United States

Department of

Agriculture

Forest Service

Northern

Research Station

General Technical

Report NRS-50

Urban and Community Forests

of the Southern Atlantic Region

Delaware

District of Columbia

Florida

Georgia

Maryland

David J. Nowak

Eric J. Greenfi eld

North Carolina

South Carolina

Virginia

West Virginia
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

September 2009 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 research forester with the Forest Service’s Northern Research Station at Syracuse, NY.

Manuscript received for publication April 2009

Abstract

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

Florida, Georgia, Maryland, North Carolina, South Carolina, Virginia, and West Virginia; 

and the District of Columbia by community (incorporated and census designated places), 

county subdivision, and county. Specifically 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 benefits. 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

Delaware’s	Urban	and	Community	Forests	11

District	of	Columbia’s	Urban	and	Community	Forests	19

Florida’s	Urban	and	Community	Forests	25

Georgia’s	Urban	and	Community	Forests	33

Maryland’s	Urban	and	Community	Forests	41

North	Carolina’s	Urban	and	Community	Forests	49

South	Carolina’s	Urban	and	Community	Forests	57

Virginia’s	Urban	and	Community	Forests	65

West	Virginia’s	Urban	and	Community	Forests	73

Literature	Cited	81

Appendix	85
GTR-NRS-50	 

INTRODUCTION

As	part	of	the	Forest	and	Rangeland	Renewable	Resources	Planning	Act	of	974,	the	

first 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 first 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 files) 

(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-specific urban and community forestry data.

This report includes information for the following states: Delaware, Florida, Georgia, 

Maryland, North Carolina, South Carolina, Virginia, and West Virginia; and the 

District of Columbia.

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 defined legal or statistical divisions. “County”

	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 

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



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-50

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

• Classified land-cover characteristics

• Relative comparisons of urban and community 

forests	

• Priority areas for tree planting

• Urban tree benefits

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 field 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 findings 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 definitions overlap: “community” 

and “urban”. The definition of community is based 

on jurisdictional or political boundaries delimited by 

U.S. Census definitions 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 definition of urban is based on population density 

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

definition: 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-50	 3

More specifically, 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 definition tends to be more restrictive than the 

1990 U.S. Census urban definition and encompasses 

many areas typically considered suburban. The 2000 

Census definition 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 definition) and community 

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

communities that are recognized by their geopolitical 

boundaries (political definition), both definitions 

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 definitions. 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 benefits. 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 filled 

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 influences on urban 

air temperatures and water flows 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-50

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).

Classified Land-cover Characteristics

Land-cover types also are summarized using 2001 

Landsat satellite data that were classified with the U.S. 

Geological Survey land cover categorization scheme 

based on a modified Anderson land-cover classification 

(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 

defined 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 

classified land-cover characteristics for communities, 

county subdivisions, and counties and state 

respectively (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 classification accuracy and efficiency (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-50	 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
	 GTR-NRS-50

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 Benefits

Urban and community forests are important for human 

and ecological health (Nowak and Dwyer 2007). The 

benefits 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 

benefits 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-50	 7

To estimate pollution by urban trees in each state, state 

pollutant flux 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 flux 

rates were adjusted to 2000 values based on average 

regional	pollution	concentration	changes	between	

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

flux rate = deposition velocity *	pollution	

concentration,

the ratio of the pollution concentration between years 

was used to update the flux 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 flux 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-50

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 finer 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 simplified 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 

simplification 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 coefficients 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 (Greenfield et al. 

in press). These findings 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 significantly among 

geographic units. Despite the potential underestimates 

in tree canopy cover values, relative comparisons 

3

Nowak, D.J.; Greenfield, E.J. Tree and impervious cover 

in the conterminous United States: Testing of NLCD cover 

estimates by mapping zone. In review. 
GTR-NRS-50	 9

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 refined and locally 

appropriate data, local field 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 field 

data, data from several urban and community forests 

Margin		 Significant

Mapping zone a n b NLCD c

 PI d Difference e of error f difference g

 46 709 55.9% 71.1% 15.2% 3.4% Yes

 48 760 45.0% 62.8% 17.8% 3.5% Yes

 53 223 66.8% 77.1% 10.3% 5.6% Yes

 54 993 55.7% 69.1% 13.4% 2.9% Yes

 55 995 51.1% 66.5% 15.4% 3.0% Yes

 56 990 22.8% 40.5% 17.7% 3.1% Yes

 57 642 66.9% 80.7% 13.8% 3.1% Yes

 58 998 39.9% 58.1% 18.3% 3.1% Yes

 59 958 52.5% 67.2% 14.7% 3.0% Yes

 60 972 37.5% 51.5% 14.1% 3.2% Yes

 61 632 55.0% 69.0% 14.0% 3.7% Yes

 62 845 50.0% 58.3% 8.4% 3.4% Yes

a NLCD mapping zones.

b Number of photo-interpreted sample points

c

 Percent tree canopy value derived from NLCD data

d Percent tree canopy derived from photo-interpreted data

e PI value minus NLCD value

f

	95%	confidence	interval	of	PI	value

g	Significant	difference	between	NLCD	and	PI	values	if	NLCD	value	is	outside	of	95%	confidence	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

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 significant environmental benefits. 

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 flow 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 

benefits 
10 GTR-NRS-50

• 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 benefits of urban and community forests

• Promote more detailed and/or locally 

appropriate urban and community forest 

inventories, censuses, or field 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 

specific 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-50								Delaware	 

Statewide	Summary

Urban or community land in Delaware comprises about 17.8 percent of the state 

land area in 2000, an increase from 14.0 percent in 1990. Statewide tree canopy 

cover averages 23.1 percent and tree cover in urban or community areas is about 

16.4 percent, with 15.5 percent impervious surface cover and 19.4 percent of 

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

community land in Delaware has an estimated 7.1 million trees, which store 

about 1.3 million metric tons of carbon ($29.6 million), and annually remove 

about 44,000 metric tons of carbon ($1.0 million) and 1,710 metric tons of air 

pollution ($13.5 million) (Table DE-1).

Tables DE-2 through DE-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.

Delaware’s Urban 

anD CommUnity Forests
12 GTR-NRS-50								Delaware

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

land	is	based	on	jurisdictional	or	political	boundaries	of	communities	based	on	United	States	Census	definitions	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). 

Delaware Statewide Urban a Community b

 Urban or

Community c

Population

2000 783,600 627,758 344,549 n/a

1990 666,168 486,501 255,939 n/a

% Change (1990-2000) 17.6 29.0 34.6 n/a

% Total population (2000) 100.0 80.1 44.0 n/a

Total area 

km2 (2000) 6,447.2 786.5 464.9 925.4

km2 (1990) 6,447.2 599.9 339.3 728.4

% Change (1990-2000) 0.0 31.1 37.0 27.0

Land area 

km2 (2000) 5,059.5 780.2 445.3 902.5

% Land area (2000) 100.0 15.4 8.8 17.8

km2 (1990) 5,059.5 596.6 320.5 708.4

% Land area (1990) 100.0 11.8 6.3 14.0

% Change (1990-2000) 0.0 30.8 38.9 27.4

Population density 

 (people/land area km2)

2000 154.9 804.6 773.8 n/a

1990 131.7 815.4 798.5 n/a

% Change (1990-2000) 17.6 -1.3 -3.1 n/a

Tree canopy cover (2000)

km2 1,166.6 129.5 65.9 147.9

% Land area 23.1 16.6 14.8 16.4

Per capita (m2/person) 1,488.8 206.3 191.2 n/a

% Canopy green space d 23.9 19.9 17.9 19.4

Total green space (2000) e km2 4,884.0 651.0 368.6 762.6

% Land area 96.5 83.4 82.8 84.5

Available green space (2000) f km2 3,717.4 521.4 302.7 614.7

% Land area 73.5 66.8 68.0 68.1

Impervious surface cover 

 (2000)

km2 175.4 129.3 76.7 139.8

% Land area 3.5 16.6 17.2 15.5

Per capita (m2/person) 223.9 206.0 222.6 n/a

Urban	tree	benefits	(2000)

Estimated number of trees n/a 6,200,000 3,100,000 7,100,000

Carbon

Carbon stored (metric tons) n/a 1,200,000 600,000 1,300,000

Carbon stored ($) n/a $27,400,000 $13,700,000 $29,600,000

Carbon sequestered (metric tons/year) n/a 39,000 20,000 44,000

Carbon sequestered ($/year) n/a $889,000 $456,000 $1,003,000

Pollution

CO removed (metric tons/year) n/a 25 13 29

CO removed ($/year) n/a $35,200 $17,900 $40,200

NO2 removed (metric tons/year) n/a 212 108 242

NO2 removed ($/year) n/a $2,098,600 $1,067,200 $2,396,300

O3 removed (metric tons/year) n/a 651 331 744

O3 removed ($/year) n/a $6,453,000 $3,282,000 $7,368,000

SO2 removed (metric tons/year) n/a 194 99 221

SO2 removed ($/year) n/a $469,800 $238,900 $536,500

PM10 removed (metric tons/year) n/a 417 212 476

PM10 removed ($/year) n/a $2,756,700 $1,401,900 $3,147,800

Total pollution removal (metric tons/year) n/a 1,500 760 1,710

Total pollution removal ($/year) n/a $11,800,000 $6,000,000 $13,500,000

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

cover, and urban tree benefits in urban, community, and urban or community areas.
GTR-NRS-50								Delaware	 13

Figure DE-1.—Urban or community land 

in 2000; urban area relative to community 

boundaries.

Figure DE-2.—2000 population within 

county subdivision boundaries.

Human	Population	Characteristics	and	Trends	

The population in Delaware increased 17.6 percent, from 

666,168 in 1990 to 783,600 in 2000 (Table DE-1). In Delaware, 

80.1 percent of the State’s population is in urban areas 

(Fig. DE-1), and 44.0 percent of the population is within 

communities (Fig. DE-2).

Urban	and	Community	Land	

Urban land comprises 15.4 percent of the land area of Delaware, 

while lands within communities make up 8.8 percent of the State

(Fig. DE-1). Between 1990 and 2000, urban area increased 30.8 

percent, while community land increased from 6.3 to 8.8 percent

(Table DE-1). Urban area in Delaware is projected to increase to 

39.5 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. DE-3; Tables 

DE-2 through 4).

Figure DE-3.—Percent of county 

subdivision	area	classified	as	urban	land	

in 2000.
4 GTR-NRS-50								Delaware

Tree	Canopy	Cover	Characteristics

Tree canopy cover in Delaware averages 23.1 percent 

(Fig. DE-4), with 96.5 percent total green space, 23.9 

percent canopy green space, and 1,488.8 m2

 of canopy 

cover per capita. Average tree cover in urban areas in 

Delaware was 16.6 percent, with 83.4 percent total green 

space, 19.9 percent canopy green space, and 206.3 m2

of canopy cover per capita. Within community lands 

in Delaware, average tree cover was 14.8 percent, with 

82.8 percent total green space, 17.9 percent canopy green 

space, and 191.2 m2

 of canopy cover per capita (Table 

DE-1). Tree canopy cover, canopy green space, and tree 

cover per capita varied among communities, county 

subdivisions, and counties (Fig. DE-5 through 6; Tables 

DE-5 through 7).

