United States

Department of

Agriculture

Forest Service

Northern

Research Station

General Technical

Report NRS-59

Urban and Community Forests

of the South Central West Region

Arkansas

Louisiana

Oklahoma

Texas

David J. Nowak

Eric J. Greenfi eld
Printed on Recycled Paper

Published by: For additional copies:

U.S. FOREST SERVICE U.S. Forest Service

11 CAMPUS BLVD SUITE 200 Publications Distribution

NEWTOWN SQUARE, PA 19073 359 Main Road

 Delaware, OH 43015

March 2010 Fax: (740) 368-0152

Visit our homepage at: http://www.nrs.fs.fed.us/

The Authors

DAVID J. NOWAK is a research forester and project leader, and ERIC J. GREENFIELD is 

a forester with the Forest Service’s Northern Research Station at Syracuse, NY.

Manuscript received for publication 30 September 2009

Abstract

This report details how land cover and urbanization vary within the states of Arkansas, 

Louisiana, Oklahoma, and Texas by community (incorporated and census designated 

places), county subdivision, and county. Specifi cally this report provides critical urban and 

community forestry information for each state including human population characteristics 

and trends, changes in urban and community lands, tree canopy and impervious surface 

cover characteristics, distribution of land-cover classes, a relative comparison of urban 

and community forests among local government types, determination of priority areas for 

tree planting, and a summary of urban tree benefi ts. Report information can improve the 

understanding, management, and planning of urban and community forests. The data 

from this report is reported for each state on the CD provided in the back of this book, 

and it may be accessed by state at: http://www.nrs.fs.fed.us/data/urban.
CONTENTS

 Introduction 1

 Report Overview 2

 Urban Forest Attributes 2

 Summary 10

 Acknowledgments 10

 Arkansas’ Urban and Community Forests 11

 Louisiana’s Urban and Community Forests 19

 Oklahoma’s Urban and Community Forests 27

 Texas’ Urban and Community Forests 35

 Literature Cited 43

 Appendix 46
GTR-NRS-59 1

INTRODUCTION

As part of the Forest and Rangeland Renewable Resources Planning Act of 1974, the 

fi rst national assessment of urban forests was completed in 2000 (Dwyer et al. 2000, 

Nowak et al. 2001b). This assessment used 1-km resolution Advanced Very-High 

Resolution Radiometer (AVHRR) data (Zhu 1994) and 1990 U.S. Census Bureau 

(2007) population and geographic data to assess urban tree cover. The assessment 

concluded that urban areas in the conterminous United States doubled in size 

between 1969 and 1994 and covered 3.5 percent of the total land area. Urban areas 

were estimated to contain approximately 3.8 billion trees with an average tree canopy 

cover of 27 percent.

To update this fi rst report, higher resolution (30 m) tree canopy and impervious 

surface cover maps were used (from 2001 Landsat satellite imagery and published 

in 2007) (Homer et al. 2007, U.S. Geol. Surv. 2007) in conjunction with 1990 and 

2000 census and geographic data (1:5,000,000 scale cartographic boundary fi les) 

(U.S. Census Bureau 2007) to assess current urban and community forest attributes. 

These results are being published for each of the lower 48 United States to provide 

information on urban change and state-specifi c urban and community forestry data.

This report includes information for the following states: Arkansas, Louisiana, 

Oklahoma, and Texas.

Data are reported for the state, county, county subdivision, and community 

jurisdictions. The jurisdictional units used in this report are derived from U.S. Census 

(2007) geographic data and defi ned legal or statistical divisions. “County”1

 refers to 

the primary subdivision within states. “County subdivisions” are primary divisions 

of a county and are statistically equivalent entities for the reporting of census data. 

They include census county divisions (CCD), census sub areas, minor civil divisions 

(MCD), and unorganized territories. “Communities” are incorporated and census 

designated places, and consolidated cities (U.S. Census Bureau 2007). For detailed 

defi nitions, see http://www.census.gov/geo/www/cob/cs_metadata.html (2007).

1

The primary legal divisions of most states are termed “counties.” In Louisiana, these 

divisions are known as “parishes.” In four states (Maryland, Missouri, Nevada, and Virginia), 

there are one or more incorporated places that are independent of any county organization 

and thus constitute primary divisions of their states; these incorporated places are known as 

“independent cities” and are treated as equivalent to counties for statistical purposes. (For 

some statistical purposes they may be treated as county subdivisions and places.) The District 

of Columbia has no primary divisions, and the entire area is considered equivalent to a county 

for statistical purposes. (http://www.census.gov/geo/www/cob/co_metadata.html, 2007)
2 GTR-NRS-59

REPORT OVERVIEW

The information in this report can aid local and 

regional managers and planners of urban and 

community forest resources. This report provides 

urban and community forest reference information 

and data from the state to local level on the following 

attributes related to the urban and community forest 

resource:

• Human population characteristics and trends

• Urban and community land

• Tree canopy cover characteristics 

• Impervious surface cover characteristics

• Classifi ed land-cover characteristics

• Relative comparisons of urban and community 

forests 

• Priority areas for tree planting

• Urban tree benefi ts

Information in this report can be used by urban and 

community forestry professionals to:

• Understand general land-cover characteristics 

and urbanization trends at several geographic 

scales

• Compare tree canopy cover among similar 

communities

• Determine areas of greatest growth and areas of 

highest tree planting priority

• Relate urban and community forests to pollution 

removal and carbon storage

• Promote more detailed and/or locally appropriate 

urban and community forest inventories, 

censuses, or fi eld surveys (e.g., i-Tree – 

www.itreetools.org) 

• Establish local to statewide standards related to 

urban and community forestry

• Support urban and community forestry programs 

• Improve urban and community forest 

management and planning

The remainder of this section details how information 

was derived for each attribute reported for the urban 

and community areas. The subsequent state summaries 

detail the fi ndings for each state in this region. Most 

tables for each state are not given in this report, rather 

they can be found on the CD provided with this report 

or accessed at: http://www.nrs.fs.fed.us/data/urban.

URBAN FOREST ATTRIBUTES

Human Population Characteristics and 

Trends

Human population and population density changes 

over time, and geographic distribution are important 

measurements of the urban environment because 

human populations are an integral part of community 

and urban forest dynamics. Within divisions of state, 

county, county subdivision, and community, total 

population, population changes from 1990 to 2000 and 

population density are detailed based on U.S. Census 

data (U.S. Census Bureau 2007).

Urban and Community Land

Two geographic defi nitions overlap: “community” 

and “urban”. The defi nition of community is based 

on jurisdictional or political boundaries delimited by 

U.S. Census defi nitions of places (U.S. Census Bureau 

2007). Community lands are places of established 

human settlement that may include all, some, or no 

urban land within their boundaries.

The defi nition of urban is based on population density 

as delimited using the U.S. Census Bureau’s (2007) 

defi nition: all territory, population, and housing units 

located within urbanized areas or urban clusters. 

Urbanized area and urban cluster boundaries 

encompass densely settled territories, which are 

described by one of the following:

• One or more block groups or census blocks with 

a population density of at least 386.1 people/ 

km2

 (1,000 people/mile2)

• Surrounding block groups and census blocks 

with a population density of 193.1 people/km2

(500 people/mile2

)

• Less densely settled blocks that form enclaves 

or indentations, or are used to connect 

discontinuous areas
GTR-NRS-59 3

More specifi cally, urbanized areas consist of territory 

with 50,000 or more people. Urban clusters, a concept 

new to the 2000 Census, consist of territory with at 

least 2,500 people but fewer than 50,000 people. This 

new defi nition tends to be more restrictive than the 

1990 U.S. Census urban defi nition and encompasses 

many areas typically considered suburban. The 2000 

Census defi nition of urban was applied to 1990 Census 

geographic data to analyze change in urban land 

between 1990 and 2000 (Nowak et al. 2005).

As urban land reveals the more heavily populated areas 

(population density-based defi nition) and community 

land indicates both urban and rural (i.e., non-urban) 

communities that are recognized by their geopolitical 

boundaries (political defi nition), both defi nitions 

provide information related to human settlements and 

the forest resources within those settlements. As some 

urban land exists beyond community boundaries and 

not all community land is urban (i.e., communities 

are often a mix of urban and rural land), the category 

of “urban or community” was created to understand 

forest attributes accumulated by the union of these 

two defi nitions. The “urban or community” term used 

throughout this report encompasses both urban land 

and land in communities.

Percent urban land is a ratio of urban land over total 

land within a census geographic division, and percent 

community land is a ratio of community land over 

total land within the geopolitical unit. In addition, 

changes in urban land and changes in community land 

are reported between 1990 and 2000.

For each state, Tables 1 through 4 summarize the 

population, and urban and community land attributes 

for the state, communities, county subdivisions, and 

counties respectively (CD and http://www.nrs.fs.fed.

us/data/urban).

Tree Canopy Cover Characteristics

Tree canopy cover is a critical measure of the urban 

and community forest resource. Tree canopy cover 

gives a broad indication of the overall forest resource 

and its associated benefi ts. To assess urban and 

community land cover characteristics, the multiresolution land characteristics consortium’s National 

Land Cover Database (NLCD) was used (Homer et 

al. 2004, U.S. Geol. Surv. 2007, Yang et al. 2003). 

The NLCD, released in early 2007, was processed 

from 2001 Landsat satellite imagery and provides 

estimates of percentage tree canopy and impervious 

surface cover within 30-m pixels or cells across the 

state. The tree canopy percentages in this report are 

calculated using the land area (not including water) 

of the geopolitical units derived from the U.S. Census 

cartographic boundary data and NLCD. In addition 

to percentage tree cover, four other canopy cover 

attributes, derived from the same data, were assessed:

• Tree canopy cover per capita—Tree canopy 

cover (m2

) divided by the number of people 

within the area of analysis.

• Total green space—Total area minus impervious 

and water cover (ha). This attribute estimates 

pervious cover (i.e., grass, soil, or tree-covered 

areas).

• Canopy green space—Tree cover divided by 

total green space (percent). This value is the 

proportion of the total green space that is fi lled 

by tree canopies.

• Available green space—Total green space minus 

tree canopy cover (ha). This value is the amount 

of grass and soil area not covered with tree 

canopies and potentially available for planting.

