0 21.1 3.4 0.4 0.3 65.0 4.0 4.5 1.3 0.0 0.0

1992 2.7 0.8 6.2 3.3 0.0 0.0 0.2 0.2 0.0 0.0 20.7 3.4 0.4 0.3 65.1 4.0 4.5 1.3 0.0 0.0

2000 2.8 0.8 7.0 3.6 0.0 0.0 0.1 0.1 0.0 0.0 20.4 3.4 0.4 0.3 64.6 4.1 4.6 1.3 0.0 0.0

Net

change 0.2 0.1 1.6 1.2 –0.1 0.1 0.0 0.1 0.0 0.0 –2.3 0.7 –0.1 0.2 0.7 1.3 0.0 0.2 0.0 0.0

Gross

change 0.3 0.1 1.6 1.2 0.3 0.2 0.5 0.4 0.0 0.0 2.8 0.7 0.4 0.2 3.6 1.1 0.3 0.2 0.0 0.0

Area, in square kilometers

1973 2,463 760 5,008 2,829 103 71 118 110 15 13 21,164 3,214 470 251 59,682 3,622 4,248 1,224 0 0

1980 2,516 769 5,400 2,967 81 71 92 86 15 13 20,307 3,189 413 259 60,210 3,652 4,238 1,224 0 0

1986 2,523 761 5,580 3,034 30 19 128 97 15 13 19,726 3,180 396 244 60,662 3,687 4,211 1,217 0 0

1992 2,563 758 5,816 3,104 20 15 222 187 17 15 19,285 3,136 417 241 60,719 3,692 4,213 1,219 0 0

2000 2,616 757 6,511 3,311 15 9 100 65 22 20 19,050 3,131 408 244 60,299 3,850 4,250 1,252 0 0

Net

change 153 106 1,503 1,088 –88 69 –18 95 7 8 –2,114 646 –62 164 617 1,175 2 156 0 0

Gross

change 259 99 1,521 1,088 323 152 506 365 7 8 2,585 618 365 171 3,394 982 267 149 0 0
Chapter 11—Interior River Lowland Ecoregion 121

Table 4. Principal land-cover conversions in Interior River Lowland Ecoregion, showing amount of area changed (and 

margin of error, calculated at 85-percent confidence level) for each conversion during each of four time periods and also 

during overall study period. See appendix 3 for definitions of land-cover classifications.

[Values given for “other” class are combined totals of values for other land-cover classes not listed in that time period. Abbreviations: n/a, not 

applicable]

Period From class To class

Area 

changed

Margin of 

error

Standard 

error Percent of 

ecoregion

Percent 

of all 

changes (km2) (+/− km2) (km2)

1973–1980 Forest Agriculture 856 377 257 0.9 50.0

Agriculture Developed 304 355 242 0.3 17.8

Forest Mechanically disturbed 59 57 39 0.1 3.5

Grassland/Shrubland Forest 58 68 47 0.1 3.4

Agriculture Forest 57 23 16 0.1 3.3

Other Other 378 n/a n/a 0.4 22.1

Totals 1,712 1.8 100.0

1980–1986 Forest Agriculture 603 221 150 0.6 47.2

Agriculture Developed 138 98 67 0.1 10.8

Wetland Agriculture 103 113 77 0.1 8.1

Grassland/Shrubland Forest 65 81 55 0.1 5.1

Agriculture Wetland 48 68 47 0.1 3.7

Other Other 320 n/a n/a 0.3 25.0

Totals 1,277 1.4 100.0

1986–1992 Forest Agriculture 409 174 118 0.4 37.4

Agriculture Developed 170 102 70 0.2 15.5

Agriculture Mining 143 151 103 0.2 13.1

Mining Agriculture 43 45 31 0.0 3.9

Forest Developed 42 32 22 0.0 3.9

Other Other 288 n/a n/a 0.3 26.3

Totals 1,095 1.2 100.0

1992–2000 Agriculture Developed 574 454 309 0.6 35.2

Forest Agriculture 245 94 64 0.3 15.0

Mining Agriculture 139 169 115 0.1 8.5

Forest Developed 120 106 72 0.1 7.3

Agriculture Forest 118 64 43 0.1 7.3

Other Other 435 n/a n/a 0.5 26.7

Totals 1,631 1.7 100.0

1973–2000

(overall)

Forest Agriculture 2,113 601 409 2.3 37.0

Agriculture Developed 1,186 890 606 1.3 20.8

Forest Developed 243 181 124 0.3 4.3

Agriculture Forest 236 84 57 0.3 4.1

Agriculture Mining 210 170 116 0.2 3.7

Other Other 1,727 n/a n/a 1.9 30.2

Totals 5,716 6.1 100.0
122 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

References Cited

Demographia, 2003, U.S. metropolitan area population—

1990–2000, Belleville, Illinois: Wendell Cox Consultancy 

Web site, accessed April 8, 2013, at http://www.demographia.

com/db-usmet2000.htm.

Milici, R.C., and Dennen, K.O., 2009, Production and depletion 

of Appalachian and Illinois basin coal resources, chap. H 

of Pierce, B.S., and Dennen, K.O., eds., The National Coal 

Resource Assessment overview: U.S. Geological Survey 

Professional Paper 1625–F, 18 p., available at http://pubs.

usgs.gov/pp/1625f/.

Omernik, J.M., 1987, Ecoregions of the conterminous United 

States: Annals of the Association of American Geographers, 

v. 77, no. 1, p. 118–125.

U.S. Environmental Protection Agency, 1999, Level 

III ecoregions of the continental United States: U.S. 

Environmental Protection Agency, National Health 

and Environmental Effects Research Laboratory, scale 

1:7,500,000, available at ftp://ftp.epa.gov/wed/ecoregions/

usgs/useco_March1999_v5.pdf.

Varanka, D.E., and Shaver, D.K., 2007, Land-use change trends 

in the Interior River Lowland Ecoregion: U.S. Geological 

Survey Scientific Investigations Report 2007–5145, 12 p., 

available at http://pubs.usgs.gov/sir/2007/5145/.

Vogelmann, J.E., Howard, S.M., Yang, L., Larson, C.R., 

Wylie, B.K., and van Driel, N., 2001, Completion of the 

1990s National Land Cover Data Set for the conterminous 

United States from Landsat Thematic Mapper data and 

ancillary data sources: Photogrammetric Engineering & 

Remote Sensing, v. 67, p. 650–662.

Wiken, E., Jiménez Nava, F., and Griffith, G., 2011, North 

American terrestrial ecoregions—Level III: Montreal, 

Canada, Commission for Environmental Cooperation, 

149 p., accessed October 31, 2013, at http://www.cec.org/

Storage/133/15860_QA07.30-32_NP_NA_Terrestrial_

Ecoregions_Level_3_Final-2june11.pdf.

Woods, A.J., Omernik, J.M., Brockman, C.S., Gerber, T.D., 

Hosteter, W.D., and Azevedo, S.H., 1998, Ecoregions of 

Indiana and Ohio: U.S. Geological Survey Ecoregion Map 

Series, scale 1:500,000, available at http://www.epa.gov/

wed/pages/ecoregions/ohin_eco.htm.

Woods, A.J., Omernik, J.M., Pederson, C.L., and Moran, 

B.C., 2006, Level III and IV ecoregions of Illinois: 

U.S. Environmental Protection Agency Report, 

EPA/600/R-06/104, 45 p., accessed October 28, 2013, 

at http://www.epa.gov/wed/pages/publications/authored/

EPA600R-0610%20Ecoregions%20of%20Illinois%20

Woods.pdf. 
South Central Highlands Ecoregions

Chapter 12

Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000 

Edited by Roger F. Auch and Krista A. Karstensen 

U.S. Geological Survey Professional Paper 1794–C, 2015

Ozark Highlands Ecoregion

By Krista A. Karstensen

Ecoregion Description 

The Ozark Highlands Ecoregion, which covers about 

108,332 km2 (41,827 mi2), includes parts of southern Missouri, 

northern Arkansas, and northeastern Oklahoma, as well as 

the extreme southeastern corner of Kansas (fig.1) (Omernik, 

1987; Wiken and others, 2011). Neighboring ecoregions are 

the Central Irregular Plains Ecoregion to the west and north, 

the Interior River Lowlands Ecoregion to the northeast, the 

Mississippi Alluvial Plain Ecoregion to the southeast, and the 

Central

Irregular

Plains

AV

Mississippi

Alluvial Plain

Boston

Mountains

Interior

River Lowland

CCBP

93° 92° 91° 90°

95° 94°

95°

39°

38°

37°

38°

39°

36°

0 50 100

0 50 100

MILES

KILOMETERS

Ecoregion boundary

Sample block (10 x 10 km)

Land-use/land-cover class

Water

Developed

Transitional

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Ice/Snow

EXPLANATION

OK

ARKANSAS

MISSOURI 

ILLINOIS

COLE

COUNTY

GREENE

COUNTY

TANEY COUNTY

KS

Fort

Leonard

Wood

Saint Robert

Saint

Louis

Waynesville

Harry S

Truman

Reservoir

Lake

of the

Ozarks

Meramec River

Black River

River

Francis

Saint 

Fayetteville

River

River

White

Illinois

Joplin Springfield

Bentonville

Columbia

Misso uri River

Mississip pi River

Lake Taneycomo Table Rock

Lake

Bull Shoals Lake

Gasconade River

Osage River

OZARK

PLATEAU

B O S T O N M O U N T A I N S

S A I N T F R A N C O I S

M O U N T A I N S

Jefferson City

Branson

KS

OK

MO

AR

Ozark Highlands

Ecoregion

Figure 1. Map of Ozark Highlands Ecoregion and surrounding ecoregions, showing land-use/land-cover classes from 1992 National Land 

Cover Dataset (Vogelmann and others, 2001); note that not all land-use/

land-cover classes shown in explanation may be depicted on map; 

note also that, for this “Status and Trends of Land Change” study, transitional land-cover class was subdivided into mechanically disturbed 

and nonmechanically disturbed classes. Squares indicate locations of 

10 x 10 km sample blocks analyzed in study. Index map shows locations 

of geographic features mentioned in text. Abbreviations for Midwest–

South Central United States ecoregions are listed in appendix 2. Also 

shown is part of one Great Plains ecoregion, Central Irregular Plains. 

See appendix 3 for definitions of land-use/land-cover classifications.
126 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Boston Mountains Ecoregion to the south (fig. 1). Elevations in 

the ecoregion range from 76 to 274 m, and local relief ranges 

from 15 to 244 m (Woods and others, 2004). Urban areas in 

the ecoregion include the cities of Bentonville and Fayetteville, 

Arkansas, and Jefferson City, Columbia, Springfield, Joplin, and 

Branson, Missouri. 

The ecoregion is part of the Ozark Plateaus physiographic 

province, which consists of a structural dome of sedimentary 

and igneous rocks (Davis and Bell, 1998). The sedimentary 

rocks generally dip away from the igneous core of the Saint 

Francois Mountains in southeastern Missouri to form the 

Salem-Springfield Plateaus (formerly known as the “Salem 

Plateau” and the “Springfield Plateau” [Fenneman, 1938]) 

section of the Ozark Plateaus physiographic province. The 

Salem-Springfield Plateaus are underlain by limestone and 

dolomite, which have formed the karst topography responsible 

for the ecoregion’s unique hydrologic features such as losing 

streams, springs, seeps, and fens (U.S. Forest Service, 2010). 

The soils that have formed in this geologic landscape have 

shaped both the natural vegetation and the agricultural 

character of the Ozark Highlands Ecoregion (L. Handley, U.S. 

Geological Survey, written commun., 2010).

The Ozark Highlands Ecoregion generally has a mesic 

temperature regime, with annual precipitation of about 1,070 

to 1,240 mm (42–49 in.) (Woods and others, 2004). The 

continental climate of the ecoregion is affected by prevailing 

easterly storm systems, as well as Gulf of Mexico moisture 

sources and occasional incursions of polar fronts (Jacobson 

and Primm, 1997). 

Several river systems drain the ecoregion; these include 

the Osage, Gasconade, Meramec, Saint Francis, Black, White, 

and Illinois Rivers. Most rivers drain either radially away 

from south-central Missouri or northward from the Boston 

Mountains (Petersen and others, 1998). The annual mean 

streamflow of individual streams within the ecoregion varies 

substantially from year to year. Minimum monthly streamflows 

generally occur in the summer and autumn (July to October), 

and maximum monthly streamflows typically occur in spring 

(March to May) (Adamski and others, 1995). 

The Ozark Highlands Ecoregion has some of the largest 

freshwater springs in North America, providing habitat for 

a wide variety of endemic species such as the Ozark shiner 

(Notropis ozarcanus) (The Nature Conservancy, 2003). 

Although the ecoregion has some small sinkhole ponds, it 

has few natural lakes (U.S. Forest Service, 2010). The 1941 

initiation of the Missouri Pond Program (Missouri Department 

of Conservation, 2012) had a noticeable effect on the 

ecoregion. Missouri farmers embraced the program as a way 

to provide water for their livestock, as well as for recreational 

and domestic uses, and sportsmen also were encouraged by its 

provision of fish- and waterfowl-habitat incentives (Missouri 

Department of Conservation, 2012). This conservation effort 

likely is responsible for creating many of the farm ponds 

across the ecoregion. The Ozark Highlands Ecoregion also has 

several substantial reservoirs along large rivers; these include 

Lake Taneycomo, Bull Shoals Lake, Table Rock Lake, Lake of 

Figure 2. Hay land and pastureland south of Jefferson City, in 

Cole County, Missouri.

the Ozarks, and Harry S Truman Reservoir. These large water 

bodies provide recreational boating and fishing activities and 

generally attract many tourists during the summer months. 

For example, most of the shoreline of Lake of the Ozarks, one 

of the largest manmade lakes in the Midwest–South Central 

United States, is privately owned and is occupied by vacation 

homes, hotels, condominiums, and restaurants. 

Land cover in the Ozark Highlands Ecoregion is 

characterized primarily by forest in the east and agriculture in the 

west (figs.1,2). The oak–hickory (Quercus spp. and Carya spp.) 

forest in the ecoregion provided a profitable environment for the 

timber boom of the late 1800s, which lasted until 1920. During 

this period, the ecoregion experienced cutover, and controlled 

forest burns were suppressed. Between 1960 and 1993, upland 

areas increasingly were used for grazing and row crops; valley 

slopes were used for woodland grazing and managed timber; and 

valley bottoms were cleared for pasture and row crops, with some 

reversion to forest (Jacobson and Primm, 1997). The agricultural 

crisis in the Midwest that occurred during the 1980s (Demissie, 

1986) had an adverse effect on the ecoregion. Throughout this 

period, the acreage harvested for crops, as well as the number 

of cattle sold, decreased substantially until recovery in the early 

1990s. Most farm income in the Ozark Highlands Ecoregion 

in the early 2000s was from the sale of cattle, poultry, or hogs 

(Woods and others, 2004).

In 2000, developed land accounted for an estimated 

2.1percent of the ecoregion, mostly around major urban areas. 

Springfield, Missouri, was the largest city in the ecoregion in 

2000 (population 151,580). The other urban areas (Jefferson 

City, Columbia, Joplin, Branson, Bentonville, and Fayetteville) 

had less than 100,000 residents each in 2000. The developed 

land in the Ozark Highlands Ecoregion had diverse sources 

of growth. For example, in Branson, Missouri, which had 

a resident population of only 6,050 people in 2000 (U.S. 

Census Bureau, 2001), local recreational and entertainment 

opportunities attract upwards of 7 million tourists annually 

(Lambe, 2008). The small cities of Saint Robert and 

Waynesville, Missouri, grew rapidly starting in 1960 following 

growth of the Fort Leonard Wood military installation. One 

sample block included in this ecoregion analysis is about 

1.5km from the military installation’s border (fig. 3); the 
Chapter 12—Ozark Highlands Ecoregion 127

92°16'30" 92°15'30" 92°14'30" 92°13'30" 92°12'30" 92°11'30" 92°10'30" 92°9'30" 92°8'30" 92°7'30" 92°6'30" 92°5'30"

37°51'0"

37°50'30"

37°50'0"

37°49'30"

37°49'0"

37°48'30"

37°48'0"

37°47'30"

37°47'0"

37°46'30"

37°46'0"

37°45'30"

37°45'0"

37°44'30"

37°44'0"

37°43'30"

37°43'0"

INDEX MAP OF SAMPLE BLOCKS

IN OZARK HIGHLANDS ECOREGION

Sample block

(10 × 10 km)

Base from The National Map, U.S. Geological Survey

North American Datum of 1983 (NAD 83)

UTM Zone 15, Universal Transverse Mercator projection

Waynesville

Fort Leonard Wood Fort Leonard Wood

Waynesville

Fort Leonard Wood

Waynesville

Fort Leonard Wood

Waynesville

0 0.5 1 2 MILES

0 1 2 0.5 KILOMETERS

Figure 3. Aerial photograph of area 

surrounding Waynesville, Missouri, showing 

its proximity to Fort Leonard Wood military 

installation. Red outline in aerial photograph 

shows area of sample block 304; red square 

in index map shows location of sample 

block 304 in Ozark Highlands Ecoregion.
128 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

0 12 24 36

Area, as percent of ecoregion

Ecoregion 

DA

HELP

CCBP

SMNIDP

NCHF

BM

IRL

SEWTP

OH

EDP

ECBP

NMW

AV

MAP

NLF

SCP

OM

EXPLANATION

Change in one time period

Change in two time periods

Change in three time periods

Change in four time periods

Change in four time periods

0.5

0.0

1.0

1.5

2.5

3.0

2.0

3.5

1973 to 1980 1980 to 1986 1986 to 1992 1992 to 2000

Average annual change, as percent of ecoregion

Time period

sample block includes Waynesville, which is one of the larger 

towns adjacent to the Fort Leonard Wood military installation. 

The addition of many military personnel at any one location 

may potentially affect the footprint (overall areal extent) of 

land-use and land-cover change, not only for the military 

installation itself but also for the surrounding community 

(Karstensen and Loveland, 2008).

Contemporary Land-Cover Change

(1973 to 2000)

The overall spatial change (the percentage of land area 

that changed at least one time) between 1973 and 2000 in the 

Ozark Highlands Ecoregion is estimated at 5.9 percent (table1).

Compared to the other Midwest–South Central United States 

ecoregions, change in the Ozark Highlands Ecoregion was 

moderate (fig.4): about 4.8 percent of the ecoregion changed

once during the study period, 1.1 percent changed twice, and 

0.1 percent changed three times (table1). The amount of change 

varied slightly between 1973 and 2000, with the total change 

per time period (as percent of the ecoregion) ranging from 1.5 

to 2.0percent (table 2). When normalized to account for uneven 

time periods, the average annual rate of change for the first 

three time periods (1973–1980, 1980–1986, and 1986–1992) 

was 0.3percent, and, for the fourth time period (1992–2000), it

was 0.2 percent (table 2; fig. 5). This decrease of overall change 

in the middle of the study period may be due to the agricultural 

crisis in the Midwest that occurred in the 1980s. 

The forest and agriculture land-cover classes experienced 

the highest amount of change during the study period 

(table3; fig. 6). Despite covering an estimated 60,893 km2

of the ecoregion in 2000, forest had a net loss of 3.9 percent 

(2,484 km2, 2.3 percent of the ecoregion area). Agriculture, 

which covered about 39,820 km2 in 2000, had a net gain of 

about 5 percent (1,881 km2, 1.7 percent of the ecoregion area). 

Grassland/shrubland and developed had the third and fourth 

highest amount of land in 2000, covering 2.8 percent and 

2.1percent of the ecoregion, respectively (table 3). 

Neighboring ecoregions also experienced an overall net 

decrease in forest (Karstensen, 2008, 2009a,b; Sayler, 2009); 

however, forest loss in the Ozark Highlands Ecoregion was 

due to agricultural expansion, whereas the driving forces of 

land-cover change in the other ecoregions may have been more 

complex. For example, in the Boston Mountains Ecoregion 

to the south, which had a total net forest loss of 1.7 percent of 

ecoregion area between 1973 and 2000, agricultural expansion 

also occurred (a net increase of 0.7 percent of ecoregion area). 

Forest loss in the Boston Mountains Ecoregion, however, 

more likely is attributable to forest-logging practices and, 

thus, is associated with the mechanically disturbed land-cover 

class (rather than agriculture). A neighboring ecoregion that 

also showed an increase in agricultural land (an increase of 

0.7percent of ecoregion area) from forested land was the 

Interior River Lowland Ecoregion to the northeast.

The three leading land-cover-class conversions between 

1973 and 2000 in the Ozark Highlands Ecoregion were (1) 

forest to agriculture, (2) agriculture to grassland/shrubland, 

and (3) grassland/shrubland to forest (table 4). Overall, 

the most common type of conversion in each time period 

was from forest to agriculture: between 1973 and 2000, an 

Figure 4. Overall spatial change in Ozark Highlands Ecoregion 

(OH; darker bars) compared with that of all 17 Midwest–South 

Central United States ecoregions (lighter bars). Each horizontal 

set of bars shows proportions of ecoregion that changed during 

one, two, three, or four time periods; highest level of spatial 

change in Ozark Highlands Ecoregion (four time periods) labeled 

for clarity. See table 2 for years covered by each time period. See 

appendix 2 for key to ecoregion abbreviations.

Figure 5. Estimates of land-cover change per time period,

normalized to annual rates of change for all 17 Midwest–South Central 

United States ecoregions (gray bars). Estimates of change for Ozark 

Highlands Ecoregion are represented by red bars in each time period.
Chapter 12—Ozark Highlands Ecoregion 129

estimated 2,593 km2 were converted from forest to agriculture. 

This conversion may have resulted in a larger net increase 

in agriculture if agricultural land had not been reverting to 

grassland/shrubland at the same time (table 4). This may have 

been the result of the Conservation Reserve Program (CRP), 

which offered financial incentives for farmers to retire marginal 

agricultural land and convert it to native grasses or trees, 

usually for ten years’ duration (Johnson and Maxwell, 2001).

Changes in forest practices were one of the drivers of land 

change in the ecoregion. Most large-scale timber operations in 

the Ozark Highlands Ecoregion began in the late 1800s with 

the construction of railroads. At the end of this timber-boom 

period (1920), most of the marketable shortleaf pine (Pinus 

echinata) was depleted, thereby shifting production to smaller 

companies that made railroad ties, stave bolts, firewood, and 

charcoal (Cunningham and Hauser, 1989; Stevens, 1991; 

Jacobson and Primm, 1997). Increases in timber production 

from the mid-1950s to the early 1970s represented renewed 

cutting of second-growth forests (Cunningham and Hauser, 

1989; Jacobson and Primm, 1997). This study has shown that 

the period between 1973 and 1980 had the greatest amount of 

forested land when compared to the other three time periods, 

−1

−0.5

0

0.5

1

1973–1980 1980–1986 

Time period

1986–1992 1992–2000 

Area changed, as percent of ecoregion 

Water

Developed

Mechanically disturbed

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Nonmechanically disturbed

Ice/Snow

EXPLANATION

LAND-USE/LAND-COVER CLASS

0

50

100

150

200

250

300

350

Farmland enrolled (under contract) in Conservation

1986 1988 1990 1992 1994 1996 1998 2000

Reserve Program, in thousands of acres

Year

0

50,000

100,000

200,000

250,000

150,000

300,000

1900 1910 1920 1930

Population

Census year

1940 1950 1960 1970 1980 1990 2000

Greene County

Taney County

Figure 8. Population growth in Greene and Taney Counties, 

Missouri, during 20th century (U.S. Census Bureau, 1994, 2000). 

Growth of these counties is due primarily to increasing populations 

of Springfield and Branson, Missouri. 

Figure 6. Normalized average net change in Ozark Highlands 

Ecoregion by time period for each land-cover class. Bars above 

zero axis represent net gain, whereas bars below zero represent 

net loss. Note that not all land-cover classes shown in explanation 

may be represented in figure. See appendix 3 for definitions of 

land-use and land-cover classifications.

Figure 7. Cumulative enrollment (acres under contract) in 

Conservation Reserve Program between 1986 and 2000 in counties 

within Ozark Highlands Ecoregion (U.S. Department of Agriculture, 

2010). Enrollments initially increased before declining in late 1990s. 

which may be indicative of the second-growth forests that 

were allowed to reach maturity before periods of increased 

agricultural expansion and less frequent burning.