Figure DE-4.—Percentage tree canopy 

cover.

Figure DE-6.—Percentage tree canopy 

green space in county subdivisions.

Figure DE-5.—Percentage tree canopy 

cover within county subdivisions.
GTR-NRS-50								Delaware	 15

Figure DE-7.—Percentage impervious 

surface cover.

Figure DE-8.—Percentage impervious 

surface cover within county subdivisions.

Impervious	Surface	Cover	Characteristics

Average impervious surface cover in Delaware is 3.5 percent of the land area 

(Fig. DE-7), with 223.9 m2

 of impervious surface cover per capita. Average 

impervious surface cover in urban areas was 16.6 percent, with 206.0 m2

	of	

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

average impervious surface cover was 17.2 percent with 222.6 m2

 of impervious 

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

State (Fig. DE-8; Tables DE-5 through 7).
16 GTR-NRS-50 Delaware

Figure DE-9.—Classified land cover. Figure DE-10.—Relative comparisons 

of tree cover for county subdivisions.

Classified Land-cover Characteristics

Delaware’s	land	cover	is	dominated	by	agricultural	land	(Fig.	DE-9).	The	

characteristics	as	a	percent	of	the	total	land	area	in	Delaware	are	(Tables	DE-8	

through	10):

•	Agricultural	–	57.5	percent

•	Forested	–	25.3	percent

•	Developed	–	10.2	percent

•	Wetland	–	5.7	percent

•	Barren	–	1.3	percent

Relative Comparisons of Tree Cover

Out	of	the	75	Delaware	communities,	none	received	a	rating	of	excellent	and		

66 received	a	rating	of	poor	(Table	DE-12).	Of	the	27	county	subdivisions,	none	

had	a	rating	of	excellent	and	11	were	rated	poor	(Fig.	DE-10,	Table	DE-13);	and	

out	of	three	counties,	none	were	given	a	rating	of	excellent	and	two	were	given	a	

rating	of	poor	(Table	DE-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.	DE-10;	Tables	DE-11	

through	14).	
GTR-NRS-50								Delaware	 7

Figure DE-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. DE-11; Tables DE-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 Benefits

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

in Delaware (Table DE-1). These are rough estimates of values. More localized 

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

approximations. 

 7.1 million trees

 1.3 million metric tons of C stored ($29.6 million value)

 44,000 metric tons/year of C sequestered ($1.0 million value)

 1,710 metric tons/year total pollution removal ($13.5 million value)

▪ 29 metric tons/year of CO removed ($40,200 value)

▪ 242 metric tons/year NO2

 removed ($2.4 million value)

▪ 744 metric tons/year of O3

 removed ($7.4 million value)

▪ 221 metric tons/year of SO2

 removed ($536,000 value) 

▪ 476 metric tons/year of PM10 removed ($3.1 million value)
18 GTR-NRS-50								Delaware

Summary

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

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

community forest management
GTR-NRS-50								District	of	Columbia	 9

District-wide Summary

In the District of Columbia, tree canopy cover averages 16.0 percent, with 

41.1 percent impervious surface cover and 27.2 percent of the total green space 

covered by tree canopy cover. In the District of Columbia, a field assessment of 

the urban forest was conducted in 2004 (Nowak et al. 2006c). The District of 

Columbia has an estimated 1.9 million trees, which store about 474,000 metric 

tons of carbon ($10.8 million), and annually remove about 14,600 metric tons 

of carbon ($334,000) and 490 metric tons of air pollution ($3.7 million) 

(Table DC-1).

Tables DC-2, 5, 8, and 11 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.

DistriCt oF ColUmbia’s 

Urban anD CommUnity Forests
20 GTR-NRS-50								District	of	Columbia

Table DC-1.—District-wide summary of population, area, population density, tree canopy and impervious surface land 

cover, and urban tree benefits in urban and community areas.

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

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

 Canopy green space is the tree canopy cover divided by total green space. d Total green space (TGS) is total area – impervious surface cover – water. e Available green space (AGS) is total green space – tree canopy cover (if the calculated value is less than 0, then value set at 0). f

 Based on data from Nowak 

et al. (2006c), and not from methods detailed in this report. Dollar values are updated to 2007 values. 

District of Columbia District-wide Urban a Community b

Population

2000 572,059 572,059 572,059

1990 606,900 606,900 606,900

% Change (1990-2000) -5.7 -5.7 -5.7

% Total population (2000) 100.0 100.0 100.0

Total area 

km2 (2000) 177.0 158.9 177.0

km2 (1990) 177.0 159.2 177.0

% Change (1990-2000) 0.0 -0.1 0.0

Land area 

km2 (2000) 160.1 157.7 160.1

% Land area (2000) 100.0 98.5 100.0

km2 (1990) 160.1 158.0 160.1

% Land area (1990) 100.0 98.6 100.0

% Change (1990-2000) 0.0 -0.2 0.0

Population density 

(people/land area km2)

2000 3,572.7 3,627.1 3,572.7

1990 3,790.3 3,842.2 3,791.2

% Change (1990-2000) -5.7 -5.6 -5.8

Tree canopy cover (2000)

km2 25.7 25.2 25.7

% Land area 16.0 16.0 16.0

Per capita (m2/person) 44.9 44.1 44.9

% Canopy green space c 27.2 27.3 27.2

Total green space (2000) d km2 94.4 92.3 94.4

% Land area 58.9 58.5 58.9

Available green space (2000) e km2 68.7 67.1 68.7

% Land area 42.9 42.5 42.9

Impervious surface cover (2000)

km2 65.8 65.4 65.8

% Land area 41.1 41.5 41.1

Per capita (m2/person) 114.9 114.3 114.9

Urban	tree	benefits	(2000)	f

Estimated number of trees 1,928,000 n/a n/a

Carbon

Carbon stored (metric tons) 474,000 n/a n/a

Carbon stored ($) 10,800,000 n/a n/a

Carbon sequestered (metric tons/year) 14,600 n/a n/a

Carbon sequestered ($/year) 334,000 n/a n/a

Pollution

CO removed (metric tons/year) 23 n/a n/a

CO removed ($/year) 32,000 n/a n/a

NO2 removed (metric tons/year) 65 n/a n/a

NO2 removed ($/year) 645,000 n/a n/a

O3 removed (metric tons/year) 196 n/a n/a

O3 removed ($/year) 1,939,000 n/a n/a

SO2 removed (metric tons/year) 66 n/a n/a

SO2 removed ($/year) 160,000 n/a n/a

PM10 removed (metric tons/year) 140 n/a n/a

PM10 removed ($/year) 928,000 n/a n/a

Total pollution removal (metric tons/year) 490 n/a n/a

Total pollution removal ($/year) 3,700,000 n/a n/a
GTR-NRS-50								District	of	Columbia	 21

Human	Population	Characteristics		

and	Trends	

The population in the District of Columbia decreased 5.7 percent, from 606,900 

in 1990 to 572,059 in 2000 (Table DC-1). 

Urban	Land	

Urban land comprises 98.5 percent of the land area of the District of Columbia. 

Between 1990 and 2000, urban area decreased 0.2 percent. The percentages are 

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

from U.S. Census cartographic boundary data (Table DC-2).

Tree	Canopy	Cover	Characteristics

Tree canopy cover in the District of Columbia averages 16.0 percent (Fig. DC-4), 

with 58.9 percent total green space, 27.2 percent canopy green space, and 

44.9 m2

 of canopy cover per capita. Average tree cover in urban areas in District 

of Columbia was 16.0 percent, with 58.5 percent total green space, 27.3 percent 

canopy green space, and 44.1 m2

 of canopy cover per capita (Table DC-5).

Figure DC-4.—Percentage tree canopy cover.
22 GTR-NRS-50								District	of	Columbia

Figure DC-7.—Percentage impervious surface cover.

Impervious	Surface	Cover	Characteristics

Average impervious surface cover in the District of Columbia is 41.1 percent of 

the land area (Fig. DC-7), with 114.9 m2

 of impervious surface cover per capita. 

Average impervious surface cover in urban areas was 41.5 percent, with 114.3 m2

of impervious surface cover per capita. (Table DC-5).

Classified Land-cover Characteristics

The District of Columbia’s land cover is dominated by developed land 

(Fig. DC-9). The characteristics as a percent of the total land area in the District 

of Columbia are (Table DC-8):

• Developed – 83.5 percent

• Forested – 11.7 percent

• Agricultural – 3.7 percent

• Barren – 0.6 percent

• Wetland – 0.6 percent
GTR-NRS-50								District	of	Columbia	 23

Urban Tree Benefits

The following forest attributes are estimated for the District of Columbia 

(Nowak et al. 2006c) (Table DC-1). 

 1.9 million trees

 474,000 metric tons of C stored ($10.8 million value)

 14,600 metric tons/year of C sequestered ($334,000 value)

 490 metric tons/year total pollution removal ($3.7 million value)

▪ 23 metric tons/year of CO removed ($32,000 value)

▪ 65 metric tons/year NO2

 removed ($645,000 value)

▪ 196 metric tons/year of O3

 removed ($1.9 million value)

▪ 66 metric tons/year of SO2

 removed ($160,000 value) 

▪ 140 metric tons/year of PM10 removed ($928,000 value)

Figure	DC-9.—Classified	land	cover.
24 GTR-NRS-50								District	of	Columbia

Summary

The data presented in this report provide a better understanding of the District 

of Columbia’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 district. 

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 district

• Magnitude and value of the urban and community forest resource

• Urban growth in the District of Columbia

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

community forest management
GTR-NRS-50								Florida	 25

Statewide	Summary

Urban or community land in Florida comprises about 16.2 percent of the state 

land area in 2000, an increase from 12.5 percent in 1990. Statewide tree canopy 

cover averages 38.4 percent and tree cover in urban or community areas is about 

26.7 percent, with 16.9 percent impervious surface cover and 32.1 percent of the 

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

land in Florida has an estimated 292 million trees, which store about 55.7 million 

metric tons of carbon ($1.3 billion), and annually remove about 1.8 million 

metric tons of carbon ($41.9 million) and 65,750 metric tons of air pollution 

($540.5 million) (Table FL-1).

Tables FL-2 through FL-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.

FloriDa’s Urban 

anD CommUnity Forests
26 GTR-NRS-50								Florida

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

land	is	based	on	jurisdictional	or	political	boundaries	of	communities	based	on	United	States	Census	definitions	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). 