Impervious Surface Cover 

Characteristics

Similar to tree cover, impervious surface cover 

provides another piece of valuable information 

related to the urban environment. Impervious surface 

cover gives an indication of an area’s developed 

hardscape, which has important infl uences on urban 

air temperatures and water fl ows and also yields 

information on limitations to urban tree cover. 

Impervious surface cover also was derived from 

the NLCD database (U.S. Geol. Surv. 2007). The 

impervious surface cover percentages in this report are 

calculated using the land area (not including water) 

of the geopolitical units derived from the U.S. Census 
4 GTR-NRS-59

cartographic boundary data and NLCD. Impervious 

surface per capita is calculated from NLCD 2001 and 

U.S. Census data.

For each state, Tables 1, and 5 through 7 summarize 

the tree canopy and impervious surface cover attributes 

for the state, communities, county subdivisions, and 

counties respectively (CD and http://www.nrs.fs.fed.

us/data/urban).

Classifi ed Land-cover Characteristics

Land-cover types also are summarized using 2001 

Landsat satellite data that were classifi ed with the U.S. 

Geological Survey land cover categorization scheme 

based on a modifi ed Anderson land-cover classifi cation 

(U.S. Geol. Surv. 2007). Land area, tree canopy cover, 

and available green space within generalized land 

cover categories vary among communities, county 

subdivisions, counties, and state. The percentages 

are calculated from the NLCD 2001 and U.S. Census 

cartographic boundary data. The land-cover categories 

defi ned here are derived from established NLCD 2001 

land-cover classes. These generalized land-cover 

categories or types may not be present in some states.

• Developed—NLCD classes 21 (developedopen space), 22 (developed-low intensity), 

23 (developed-medium intensity), and 24 

(developed-high intensity) 

• Barren—NLCD class 31 (barren land [rock/

sand/clay])

• Forested—NLCD classes 41 (deciduous forest), 

42 (evergreen forest), and 43 (mixed forest)

• Shrub/Scrub—NLCD class 52 (shrub/scrub)

• Grassland—NLCD class 71 (grassland/

herbaceous)

• Agriculture—NLCD classes 81 (pasture/hay) 

and 82 (cultivated crops)

• Wetland—NLCD classes 90 (woody wetlands) 

and 95 (emergent herbaceous wetlands)

For each state, Tables 8 through 10 summarize the 

classifi ed land-cover characteristics for communities, 

county subdivisions, and counties and state 

respectively (CD and http://www.nrs.fs.fed.us/data/

urban).

Relative Comparisons of Tree Cover

A question commonly asked in evaluating the urban 

and community forest resource is, “How does my 

community compare with other communities?”

To help answer this question, tree canopy cover was 

compared among the counties, county subdivisions, 

and communities relative to other areas with 

comparable population density and within the same 

NLCD mapping unit (ecoregion). For this comparison, 

seven population density classes were established:

• Density class 1 — 0 to 38.6 people/km2

(0 to 99.9 people/mile2

)

• Density class 2 — 38.7 to 96.5 people/km2

(100 to 249.9 people/mile2

)

• Density class 3 — 96.6 to 193.1 people/km2

(250 to 499.9 people/mile2

)

• Density class 4 — 193.2 to 289.6 people/km2

(500 to 749.9 people/mile2

)

• Density class 5 — 289.7 to 386.2 people/km2

(750 to 999.9 people/mile2

) 

• Density class 6 — 386.3 to 1931.2 people/km2

(1000 to 4999.9 people/mile2

) and 

• Density class 7 — 1931.3 or greater people/km2

(5000 or greater people/mile2

)

Mapping zones were delimited within the NLCD to 

increase classifi cation accuracy and effi ciency (Fig. A). 

The mapping units represent relatively homogeneous 

ecological conditions (Homer and Gallant 2001). 

To locate geopolitical units within a mapping zone, 

centroid (geometric center) points of the local 

governments were used.

For three or more geographic units in the same 

mapping zone and population density class, a 

standardized tree canopy score based on the range of 

values within that zone and class was assigned to each 

unit. The standardized score is calculated as:

Standardized score = (tree canopy percent of unit 

– minimum tree canopy percentage in class)/range of 

tree canopy percent in class.
GTR-NRS-59 5

Communities, county subdivisions, and counties were 

assigned to one of the following categories based on 

their standardized score:

• Excellent—Standardized score of 0.9 to 1.0

• Very Good—0.7 to 0.89

• Good—0.5 to 0.69

• Fair—0.3 to 0.49

• Poor—0 to 0.29

To help understand the variability of tree cover, 

minimum, median, maximum, and weighted 

mean values for percent tree canopy cover in each 

population density class of each political subdivision 

are reported in Table 11 for each mapping zone 

(CD and http://www.nrs.fs.fed.us/data/urban). This 

information can be used to understand the actual range 

and values used for the assessment.

For each state, Tables 12 through 14 summarize the 

urban and community forest ratings for communities, 

county subdivisions, and counties respectively (CD 

and http://www.nrs.fs.fed.us/data/urban).

Figure A.—The mapping zones of the continental United States relative to states and land cover (NLCD 2001).

Priority Areas for Tree Planting

NLCD (U.S. Geol. Survey 2007) and 2000 U.S. 

Census data (2007) were used to produce an index that 

prioritizes tree planting areas for communities, county 

subdivisions, and counties. An index was developed 

to help identify areas with relatively low tree canopy 

cover and high population density (high priority 

tree-planting areas). This index provides one form 

of prioritization. States and local governments may 

design their own prioritization method incorporating 

individual and diverse value systems. The index used 

in this report combines three criteria.

• Population density—The greater the population 

density, the greater the priority for tree planting

• Canopy green space—The lower the value, the 

greater the priority for tree planting

• Tree canopy cover per capita—The lower the 

amount of tree canopy cover per person, the 

greater the priority for tree planting
6 GTR-NRS-59

Each criterion above was standardized2 on a scale of 

0 to 1, with 1 representing the maximum population 

density and minimum canopy green space and tree 

cover per capita. The standardized values were 

weighted to produce a combined score: 

I = (PD * 40) + (CG * 30) + (TPC * 30)

Where I is the combined index score 

PD is the standardized population density value 

CG is the standardized canopy green space value, and 

TPC is the standardized tree cover per capita value. 

The combined score was standardized again and 

multiplied by 100 to produce the planting priority index. 

The tree planting priority index (PPI) ranks each state’s 

communities, county subdivisions, and counties with 

values from 100 (highest priority) to 0 (lowest priority). 

This index is a type of “environmental equity” index 

with areas of higher human population density and 

lower canopy green space and tree cover per capita 

tending to get the higher index value.

For each state, Tables 15 through 17 summarize the 

tree planting priority index for communities, county 

subdivisions, and counties respectively (CD and 

http://www.nrs.fs.fed.us/data/urban).

Urban Tree Benefi ts

Urban and community forests are important for human 

and ecological health (Nowak and Dwyer 2007). The 

benefi ts ascribed to urban and community trees include:

2

Standardized value for population density (PD) was 

calculated as PD=(n–min)/r, where PD is the value 0-1, 

n is the value for the geopolitical unit (population/km2), 

min is the minimum value for all units, and r is the range 

of values among all units (maximum value – minimum 

value). Standardized value for canopy green space (CG) was 

calculated as CG=(max–n)/r, where CG is the value 0-1, 

max is the maximum value for all geopolitical units, n is the 

value for the unit (tree canopy cover m2/total green space 

m2), and r is the range of values. Standardized value for tree 

cover per capita (TPC) was calculated as TPC=(max–n)/r, 

where TPC is the value (0-1), max is the maximum value for 

all geographic units, n is the value for the geopolitical unit 

(m2/capita), and r is the range of values among all units.

• Carbon storage and sequestration

• Air pollution removal

• Surface air temperature reduction 

• Reduced building energy use

• Absorption of ultraviolet radiation

• Improved water quality

• Reduced noise pollution

• Improved human comfort

• Increased property value

• Improved human physiological and 

psychological well-being

• Improved aesthetics

• Improved community cohesion 

To understand the contribution and magnitude of the 

forest resource in urban or community areas, the total 

number of trees, carbon storage and annual carbon 

uptake (sequestration), air pollution removal, and the 

associated dollar values for carbon and air pollution 

benefi ts are estimated.

Carbon sequestration and storage values were 

estimated from tree cover (m2

) multiplied by average 

carbon storage (9.1 kg C/m2

), and sequestration 

(0.3 kg C/m2

) density values derived from several U.S. 

communities (e.g., Nowak and Crane 2002). Monetary 

values associated with urban tree carbon storage and 

sequestration were based on the 2001-2010 projected 

marginal social cost of carbon dioxide emissions, 

$22.8/t C (Fankhauser 1994). The number of urban 

and community trees was estimated in a similar 

manner multiplying tree canopy cover (m2

) by average 

tree density per hectare of canopy cover from several 

U.S. cities (Table A).

Air pollution removal estimates are derived from the 

Urban Forest Effects (UFORE) model (Nowak and 

Crane 2000) and 2000 weather and pollution data 

(National Climatic Data Center 2000, U.S. EPA 2008). 

The UFORE model was used to integrate hourly 

pollution and weather data with urban or community 

tree cover data to estimate annual pollution removal 

in each state (Nowak and Crane 2000, Nowak et al. 

2006d).
GTR-NRS-59 7

To estimate pollution by urban trees in each state, state 

pollutant fl ux rates (grams of pollution removal per 

square meter of canopy per year) were derived from 

a study of national pollution removal by urban trees 

for the year 1994 (Nowak et al. 2006d). As pollution 

concentrations vary through time, the 1994 fl ux 

rates were adjusted to 2000 values based on average 

regional pollution concentration changes between 

1994 and 2000 (U.S. EPA 2003). As

fl ux rate = deposition velocity * pollution 

concentration,

the ratio of the pollution concentration between years 

was used to update the fl ux rate. Arithmetic mean 

concentration values were used for nitrogen dioxide, 

particulate matter less than 10 microns, and sulfur 

dioxide, 2nd Max. 8-hr average for carbon dioxide, 

and 4th Max. 8-hr average for ozone, to determine 

the ratio of change between 1994 and 2000 (U.S. EPA 

2003). The new 2000 fl ux rates were multiplied by 

urban or community tree cover in the state to estimate 

total pollution removal by trees.