In the late 1960s and early 1970s, net farm income in the 

Ozark Highlands Ecoregion increased significantly owing to 

both an increase in domestic prices and the growth in export 

markets (Demissie, 1986). This trend was common in the 

Midwest–South Central United States region, and overall 

agricultural expansion occurred in the region primarily because 

of the availability of abundant credit from various sources, 

as well as high rates of inflation and low real-estate interest 

rates. In particular, net farm income in Missouri doubled 
130 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

between 1964 and 1974 (Demissie, 1986), a trend that may be 

recorded in this study’s statistics as the conversion, between 

1973 and 1980, of the greatest amount of area from forest to 

agriculture, which likely is due to the clearing of forested land 

for primarily cattle- and poultry-based agricultural expansion. 

Agro-economic markets are subject to change, and, 

during the study period, many farmers assumed heavy debt 

loads, becoming financially vulnerable to sudden shifts in 

economic forces (Stam and Dixon, 2004). In the early 1980s, 

economic conditions reversed as total farm debt increased, 

land values became inflated, and export markets contracted. 

In addition, substantial problems with farm lenders arose. The 

farm economic crisis is important to note primarily because, 

in the early 1980s, agriculture was still a predominant landcover class in the ecoregion despite decreased agricultural 

production. Moreover, an increase in the amount of 

agricultural land that was abandoned may have taken place in 

the ecoregion during the two time periods (1980–1986, 1986–

1992) in which the farm economic crisis occurred. Although 

CRP enrollment in the Ozark Highlands Ecoregion decreased 

in the later 1990s, the program may have contributed to 

the patterns of land-cover change across the ecoregion 

(fig.7). Conversions from agriculture to grassland/shrubland 

recorded in this study indicate agricultural abandonment, 

deintensification, or enrollment of agricultural land in the CRP. 

During the third and fourth time periods (1986–1992, 1992–

2000), farmers likely either placed marginal agricultural land 

under CRP contracts or maintained less intensive management 

practices for various reasons, including economic ones.

The predominant land-cover change in the Ozark 

Highlands Ecoregion is attributable to the cutting of forests for 

agricultural expansion, as is shown in this study’s statistics: in 

each of the four time periods, forest decreased and agriculture 

increased. Despite the economic hardships that affected farms 

in the 1980s, agricultural land increased during the study 

period. Cattle, poultry, and hogs continued to be the primary 

livestock produced and sold, and corn continued to be the 

primary agricultural crop throughout the ecoregion. Although 

changes in developed land were locally substantial during the 

study period (as exemplified by population growth around 

metropolitan Springfield and Branson [fig. 8]), the ecoregion 

as a whole showed little net change in developed land (table 3) 

because the number of urban areas in the ecoregion was limited. 

In evaluating future land-cover change in the Ozark 

Highlands Ecoregion, the tradeoffs between agricultural and 

forest land uses should be considered, as well as the rapid 

growth of the larger cities in the ecoregion. The growing 

population will place greater demands on resources, which will, 

in turn, result in future demands on land cover and land use 

throughout the ecoregion.

Table 1. Percentage of Ozark Highlands Ecoregion land cover 

that changed at least one time during study period (1973–2000) and 

associated statistical error.

[Most sample pixels remained unchanged (94.1 percent), whereas 5.9 percent 

changed at least once throughout study period] 

Number

of

changes

Percent

of

ecoregion

Margin

of error

(+/− %)

Lower

bound

(%)

Upper

bound

(%)

Standard

error

(%)

Relative

error

(%)

1 4.8 0.5 4.2 5.2 0.3 7.3

2 1.1 0.3 0.8 1.3 0.2 16.5

3 0.1 0.0 0.1 0.1 0.0 29.6

4 0.0 0.0 0.0 0.0 0.0 57.7

Overall 

spatial 

change

5.9 0.7 5.3 6.6 0.4 7.5
Chapter 12—Ozark Highlands Ecoregion 131

Table 3. Estimated area (and margin of error) of each land-cover class in Ozark HIghlands Ecoregion, calculated five times between 

1973 and 2000. See appendix 3 for definitions of land-cover classifications.

Water Developed

Mechanically 

disturbed

Mining Barren Forest Grassland/

Shrubland Agriculture Wetland

Nonmechanically 

disturbed

% +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/−

Area, in percent stratum

1973 1.2 0.6 1.7 0.8 0.1 0.1 0.1 0.1 0.1 0.1 58.5 4.2 3.0 0.9 35.0 4.2 0.3 0.1 0.0 0.0

1980 1.2 0.6 1.8 0.9 0.2 0.1 0.1 0.1 0.1 0.1 57.7 4.1 2.8 0.8 35.7 4.2 0.3 0.1 0.0 0.0

1986 1.2 0.6 1.9 0.9 0.1 0.1 0.1 0.1 0.1 0.1 57.4 4.1 2.6 0.8 36.2 4.2 0.3 0.1 0.0 0.0

1992 1.3 0.6 2.0 0.9 0.1 0.1 0.1 0.1 0.1 0.1 56.9 4.1 2.7 0.8 36.5 4.2 0.3 0.1 0.0 0.0

2000 1.3 0.6 2.1 1.0 0.3 0.1 0.1 0.1 0.1 0.1 56.2 4.0 2.8 0.8 36.8 4.2 0.3 0.1 0.0 0.0

Net

change 0.1 0.0 0.4 0.2 0.2 0.2 0.0 0.0 0.0 0.0 –2.3 0.4 –0.2 0.3 1.7 0.5 0.0 0.0 0.0 0.0

Gross

change 0.1 0.0 0.4 0.2 0.8 0.2 0.0 0.0 0.1 0.0 3.1 0.4 1.6 0.3 3.0 0.3 0.0 0.0 0.0 0.0

Area, in square kilometers

1973 1,292 617 1,789 849 115 108 74 83 141 99 63,377 4,515 3,247 925 37,939 4,581 358 130 0 0

1980 1,309 613 1,957 950 178 64 63 82 148 95 62,541 4,426 3,081 918 38,698 4,550 357 130 0 0

1986 1,342 616 2,034 971 154 62 65 82 137 89 62,192 4,430 2,828 857 39,226 4,579 356 128 0 0

1992 1,365 618 2,160 1,020 162 69 66 82 134 87 61,684 4,430 2,876 834 39,529 4,590 356 128 0 0

2000 1,387 619 2,273 1,073 346 154 67 82 136 86 60,893 4,336 3,060 890 39,820 4,566 352 127 0 0

Net

change 94 38 484 244 230 188 –7 17 –6 25 –2,484 471 –188 361 1,881 543 –6 12 0 0

Gross

change 161 54 484 244 827 223 17 17 63 40 3,311 420 1,776 369 3,258 376 52 30 0 0

Table 2. Raw estimates of change in Ozark Highlands Ecoregion land cover, computed for each of four 

time periods between 1973 and 2000, and associated error at 85-percent confidence level.

[Estimates of change per period normalized to annual rate of change for each time period]

Period Total change

(% of ecoregion)

Margin of 

error

(+/− %)

Lower 

bound

(%)

Upper bound

(%)

Standard 

error

(%)

Relative 

error

(%)

Average rate

(% per year)

Estimate of change, in percent stratum

1973–1980 2.0 0.4 1.7 2.4 0.2 11.9 0.3

1980–1986 1.5 0.2 1.3 1.8 0.2 10.0 0.3

1986–1992 1.8 0.3 1.5 2.1 0.2 11.0 0.3

1992–2000 1.8 0.3 1.6 2.1 0.2 9.5 0.2

Estimate of change, in square kilometers

1973–1980 2,201 386 1,816 2,587 263 11.9 314

1980–1986 1,665 245 1,420 1,910 167 10.0 277

1986–1992 1,955 315 1,640 2,271 215 11.0 326

1992–2000 2,003 278 1,725 2,281 189 9.5 250
132 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Table 4. Principal land-cover conversions in Ozark Highlands Ecoregion, showing amount of area changed (and margin of error, 

calculated at 85-percent confidence level) for each conversion during each of four time periods and also during overall study 

period. See appendix 3 for definitions of land-cover classifications.

[Values given for “other” class are combined totals of values for other land-cover classes not listed in that time period. Abbreviations: n/a, not applicable]

Period From class To class

Area 

changed

Margin of 

error

Standard 

error Percent of 

ecoregion

Percent of all 

changes (km2) (+/− km2) (km2)

1973–1980 Forest Agriculture 905 189 129 0.8 41.1

Grassland/Shrubland Forest 321 158 108 0.3 14.6

Agriculture Grassland/Shrubland 241 75 51 0.2 10.9

Forest Mechanically disturbed 177 64 43 0.2 8.1

Grassland/Shrubland Agriculture 158 100 68 0.1 7.2

Other Other 399 n/a n/a 0.4 18.1

Totals 2,201 2.0 100.0

1980–1986 Forest Agriculture 477 117 80 0.4 28.7

Grassland/Shrubland Forest 307 115 79 0.3 18.4

Grassland/Shrubland Agriculture 193 111 76 0.2 11.6

Agriculture Grassland/Shrubland 166 79 54 0.2 10.0

Forest Mechanically disturbed 153 62 42 0.1 9.2

Other Other 369 n/a n/a 0.3 22.2

Totals 1,665 1.5 100.0

1986–1992 Forest Agriculture 581 134 92 0.5 29.7

Agriculture Grassland/Shrubland 367 125 85 0.3 18.8

Grassland/Shrubland Agriculture 222 120 82 0.2 11.4

Grassland/Shrubland Forest 176 78 53 0.2 9.0

Forest Mechanically disturbed 157 69 47 0.1 8.0

Other Other 452 n/a n/a 0.4 23.1

Totals 1,955 1.8 100.0

1992–2000 Forest Agriculture 630 130 89 0.6 31.5

Agriculture Grassland/Shrubland 375 119 81 0.3 18.7

Forest Mechanically disturbed 344 154 105 0.3 17.2

Grassland/Shrubland Forest 184 69 47 0.2 9.2

Grassland/Shrubland Agriculture 105 43 29 0.1 5.2

Other Other 365 n/a n/a 0.3 18.2

Totals 2,003 1.8 100.0

1973–2000

(overall)

Forest Agriculture 2,593 392 267 2.4 33.1

Agriculture Grassland/Shrubland 1,148 295 201 1.1 14.7

Grassland/Shrubland Forest 987 295 201 0.9 12.6

Forest Mechanically disturbed 831 263 180 0.8 10.6

Grassland/Shrubland Agriculture 679 324 221 0.6 8.7

Other Other 1,586 n/a n/a 1.5 20.3

Totals 7,824 7.2 100.0
Chapter 12—Ozark Highlands Ecoregion 133

References Cited

Adamski, J.C., Petersen, J.C., Freiwald, D.A., and Davis, 

J.V., 1995, Environmental and hydrologic setting of the 

Ozark Plateaus study unit, Arkansas, Kansas, Missouri, 

and Oklahoma: U.S. Geological Survey Water-Resources 

Investigations Report 94–4022, 69 p., available at http://

pubs.usgs.gov/wri/wri944022/.

Cunningham, R.J., and Hauser, C., 1989, The decline of the 

Missouri Ozark forest between 1820 and 1920, in Waldrop, 

T.A., ed., Proceedings of the conference on pine-hardwood 

mixtures, Atlanta, Georgia, April 18–19, 1989: U.S. Forest 

Service, Southeastern Forest Experiment Station, p. 34–37. 

Davis, J.V., and Bell, R.W., 1998, Water-quality assessment of 

the Ozark Plateaus study unit, Arkansas, Kansas, Missouri, 

and Oklahoma—Nutrients, bacteria, organic carbon, 

and suspended sediment in surface water, 1993-95: U.S. 

Geological Survey Water-Resources Investigations Report 

98–4164, 56 p., available at http://pubs.usgs.gov/wri/wri98-

4164/.

Demissie, E., 1986, Farm financial trend in Missouri and its 

future implications: Agriculture and Human Values, v. 3, no. 

4, p. 66–74.

Fenneman, N.M., 1938, Physiography of the eastern United 

States: New York, McGraw-Hill, 714 p. 

Jacobson, R.B., and Primm, A.T., 1997, Historical land-use 

changes and potential effects on stream disturbance in the 

Ozark Plateaus, Missouri: U.S. Geological Survey Water 

Supply Paper 2484, 85 p., available at http://pubs.er.usgs.

gov/publication/wsp2484.

Johnson, J., and Maxwell, B., 2001, The role of the Conservation 

Reserve Program in controlling rural residential development: 

Journal of Rural Studies, v. 17, p. 323–332.

Karstensen, K.A., 2008, Interior River Lowland Ecoregion 

summary report: U.S. Geological Survey Open-File 

Report 2008–1088, 5 p., available at http://pubs.usgs.gov/

of/2008/1088/.

Karstensen, K.A., 2009a, Land cover change in the Boston 

Mountains, 1973–2000: U.S. Geological Survey Open-File 

Report 2009–1281, 10 p., available at http://pubs.usgs.gov/

of/2009/1281/.

Karstensen, K.A., 2009b, Land-cover change in the Central 

Irregular Plains, 1973–2000: U.S. Geological Survey OpenFile Report 2009–1159, 8 p., available at http://pubs.usgs.

gov/of/2009/1159/.

Karstensen, K.A., and Loveland, T.R., 2008, Monitoring land 

use on military installations: The Military Engineer, v. 101, 

no. 657, p. 47–48.

Lambe, W., 2008, Small towns, big ideas—Case studies in 

small town community economic development: Chapel Hill, 

University of North Carolina School of Government, p. 243. 

Missouri Department of Conservation, 2012, The Missouri 

pond program: Missouri Department of Conservation 

Website, accessed February 25, 2013, at http://mdc.mo.gov/

conmag/2012/09/missouri-pond-program.

Omernik, J.M., 1987, Ecoregions of the conterminous United 

States: Annals of the Association of American Geographers, 

v. 77, no. 1, p. 118–125.

Petersen, J.C., Adamski, J.C., Bell, R.W., Davis, J.V., Femmer, 

S.R., Freiwald, D.A., and Joseph, R.L., 1998, Water quality 

in the Ozark Plateaus, Arkansas, Kansas, Missouri, and 

Oklahoma, 1992-95: U.S. Geological Survey Circular 1158, 

33 p., available at http://pubs.usgs.gov/circ/circ1158/. 

Sayler, K.L., 2009, Contemporary land-cover change in the 

Mississippi Alluvial Plain Ecoregion: U.S. Geological 

Survey, Lands Cover Trends Project Web site, accessed 

February 14, 2013, at http://landcovertrends.usgs.gov/mw/

eco73Report.html.

Stam, J.M., and Dixon, B.L., 2004, Farmer bankruptcies and 

farm exits in the United States, 1899–2002: U.S. Department 

of Agriculture, Economic Research Service, Agriculture 

Bulletin Number 788, 42 p., accessed February 14, 2013, at 

http://www.ers.usda.gov/publications/aib788/aib788.pdf.

Stevens, D.L., 1991, A homeland and hinterland—The Current 

and Jacks Fork Riverways: National Park Service, Midwest 

Regional Office, 248 p. 

The Nature Conservancy, 2003, Ozarks ecoregional 

conservation assessment: The Nature Conservancy, Ozarks 

Ecoregional Assessment Team, Midwestern Resource Office, 

248 p., available at http://www.nature.org/ourinitiatives/

regions/northamerica/unitedstates/oklahoma/explore/

ozarks-1.pdf.

U.S. Census Bureau, 1994, Population of counties by decennial 

census—1900 to 1990: U.S. Census Bureau database, 

accessed February 14, 2013, at http://www.census.gov/

population/cencounts/1900-90.txt.

U.S. Census Bureau, 2000, State and county quick facts—

Missouri: U.S. Census Bureau database, accessed February 

14, 2013, at http://quickfacts.census.gov/qfd/index.html.

U.S. Census Bureau, 2001, Geographic area—Branson city, 

Missouri, in Profiles of general demographic characteristics, 

2000—2000 Census of Population and Housing – Missouri: 

U.S. Census Bureau database, p. 546, accessed December 2, 

2013, at http://www.census.gov/prod/cen2000/dp1/2kh29.pdf.
134 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

U.S. Department of Agriculture, 2010, Conservation Reserve 

Program—Cumulative enrollment by year: U.S. Department 

of Agriculture, Farm Service Agency database, accessed 

February 14, 2013, at http://www.fsa.usda.gov/Internet/

FSA_File/cumulative08.xls.

U.S. Forest Service, 2010, Section 222A—Ozark Highlands, 

in Eastern broadleaf forest (continental), chap. 17 of

Ecological subregions of the United States: U.S. Forest 

Service, accessed February 14, 2013, at http://www.fs.fed.

us/land/pubs/ecoregions/ch17.html#222A.

Vogelmann, J.E., Howard, S.M., Yang, L., Larson, C.R., 

Wylie, B.K., and van Driel, N., 2001, Completion of the 

1990s National Land Cover Data Set for the conterminous 

United States from Landsat Thematic Mapper data and 

ancillary data sources: Photogrammetric Engineering & 

Remote Sensing, v. 67, p. 650–662.

Wiken, E., Jiménez Nava, F., and Griffith, G., 2011, North 

American terrestrial ecoregions–Level III: Montreal, 

Canada, Commission for Environmental Cooperation, 149 

p., accessed February 14, 2013, at http://www.cec.org/

Storage/133/15860_QA07.30-32_NP_NA_Terrestrial_

Ecoregions_Level_3_Final-2june11.pdf.

Woods, A.J., Foti, T.L., Chapman, S.S., Omernik, J.M., Wise, 

J.A., Murray, E.O., Prior, W.L., Pagan, J.B., Jr., Comstock, 

J.A., and Radford, M., 2004, Ecoregions of Arkansas: U.S. 

Geological Survey Ecoregion Map Series scale 1:1,000,000, 

available at http://www.epa.gov/wed/pages/ecoregions/

ar_eco.htm.
Chapter 13

Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000 

Edited by Roger F. Auch and Krista A. Karstensen 

U.S. Geological Survey Professional Paper 1794–C, 2015

Boston Mountains Ecoregion

By Krista A. Karstensen

Ecoregion Description 

The Boston Mountains Ecoregion encompasses about 

17,068 km2 (6,590 mi2) of rugged, mountainous terrain across 

northwestern Arkansas and northeastern Oklahoma (fig.1) 

(Omernik, 1987; Wiken and others, 2011). The ecoregion is 

bounded on the north by the Ozark Highlands Ecoregion, on 

the west by the Central Irregular Plains Ecoregion, and on the 

south by the Arkansas Valley Ecoregion; in addition, a small 

part of the Mississippi Alluvial Plain Ecoregion adjoins the 

far-eastern part of the ecoregion. 

Overall, the population density in the Boston Mountains 

Ecoregion is low; for example, one of the larger cities in 

the ecoregion—Tahlequah, Oklahoma—had population of 

14,458 in 2000 (U.S. Census Bureau, 2001). In Arkansas, 

the principal streams and rivers in the ecoregion include 

the Mulberry River and Big Piney Creek, which drain the 

94° 92°

36°

34°

KS

OK

MO

AR

Boston Mountains

Ecoregion

Ozark

Highlands

South Central Plains

Arkansas

Valley

Ouachita

Moutains

Mississippi

Alluvial Plain

Central

Irregular

Plains

0 5025 75 MILES

0 5025 75 KILOMETERS

Ecoregion boundary

Sample block (10 x 10 km)

Land-use/land-cover class

Water

Developed

Transitional

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Ice/Snow

EXPLANATION

B O S T O N M O U N T A I N S

Tahlequah Fayetteville

Fort Smith

White River

Tenkiller

Ferry Lake

Ozarks Plateau

Aquifer

ADAIR

COUNTY

Buff alo River

OKLAHOMA ARKANSAS

MISSOURI

K ni gs River

 Big Piney Creek

OZARK

NF

BUFFALO NATIONAL

RIVER

OZARK NATIONAL FOREST

LittleRed

A R.

rkansas

Arkansas

River

River

White River

B O S T O N M O U N T A I N S

O Z A R K P L A T E A U Mulberry River

NEWTON

COUNTY

Figure 1. Map of Boston 

Mountains Ecoregion and 

surrounding ecoregions, showing 

land-use/land-cover classes from 

1992 National Land Cover Dataset 

(Vogelmann and others, 2001); note 

that not all land-use/land-cover 

classes shown in explanation may 

be depicted on map; note also 

that, for this “Status and Trends of 

Land Change” study, transitional 

land-cover class was subdivided 

into mechanically disturbed and 

nonmechanically disturbed classes. 

Squares indicate locations of 10 

x 10 km sample blocks analyzed 

in study. Index map shows 

locations of geographic features 

mentioned in text. Abbreviations 

for Midwest–South Central United 

States ecoregions are listed in 

appendix 2. Also shown is part of 

one Great Plains ecoregion, Central 

Irregular Plains. See appendix 3 for 

definitions of land-use/land-cover 

classifications.

ecoregion to the south; the Buffalo and Little Red Rivers, 

which drain the ecoregion to the east; and the White and Kings 

Rivers, which drain the ecoregion to the north. In Oklahoma, 

the most important hydrologic features in the ecoregion are 

Tenkiller Ferry Lake and a small reach of the Arkansas River. 

The climate of the Boston Mountains Ecoregion generally 

is humid. Mean annual precipitation is about 1,270 mm (50in.),

and it is, in general, greater in the north than in the south 

(Woods and others, 2004). Maximum precipitation occurs in 

spring and autumn, whereas minimum precipitation occurs in 

midsummer. In the summer, many small streams commonly 

have little or no flow. Parts of the ecoregion are associated 

with the carbonate-rock aquifers of the Ozark Plateaus aquifer 

system (Reilly and others, 2008), and water quality in the 

Boston Mountains Ecoregion generally has been exceptional; 
136 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

however, nutrient concentrations generated in agricultural 

areas potentially present concerns for the health of freshwater 

ecosystems (Woods and others, 2004). In addition to forestry 

and agriculture, the Buffalo National River and parts of the 

Ozark National Forest help promote the recreational use of 

streams, lakes, rivers, and forests in the ecoregion.

The mountains in the Boston Mountains Ecoregion are 

remnants of the old, deeply dissected Ozark Plateau that 

has been eroded to produce steep-sided valleys separated 

by high flats and ridges (National Park Service, 2013). The 

most recent uplift of the Ozark Plateau, which includes the 

Boston Mountains, occurred about 300 million years ago, 

and weathering and erosion have been shaping the landscape 

since that time (Guccione, 2008). Elevations in the Boston 

Mountains Ecoregion range from about 60 m on valley floors 

to about 850 m on broad mountaintops, the northern part 

of the ecoregion typically being higher than the southern 

part (Woods and others, 2004); local relief in the Boston 

Mountains ranges from 46 to 274 m (Woods and others, 2004). 

The Boston Mountains are part of the greater Ozark Plateaus 

physiographic province, which has the greatest relief of any 

landform between the Appalachian Mountains to the east and 

the Rocky Mountains to the west (Guccione, 2008).

The Boston Mountains Ecoregion generally is underlain 

by gently folded sandstone, shale, cherty dolomite, and 

limestone. Soils on the upland areas primarily are Ultisols, and 

soils on terraces and floodplains primarily are Entisols (Woods 

and others, 2004). In the Boston Mountains Ecoregion, natural 

vegetation is composed mostly of oak–hickory (Quercus spp. 

and Carya spp.) forests that are fundamental to the timber 

industry, which plays an important role in the socioeconomic 

condition of the ecoregion. Species within hardwood forests 

on upland areas include northern red oak (Quercus rubra), 

blackjack oak (Quercus marilandica), post oak (Quercus 

stellata), white oak (Quercus alba), chinkapin oak (Quercus 

muehlenbergii), black hickory (Carya texana), mockernut 

hickory (Carya tomentosa), sugar maple (Acer saccharum), 

birch (Betula spp.), and cottonwood (Populus deltoides) 

(Woods and others, 2004; U.S. Department of Agriculture, 

2006). Species commonly found on the narrow floodplains and 

low terraces are southern red oak (Quercus falcata), sweetgum 

(Liquidambar styraciflua), willows (Salix spp.), and American 

sycamore (Platanus occidentalis) (Woods and others, 2004). 

Softwood species in the ecoregion include loblolly pine (Pinus 

taeda) and shortleaf pine (Pinus echinata). 

Land use in the Boston Mountains Ecoregion is 

associated principally with the forestry and timber industry. 

Although the generally infertile soils of the ecoregion preclude 

widespread agricultural land use, areas of low relief are used 

primarily for pasturelands, hay lands, and livestock farming 

such as the production of poultry and cattle (Petersen and 

others, 1998). In this study, conversions from mechanically 

disturbed to agriculture are associated with the clearing of 

forested land to create or expand pasturelands or to locate 

confined animal-feeding operations that are used mostly for 

poultry production.