Florida Statewide Urban a Community b

 Urban or

Community c

Population

2000 15,982,378 14,270,020 12,006,286 n/a

1990 12,937,926 10,967,328 8,541,795 n/a

% Change (1990-2000) 23.5 30.1 40.6 n/a

% Total population (2000) 100.0 89.3 75.1 n/a

Total area 

km2 (2000) 170,303.6 16,350.3 19,328.2 24,555.1

km2 (1990) 170,303.6 13,070.4 15,160.5 19,141.9

% Change (1990-2000) 0.0 25.1 27.5 28.3

Land area 

km2 (2000) 141,705.9 15,901.6 17,853.7 22,933.9

% Land area (2000) 100.0 11.2 12.6 16.2

km2 (1990) 141,705.9 12,753.9 13,822.3 17,696.6

% Land area (1990) 100.0 9.0 9.8 12.5

% Change (1990-2000) 0.0 24.7 29.2 29.6

Population density 

 (people/land area km2)

2000 112.8 897.4 672.5 n/a

1990 91.3 859.9 618.0 n/a

% Change (1990-2000) 23.5 4.4 8.8 n/a

Tree canopy cover (2000)

km2 54,422.5 3,599.9 4,767.1 6,122.0

% Land area 38.4 22.6 26.7 26.7

Per capita (m2/person) 3,405.2 252.3 397.0 n/a

% Canopy green space d 39.7 29.0 32.4 32.1

Total green space (2000) e km2 136,964.0 12,413.9 14,733.6 19,058.0

% Land area 96.7 78.1 82.5 83.1

Available green space (2000) f km2 82,542.1 8,814.8 9,967.2 12,936.8

% Land area 58.2 55.4 55.8 56.4

Impervious surface cover 

 (2000)

km2 4,742.3 3,487.7 3,120.1 3,875.9

% Land area 3.3 21.9 17.5 16.9

Per capita (m2/person) 296.7 244.4 259.9 n/a

Urban	tree	benefits	(2000)

Estimated number of trees n/a 171,700,000 227,300,000 292,000,000

Carbon

Carbon stored (metric tons) n/a 32,800,000 43,400,000 55,700,000

Carbon stored ($) n/a $747,800,000 $989,500,000 $1,270,000,000

Carbon sequestered (metric tons/year) n/a 1,080,000 1,430,000 1,837,000

Carbon sequestered ($/year) n/a $24,624,000 $32,604,000 $41,884,000

Pollution

CO removed (metric tons/year) n/a 1,030 1,364 1,751

CO removed ($/year) n/a $1,448,900 $1,918,600 $2,464,000

NO2 removed (metric tons/year) n/a 4,084 5,408 6,945

NO2 removed ($/year) n/a $40,454,000 $53,570,500 $68,797,100

O3 removed (metric tons/year) n/a 20,121 26,644 34,218

O3 removed ($/year) n/a $199,316,000 $263,940,000 $338,961,000

SO2 removed (metric tons/year) n/a 2,919 3,865 4,964

SO2 removed ($/year) n/a $7,078,600 $9,373,700 $12,038,000

PM10 removed (metric tons/year) n/a 10,510 13,918 17,874

PM10 removed ($/year) n/a $69,516,400 $92,055,900 $118,221,300

Total pollution removal (metric tons/year) n/a 38,660 51,200 65,750

Total pollution removal ($/year) n/a $317,800,000 $420,900,000 $540,500,000

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

cover, and urban tree benefits in urban, community, and urban or community areas.
GTR-NRS-50								Florida	 27

Figure FL-1.—Urban or community land in 2000; urban area 

relative to community boundaries.

Figure FL-3.—Percent of county subdivision area 

classified	as	urban	land	in	2000.

Human	Population	Characteristics		

and	Trends	

The population in Florida increased 23.5 percent, 

from 12,937,926 in 1990 to 15,982,378 in 2000 (Table 

FL-1). In Florida, 89.3 percent of the State’s population 

is in urban areas (Fig. FL-1), and 75.1 percent of the 

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

Urban	and	Community	Land	

Urban land comprises 11.2 percent of the land area 

of Florida, while lands within communities make up 

12.6 percent of the State (Fig. FL-1). Between 1990 

and 2000, urban area increased 24.7 percent, while 

community land increased from 9.8 to 12.6 percent 

(Table FL-1). Urban area in Florida is projected to 

increase to 27.9 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. FL-3; 

Tables FL-2 through 4).

Figure FL-2.—2000 population within county subdivision 

boundaries.
28 GTR-NRS-50								Florida

Figure FL-4.—Percentage tree canopy cover. Figure FL-5.—Percentage tree canopy cover within county 

subdivisions.

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

county subdivisions.

Tree	Canopy	Cover	Characteristics

Tree canopy cover in Florida averages 38.4 percent 

(Fig. FL-4), with 96.7 percent total green space, 

39.7 percent canopy green space, and 3,405.2 m2

	of	

canopy cover per capita. Average tree cover in urban 

areas in Florida was 22.6 percent, with 78.1 percent 

total green space, 29.0 percent canopy green space, 

and 252.3 m2

 of canopy cover per capita. Within 

community lands in Florida, average tree cover was 

26.7 percent, with 82.5 percent total green space, 

32.4 percent canopy green space, and 397.0 m2

	of	

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

cover, canopy green space, and tree cover per capita 

varied among communities, county subdivisions,

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

through 7).
GTR-NRS-50								Florida	 29

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

within county subdivisions.

Impervious	Surface	Cover	Characteristics

Average impervious surface cover in Florida is 3.3 percent of the land area 

(Fig. FL-7), with 296.7 m2

 of impervious surface cover per capita. Average 

impervious surface cover in urban areas was 21.9 percent, with 244.4 m2

	of	

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

impervious surface cover was 17.5 percent with 259.9 m2

 of impervious surface 

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

(Fig. FL-8; Tables FL-5 through 7).
30 GTR-NRS-50 Florida

Figure FL-9.—Classified land cover. Figure FL-10.—Relative comparisons of tree cover for 

county subdivisions.

Classified Land-cover Characteristics

Florida’s	land	cover	is	dominated	by	agricultural	land	(Fig.	FL-9).	The	

characteristics	as	a	percent	of	the	total	land	area	in	Florida	are	(Tables	FL-8	

through	10):

•	Agricultural	–	44.2	percent

•	Forested	–	21.4	percent

•	Developed	–	14.3	percent

•	Wetland	–	10.3	percent

•	Grassland	–	5.6	percent

•	Scrub/Shrub	–	3.8	percent

•	Barren	–	0.5	percent

Relative Comparisons of Tree Cover

Out	of	the	888	Florida	communities,	18	received	a	rating	of	excellent	and	446	

received	a	rating	of	poor	(Table	FL-12).	Of	the	299	county	subdivisions,	22	had	a	

rating	of	excellent	and	70	were	rated	poor	(Fig.	FL-10,	Table	FL-13);	and	out	of	

67 counties,	eight	were	given	a	rating	of	excellent	and	15	were	given	a	rating	of	

poor	(Table	FL-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.	FL-10;	Tables	FL-11	through	

14).	
GTR-NRS-50 Florida 31

Figure FL-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.	FL-11;	Tables	FL-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 Benefits

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

in	Florida	(Table	FL-1).	These	are	rough	estimates	of	values.	More	localized	

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

approximations.	

	292	million	trees

	55.7	million	metric	tons	of	C	stored	($1.3	billion	value)

	1.8	million	metric	tons/year	of	C	sequestered	($41.9	million	value)

	65,750	metric	tons/year	total	pollution	removal	($540.5	million	value)

▪ 1,751 metric tons/year of CO removed ($2.5 million value)

▪ 6,945 metric tons/year NO2

	removed	($68.8	million	value)

▪ 34,218 metric tons/year of O3

	removed	($339.0	million	value)

▪ 4,964 metric tons/year of SO2

	removed	($12.0	million	value)	

▪ 17,874 metric tons/year of PM10	removed	($118.2	million	value).
32 GTR-NRS-50 Florida

Summary

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

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

community	forest	management
GTR-NRS-50 Georgia 33

Statewide Summary

Urban	or	community	land	in	Georgia	comprises	about	9.6	percent	of	the	state	

land area in 2000, an increase from 7.3 percent in 1990. Statewide tree canopy 

cover	averages	52.0	percent	and	tree	cover	in	urban	or	community	areas	is		

about	42.6	percent,	with	11.8	percent	impervious	surface	cover	and	48.3	percent	

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

community	land	in	Georgia	has	an	estimated	293.1	million	trees,	which	store	

about	55.9	million	metric	tons	of	carbon	($1.3	billion),	and	annually	remove	

about	1.8	million	metric	tons	of	carbon	($42.0	million)	and	49,670	metric	tons		

of	air	pollution	($410.4	million)	(Table	GA-1).

Tables	GA-2	through	GA-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.

GeorGia’s Urban 

and CommUnity Forests
34 GTR-NRS-50 Georgia

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

land is based on jurisdictional or political boundaries of communities based on United States Census definitions 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). 

Georgia Statewide Urban a Community b

 Urban or

Community c

Population

2000 8,186,453 5,864,163 3,809,842 n/a

1990 6,478,216 4,097,339 2,836,318 n/a

% Change (1990-2000) 26.4 43.1 34.3 n/a

% Total population (2000) 100.0 71.6 46.5 n/a

Total area 

km2 (2000) 153,909.4 9,718.5 9,724.0 14,694.8

km2 (1990) 153,909.4 7,304.9 8,009.1 11,220.5

% Change (1990-2000) 0.0 33.0 21.4 31.0

Land area 

km2 (2000) 150,135.0 9,622.0 9,530.8 14,438.7

% Land area (2000) 100.0 6.4 6.3 9.6

km2 (1990) 150,135.0 7,248.3 7,838.8 11,017.6

% Land area (1990) 100.0 4.8 5.2 7.3

% Change (1990-2000) 0.0 32.7 21.6 31.1

Population density 

 (people/land area km2)

2000 54.5 609.5 399.7 n/a

1990 43.1 565.3 361.8 n/a

% Change (1990-2000) 26.4 7.8 10.5 n/a

Tree canopy cover (2000)

km2 78,134.1 4,009.9 3,953.3 6,145.8

% Land area 52.0 41.7 41.5 42.6

Per capita (m2/person) 9,544.3 683.8 1,037.7 n/a

% Canopy green space d 53.0 49.1 47.2 48.3

Total green space (2000) e km2 147,430.0 8,165.5 8,372.1 12,735.4

% Land area 98.2 84.9 87.8 88.2

Available green space (2000) f km2 69,296.8 4,155.9 4,419.1 6,590.1

% Land area 46.2 43.2 46.4 45.6

Impervious surface cover 

 (2000)

km2 2,704.8 1,456.6 1,158.7 1,703.4

% Land area 1.8 15.1 12.2 11.8

Per capita (m2/person) 330.4 248.4 304.1 n/a

Urban tree benefits (2000)

Estimated number of trees n/a 191,200,000 188,500,000 293,100,000

Carbon

Carbon stored (metric tons) n/a 36,500,000 36,000,000 55,900,000

Carbon stored ($) n/a $832,200,000 $820,800,000 $1,274,500,000

Carbon sequestered (metric tons/year) n/a 1,203,000 1,186,000 1,844,000

Carbon sequestered ($/year) n/a $27,428,000 $27,041,000 $42,043,000

Pollution

CO removed (metric tons/year) n/a 866 854 1,328

CO removed ($/year) n/a $1,218,800 $1,201,600 $1,868,000

NO2 removed (metric tons/year) n/a 3,309 3,263 5,072

NO2 removed ($/year) n/a $32,783,400 $32,320,400 $50,244,700

O3 removed (metric tons/year) n/a 16,757 16,520 25,682

O3 removed ($/year) n/a $165,993,000 $163,649,000 $254,405,000

SO2 removed (metric tons/year) n/a 1,942 1,914 2,976

SO2 removed ($/year) n/a $4,708,400 $4,641,900 $7,216,200

PM10 removed (metric tons/year) n/a 9,532 9,397 14,609

PM10 removed ($/year) n/a $63,043,600 $62,153,300 $96,622,200

Total pollution removal (metric tons/year) n/a 32,410 31,950 49,670

Total pollution removal ($/year) n/a $267,700,000 $264,000,000 $410,400,000

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

cover, and urban tree benefits in urban, community, and urban or community areas.
GTR-NRS-50 Georgia 35

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

urban area relative to community boundaries.