Pollution removal dollar value estimates were 

calculated using 1994 national median externality 

values used in energy decision making (Murray et 

al. 1994, Ottinger et al. 1990). The 1994 values were 

adjusted to 2007 dollars based on the producer price 

index (U.S. Dept. of Labor 2008). These values, in 

dollars/metric ton (t) are: 

• Nitrogen dioxide (NO2

) = $9,906/t

• Particulate matter less than 10 microns (PM10) = 

$6,614/t

• Sulfur dioxide (SO2

) = $2,425/t

• Carbon monoxide (CO) = $1,407/t

Table A.—Average number of trees, carbon storage, and carbon 

sequestration rates per unit of canopy cover for several U.S. cities

a Unpublished data analyzed using UFORE model

b Nowak 1994a,b

c

 Nowak et al. 2006a

d Nowak et al. 2006b

e Nowak et al. 2007a

f

 Nowak et al. 2007b

g Nowak et al. 2007c

h Nowak et al. 2001a

i

 Nowak 1993; Nowak and Crane 2002

j

 Nowak et al. 2006c

 Carbon

 Trees Storage Sequestration

City (no./ha cover) (kg C/m2 cover) (kg C/m2 cover)

Atlanta, GA a 751.5 9.7 0.3

Baltimore, MD a 598.1 12.3 0.3

Boston, MA a 371.7 9.1 0.3

Chicago, IL b 618.0 12.9 n/a

Casper, WY c 252.8 7.0 0.2

Freehold, NJ a 275.0 10.4 0.3

Jersey City, NJ a 308.7 4.4 0.2

Minneapolis, MN d 245.5 5.7 0.2

Moorestown, NJ a 547.9 9.9 0.3

Morgantown, WV a 829.6 10.6 0.3

New York, NY e 312.0 7.3 0.2

Philadelphia, PA f

 394.3 9.0 0.3

San Francisco, CA g 468.1 12.3 0.3

Syracuse, NY h 583.1 10.5 0.3

Oakland, CA i 570.0 5.2 n/a

Washington, DC j

 423.4 10.4 0.3

Woodbridge, NJ a 557.3 8.2 0.3

Mean 476.9 9.1 0.3
8 GTR-NRS-59

Externality values for ozone (O3) were set to equal the 

value for NO2

. Externality values can be considered 

the estimated cost of pollution to society that is not 

accounted for in the market price of the goods or 

services that produced the pollution.

For each state, Table 1 summarizes carbon storage and 

air pollution removal estimates for urban, community, 

and urban or community trees statewide.

Data Accuracy and Application

The data presented in this report yield the most 

comprehensive and up-to-date assessment of 

continental U.S. urban and community forests. 

The data allows for relative comparisons among 

geographies and provides baseline information for 

assessing relative changes in urban and community 

forest cover in the future. As stated previously, tree 

cover information was based on fi ner resolution data 

than used in the original urban forest assessment 

(Dwyer et al. 2000). As the methodologies for 

quantifying tree cover have changed between the 

original and current assessment, evaluating changes 

is not possible since the detected changes could 

be caused by either actual landscape changes or 

differences in methodology.

The U.S. Census generalized cartographic boundary 

data are a simplifi ed and smoothed extracts of the 

Topologically Integrated Geographic Encoding and 

Referencing (TIGER) database, with a target scale 

range of 1:5,000,000 (U.S. Census Bureau 2007). 

Because of this scale and generalization, border 

simplifi cation impacts attribute measurements that are 

derived from the boundary data, especially for small 

areas and at the local scale. In particular, percentages 

(unitless ratios) generated from attribute measurements 

made for the smallest communities or county 

subdivisions may be under- or overstated depending 

upon the relative location of the smoothed border of 

the geopolitical unit.

While the 2001 NLCD is a substantial improvement 

over the 1991 AVHRR data (30-m versus 1-km 

resolution), it also has local-scale data and application 

limitations. Initial tree canopy cover results revealed 

mean absolute errors (mean of the absolute difference 

between predicted and actual values) from 8.4 percent 

to 14.1 percent, with correlation coeffi cients between 

predicted and actual values ranging from 0.78 to 

0.93. Impervious surface cover results revealed mean 

absolute errors from 4.6 percent to 7 percent, with 

r-values from 0.83 to 0.91 (Homer et al. 2004).

A more recent analysis of 127 community and 

20 county geographies sampled throughout the 

continental United States compared NLCD tree 

canopy and impervious surface cover estimates 

with high resolution (1-m or less resolution) aerial 

photo-interpreted estimates. This analysis revealed 

that NLCD underestimates both tree canopy and 

impervious surface cover compared to photointerpreted values. NLCD underestimates of tree 

cover vary by mapping zone, while underestimates of 

impervious surface cover, which are relatively minor, 

varies by population density (Greenfi eld et al. 2009). 

These fi ndings are consistent with Walton (2008), who 

found a consistent under-prediction bias for the 2001 

NLCD derived tree canopy cover values in census 

places (communities) of western New York.

The tree cover and impervious cover data given in this 

report are directly from the NLCD database. To help 

understand the potential underestimate in the cover 

values, each U.S. mapping zone was photo-interpreted 

using Google Earth images3

. Table B provides a 

comparison of results from NLCD versus photointerpreted data for mapping zones applicable to this 

collection of states.

Comparisons between NLCD impervious surface 

cover estimates and photo-interpreted values were 

not reported because differences were related to 

population density, which can vary signifi cantly among 

geographic units. Despite the potential underestimates 

in tree canopy cover values, relative comparisons 

3

Nowak, D.J.; Greenfi eld, E.J. Tree and impervious cover 

in the conterminous United States: Testing of NLCD cover 

estimates by mapping zone. In review. 
GTR-NRS-59 9

Margin Signifi cant

Mapping zone a n b NLCD c PI d Difference e of error f difference g

 25 942 6.2% 14.7% 8.5% 2.3% Yes

 26 866 0.8% 8.5% 7.8% 1.9% Yes

 27 997 3.3% 8.3% 5.1% 1.7% Yes

 32 619 13.4% 23.0% 9.6% 2.7% Yes

 34 929 1.2% 8.1% 6.9% 1.7% Yes

 35 987 13.2% 18.1% 4.9% 2.4% Yes

 36 998 10.8% 27.6% 16.8% 2.5% Yes

 37 959 43.4% 56.9% 13.4% 2.4% Yes

 38 497 3.3% 4.1% 0.8% 1.6% No

 43 594 12.8% 23.1% 10.3% 2.7% Yes

 44 913 50.0% 60.6% 10.7% 2.1% Yes

 45 989 17.8% 23.3% 5.5% 1.5% Yes

 46 709 55.9% 70.6% 14.7% 2.8% Yes

a NLCD mapping zones e PI value minus NLCD value b Number of photo-interpreted sample points f

 95% confi dence interval of PI value c

 Percent tree canopy value derived from NLCD data g Signifi cant difference between NLCD and PI values if NLCD value d Percent tree canopy derived from photo-interpreted data is outside of 95% confi dence interval of PI value

Percent tree canopy cover

Table B.—Comparison of NLCD versus photo-interpretation (PI) derived values of percent tree canopy 

cover by NLCD mapping zones

of tree cover among geographies in this report (e.g., 

planting priority index and the ratings of excellent to 

poor for local government tree cover) are reasonable 

as the under-prediction of tree cover is fairly 

consistent within each mapping zone. However, it is 

important to note that the tree canopy and impervious 

surface cover could be underestimated, as well as 

their associated ecosystem services and values. A 

forthcoming analysis will better assess the accuracy of 

the NLCD cover maps (Homer et al. 2007), but these 

maps and data provide comprehensive, consistent, 

and comparable estimates (with an inherent degree of 

error and uncertainty) of tree canopy and impervious 

surface cover to help urban and community forest 

management, planning and policy making. Higher 

resolution cover data may provide more accurate 

results at the local scale, but the NLCD cover maps 

provide a cost-effective means to consistently 

assess and compare the relative differences of urban 

cover types regionally. For more refi ned and locally 

appropriate data, local fi eld or high resolution 

(1 m or less) image analyses are recommended 

(e.g., i-Tree – www.itreetools.org; UTC – 

www.nrs.fs.fed.us/urban/utc).

Because of limited urban and community forest fi eld 

data, data from several urban and community forests 

were used to estimate the number of trees and carbon 

storage by trees. These coarse estimates reveal that 

urban and community forests contain a large number 

of trees and provide signifi cant environmental benefi ts. 

Field data are needed from all states to help improve 

these estimates as well as to estimate other forest 

effects (e.g., building energy conservation and changes 

in stream fl ow and water quality). Data from longterm monitoring of urban and community forests used 

in conjunction with satellite-based cover maps will 

provide essential information to assess forest health 

and change, and to improve urban and community 

forest management.

Practical Applications for Managers

The data from this report can be used to aid urban 

forest management at both the state and local levels. 

Data can be used to:

• Determine the extent, magnitude, and variation 

in the urban and community forestry resource

• Determine areas of greatest population growth, 

urbanization, and development (sprawl) to direct 

urban and community forestry to minimize 

negative impacts and maximize environmental 

benefi ts 
10 GTR-NRS-59

• Evaluate existing tree canopy, impervious 

surface cover, and available planting space 

(available green space) to direct current and 

future urban and community forestry efforts 

such as planting programs

• Compare tree canopy cover for similar 

geopolitical units and set tree canopy goals 

• Prioritize tree planting based on population 

density, tree canopy green space, and tree 

canopy cover per person

• Understand the pollution removal and carbon 

storage benefi ts of urban and community forests

• Promote more detailed and/or locally 

appropriate urban and community forest 

inventories, censuses, or fi eld surveys 

(e.g. i-Tree – www.itreetools.org)

• Establish statewide to local standards related to 

urban and community forestry (e.g., establishing 

minimum goals of percent canopy green space 

or tree cover per capita and directing resources 

so that communities can reach the minimum 

standards)

• Improve urban and community forest 

management and cost estimation by providing 

an estimate of the number of trees in each 

geopolitical unit (i.e., urban area size (ha) *

percent tree cover * 477 trees/ha, or local tree 

density information from local data)

• Guide policy decisions related to urban sprawl 

and urban and community forest management

SUMMARY

The data presented in this report provide a better 

understanding of urban and community forests. 