Contemporary Land-Cover Change 

(1973 to 2000) 

The overall spatial change (the percentage of land area 

that changed at least one time) in the Boston Mountains 

Ecoregion between 1973 and 2000 is estimated at 5.5 

percent (table 1). Compared to other Midwest–South Central 

ecoregions, change in the Boston Mountains Ecoregion 

was relatively low (fig. 2): an estimated 2.7 percent of the 

ecoregion changed once during the study period, and 2.3 

percent changed twice (table 1). The amount of change varied 

somewhat between 1973 and 2000, with the total change per 

time period (as percent of the ecoregion) ranging from 2.0 to 

2.7 percent (table 2). The average annual rate of change was 

highest between 1980 and 1986 (0.4 percent) (table 2; fig. 3). 

The forest and mechanically disturbed land-cover classes 

changed the most during the 27-year study period (1973–

2000) (table 3). Forest had an estimated net loss of 2.2 percent 

from its 1973 base, a loss of 1.7 percent of the ecoregion 

area (table 3). This equates to an estimated decrease of 288 

km2 of forested land (table 3). Mechanically disturbed had an 

estimated net gain of 1.0 percent of the ecoregion area or 175 

km2, but this represents a more than 300 percent change from 

its very low 1973 estimated base (table 3). Forest loss in the 

ecoregion can be attributed to logging practices (mechanically 

disturbed land-cover class), as well as some conversion of 

forest to agriculture (tables 3,4; fig. 4). 

In the decade before 1973, the volume of growing 

stock (that is, living trees of a commercial species that have 

the potential to produce saw logs) in the Boston Mountains 

Ecoregion increased for softwood (for example, loblolly 

pine and shortleaf pine) at a much faster rate than that for 

hardwoods (Van Sickle, 1970). The gross annual growth for 

most forests in the Boston Mountains Ecoregion was about 40 

percent of the estimated potential (Van Sickle, 1970). Although 

overall forest productivity was low, mountain slopes and 

benches in the ecoregion had good hardwood-growing potential 

(Van Sickle, 1970). Because markets in the ecoregion were 

poorly developed, improvement cuts—made to improve the 

form or quality of remaining forest stands—were unprofitable. 

In 1970, long-range forestry programs were enacted, along with 

efforts to develop recreational opportunities, to supplement 

economic productivity (Van Sickle, 1970). 

One of the programs that may have affected the ecoregion 

is the Forestry Incentives Program (FIP). The FIP originally was 

authorized in 1978 to share as much as 65 percent of the costs of 

tree planting, timber-stand improvements, and related practices 

on nonindustrial, privately held forest lands (U.S. Forest 

Service, 1995). The FIP was intended to ensure the Nation’s 

ability to meet demands for timber products and to put more 

forest under a quality-management program. The availability 

of the program in designated counties was based on a U.S. 

Forest Service survey of total eligible private timber acreage 

that was potentially suitable for production of timber products 

(U.S. Forest Service, 1995). Although it may not necessarily 
Chapter 13—Boston Mountains Ecoregion 137

Figure 2. Overall spatial change in Boston Mountains Ecoregion 

(BM; darker bars) compared with that of all 17 Midwest–South 

Central United States ecoregions (lighter bars). Each horizontal 

set of bars shows proportions of ecoregion that changed during 

one, two, three, or four time periods; highest level of spatial 

change in Boston Mountains Ecoregion (four time periods) labeled 

for clarity. See table 2 for years covered by each time period. See 

appendix 2 for key to ecoregion abbreviations.

Figure 3. Estimates of land-cover change per time period,

normalized to annual rates of change for all 17 Midwest–South Central 

United States ecoregions (gray bars). Estimates of change for Boston 

Mountains Ecoregion are represented by red bars in each time period.

Figure 4. Normalized average net change in Boston Mountains 

Ecoregion by time period for each land-cover class. Bars above 

zero axis represent net gain, whereas bars below zero represent 

net loss. Note that not all land-cover classes shown in explanation 

may be represented in figure. See appendix 3 for definitions of 

land-use and land-cover classifications.

0 12 24 36

Area, as percent of ecoregion

Ecoregion 

DA

HELP

CCBP

SMNIDP

NCHF

BM

IRL

SEWTP

OH

EDP

ECBP

NMW

AV

MAP

NLF

SCP

OM

EXPLANATION

Change in one time period

Change in two time periods

Change in three time periods

Change in four time periods

Change in four time periods

0.5

0.0

1.0

1.5

2.5

3.0

2.0

3.5

1973 to 1980 1980 to 1986 1986 to 1992 1992 to 2000

Average annual change, as percent of ecoregion

Time period

−1

−0.5

0

0.5

1

1973–1980 1980–1986 

Time period

1986–1992 1992–2000 

Area changed, as percent of ecoregion 

Water

Developed

Mechanically disturbed

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Nonmechanically disturbed

Ice/Snow

EXPLANATION

LAND-USE/LAND-COVER CLASS

have been the benchmark for shaping land-cover change in the 

Boston Mountains Ecoregion, the FIP may at least have helped 

encourage tree growth and implement better management 

practices on private lands in the latter part of the study period 

(David Mason, U.S. Forest Service, written commun., 2009). 

In a 1999 assessment, primary mills—those that process 

roundwood in log or bolt form or as chipped roundwood—

were canvassed to document changes in wood-product output 

and wood-residue use (Bentley and others, 2002). This 

assessment complemented the Forest Inventory and Analysis 

(FIA) Program’s periodic inventory of volume and removals 

from timberland in Arkansas. In 1999, the roundwoodsoftwood output for all industrial products within census 

land area in the ecoregion ranged from less than 5 cubic 

feet per acre in the north and west to 5 to 20 cubic feet per 

acre in the south and east (Bentley and others, 2002). In the 

same year, the intensity of roundwood-hardwood output for 

all manufactured wood products in the ecoregion generally 

was less than that of softwoods, with most counties in the 

ecoregion producing less than 5 cubic feet per acre. The 

overall primary roundwood product for the ecoregion in 1999 

was saw logs (Bentley and others, 2002). 

The land-cover statistics show typical land-cover 

conversions affecting the ecoregion that are associated with the 

timber industry (for example, forest to mechanically disturbed, 

followed by mechanically disturbed to grassland/shrubland, 
138 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Figure 5. Clearcutting of forest, Adair County, Oklahoma.

Figure 6. Forest thinning, Newton County, Arkansas.

and ultimately reverting back to forest). In addition, changes 

in forest structure have occurred; for example, Heitzman and 

others (2007) noted that the forest structure in the Boston 

Mountains recently (1998–2000) has been affected by regional 

drought, as well as by the red oak borer (Enaphalodes 

rufulus), an insect that permanently damages the wood of 

living oak trees and causes a decrease in lumber grade (Donley 

and Acciavatti, 1997). Despite these adverse effects, forest 

remained the leading land-cover class in all time periods. 

Both privately held and publicly held forests are in the 

ecoregion, and both clearcutting (fig. 5) and thinning (fig. 6) 

are common timber-management practices. The amount of 

timberland in the ecoregion increased between the 1988 and 1995 

FIA surveys, with most of the timberland being held in private 

ownership for nonindustrial purposes (Rosson and London, 

1997). The rates of growth and removal (in board feet1 per year) 

of saw timber on undifferentiated privately held lands were much 

higher than corresponding rates on National Forest lands and 

other federal and state lands (U.S. Forest Service, 1995). 

The timber industry helped shape the land-cover changes 

in the Boston Mountains Ecoregion during the 27-year study 

period (1973–2000). The leading land-cover conversion in all 

the time periods was from forest to mechanically disturbed 

(table 4). The Boston Mountains Ecoregion experienced 

conversion of an estimated 590 km2 of forest to mechanically 

disturbed between 1973 and 2000. The second-leading 

conversion was from grassland/shrubland to forest, which was 

associated with forest regeneration. Similarly, the third-leading 

conversion of mechanically disturbed to grassland/shrubland 

was indicative of new tree growth that followed cutting for 

timber. Although land-cover changes in the ecoregion were 

associated largely with forestry practices and the timber 

industry, it is worth noting that forested land also was cleared 

for agricultural land use.

1A board foot (a unit of volume for measuring lumber) is equal to 30 cm by 

30 cm by 2.5 cm (12 in. × 12 in. × 1 in.) (Albritton, 2001).
Chapter 13—Boston Mountains Ecoregion 139

Table 1. Percentage of Boston Mountains Ecoregion land cover 

that changed at least one time during study period (1973–2000) and 

associated statistical error.

[Most sample pixels remained unchanged (94.5 percent), whereas 5.5 percent 

changed at least once throughout study period]

Number

of

changes

Percent

of

ecoregion

Margin

of error

(+/− %)

Lower

bound

(%)

Upper

bound

(%)

Standard

error

(%)

Relative

error

(%)

1 2.7 0.6 2.2 3.3 0.4 14.1

2 2.3 0.4 1.9 2.6 0.2 10.5

3 0.5 0.1 0.4 0.6 0.1 17.4

4 0.0 0.0 0.0 0.0 0.0 43.9

Overall 

spatial 

change

5.5 0.9 4.7 6.4 0.6 10.4

Table 2. Raw estimates of change in Boston Mountains Ecoregion land cover, computed for each of 

four time periods between 1973 and 2000, and associated error at 85-percent confidence level.

[Estimates of change per period normalized to annual rate of change for each period]

Period Total change

(% of ecoregion)

Margin of 

error

(+/− %)

Lower 

bound

(%)

Upper bound

(%)

Standard 

error

(%)

Relative 

error

(%)

Average rate

(% per year)

Estimate of change, in percent stratum

1973–1980 2.0 0.5 1.5 2.5 0.3 17.1 0.3

1980–1986 2.1 0.3 1.8 2.5 0.2 10.1 0.4

1986–1992 2.0 0.3 1.7 2.4 0.2 10.3 0.3

1992–2000 2.7 0.5 2.2 3.1 0.3 11.7 0.3

Estimate of change, in square kilometers

1973–1980 347 88 259 435 59 17.1 50

1980–1986 364 54 310 418 37 10.1 61

1986–1992 349 53 296 402 36 10.3 58

1992–2000 457 79 378 535 53 11.7 57
140 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Table 3. Estimated area (and margin of error) of each land-cover class in Boston Mountains Ecoregion, calculated five times between 

1973 and 2000. See appendix 3 for definitions of land-cover classifications.

Water Developed Mechanically 

disturbed Mining Barren Forest Grassland/Shrubland Agriculture Wetland

Nonmechanically 

disturbed

% +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/−

Area, in percent stratum

1973 1.3 0.8 0.9 0.7 0.3 0.2 0.0 0.0 0.0 0.0 77.5 3.5 0.7 0.4 19.3 3.3 0.0 0.0 0.0 0.0

1980 1.3 0.8 0.9 0.7 0.9 0.2 0.0 0.0 0.0 0.0 77.0 3.5 0.6 0.2 19.4 3.3 0.0 0.0 0.0 0.0

1986 1.2 0.8 1.0 0.7 0.6 0.1 0.0 0.0 0.0 0.0 77.1 3.5 0.6 0.1 19.5 3.4 0.0 0.0 0.0 0.0

1992 1.3 0.8 1.0 0.7 0.8 0.2 0.0 0.0 0.0 0.0 76.7 3.5 0.5 0.1 19.7 3.4 0.0 0.0 0.0 0.0

2000 1.3 0.8 1.0 0.7 1.4 0.4 0.0 0.0 0.0 0.0 75.8 3.6 0.4 0.1 20.0 3.4 0.0 0.0 0.0 0.0

Net

change 0.1 0.0 0.2 0.1 1.0 0.4 0.0 0.0 0.0 0.0 –1.7 0.5 –0.3 0.3 0.7 0.2 0.0 0.0 0.0 0.0

Gross

change 0.2 0.1 0.2 0.1 3.1 0.6 0.0 0.0 0.0 0.0 3.6 0.7 1.3 0.4 1.2 0.2 0.0 0.0 0.0 0.0

Area, in square kilometers

1973 216 142 150 114 56 26 1 1 2 3 13,220 602 121 60 3,295 569 7 4 0 0

1980 220 143 155 116 148 29 1 1 2 2 13,137 594 95 27 3,303 571 7 4 0 0

1986 213 141 168 124 95 22 1 1 2 2 13,153 604 100 24 3,329 574 7 4 0 0

1992 225 144 173 126 130 27 2 1 2 3 13,088 598 85 24 3,358 576 6 3 0 0

2000 225 144 176 126 231 73 2 1 2 3 12,932 609 76 23 3,417 574 6 3 0 0

Net

change 9 7 26 16 175 74 1 1 0 0 –288 91 –45 53 122 38 –1 1 0 0

Gross

change 28 22 30 16 526 95 1 1 1 1 615 125 218 64 213 28 1 1 0 0
Chapter 13—Boston Mountains Ecoregion 141

Table 4. Principal land-cover conversions in Boston Mountains Ecoregion, showing amount of area changed (and margin of error, 

calculated at 85-percent confidence level) for each conversion during each of four time periods and also during overall study period. 

See appendix 3 for definitions of land-cover classifications.

[Values given for “other” classes are combined totals of values for other land-cover classes not listed in that time period. Abbreviations: n/a, not applicable]

Period From class To class

Area 

changed

Margin of 

error

Standard 

error Percent of 

ecoregion

Percent of all 

changes (km2) (+/− km2) (km2)

1973–1980 Forest Mechanically disturbed 145 30 20 0.9 41.9

Grassland/Shrubland Forest 80 58 40 0.5 23.0

Mechanically disturbed Grassland/Shrubland 33 19 13 0.2 9.4

Forest Agriculture 29 18 12 0.2 8.4

Agriculture Grassland/Shrubland 24 12 8 0.1 6.9

Other Other 36 n/a n/a 0.2 10.4

Totals 347 2.0 100.0

1980–1986 Forest Mechanically disturbed 84 20 14 0.5 23.0

Grassland/Shrubland Forest 68 23 15 0.4 18.6

Mechanically disturbed Agriculture 52 18 12 0.3 14.3

Mechanically disturbed Grassland/Shrubland 49 13 9 0.3 13.4

Mechanically disturbed Forest 45 26 17 0.3 12.4

Other Other 67 n/a n/a 0.4 18.4

Totals 364 2.1 100.0

1986–1992 Forest Mechanically disturbed 130 27 18 0.8 37.3

Grassland/Shrubland Forest 69 16 11 0.4 19.7

Mechanically disturbed Agriculture 38 13 9 0.2 10.8

Mechanically disturbed Grassland/Shrubland 31 14 10 0.2 8.8

Agriculture Grassland/Shrubland 22 9 6 0.1 6.4

Other Other 59 n/a n/a 0.3 17.0

Totals 349 2.0 100.0

1992–2000 Forest Mechanically disturbed 231 73 49 1.4 50.6

Grassland/Shrubland Forest 52 16 11 0.3 11.5

Mechanically disturbed Agriculture 51 16 11 0.3 11.2

Mechanically disturbed Forest 41 18 12 0.2 9.1

Mechanically disturbed Grassland/Shrubland 38 13 9 0.2 8.3

Other Other 43 n/a n/a 0.3 9.4

Totals 457 2.7 100.0

1973–2000

(overall)

Forest Mechanically disturbed 590 102 69 3.5 38.9

Grassland/Shrubland Forest 269 88 59 1.6 17.7

Mechanically disturbed Grassland/Shrubland 150 44 30 0.9 9.9

Mechanically disturbed Agriculture 147 35 24 0.9 9.7

Mechanically disturbed Forest 115 53 36 0.7 7.6

Other Other 246 n/a n/a 1.4 16.2

Totals 1,517 8.9 100.0
142 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

References Cited

Albritton, T., 2001, Basic forest measurements: Alabama 

Forestry Commission, 1 p., accessed October 29, 2009, at 

http://216.226.177.78/Publications/TREASURED_Forest_Magazine/2001%20Summer/Basic%20Forest%20Measurements.pdf.

Anderson, J.R., Hardy, E.E., Roach, J.T., and Witmer, R.E., 

1976, A land use and land cover classification system for 

use with remote sensor data: U.S. Geological Survey Professional Paper 964, 41 p., available at http://pubs.er.usgs.

gov/publication/pp964.

Bentley, J.W., Johnson, T.G., and Howell, M., 2002, Arkansas’ 

timber industry—An assessment of timber product output 

and use, 1999: U.S. Forest Service, Southern Research Station, Resource Bulletin SRS-79, 41 p., accessed October 30, 

2013, at http://www.srs.fs.usda.gov/pubs/5261.

Guccione, M.J., 2008, Boston Mountains: The Encyclopedia 

of Arkansas History and Culture Web site, accessed December 3, 2009, at http://www.encyclopediaofarkansas.net/

encyclopedia/entry-detail.aspx?entryID=2389.

Donley, D.E., and Acciavatti, R.E., 1997, Red oak borer: U.S. 

Department of Agriculture, Forest Service, Forest Insect & 

Disease Leaflet 163, accessed December 3, 2013, at http://

www.na.fs.fed.us/spfo/pubs/fidls/red%20oak%20borer/

redoak.htm.

Heitzman, E., Grell, A., Spetich, M., and Starkey, D., 2007, 

Changes in forest structure associated with oak decline in 

severely impacted areas of northern Arkansas: Southern 

Journal of Applied Forestry, Society of American Foresters, 

v. 31, no. 1, p. 17–22.

National Park Service, 2013, Buffalo National River, Arkansas—Climate and geology: National Park Service database, 

accessed December 3, 2013, at http://www.nps.gov/buff/

naturescience/climate-and-geology.htm.

Omernik, J.M., 1987, Ecoregions of the conterminous United 

States: Annals of the Association of American Geographers, 

v. 77, no. 1, p. 118–125.

Petersen, J.C., Adamski, J.C., Bell, R.W., Davis, J.V., Femmer, 

S.R., Freiwald, D.A., and Joseph, R.L., 1998, Water quality 

in the Ozark Plateaus, Arkansas, Kansas, Missouri, and 

Oklahoma, 1992–95: U.S. Geological Survey Circular 1158, 

33 p., available at http://pubs.usgs.gov/circ/circ1158/. 

Reilly, T.E., Dennehy, K.F., Alley, W.M., and Cunningham, 

W.L., 2008, Ground-water availability in the United States: 

U.S. Geological Survey Circular 1323, p. 8–9, available at 

http://pubs.usgs.gov/circ/1323/.

Rosson, J.F., Jr., and London, J.D., 1997, Forest statistics for 

Arkansas’ Ozark counties—1995: U.S. Forest Service, 

Southern Research Station, Resource Bulletin SRS-15, p. 

1–4, accessed October 30, 2012, at http://www.srs.fs.usda.

gov/pubs/1635.

U.S. Census Bureau, 2001, Geographic area—Tahlequah city, 

Oklahoma, in Profiles of general demographic characteristics, 2000—2000 Census of Population and Housing – 

Oklahoma: U.S. Census Bureau database, p. 677, accessed 

December 3, 2013, at https://www.census.gov/prod/

cen2000/dp1/2kh40.pdf.

U.S. Department of Agriculture, 2006, Programmatic environmental assessment for implementation of the Conservation 

Reserve Enhancement Program Agreement for Oklahoma: 

U.S. Department of Agriculture, Farm Service Agency, 144 

p., accessed July 16, 2009, at http://www.fsa.usda.gov/Internet/FSA_File/ok_final_020408.pdf.

U.S. Forest Service, 1995, Forest Inventory and Analysis 

National Program: U.S. Forest Service database, accessed 

July 13, 2009, at http://www.fia.fs.fed.us/.

Van Sickle, C.C., 1970, Arkansas forest resource patterns: 

U.S. Forest Service, Southern Forest Experiment Station, p. 

1–34, accessed October 30, 2012, at http://www.srs.fs.usda.

gov/pubs/21703. 

Vogelmann, J.E., Howard, S.M., Yang, L., Larson, C.R., 

Wylie, B.K., and van Driel, N., 2001, Completion of the 

1990s National Land Cover Data Set for the conterminous 

United States from Landsat Thematic Mapper data and 

ancillary data sources: Photogrammetric Engineering & 

Remote Sensing, v. 67, p. 650–662.

Wiken, E., Jiménez Nava, F., and Griffith, G., 2011, North 

American terrestrial ecoregions—Level III: Montreal, 

Canada, Commission for Environmental Cooperation, 149 

p., accessed November 5, 2012, at http://www.cec.org/

Storage/133/15860_QA07.30-32_NP_NA_Terrestrial_

Ecoregions_Level_3_Final-2june11.pdf.

Woods, A.J., Foti, T.L., Chapman, S.S., Omernik, J.M., Wise, 

J.A., Murray, E.O., Prior, W.L., Pagan, J.B., Jr., Comstock, 

J.A., and Radford, M., 2004, Summary table—Characteristics of the ecoregions of Arkansas [back side], in Ecoregions 

of Arkansas: U.S. Geological Survey Ecoregion Map Series, 

accessed July 13, 2009, at http://www.epa.gov/wed/pages/

ecoregions/ar_eco.htm. 
Ecoregion boundary

Sample block (10 x 10 km)

Land-use/land-cover class

Water

Developed

Transitional

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Ice/Snow

EXPLANATION

36°

34°

96° 94° 92°

Ozark

Highlands

South

Central

Plains

Ouachita Moutains

Mississippi

Alluvial Plain

Mississippi

Alluvial Plain

Central

Irregular

Plains

COTP

TBP

Flint

Hills

Boston

Mountains

ARKANSAS

MISSOURI

OKLAHOMA

Booneville

Lake Dardanelle

Robert

S Kerr Eufaula Reservoir

Lake

Red Oak

Tulsa

OUACHITA MOUNTAINS

Hopewell

CLEBURNE

LOGAN COUNTY

COUNTY

Winrock

North

Little Rock

Arkoma

Fort

Smith

Canadian River

0 50 100 MILES

0 50 100 KILOMETERS

OK

AR

Arkansas Valley

Ecoregion

River

Ar kansas

Chapter 14

Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000 

Edited by Roger F. Auch and Krista A. Karstensen 

U.S. Geological Survey Professional Paper 1794–C, 2015

Arkansas Valley Ecoregion

By Krista A. Karstensen

Ecoregion Description 

The Arkansas Valley Ecoregion covers about 26,606 km2

(10,273 mi2) across west-central Arkansas and east-central 

Oklahoma (fig. 1) (Omernik, 1987; Wiken and others, 2011). 

Ecoregions that surround the Arkansas Valley Ecoregion are 

the Central Irregular Plains and Boston Mountains Ecoregions 

to the north, the Mississippi Alluvial Plain Ecoregion to the 

east, the Ouachita Mountains Ecoregion to the south, and the 

Central Oklahoma/Texas Plains Ecoregion to the west. The 

Arkansas Valley Ecoregion generally is characterized by plains, 

hills, floodplains, terraces, and scattered mountains (Woods 

and others, 2005), which differs from the neighboring Boston 

Mountains and Ouachita Mountains Ecoregions but is similar 

to the Mississippi Alluvial Plain Ecoregion to the east because 

both ecoregions include alluvial geology and bottomland plant 

communities (The Nature Conservancy, 2003).

The Arkansas Valley Ecoregion generally lies in a synclinal 

valley that essentially coincides with the Arkoma Basin, an 

oil-and-gas province that developed as layers of sand and mud 

were deposited in a depression during the Ouachita orogeny, a 

mountain-building period in the Paleozoic era that resulted in 

the landforms in the neighboring Ouachita Mountains to the 

south. Elevations in the Arkansas Valley Ecoregion range from 

Figure 1. Map of Arkansas Valley Ecoregion and surrounding ecoregions, showing land-use/land-cover classes from 1992 National 

Land Cover Dataset (Vogelmann and others, 2001); note that not all land-use/land-cover classes shown in explanation may be 

depicted on map; note also that, for this “Status and Trends of Land Change” study, transitional land-cover class was subdivided into 

mechanically disturbed and nonmechanically disturbed classes. Squares indicate locations of 10 x 10 km sample blocks analyzed 

in study. Index map shows locations of geographic features mentioned in text. Abbreviations for Midwest–South Central United 

States ecoregions are listed in appendix 2. Also shown are parts of two Great Plains ecoregions: Central Irregular Plains and Central 

Oklahoma/Texas Plains (COTP). See appendix 3 for definitions of land-use/land-cover classifications.
144 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

62 to 839 m (Woods and others, 2005) (fig. 2), and local relief 

ranges from less than 15 to 305 m (Woods and others, 2005). 

The two largest urban areas in the Arkansas Valley 

Ecoregion are Fort Smith and North Little Rock, Arkansas, 

with populations in 2000 of 80,268 and 60,433, respectively. 

Fort Smith was established in 1817 as an U.S. Army outpost, 

and the city continues to have an active military presence, 

although manufacturing, education, health care, and social 

services also are important to the economy (U.S. Census 

Bureau, 2009; City of Fort Smith, Arkansas, 2010).