Figure GA-2.—2000 population within county 

subdivision boundaries.

Figure GA-3.—Percent of county subdivision area 

classified as urban land in 2000.

Human Population Characteristics 

and Trends 

The	population	in	Georgia	increased	26.4	percent,	from	

6,478,216 in	1990	to	8,186,453	in	2000	(Table	GA-1).		

In Georgia, 71.6 percent of the State’s population is 

in	urban	areas	(Fig.	GA-1),	and	46.5	percent	of	the	

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

Urban and Community Land 

Urban	land	comprises	6.4	percent	of	the	land	area	of	

Georgia,	while	lands	within	communities	make	up	

6.3 percent of the State (Fig. GA-1). Between 1990 

and	2000,	urban	area	increased	32.7	percent,	while	

community	land	increased	from	5.2	to	6.3	percent		

(Table	GA-1).	Urban	area	in	Georgia	is	projected	to	

increase	to	14.3	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. GA-3; 

Tables	GA-2	through	4).
36 GTR-NRS-50 Georgia

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

county subdivisions.

Figure GA-6.—Percentage tree canopy green space 

in county subdivisions.

Tree Canopy Cover Characteristics

Tree	canopy	cover	in	Georgia	averages	52.0	percent	

(Fig.	GA-4),	with	98.2	percent	total	green	space,	

53.0	percent	canopy	green	space,	and	9,544.3	m2

	of	

canopy	cover	per	capita.	Average	tree	cover	in	urban	

areas	in	Georgia	was	41.7	percent,	with	84.9	percent	

total	green	space,	49.1	percent	canopy	green	space,	

and	683.8	m2

 of canopy cover per capita. Within 

community	lands	in	Georgia,	average	tree	cover	was	

41.5	percent,	with	87.8	percent	total	green	space,	

47.2	percent	canopy	green	space,	and	1,037.7	m2

	of	

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

cover,	canopy	green	space,	and	tree	cover	per	capita	

varied	among	communities,	county	subdivisions,		

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

through	7).
GTR-NRS-50 Georgia 37

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

within county subdivisions.

Impervious Surface Cover Characteristics

Average	impervious	surface	cover	in	Georgia	is	1.8	percent	of	the	land	area	

(Fig.	GA-7),	with	330.4	m2

	of	impervious	surface	cover	per	capita.	Average	

impervious	surface	cover	in	urban	areas	was	15.1	percent,	with	248.4	m2

	of	

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

impervious	surface	cover	was	12.2	percent	with	304.1	m2

	of	impervious	surface	

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

(Fig.	GA-8;	Tables	GA-5	through	7).
38 GTR-NRS-50 Georgia

Figure GA-9.—Classified land cover. Figure GA-10.—Relative comparisons of tree cover for 

county subdivisions.

Classified Land-cover Characteristics

Georgia’s	land	cover	is	dominated	by	forest	land	(Fig.	GA-9).	The	characteristics	

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

•	Forested	–	48.5	percent

•	Agricultural	–	30.7	percent

•	Developed	–	9.0	percent

•	Grassland	–	8.3	percent	

• Wetland – 1.7 percent

• Scrub/Shrub – 1.3 percent

• Barren – 0.5 percent

Relative Comparisons of Tree Cover

Out of the 596 Georgia communities, 16 received a rating of excellent and 114 

received a rating of poor (Table GA-12). Of the 577 county subdivisions, 23 

had	a	rating	of	excellent	and	98	were	rated	poor	(Fig.	GA-10,	Table	GA-13);	

and	out	of	159	counties,	13	were	given	a	rating	of	excellent	and	30	were	given	a	

rating	of	poor	(Table	GA-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.	GA-10;	Tables	GA-11	

through	14).		
GTR-NRS-50 Georgia 39

Figure GA-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.	GA-11;	Tables	GA-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 Benefits

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

in	Georgia	(Table	GA-1).	These	are	rough	estimates	of	values.	More	localized	

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

approximations.	

	293.1	million	trees

	55.9	million	metric	tons	of	C	stored	($1.3	billion	value)

	1.8	million	metric	tons/year	of	C	sequestered	($42.0	million	value)

	49,670	metric	tons/year	total	pollution	removal	($410.4	million	value)

▪ 1,328 metric tons/year of CO removed ($1.9 million value)

▪ 5,072 metric tons/year NO2

	removed	($50.2	million	value)

▪ 25,682 metric tons/year of O3

	removed	($254.4	million	value)

▪ 2,976 metric tons/year of SO2

	removed	($7.2	million	value)	

▪ 14,609 metric tons/year of PM10	removed	($96.6	million	value)
40 GTR-NRS-50 Georgia

Summary

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

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

community	forest	management
GTR-NRS-50 Maryland 41

Statewide Summary

Urban	or	community	land	in	Maryland	comprises	about	23.4	percent	of	the		

state land area in 2000, an increase from 20.1 percent in 1990. Statewide 

tree	canopy	cover	averages	35.0	percent	and	tree	cover	in	urban	or	community	

areas	is	about	29.2	percent,	with	13.2	percent	impervious	surface	cover	and		

33.7 percent of the total green space covered by tree canopy cover. Statewide, 

urban	or	community	land	in	Maryland	has	an	estimated	82.6	million	trees,	which	

store	about	15.8	million	metric	tons	of	carbon	($360.2	million),	and	annually	

remove	about	520,000	metric	tons	of	carbon	($11.9	million)	and	16,200	metric	

tons	of	air	pollution	($133.4	million)	(Table	MD-1).

Tables	MD-2	through	MD-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.

maryland’s Urban 

and CommUnity Forests
42 GTR-NRS-50 Maryland

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

land is based on jurisdictional or political boundaries of communities based on United States Census definitions 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). 

Maryland Statewide Urban a Community b

 Urban or

Community c

Population

2000 5,296,486 4,558,668 4,245,617 n/a

1990 4,781,468 3,888,429 3,777,020 n/a

% Change (1990-2000) 10.8 17.2 12.4 n/a

% Total population (2000) 100.0 86.1 80.2 n/a

Total area 

km2 (2000) 32,133.2 4,773.7 4,998.5 6,216.3

km2 (1990) 32,133.2 4,072.2 4,288.7 5,281.7

% Change (1990-2000) 0.0 17.2 16.6 17.7

Land area 

km2 (2000) 25,303.4 4,680.5 4,742.5 5,923.9

% Land area (2000) 100.0 18.5 18.7 23.4

km2 (1990) 25,303.4 4,046.1 4,110.5 5,096.0

% Land area (1990) 100.0 16.0 16.2 20.1

% Change (1990-2000) 0.0 15.7 15.4 16.2

Population density 

 (people/land area km2)

2000 209.3 974.0 895.2 n/a

1990 189.0 961.0 918.9 n/a

% Change (1990-2000) 10.8 1.3 -2.6 n/a

Tree canopy cover (2000)

km2 8,851.6 1,311.6 1,357.0 1,731.9

% Land area 35.0 28.0 28.6 29.2

Per capita (m2/person) 1,671.2 287.7 319.6 n/a

% Canopy green space d 36.3 33.2 33.5 33.7

Total green space (2000) e km2 24,382.4 3,948.8 4,051.3 5,140.8

% Land area 96.4 84.4 85.4 86.8

Available green space (2000) f km2 15,530.8 2,637.2 2,694.3 3,409.0

% Land area 61.4 56.3 56.8 57.5

Impervious surface cover 

 (2000)

km2 921.1 731.7 691.2 783.0

% Land area 3.6 15.6 14.6 13.2

Per capita (m2/person) 173.9 160.5 162.8 n/a

Urban tree benefits (2000)

Estimated number of trees n/a 62,600,000 64,700,000 82,600,000

Carbon

Carbon stored (metric tons) n/a 11,900,000 12,300,000 15,800,000

Carbon stored ($) n/a $271,300,000 $280,400,000 $360,200,000

Carbon sequestered (metric tons/year) n/a 393,000 407,000 520,000

Carbon sequestered ($/year) n/a $8,960,000 $9,280,000 $11,856,000

Pollution

CO removed (metric tons/year) n/a 199 206 263

CO removed ($/year) n/a $280,600 $290,300 $370,500

NO2 removed (metric tons/year) n/a 2,414 2,497 3,187

NO2 removed ($/year) n/a $23,910,300 $24,738,100 $31,571,200

O3 removed (metric tons/year) n/a 5,654 5,849 7,465

O3 removed ($/year) n/a $56,006,000 $57,945,000 $73,950,000

SO2 removed (metric tons/year) n/a 1,348 1,395 1,780

SO2 removed ($/year) n/a $3,269,500 $3,382,700 $4,317,100

PM10 removed (metric tons/year) n/a 2,655 2,746 3,505

PM10 removed ($/year) n/a $17,557,100 $18,165,000 $23,182,500

Total pollution removal (metric tons/year) n/a 12,270 12,690 16,200

Total pollution removal ($/year) n/a $101,000,000 $104,500,000 $133,400,000

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

cover, and urban tree benefits in urban, community, and urban or community areas.
GTR-NRS-50 Maryland 43

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

urban area relative to community boundaries.

Figure MD-2.—2000 population within county 

subdivision boundaries.

Figure MD-3.—Percent of county subdivision area 

classified as urban land in 2000.

Human Population Characteristics 

and Trends 

The	population	in	Maryland	increased	10.8	percent,	from	

4,781,468 in	1990	to	5,296,486	in	2000	(Table	MD-1).		