This information can be used to advance urban and 

community forest policy and management that could 

improve environmental quality and human health 

throughout the state. The following sections detail 

specifi c urban and community forestry data for the 

states in this regional report.

ACKNOWLEDGMENTS

This research was funded, in part, by the U.S. Forest 

Service’s RPA Assessment Staff, State and Private 

Forestry’s Urban and Community Forestry Program, 

and Northeastern Area State and Private Forestry. 

Thanks also goes to Chris Sorrentino for assistance 

with report compilation, Nana Efua Imbeah for 

assistance with data processing, and Mike Boarman 

for assistance with image processing.
GTR-NRS-59 Arkansas 11

Statewide Summary

Urban or community land in Arkansas comprises about 4.6 percent of the state 

land area in 2000, an increase from 3.8 percent in 1990. Statewide tree canopy 

cover averages 45.7 percent and tree cover in urban or community areas is about 

30.0 percent, with 11.0 percent impervious surface cover and 33.7 percent of the 

total green space covered by tree canopy cover. Statewide, urban or community 

land in Arkansas has an estimated 87.6 million trees, which store about 

16.7 million metric tons of carbon ($380.8 million), and annually remove about 

551,000 metric tons of carbon ($12.6 million) and 16,220 metric tons of air 

pollution ($134.0 million) (Table AR-1).

Tables AR-2 through AR-17 are not printed in this report but are available on the 

CD located on the inside back cover and at http://nrs.fs.fed.us/data/urban.

ARKANSAS’ URBAN 

AND COMMUNITY 

FORESTS
12 GTR-NRS-59 Arkansas

a Urban land is based on population density and was delimited using the United States Census defi nitions of urbanized areas and urban clusters. b Community 

land is based on jurisdictional or political boundaries of communities based on United States Census defi nitions of incorporated or census designated places. c

 Urban or communities is land that is urban, community, or both. Communities may include all, some, or no urban land within their boundaries. d Canopy green 

space is the tree canopy cover divided by total green space. e Total green space (TGS) is total area – impervious surface cover – water. f Available green space 

(AGS) is total green space – tree canopy cover (if the calculated value is less than 0, then value set at 0). 

Arkansas Statewide Urban a Community b

 Urban or

Community c

Population

2000 2,673,400 1,404,179 1,709,147 n/a

1990 2,350,725 1,258,021 1,452,759 n/a

% Change (1990-2000) 13.7 11.6 17.6 n/a

% Total population (2000) 100.0 52.5 63.9 n/a

Total area 

km2 (2000) 137,732.0 2,354.8 5,972.9 6,234.1

km2 (1990) 137,732.0 1,960.0 4,982.3 5,237.5

% Change (1990-2000) 0.0 20.1 19.9 19.0

Land area 

km2 (2000) 134,423.4 2,331.0 5,869.1 6,125.7

% Land area (2000) 100.0 1.7 4.4 4.6

km2 (1990) 134,423.4 1,947.0 4,887.4 5,139.8

% Land area (1990) 100.0 1.4 3.6 3.8

% Change (1990-2000) 0.0 19.7 20.1 19.2

Population density 

 (people/land area km2)

2000 19.9 602.4 291.2 n/a

1990 17.5 646.1 297.2 n/a

% Change (1990-2000) 13.7 -6.8 -2.0 n/a

Tree canopy cover (2000)

km2 61,459.8 592.2 1,748.5 1,837.0

% Land area 45.7 25.4 29.8 30.0

Per capita (m2/person) 22,989.4 421.8 1,023.0 n/a

% Canopy green space d 46.2 31.8 33.6 33.7

Total green space (2000) e km2 133,062.0 1,864.6 5,209.6 5,450.2

% Land area 99.0 80.0 88.8 89.0

Available green space (2000) f km2 71,613.5 1,273.6 3,462.8 3,615.0

% Land area 53.3 54.6 59.0 59.0

Impervious surface cover 

 (2000)

km2 1,361.0 466.4 659.5 675.5

% Land area 1.0 20.0 11.2 11.0

Per capita (m2/person) 509.1 332.1 385.9 n/a

Urban tree benefi ts (2000)

Estimated number of trees n/a 28,200,000 83,400,000 87,600,000

Carbon

Carbon stored (metric tons) n/a 5,400,000 15,900,000 16,700,000

Carbon stored ($) n/a $123,100,000 $362,500,000 $380,800,000

Carbon sequestered (metric tons/year) n/a 178,000 525,000 551,000

Carbon sequestered ($/year) n/a $4,058,000 $11,970,000 $12,563,000

Pollution

CO removed (metric tons/year) n/a 165 488 512

CO removed ($/year) n/a $232,400 $686,000 $720,700

NO2 removed (metric tons/year) n/a 309 913 959

NO2 removed ($/year) n/a $3,062,600 $9,042,000 $9,499,600

O3 removed (metric tons/year) n/a 2,822 8,332 8,754

O3 removed ($/year) n/a $27,957,000 $82,539,000 $86,717,000

SO2 removed (metric tons/year) n/a 201 593 623

SO2 removed ($/year) n/a $487,300 $1,438,600 $1,511,400

PM10 removed (metric tons/year) n/a 1,731 5,112 5,370

PM10 removed ($/year) n/a $11,451,200 $33,808,600 $35,519,700

Total pollution removal (metric tons/year) n/a 5,230 15,440 16,220

Total pollution removal ($/year) n/a $43,200,000 $127,500,000 $134,000,000

Table AR-1.—Statewide summary of population, area, population density, tree canopy and impervious surface land 

cover, and urban tree benefi ts in urban, community, and urban or community areas.
GTR-NRS-59 Arkansas 13

Figure AR-1.—Urban or community land 

in 2000; urban area relative to community 

boundaries. Figure AR-2.—2000 population within 

county subdivision boundaries.

Human Population Characteristics 

and Trends 

The population in Arkansas increased 13.7 percent, 

from 2,350,725 in 1990 to 2,673,400 in 2000 (Table 

AR-1). In Arkansas, 52.5 percent of the State’s population 

is in urban areas (Fig. AR-1), and 63.9 percent of the 

population is within communities (Fig. AR-2).

Urban and Community Land 

Urban land comprises 1.7 percent of the land area of 

Arkansas, while lands within communities make up 

4.4 percent of the State (Fig. AR-1). Between 1990 and 

2000, urban area increased 19.7 percent, while community 

land increased from 3.6 to 4.4 percent (Table AR-1). 

Urban area in Arkansas is projected to increase to 

5.8 percent by 2050, based on average urban growth 

pattern of the 1990s (Nowak and Walton 2005). Both 

urban land (attaining minimum population density) and 

community land (political boundaries) increased from 

1990 to 2000. The percentages are calculated using the 

total (water and land) area of the geopolitical units derived 

from U.S. Census cartographic boundary data.Percent 

urban land varied across the State (Fig. AR-3; 

Tables AR-2 through 4).

Figure AR-3.—Percent of county 

subdivision area classifi ed as urban land 

in 2000.

Total Population

0 - 3,408

3,409 - 12,403

12,404 - 31,426

31,427 - 73,974

73,975 - 209,351

Percent

0% - 3.7%

3.8% - 12.4%

12.5% - 25.8%

25.9% - 44.3%

44.4% - 77.5%
14 GTR-NRS-59 Arkansas

Tree Canopy Cover Characteristics

Tree canopy cover in Arkansas averages 45.7 percent 

(Fig. AR-4), with 99.0 percent total green space, 

46.2 percent canopy green space, and 22,989.4 m2

 of 

canopy cover per capita. Average tree cover in urban 

areas in Arkansas was 25.4 percent, with 80.0 percent 

total green space, 31.8 percent canopy green space, and 

421.8 m2

 of canopy cover per capita. Within community 

lands in Arkansas, average tree cover was 29.8 percent, 

with 88.8 percent total green space, 33.6 percent canopy 

green space, and 1,023.0 m2

 of canopy cover per capita 

(Table AR-1). Tree canopy cover, canopy green space, 

and tree cover per capita varied among communities, 

county subdivisions, and counties (Fig. AR-5 through 6; 

Tables AR-5 through 7).

Figure AR-4.—Percentage tree canopy 

cover.

Figure AR-6.—Percentage tree canopy 

green space in county subdivisions.

Figure AR-5.—Percentage tree canopy 

cover within county subdivisions.

Percent

0.8% - 17.7%

17.8% - 34.4%

34.5% - 50.7%

50.8% - 66%

66.1% - 87.4%

Percent

0.8% - 17.7%

17.8% - 34.4%

34.5% - 50.7%

50.8% - 66%

66.1% - 87.4%
GTR-NRS-59 Arkansas 15

Figure AR-7.—Percentage impervious 

surface cover.

Figure AR-8.—Percentage impervious 

surface cover within county subdivisions.

Impervious Surface Cover Characteristics

Average impervious surface cover in Arkansas is 1.0 percent of the land area 

(Fig. AR-7), with 509.1 m2

 of impervious surface cover per capita. Average 

impervious surface cover in urban areas was 20.0 percent, with 332.1 m2

 of 

impervious surface cover per capita. Within community lands in Arkansas, 

average impervious surface cover was 11.2 percent with 385.9 m2

 of impervious 

surface cover per capita (Table AR-1). Impervious surface cover varied across 

the State (Fig. AR-8; Tables AR-5 through 7).

Percent

0% - 0.7%

0.8% - 1.9%

2% - 4.7%

4.8% - 10%

10.1% - 25.3%
16 GTR-NRS-59 Arkansas

Figure AR-9.—Classifi ed land cover.

Figure AR-10.—Relative comparisons 

of tree cover for county subdivisions.