The climate of the Arkansas Valley Ecoregion is affected by 

prevailing westerly winds, and weather systems generally move 

from west to east (Perry, 2005). Summers generally are hot, and 

winters are moderately cool, typically with no significant snow 

accumulation. Mean annual precipitation ranges from 1,040 to 

1,570 mm (41–62 in.) (Woods and others, 2005). 

Two primary river systems drain the Arkansas Valley 

Ecoregion, the Arkansas River and the Canadian River. The 

Arkansas River played an important role in westward expansion 

and the early settlement of the ecoregion. The largest lakes in 

the ecoregion—Eufaula Lake and Robert S Kerr Reservoir in 

Oklahoma and Lake Dardanelle in Arkansas—are all reservoirs 

0 12 24 36

Area, as percent of ecoregion

Ecoregion 

DA

HELP

CCBP

SMNIDP

NCHF

BM

IRL

SEWTP

OH

EDP

ECBP

NMW

AV

MAP

NLF

SCP

OM

EXPLANATION

Change in one time period

Change in two time periods

Change in three time periods

Change in four time periods

Change in four time periods

Figure 2. Valley near Winrock, Arkansas.

Figure 3. Hay field near Booneville, Arkansas.

Figure 4. Overall spatial change in Arkansas Valley Ecoregion 

(AV; darker bars) compared with that of all 17 Midwest–South 

Central United States ecoregions (lighter bars). Each horizontal 

set of bars shows proportions of ecoregion that changed during 

one, two, three, or four time periods; highest level of spatial 

change in Arkansas Valley Ecoregion (four time periods) labeled 

for clarity. See table 2 for years covered by each time period. See 

appendix 2 for key to ecoregion abbreviations.

along these two rivers, and they provide ideal conditions for 

fishing, camping, and other recreational activities. 

The forests of the Arkansas Valley Ecoregion are 

dominated by oak–hickory and oak–hickory–pine (Quercus 

spp., Carya spp., and Pinus spp.) woodlands (Woods and others, 

2005). Income from the timber industry is substantial, although, 

historically, such income was judged to be less than its full 

potential in some areas of the ecoregion (Brinlee and Wilson, 

1981), as some of the woodlands were cut several times, and the 

trees that were left to propagate the stands were of poor quality 

(Brinlee and Wilson, 1981; Swafford and Allgood, 1981). Two 

main differences in forest land cover exist between the Arkansas 

Valley Ecoregion and that of the neighboring Boston Mountains 

and Ouachita Mountains Ecoregions: (1) forest ownership in 

the Arkansas Valley Ecoregion primarily is private, with much 

less publicly held forest land, and (2) more forested land in the 

Arkansas Valley Ecoregion was cleared for agricultural land use 

than in the neighboring ecoregions (Karstensen, 2009). 

Although some of the wooded steep slopes in the 

ecoregion are used for woodland grazing, most of the 

pasturelands and hay lands are on the bottomlands and the 

more gently sloping upland areas (Woods and others, 2005) 

(fig. 3). Poultry and livestock production are important 

agricultural land uses, and extensive cropland is present in the 

Arkansas River floodplain (Woods and others, 2005).
Chapter 14—Arkansas Valley Ecoregion 145

0.5

0.0

1.0

1.5

2.5

3.0

2.0

3.5

1973 to 1980 1980 to 1986 1986 to 1992 1992 to 2000

Average annual change, as percent of ecoregion

Time period

−1

−0.5

0

0.5

1

1973–1980 1980–1986 

Time period

1986–1992 1992–2000 

Area changed, as percent of ecoregion 

Water

Developed

Mechanically disturbed

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Nonmechanically disturbed

Ice/Snow

EXPLANATION

LAND-USE/LAND-COVER CLASS

Figure 5. Estimates of land-cover change per time period, 

normalized to annual rates of change for all 17 Midwest–South 

Central United States ecoregions (gray bars). Estimates of change 

for Arkansas Valley Ecoregion are represented by red bars in 

each time period.

Figure 6. Normalized average net change in Arkansas Valley 

Ecoregion by time period for each land-cover class. Bars above 

zero axis represent net gain, whereas bars below zero represent 

net loss. Note that not all land-cover classes shown in explanation 

may be represented in figure. See appendix 3 for definitions of 

land-use and land-cover classifications.

Contemporary Land-Cover Change 

(1973 to 2000) 

 The overall spatial change (the percentage of land 

area that changed at least one time) in the Arkansas Valley 

Ecoregion between 1973 and 2000 is estimated at 8.3 

percent (table 1). Compared to other Midwest–South Central 

ecoregions, change in the Arkansas Valley Ecoregion was 

moderately high (fig. 4): about 5.8 percent of the ecoregion 

changed once during the study period, 2.1 percent changed 

twice, 0.4 percent changed three times, and 0.1 percent changed 

four times (table 1). The amount of change varied for each of 

the four time periods between 1973 and 2000, with the total 

change ranging from 2.3 to 3.4 percent of the ecoregion (table 

2). The average annual rate of change was highest during the 

third time period (1986–1992; 0.5 percent) and lowest during 

the first time period (1973–1980; 0.3 percent) (table 2; fig. 5). 

The forest and agriculture land-cover classes changed 

the most during the 27-year study period (table 3; fig. 6). 

Forest, which covered an estimated 12,868 km2 of the 

ecoregion in 2000, had a 3.7 percent (490 km2) decrease 

from its estimated 1973 area, a net loss of 1.8 percent of the 

ecoregion area. Forest loss in the ecoregion likely can be 

attributed to timber logging practices, as well as agricultural 

expansion. Agricultural land, which covered about 10,767 

km2 of the ecoregion in 2000, had a 1.2 percent decrease 

from its estimated 1973 area, a net loss of 0.5 percent of the 

ecoregion area. Although agriculture had a net gain from forest 

in the ecoregion, the overall force behind the small net loss 

of agriculture was the amount of agricultural land that was 

converted to developed land, an estimated 231 km2 (table 4). 

In 2000, forest was the dominant land-cover class in 

the Arkansas Valley Ecoregion (table 3). Most land-cover 

conversions associated with the forest were related to timberharvest logging practices, as shown by conversions from 

forest to mechanically disturbed and, to a lesser extent, from 

mechanically disturbed to grassland/shrubland (table 4). 

According to the U.S. Forest Service, the average potential 

productivity of the forests in the ecoregion was 73 cubic 

feet per acre in 1995, a value less than that of the Ouachita 

Mountains Ecoregion but more than that of the Boston 

Mountains Ecoregion (Rudis, 2001). Forested land in the 

Arkansas Valley Ecoregion also was cleared for agricultural 

expansion during the study period, a practice that has been 

occurring since the early days of settlement in the ecoregion. 

Although crop varieties, farm types and sizes, and certain 

management practices have changed across time, agriculture 

has long played an important role in the Arkansas Valley 

Ecoregion. For example, in Logan County, Arkansas, soils 

that have good natural drainage on hills and in valleys near 

the floodplain of the Arkansas River were cleared for farming, 

whereas steep, stony, or wet soils were left as woodland 
146 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Figure 7. Mechanical disturbance of forest near Red Oak, Oklahoma. Figure 8. Forest near Hopewell, in Cleburne County, Arkansas.

(Garner and others, 1980). Until 1980, cotton was considered a 

primary cash crop in the area (Garner and others, 1980); after 1980, 

farming practices became more diversified, with dairying and the 

raising of beef cattle, hogs, and poultry becoming more predominant 

(Garner and others, 1980). Livestock production has been a major 

source of income in areas of ridges and valleys, whereas soybean 

cultivation has been the major source of farm income in the 

bottomlands (Garner and others, 1980). Poultry farming increased 

around 1970, supporting an increase in livestock farming as litter 

from the poultry farms could be used as fertilizer on cattle fields 

(Robert Coats, University of Arkansas, oral commun., 2011).

The predominant land-cover changes in the Arkansas 

Valley Ecoregion can be attributed to the forestry and 

agricultural industries, as is shown in the ecoregion statistics 

in each of the four time periods (and in the overall 27-year 

study period); however, except for forest cutting, these 

changes did little to alter the overall land-cover composition 

of the ecoregion. Although both the forest and agriculture 

land-cover classes incurred an overall net loss between 1973 

and 2000, they remained the leading land-cover classes in the 

Arkansas Valley Ecoregion.
Chapter 14—Arkansas Valley Ecoregion 147

Table 2. Raw estimates of change in Arkansas Valley Ecoregion land cover, computed for each of four 

time periods between 1973 and 2000, and associated error at 85-percent confidence level.

[Estimates of change per period normalized to annual rate of change for each time period]

Period Total change

(% of ecoregion)

Margin of 

error

(+/− %)

Lower 

bound

(%)

Upper bound

(%)

Standard 

error

(%)

Relative 

error

(%)

Average rate

(% per year)

Estimate of change, in percent stratum

1973–1980 2.4 0.6 1.8 3.0 0.4 16.0 0.3

1980–1986 2.3 0.6 1.7 3.0 0.4 17.9 0.4

1986–1992 3.1 0.9 2.2 4.0 0.6 20.1 0.5

1992–2000 3.4 0.9 2.5 4.3 0.6 18.2 0.4

Estimate of change, in square kilometers

1973–1980 644 153 492 797 103 16.0 92

1980–1986 624 165 458 789 112 17.9 104

1986–1992 826 244 581 1,070 166 20.1 138

1992–2000 907 244 663 1,151 165 18.2 113

Table 1. Percentage of Arkansas Valley Ecoregion land cover 

that changed at least one time during study period (1973–2000) and 

associated statistical error.

[Most sample pixels remained unchanged (91.7 percent), whereas 8.3 percent 

changed at least once throughout study period]

Number

of

changes

Percent

of

ecoregion

Margin

of error

(+/− %)

Lower

bound

(%)

Upper

bound

(%)

Standard

error

(%)

Relative

error

(%)

1 5.8 0.8 5.0 6.6 0.5 9.3

2 2.1 0.8 1.3 2.9 0.6 26.4

3 0.4 0.3 0.0 0.7 0.2 61.9

4 0.1 0.1 0.0 0.1 0.0 56.0

Overall 

spatial 

change

8.3 1.4 6.9 9.7 1.0 11.5
148 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Table 3. Estimated area (and margin of error) of each land-cover class in Arkansas Valley Ecoregion, calculated five times 

between 1973 and 2000. See appendix 3 for definitions of land-cover classifications.

Water Developed

Mechanically 

disturbed

Mining Barren Forest Grassland/

Shrubland Agriculture Wetland

Nonmechanically 

disturbed

% +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/−

Area, in percent stratum

1973 2.0 1.1 2.3 1.2 0.4 0.2 0.1 0.1 0.1 0.1 50.2 4.2 3.1 1.5 40.9 4.4 0.8 0.3 0.0 0.0

1980 2.1 1.1 2.7 1.4 0.4 0.4 0.1 0.1 0.1 0.1 49.9 4.1 3.1 1.4 40.9 4.4 0.8 0.3 0.0 0.0

1986 2.1 1.1 3.0 1.5 0.4 0.3 0.2 0.1 0.1 0.0 49.6 4.1 3.1 1.4 40.7 4.4 0.8 0.3 0.0 0.0

1992 2.1 1.1 3.2 1.7 0.9 0.7 0.1 0.1 0.1 0.0 49.0 4.1 3.1 1.5 40.6 4.4 0.8 0.3 0.0 0.0

2000 2.1 1.1 3.6 1.8 0.8 0.3 0.2 0.1 0.1 0.1 48.4 4.0 3.6 1.7 40.5 4.3 0.8 0.3 0.0 0.0

Net

change 0.1 0.1 1.3 0.7 0.4 0.3 0.1 0.1 0.0 0.0 –1.8 1.0 0.5 0.7 –0.5 0.8 0.0 0.0 0.0 0.0

Gross

change 0.4 0.1 1.3 0.7 2.8 1.4 0.2 0.1 0.1 0.1 4.3 1.0 2.2 0.9 2.4 0.6 0.2 0.1 0.0 0.0

Area, in square kilometers

1973 540 303 613 328 94 46 33 25 35 19 13,358 1,122 821 390 10,895 1,176 218 77 0 0

1980 554 303 722 375 99 95 33 22 29 19 13,266 1,091 812 385 10,874 1,164 217 78 0 0

1986 559 303 789 399 116 72 48 25 20 12 13,196 1,092 830 380 10,826 1,163 222 77 0 0

1992 564 302 859 440 252 182 38 19 19 12 13,029 1,091 820 387 10,809 1,160 217 78 0 0

2000 562 301 961 489 207 88 48 22 24 14 12,868 1,059 953 457 10,767 1,140 216 80 0 0

Net

change 22 18 348 197 113 83 15 15 –11 9 –490 257 131 189 –127 210 –1 12 0 0

Gross

change 97 35 352 197 733 375 49 21 34 25 1,139 267 587 249 647 170 48 21 0 0
Chapter 14—Arkansas Valley Ecoregion 149

Table 4. Principal land-cover conversions in Arkansas Valley Ecoregion, showing amount of area changed (and margin of error, 

calculated at 85-percent confidence level) for each conversion during each of four time periods and also during overall study period. 

See appendix 3 for definitions of land-cover classifications.

[Values given for “other” class are combined totals of values for other land-cover classes not listed in that time period. Abbreviations: n/a, not applicable]

Period From class To class

Area 

changed

Margin of 

error

Standard 

error Percent of 

ecoregion

Percent of all 

changes (km2) (+/− km2) (km2)

1973–1980 Forest Agriculture 121 37 25 0.5 18.8

Forest Mechanically disturbed 98 95 65 0.4 15.2

Agriculture Developed 80 71 48 0.3 12.4

Grassland/Shrubland Forest 77 51 34 0.3 11.9

Mechanically disturbed Grassland/Shrubland 60 36 25 0.2 9.3

Other Other 209 n/a n/a 0.8 32.4

Totals 644 2.4 100.0

1980–1986 Forest Mechanically disturbed 112 70 48 0.4 18.0

Forest Agriculture 99 28 19 0.4 15.9

Grassland/Shrubland Forest 72 30 20 0.3 11.5

Agriculture Forest 60 38 26 0.2 9.6

Agriculture Grassland/Shrubland 49 32 22 0.2 7.9

Other Other 231 n/a n/a 0.9 37.0

Totals 624 2.3 100.0

1986–1992 Forest Mechanically disturbed 242 181 122 0.9 29.4

Forest Agriculture 116 26 18 0.4 14.0

Grassland/Shrubland Forest 100 58 39 0.4 12.2

Mechanically disturbed Forest 68 45 31 0.3 8.3

Agriculture Forest 57 34 23 0.2 6.9

Other Other 242 n/a n/a 0.9 29.3

Totals 826 3.1 100.0

1992–2000 Forest Mechanically disturbed 198 84 57 0.7 21.8

Mechanically disturbed Grassland/Shrubland 185 178 121 0.7 20.4

Forest Agriculture 111 30 21 0.4 12.2

Grassland/Shrubland Forest 85 49 33 0.3 9.4

Agriculture Developed 68 52 35 0.3 7.5

Other Other 260 n/a n/a 1.0 28.7

Totals 907 3.4 100.0

1973–2000

(overall)

Forest Mechanically disturbed 650 337 228 2.4 21.7

Forest Agriculture 446 84 57 1.7 14.9

Mechanically disturbed Grassland/Shrubland 337 232 157 1.3 11.2

Grassland/Shrubland Forest 334 117 79 1.3 11.1

Agriculture Developed 231 158 107 0.9 7.7

Other Other 1,001 n/a n/a 3.8 33.4

Totals 3,000 11.3 100.0
150 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

References Cited

Brinlee, R.C., and Wilson, R.C., 1981, Soil survey of Latimer 

County, Oklahoma: U.S. Department of Agriculture, Soil 

Conservation Service, p. 1–53, available at http://soils.usda.

gov/survey/printed_surveys/.

City of Fort Smith, Arkansas, 2010, City of Fort Smith, 

Arkansas: City of Fort Smith database, accessed May 12, 

2011, at http://www.fortsmithar.gov/.

Garner, B.A., Cox, J.B., Vodrazka, F.M., and Winfrey, 

A.L., 1980, Soil survey of Logan County, Arkansas: U.S. 

Department of Agriculture, Soil Conservation Service and 

Forest Service, p. 1–3, available at http://soils.usda.gov/

survey/printed_surveys/.

Karstensen, K.A., 2009, Land-cover change in the Boston 

Mountains, 1973–2000: U.S. Geological Survey Open-File 

Report 2009–1281, 10 p., available at http://pubs.usgs.gov/

of/2009/1281/.

Omernik, J.M., 1987, Ecoregions of the conterminous United 

States: Annals of the Association of American Geographers, 

v. 77, no. 1, p. 118–125. 

Perry, C.A., 2005, Summary of significant floods in the United 

States and Puerto Rico, 1994 through 1998 water years: 

U.S. Geological Survey Scientific Investigations Report 

2005–5194, 327 p., available at http://pubs.usgs.gov/

sir/2005/5194/.

Rudis, V.A., 2001, Landscape context and regional patterns in 

Arkansas’ forests: U.S. Forest Service, Southern Research 

Station, General Technical Report SRS 41, p. 24–45, 

accessed May 15, 2011, at http://www.srs.fs.usda.gov/

pubs/3097/.

Swafford, B.G., and Allgood, F.P., 1981, Soil survey of 

McIntosh County, Oklahoma: U.S. Department of 

Agriculture, Soil Conservation Service, p. 1–7, available at 

http://soils.usda.gov/survey/printed_surveys/.

The Nature Conservancy, 2003, Ozarks ecoregional conservation 

assessment: The Nature Conservancy, Ozarks Ecoregional 

Assessment Team, Midwestern Resource Office, 248 p., 

available at http://www.nature.org/ourinitiatives/regions/

northamerica/unitedstates/oklahoma/explore/ozarks-1.pdf.

U.S. Census Bureau, 2009, State and county quick facts—

North Little Rock (city), Arkansas: U.S. Census Bureau 

database, accessed May 12, 2011, at http://quickfacts.census.

gov/qfd/states/05/0550450. html.

Vogelmann, J.E., Howard, S.M., Yang, L., Larson, C.R., Wylie, 

B.K., and van Driel, N., 2001, Completion of the 1990s 

National Land Cover Data Set for the conterminous United 

States from Landsat Thematic Mapper data and ancillary 

data sources: Photogrammetric Engineering & Remote 

Sensing, v. 67, p. 650–662.

Wiken, E., Jiménez Nava, F., and Griffith, G., 2011, North 

American terrestrial ecoregions—Level III: Montreal, 

Canada, Commission for Environmental Cooperation, 149 

p., accessed November 5, 2012, at http://www.cec.org/

Storage/133/15860_QA07.30-32_NP_NA_Terrestrial_

Ecoregions_Level_3_Final-2june11.pdf.

Woods, A.J., Omernik, J.M., Butler, D.R., Ford, J.G., Henley, J.E., 

Hoagland, B.W., Arndt, D.S., and Moran, B.C., 2005, Summary 

table—Characteristics of the ecoregions of Oklahoma [back 

side], in Ecoregions of Oklahoma: U.S. Geological Survey 

Ecoregion Map Series, accessed August 2, 2010, at http://www.

epa.gov/wed/pages/ecoregions/ok_eco.htm.
Chapter 15

Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000 

Edited by Roger F. Auch and Krista A. Karstensen 

U.S. Geological Survey Professional Paper 1794–C, 2015

Ouachita Mountains Ecoregion

By Krista A. Karstensen

Ecoregion Description 

The Ouachita Mountains Ecoregion covers about 

26,506 km2 (10,234 mi2) across west-central Arkansas and 

southeastern Oklahoma (fig. 1) (Omernik, 1987; Wiken and 

others, 2011). The ecoregions neighboring the Ouachita 

Mountains Ecoregion are the Arkansas Valley Ecoregion to 

the north, the South Central Plains Ecoregion to the south, 

and the Central Oklahoma/Texas Plains Ecoregion to the 

west. The vegetation along the west edge of the ecoregion 

is dynamic, with pine–oak-forest (Pinus spp. and Quercus

spp.), tallgrass-prairie, and oak-savanna communities of the 

neighboring ecoregions to the west meeting along this edge 

(The Nature Conservancy, 2003). The boundaries of this 

“floristic association intergrade” advance and retreat with 

historic changes in climate (The Nature Conservancy, 2003).

Large urban areas are not common in the Ouachita 

Mountains Ecoregion. Hot Springs, Arkansas, which lies in 

the southeastern part of the ecoregion, is home to Hot Springs 

National Park, and the city had a population of 35,750 in 2000 

Figure 1. Map of Ouachita Mountains Ecoregion and surrounding ecoregions, showing land-use/land-cover classes from 1992 

National Land Cover Dataset (Vogelmann and others, 2001); note that not all land-use/land-cover classes shown in explanation may be 

depicted on map; note also that, for this “Status and Trends of Land Change” study, transitional land-cover class was subdivided into 

mechanically disturbed and nonmechanically disturbed classes. Squares indicate locations of 10 x 10 km sample blocks analyzed in 

study. Index map shows locations of geographic features mentioned in text. Abbreviations for Midwest–South Central United States 

ecoregions are listed in appendix 2. Also shown are parts of two Great Plains ecoregions: Central Oklahoma/Texas Plains (COTP) and 

Central Irregular Plains. See appendix 3 for definitions of land-use/land-cover classifications.

OK AR

Ouachita Moutains

Ecoregion

92°

94° 92°

96°

36°

34°

Ozark Highlands

South Central

Plains

Arkansas Valley

Mississippi

Alluvial

Plain

Central

Irregular

Plains

COTP

OH

Boston Mountains

0 50 100 MILES

0 50 100 KILOMETERS Ecoregion boundary

Sample block (10 x 10 km)

Land-use/land-cover class

Water

Developed

Transitional

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Ice/Snow

ARKANSAS EXPLANATION

OKLAHOMA

TEXAS

Broken

Bow Lake Hugo Lake R e d R i v e r

Lake

Greeson

De Gray

Lake 

Lake

Ouachita

HOT

SPRINGS

NATIONAL

PARK

Hot Springs

Fourche LaFave River

Kiamichi River

O U A C H I T A M O U N T A I N S

Lake Hamilton

O u a c h i t a R .

Lake Maumelle

Wister Lake Little

Rock

Arkansas River

Canadian River

S a line River
152 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

(U.S. Census Bureau, 2013). Hot Springs and its satellite 

retirement communities bring urbanization and recreational 

pressures to the nearby Saline River and Lake Ouachita (The 

Nature Conservancy, 2003). The other major urban area in 

the ecoregion is part of metropolitan Little Rock, Arkansas 

(population, 583,845 in 2000; U.S. Census Bureau, 2001), 

whose west edge is in the far-east corner of the ecoregion. 

Elevations in the Ouachita Mountains Ecoregion, which 

range from 88 to 823 m (Woods and others, 2004), are much 

higher than those of all of the neighboring ecoregions except 

for the Arkansas Valley Ecoregion, where elevations are 

comparable (table 1) (Woods and others, 2004, 2005). Overall, 

the local relief in the Ouachita Mountains Ecoregion, which 

ranges from 15 to 488 m, is much greater than that of its 

neighboring ecoregions (table 1) (Woods and others, 2004, 

2005). The landforms of the Ouachita Mountains Ecoregion 

are rooted in an accretionary wedge composed of intensely 

folded and deformed sandstone, shale, and chert that make 

up one of the major fold-and thrust-belt mountain ranges of 

North America (The Nature Conservancy, 2003). During the 

Paleozoic era, in the mountain-building period referred to as 

the Ouachita orogeny, an ocean closed as the South American 

plate collided with the North American plate, and mountains 

were formed as the intervening marine sediments were folded 

and faulted (The Nature Conservancy, 2003; Woods and 

others, 2004). 

The Ouachita Mountains Ecoregion is in the humidsubtropical climate zone. The climate of the ecoregion is 

affected by two different air masses: (1) warm, moist air 

moving north from the Gulf of Mexico, and (2) cool, dry 

air moving east from the central Great Plains (The Nature 

Conservancy, 2003). Summers generally are hot, and winters 

are moderately cool, typically with no significant snow 

accumulation. Mean annual precipitation ranges from 1,270 

to 1,680 mm (50–66 in.), increasing from west to east (The 

Nature Conservancy, 2003; Woods and others, 2004). Areas of 

higher elevation receive more rainfall because of orographic 

effects. Moderate droughts occur at 15- to 20-year intervals, 

and floods may occur in any month but are most common in 

the spring (The Nature Conservancy, 2003).