In Maryland, 86.1 percent of the State’s population is 

in	urban	areas	(Fig.	MD-1),	and	80.2	percent	of	the	

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

Urban and Community Land 

Urban	land	comprises	18.5	percent	of	the	land	area	of	

Maryland,	while	lands	within	communities	make	up	

18.7 percent of the State (Fig. MD-1). Between 1990 

and	2000,	urban	area	increased	15.7	percent,	while	

community	land	increased	from	16.2	to	18.7	percent	

(Table	MD-1).	Urban	area	in	Maryland	is	projected	to	

increase	to	37.5	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. MD-3; 

Tables	MD-2	through	4).
44 GTR-NRS-50 Maryland

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

county subdivisions.

Figure MD-6.—Percentage tree canopy green space 

in county subdivisions.

Tree Canopy Cover Characteristics

Tree	canopy	cover	in	Maryland	averages	35.0	percent	

(Fig.	MD-4),	with	96.4	percent	total	green	space,	

36.3	percent	canopy	green	space,	and	1,671.2	m2

	of	

canopy	cover	per	capita.	Average	tree	cover	in	urban	

areas	in	Maryland	was	28.0	percent,	with	84.4	percent	

total	green	space,	33.2	percent	canopy	green	space,	

and	287.7	m2

 of canopy cover per capita. Within 

community	lands	in	Maryland,	average	tree	cover	

was	28.6	percent,	with	85.4	percent	total	green	space,	

33.5	percent	canopy	green	space,	and	319.6	m2

	of	

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

cover,	canopy	green	space,	and	tree	cover	per	capita	

varied	among	communities,	county	subdivisions,		

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

through	7).
GTR-NRS-50 Maryland 45

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

within county subdivisions.

Impervious Surface Cover Characteristics

Average	impervious	surface	cover	in	Maryland	is	3.6	percent	of	the	land	area	

(Fig.	MD-7),	with	173.9	m2

	of	impervious	surface	cover	per	capita.	Average	

impervious	surface	cover	in	urban	areas	was	15.6	percent,	with	160.5	m2

	of	

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

average	impervious	surface	cover	was	14.6	percent	with	162.8	m2

	of	impervious	

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

the State (Fig. MD-8; Tables MD-5 through 7).
46 GTR-NRS-50 Maryland

Figure MD-9.—Classified land cover.

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

county subdivisions.

Classified Land-cover Characteristics

Maryland’s	land	cover	is	dominated	by	agricultural	land	(Fig.	MD-9).	The	

characteristics	as	a	percent	of	the	total	land	area	in	Maryland	are	(Tables	MD-8	

through	10):

•	Agricultural	–	44.3	percent

•	Forested	–	38.8	percent

•	Developed	–	12.2	percent

•	Wetland	–	3.5	percent

•	Barren	–	1.2	percent

Relative Comparisons of Tree Cover

Out	of	the	368	Maryland	communities,	eight	received	a	rating	of	excellent	and		

164	received	a	rating	of	poor	(Table	MD-12).	Of	the	293	county	subdivisions,	

two	had	a	rating	of	excellent	and	91	were	rated	poor	(Fig.	MD-10,	Table	MD-13);	

and	out	of	24	counties,	one	was	given	a	rating	of	excellent	and	ten	were	given	a	

rating	of	poor	(Table	MD-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.	MD-10;	Tables	MD-11	

through	14).	
GTR-NRS-50 Maryland 47

Figure MD-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.	MD-11;	Tables	MD-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 Benefits

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

in	Maryland	(Table	MD-1).	These	are	rough	estimates	of	values.	More	localized	

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

approximations.	

	82.6	million	trees

	15.8	million	metric	tons	of	C	stored	($360.2	million	value)

	520,000	metric	tons/year	of	C	sequestered	($11.9	million	value)

	16,200	metric	tons/year	total	pollution	removal	($133.4	million	value)

▪ 263 metric tons/year of CO removed ($370,500 value)

▪ 3,187 metric tons/year NO2

	removed	($31.6	million	value)

▪ 7,465 metric tons/year of O3

	removed	($74.0	million	value)

▪ 1,780 metric tons/year of SO2

	removed	($4.3	million	value)	

▪ 3,505 metric tons/year of PM10	removed	($23.2	million	value)
48 GTR-NRS-50 Maryland

Summary

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

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

community	forest	management
GTR-NRS-50 North Carolina 49

Statewide Summary

Urban or community land in North Carolina comprises about 10.3 percent of the 

state land area in 2000, an increase from 7.7 percent in 1990. Statewide 

tree	canopy	cover	averages	48.6	percent	and	tree	cover	in	urban	or	community	

areas	is	about	32.8	percent,	with	11.9	percent	impervious	surface	cover	and		

37.2 percent of the total green space covered by tree canopy cover. Statewide, 

urban or community land in North Carolina has an estimated 202.6 million 

trees,	which	store	about	38.7	million	metric	tons	of	carbon	($882.4	million),	and	

annually	remove	about	1.3	million	metric	tons	of	carbon	($29.0	million)	and	

36,590 metric tons of air pollution ($293 million) (Table NC-1).

Tables NC-2 through NC-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.

north Carolina’s Urban 

and CommUnity Forests
50 GTR-NRS-50 North Carolina

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

land is based on jurisdictional or political boundaries of communities based on United States Census definitions 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). 

North Carolina Statewide Urban a Community b

 Urban or

Community c

Population

2000 8,049,313 4,849,482 4,349,946 n/a

1990 6,628,637 3,337,778 3,273,560 n/a

% Change (1990-2000) 21.4 45.3 32.9 n/a

% Total population (2000) 100.0 60.2 54.0 n/a

Total area 

km2 (2000) 139,389.3 9,250.2 9,848.1 13,247.6

km2 (1990) 139,389.3 7,134.9 7,145.1 9,864.2

% Change (1990-2000) 0.0 29.6 37.8 34.3

Land area 

km2 (2000) 126,122.9 9,176.5 9,605.5 12,967.8

% Land area (2000) 100.0 7.3 7.6 10.3

km2 (1990) 126,122.9 7,101.0 6,970.7 9,674.2

% Land area (1990) 100.0 5.6 5.5 7.7

% Change (1990-2000) 0.0 29.2 37.8 34.0

Population density 

 (people/land area km2)

2000 63.8 528.5 452.9 n/a

1990 52.6 470.0 469.6 n/a

% Change (1990-2000) 21.4 12.4 -3.6 n/a

Tree canopy cover (2000)

km2 61,317.0 2,870.4 2,991.2 4,248.2

% Land area 48.6 31.3 31.1 32.8

Per capita (m2/person) 7,617.7 591.9 687.7 n/a

% Canopy green space d 49.5 36.4 36.2 37.2

Total green space (2000) e km2 123,814.0 7,875.0 8,263.5 11,421.5

% Land area 98.2 85.8 86.0 88.1

Available green space (2000) f km2 62,497.6 5,004.7 5,272.4 7,173.5

% Land area 49.6 54.5 54.9 55.3

Impervious surface cover 

 (2000)

km2 2,308.7 1,301.5 1,342.0 1,546.3

% Land area 1.8 14.2 14.0 11.9

Per capita (m2/person) 286.8 268.4 308.5 n/a

Urban tree benefits (2000)

Estimated number of trees n/a 136,900,000 142,700,000 202,600,000

Carbon

Carbon stored (metric tons) n/a 26,100,000 27,200,000 38,700,000

Carbon stored ($) n/a $595,100,000 $620,200,000 $882,400,000

Carbon sequestered (metric tons/year) n/a 861,000 897,000 1,274,000

Carbon sequestered ($/year) n/a $19,631,000 $20,452,000 $29,047,000

Pollution

CO removed (metric tons/year) n/a 595 620 881

CO removed ($/year) n/a $837,200 $872,400 $1,239,400

NO2 removed (metric tons/year) n/a 2,578 2,687 3,816

NO2 removed ($/year) n/a $25,539,500 $26,614,900 $37,798,600

O3 removed (metric tons/year) n/a 12,305 12,823 18,211

O3 removed ($/year) n/a $121,892,000 $127,024,000 $180,400,000

SO2 removed (metric tons/year) n/a 2,739 2,855 4,054

SO2 removed ($/year) n/a $6,642,600 $6,922,300 $9,831,200

PM10 removed (metric tons/year) n/a 6,507 6,781 9,631

PM10 removed ($/year) n/a $43,039,200 $44,851,400 $63,698,200

Total pollution removal (metric tons/year) n/a 24,720 25,770 36,590

Total pollution removal ($/year) n/a $198,000,000 $206,300,000 $293,000,000

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

cover, and urban tree benefits in urban, community, and urban or community areas.
GTR-NRS-50 North Carolina 51

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

urban area relative to community boundaries.

Figure NC-2.—2000 population within county 

subdivision boundaries.

Figure NC-3.—Percent of county subdivision area 

classified as urban land in 2000.

Human Population Characteristics 

and Trends 

The population in North Carolina increased 21.4 percent, 

from	6,628,637	in	1990	to	8,049,313	in	2000	(Table	

NC-1). In North Carolina, 60.2 percent of the State’s 

population is in urban areas (Fig. NC-1), and 54.0 

percent	of	the	population	is	within	communities		

(Fig. NC-2).

Urban and Community Land 

Urban	land	comprises	7.3	percent	of	the	land	area	of	

North Carolina, while lands within communities make 

up 7.6 percent of the State (Fig. NC-1). Between 1990 

and	2000,	urban	area	increased	29.2	percent,	while	

community	land	increased	from	5.5	to	7.6	percent	(Table	

NC-1). Urban area in North Carolina is projected to 

increase	to	19.1	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. NC-3; 

Tables NC-2 through 4).
52 GTR-NRS-50 North Carolina

Figure NC-4.—Percentage tree canopy cover.

Figure NC-5.—Percentage tree canopy cover within 

county subdivisions.

Figure NC-6.—Percentage tree canopy green space 

in county subdivisions.

Tree Canopy Cover Characteristics

Tree canopy cover in North Carolina averages 

48.6 percent (Fig. NC-4), with 98.2 percent total 

green	space,	49.5	percent	canopy	green	space,	and	

7,617.7 m2

	of	canopy	cover	per	capita.	Average		

tree cover in urban areas in North Carolina was 

31.3	percent,	with	85.8	percent	total	green	space,	

36.4	percent	canopy	green	space,	and	591.9	m2

	of	

canopy cover per capita. Within community lands in 

North Carolina, average tree cover was 31.1 percent, 

with	86.0	percent	total	green	space,	36.2	percent	

canopy	green	space,	and	687.7	m2

	of	canopy	cover	

per capita (Table NC-1). Tree canopy cover, canopy 

green	space,	and	tree	cover	per	capita	varied	among	

communities,	county	subdivisions,	and	counties		

(Fig. NC-5 through 6; Tables NC-5 through 7).
GTR-NRS-50 North Carolina 53

Figure NC-7.—Percentage impervious surface cover.