Classifi ed Land-cover Characteristics

Arkansas’ land cover is dominated by forest land (Fig. AR-9). The characteristics 

as a percent of the total land area in Arkansas are (Tables AR-8 through 10):

• Forested – 47.1 percent

• Agricultural – 42.7 percent

• Developed – 5.8 percent

• Scrub/Shrub – 2.9 percent

• Grassland – 1.3 percent

• Wetland – 0.1 percent

• Barren – 0.1 percent

Relative Comparisons of Tree Cover

Out of the 519 Arkansas communities, 13 received a rating of excellent and 

224 received a rating of poor (Table AR-12).Of the 1,330 county subdivisions, 

62 had a rating of excellent and 308 were rated poor (Fig. AR-10, Table AR-13); 

and out of 75 counties, 11 were given a rating of excellent and four were given a 

rating of poor (Table AR-14). Variability of assessment scores is a product of the 

difference in land-cover distributions and the percentage of canopy cover within 

the population density classes and mapping zones (Fig. AR-10; Tables AR-11 

through 14). 
GTR-NRS-59 Arkansas 17

Priority Areas for Tree Planting

Priority areas for planting tend to be highest in more urbanized areas due to 

higher population density (Fig. AR-11; Tables AR-15 through 17). These index 

values can also be produced using high resolution cover data to determine local 

planting priority areas (e.g., neighborhoods). 

Urban Tree Benefi ts

The following forest attributes are estimated for the urban or community land 

in Arkansas (Table AR-1). These are rough estimates of values. More localized 

data are needed for more precise estimates, but these values reveal fi rst-order 

approximations. 

y 87.6 million trees

y 16.7 million metric tons of C stored ($380.8 million value)

y 551,000 metric tons/year of C sequestered ($12.6 million value)

y 16,220 metric tons/year total pollution removal ($134.0 million value)

▪ 512 metric tons/year of CO removed ($720,700 value)

▪ 959 metric tons/year NO2

 removed ($9.5 million value)

▪ 8,754 metric tons/year of O3

 removed ($86.7 million value)

▪ 623 metric tons/year of SO2

 removed ($1.5 million value) 

▪ 5,370 metric tons/year of PM10 removed ($35.5 million value)

Figure AR-11.—Planting priority index for 

county subdivisions. The higher the index 

value, the greater priority for planting.

Index Value

0.0 - 31.8

31.9 - 39.1

39.2 - 47.1

47.2 - 55.3

55.4 - 100.0
18 GTR-NRS-59 Arkansas

Summary

The data presented in this report provide a better understanding of Arkansas’ 

urban and community forests. This information can be used to advance urban 

and community forest policy and management that could improve environmental 

quality and human health throughout the State. 

These data establish a baseline to assess future change and can be used to 

understand:

• Extent of the urban and community forest resource

• Variations in the resource across the State

• Magnitude and value of the urban and community forest resource

• Urban growth in Arkansas

• Implications of policy decisions related to urban sprawl and urban and 

community forest management
GTR-NRS-59 Louisiana 19

Statewide Summary

Urban or community land in Louisiana comprises about 6.9 percent of the state 

land area in 2000, an increase from 6.2 percent in 1990. Statewide tree canopy 

cover averages 39.0 percent and tree cover in urban or community areas is about 

28.3 percent, with 14.7 percent impervious surface cover and 33.2 percent of the 

total green space covered by tree canopy cover. Statewide, urban or community 

land in Louisiana has an estimated 102.5 million trees, which store about 

19.6 million metric tons of carbon ($446.9 million), and annually remove about 

645,000 metric tons of carbon ($14.7 million) and 21,890 metric tons of air 

pollution ($177.7 million) (Table LA-1).

Tables LA-2 through LA-17 are not printed in this report but are available on the 

CD located on the inside back cover and at http://nrs.fs.fed.us/data/urban.

LOUISIANA’S URBAN 

AND COMMUNITY FORESTS
20 GTR-NRS-59 Louisiana

a Urban land is based on population density and was delimited using the United States Census defi nitions of urbanized areas and urban clusters. b Community 

land is based on jurisdictional or political boundaries of communities based on United States Census defi nitions of incorporated or census designated places. c

 Urban or communities is land that is urban, community, or both. Communities may include all, some, or no urban land within their boundaries. d Canopy green 

space is the tree canopy cover divided by total green space. e Total green space (TGS) is total area – impervious surface cover – water. f Available green space 

(AGS) is total green space – tree canopy cover (if the calculated value is less than 0, then value set at 0). 

Louisiana Statewide Urban a Community b

 Urban or

Community c

Population

2000 4,468,976 3,245,665 2,998,842 n/a

1990 4,219,973 2,871,759 2,866,592 n/a

% Change (1990-2000) 5.9 13.0 4.6 n/a

% Total population (2000) 100.0 72.6 67.1 n/a

Total area 

km2 (2000) 134,264.2 4,316.6 6,977.8 8,443.6

km2 (1990) 134,264.2 3,941.3 6,508.1 7,852.2

% Change (1990-2000) 0.0 9.5 7.2 7.5

Land area 

km2 (2000) 110,780.2 4,256.1 6,156.0 7,598.3

% Land area (2000) 100.0 3.8 5.6 6.9

km2 (1990) 110,780.2 3,889.2 5,529.1 6,851.8

% Land area (1990) 100.0 3.5 5.0 6.2

% Change (1990-2000) 0.0 9.4 11.3 10.9

Population density 

 (people/land area km2)

2000 40.3 762.6 487.1 n/a

1990 38.1 738.4 518.5 n/a

% Change (1990-2000) 5.9 3.3 -6.0 n/a

Tree canopy cover (2000)

km2 43,186.3 1,104.8 1,732.1 2,149.7

% Land area 39.0 26.0 28.1 28.3

Per capita (m2/person) 9,663.6 340.4 577.6 n/a

% Canopy green space d 39.7 33.2 33.3 33.2

Total green space (2000) e km2 108,706.0 3,326.4 5,195.7 6,478.6

% Land area 98.1 78.2 84.4 85.3

Available green space (2000) f km2 65,530.9 2,224.8 3,466.9 4,332.6

% Land area 59.2 52.3 56.3 57.0

Impervious surface cover 

 (2000)

km2 2,074.5 929.6 960.2 1,119.6

% Land area 1.9 21.8 15.6 14.7

Per capita (m2/person) 464.2 286.4 320.2 n/a

Urban tree benefi ts (2000)

Estimated number of trees n/a 52,700,000 82,600,000 102,500,000

Carbon

Carbon stored (metric tons) n/a 10,100,000 15,800,000 19,600,000

Carbon stored ($) n/a $230,300,000 $360,200,000 $446,900,000

Carbon sequestered (metric tons/year) n/a 331,000 520,000 645,000

Carbon sequestered ($/year) n/a $7,547,000 $11,856,000 $14,706,000

Pollution

CO removed (metric tons/year) n/a 430 674 836

CO removed ($/year) n/a $604,700 $948,100 $1,176,600

NO2 removed (metric tons/year) n/a 937 1,469 1,823

NO2 removed ($/year) n/a $9,281,700 $14,552,200 $18,060,700

O3 removed (metric tons/year) n/a 5,587 8,760 10,872

O3 removed ($/year) n/a $55,346,000 $86,774,000 $107,694,000

SO2 removed (metric tons/year) n/a 549 860 1,068

SO2 removed ($/year) n/a $1,330,600 $2,086,200 $2,589,200

PM10 removed (metric tons/year) n/a 3,747 5,875 7,291

PM10 removed ($/year) n/a $24,782,500 $38,855,000 $48,222,700

Total pollution removal (metric tons/year) n/a 11,250 17,640 21,890

Total pollution removal ($/year) n/a $91,300,000 $143,200,000 $177,700,000

Table LA-1.—Statewide summary of population, area, population density, tree canopy and impervious surface land 

cover, and urban tree benefi ts in urban, community, and urban or community areas.
GTR-NRS-59 Louisiana 21

Figure LA-3.—Percent of county subdivision area 

classifi ed as urban land in 2000.

Human Population Characteristics 

and Trends 

The population in Louisiana increased 5.9 percent, from 

4,219,973 in 1990 to 4,468,976 in 2000 (Table LA-1). 

In Louisiana, 72.6 percent of the State’s population 

is in urban areas (Fig. LA-1), and 67.1 percent of the 

population is within communities (Fig. LA-2).

Urban and Community Land 

Urban land comprises 3.8 percent of the land area of 

Louisiana, while lands within communities make up 

5.6 percent of the State (Fig. LA-1). Between 1990 and 

2000, urban area increased 9.4 percent, while community 

land increased from 5.0 to 5.6 percent (Table LA-1). 

Urban area in Louisiana is projected to increase to 

11.1 percent by 2050, based on average urban growth 

pattern of the 1990s (Nowak and Walton 2005). Both 

urban land (attaining minimum population density) and 

community land (political boundaries) increased from 

1990 to 2000. The percentages are calculated using 

the total (water and land) area of the geopolitical units 

derived from U.S. Census cartographic boundary data. 

Percent urban land varied across the State (Fig. LA-3; 

Tables LA-2 through 4).

Figure LA-2.—2000 population within county 

subdivision boundaries.

Figure LA-1.—Urban or community land in 2000; 

urban area relative to community boundaries.

Percent

0% - 5.3%

5.4% - 18.8%

18.9% - 42.9%

43% - 75.3%

75.4% - 100%
22 GTR-NRS-59 Louisiana

Figure LA-4.—Percentage tree canopy cover. Figure LA-5.—Percentage tree canopy cover within 

county subdivisions.

Figure LA-6.—Percentage tree canopy green space in 

county subdivisions.

Tree Canopy Cover Characteristics

Tree canopy cover in Louisiana averages 39.0 percent 

(Fig. LA-4), with 98.1 percent total green space, 

39.7 percent canopy green space, and 9,663.6 m2

of canopy cover per capita. Average tree cover in 

urban areas in Louisiana was 26.0 percent, with 

78.2 percent total green space, 33.2 percent canopy 

green space, and 340.4 m2

 of canopy cover per capita. 