Several river systems drain the Ouachita Mountains 

Ecoregion, including the Arkansas, Kiamichi, Ouachita, 

Fourche LaFave, and Saline Rivers. Lakes in the ecoregion, 

which are mostly reservoirs, include Lake Ouachita, Lake 

Maumelle, De Gray Lake, Broken Bow Lake, Wister Lake, 

Lake Hamilton, Lake Catherine, and Lake Greeson. These 

waters provide ideal conditions for fishing, camping, and other 

recreational activities. The exceptional water quality of most 

hydrologic reaches in the ecoregion has provided habitat for 

various endemic species (The Nature Conservancy, 2003; 

Woods and others, 2004). 

Land cover in the Ouachita Mountains Ecoregion is 

composed primarily of loblolly pine (Pinus taeda) and 

shortleaf pine (Pinus echinata) forests (fig. 2). Although forest 

composition has changed across time, forest still remains 

the dominant land-cover class in the ecoregion. The most 

significant historical change in forest composition was the 

conversion of shortleaf pine forests to loblolly pine plantations 

on industrial lands (Hedrick and others, 2007). Throughout 

the ecoregion, the understory vegetation also has changed 

from grasses and forbs to woody species (Hedrick and 

others, 2007). Forest conditions at the beginning of the 21st 

century stem from two primary factors: (1) the cutting of the 

original trees, and (2) the effects of more than 60 years of firesuppression efforts (Hedrick and others, 2007). Large-scale 

exploitation of the original forests began in the early 1910s 

and had largely ended by the 1940s (Smith, 1986). Under 

U.S. Forest Service stewardship, the period of regeneration 

that followed the cutting was marked by a strict policy of 

fire suppression that continued well into the 1980s, resulting 

in the near-disappearance of the shortleaf pine–bluestem 

(Andropogon spp.) woodland community in the ecoregion by 

Figure 2. Map of Ouachita Mountains Ecoregion and surrounding ecoregions, showing types of forest land cover 

in 2002 (National Atlas of the United States, 2002). Squares indicate locations of 10 x 10 km sample blocks analyzed in 

study. Abbreviations for Midwest–South Central United States ecoregions are listed in appendix 2. Also shown are parts 

of one Great Plains ecoregion, Central Oklahoma/Texas Plains (COTP).

Arkansas Valley

South Central Plains

COTP

MAP

96° 95° 94° 93°

35°

34°

Forest type

EXPLANATION

Loblolly–shortleaf pine

Oak–pine

Oak–hickory

Oak–gum–cypress

Nonforest areas

Water

Ecoregion boundary

Sample block (10 x 10 km)

0 50 MILES

0 50 KILOMETERS
Chapter 15—Ouachita Mountains Ecoregion 153

the 1970s (Arkansas Department of Planning, 1974; Smith, 

1986; Hedrick and others, 2007).

Although not as widespread and dominant as forest, 

agriculture plays a role in the land uses of the Ouachita 

Mountains Ecoregion. Limited to valley bottoms, the 

agricultural land uses in the ecoregion primarily are hay lands 

and pasturelands used for cattle production. Poultry production 

also is important, and confined-feeding operations for raising 

fowl are common in the ecoregion. 

Contemporary Land-Cover Change 

(1973 to 2000)

The overall spatial change (the percentage of land area 

that changed at least one time) in the Ouachita Mountains 

Ecoregion between 1973 and 2000 is an estimated 33.9 

percent (table 2). The Ouachita Mountains Ecoregion not 

only had the highest overall spatial change of all 17 Midwest–

South Central ecoregions (fig. 3), but it also ranked highest 

in overall spatial change of all 84 Level III ecoregions of the 

conterminous United States (see appendix 1; see also, U.S. 

Environmental Protection Agency, 1999): about 10.4 percent 

of the ecoregion changed once during the study period, 18.2 

percent changed twice, 4.7 percent changed three times, and 

0.7 percent changed four times (table 2). 

0 12 24 36

Area, as percent of ecoregion

Ecoregion 

DA

HELP

CCBP

SMNIDP

NCHF

BM

IRL

SEWTP

OH

EDP

ECBP

NMW

AV

MAP

NLF

SCP

OM

EXPLANATION

Change in one time period

Change in two time periods

Change in three time periods

Change in four time periods

Change in four time periods

0.5

0.0

1.0

1.5

2.5

3.0

2.0

3.5

1973 to 1980 1980 to 1986 1986 to 1992 1992 to 2000

Average annual change, as percent of ecoregion

Time period

Figure 3. Overall spatial change in Ouachita Mountains 

Ecoregion (OM; darker bars) compared with that of all 17 

Midwest–South Central United States ecoregions (lighter bars). 

Each horizontal set of bars shows proportions of ecoregion that 

changed during one, two, three, or four time periods; highest level 

of spatial change in Ouachita Mountains Ecoregion (four time 

periods) labeled for clarity. See table 3 for years covered by each 

time period. See appendix 2 for key to ecoregion abbreviations.

Figure 4. Estimates of land-cover change per time period, 

normalized to annual rates of change for all 17 Midwest–South 

Central United States ecoregions (gray bars). Estimates of change 

for Ouachita Mountains Ecoregion are represented by red bars in 

each time period.

The amount of change varied between 1973 and 2000, 

with the total estimated change of any individual time 

period (as percent of ecoregion area) ranging from 12.5 to 

19.0percent (table 3). The average annual rates of change 

were highest during the middle two time periods (1980–1986, 

1986–1992), at 3.2 and 2.9 percent, respectively (table 3; 

fig. 4). Overall, land-cover change was the greatest in the

second time period (1980–1986) before decreasing slightly in 

the later time periods.

The forest and mechanically disturbed land-cover classes 

changed most during the study period (1973–2000) (table 4; 

fig. 5). Although forest still covered an estimated 20,602 km2

of the ecoregion in 2000, forest had a net loss of 5.7 percent of 

the ecoregion’s area (1,508 km2, a 6.8 percent decrease from 

its 1973 area) (table 4; fig. 6). Forest loss in the ecoregion 

likely can be attributed to the logging practices associated with 

the mechanically disturbed land-cover class. Mechanically 

disturbed land covered about 1,979 km2 in 2000, and it had 

a net gain of 3.4 percent of the ecoregion’s area (an 85.1 

percent increase from its 1973 area). Agriculture and water 

were the third and fourth most extensive land-cover classes 

in 2000, covering 2,286 km2 and 895 km2 of the ecoregion, 

respectively (table 4). 

The four leading land-cover conversions in the Ouachita 

Mountains Ecoregion between 1973 and 2000 were the 

following: (1) forest to mechanically disturbed (fig. 7), (2) 

mechanically disturbed to forest, (3) grassland/shrubland to 

forest, and (4) mechanically disturbed to grassland/shrubland 

(table 5). These land-cover-change statistics show typical 

land-cover responses to the land-use demands of the logging 

and timber industry. 
154 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Forest harvest plays a large role in the geographic and 

social aspects of the ecoregion, and the timber industry 

was the largest economic force in the Ouachita Mountains 

Ecoregion during the study period. By the late 1920s, forests 

in the ecoregion were logged completely, and second-growth 

forests were logged again in the 1940s and 1950s (The Nature 

Conservancy, 2003). This second-growth logging may have 

provided the baseline for the forest land-cover class that was 

mapped during the first time period (1973–1980) because 

the trees that were cut in the 1950s would have been mature 

and ready for harvest in the time period between 1973 and 

1980 (or in subsequent time periods). In 2000, the Ouachita 

Mountains still were dominated by forests, but the structure 

and composition of these forests had changed substantially 

(Bukenhofer and Hedrick, 2008). Although timber harvesting 

played an important role in shaping land-use/land-cover change 

in the Ouachita Mountains Ecoregion, it also is important to 

note the changes in management practices, as well as in forest 

composition, that occurred during the study period. 

Figure 6. Forest in Ouachita Mountains Ecoregion. Forest made 

up about 77.7 percent of land cover in ecoregion in 2000.

Figure 7. Logging activity in Ouachita Mountains Ecoregion, 

showing example of land cover that changed from forest to 

mechanically disturbed. 

Recent (1989, 2005, and 2008) U.S. Forest Service forest 

inventory surveys concluded that most of the forest land in the 

Ouachita Mountains Ecoregion is in private holdings (U.S. 

Forest Service, 2010).The next leading land owner is the U.S. 

Forest Service, followed by other federal agencies and state 

and local governments. Reserved status land in the ecoregion 

primarily was held by the U.S. Forest Service, the U.S. 

Fish and Wildlife Service, and the Departments of Defense 

and Energy (U.S. Forest Service, 2010). In the Ouachita 

Mountains Ecoregion, the distribution of land ownership 

in Arkansas was slightly different from that in Oklahoma. 

Although large timber corporations own most of the land in 

both states, slightly more private land is held in Oklahoma 

than in Arkansas, whereas more land is federally managed in 

Arkansas than in Oklahoma (The Nature Conservancy, 2003; 

U.S. Forest Service, 2010).

−8

−6

−4

−2

0

4

2

6

8

1973–1980 1980–1986 

Time period

1986–1992 1992–2000 

Area changed, as percent of ecoregion 

Water

Developed

Mechanically disturbed

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Nonmechanically disturbed

Ice/Snow

EXPLANATION

LAND-USE/LAND-COVER CLASS

Figure 5. Normalized average net change in Ouachita Mountains 

Ecoregion by time period for each land-cover class. Bars above 

zero axis represent net gain, whereas bars below zero represent 

net loss. Note that not all land-cover classes shown in explanation 

may be represented in figure. See appendix 3 for definitions of 

land-use and land-cover classifications.
Chapter 15—Ouachita Mountains Ecoregion 155

Figure 8. Pine plantation in Ouachita Mountains Ecoregion, 

showing trees of two different ages.

During the study period, forests in the ecoregion 

developed largely in response to the following two factors: (1) 

the commercial management of the original forests, and (2) the 

suppression of fires in the forests (Bukenhofer and Hedrick, 

2008). Large-scale harvesting of timber started in the 1910s, 

and, by 1940, most of the original forests had been cut (Smith, 

1986). Lead by U.S. Forest Service initiatives, the forest 

regeneration that followed this period of timber harvesting was 

marked by a strict policy of wildfire suppression (Bukenhofer 

and Hedrick, 2008), which remained largely in effect into 

the beginning of the 21st century (Bukenhofer and Hedrick, 

2008). The use of prescribed fire by managers during the late 

1990s and early 2000s (on an amount of area that averaged 

101 km2 annually) has been insufficient to maintain a restored 

(that is, in a pre–logged state) woodland ecosystem in the 

ecoregion, which then detrimentally affects the health and 

resiliency of other ecosystems in the ecoregion (Bukenhofer 

and Hedrick, 2008). 

The alteration of stand composition and structure also 

can affect the forest ecosystem. Between about 1983 and 

2003, changes in the Ouachita Mountains Ecoregion were 

manifested through second-growth forest that mostly was 

converted to pine plantations (The Nature Conservancy, 2003; 

see also, fig. 8). These plantations are composed primarily of 

“improved” loblolly pine, which is not native to the forestedupland ecosystems of the Ouachita Mountains Ecoregion.

Although forest thinning, selective cutting, and 

clearcutting have played a large role in the fragmentation of 

forests in the Ouachita Mountains Ecoregion, roads also have 

contributed significantly to this process. Roads constructed to 

access forest land can fragment the landscape and contribute 

to increased sedimentation in streams. However, many roads 

in the Ouachita Mountains ecoregion were smaller than the 

minimum mapping unit (60 x 60 m pixel) and, thus, may not 

be included in the statistics of the ecoregion. Nevertheless, 

roads played a vital role in certain activities in the ecoregion, 

such as timber harvesting. 

The dominant changes in the Ouachita Mountains 

Ecoregion involved the forest land-cover class, as shown in 

the land-cover-conversion statistics in table 4: in three of four 

time periods, the largest percentage of change was from forest 

to mechanically disturbed. These changes can be attributed 

to timber operations (timber harvesting and certain forestry 

practices), which played a large role in shaping the economic, 

social, and geographic composition of the ecoregion. Typical 

conversions associated with timber and forestry practices are 

from forest to mechanically disturbed and from grassland/

shrubland to forest, both of which occurred in each time 

period (table 4). Overall, forest remained the leading landcover class in the ecoregion (in terms of areal extent). 

Ecoregion Range in 

elevation (m)

Range in 

relief (m)

Ouachita Mountains Ecoregion 88 to 823 15 to 488

South Central Plains Ecoregion 15 to 168 3 to 107

Central Oklahoma/Texas Plains Ecoregion 183 to 518 15 to 107

Arkansas Valley Ecoregion 76 to 839 >15 to 183

Table 1. Ranges in elevation and in relief for Ouachita Mountains 

Ecoregion, compared to those for neighboring ecoregions.

[Note that Central Oklahoma/Texas Plains Ecoregion is not in Midwest–South 

Central United States group of ecoregions but, rather, is in Great Plains of the 

United States group]

Table 2. Percentage of Ouachita Mountains Ecoregion land 

cover that changed at least one time during study period (1973–

2000) and associated statistical error.

[Most sample pixels remained unchanged (66.1 percent), whereas 33.9percent 

changed at least once throughout study period]

Number

of

changes

Percent

of

ecoregion

Margin

of error

(+/− %)

Lower

bound

(%)

Upper

bound

(%)

Standard

error

(%)

Relative

error

(%)

1 10.4 1.8 8.6 12.1 1.2 11.5

2 18.2 3.2 15.0 21.4 2.2 11.8

3 4.7 1.0 3.6 5.7 0.7 14.8

4 0.7 0.4 0.3 1.1 0.3 42.3

Overall 

spatial 

change

33.9 5.2 28.7 39.0 3.5 10.3
156 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Table 3. Raw estimates of change in Ouachita Mountains Ecoregion land cover, computed for each of 

four time periods between 1973 and 2000, and associated error at 85-percent confidence level.

[Estimates of change per period normalized to annual rate of change for each period]

Period Total change

(% of ecoregion)

Margin of 

error

(+/− %)

Lower 

bound

(%)

Upper bound

(%)

Standard 

error

(%)

Relative 

error

(%)

Average rate

(% per year)

Estimate of change, in percent stratum

1973–1980 12.5 2.1 10.3 14.6 1.4 11.5 1.8

1980–1986 19.0 3.3 15.7 22.3 2.2 11.7 3.2

1986–1992 17.2 2.7 14.4 19.9 1.9 10.8 2.9

1992–2000 14.8 2.6 12.2 17.3 1.7 11.8 1.8

Estimate of change, in square kilometers

1973–1980 3,303 560 2,743 3,863 379 11.5 472

1980–1986 5,029 870 4,159 5,899 589 11.7 838

1986–1992 4,551 727 3,824 5,279 493 10.8 759

1992–2000 3,915 683 3,231 4,598 463 11.8 489

Table 4. Estimated area (and margin of error) of each land-cover class in Ouachita Mountains Ecoregion, calculated five times 

between 1973 and 2000. See appendix 3 for definitions of land-cover classifications.

Water Developed Mechanically 

disturbed Mining Barren Forest Grassland/Shrubland Agriculture Wetland

Nonmechanically 

disturbed

% +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/−

Area, in percent stratum

1973 3.2 2.3 0.5 0.3 4.0 1.0 0.0 0.0 0.1 0.1 83.4 2.7 1.0 0.4 7.6 2.0 0.2 0.1 0.0 0.0

1980 3.4 2.3 0.5 0.4 8.8 1.8 0.0 0.0 0.1 0.1 77.3 2.6 1.7 0.6 8.0 2.1 0.2 0.1 0.0 0.0

1986 3.4 2.3 0.6 0.4 9.8 1.8 0.0 0.0 0.1 0.1 74.5 2.9 3.2 0.8 8.1 2.2 0.2 0.1 0.0 0.0

1992 3.4 2.3 0.7 0.4 5.2 1.1 0.0 0.0 0.1 0.1 79.3 2.8 2.8 1.1 8.3 2.2 0.2 0.1 0.0 0.0

2000 3.4 2.3 0.7 0.4 7.5 1.8 0.0 0.0 0.1 0.1 77.7 2.7 1.6 0.8 8.6 2.3 0.2 0.1 0.1 0.1

Net

change 0.1 0.1 0.3 0.2 3.4 1.6 0.0 0.0 0.0 0.0 –5.7 1.5 0.7 0.7 1.1 0.6 0.0 0.0 0.1 0.1

Gross

change 0.2 0.1 0.3 0.2 19.1 3.3 0.0 0.0 0.0 0.0 21.4 3.5 6.6 1.5 1.2 0.6 0.0 0.0 0.1 0.1

Area, in square kilometers

1973 856 608 122 83 1,069 275 8 6 28 32 22,110 703 258 99 2,003 537 53 30 0 0

1980 892 613 139 94 2,338 473 10 6 26 28 20,486 686 450 147 2,112 564 53 30 0 0

1986 900 613 156 98 2,605 464 12 6 24 28 19,744 758 856 224 2,155 576 53 30 0 0

1992 898 606 173 102 1,387 301 12 5 25 28 21,013 754 748 301 2,197 587 54 30 0 0

2000 895 605 192 113 1,979 474 13 6 30 31 20,602 704 437 209 2,286 623 55 31 17 16

Net

change 39 38 71 47 910 415 5 4 2 3 –1,508 408 179 196 284 172 2 2 17 16

Gross

change 65 39 71 47 5,070 873 8 4 13 10 5,668 934 1,737 387 330 169 3 3 17 16
Chapter 15—Ouachita Mountains Ecoregion 157

Table 5. Principal land-cover conversions in Ouachita Mountains Ecoregion, showing amount of area changed (and margin of error, 

calculated at 85-percent confidence level) for each conversion during each of four time periods and also during overall study period. 

See appendix 3 for definitions of land-cover classifications.

[Values given for “other” class are combined totals of values for other land-cover classes not listed in that time period. Abbreviations: n/a, not applicable]

Period From class To class

Area 

changed

Margin of 

error

Standard 

error Percent of 

ecoregion

Percent of all 

changes (km2) (+/− km2) (km2)

1973–1980 Forest Mechanically disturbed 2,134 394 267 8.1 64.6

Mechanically disturbed Forest 542 158 107 2.0 16.4

Mechanically disturbed Grassland/Shrubland 314 126 86 1.2 9.5

Grassland/Shrubland Forest 117 68 46 0.4 3.5

Forest Water 19 22 15 0.1 0.6

Other Other 177 n/a n/a 0.7 5.4

Totals 3,303 12.5 100.0

1980–1986 Forest Mechanically disturbed 2,438 463 314 9.2 48.5

Mechanically disturbed Forest 1,482 361 245 5.6 29.5

Mechanically disturbed Grassland/Shrubland 686 184 124 2.6 13.6

Grassland/Shrubland Forest 288 124 84 1.1 5.7

Forest Agriculture 59 31 21 0.2 1.2

Other Other 76 n/a n/a 0.3 1.5

Totals 5,029 19.0 100.0

1986–1992 Mechanically disturbed Forest 2,116 416 282 8.0 46.5

Forest Mechanically disturbed 1,313 295 200 5.0 28.8

Grassland/Shrubland Forest 543 116 79 2.0 11.9

Mechanically disturbed Grassland/Shrubland 425 144 97 1.6 9.3

Forest Agriculture 64 30 20 0.2 1.4

Other Other 91 n/a n/a 0.3 2.0

Totals 4,551 17.2 100.0

1992–2000 Forest Mechanically disturbed 1,889 455 308 7.1 48.3

Mechanically disturbed Forest 1,122 274 185 4.2 28.7

Grassland/Shrubland Forest 500 184 125 1.9 12.8

Mechanically disturbed Grassland/Shrubland 184 72 48 0.7 4.7

Forest Agriculture 112 71 48 0.4 2.9

Other Other 108 n/a n/a 0.4 2.8

Totals 3,915 14.8 100.0

1973–2000

(overall)

Forest Mechanically disturbed 7,773 1,337 906 29.3 46.3

Mechanically disturbed Forest 5,263 1,017 689 19.9 31.3

Mechanically disturbed Grassland/Shrubland 1,608 392 266 6.1 9.6

Grassland/Shrubland Forest 1,447 341 231 5.5 8.6

Forest Agriculture 356 184 125 1.3 2.1

Other Other 350 n/a n/a 1.3 2.1

Totals 16,798 63.4 100.0
158 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

References Cited

Arkansas Department of Planning, 1974, Arkansas natural area 

plan: Fayetteville, The University of Arkansas Press, 265 p.

Bukenhofer, G.A., and Hedrick, L.D., 2008, Shortleaf 

pine/bluestem grass ecosystem renewal in the Ouachita 

Mountains: U.S. Forest Service database, accessed February 

15, 2013, at http://www.fs.usda.gov/detailfull/ouachita/home

/?cid=fsm9_039689&width=full.

Hedrick, L.D., Bukenhofer, G.A., Montague, W.G., Pell, W.F., 

and Guldin, J.M., 2007, Shortleaf pine-bluestem restoration 

in the Ouachita National Forest: U.S. Forest Service, 

Southern Research Station, Publication 31513, p. 206–213, 

accessed February 15, 2013, at http://www.srs.fs.usda.gov/

pubs/ja/ja_hedrick002.pdf.

National Atlas of the United States, 2002, Map layer info—

Forest cover types: National Atlas of the United States 

database, accessed August 2, 2010, at http://nationalatlas.

gov/mld/foresti.html.

Omernik, J.M., 1987, Ecoregions of the conterminous United 

States: Annals of the Association of American Geographers, 

v. 77, no. 1, p. 118–125.

Smith, K.L., 1986, Sawmill—The story of the cutting of the 

last great virgin forest east of the Rockies: Fayetteville, 

University of Arkansas Press, 246 p.

The Nature Conservancy, 2003, Ouachita Mountains 

assessment: Little Rock, The Nature Conservancy, Arkansas 

Field Office, Ozarks Ecoregional Assessment Team, 231 p.

U.S. Census Bureau, 2001, Metropolitan areas ranked by 

population—2000, table 3 in Ranking tables for metropolitan 

areas—Population in 2000 and population change from 1990 

to 2000 (PHC-T-3): U.S. Census Bureau database, accessed 

December 9, 2013, at http://www.census.gov/population/

www/cen2000/briefs/phc-t3/index.html.

U.S. Census Bureau, 2013, American FactFinder—Hot Springs 

city, Arkansas: U.S. Census Bureau database, accessed 

February 25, 2013, at http://factfinder2.census.gov/faces/

tableservices/jsf/pages/productview.xhtml?src=bkmk.

U.S. Environmental Protection Agency, 1999, Level 

III ecoregions of the continental United States: U.S. 

Environmental Protection Agency National Health 

and Environmental Effects Research Laboratory, scale 

1:7,500,000, available at ftp://ftp.epa.gov/wed/ecoregions/

usgs/useco_March1999_v5.pdf.

U.S. Forest Service, 2010, Forest Inventory and Analysis 

National Program: U.S. Forest Service database, accessed 

August 12, 2010, at http://www.fia.fs.fed.us/tools-data/

default.asp.

Vogelmann, J.E., Howard, S.M., Yang, L., Larson, C.R., 

Wylie, B.K., and van Driel, N., 2001, Completion of the 

1990s National Land Cover Data Set for the conterminous 

United States from Landsat Thematic Mapper data and 

ancillary data sources: Photogrammetric Engineering & 

Remote Sensing, v. 67, p. 650–662.

Wiken, E., Jiménez Nava, F., and Griffith, G., 2011, North 

American terrestrial ecoregions—Level III: Montreal, 

Canada, Commission for Environmental Cooperation, 149 

p., accessed November 5, 2012, at http://www.cec.org/

Storage/133/15860_QA07.30-32_NP_NA_Terrestrial_

Ecoregions_Level_3_Final-2june11.pdf.

Woods, A.J., Foti, T.L., Chapman, S.S., Omernik, J.M., Wise, 

J.A., Murray, E.O., Prior, W.L., Pagan, J.B., Jr., Comstock, 

J.A., and Radford, M., 2004, Ecoregions of Arkansas: 

U.S. Geological Survey Ecoregion Map Series, scale 

1:1,000,000, available at http://www.epa.gov/wed/pages/

ecoregions/ar_eco.htm.