Figure NC-8.—Percentage impervious surface cover 

within county subdivisions.

Impervious Surface Cover Characteristics

Average impervious surface cover in North Carolina is 1.8 percent of the land 

area (Fig. NC-7), with 286.8 m2

	of	impervious	surface	cover	per	capita.	Average	

impervious	surface	cover	in	urban	areas	was	14.2	percent,	with	268.4	m2

	of	

impervious surface cover per capita. Within community lands in North Carolina, 

average	impervious	surface	cover	was	14.0	percent	with	308.5	m2

	of	impervious	

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

the State (Fig. NC-8; Tables NC-5 through 7).
54 GTR-NRS-50 North Carolina

Figure NC-9.—Classified land cover.

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

county subdivisions.

Classified Land-cover Characteristics

North Carolina’s land cover is dominated by forest land (Fig. NC-9). The 

characteristics as a percent of the total land area in North Carolina are 

(Tables NC-8 through 10):

•	Forested	–	46.0	percent

•	Agricultural	–	34.5	percent

•	Developed	–	9.6	percent

•	Grassland	–	6.0	percent

• Scrub/Shrub – 2.3 percent

• Wetland – 1.2 percent

• Barren – 0.4 percent

Relative Comparisons of Tree Cover

Out of the 655 North Carolina communities, 22 received a rating of excellent and 

152 received a rating of poor (Table NC-12). Of the 1,055 county subdivisions, 

51 had a rating of excellent and 145 were rated poor (Fig. NC-10, Table NC-13); 

and	out	of	100	counties,	12	were	given	a	rating	of	excellent	and	32	were	given	a	

rating of poor (Table NC-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. NC-10; Tables NC-11 

through	14).	
GTR-NRS-50 North Carolina 55

Figure NC-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. NC-11; Tables NC-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 Benefits

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

in North Carolina (Table NC-1). These are rough estimates of values. More 

localized	data	are	needed	for	more	precise	estimates,	but	these	values	reveal		

first-order approximations. 

	202.6	million	trees

	38.7	million	metric	tons	of	C	stored	($882.4	million	value)

	1.3	million	metric	tons/year	of	C	sequestered	($29.0	million	value)

	36,590	metric	tons/year	total	pollution	removal	($293	million	value)

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

▪ 3,816 metric tons/year NO2

	removed	($37.8	million	value)

▪ 18,211 metric tons/year of O3

	removed	($180.4	million	value)

▪ 4,054 metric tons/year of SO2

	removed	($9.8	million	value)	

▪ 9,631 metric tons/year of PM10	removed	($63.7	million	value)
56 GTR-NRS-50 North Carolina

Summary

The data presented in this report provide a better understanding of North 

Carolina’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 North Carolina

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

community	forest	management
GTR-NRS-50 South Carolina 57

Statewide Summary

Urban or community land in South Carolina comprises about 9.2 percent 

of the state land area in 2000, an increase from 7.3 percent in 1990. Statewide 

tree	canopy	cover	averages	46.8	percent	and	tree	cover	in	urban	or	community	

areas	is	about	35.4	percent,	with	10.9	percent	impervious	surface	cover	and		

39.7 percent of the total green space covered by tree canopy cover. Statewide, 

urban or community land in South Carolina has an estimated 121.5 million trees, 

which	store	about	23.2	million	metric	tons	of	carbon	($529	million),	and	annually	

remove	about	765,000	metric	tons	of	carbon	($17.4	million)	and	23,420	metric	

tons of air pollution ($179.8 million) (Table SC-1).

Tables SC-2 through SC-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.

soUth Carolina’s Urban 

and CommUnity Forests
58 GTR-NRS-50 South Carolina

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

land is based on jurisdictional or political boundaries of communities based on United States Census definitions 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). 

South Carolina Statewide Urban a Community b

 Urban or

Community c

Population

2000 4,012,012 2,427,124 1,836,965 n/a

1990 3,486,703 1,905,378 1,572,089 n/a

% Change (1990-2000) 15.1 27.4 16.8 n/a

% Total population (2000) 100.0 60.5 45.8 n/a

Total area 

km2 (2000) 82,931.9 4,842.0 5,332.2 7,479.5

km2 (1990) 82,931.9 3,934.9 4,177.3 5,902.3

% Change (1990-2000) 0.0 23.1 27.6 26.7

Land area 

km2 (2000) 77,937.2 4,786.1 5,083.0 7,207.0

% Land area (2000) 100.0 6.1 6.5 9.2

km2 (1990) 77,937.2 3,900.3 4,010.2 5,719.5

% Land area (1990) 100.0 5.0 5.1 7.3

% Change (1990-2000) 0.0 22.7 26.8 26.0

Population density 

 (people/land area km2)

2000 51.5 507.1 361.4 n/a

1990 44.7 488.5 392.0 n/a

% Change (1990-2000) 15.1 3.8 -7.8 n/a

Tree canopy cover (2000)

km2 36,469.6 1,610.9 1,778.1 2,548.5

% Land area 46.8 33.7 35.0 35.4

Per capita (m2/person) 9,090.1 663.7 967.9 n/a

% Canopy green space d 47.6 39.3 39.4 39.7

Total green space (2000) e km2 76,636.4 4,103.0 4,511.4 6,423.5

% Land area 98.3 85.7 88.8 89.1

Available green space (2000) f km2 40,167.1 2,492.2 2,733.4 3,875.1

% Land area 51.5 52.1 53.8 53.8

Impervious surface cover 

 (2000)

km2 1,300.8 683.1 571.6 783.5

% Land area 1.7 14.3 11.2 10.9

Per capita (m2/person) 324.2 281.5 311.2 n/a

Urban tree benefits (2000)

Estimated number of trees n/a 76,800,000 84,800,000 121,500,000

Carbon

Carbon stored (metric tons) n/a 14,700,000 16,200,000 23,200,000

Carbon stored ($) n/a $335,200,000 $369,400,000 $529,000,000

Carbon sequestered (metric tons/year) n/a 483,000 533,000 765,000

Carbon sequestered ($/year) n/a $11,012,000 $12,152,000 $17,442,000

Pollution

CO removed (metric tons/year) n/a 361 398 571

CO removed ($/year) n/a $507,600 $560,300 $803,000

NO2 removed (metric tons/year) n/a 1,222 1,349 1,933

NO2 removed ($/year) n/a $12,104,000 $13,360,100 $19,149,000

O3 removed (metric tons/year) n/a 6,822 7,530 10,793

O3 removed ($/year) n/a $67,579,000 $74,592,000 $106,912,000

SO2 removed (metric tons/year) n/a 2,116 2,336 3,348

SO2 removed ($/year) n/a $5,131,600 $5,664,100 $8,118,400

PM10 removed (metric tons/year) n/a 4,281 4,726 6,773

PM10 removed ($/year) n/a $28,317,300 $31,255,900 $44,799,100

Total pollution removal (metric tons/year) n/a 14,800 16,340 23,420

Total pollution removal ($/year) n/a $113,600,000 $125,400,000 $179,800,000

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

cover, and urban tree benefits in urban, community, and urban or community areas.
GTR-NRS-50 South Carolina 59

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

urban area relative to community boundaries.

Figure SC-2.—2000 population within county 

subdivision boundaries.

Figure SC-3.—Percent of county subdivision area 

classified as urban land in 2000.

Human Population Characteristics 

and Trends 

The population in South Carolina increased 15.1 percent, 

from	3,486,703	in	1990	to	4,012,012	in	2000	(Table	

SC-1). In South Carolina, 60.5 percent of the State’s 

population is in urban areas (Fig. SC-1), and 45.8 percent 

of the population is within communities (Fig. SC-2).

Urban and Community Land 

Urban	land	comprises	6.1	percent	of	the	land	area	of	

South Carolina, while lands within communities make 

up 6.5 percent of the State (Fig. SC-1). Between 1990 

and	2000,	urban	area	increased	22.7	percent,	while	

community	land	increased	from	5.1	to	6.5	percent		

(Table SC-1). Urban area in South Carolina is projected 

to	increase	to	18.3	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. SC-3; Tables SC-2 through 4).
60 GTR-NRS-50 South Carolina

Figure SC-4.—Percentage tree canopy cover.

Figure SC-5.—Percentage tree canopy cover within 

county subdivisions.

Figure SC-6.—Percentage tree canopy green space 

in county subdivisions.

Tree Canopy Cover Characteristics

Tree canopy cover in South Carolina averages 

46.8 percent (Fig. SC-4), with 98.3 percent total 

green	space,	47.6	percent	canopy	green	space,	and	

9,090.1 m2

	of	canopy	cover	per	capita.	Average		

tree cover in urban areas in South Carolina was 

33.7	percent,	with	85.7	percent	total	green	space,		

39.3	percent	canopy	green	space,	and	663.7	m2

	of	

canopy cover per capita. Within community lands in 

South Carolina, average tree cover was 35.0 percent, 

with	88.8	percent	total	green	space,	39.4	percent	

canopy	green	space,	and	967.9	m2

	of	canopy	cover	

per capita (Table SC-1). Tree canopy cover, canopy 

green	space,	and	tree	cover	per	capita	varied	among	

communities,	county	subdivisions,	and	counties		

(Fig. SC-5 through 6; Tables SC-5 through 7).
GTR-NRS-50 South Carolina 61

Figure SC-7.—Percentage impervious surface cover.

Figure SC-8.—Percentage impervious surface cover 

within county subdivisions.

Impervious Surface Cover Characteristics

Average	impervious	surface	cover	in	South	Carolina	is	1.7	percent	of	the	land	

area	(Fig.	SC-7),	with	324.2	m2

	of	impervious	surface	cover	per	capita.	Average	

impervious	surface	cover	in	urban	areas	was	14.3	percent,	with	281.5	m2

	of	

impervious	surface	cover	per	capita.	Within	community	lands	in	South	Carolina,	

average	impervious	surface	cover	was	11.2	percent	with	311.2	m2

	of	impervious	

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

State (Fig.	SC-8;	Tables	SC-5	through	7).
62 GTR-NRS-50 South Carolina

Figure SC-9.—Classified land cover.

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

county subdivisions.

Classified Land-cover Characteristics

South	Carolina’s	land	cover	is	dominated	by	forest	land	(Fig.	SC-9).		

The	characteristics	as	a	percent	of	the	total	land	area	in	South	Carolina	are		

(Tables	SC-8	through	10):

•	Forested	–	42.5	percent

•	Agricultural	–	34.1	percent

•	Grassland	–	9.7	percent	

•	Developed	–	8.5	percent

•	Wetland	–	2.5	percent

•	Scrub/Shrub	–	2.2	percent

•	Barren	–	0.5	percent

Relative Comparisons of Tree Cover

Out	of	the	368	South	Carolina	communities,	13 received	a	rating	of	excellent	and	

61 received	a	rating	of	poor	(Table	SC-12).	Of	the	296	county	subdivisions,	12	

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

out	of	46	counties,	seven	were	given	a	rating	of	excellent	and	seven	were	given	a	

rating	of	poor	(Table	SC-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.	SC-10;	Tables	SC-11	

through	14).	
GTR-NRS-50 South Carolina 63

Figure SC-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.	SC-11;	Tables	SC-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 Benefits

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

in	South	Carolina	(Table	SC-1).	These	are	rough	estimates	of	values.	More	

localized	data	are	needed	for	more	precise	estimates,	but	these	values	reveal		

first-order approximations. 