Within community lands in Louisiana, average tree 

cover was 28.1 percent, with 84.4 percent total green 

space, 33.3 percent canopy green space, and 577.6 m2

of canopy cover per capita (Table LA-1). Tree canopy 

cover, canopy green space, and tree cover per capita 

varied among communities, county subdivisions, 

and counties (Fig. LA-5 through 6; Tables LA-5 

through 7).
GTR-NRS-59 Louisiana 23

Figure LA-7.—Percentage impervious surface cover. Figure LA-8.—Percentage impervious surface cover 

within county subdivisions.

Impervious Surface Cover Characteristics

Average impervious surface cover in Louisiana is 1.9 percent of the land area 

(Fig. LA-7), with 464.2 m2

 of impervious surface cover per capita. Average 

impervious surface cover in urban areas was 21.8 percent, with 286.4 m2

 of 

impervious surface cover per capita. Within community lands in Louisiana, 

average impervious surface cover was 15.6 percent with 320.2 m2

 of impervious 

surface cover per capita (Table LA-1). Impervious surface cover varied across 

the State (Fig. LA-8; Tables LA-5 through 7).
24 GTR-NRS-59 Louisiana

Figure LA-9.—Classifi ed land cover.

Figure LA-10.—Relative comparisons of tree cover for 

county subdivisions.

Classifi ed Land-cover Characteristics

Louisiana’s land cover is dominated by agricultural land (Fig. LA-9). The 

characteristics as a percent of the total land area in Louisiana are (Tables LA-8 

through 10):

• Agricultural – 48.3 percent

• Forested – 23.4 percent

• Wetland – 11.5 percent

• Scrub/Shrub – 7.8 percent

• Developed – 6.9 percent

• Grassland – 1.7 percent

• Barren – 0.3 percent

Relative Comparisons of Tree Cover

Out of the 398 Louisiana communities, 12 received a rating of excellent and 

132 received a rating of poor (Table LA-12). Of the 597 county subdivisions, 

24 had a rating of excellent and 180 were rated poor (Fig. LA-10, Table LA-13); 

and out of 64 counties, nine were given a rating of excellent and nine were given 

a rating of poor (Table LA-14). Variability of assessment scores is a product of 

the difference in land-cover distributions and the percentage of canopy cover 

within the population density classes and mapping zones (Fig. LA-10; 

Tables LA-11 through 14). 
GTR-NRS-59 Louisiana 25

Figure LA-11.—Planting priority index for county 

subdivisions. The higher the index value, the greater 

priority for planting.

Priority Areas for Tree Planting

Priority areas for planting tend to be highest in more urbanized areas due to 

higher population density (Fig. LA-11; Tables LA-15 through 17). These index 

values can also be produced using high resolution cover data to determine local 

planting priority areas (e.g., neighborhoods). 

Urban Tree Benefi ts

The following forest attributes are estimated for the urban or community land 

in Louisiana (Table LA-1). These are rough estimates of values. More localized 

data are needed for more precise estimates, but these values reveal fi rst-order 

approximations. 

y 102.5 million trees

y 19.6 million metric tons of C stored ($446.9 million value)

y 645,000 metric tons/year of C sequestered ($14.7 million value)

y 21,890 metric tons/year total pollution removal ($177.7 million value)

▪ 836 metric tons/year of CO removed ($1.2 million value)

▪ 1,823 metric tons/year NO2

 removed ($18.1 million value)

▪ 10,872 metric tons/year of O3

 removed ($107.7 million value)

▪ 1,068 metric tons/year of SO2

 removed ($2.6 million value) 

▪ 7,291 metric tons/year of PM10 removed ($48.2 million value).
26 GTR-NRS-59 Louisiana

Summary

The data presented in this report provide a better understanding of Louisiana’s 

urban and community forests. This information can be used to advance urban 

and community forest policy and management that could improve environmental 

quality and human health throughout the State. 

These data establish a baseline to assess future change and can be used to 

understand:

• Extent of the urban and community forest resource

• Variations in the resource across the State

• Magnitude and value of the urban and community forest resource

• Urban growth in Louisiana

• Implications of policy decisions related to urban sprawl and urban and 

community forest management
GTR-NRS-59 Oklahoma 27

Statewide Summary

Urban or community land in Oklahoma comprises about 6.8 percent of the state 

land area in 2000, an increase from 5.2 percent in 1990. Statewide tree canopy 

cover averages 16.5 percent and tree cover in urban or community areas is about 

19.3 percent, with 8.3 percent impervious surface cover and 21.0 percent of the 

total green space covered by tree canopy cover. Statewide, urban or community 

land in Oklahoma has an estimated 111.5 million trees, which store about 

21.3 million metric tons of carbon ($485.6 million), and annually remove about 

702,000 metric tons of carbon ($16.0 million) and 22,520 metric tons of air 

pollution ($189.2 million) (Table OK-1).

Tables OK-2 through OK-17 are not printed in this report but are available on the 

CD located on the inside back cover and at http://nrs.fs.fed.us/data/urban.

OKLAHOMA’S URBAN 

AND COMMUNITY FORESTS
28 GTR-NRS-59 Oklahoma

a Urban land is based on population density and was delimited using the United States Census defi nitions of urbanized areas and urban clusters. b Community 

land is based on jurisdictional or political boundaries of communities based on United States Census defi nitions of incorporated or census designated places. c

 Urban or communities is land that is urban, community, or both. Communities may include all, some, or no urban land within their boundaries. d Canopy green 

space is the tree canopy cover divided by total green space. e Total green space (TGS) is total area – impervious surface cover – water. f Available green space 

(AGS) is total green space – tree canopy cover (if the calculated value is less than 0, then value set at 0). 

Oklahoma Statewide Urban a Community b

 Urban or

Community c

Population

2000 3,450,654 2,254,563 2,661,545 n/a

1990 3,145,585 2,130,139 2,397,656 n/a

% Change (1990-2000) 9.7 5.8 11.0 n/a

% Total population (2000) 100.0 65.3 77.1 n/a

Total area 

km2 (2000) 181,035.5 3,007.1 12,119.4 12,122.6

km2 (1990) 181,035.5 2,703.5 9,208.9 9,493.8

% Change (1990-2000) 0.0 11.2 31.6 30.9

Land area 

km2 (2000) 177,398.7 2,977.5 11,814.1 12,431.0

% Land area (2000) 100.0 1.7 6.7 6.8

km2 (1990) 177,398.7 2,684.4 8,956.9 9,239.2

% Land area (1990) 100.0 1.5 5.0 5.2

% Change (1990-2000) 0.0 10.9 31.9 31.2

Population density 

 (people/land area km2)

2000 19.5 757.2 225.3 n/a

1990 17.7 793.5 267.7 n/a

% Change (1990-2000) 9.7 -4.6 -15.8 n/a

Tree canopy cover (2000)

km2 29,306.8 249.1 2,298.2 2,338.5

% Land area 16.5 8.4 19.5 19.3

Per capita (m2/person) 8,493.1 110.5 863.5 n/a

% Canopy green space d 16.7 11.1 21.2 21.0

Total green space (2000) e km2 175,818.0 2,249.7 10,827.6 11,110.9

% Land area 99.1 75.6 91.6 91.7

Available green space (2000) f km2 146,512.0 2,000.6 8,529.3 8,772.5

% Land area 82.6 67.2 72.2 72.4

Impervious surface cover 

 (2000)

km2 1,580.5 727.8 986.5 1,011.6

% Land area 0.9 24.4 8.4 8.3

Per capita (m2/person) 458.0 322.8 370.7 n/a

Urban tree benefi ts (2000)

Estimated number of trees n/a 11,900,000 109,600,000 111,500,000

Carbon

Carbon stored (metric tons) n/a 2,300,000 20,900,000 21,300,000

Carbon stored ($) n/a $52,400,000 $476,500,000 $485,600,000

Carbon sequestered (metric tons/year) n/a 75,000 689,000 702,000

Carbon sequestered ($/year) n/a $1,710,000 $15,709,000 $16,006,000

Pollution

CO removed (metric tons/year) n/a 33 302 307

CO removed ($/year) n/a $46,000 $424,400 $431,800

NO2 removed (metric tons/year) n/a 121 1,120 1,139

NO2 removed ($/year) n/a $1,202,300 $11,091,500 $11,285,600

O3 removed (metric tons/year) n/a 1,401 12,922 13,148

O3 removed ($/year) n/a $13,875,000 $128,002,000 $130,241,000

SO2 removed (metric tons/year) n/a 132 1,217 1,238

SO2 removed ($/year) n/a $319,900 $2,951,400 $3,003,000

PM10 removed (metric tons/year) n/a 712 6,569 6,684

PM10 removed ($/year) n/a $4,709,900 $43,450,000 $44,210,200

Total pollution removal (metric tons/year) n/a 2,400 22,130 22,520

Total pollution removal ($/year) n/a $20,200,000 $185,900,000 $189,200,000

Table OK-1.—Statewide summary of population, area, population density, tree canopy and impervious surface land 

cover, and urban tree benefi ts in urban, community, and urban or community areas.
GTR-NRS-59 Oklahoma 29

Figure OK-1.—Urban or community land in 2000; 

urban area relative to community boundaries.

Figure OK-2.—2000 population within county 

subdivision boundaries.

Figure OK-3.—Percent of county subdivision area 

classifi ed as urban land in 2000.

Human Population Characteristics 

and Trends 

The population in Oklahoma increased 9.7 percent, from 

3,145,585 in 1990 to 3,450,654 in 2000 (Table OK-1). 

In Oklahoma, 65.3 percent of the State’s population 

is in urban areas (Fig. OK-1), and 77.1 percent of the 

population is within communities (Fig. OK-2).

Urban and Community Land 

Urban land comprises 1.7 percent of the land area of 

Oklahoma, while lands within communities make up 

6.7 percent of the State (Fig. OK-1). Between 1990 

and 2000, urban area increased 10.9 percent, while 

community land increased from 5.0 to 6.7 percent 

(Table OK-1). Urban area in Oklahoma is projected to 

increase to 4.7 percent by 2050, based on average urban 

growth pattern of the 1990s (Nowak and Walton 2005). 

Both urban land (attaining minimum population density) 

and community land (political boundaries) increased 

from 1990 to 2000. The percentages are calculated using 

the total (water and land) area of the geopolitical units 

derived from U.S. Census cartographic boundary data. 