Woods, A.J., Omernik, J.M., Butler, D.R., Ford, J.G., 

Henley, J.E., Hoagland, B.W., Arndt, D.S., and Moran, 

B.C., 2005, Ecoregions of Oklahoma: U.S. Geological 

Survey Ecoregion Map Series, scale 1:1,250,000, 

available at http://www.epa.gov/wed/pages/ecoregions/

ok_eco.htm.
South Central Lowlands Ecoregions

Chapter 16

Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000 

Edited by Roger F. Auch and Krista A. Karstensen 

U.S. Geological Survey Professional Paper 1794–C, 2015

Mississippi Alluvial Plain Ecoregion 

By Kristi L. Sayler

Figure 1. Map of Mississippi Alluvial Plain Ecoregion and surrounding ecoregions, showing land-use/land-cover classes from 1992 

National Land Cover Dataset (Vogelmann and others, 2001); note that not all land-use/land-cover classes shown in explanation may be 

depicted on map; note also that, for this “Status and Trends of Land Change” study, transitional land-cover class was subdivided into 

mechanically disturbed and nonmechanically disturbed classes. Squares indicate locations of 10 x 10 km sample blocks analyzed in 

study. Index map shows locations of geographic features mentioned in text. Abbreviations for Midwest–South Central United States 

ecoregions are listed in appendix 2. Also shown are parts of one Great Plains ecoregion (Western Gulf Coastal Plain [WGCP]) and 

three Eastern United States ecoregions (Mississippi Valley Loess Plains [MVLP], Southeastern Plains [SEP], and Southern Coastal Plain 

[SCOP]). See appendix 3 for definitions of land-use/land-cover classifications.

Ecoregion Description 

The Mississippi Alluvial Plain 

Ecoregion mainly lies in a flat 

alluvial floodplain that follows the 

Mississippi River south, from southern 

Illinois through parts of Missouri, 

Arkansas, Tennessee, Mississippi, 

and Louisiana, ending at the Gulf of 

Mexico; the ecoregion also includes 

the Red River valley, a finger of land 

that extends from the confluence 

of the Red and Mississippi Rivers 

northwest to Shreveport, Louisiana, 

and beyond, into the southwest 

corner of Arkansas (fig. 1) (Omernik, 

1987; Wiken and others, 2011). 

The ecoregion, which covers about 

141,895 km2 (54,786mi2), is bounded 

on the west by the Ozark Highlands, 

Boston Mountains, Arkansas Valley, 

Ouachita Mountains, South Central 

Plains, and Western Gulf Coastal 

Plain Ecoregions; on the north, by the 

Interior River Lowland Ecoregion; and 

on the east by the Mississippi Valley 

Loess Plains, Southeastern Plains, and 

Southern Coastal Plain Ecoregions.

The climate of the Mississippi 

Alluvial Plain Ecoregion is mild in 

the winter and hot in the summer, 

with average temperatures being 

higher in the south than in the 

north; average annual precipitation 94° 89°

93° 92° 91° 90°

37°

36°

35°

34°

33°

32°

31°

30°

29°

Ozark

Highlands

MVLP

Southeastern

Plains

South Central

Plains

IRL

Arkansas Valley

Boston Mountains

Ouachita

Moutains

IP

SCOP

SCOP

SEP

WGCP

GULF of MEXICO

0 50 100 150 MILES

0 50 100 150 KILOMETERS

Ecoregion boundary

Sample block (10 x 10 km)

Land-use/land-cover class

Water

Developed

Transitional

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Ice/Snow

EXPLANATION

GULF of MEXICO

ARKANSAS

MISSISSIPPI

MISSOURI

IL

TN

TX

KY

Malden

Shreveport

New Orleans

Baton Rouge

Memphis

Plaquemines

Parish

Greenwood

LEFLORE

COUNTY

CRITTENDEN

COUNTY

Indianola

M i s s i s s i p p i R i v e r

R e d R i v e r

LOUISIANA
162 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

also increases from north to south, ranging from 1,100 

to 1,550 mm (43–61 in.). Historically, the ecoregion was 

covered by bottomland deciduous forests, but the expansion 

of farming into the ecoregion between the early 1800s and 

1935 resulted in about half of the forested lands being lost 

(Stanturf, 2006). Rapid tree clearing renewed in the 1940s 

and continued into the early 1970s (McWilliams and Rosson, 

1990, p. 491), allowing agriculture to fully occupy most of 

the ecoregion. The northern and central parts of the ecoregion 

now (2014) are highly cultivated; soybeans, rice, and cotton 

are the leading agricultural products (fig.2). Aquaculture 

also is important, channel catfish (Ictalurus punctatus) being 

the leading commodity. Cotton production has recovered 

from low prices and boll weevil (Anthonomus grandis) 

infestations in the 1970s (Firestone, 2001). The southern 

part of the ecoregion, which is a forested-wetland alluvial 

plain (fig. 3), includes the cities of New Orleans and Baton

Rouge, Louisiana. The mostly deciduous bottomland forests 

are composed of the following four main species groups: (1) 

sugarberry–American elm–green ash (Celtis laevigata, Ulmus 

americana, and Fraxinus pennsylvanica, respectively), 

(2) sweetgum–Nutall’s oak–willow oak (Liquidambar 

styraciflua, Quercus texana, and Quercus phellos, 

respectively), (3) bald cypress–water tupelo (Taxodium 

distichum and Nyssa aquatica, respectively), and (4) overcup 

oak–water hickory (Quercus lyrata and Carya aquatica, 

respectively) (McWilliams and Rosson, 1990, p. 493).

Contemporary Land-Cover Change

(1973 to 2000)

The overall spatial change (the percentage of land area 

that changed at least one time) in the Mississippi Alluvial 

Plain Ecoregion between 1973 and 2000 is estimated at 9.4 

percent (table 1). Compared to other Midwest–South Central 

Figure 2. Examples of agricultural land in Mississippi Alluvial

Plain Ecoregion, including (A) soybean field near Malden, 

Missouri; (B) rice field in Crittenden County, Arkansas, northwest 

of Memphis, Tennessee; and (C) cotton field northeast of 

Indianola, Mississippi. 

Figure 3. Examples of forested wetland alluvial plain in southern 

part of Mississippi Alluvial Plain Ecoregion, including (A) cypress 

swamp in Leflore County, Mississippi, near Greenwood, Mississippi, 

and (B) coastal wetland marsh in Plaquemines Parish, Louisiana. 

A

A B

B

C
Chapter 16—Mississippi Alluvial Plain Ecoregion 163

Figure 4. Overall spatial change in Mississippi Alluvial Plain 

Ecoregion (MAP; darker bars) compared with that of all 17 

Midwest–South Central United States ecoregions (lighter bars). 

Each horizontal set of bars shows proportions of ecoregion that 

changed during one, two, three, or four time periods; highest level 

of spatial change in Mississippi Alluvial Plain Ecoregion (four time 

periods) labeled for clarity. See table 2 for years covered by each 

time period. See appendix 2 for key to ecoregion abbreviations.

Figure 5. Estimates of land-cover change per time period, 

normalized to annual rates of change for all 17 Midwest–South 

Central United States ecoregions (gray bars). Estimates of change 

for Mississippi Alluvial Plain Ecoregion are represented by red 

bars in each time period.

Figure 6. Normalized average net change in Mississippi Alluvial 

Plain Ecoregion by time period for each land-cover class. Bars 

above zero axis represent net gain, whereas bars below zero 

represent net loss. Note that not all land-cover classes shown 

in explanation may be represented in figure. See appendix 3 for 

definitions of land-use and land-cover classifications.

0.5

0.0

1.0

1.5

2.5

3.0

2.0

3.5

1973 to 1980 1980 to 1986 1986 to 1992 1992 to 2000

Average annual change, as percent of ecoregion

Time period

−2

−1

0

1

2

1973–1980 1980–1986 

Time period

1986–1992 1992–2000 

Area changed, as percent of ecoregion 

Water

Developed

Mechanically disturbed

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Nonmechanically disturbed

Ice/Snow

EXPLANATION

LAND-USE/LAND-COVER CLASS

0 12 24 36

Area, as percent of ecoregion

Ecoregion 

DA

HELP

CCBP

SMNIDP

NCHF

BM

IRL

SEWTP

OH

EDP

ECBP

NMW

AV

MAP

NLF

SCP

OM

EXPLANATION

Change in one time period

Change in two time periods

Change in three time periods

Change in four time periods

Change in four time periods

United States ecoregions, change in the Mississippi Alluvial 

Plain Ecoregion was mixed. The change was higher than in the 

Boston Mountains, Interior River Lowland, Ozark Highlands, 

and Arkansas Valley Ecoregions, but it was lower than in the 

Western Gulf Coastal Plain, Mississippi Valley Loess Plains, 

and the South Central Plains Ecoregions (fig. 4): an estimated 

7.4 percent of the area changed only once during the study 

period (table 1). The amount of change per time period varied 

throughout the study, ranging from a low of 2.7 percent to a 

high of 3.6 percent (table 2). When normalized to an average 

annual rate to account for uneven time periods, the period 

between 1973 and 1980 had the greatest amount of change, 

with a rate of 0.5 percent (721 km2) per year (table 2; fig. 5).

In 2000, land-cover classes in the Mississippi Alluvial 

Plain Ecoregion included an estimated 48.7 percent agriculture, 

19.4 percent wetland, 16.3 percent water, and 9.6 percent forest, 

but it was the wetland, water, forest, and developed classes that 

changed the most during the entire 27-year study period (table 

3). The leading land-cover conversion in all time periods was 

the loss of 4,367 km2 of wetland to water between 1973 and 

2000 (table 4). Overall, wetland decreased by about 10.8percent

(3,344 km2), largely a result of coastal wetlands lost to water, 

which increased by 19.0 percent (3,698 km2) (table 3; fig. 6). 

The coastal wetlands in the Mississippi Alluvial Plain Ecoregion 

have been affected greatly by sediment erosion and land 

subsidence (Morton and others, 2003). 

Another substantial amount of change was in the 

developed land-cover class (fig. 7), which increased by 
164 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

37.7percent (1,968 km2) to 5.1 percent of the ecoregion, 

largely through conversion from agriculture and forest 

(table3). Although, when compared to changes in wetland, 

water, and forest, conversions to developed did not account 

for as much change, they still played a substantial role in 

the ecoregion, and they are representative of the growth that 

occurred around the edges of major cities. Timber harvesting 

(classified as conversion from forest to mechanically 

disturbed) was the next most common land-cover conversion 

in the ecoregion (table 4). A 9.7 percent (1,465 km2) 

decrease in forest was caused by increased harvest of upland 

New home construction west of New Orleans, Louisiana. Figure 8. Forest harvesting along Red River valley, Louisiana.

forests, primarily in the Red River valley of Louisiana and 

southwestern Arkansas (fig. 8; table 3).

The loss of coastal wetlands owing to storm damage, 

sediment erosion, and land subsidence was the major driver of 

land-cover change in the Mississippi Alluvial Plain Ecoregion. 

The small decrease in forest because of timber harvesting in 

the Red River valley accounted for much of the remaining 

change. A small but steady increase in the developed landcover class around major cities was due primarily to increasing 

population in the growing metropolitan areas in Louisiana 

between 1970 and 2000 (CensusScope, 2012).
Chapter 16—Mississippi Alluvial Plain Ecoregion 165

Table 2. Raw estimates of change in Mississippi Alluvial Plain Ecoregion land cover, computed for each 

of four time periods between 1973 and 2000, and associated error at 85-percent confidence level.

[Estimates of change per period normalized to annual rate of change for each time period]

Period Total change

(% of ecoregion)

Margin of 

error

(+/− %)

Lower 

bound

(%)

Upper bound

(%)

Standard 

error

(%)

Relative 

error

(%)

Average rate

(% per year)

Estimate of change, in percent stratum

1973–1980 3.6 1.5 2.1 5.0 1.0 27.9 0.5

1980–1986 2.7 0.8 1.8 3.5 0.6 21.0 0.4

1986–1992 2.7 1.0 1.7 3.7 0.7 26.1 0.5

1992–2000 3.1 1.2 1.9 4.3 0.8 26.4 0.4

Estimate of change, in square kilometers

1973–1980 5,046 2,074 2,972 7,120 1,409 28 721

1980–1986 3,763 1,162 2,601 4,926 790 21 627

1986–1992 3,840 1,473 2,367 5,314 1,001 26 640

1992–2000 4,420 1,715 2,704 6,135 1,165 26 552

Table 1. Percentage of Mississippi Alluvial Plain Ecoregion land 

cover that changed at least one time during study period (1973–

2000) and associated statistical error.

[Most sample pixels remained unchanged (90.6 percent), whereas 9.4 percent 

changed at least once throughout study period]

Number

of

changes

Percent

of

ecoregion

Margin

of error

(+/− %)

Lower

bound

(%)

Upper

bound

(%)

Standard

error

(%)

Relative

error

(%)

1 7.4 2.2 5.1 9.6 1.5 20.7

2 1.6 0.7 0.9 2.3 0.5 30.5

3 0.4 0.3 0.1 0.8 0.2 50.7

4 0.1 0.1 0.0 0.1 0.0 61.3

Overall 

spatial 

change

9.4 2.7 6.7 12.1 1.8 19.5
166 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Table 3. Estimated area (and margin of error) of each land-cover class in Mississippi Alluvial Plain Ecoregion, calculated five times 

between 1973 and 2000. See appendix 3 for definitions of land-cover classifications.

Water Developed Mechanically 

disturbed Mining Barren Forest Grassland/Shrubland Agriculture Wetland

Nonmechanically 

disturbed

% +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/−

Area, in percent stratum

1973 13.7 7.2 3.7 1.8 0.1 0.1 0.0 0.0 0.2 0.1 10.6 3.7 0.3 0.2 49.6 7.6 21.8 5.5 0.0 0.0

1980 14.8 7.9 3.9 1.9 0.2 0.2 0.0 0.0 0.1 0.1 10.1 3.5 0.4 0.2 50.0 7.7 20.4 4.8 0.0 0.0

1986 15.5 8.2 4.3 2.0 0.3 0.3 0.0 0.0 0.1 0.1 9.7 3.3 0.5 0.3 49.8 7.7 19.7 4.6 0.0 0.0

1992 16.1 8.2 4.6 2.1 0.4 0.3 0.0 0.0 0.1 0.0 9.6 3.1 0.6 0.4 49.2 7.7 19.5 4.4 0.0 0.0

2000 16.3 8.3 5.1 2.3 0.3 0.2 0.0 0.0 0.1 0.1 9.6 3.2 0.5 0.3 48.7 7.6 19.4 4.4 0.0 0.0

Net

change 2.6 2.1 1.4 0.8 0.2 0.1 0.0 0.0 –0.1 0.1 –1.0 0.7 0.2 0.3 –0.9 0.7 –2.4 2.0 0.0 0.0

Gross

change 3.7 2.1 1.4 0.8 0.9 0.5 0.0 0.0 0.3 0.2 2.0 1.0 1.0 0.5 2.8 0.7 4.0 2.0 0.0 0.0

Area, in square kilometers

1973 19,498 10,205 5,222 2,504 187 132 30 19 254 144 15,042 5,264 439 276 70,342 10,788 30,882 30,882 0 0

1980 21,032 11,183 5,577 2,631 342 282 45 26 212 132 14,327 4,955 576 328 70,877 10,922 28,906 28,906 0 0

1986 21,998 11,663 6,148 2,769 489 419 54 31 179 108 13,716 4,667 768 421 70,643 10,891 27,899 27,899 0 0

1992 22,850 11,692 6,498 2,937 559 470 54 33 97 68 13,553 4,429 801 505 69,770 10,870 27,712 27,712 0 0

2000 23,196 11,841 7,190 3,242 414 287 40 27 142 97 13,577 4,531 738 400 69,060 10,796 27,538 27,538 0 0

Net

change 3,698 2,926 1,968 1,114 227 199 10 25 –112 103 –1,465 1,047 299 423 –1,282 977 –3,344 –3,344 0 0

Gross

change 5,247 2,958 1,983 1,113 1,317 761 66 46 376 214 2,872 1,443 1,396 767 3,983 927 5,643 5,643 0 0
Chapter 16—Mississippi Alluvial Plain Ecoregion 167

Table 4. Principal land-cover conversions in Mississippi Alluvial Plain Ecoregion, showing amount of area changed (and margin of 

error, calculated at 85-percent confidence level) for each conversion during each of four time periods and also during overall study 

period. See appendix 3 for definitions of land-cover classifications.

[Values given for “other” class are combined totals of values for other land-cover classes not listed in that time period. Abbreviations: n/a, not applicable]

Period From class To class

Area 

changed

Margin of 

error

Standard 

error Percent of 

ecoregion

Percent of all 

changes (km2) (+/− km2) (km2)

1973–1980 Wetland Water 1,844 1,854 1,259 1.3 36.5

Wetland Agriculture 725 403 274 0.5 14.4

Water Wetland 419 366 248 0.3 8.3

Forest Agriculture 372 209 142 0.3 7.4

Forest Mechanically disturbed 298 265 180 0.2 5.9

Other Other 1,388 n/a n/a 1.0 27.5

Totals 5,046 3.6 100.0

1980–1986 Wetland Water 1,037 760 517 0.7 27.6

Forest Mechanically disturbed 385 395 268 0.3 10.2

Forest Developed 266 217 147 0.2 7.1

Agriculture Developed 210 174 118 0.1 5.6

Water Wetland 178 134 91 0.1 4.7

Other Other 1,687 n/a n/a 1.2 44.8

Totals 3,763 2.7 100.0

1986–1992 Wetland Water 702 408 277 0.5 18.3

Forest Mechanically disturbed 399 342 232 0.3 10.4

Grassland/Shrubland Forest 286 253 172 0.2 7.5

Mechanically disturbed Grassland/Shrubland 254 318 216 0.2 6.6

Agriculture Water 239 178 121 0.2 6.2

Other Other 1,960 n/a n/a 1.4 51.0

Totals 3,840 2.7 100.0

1992–2000 Wetland Water 784 571 388 0.6 17.7

Water Wetland 499 312 212 0.4 11.3

Mechanically disturbed Forest 408 339 230 0.3 9.2

Grassland/Shrubland Forest 405 410 279 0.3 9.2

Agriculture Developed 355 325 221 0.2 8.0

Other Other 1,970 n/a n/a 1.4 44.6

Totals 4,420 3.1 100.0

1973–2000

(overall)

Wetland Water 4,367 3,057 2,076 3.1 25.6

Forest Mechanically disturbed 1,411 1,115 757 1.0 8.3

Water Wetland 1,272 853 580 0.9 7.5

Wetland Agriculture 1,048 498 339 0.7 6.1

Agriculture Developed 922 690 469 0.6 5.4

Other Other 8,048 n/a n/a 5.7 47.1

Totals 17,069 12.0 100.0
168 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

References Cited

CensusScope, 2012, Louisiana population, 1960–2000: 

CensusScope database, accessed December 17, 2012, at http://

www.censusscope.org/us/s22/chart_popl.html.

Firestone, D., 2001, Farmers return to roots of cotton: New York, 

New York Times, July 16, 2001, accessed April 24, 2014, at 

http://www.nytimes.com/2001/07/16/us/farmers-return-to-rootsof-cotton.html.

McWilliams, W.H., and Rosson, J.F., Jr., 1990, Composition and 

vulnerability of bottomland hardwood forests of the Coastal Plain 

Province in the south central United States: Forest Ecology and 

Management, v. 33–34, p. 485–501.

Morton, R.A., Tiling, G., and Ferina, N.F., 2003, Causes of hotspot wetland loss in the Mississippi delta plain: Environmental 

Geosciences, v. 10, no. 2, p. 71–80.

Omernik, J.M., 1987, Ecoregions of the conterminous United 

States: Annals of the Association of American Geographers, 

v. 77, no. 1, p. 118–125.

Stanturf, J., 2006, Can we bring back Faulkner’s big woods?: 

Compass, no. 6, p. 1–5, accessed September 11, 2014, at 

http://www.srs.fs.usda.gov/compass/issue6/issue6.pdf.

Wiken, E., Jiménez Nava, F., and Griffith, G., 2011, North 

American terrestrial ecoregions—Level III: Montreal, 

Canada, Commission for Environmental Cooperation, 149 

p., accessed November 5, 2012, at http://www.cec.org/

Storage/133/15860_QA07.30-32_NP_NA_Terrestrial_

Ecoregions_Level_3_Final-2june11.pdf.
Chapter 17

Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000 

Edited by Roger F. Auch and Krista A. Karstensen 

U.S. Geological Survey Professional Paper 1794–C, 2015

Ouachita

Moutains

AV

Texas

Blackland

Prairies

Western Gulf

Coastal Plain

Mississippi

Alluvial

Plain

East Central

Texas Plains

ECTP

TBP

Central Oklahoma/

Texas Plains

Mississippi

Valley

Loess

Plains

AV

96° 94° 92°

34°

32°

30°

TX

OK AR

LA

MS

South Central

Plains Ecoregion

Ecoregion boundary

Sample block (10 x 10 km)

Land-use/land-cover class

Water

Developed

Transitional

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Ice/Snow

EXPLANATION

0 5025

0 5025 75

MILES

KILOMETERS

Texarkana

Sam Rayburn

Lake Reservoir

Livingston

Toledo Bend

Reservoir

Shreveport

Houston

Lufkin

Baton Rouge

Longview

Tyler

Nacogdoches

Pine Bluff

Dallas

GULF of MEXICO

Red River

TEXAS

LOUISIANA

ARKANSAS

OKLAHOMA

MS

Mississi p pi River

Ecoregion Description 

The South Central Plains Ecoregion lies at 

the western margin of the southern pine-forest 

belt. The ecoregion covers about 155,520 km2 

(60,047 mi2) of southern Arkansas, northern and 

western Louisiana, southeastern Oklahoma, and 

eastern Texas (fig. 1) (Omernik, 1987; Wiken and 

others, 2011). Neighboring ecoregions include 

the Ouachita Mountains Ecoregion to the north; 

the Mississippi Alluvial Plain Ecoregion to the 

east; the Western Gulf Coastal Plain Ecoregion 

to the south; and the East Central Texas Plains, 

Texas Blackland Prairies, and Central Oklahoma/

Texas Plains Ecoregions to the west. Much of the 

South Central Plains Ecoregion lies within the 

broad southern coastal plain, which is underlain 

by marine and fluvial sedimentary rocks. Soils 

are generally acidic, and a significant amount of 

wetlands are present. Annual precipitation ranges 

from about 1,140 to 1,520 mm (45–60 in.), and

the number of annual frost-free days ranges 

South Central Plains Ecoregion

By Mark A. Drummond

Figure 1. Map of South Central Plains Ecoregion

and surrounding ecoregions, showing land-use/landcover classes from 1992 National Land Cover Dataset 

(Vogelmann and others, 2001); note that not all landuse/land-cover classes shown in explanation may be 

depicted on map; note also that, for this “Status and 

Trends of Land Change” study, transitional land-cover 

class was subdivided into mechanically disturbed 

and nonmechanically disturbed classes. Squares 

indicate locations of 10 x 10 km sample blocks 

analyzed in study. Index map shows locations of 

geographic features mentioned in text. Abbreviations 

for Midwest–South Central United States ecoregions 

are listed in appendix 2. Also shown are parts of 

four Great Plains ecoregions (Central Oklahoma/

Texas Plains, East Central Texas Plains [ECTP], Texas 

Blackland Prairies [TBP], and Western Gulf Coastal 

Plain) and one Eastern United States ecoregion 

(Mississippi Valley Loess Plains). See appendix 3 for 

definitions of land-use/land-cover classifications.
170 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

from 200 days in the north to 300 days in the south (Wiken 

and others, 2011). Climate variability affects the ecoregion in 

the form of periodic droughts, as well as deluges from tropical 

storms and hurricanes.

The South Central Plains Ecoregion is characterized, in 

part, by extensive forest cover; however, much native upland 

pine and hardwood in the ecoregion has been replaced by 

even-aged loblolly pine (Pinus taeda) and shortleaf pine 

(Pinus echinata) plantations (fig. 2). Bottomland forests 

are typified by deciduous species, which include water oak 

(Quercus nigra), willow oak (Quercus phellos), swamp 

chestnut oak (Quercus michauxii), sweetgum (Liquidambar 

styraciflua), blackgum (Nyssa sylvatica), red maple (Acer 

rubrum), bald cypress (Taxodium distichum), and water tupelo 

(Nyssa aquatica) (Wiken and others, 2011). Pasturelands and 

other agricultural lands have been carved out of the upland 

forests, particularly in the western part of the ecoregion (fig. 

3). The valley of the Red River, which divides the ecoregion 

as it runs towards the Mississippi River, supports most of the 

cropland, although much of the Red River valley is included 

in the neighboring Mississippi Alluvial Plain Ecoregion (U.S. 

Environmental Protection Agency, 1999). Streams are common 

in the ecoregion, and several large reservoirs are in its western 

half. The ecoregion generally has no large cities, although 

the Houston, Texas, suburbs extend into its southwest corner. 