	121.5	million	trees

	23.2	million	metric	tons	of	C	stored	($529	million	value)

	765,000	metric	tons/year	of	C	sequestered	($17.4	million	value)

	23,420	metric	tons/year	total	pollution	removal	($179.8	million	value)

▪ 571 metric tons/year of CO removed ($803,000 value)

▪ 1,933 metric tons/year NO2

	removed	($19.1	million	value)

▪ 10,793 metric tons/year of O3

	removed	($106.9	million	value)

▪ 3,348 metric tons/year of SO2

	removed	($8.1	million	value)	

▪ 6,773 metric tons/year of PM10	removed	($44.8	million	value)
64 GTR-NRS-50 South Carolina

Summary

The	data	presented	in	this	report	provide	a	better	understanding	of	South	

Carolina’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	South	Carolina

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

community	forest	management
GTR-NRS-50 Virginia 65

Statewide Summary

Urban	or	community	land	in	Virginia	comprises	about	9.8	percent	of	the	state	

land	area	in	2000,	an	increase	from	8.4	percent	in	1990.	Statewide	tree	canopy	

cover	averages	54.4	percent	and	tree	cover	in	urban	or	community	areas	is	about	

34.5	percent,	with	11.5	percent	impervious	surface	cover	and	39.0	percent	of	the	

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

land	in	Virginia	has	an	estimated	165.8	million	trees,	which	store	about	31.6	

million	metric	tons	of	carbon	($720.5	million),	and	annually	remove	about	

1.0	million	metric	tons	of	carbon	($23.8	million)	and	27,310	metric	tons	of	air	

pollution	($227	million)	(Table	VA-1).

Tables	VA-2	through	VA-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.

Virginia’s Urban 

and CommUnity Forests
66 GTR-NRS-50 Virginia

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

land is based on jurisdictional or political boundaries of communities based on United States Census definitions 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). 

Virginia Statewide Urban a Community b

 Urban or

Community c

Population

2000 7,078,515 5,169,955 4,367,421 n/a

1990 6,187,358 4,293,443 3,951,499 n/a

% Change (1990-2000) 14.4 20.4 10.5 n/a

% Total population (2000) 100.0 73.0 61.7 n/a

Total area 

km2 (2000) 110,784.7 6,329.0 8,513.0 10,555.3

km2 (1990) 110,784.7 5,212.3 7,686.3 9,078.0

% Change (1990-2000) 0.0 21.4 10.8 16.3

Land area 

km2 (2000) 102,554.6 6,198.3 8,063.6 10,080.9

% Land area (2000) 100.0 6.0 7.9 9.8

km2 (1990) 102,554.6 5,168.9 7,276.8 8,659.5

% Land area (1990) 100.0 5.0 7.1 8.4

% Change (1990-2000) 0.0 19.9 10.8 16.4

Population density 

 (people/land area km2)

2000 69.0 834.1 541.6 n/a

1990 60.3 830.6 543.0 n/a

% Change (1990-2000) 14.4 0.4 -0.3 n/a

Tree canopy cover (2000)

km2 55,815.8 1,788.5 2,735.0 3,476.4

% Land area 54.4 28.9 33.9 34.5

Per capita (m2/person) 7,885.2 345.9 626.2 n/a

% Canopy green space d 55.4 34.7 38.5 39.0

Total green space (2000) e km2 100,814.0 5,156.7 7,108.2 8,917.1

% Land area 98.3 83.2 88.2 88.5

Available green space (2000) f km2 45,006.7 3,369.2 4,374.5 5,442.1

% Land area 43.9 54.4 54.3 54.0

Impervious surface cover 

 (2000)

km2 1,740.4 1,041.5 955.4 1,163.9

% Land area 1.7 16.8 11.8 11.5

Per capita (m2/person) 245.9 201.5 218.8 n/a

Urban tree benefits (2000)

Estimated number of trees n/a 85,300,000 130,400,000 165,800,000

Carbon

Carbon stored (metric tons) n/a 16,300,000 24,900,000 31,600,000

Carbon stored ($) n/a $371,600,000 $567,700,000 $720,500,000

Carbon sequestered (metric tons/year) n/a 537,000 820,000 1,043,000

Carbon sequestered ($/year) n/a $12,244,000 $18,696,000 $23,780,000

Pollution

CO removed (metric tons/year) n/a 216 330 419

CO removed ($/year) n/a $303,600 $464,300 $590,200

NO2 removed (metric tons/year) n/a 1,749 2,674 3,399

NO2 removed ($/year) n/a $17,323,300 $26,490,500 $33,671,200

O3 removed (metric tons/year) n/a 7,561 11,563 14,697

O3 removed ($/year) n/a $74,903,000 $114,540,000 $145,589,000

SO2 removed (metric tons/year) n/a 1,354 2,070 2,631

SO2 removed ($/year) n/a $3,282,600 $5,019,700 $6,380,400

PM10 removed (metric tons/year) n/a 3,169 4,846 6,159

PM10 removed ($/year) n/a $20,959,500 $32,050,900 $40,738,900

Total pollution removal (metric tons/year) n/a 14,050 21,480 27,310

Total pollution removal ($/year) n/a $116,800,000 $178,600,000 $227,000,000

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

cover, and urban tree benefits in urban, community, and urban or community areas.
GTR-NRS-50 Virginia 67

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

urban area relative to community boundaries.

Figure VA-2.—2000 population within county 

subdivision boundaries.

Figure VA-3.—Percent of county subdivision area 

classified as urban land in 2000.

Human Population Characteristics 

and Trends 

The	population	in	Virginia	increased	14.4	percent,		

from	6,187,358	in	1990	to	7,078,515	in	2000	(Table	

VA-1).	In	Virginia,	73.0	percent	of	the	State’s	population	

is	in	urban	areas	(Fig.	VA-1),	and	61.7	percent	of	the	

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

Urban and Community Land 

Urban	land	comprises	6.0	percent	of	the	land	area		

of	Virginia,	while	lands	within	communities	make	up		

7.9	percent	of	the	State	(Fig.	VA-1).	Between	1990	

and	2000,	urban	area	increased	19.9	percent,	while	

community	land	increased	from	7.1	to	7.9	percent	(Table	

VA-1).	Urban	area	in	Virginia	is	projected	to	increase	to	

12.6	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.	VA-3;	

Tables	VA-2	through	4).
68 GTR-NRS-50 Virginia

Figure VA-4.—Percentage tree canopy cover.

Figure VA-5.—Percentage tree canopy cover within 

county subdivisions.

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

county subdivisions.

Tree Canopy Cover Characteristics

Tree	canopy	cover	in	Virginia	averages	54.4	percent	

(Fig.	VA-4),	with	98.3	percent	total	green	space,	

55.4	percent	canopy	green	space,	and	7,885.2	m2

	of	

canopy	cover	per	capita.	Average	tree	cover	in	urban	

areas	in	Virginia	was	28.9	percent,	with	83.2	percent	

total	green	space,	34.7	percent	canopy	green	space,	

and	345.9	m2

	of	canopy	cover	per	capita.	Within	

community	lands	in	Virginia,	average	tree	cover	was	

33.9	percent,	with	88.2	percent	total	green	space,	

38.5	percent	canopy	green	space,	and	626.2	m2

	of	

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

cover,	canopy	green	space,	and	tree	cover	per	capita	

varied	among	communities,	county	subdivisions,	and	

counties	(Fig.	VA-5	through	6;	Tables	VA-5		

through	7).
GTR-NRS-50 Virginia 69

Figure VA-7.—Percentage impervious surface cover.

Figure VA-8.—Percentage impervious surface cover 

within county subdivisions.

Impervious Surface Cover Characteristics

Average	impervious	surface	cover	in	Virginia	is	1.7	percent	of	the	land	area		

(Fig.	VA-7),	with	245.9	m2

	of	impervious	surface	cover	per	capita.	Average	

impervious	surface	cover	in	urban	areas	was	16.8	percent,	with	201.5	m2

	of	

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

average	impervious	surface	cover	was	11.8	percent	with	218.8	m2

	of	impervious	

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

State (Fig.	VA-8;	Tables	VA-5	through	7).
70 GTR-NRS-50 Virginia

Figure VA-9.—Classified land cover.

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

county subdivisions.

Classified Land-cover Characteristics

Virginia’s	land	cover	is	dominated	by	forest	land	(Fig.	VA-9).	The	characteristics	

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

•	Forested	–	61.5	percent

•	Agricultural	–	26.9	percent

•	Developed	–	7.7	percent

•	Grassland	–	1.5	percent

•	Wetland	–	1.0	percent

•	Barren	–	0.8	percent

•	Scrub/Shrub	–	0.7	percent

Relative Comparisons of Tree Cover

Out	of	the	371	Virginia	communities,	nine	received	a	rating	of	excellent	and	

140	received	a	rating	of	poor	(Table	VA-12).	Of	the	544	county	subdivisions,	

24 had	a	rating	of	excellent	and	57	were	rated	poor	(Fig.	VA-10,	Table	VA-13);	

and	out	of	135	counties,	26	were	given	a	rating	of	excellent	and	28	were	given	a	

rating	of	poor	(Table	VA-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.	VA-10;	Tables	VA-11	

through	14).	
GTR-NRS-50 Virginia 71

Figure VA-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.	VA-11;	Tables	VA-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 Benefits

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

in	Virginia	(Table	VA-1).	These	are	rough	estimates	of	values.	More	localized	

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

approximations.	

	165.8	million	trees

	31.6	million	metric	tons	of	C	stored	($720.5	million	value)

	1.0	million	metric	tons/year	of	C	sequestered	($23.8	million	value)

	27,310	metric	tons/year	total	pollution	removal	($227	million	value)

▪ 419 metric tons/year of CO removed ($590,200 value)

▪ 3,399 metric tons/year NO2

	removed	($33.7	million	value)

▪ 14,697 metric tons/year of O3

	removed	($145.6	million	value)

▪ 2,631 metric tons/year of SO2

	removed	($6.4	million	value)	

▪ 6,159 metric tons/year of PM10	removed	($40.7	million	value)
72 GTR-NRS-50 Virginia

Summary

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

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

community	forest	management
GTR-NRS-50 West Virginia 73

Statewide Summary

Urban	or	community	land	in	West	Virginia	comprises	about	4.1	percent	of		

the	state	land	area	in	2000,	an	increase	from	3.8	percent	in	1990.	Statewide		

tree	canopy	cover	averages	69.3	percent	and	tree	cover	in	urban	or	community	

areas	is	about	47.2	percent,	with	12.4	percent	impervious	surface	cover	and		

53.9	percent	of	the	total	green	space	covered	by	tree	canopy	cover.	Statewide,	

urban	or	community	land	in	West	Virginia	has	an	estimated	57.6	million	trees,	

which	store	about	11	million	metric	tons	of	carbon	($250.8	million),	and	annually	

remove	about	363,000	metric	tons	of	carbon	($8.3	million)	and	7,240	metric	tons	

of	air	pollution	($57.2	million)	(Table	WV-1).