Percent urban land varied across the State (Fig. OK-3; 

Tables OK-2 through 4).
30 GTR-NRS-59 Oklahoma

Figure OK-4.—Percentage tree canopy cover.

Figure OK-5.—Percentage tree canopy cover within 

county subdivisions.

Figure OK-6.—Percentage tree canopy green space 

in county subdivisions.

Tree Canopy Cover Characteristics

Tree canopy cover in Oklahoma averages 16.5 percent 

(Fig. OK-4), with 99.1 percent total green space, 

16.7 percent canopy green space, and 8,493.1 m2

 of 

canopy cover per capita. Average tree cover in urban 

areas in Oklahoma was 8.4 percent, with 75.6 percent 

total green space, 11.1 percent canopy green space, 

and 110.5 m2

 of canopy cover per capita. Within 

community lands in Oklahoma, average tree cover 

was 19.5 percent, with 91.6 percent total green space, 

21.2 percent canopy green space, and 863.5 m2

 of 

canopy cover per capita (Table OK-1). Tree canopy 

cover, canopy green space, and tree cover per capita 

varied among communities, county subdivisions, 

and counties (Fig. OK-5 through 6; Tables OK-5 

through 7).
GTR-NRS-59 Oklahoma 31

Figure OK-7.—Percentage impervious surface cover.

Figure OK-8.—Percentage impervious surface cover 

within county subdivisions.

Impervious Surface Cover Characteristics

Average impervious surface cover in Oklahoma is 0.9 percent of the land area 

(Fig. OK-7), with 458.0 m2

 of impervious surface cover per capita. Average 

impervious surface cover in urban areas was 24.4 percent, with 322.8 m2

 of 

impervious surface cover per capita. Within community lands in Oklahoma, 

average impervious surface cover was 8.4 percent with 370.7 m2

 of impervious 

surface cover per capita (Table OK-1). Impervious surface cover varied across 

the State (Fig. OK-8; Tables OK-5 through 7).
32 GTR-NRS-59 Oklahoma

Figure OK-9.—Classifi ed land cover.

Figure OK-10.—Relative comparisons of tree cover for 

county subdivisions.

Classifi ed Land-cover Characteristics

Oklahoma’s land cover is dominated by grassland (Fig. OK-9). The 

characteristics as a percent of the total land area in Oklahoma are (Tables OK-8 

through 10):

• Grassland – 37.2 percent

• Agricultural – 30.4 percent

• Forested – 22.0 percent

• Developed – 5.7 percent 

• Scrub/Shrub – 4.3 percent

• Barren – 0.2 percent

• Wetland – 0.1 percent

Relative Comparisons of Tree Cover

Out of the 691 Oklahoma communities, 19 received a rating of excellent and 

416 received a rating of poor (Table OK-12). Of the 302 county subdivisions, 

six had a rating of excellent and 153 were rated poor (Fig. OK-10, Table OK-13); 

and out of 77 counties, four were given a rating of excellent and 36 were given a 

rating of poor (Table OK-14). Variability of assessment scores is a product of the 

difference in land-cover distributions and the percentage of canopy cover within 

the population density classes and mapping zones (Fig. OK-10; Tables OK-11 

through 14). 
GTR-NRS-59 Oklahoma 33

Figure OK-11.—Planting priority index for county 

subdivisions. The higher the index value, the greater 

priority for planting.

Priority Areas for Tree Planting

Priority areas for planting tend to be highest in more urbanized areas due to 

higher population density (Fig. OK-11; Tables OK-15 through 17). These index 

values can also be produced using high resolution cover data to determine local 

planting priority areas (e.g., neighborhoods). 

Urban Tree Benefi ts

The following forest attributes are estimated for the urban or community land in 

Oklahoma (Table OK-1). These are rough estimates of values. More localized 

data are needed for more precise estimates, but these values reveal fi rst-order 

approximations. 

y 111.5 million trees

y 21.3 million metric tons of C stored ($485.6 million value)

y 702,000 metric tons/year of C sequestered ($16.0 million value)

y 22,520 metric tons/year total pollution removal ($189.2 million value)

▪ 307 metric tons/year of CO removed ($431,800 value)

▪ 1,139 metric tons/year NO2

 removed ($11.3 million value)

▪ 13,148 metric tons/year of O3

 removed ($130.2 million value)

▪ 1,238 metric tons/year of SO2

 removed ($3.0 million value) 

▪ 6,684 metric tons/year of PM10 removed ($44.2 million value)
34 GTR-NRS-59 Oklahoma

Summary

The data presented in this report provide a better understanding of Oklahoma’s 

urban and community forests. This information can be used to advance urban 

and community forest policy and management that could improve environmental 

quality and human health throughout the State. 

These data establish a baseline to assess future change and can be used to 

understand:

• Extent of the urban and community forest resource

• Variations in the resource across the State

• Magnitude and value of the urban and community forest resource

• Urban growth in Oklahoma

• Implications of policy decisions related to urban sprawl and urban and 

community forest management
GTR-NRS-59 Texas 35

Statewide Summary

Urban or community land in Texas comprises about 5.0 percent of the state 

land area in 2000, an increase from 4.0 percent in 1990. Statewide tree canopy 

cover averages 11.9 percent and tree cover in urban or community areas is about 

14.8 percent, with 17.4 percent impervious surface cover and 17.9 percent of the 

total green space covered by tree canopy cover. Statewide, urban or community 

land in Texas has an estimated 237.5 million trees, which store about 45.3 million 

metric tons of carbon ($1.0 billion), and annually remove about 1.5 million 

metric tons of carbon ($34.1 million) and 46,090 metric tons of air pollution 

($374.4 million) (Table TX-1).

Tables TX-2 through TX-17 are not printed in this report but are available on the 

CD located on the inside back cover and at http://nrs.fs.fed.us/data/urban.

TEXAS’ URBAN AND

COMMUNITY FORESTS
36 GTR-NRS-59 Texas

a Urban land is based on population density and was delimited using the United States Census defi nitions of urbanized areas and urban clusters. b Community 

land is based on jurisdictional or political boundaries of communities based on United States Census defi nitions of incorporated or census designated places. c

 Urban or communities is land that is urban, community, or both. Communities may include all, some, or no urban land within their boundaries. d Canopy green 

space is the tree canopy cover divided by total green space. e Total green space (TGS) is total area – impervious surface cover – water. f Available green space 

(AGS) is total green space – tree canopy cover (if the calculated value is less than 0, then value set at 0). 

Texas Statewide Urban a Community b

 Urban or

Community c

Population

2000 20,851,820 17,204,281 16,633,056 n/a

1990 16,986,510 13,634,517 13,452,394 n/a

% Change (1990-2000) 22.8 26.2 23.6 n/a

% Total population (2000) 100.0 82.5 79.8 n/a

Total area 

km2 (2000) 695,621.1 18,545.0 31,405.1 34,857.2

km2 (1990) 695,621.1 15,314.9 25,288.5 28,063.1

% Change (1990-2000) 0.0 21.1 24.2 24.2

Land area 

km2 (2000) 678,431.9 18,386.7 30,257.8 33,668.9

% Land area (2000) 100.0 2.7 4.5 5.0

km2 (1990) 678,431.9 15,208.4 24,317.1 27,067.2

% Land area (1990) 100.0 2.2 3.6 4.0

% Change (1990-2000) 0.0 20.9 24.4 24.4

Population density 

 (people/land area km2)

2000 30.7 935.7 549.7 n/a

1990 25.0 896.5 553.2 n/a

% Change (1990-2000) 22.8 4.4 -0.6 n/a

Tree canopy cover (2000)

km2 80,422.7 2,669.7 4,345.0 4,980.7

% Land area 11.9 14.5 14.4 14.8

Per capita (m2/person) 3,856.9 155.2 261.2 n/a

% Canopy green space d 12.0 19.8 17.5 17.9

Total green space (2000) e km2 669,510.0 13,487.0 24,879.8 27,820.3

% Land area 98.7 73.4 82.2 82.6

Available green space (2000) f km2 589,150.0 10,865.6 20,577.8 22,890.2

% Land area 86.8 59.1 68.0 68.0

Impervious surface cover 

 (2000)

km2 8,922.2 4,899.7 5,378.0 5,848.6

% Land area 1.3 26.6 17.8 17.4

Per capita (m2/person) 427.9 284.8 323.3 n/a

Urban tree benefi ts (2000)

Estimated number of trees n/a 127,300,000 207,200,000 237,500,000

Carbon

Carbon stored (metric tons) n/a 24,300,000 39,500,000 45,300,000

Carbon stored ($) n/a $554,000,000 $900,600,000 $1,032,800,000

Carbon sequestered (metric tons/year) n/a 801,000 1,304,000 1,494,000

Carbon sequestered ($/year) n/a $18,263,000 $29,731,000 $34,063,000

Pollution

CO removed (metric tons/year) n/a 740 1,205 1,382

CO removed ($/year) n/a $1,041,900 $1,695,700 $1,943,800

NO2 removed (metric tons/year) n/a 2,997 4,878 5,592

NO2 removed ($/year) n/a $29,692,200 $48,325,400 $55,395,800

O3 removed (metric tons/year) n/a 11,580 18,848 21,605

O3 removed ($/year) n/a $114,715,000 $186,703,000 $214,020,000

SO2 removed (metric tons/year) n/a 1,637 2,665 3,055

SO2 removed ($/year) n/a $3,970,900 $6,462,800 $7,408,400

PM10 removed (metric tons/year) n/a 7,749 12,611 14,457

PM10 removed ($/year) n/a $51,250,100 $83,411,900 $95,615,700

Total pollution removal (metric tons/year) n/a 24,700 40,210 46,090

Total pollution removal ($/year) n/a $200,700,000 $326,600,000 $374,400,000

Table TX-1.—Statewide summary of population, area, population density, tree canopy and impervious surface land 

cover, and urban tree benefi ts in urban, community, and urban or community areas.
GTR-NRS-59 Texas 37

Figure TX-1.—Urban or community land in 2000; 

urban area relative to community boundaries.

Figure TX-2.—2000 population within county 

subdivision boundaries.

Figure TX-3.—Percent of county subdivision area 

classifi ed as urban land in 2000.