Other cities and towns include the Shreveport, Louisiana, 

metropolitan area; Texarkana and Pine Bluff, Arkansas; and 

Longview, Tyler, Nacogdoches, and Lufkin, Texas. Total 

population of the ecoregion increased by about 42 percent, 

from 2.2 million in 1970 to 3.1 million in 2000 (U.S. Census 

Bureau, 1973, 2013).

The patterns of land-cover change in the South Central 

Plains Ecoregion are founded by the biological and geological 

resources of the ecoregion, which include upland forests, 

bottomland forested wetlands, and oil and gas deposits. The 

upland areas support timber production (for lumber and 

pulpwood) and agricultural uses that include pasture and 

confined-poultry operations, as well as oil and gas production 

(Daigle and others, 2004). Upland forest areas in the northern 

part of the ecoregion, which historically have contained a mix 

of shortleaf and loblolly pine and other native trees, generally 

have been replaced by commercially operated pine plantations 

and pasturelands. Upland forest areas in the south half of the 

ecoregion historically included the westernmost range of the 

longleaf pine (Pinus palustris), which, by the end of the 20th 

century, was present in less than 5 percent of its original range 

in the southeastern United States (Earley, 2004). Oil and naturalgas production generally peaked in the early 1970s; however, 

since about 2000, areas in the central part of the ecoregion 

Figure 2. Two areas of even-aged, planted pine in South Central 

Plains Ecoregion. A, Pastureland converted to tree farm. B, Young 

pines (foreground) and mature pine stand (background). 

Figure 3. Two areas of agricultural land in South Central Plains 

Ecoregion. A, Pastureland in rolling uplands of western part of 

ecoregion. B, Confined animal-feeding operations (mostly poultry). 

A

A

B

B
Chapter 17— South Central Plains Ecoregion 171

Contemporary Land-Cover Change 

(1973 to 2000)

Changes in the extent of land cover in the South Central 

Plains Ecoregion are related to several land-conversion 

processes, some of which include cycles of forest harvest 

and regrowth, as well as conversions from agriculture to 

grassland/shrubland and forest, in addition to urbanization 

and mining. The overall spatial change (the percentage of land 

area that changed at least one time) in the South Central Plains 

Ecoregion between 1973 and 2000 is estimated at 27.1 percent 

(table 1). The South Central Plains Ecoregion had the second 

highest overall spatial change of the 17 Midwest–South 

Central United States ecoregions (fig. 4), and it had the third 

highest overall spatial change of all 84 Level III ecoregions of 

the conterminous United States (see appendix 1; see also, U.S. 

Environmental Protection Agency, 1999). A substantial area of 

the ecoregion changed multiple times during the study period: 

the total amount of land area that changed multiple times (15.8 

percent) was larger than the amount of area that changed only 

once (11.3 percent) (table 1), which indicates the cyclic nature 

0.5

0.0

1.0

1.5

2.5

3.0

2.0

3.5

1973 to 1980 1980 to 1986 1986 to 1992 1992 to 2000

Average annual change, as percent of ecoregion

Time period

0 12 24 36

Area, as percent of ecoregion

Ecoregion 

DA

HELP

CCBP

SMNIDP

NCHF

BM

IRL

SEWTP

OH

EDP

ECBP

NMW

AV

MAP

NLF

SCP

OM

EXPLANATION

Change in one time period

Change in two time periods

Change in three time periods

Change in four time periods

Change in four

time periods

−4

−2

0

2

4

1973–1980 1980–1986 

Time period

1986–1992 1992–2000 

Area changed, as percent of ecoregion 

Water

Developed

Mechanically disturbed

Mining

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Nonmechanically disturbed

Ice/Snow

EXPLANATION

LAND-USE/LAND-COVER CLASS

(northwestern Louisiana, southwestern Arkansas, and eastern 

Texas), where the Haynesville shale-gas formation is located, 

have experienced an increase in drilling activity and well-pad 

construction (U.S. Bureau of Land Management, 2008).

Figure 4. Overall spatial change in South Central Plains 

Ecoregion (SCP; darker bars) compared with that of all 17 

Midwest–South Central United States ecoregions (lighter bars). 

Each horizontal set of bars shows proportions of ecoregion that 

changed during one, two, three, or four time periods; highest 

level of spatial change in South Central Plains (four time periods) 

labeled for clarity. See table 2 for years covered by each time 

period. See appendix 2 for key to ecoregion abbreviations.

Figure 5. Estimates of land-cover change per time period, 

normalized to annual rates of change for all 17 Midwest–South 

Central United States ecoregions (gray bars). Estimates of change 

for South Central Plains Ecoregion are represented by red bars in 

each time period.

Figure 6. Normalized average net change in South Central Plains 

Ecoregion by time period for each land-cover class. Bars above 

zero axis represent net gain, whereas bars below zero represent 

net loss. Note that not all land-cover classes shown in explanation 

may be represented in figure. See appendix 3 for definitions of 

land-use and land-cover classifications.
172 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

of land conversion in the fast-growing pine-plantation areas. 

The average annual rate of change increased from 1.1 percent 

between 1973 and 1980, to 1.9 percent between 1980 and 

1986, and to 2.2 percent between 1986 and 1992, declining 

slightly to 1.9 percent between 1992 and 2000 (table 2; fig. 5).

The largest net change in ecoregion area between 1973 and 

2000 occurred in the forest land-cover class, which constituted 

over one-half of the total ecoregion area (an estimated 58.7 

percent in 2000) (table 3). Decreases in forest land affected 

about 4.9 percent (7,579 km2) of the ecoregion between 1973 

and 2000. The four leading land-cover class conversions 

between 1973 and 2000 involved various stages of forest 

harvest (mechanically disturbed to forest) and revegetation 

(mechanically disturbed to forest, mechanically disturbed to 

grassland/shrubland, and grassland/shrubland to forest), with 

substantially less activity between 1973 and 1980 than in the 

subsequent three time periods (table 4). Changes in forest land 

indicate the significance of lumber and pulpwood in the regional 

economy. The change from agriculture to forest, the fifth leading 

land-cover conversion between 1973 and 2000, likely indicates 

a switch from pasture and hay production to silviculture.

The effects of forestry activities are shown by an increase 

in mechanically disturbed land, which increased by 4.4 percent 

of the total ecoregion area between 1973 and 2000 (table 3). 

Mechanically disturbed land increased from an estimated 2.9 

percent (4,563 km2) of the ecoregion in 1973, to an estimated 

7.4 percent (11,480 km2) of the ecoregion in 2000, suggesting 

a general acceleration in the rate of forest cutting. However, 

the rate and timing of tree regrowth caused a variable rate of 

net change in forest land cover, including a period of small net 

forest gain (0.5 percent) between 1986 and 1992 that did not 

reverse the overall trend of forest loss (fig. 6).

Net agricultural land decreases affected nearly 1.0 

percent (1,549 km2) of the ecoregion between 1973 and 

2000. Agriculture, which was the second most extensive 

land-cover class, constituted about 18.2 percent of the 

ecoregion area in 2000 (table 3). Forest was lost to agriculture 

between 1973 and 1980, but thereafter forest gained from 

agriculture (table 4). This change after 1980 likely was 

due to the conversion of agricultural land to planted-pine 

plantations as the profitability of timber production increased. 

Conversion of agriculture to grassland/shrubland—possibly 

as an intermediate stage in the change to forest land—also 

occurred, but it was not one of the top conversions (it was 

included as part of the “Other” change class in table 4). 

Agriculture also lost to developed (301 km2), water (92 km2), 

and mining (20 km2) (these also were included as part of the 

“Other” change class, in the “1973–2000 (overall)” section of 

table 4). However, most of the expansion to mining occurred 

on forest land (590 km2, included as part of the “Other” 

change class in the “1973–2000 (overall)” section of table 4), 

and at least some of the increase in mining that occurred after 

1986 is related to surface mining of small fields of lignite coal 

deposits in the central part of the ecoregion. A small part of 

the mining land-cover class includes the total area of forest 

land converted to gas- and oil-well pads (fig. 7A).

Figure 7. Mining and developed land-cover classes in South 

Central Plains Ecoregion. A, Natural-gas well pad. B, Land recently 

cleared for development. 

Developed land increased by 53.3 percent between 1973 and 

2000, from 1.7 percent of the ecoregion in 1973 to 2.6 percent 

of the ecoregion in 2000 (fig. 7B; table 3). The conversion 

occurred mostly at the expense of forest (an estimated 1,011 km2) 

compared to agriculture (301 km2) (both of these conversions are 

included as part of the “Other” change class in the “1973–2000 

(overall)” section of table 4). The analysis showed only a small 

decrease in wetlands, which affected 0.2 percent of the ecoregion 

(table 3). The area of surface water increased by 0.2 percent as 

a result of reservoir construction on forest land and agricultural 

land (table 3). No natural disturbance (nonmechanically disturbed 

land-cover class) was detected.

Pine-plantation forestry was a major driver of land change 

in the ecoregion. Tree cutting-and-regrowth cycles accounted 

for much of the land-cover-class conversions between 1973 

and 2000, as well as for the large footprint of overall spatial 

change. Additionally, the changes from agriculture to forest 

were driven by the economic opportunities associated with 

converting marginal farmland to plantation forestry. Despite 

some conversion from agriculture to forest, the expansion 

of mechanical disturbance, land development, and mining 

caused an overall net decrease in forest land cover. Increased 

demands on the ecoregion in the future could cause an 

accelerated conversion of natural and seminatural hardwood 

forest environments to planted-pine environments, which may 

have undesirable consequences for biomass carbon stocks and 

ecosystem services (Sohngen and Brown, 2006). 

A

B
Chapter 17— South Central Plains Ecoregion 173

Table 1. Percentage of South Central Plains Ecoregion land 

cover that changed at least one time during study period (1973–

2000) and associated statistical error. 

[Most sample pixels remained unchanged (72.9 percent), whereas 

27.1 percent changed at least once throughout study period]

Number

of

changes

Percent

of

ecoregion

Margin

of error

(+/− %)

Lower

bound

(%)

Upper

bound

(%)

Standard

error

(%)

Relative

error

(%)

1 11.3 1.3 10.0 12.6 0.9 8.0

2 11.8 1.9 10.0 13.7 1.3 10.6

3 3.6 1.0 2.6 4.6 0.7 18.6

4 0.4 0.2 0.2 0.6 0.1 36.5

Overall 

spatial 

change

27.1 3.4 23.7 30.5 2.3 8.5

Table 2. Raw estimates of change in South Central Plains Ecoregion land cover, 

computed for each of four time periods between 1973 and 2000, and associated error 

at 85-percent confidence level.

[Estimates of change per period normalized to annual rate of change for each time period]

Period

Total change

(% of

ecoregion)

Margin

of error

(+/− %)

Lower 

bound

(%)

Upper 

bound

(%)

Standard 

error

(%)

Relative 

error

(%)

Average 

rate

(% per year)

Estimate of change, in percent stratum

1973–1980 7.6 1.6 5.9 9.2 1.1 14.7 1.1

1980–1986 11.4 1.8 9.5 13.2 1.2 10.9 1.9

1986–1992 13.0 2.0 11.0 15.0 1.4 10.5 2.2

1992–2000 15.4 2.3 13.1 17.7 1.6 10.1 1.9

Estimate of change, in square kilometers

1973–1980 11,786 2,554 9,231 14,340 1,735 14.7 1,684

1980–1986 17,667 2,837 14,830 20,504 1,927 10.9 2,944

1986–1992 20,262 3,117 17,145 23,379 2,118 10.5 3,377

1992–2000 23,913 3,556 20,358 27,469 2,416 10.1 2,989
174 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Table 3. Estimated area (and margin of error) of each land-cover class in South Central Plains Ecoregion, calculated five times 

between 1973 and 2000. See appendix 3 for definitions of land-cover classifications.

Water Developed Mechanically 

disturbed Mining Barren Forest Grassland/Shrubland Agriculture Wetland

Nonmechanically 

disturbed

% +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/− % +/−

Area, in percent stratum

1973 3.7 2.8 1.7 0.6 2.9 0.9 0.1 0.1 0.0 0.0 63.6 4.3 0.8 0.3 19.1 4.4 8.1 1.8 0.0 0.0

1980 3.8 2.9 1.8 0.6 4.0 1.1 0.1 0.1 0.0 0.0 61.9 4.1 1.1 0.3 19.2 4.4 8.1 1.8 0.0 0.0

1986 3.8 2.9 2.2 0.7 5.8 1.2 0.1 0.1 0.0 0.0 59.4 4.2 1.7 0.6 19.0 4.4 8.0 1.8 0.0 0.0

1992 3.9 2.9 2.3 0.7 5.1 1.1 0.2 0.1 0.0 0.0 59.9 4.0 2.0 0.5 18.5 4.3 8.0 1.8 0.0 0.0

2000 3.9 2.9 2.6 0.8 7.4 1.4 0.4 0.3 0.0 0.0 58.7 3.8 1.0 0.3 18.2 4.3 7.9 1.8 0.0 0.0

Net

change 0.2 0.1 0.9 0.4 4.4 1.4 0.3 0.3 0.0 0.0 –4.9 1.5 0.2 0.3 –1.0 0.4 –0.2 0.2 0.0 0.0

Gross

change 0.4 0.3 0.9 0.4 13.8 2.5 0.4 0.3 0.0 0.0 14.3 2.5 4.2 1.3 1.9 0.4 0.7 0.3 0.1 0.1

Area, in square kilometers

1973 5,725 4,414 2,598 894 4,563 1,416 116 84 18 20 98,914 6,683 1,191 450 29,728 6,839 12,666 2,829 0 0

1980 5,883 4,480 2,829 965 6,298 1,762 148 113 19 20 96,214 6,437 1,667 418 29,865 6,843 12,598 2,827 0 0

1986 5,929 4,464 3,356 1,070 8,963 1,871 194 90 19 20 92,387 6,477 2,627 869 29,530 6,819 12,515 2,811 0 0

1992 6,083 4,467 3,557 1,108 8,000 1,716 300 140 19 20 93,147 6,252 3,055 817 28,834 6,760 12,479 2,807 46 67

2000 6,007 4,448 3,983 1,224 11,480 2,168 648 445 20 20 91,336 5,929 1,481 394 28,249 6,718 12,315 2,764 0 0

Net

change 282 125 1,385 580 6,917 2,115 532 443 2 2 –7,579 2,309 291 518 –1,479 686 –351 337 0 0

Gross

change 632 422 1,388 581 21,432 3,875 634 444 2 2 22,274 3,934 6,479 1,980 2,879 652 1,082 506 93 135
Chapter 17— South Central Plains Ecoregion 175

Table 4. Principal land-cover conversions in South Central Plains Ecoregion, showing amount of area changed (and margin of error, 

calculated at 85-percent confidence level) for each conversion during each of four time periods and also during overall study period. 

See appendix 3 for definitions of land-cover classifications.

[Values given for “other” classes are combined totals of values for other land-cover classes not listed in that time period. Abbreviations: n/a, not applicable]

Period From class To class

Area 

changed

Margin of 

error

Standard 

error Percent of 

ecoregion

Percent of all 

changes (km2) (+/− km2) (km2)

1973–1980 Forest Mechanically disturbed 5,917 1,721 1,169 3.8 50.2

Mechanically disturbed Forest 3,292 1,265 860 2.1 27.9

Mechanically disturbed Grassland/Shrubland 804 278 189 0.5 6.8

Forest Agriculture 437 145 99 0.3 3.7

Grassland/Shrubland Forest 362 327 222 0.2 3.1

Other Other 974 n/a n/a 0.6 8.3

Totals 11,786 7.6 100.0

1980–1986 Forest Mechanically disturbed 8,554 1,817 1,234 5.5 48.4

Mechanically disturbed Forest 4,496 1,496 1,016 2.9 25.4

Mechanically disturbed Grassland/Shrubland 1,492 840 571 1.0 8.4

Grassland/Shrubland Forest 787 240 163 0.5 4.5

Agriculture Forest 419 205 140 0.3 2.4

Other Other 1,918 n/a n/a 1.2 10.9

Totals 17,667 11.4 100.0

1986–1992 Forest Mechanically disturbed 7,649 1,675 1,138 4.9 37.7

Mechanically disturbed Forest 6,717 1,558 1,059 4.3 33.2

Grassland/Shrubland Forest 1,792 826 561 1.2 8.8

Mechanically disturbed Grassland/Shrubland 1,751 690 468 1.1 8.6

Agriculture Forest 538 188 128 0.3 2.7

Other Other 1,815 n/a n/a 1.2 9.0

Totals 20,262 13.0 100.0

1992–2000 Forest Mechanically disturbed 10,866 2,166 1,471 7.0 45.4

Mechanically disturbed Forest 7,232 1,601 1,088 4.7 30.2

Grassland/Shrubland Forest 2,260 787 535 1.5 9.5

Agriculture Forest 718 253 172 0.5 3.0

Mechanically disturbed Grassland/Shrubland 444 183 124 0.3 1.9

Other Other 2,394 n/a n/a 1.5 10.0

Totals 23,913 15.4 100.0

1973–2000

(overall)

Forest Mechanically disturbed 32,986 5,862 3,982 21.2 44.8

Mechanically disturbed Forest 21,737 4,729 3,213 14.0 29.5

Grassland/Shrubland Forest 5,201 1,390 944 3.3 7.1

Mechanically disturbed Grassland/Shrubland 4,491 1,294 879 2.9 6.1

Agriculture Forest 1,895 550 373 1.2 2.6

Forest Agriculture 1,358 375 254 0.9 1.8

Other Other 5,960 n/a n/a 3.8 8.1

Totals 73,628 47.3 100.0
176 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

References Cited

Daigle, J.J., Griffith, G.E., Omernik, J.M., Faulkner, 

P.L., McCulloh, R.P., Handley, L.R., Smith, L.M., 

and Chapman, S.S., 2004, Ecoregions of Louisiana: 

U.S. Geological Survey Ecoregion Map Series, scale 

1:1,000,000, available at http://www.epa.gov/wed/pages/

ecoregions/la_eco.htm.

Earley, L.S., 2004, Looking for longleaf—The fall and rise 

of an American forest: Chapel Hill, University of North 

Carolina Press, 322 p.

Omernik, J.M., 1987, Ecoregions of the conterminous 

United States: Annals of the Association of American 

Geographers, v. 77, no. 1, p. 118–125.

Sohngen, B., and Brown, S., 2006, The influence of 

conversion of forest types on carbon sequestration and 

other ecosystem services in the south central United 

States: Ecological Economics, v. 57, p. 698–708.

U.S. Bureau of Land Management, 2008, Louisiana—

Reasonably foreseeable development scenario for fluid 

minerals: Bureau of Land Management, Eastern States 

Jackson Field Office Report R2, accessed March 11, 

2013, at http://www.blm.gov/pgdata/etc/medialib/blm/

es/jackson_field_office/planning/plannng_pdf_ar_rfds.

Par.96360.File.dat/LA_RFDS_R2.pdf.

U.S. Census Bureau, 1973, Census of population and housing, 

1970—Vol. 1, Characteristics of the population: U.S. Census 

Bureau database, accessed at http://www.census.gov/prod/

www/decennial.html.

U.S. Census Bureau, 2013, State and county quick facts—

Census 2000 Summary File 1 (SF 1) 100-Percent Data 

database: U.S. Census Bureau database, accessed March 11, 

2013, at http://quickfacts.census.gov/qfd/index.html.

U.S. Environmental Protection Agency, 1999, LevelIII ecoregions

of the continental United States: U.S. Environmental Protection 

Agency National Health and Environmental Effects Research 

Laboratory, scale 1:7,500,000, available at ftp://ftp.epa.gov/wed/

ecoregions/usgs/useco_March1999_v5.pdf. 

Vogelmann, J.E., Howard, S.M., Yang, L., Larson, C.R., Wylie, 

B.K., and van Driel, N., 2001, Completion of the 1990s 

National Land Cover Data Set for the conterminous United 

States from Landsat Thematic Mapper data and ancillary data 

sources: Photogrammetric Engineering & Remote Sensing, v. 

67, p. 650–662.

Wiken, E., Jiménez Nava, F., and Griffith, G., 2011, North American 

terrestrial ecoregions—Level III: Montreal, Canada, Commission 

for Environmental Cooperation, 149 p., accessed February 14, 

2013, at http://www.cec.org/Storage/133/15860_QA07.30-32_

NP_NA_Terrestrial_Ecoregions_Level_3_Final-2june11.pdf.
Appendixes 1–4

Appendix 1. Map of Ecoregions in Conterminous United States 179

This volume—U.S. Geological Survey Professional Paper 1794–C, which covers 17 ecoregions in the Midwest–South Central 

United States—provides an assessment of the rates and causes of land-use and land-cover change in the Midwest–South Central United 

States region between 1973 and 2000. The other three volumes of this Professional Paper (1794–A, 1794–B, and 1794–D) provide 

similar analyses for the Western United States, the Great Plains of the United States, and the Eastern United States regions, respectively.

The map contained in this appendix (fig. 1.1) shows all 84 ecoregions in the conterminous United States, as originally defined by 

Omernik (1987) and later modified by the U.S. Environmental Protection Agency (1997), in addition to the ecoregions that are contained 

in the Western United States, Great Plains of the United States, Midwest–South Central United States, and Eastern United States regions. 

Also shown are the land-use/land-cover classes from the 2001 National Land-Cover Database (Homer and others, 2004). 

References Cited

Homer, C., Huang, C., Yang, L., Wylie, B., and Coan, M., 2004, Development of a 2001 National Land-Cover Database for the 

United States: Photogrammetric Engineering and Remote Sensing, v. 70, no. 7, p. 829–840.

Omernik, J.M., 1987, Ecoregions of the conterminous United States: Annals of the Association of American Geographers, v. 77, 

no. 1, p. 118–125.

U.S. Environmental Protection Agency, 1997, Descriptions of level III ecological regions for the CEC report on ecological 

regions of North America: U.S. Environmental Protection Agency database, accessed April 12, 2006, at http://www.epa.gov/

wed/pages/ecoregions/na_eco.htm#Downloads.