Tables	WV-2	through	WV-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.

West Virginia’s Urban 

and CommUnity Forests
74 GTR-NRS-50 West Virginia

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

land is based on jurisdictional or political boundaries of communities based on United States Census definitions 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). 

West Virginia Statewide Urban a Community b

 Urban or

Community c

Population

2000 1,808,344 832,780 760,120 n/a

1990 1,793,477 648,184 769,498 n/a

% Change (1990-2000) 0.8 28.5 -1.2 n/a

% Total population (2000) 100.0 46.1 42.0 n/a

Total area 

km2 (2000) 62,754.8 1,463.7 2,013.3 2,633.0

km2 (1990) 62,754.8 1,318.9 1,844.5 2,405.8

% Change (1990-2000) 0.0 11.0 9.2 9.4

Land area 

km2 (2000) 62,203.7 1,440.3 1,949.2 2,559.0

% Land area (2000) 100.0 2.3 3.1 4.1

km2 (1990) 62,203.7 1,301.3 1,783.7 2,336.5

% Land area (1990) 100.0 2.1 2.9 3.8

% Change (1990-2000) 0.0 10.7 9.3 9.5

Population density 

 (people/land area km2)

2000 29.1 578.2 390.0 n/a

1990 28.8 498.1 431.4 n/a

% Change (1990-2000) 0.8 16.1 -9.6 n/a

Tree canopy cover (2000)

km2 43,086.6 502.5 967.7 1,208.6

% Land area 69.3 34.9 49.6 47.2

Per capita (m2/person) 23,826.5 603.4 1,273.0 n/a

% Canopy green space d 70.1 42.6 57.0 53.9

Total green space (2000) e km2 61,506.0 1,181.0 1,697.5 2,241.7

% Land area 98.9 82.0 87.1 87.6

Available green space (2000) f km2 18,428.1 679.4 731.5 1,035.0

% Land area 29.6 47.2 37.5 40.4

Impervious surface cover 

 (2000)

km2 697.7 259.3 251.7 317.3

% Land area 1.1 18.0 12.9 12.4

Per capita (m2/person) 385.8 311.4 331.1 n/a

Urban tree benefits (2000)

Estimated number of trees n/a 24,000,000 46,100,000 57,600,000

Carbon

Carbon stored (metric tons) n/a 4,600,000 8,800,000 11,000,000

Carbon stored ($) n/a $104,900,000 $200,600,000 $250,800,000

Carbon sequestered (metric tons/year) n/a 151,000 290,000 363,000

Carbon sequestered ($/year) n/a $3,443,000 $6,612,000 $8,276,000

Pollution

CO removed (metric tons/year) n/a 31 59 74

CO removed ($/year) n/a $43,300 $83,400 $104,100

NO2 removed (metric tons/year) n/a 360 693 865

NO2 removed ($/year) n/a $3,563,100 $6,861,200 $8,569,700

O3 removed (metric tons/year) n/a 1,389 2,675 3,341

O3 removed ($/year) n/a $13,760,000 $26,498,000 $33,096,000

SO2 removed (metric tons/year) n/a 406 782 977

SO2 removed ($/year) n/a $985,300 $1,897,400 $2,369,900

PM10 removed (metric tons/year) n/a 824 1,586 1,981

PM10 removed ($/year) n/a $5,448,100 $10,491,100 $13,103,600

Total pollution removal (metric tons/year) n/a 3,010 5,800 7,240

Total pollution removal ($/year) n/a $23,800,000 $45,800,000 $57,200,000

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

cover, and urban tree benefits in urban, community, and urban or community areas.
GTR-NRS-50 West Virginia 75

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

urban area relative to community boundaries.

Figure WV-2.—2000 population within county 

subdivision boundaries.

Figure WV-3.—Percent of county subdivision area 

classified as urban land in 2000.

Human Population Characteristics 

and Trends 

The	population	in	West	Virginia	increased	0.8	percent,	

from	1,793,477	in	1990	to	1,808,344	in	2000	(Table	

WV-1).	In	West	Virginia,	46.1	percent	of	the	State’s	

population	is	in	urban	areas	(Fig.	WV-1),	and	42.0	

percent	of	the	population	is	within	communities		

(Fig.	WV-2).

Urban and Community Land 

Urban	land	comprises	2.3	percent	of	the	land	area	of	

West	Virginia,	while	lands	within	communities	make	

up 3.1	percent	of	the	State	(Fig.	WV-1).	Between	1990	

and	2000,	urban	area	increased	10.7	percent,	while	

community	land	increased	from	2.9	to	3.1	percent	(Table	

WV-1).	Urban	area	in	West	Virginia	is	projected	to	

increase	to	7.7	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.	WV-3;	

Tables	WV-2	through	4).
76 GTR-NRS-50 West Virginia

Figure WV-4.—Percentage tree canopy cover.

Figure WV-5.—Percentage tree canopy cover within 

county subdivisions.

Figure WV-6.—Percentage tree canopy green space 

in county subdivisions.

Tree Canopy Cover Characteristics

Tree	canopy	cover	in	West	Virginia	averages		

69.3	percent	(Fig.	WV-4),	with	98.9	percent	total	

green	space,	70.1	percent	canopy	green	space,	and	

23,826.5	m2

	of	canopy	cover	per	capita.	Average		

tree	cover	in	urban	areas	in	West	Virginia	was		

34.9	percent,	with	82.0	percent	total	green	space,		

42.6	percent	canopy	green	space,	and	603.4	m2

	of	

canopy	cover	per	capita.	Within	community	lands	in	

West	Virginia,	average	tree	cover	was	49.6	percent,	

with	87.1	percent	total	green	space,	57.0	percent	

canopy	green	space,	and	1,273.0	m2

	of	canopy	cover	

per	capita	(Table	WV-1).	Tree	canopy	cover,	canopy	

green	space,	and	tree	cover	per	capita	varied	among	

communities,	county	subdivisions,	and	counties		

(Fig.	WV-5	through	6;	Tables	WV-5	through	7).
GTR-NRS-50 West Virginia 77

Figure WV-7.—Percentage impervious surface cover.

Figure WV-8.—Percentage impervious surface cover 

within county subdivisions.

Impervious Surface Cover Characteristics

Average	impervious	surface	cover	in	West	Virginia	is	1.1	percent	of	the	land	

area	(Fig.	WV-7),	with	385.8	m2

	of	impervious	surface	cover	per	capita.	Average	

impervious	surface	cover	in	urban	areas	was	18.0	percent,	with	311.4	m2

	of	

impervious	surface	cover	per	capita.	Within	community	lands	in	West	Virginia,	

average	impervious	surface	cover	was	12.9	percent	with	331.1	m2

	of	impervious	

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

the	State	(Fig.	WV-8;	Tables	WV-5	through	7).
78 GTR-NRS-50 West Virginia

Figure WV-9.—Classified land cover.

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

county subdivisions.

Classified Land-cover Characteristics

West	Virginia’s	land	cover	is	dominated	by	forest	land	(Fig.	WV-9).		

The	characteristics	as	a	percent	of	the	total	land	area	in	West	Virginia	are		

(Tables	WV-8	through	10):

•	Forested	–	81.6	percent

•	Agricultural	–	9.5	percent

•	Developed	–	6.9	percent

•	Grassland	–	1.4	percent	

•	Barren	–	0.6	percent

•	Wetland	–	0.1	percent

•	Scrub/Shrub	–	less	than	0.1	percent

Relative Comparisons of Tree Cover

Out	of	the	282	West	Virginia	communities,	28	received	a	rating	of	excellent	and	

64 received	a	rating	of	poor	(Table	WV-12).	Of	the	240	county	subdivisions,	35	

had	a	rating	of	excellent	and	nine	were	rated	poor	(Fig.	WV-10,	Table	WV-13);	

and	out	of	55	counties,	14	were	given	a	rating	of	excellent	and	one	was	given	a	

rating	of	poor	(Table	WV-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.	WV-10;	Tables	WV-11	

through	14).	
GTR-NRS-50 West Virginia 79

Figure WV-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.	WV-11;	Tables	WV-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 Benefits

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

West	Virginia	(Table	WV-1).	These	are	rough	estimates	of	values.	More	localized	

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

approximations.	

	57.6	million	trees

	11	million	metric	tons	of	C	stored	($250.8	million	value)

	363,000	metric	tons/year	of	C	sequestered	($8.3	million	value)

	7,240	metric	tons/year	total	pollution	removal	($57.2	million	value)

▪ 74 metric tons/year of CO removed ($104,100 value)

▪ 865 metric tons/year NO2

	removed	($8.6	million	value)

▪ 3,341 metric tons/year of O3

	removed	($33.1	million	value)

▪ 977 metric tons/year of SO2

	removed	($2.4	million	value)	

▪ 1,981 metric tons/year of PM10	removed	($13.1	million	value)
80 GTR-NRS-50 West Virginia

Summary

The	data	presented	in	this	report	provide	a	better	understanding	of	West	

Virginia’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	West	Virginia

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

community	forest	management
GTR-NRS-50 81

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increasing influence of urban environments on U.S. forest management.

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GTR-NRS-50	 85

Appendix

Urban Forest data: States of the Southern Atlantic Region

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

the	Southern	Atlantic	States	of	Delaware,	Florida,	Georgia,	Maryland,	North	Carolina,	South	

Carolina, Virginia, and West Virginia, and the District of Columbia. For specific 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 Specific Tables:

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

impervious surface land cover, and urban tree benefits in urban, community, and urban or 

community	areas.

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

classified as urban within communities.

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

classified as urban or as communities within county subdivisions.

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

classified 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.; Greenfield, Eric J. 2009. Urban and community forests of the Southern Atlantic 

region: Delaware, District of Columbia, Florida, Georgia, Maryland, North Carolina, South Carolina, 

Virginia, West Virginia. Gen. Tech. Rep. NRS-50. Newtown Square, PA: U.S. Department of Agriculture, 

Forest Service, Northern Research Station. 85 p.

This report details how land cover and urbanization vary within the states of Delaware, Florida, Georgia, 

Maryland, North Carolina, South Carolina, Virginia, and West Virginia; and the District of Columbia by 

community (incorporated and census designated places), county subdivision, and county. Specifically 

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 benefits. 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, classified land cover, ecosystem services, 

urbanization

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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