Human Population Characteristics 

and Trends 

The population in Texas increased 22.8 percent, from 

16,986,510 in 1990 to 20,851,820 in 2000 (Table 

TX-1). In Texas, 82.5 percent of the State’s population 

is in urban areas (Fig. TX-1), and 79.8 percent of the 

population is within communities (Fig. TX-2).

Urban and Community Land 

Urban land comprises 2.7 percent of the land area 

of Texas, while lands within communities make up 

4.5 percent of the State (Fig. TX-1). Between 1990 

and 2000, urban area increased 20.9 percent, while 

community land increased from 3.6 to 4.5 percent 

(Table TX-1). Urban area in Texas is projected to 

increase to 7.0 percent by 2050, based on average urban 

growth pattern of the 1990s (Nowak and Walton 2005). 

Both urban land (attaining minimum population density) 

and community land (political boundaries) increased 

from 1990 to 2000. The percentages are calculated using 

the total (water and land) area of the geopolitical units 

derived from U.S. Census cartographic boundary data. 

Percent urban land varied across the State (Fig. TX-3; 

Tables TX-2 through 4).
38 GTR-NRS-59 Texas

Figure TX-4.—Percentage tree canopy cover.

Figure TX-5.—Percentage tree canopy cover within 

county subdivisions.

Figure TX-6.—Percentage tree canopy green space in 

county subdivisions.

Tree Canopy Cover Characteristics

Tree canopy cover in Texas averages 11.9 percent 

(Fig. TX-4), with 98.7 percent total green space, 

12.0 percent canopy green space, and 3,856.9 m2

 of 

canopy cover per capita. Average tree cover in urban 

areas in Texas was 14.5 percent, with 73.4 percent 

total green space, 19.8 percent canopy green space, 

and 155.2 m2

 of canopy cover per capita. Within 

community lands in Texas, average tree cover was 

14.4 percent, with 82.2 percent total green space, 

17.5 percent canopy green space, and 261.2 m2

 of 

canopy cover per capita (Table TX-1). Tree canopy 

cover, canopy green space, and tree cover per capita 

varied among communities, county subdivisions, 

and counties (Fig. TX-5 through 6; Tables TX-5 

through 7).
GTR-NRS-59 Texas 39

Figure TX-7.—Percentage impervious surface cover.

Figure TX-8.—Percentage impervious surface cover 

within county subdivisions.

Impervious Surface Cover Characteristics

Average impervious surface cover in Texas is 1.3 percent of the land area 

(Fig. TX-7), with 427.9 m2

 of impervious surface cover per capita. Average 

impervious surface cover in urban areas was 26.6 percent, with 284.8 m2

 of 

impervious surface cover per capita. Within community lands in Texas, average 

impervious surface cover was 17.8 percent with 323.3 m2

 of impervious surface 

cover per capita (Table TX-1). Impervious surface cover varied across the State 

(Fig. TX-8; Tables TX-5 through 7).
40 GTR-NRS-59 Texas

Figure TX-9.—Classifi ed land cover.

Figure TX-10.—Relative comparisons of tree cover for 

county subdivisions.

Classifi ed Land-cover Characteristics

Texas’ land cover is dominated by scrub/shrub land (Fig. TX-9). The 

characteristics as a percent of the total land area in Texas are (Tables TX-8 

through 10):

• Scrub/Shrub – 40.7 percent

• Agricultural – 23.8 percent

• Grassland – 18.1 percent

• Forested – 10.7 percent

• Developed – 5.3 percent

• Wetland – 0.8 percent

• Barren – 0.5 percent

Relative Comparisons of Tree Cover

Out of the 1,510 Texas communities, 52 received a rating of excellent and 

1,033 received a rating of poor (Table TX-12). Of the 860 county subdivisions, 

22 had a rating of excellent and 458 were rated poor (Fig. TX-10, Table TX-13); 

and out of 254 counties, 12 were given a rating of excellent and 119 were given a 

rating of poor (Table TX-14). Variability of assessment scores is a product of the 

difference in land-cover distributions and the percentage of canopy cover within 

the population density classes and mapping zones (Fig. TX-10; Tables TX-11 

through 14). 
GTR-NRS-59 Texas 41

Priority Areas for Tree Planting

Priority areas for planting tend to be highest in more urbanized areas due to 

higher population density (Fig. TX-11; Tables TX-15 through 17). These index 

values can also be produced using high resolution cover data to determine local 

planting priority areas (e.g., neighborhoods). 

Urban Tree Benefi ts

The following forest attributes are estimated for the urban or community land 

in Texas (Table TX-1). These are rough estimates of values. More localized 

data are needed for more precise estimates, but these values reveal fi rst-order 

approximations. 

y 237.5 million trees

y 45.3 million metric tons of C stored ($1.0 billion value)

y 1.5 million metric tons/year of C sequestered ($34.1 million value)

y 46,090 metric tons/year total pollution removal ($374.4 million value)

▪ 1,382 metric tons/year of CO removed ($1.9 million value)

▪ 5,592 metric tons/year NO2

 removed ($55.4 million value)

▪ 21,605 metric tons/year of O3

 removed ($214.0 million value)

▪ 3,055 metric tons/year of SO2

 removed ($7.4 million value) 

▪ 14,457 metric tons/year of PM10 removed ($95.6 million value)

Figure TX-11.—Planting priority index for county 

subdivisions. The higher the index value, the greater 

priority for planting.
42 GTR-NRS-59 Texas

Summary

The data presented in this report provide a better understanding of Texas’ urban 

and community forests. This information can be used to advance urban and 

community forest policy and management that could improve environmental 

quality and human health throughout the State. 

These data establish a baseline to assess future change and can be used to 

understand:

• Extent of the urban and community forest resource

• Variations in the resource across the State

• Magnitude and value of the urban and community forest resource

• Urban growth in Texas

• Implications of policy decisions related to urban sprawl and urban and 

community forest management
GTR-NRS-59 43

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GTR-NRS-59 45

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increasing infl uence of urban environments on U.S. forest management.

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impact on the U.S. forest resource (2000-2050). Journal of Forestry. 

103(8): 383-389.

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Buchanan, S.C.; Chernick, P.L.; Caverhill, E.; Krupnick, A.; Fritsche, 

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(June 2007).

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applied to urban forestry. Syracuse, NY: State University of New York, 

College of Environmental Science and Forestry. 95 p. Ph.D. dissertation.

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for mapping large-area impervious surfaces: synergistic use of Landsat7 ETM+ and high spatial resolution imagery. Canadian Journal of Remote 

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Agriculture, Forest Service, Southern Research Station. 11 p.
46 GTR-NRS-59

APPENDIX

Urban Forest Data: States of the South Central West Region

The following tables are generated to support state reports on urban and community forests of the 

South Central West states of Arkansas, Louisiana, Oklahoma, and Texas. For specifi c state data 

tables use the CD accompanying this publication and search within the regional or state folder, or 

go to: http://www.nrs.fs.fed.us/data/urban.

State Specifi c Tables:

Table 1.—Statewide summary of population, area, population density, tree canopy and 

impervious surface land cover, and urban tree benefi ts in urban, community, and urban or 

community areas.

Table 2.—2000 population characteristics, population change (1990-2000), and percent of land 

classifi ed as urban within communities.

Table 3.—2000 population characteristics, population change (1990-2000), percent of land 

classifi ed as urban or as communities within county subdivisions.

Table 4.—2000 population characteristics, population change (1990-2000), percent of land 

classifi ed as urban or as communities within counties.

Table 5.—Tree canopy and impervious surface cover characteristics by community.

Table 6.—Tree canopy and impervious surface cover characteristics by county subdivision.

Table 7.—Tree canopy and impervious surface cover characteristics by county.

Table 8.—Land area, tree canopy cover, and available green space distributed within generalized 

land cover categories for communities.

Table 9.—Land area, tree canopy cover, and available green space distributed within generalized 

land cover categories for county subdivisions.

Table 10.—Land area, tree canopy cover, and available green space distributed within 

generalized land cover categories for counties.

Table 11.—Statistical summary of mapping zone values used to calculate urban and community 

forestry assessment.

Table 12.—Urban and community forestry assessment by community.

Table 13.—Urban and community forestry assessment by county subdivisions.

Table 14.—Urban and community forestry assessment by counties.

Table 15.—Planting priority index for communities.

Table 16.—Planting priority index for county subdivisions.

Table 17.—Planting priority index for counties.
Nowak, David J.; Greenfi eld, Eric J. 2010. Urban and community forests of the South Central West 

region: Arkansas, Louisiana, Oklahoma, Texas. Gen. Tech. Rep. NRS-59. Newtown Square, PA: 

U.S. Department of Agriculture, Forest Service, Northern Research Station. 46 p. [Includes CD-ROM].

This report details how land cover and urbanization vary within the states of Arkansas, Louisiana, 

Oklahoma, and Texas by community (incorporated and census designated places), county subdivision, 

and county. Specifi cally this report provides critical urban and community forestry information for each 

state including human population characteristics and trends, changes in urban and community lands, 

tree canopy and impervious surface cover characteristics, distribution of land-cover classes, a relative 

comparison of urban and community forests among local government types, determination of priority 

areas for tree planting, and a summary of urban tree benefi ts. Report information can improve the 

understanding, management, and planning of urban and community forests. This data is reported 

for each state on the CD provided in the back of this book and may be accessed by state at: 

http://www.nrs.fs.fed.us/data/urban.

KEY WORDS: urban forestry, tree cover, impervious cover, classifi ed land cover, ecosystem services, 

urbanization

The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of 

race, color, national origin, age, disability, and, where applicable, sex, marital status, familial status, parental status, 

religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or part of an individual’s 

income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with 

disabilities who require alternate means for communication of program information (Braille, large print, audiotape, 

etc.) should contact USDA’s TARGET Center at (202) 720-2600 (voice and TDD). To fi le a complaint of discrimination, 

write to USDA, Director, Offi ce of Civil Rights, 1400 Independence Avenue S.W., Washington, DC 20250-9410, or call 

(800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer.
Capitalizing on the strengths of existing science 

capacity in the Northeast and Midwest to attain a more 

integrated, cohesive, landscape-scale research program

www.nrs.fs.fed.us