Ecoregion Abbreviations Used on Map

[Map is on following pages]

ACPB Atlantic Coastal Pine Barrens Ecoregion

ANMM Arizona/New Mexico Mountains Ecoregion

CR Coast Range Ecoregion

CRK Canadian Rockies Ecoregion

EGLHL Eastern Great Lakes and Hudson Lowlands Ecoregion

HELP Huron/Erie Lake Plains Ecoregion

LPH Laurentian Plains and Hills Ecoregion

MACP Middle Atlantic Coastal Plain Ecoregion

MRK Middle Rockies Ecoregion

MVFP Montana Valley and Foothill Prairies Ecoregion

MVLP Mississippi Valley Loess Plains Ecoregion

NAPU Northern Appalachian Plateau and Uplands Ecoregion

NCA North Central Appalachians Ecoregion

NCHF North Central Hardwood Forests Ecoregion

NECZ Northeastern Coastal Zone Ecoregion

NEH Northeastern Highlands Ecoregion

NLF Northern Lakes and Forests Ecoregion

NMW Northern Minnesota Wetlands Ecoregion

PL Puget Lowland Ecoregion

SCCCOW Southern and Central California Chaparral and Oak Woodlands Ecoregion

SCM Southern California Mountains Ecoregion

SEWTP Southeastern Wisconsin Till Plains Ecoregion

SFCP Southern Florida Coastal Plain Ecoregion

TBP Texas Blackland Prairies Ecoregion

WUM Wasatch and Uinta Mountains Ecoregion

WV Willamette Valley Ecoregion

Appendix 1. Map of Ecoregions in Conterminous United States
180 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

100°

100°

110°

120° 110°

120°

50°

40°

30°

MEXICO

PA C I F I C

OCEAN

WV

PL

BLM

ECSF

CRK

WUM

Blue Mountains

Central Basin

and Range

Central California Valley

Columbia Plateau

Colorado

Plateaus

Coast Range

Cascades

Klamath

Mountains

Madrean

Archipelago

Mojave Basin

and Range

Middle

Rockies

MVFP

Northern Basin

and Range

Northern

Rockies

PL

Sonoran Basin

and Range

SCCCOW

SCCCOW

SCM

Sierra Nevada

Snake River Basin

Southern

Rockies

Wyoming Basin

SCCCOW

CR

MRK

ANMM

Central 

Pla

E

Edwards

Plateau

Nebraska Sand Hills

Northwestern Great Plains

Southern

Texas Plains

Western

High Plains

Western

High Plains

North

Cascades

Chihuahuan Deserts

Northwestern Glaciated Plains

Southwestern

Tablelands

Ce

Oklaho

P

Eastern

Cascades

Slopes and

Foothills

MRK

0 125 250 500 MILES

0 125 250 500 KILOMETERS

Arizona/

New Mexico

Plateau

Arizona/ 

 New Mexico

 Mountains

WESTERN UNITED STATES

GREAT P

Figure 1.1. Map 

of ecoregions in 

conterminous 

United States.
Appendix 1. Map of Ecoregions in Conterminous United States 181

70°

70°

50°

80°

80°

90°

90°

40°

30°

CANADA

ATLANTIC

OCEAN

Gulf

of 

Mexico

HELP

NCHF

NMW

SEWTP

NLF

NECZ

NAPU

NCA

SFCP

NEH

SFCP

Southern

Coastal

Plain

Western

Allegheny

Plateau

Appalachians

Southwestern

Southeastern Plains

Northeastern

Highlands

Middle Atlantic Coastal Plain

Interior

Plateau

Blue Ridge Mountains

Ridge and Valley

Northern Piedmont

ACPB

MACP

MACP

LPH

NEH

NEH

EGLHL

NCA

l Great

ins

East Central Texas Plains

Western Gulf Coastal Plain

TBP

Lake

Agassiz

Plain

Northern

Glaciated Plains

s

Western Corn Belt Plains

Central

Irregular

Plains

Boston Mountains

Central Corn

Belt Plains Eastern Corn

Belt Plains

Erie Drift Plains

HELP

Interior

River Lowland

Northern Lakes

and Forests

Ozark Highlands

South

Central

Plains

Southern 

Michigan/

Northern 

Indiana 

Drift Plains 

Flint

Hills

Ouachita Mountains

Arkansas Valley

entral

oma/Texas

lains

TBP

MVLP

Mississippi

Alluvial

Plain

Driftless

Area

 Central

Appalachians

Piedmont

EXPLANATION

Water

Developed

Barren

Forest

Grassland/Shrubland

Agriculture

Wetland

Ice/Snow

Land-use/land-cover class

PLAINS

 MIDWEST–

SOUTH CENTRAL

UNITED STATES

EASTERN UNITED STATES

Ecoregion boundary

Major ecoregion group boundary
182 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

AV Arkansas Valley Ecoregion

BM Boston Mountains Ecoregion

CCBP Central Corn Belt Plains Ecoregion

DA Driftless Area Ecoregion

ECBP Eastern Corn Belt Plains Ecoregion

EDP Erie Drift Plains Ecoregion

HELP Huron/Erie Lake Plains Ecoregion

IRL Interior River Lowland Ecoregion

MAP Mississippi Alluvial Plain Ecoregion

NCHF North Central Hardwood Forests Ecoregion

NLF Northern Lakes and Forests Ecoregion

NMW Northern Minnesota Wetlands Ecoregion

OH Ozark Highlands Ecoregion

OM Ouachita Mountains Ecoregion

SCP South Central Plains Ecoregion

SEWTP Southeastern Wisconsin Till Plains Ecoregion

SMNIDP Southern Michigan/Northern Indiana Drift Plains Ecoregion

Appendix 2. Abbreviations for Ecoregions in the Midwest–South Central

United States
Appendix 3. Land-Cover Classification System Used in “Status and Trends of Land Change” Study 183

Appendix 3. Land-Cover Classification System Used in “Status and Trends of 

Land Change” Study

This analysis of land-use/land-cover change during the 

1973–2000 study period is based on land-cover classifications 

mapped for five study dates—1973, 1980, 1986, 1992, and 

2000. The use of moderate-resolution imagery—Landsat 

Multispectral Scanner, Thematic Mapper, and Enhanced 

Thematic Mapper Plus—necessitated a land-cover 

classification system that was fairly general in order to achieve 

high levels of accuracy and consistency in the interpretations. 

The classification system also needed to contain classes that 

could be used as an appropriate surrogate for land use. This 

classification, which is based on the Anderson Level I classes 

(Anderson and others, 1976), was used because the classes 

have been designed as use surrogates, but this system has 

been further modified by adding two transitional disturbance 

categories, mechanically disturbed (human induced) and 

nonmechanically disturbed (natural). 

The classification system used consists of the following 

11 general land-cover classes: water, developed, mechanically 

disturbed, mining, barren, forest, grassland/shrubland, 

agriculture, wetland, nonmechanically disturbed, and ice/

snow. Classes are defined as follows:

Water—Areas that are persistently covered with water, 

such as perennial streams, canals, rivers, lakes, reservoirs, 

bays, and oceans.

Developed—Areas of intensive use, in which much of 

the land is covered with structures or other anthropogenically 

induced, impermeable surfaces (for example, high-density 

residential, commercial, and industrial areas, as well as 

roads, highways, and other transportation corridors), or less 

intensive use, in which the land-cover matrix includes both 

vegetation and structures (for example, low-density residential 

areas, recreational facilities, cemeteries, parking lots, and 

utility corridors). Land that is functionally related to urban or 

built-up environments (for example, parks and golf courses) is 

also included.

Mechanically disturbed—Land in an altered and 

often unvegetated state owing to disturbance by mechanical 

(that is, human) means. Mechanically disturbed land is in 

transition from one land-cover class to another. Processes 

leading to mechanical disturbance include forest clearcutting, 

earthmoving, scraping, chaining, reservoir drawdown, and 

other types of anthropogenically induced changes.

Mining—Areas of extractive mining activities that have 

significant surface expression, including mining buildings and 

apparatus, quarry pits, evaporation and leach ponds, tailings and 

overburden piles, and other components related to mining, to 

the extent that these features can be detected.

Barren—Areas of bare soil, sand, or rock, in which less 

than 10 percent of the area is vegetated. Barren lands generally 

are naturally occurring.

Forest—Tree-covered land where the tree-cover density 

is greater than 10 percent. Cleared forest land is mapped 

(according to land cover at the time of the imagery) as either 

mechanically disturbed or grassland/shrubland.

Grassland/Shrubland—Land that is predominately 

covered with grasses, forbs, or shrubs. Vegetated cover must 

make up at least 10 percent of the area.

Agriculture—Land, in either a vegetated or an 

unvegetated state, used for the production of food or fiber. 

This includes cultivated and uncultivated croplands, hay lands, 

pasture, orchards, vineyards, and confined-livestock operations. 

However, forest plantations always are classified as forest, 

regardless of how the wood products are used.

Wetland—Land where water saturation is the determining 

factor in soil characteristics, vegetation types, and animal 

communities. Wetlands usually contain both water and 

vegetated cover.

Nonmechanically disturbed—Land in an altered and 

often unvegetated state owing to disturbance by nonmechanical 

(that is, natural) means. Nonmechanically disturbed land is 

in transition from one land-cover class to another. Causes of 

nonmechanical disturbance include fire, wind, floods, animals, 

and other similar phenomena.

Ice/Snow—Land where the accumulation of snow and 

ice does not completely melt during the summer period (for 

example, alpine glaciers and perennial snowfields).

Reference Cited

Anderson, J.R., Hardy, E.E., Roach, J.T., and Witmer, R.E., 

1976, A Land Use and Land Cover Classification System 

for Use with Remote Sensor Data: U.S. Geological Survey 

Professional Paper 964, 28 p., available at http://pubs.usgs.

gov/pp/0964/report.pdf.
184 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Appendix 4. Methodology Used in “Status and Trends of Land Change” Study

This appendix describes the methodology used to 

document the temporal and spatial rates, trends, and types 

of change documented in this “Status and Trends of Land 

Change” study. The methodology is based on a statistical 

sampling approach, manual classification of land use and 

land cover, and postclassification comparisons of land cover 

over five different study dates (Loveland and others, 2002). 

U.S. Environmental Protection Agency’s (1999) Level III 

ecoregions provided the geographic framework for regional 

land-cover change estimates, and land-use/land-cover change 

was estimated on an ecoregion-by-ecoregion basis using a 

probability sample of randomly selected blocks within each of 

84 ecoregions across the conterminous United States. For each 

sample block, five dates of Landsat imagery were interpreted 

in order to map land use and land cover, using a classification 

system that consists of 11 general land-cover classes (see 

appendix 3, entitled “Land-Cover Classification System Used 

in ‘Status and Trends of Land Change’ Study”). The resulting 

land-cover data for each sample block were used to determine 

change for four time periods, and sample-block data were used 

to calculate change estimates for each ecoregion. 

Sampling Strategy

In this study, a sampling strategy was used as a costefficient method for characterizing land-cover change in an 

area as large as the conterminous United States. The study 

used a stratified random sample of 2,688 square blocks 

(fig. 1); a random sample of these blocks was independently 

selected for each ecoregion analyzed. Because the study used 

a probability sample, the estimates of land-use/land-cover 

change that are derived can be considered as categorically 

representative of the population (Kish, 1987). 

The size of each sample block in this study, as well as 

the sampling density (that is, the number of sample blocks 

analyzed per ecoregion), was based on a compromise between 

two conflicting objectives: (1) estimating change in landcover area, and (2) estimating change in landscape pattern. 

Larger numbers of smaller sample blocks would result in 

more precise estimates of change in land-cover area, whereas 

smaller numbers of larger sample blocks would be more 

desirable for characterizing landscape pattern. 

Size of Samples

In the initial study design, a 20 × 20 km (400 km2) 

sample-block size was used, and nine ecoregions were 

analyzed, each analysis consisting of 9 to 11 sample blocks. 

On the basis of results from these initial ecoregion analyses, 

a decision was made to use a higher density of smaller (10 

× 10 km; 100 km2) sample blocks for the remainder of the 

ecoregion analyses in order to maximize the precision of the 

land-cover change estimates.

Sampling Density

The sampling density was determined by both the project 

requirements for precision in the change estimates and the 

expected characteristics of change within the ecoregion 

being studied. As precision requirements increase, so must 

the sampling density. Similarly, a greater sampling density is 

required when areas of change are expected to be less evenly 

distributed throughout an ecoregion.

In this study, the target precision level was to map gross 

overall change to within a ±1% margin of error at an 85% 

confidence level for each ecoregion. On the basis of this target 

precision level and the expected characteristics of change 

within all 84 ecoregions in the conterminous United States, 

it was determined that between 25 and 48 of the 10 × 10 

km sample blocks per ecoregion would likely be needed to 

adequately characterize overall change in each ecoregion.

Implementation of the Sampling Strategy

The sampling strategy outlined above was fairly 

straightforward to implement. A regular grid of 10 × 10 km 

(or, in a few cases, 20 × 20 km) sample blocks was overlain on 

an ecoregion map of the conterminous United States. Blocks 

whose centers fell within the boundaries of an ecoregion were 

highlighted as potentially valid sample blocks for that ecoregion 

and then were assigned a unique numerical value from 1 to N. 

A random number generator was then used to select sample 

blocks, one at a time, until the desired number was reached. 

Thus, each sample block within an ecoregion had an equal 

probability of being included in the final sample analysis. 

Although the number of sample blocks selected and 

analyzed was based on both the target precision level and 

the expected characteristics of change within the ecoregion, 

unexpected heterogeneity in the distribution of change 

could still result in the estimates of change having levels of 

precision that are lower than desired. Should this occur, the 

sampling strategy allowed for the selection and interpretation 

of additional sample blocks. The inclusion of these reserve 

blocks allowed the analysis to achieve change estimates that 

have acceptable levels of precision. In actuality, for various 

reasons, no reserve blocks were implemented. 

Geographic Framework

A central premise of the study design was the use of a 

geographic framework to provide regional land-cover change 

estimates. Geographers have long used regional frameworks 

because they capture the essence and potential of the 

landscape without masking the roles of environmental, social, 

and economic forces (Turner and Meyer, 1991). This “Status 

and Trends of Land Change” study chose to use ecoregions, 

as originally defined by Omernik (1987) and later modified 
Appendix 4. Methodology Used in “Status and Trends of Land Change” Study 185

by the U.S. Environmental Protection Agency (1999), as the 

framework from which to tell the regional story of change. 

Ecoregions were chosen as the unit of analysis because 

(1) they provide a means to localize estimates of the rates 

and driving forces of change, (2) they were developed by 

synthesizing information on a wide variety of factors (for 

example, climate, geology, physiography, soils, vegetation, 

hydrology, and human influences) and, therefore, should 

reflect both current land-use and land-cover types and future 

change trajectories, and (3) they provide a framework that can 

be extended globally. 

Landsat Data

Landsat satellite imagery was the primary source of 

data used for detecting land-cover change in this study. Data 

from the Landsat Multispectral Scanner (MSS), Thematic 

Mapper (TM), and Enhanced Thematic Mapper Plus (ETM+) 

instruments were acquired from the Landsat data archive: 

Landsat MSS datasets are available from late-1972 through 

late-1992; Landsat TM data are available from 1982 to 2012; 

and Landsat ETM+ data are available from 1999 to the present 

(2015). Each of these products provided a consistent, synoptic, 

multispectral view of the land surface from which land cover 

could be interpreted for the period between 1972 and 2000. To 

analyze trends in land-use/land-cover change throughout this 

period, five target study dates spaced at semiregular intervals 

(1973, 1980, 1986, 1992, and 2000) were selected. Landsat 

imagery corresponding to each 10 × 10 km (or 20 × 20 km) 

sample block was extracted from full Landsat scenes, resulting 

in five dates of satellite imagery for each sample block. To 

reduce expenses, the initial data-acquisition strategy was to 

use existing geoprocessed Landsat datasets as the primary 

input data source. Four of the five dates of Landsat MSS, 

TM, and ETM+ data were available in a geocoded format as 

a result of processing done for two previous projects: (1) the 

North American Landscape Characterization (NALC) project 

produced 1973, 1986, and 1992 geocoded Landsat MSS datasets 

for the conterminous United States and Mexico (Lunetta and 

others, 1998), and (2) the 1992 TM and 2000 ETM+ data 

came from the Multiresolution Landscape Characterization 

initiative (Loveland and Shaw, 1996). New 1980 Landsat MSS 

acquisitions were obtained in order to maintain the six- to eightyear interval between the five target dates. 

The Landsat MSS, TM, and ETM+ scenes obtained 

were previously georeferenced to root-mean-square error of 1 

pixel or less but to differing map projections. For this study, 

all scenes were translated to a common Albers equal-area 

projection. Most of the NALC MSS data had also been terraincorrected, but approximately one-third of the NALC data 

(path and rows) had been processed before the implementation 

of terrain-correction techniques. However, this was not 

considered a problem because the early NALC scenes were 

located primarily in areas with negligible terrain variability.

Ancillary Data

Additional ancillary data were acquired to aid 

interpreters in delineating land use and land cover from 

the Landsat data. For example, aerial photography was 

acquired for each sample block to provide a high-resolution 

data source to help with difficult interpretations. The 

National Aerial Photography Program (NAPP) generally 

provided one or two dates of color-infrared (CIR) and 

(or) black-and-white aerial photographs from 1987 to the 

present. The National High Altitude Photograph (NHAP) 

Program generally provided one date of CIR and (or) 

black-and-white aerial photographs between 1980 and 

1986. Although the Landsat imagery was always used 

as the source material for delineating land use and land 

cover, these higher resolution aerial photographs were 

invaluable for assisting in the interpretation of the imagery. 

Topographic maps, census data, other electronic sources 

of aerial photographs (for example, Google Earth), and 

digital raster graphics were among the other sources of 

information that interpreters found useful when processing 

the data.

Land-Cover Classification Scheme

The analysis of land use and land cover change during 

the 1973 to 2000 study period was based on classifications 

of land cover for the five target dates mentioned previously. 

The classification system used consists of the following 11 

general land-cover classes: water, developed, mechanically 

disturbed, mining, barren, forest, grassland/shrubland, 

agriculture, wetland, nonmechanically disturbed, and ice/

snow. See appendix 3, entitled “Land-Cover Classification 

System Used in ‘Status and Trends of Land Change’ 

Study,” for definitions of these 11 classifications.

Two primary factors affected the design of the 

classification system. The first factor was recognizing that 

the use of moderate-resolution Landsat imagery would 

necessitate a land-cover classification system that was fairly 

general in order to achieve high interpretation accuracy 

and consistency. The ability to identify and map land cover 

would be limited both by the technical specifications of 

the Landsat MSS, TM, and ETM sensors and by the local 

and regional landscape characteristics that affect the form 

and contrast visible in satellite imagery. This would be 

especially true when interpreting Landsat MSS data. 

The second factor involved choosing land-cover 

classes that captured the land-cover changes of interest. 

Because the project’s interest was in land-use change, with 

land cover serving as a surrogate for land use, the decision 

was to use the Anderson Level I classes (Anderson and 

others, 1976) because they were designed as use surrogates. 

However, the Anderson system was selectively modified by 

adding two disturbance categories, mechanically disturbed 

(human induced) and nonmechanically disturbed (natural). 
186 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000

Manual Land-Cover Delineation

Land-cover delineation for each sample block began 

with the creation of a baseline reference land-cover dataset. 

The 1992 date usually was the starting point owing to the 

availability of the 30-m-resolution 1992 National Land Cover 

Data (NLCD) dataset (Vogelmann and others, 2001). The 

NLCD dataset provided a starting template after the more 

detailed NLCD classes were aggregated to match the general 

land-cover classification described above. 

The NLCD data first were manually edited on the 

computer screen, using on-screen interpretation methods, 

while using the 1992 Landsat TM data and the NAPP aerial 

photographs as interpretation aids. This cleanup procedure to 

improve the NLCD classification accuracy was carried out 

because the NLCD data were created using automated imageprocessing procedures, and they were not meant for use in 

local- or ecoregional-scale assessments. A minimum mapping 

unit of 60 × 60 meters was used for this study. Thus, features 

having ground footprints less than 60 m wide generally 

were not mapped, resulting in the exclusion of high-contrast 

features such as roads, which have a distinct spectral signature 

but have ground dimensions of less than 60 m.

To carry out the NLCD editing for a particular sample 

block, the analyst displayed the NLCD data alongside 

the 1992 Landsat TM data on the computer screen. These 

data sources, along with hard-copy prints of NAPP aerial 

photography roughly corresponding to the 1992 date, 

were visually inspected by the analyst to determine if any 

corrections were needed in the sample block. The analyst 

manually delineated polygons that consisted of contiguous 

blocks of specific land-cover classes. Each of these polygons 

was then given a code value that corresponded to the 

land-cover classes outlined in the classification scheme in 

appendix 3. The process continued until the entire sample 

block was manually inspected, mapped, and coded by the 

analyst.

To analyze change, land-cover classes for the 1973, 

1980, 1986, and 2000 study dates were backward- or forwardclassified using the 1992 land-cover dataset as the template. 

For example, creation of the 2000 land-cover product began 

by making an exact copy of the 1992 land-cover product. This 

copy served as a baseline for the 2000 land-cover product, 

in which identified changes between 1992 and 2000 were 

manually edited into the copied image. This baseline 2000 

land-cover product was displayed on screen, along with the 

1992 Landsat imagery and the 2000 Landsat imagery, allowing 

the analyst to pan through the entire area of the sample block 

while examining the 1992 and 2000 Landsat imagery and 

any relevant aerial photography for valid land-cover changes 

between the two study dates. Any identified land-cover 

changes were manually digitized on screen, and the land cover 

was recoded on the 2000 land-cover product. 

Upon completion of the 2000 land-cover product, the 

same procedures were used to create the 1986, 1980, and 1973 

land-cover products. This manual process eliminated errors 

that may occur between independently created land-cover 

products that are compared in a subsequent change analysis. 

Because only manually identified, delineated, and coded landcover changes were analyzed during this phase, classification 

errors were greatly reduced.

Statistical Analysis

The resulting land-cover data for each sample block 

was used in postclassification comparisons to determine 

change between study years (fig. 2). Sample blocks within 

each ecoregion were used to generate change statistics for 

all 84 ecoregions. These statistics were used to determine 

the predominant types of land-cover conversions occurring 

within each ecoregion, the estimated rates of change for these 

conversions, and whether these types and rates of change are 

constant or variable across time. The analysis of change also 

involved looking for spatial correlations between conversion 

types and selected socioeconomic and environmental factors, 

such as timber production, agricultural yields, precipitation 

amounts, population levels, proximity to urban development, 

and overall economic conditions, in order to improve the 

understanding of potential drivers of change.
Appendix 4. Methodology Used in “Status and Trends of Land Change” Study 187

70°

80°

80°

90°

90°

100°

100°

110°

110° 120°

45° 45°40° 40°35° 35°30° 30°

25° 25°

CANADA

MEXICO

0 200 400 600 MILES0 200 400 600 KILOMETERS

Total change

10 × 10 km20 × 20 km

, as

EXPLANATION

percent of ecoregion

0 – 4.14.2 – 7.57.6 – 14.414.5 – 33.8

Ecoregion boundary

Sample blocks

Figure 4.1. Map of ecoregions in conterminous United States, showing locations of 2,688 sample blocks that were used in “Status and Trends of Land Change” study 

(purple and blue squares indicate locations of 10 × 10 km and 20 × 20 km sample blocks, respectively). Also shown are amounts of total change in each ecoregion between 1973 and 2000, as percent of ecoregion. 
188 Status and Trends of Land Change in the Midwest–South Central United States—1973 to 2000 

1973–1980

1980–1986

1986–1992

1992–2000

Forest

Grassland/Shrubland

Mining

Water

Barren

Mechanically disturbed

Developed

Land-use/land-cover class

1973

Landsat images Mapped land-use/land-cover Areas of change

1980

1986

1992

2000

Figure 4.2. Example of data compiled for each sample block, showing sample block 14-0555 (located near 

Henderson, Nevada, in Mojave Basin and Range Ecoregion, one of Western United States ecoregions). Left 

column is satellite imagery collected for each of five years analyzed in study (imagery sources for study 

years: 1973, 1980, and 1986 are Landsat Multispectral Scanner (MSS) images; 1992 is Landsat Thematic 

Mapper (TM) image; 2000 is Landsat Enhanced Thematic Mapper (ETM) image). Center column is mapped 

land-use/land-cover data for each study year. Right column shows areas that changed (green areas) in 

each of four time periods between study years; light- and dark-gray-shaded areas show areas of previous 

change and represent overall land-change footprint throughout study period.
Appendix 4. Methodology Used in “Status and Trends of Land Change” Study 189

References Cited

Anderson, J.R., Hardy, E.E., Roach, J.T., and Witmer, R.E., 

1976, A Land Use and Land Cover Classification System 

for Use with Remote Sensor Data: U.S. Geological Survey 

Professional Paper 964, 28 p., available at http://pubs.usgs.

gov/pp/0964/report.pdf.

Kish, L., 1987, Statistical Design for Research: New York, 

John Wiley & Sons, Inc., 296 p.

Loveland, T.R., and Shaw, D.M., 1996, Multiresolution land 

characterization—Building collaborative partnerships, 

in Scott, J.M., Tear, T.H., and Davis, F.W., eds., Gap 

Analysis—A landscape approach to biodiversity planning: 

Bethesda, Maryland, American Society for Photogrammetry 

and Remote Sensing, p. 17–25.

Loveland, T.R., Sohl, T.L., Stehman, S.V., Gallant, A.L., 

Sayler, K.L., and Napton, D.E., 2002, A strategy for 

estimating the rates of recent United States land cover 

changes: Photogrammetric Engineering and Remote 

Sensing, v. 68, no. 10, p. 1,091–1,099.

Lunetta, R.S., Lyon, J.G., Guindon, B., and Elvidge, C.D., 

1998, North American landscape characterization dataset 

development and data fusion issues: Photogrammetric 

Engineering and Remote Sensing, v. 64, no. 8, p. 821–829.

Omernik, J.M., 1987, Ecoregions of the conterminous United 

States: Annals of the Association of American Geographers, 

v. 77, no. 1, p. 118–125.

Turner, B.L., II, and Meyer, W.B., 1991, Land use and land 

cover in global environmental change—Considerations for 

study: International Social Science Journal, v. 130, 

p. 669–677.

U.S. Environmental Protection Agency, 1999, Level 

III Ecoregions of the continental United States: U.S. 

Environmental Protection Agency National Health 

and Environmental Effects Research Laboratory, scale 

1:7,500,000, available at ftp://ftp.epa.gov/wed/ecoregions/

usgs/useco_March 1999_v5.pdf.

Vogelmann, J.E., Howard, S.M., Yang, L., Larson, C.R., 

Wylie, B.K., and van Driel, N., 2001, Completion of the 

1990s National Land Cover Data Set for the conterminous 

United States from Landsat Thematic Mapper data and 

ancillary data sources: Photogrammetric Engineering & 

Remote Sensing, v. 67, p. 650–662.
Produced in the Menlo Park Publishing Service Center, Menlo Park, California

Manuscript approved for publication August 10, 2015

Edited by Taryn A. Lindquist and John S. Osias

Design and layout by Jeanne S. DiLeo and David R. Jones

ISSN 1044-9612 (print) 

ISSN 2330-7102 (online) 

http://dx.doi.org/10.3133/pp1794C

Printed on recycled paper