United States 

Department of 

Agriculture

U.S. Forest 

Resource Facts 

and Historical 

Trends

Forest Service FS-1035 August 2014
2 U.S. Forest Resource Facts and Historical Trends

Editors

Sonja N. Oswalt | Resource Analyst

Forest Inventory and Analysis | USDA Forest Service

Southern Research Station | Knoxville, TN

W. Brad Smith | Associate National Program Manager

Forest Inventory and Analysis | USDA Forest Service

National Office | Washington, DC

Acknowledgments

In addition to acknowledging the main contributors 

listed on the contents page after each section title, the 

editors acknowledge the contributions made by the 

following people for their review and comments:

David Darr

Linda Langner

Patrick Miles

Mark Nelson

Charles (Hobie) Perry

Ken Skog

Jim Strittholt

Jeanine Paschke

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

national origin, age, disability, and where applicable, sex, marital 

status, familial status, parental status, religion, sexual orientation, 

genetic information, political beliefs, reprisal, or because all or 

part of an individual’s income is derived from any public assistance 

program. (Not all prohibited bases apply to all programs.) Persons 

with disabilities who require alternative means for communication 

of program information (Braille, large print, audiotape, etc.) should 

contact USDA’s TARGET Center at (202) 720-2600 (voice and 

TDD). To file a complaint of discrimination, write USDA, Director, 

Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410, or call (800) 795-3272 (voice) or (202) 720-

6382 (TDD). USDA is an equal opportunity provider and employer.

The use of trade or firm names in this publication is for reader information and does not imply endorsement by the U.S. Department 

of Agriculture of any product or service.
U.S. Forest Resource Facts and Historical Trends 3

Contents

Introduction..............................................................4

W. Brad Smith

Forest Inventory and Other Data...........................5

W. Brad Smith

The United States in a Global Context...................6

Sonja Oswalt

Land and Forest Area..............................................7

Sonja Oswalt, W. Brad Smith

Reserved Forest......................................................10

Sonja Oswalt

Timber Land and Other Forest ............................10

Sonja Oswalt, W. Brad Smith

Urban Associated Forest........................................ 11

David Nowak

Forest Ownership...................................................13

Brett Butler

Fragmentation of Forests......................................17

Kurt Riitters

Forest Age and Composition.................................20

Sonja Oswalt

Forest Carbon and Biomass..................................27

Grant Domke, Chris Woodall

Forest Health and Invasive Species......................29

Chris Oswalt, Sonja Oswalt, Frank Sapio

Wildland Fire..........................................................34

National Interagency Fire Center

Timber Products and Harvesting .........................36

James Howard, Brad Smith

Nontimber Forest Products...................................42

Jim Chamberlain

Ecosystem Services.................................................44

Evan Mercer

Water Supplies .......................................................46

Tom Brown

Forest Wildlife ........................................................48

Curt Flather

Recreational Use of Forests...................................50

Ken Cordell, Shela Mou

Forests of the Caribbean and Pacific Islands......53

Tom Brandeis, Joe Donnegan

Terms.......................................................................55

References...............................................................58

Web Resources........................................................61
4 U.S. Forest Resource Facts and Historical Trends

Introduction

The Resources Planning Act (RPA) Assessment Update for 2015 is being prepared in response to the 

mandate in the Forest and Rangeland Renewable 

Resources Planning Act of 1974, P.L. 93-378, 88 

Stat. 475, as amended. The update consists of a 

summary report and a data CD (compact disk). The 

report is available for download at http://www.fs.fed.

us/research/rpa. Hard copies of the report and data 

CD are also available for order at that location. 

The National Report on Sustainable Forests provides 

the most comprehensive account of available data on 

the current condition of the Nation’s forest resources. 

The report is based on 58 indicators for the conservation and sustainable management of forests. The 

United States and 11 other countries that house 90 

percent of the Earth’s temperate and boreal forests 

and 60 percent of all forests endorsed the indicators. 

Information on this report may be found on the Web 

at http://www.fs.fed.us/research/sustain/.

This brochure provides selected highlights of the 

findings of both assessments. Much of the data for 

this brochure is reported regionally as North, South, 

and West. In some cases, North and South are combined into a category labeled “East.”

WEST 

NORTH 

SOUTH 

Major U.S. reporting regions for this brochure.
U.S. Forest Resource Facts and Historical Trends 5

Forest Inventory and Other Data

The Forest Inventory and Analysis (FIA) program of 

the Forest Service, an agency of the U.S. Department 

of Agriculture (USDA), conducts inventories of the 

attributes of forest resources and reports them in the

RPA Assessment and various supporting documents. 

The FIA program has been conducting field inventories for more than 80 years, using state-of-the art

technology to provide estimates of the status, condition, 

and trends of the Nation’s forests. These estimates 

are critical to the development and implementation 

of policies and practices that support sustainable 

forestry in the United States. Since 1953, 10 national 

reports based on FIA data have been produced.

Extensive field measurements from FIA inventories 

include more than 4.5 million remote sensing plots 

interpreted for land use; more than 125,000 permanent field plots systematically located across all U.S. 

forest lands; more than 100 characteristics measured 

at each plot location; and more than 1.5 million trees 

measured to evaluate volume, condition, and vigor.

Data for forest ownership and products are from 

periodic FIA forest ownership and products studies. 

Data for wildlife, recreation, health, timber trade, and 

nonwood products were derived from Forest Service 

scientists’ contributions to the National Report on 

Sustainable Forests—2010 and 2015. Web sources 

for that report and other related data appear in the 

Web Resources section at the end of this brochure.

This brochure is available in five languages: English, 

Chinese, French, Russian, and Spanish. Visit the FIA 

Web site at http://fia.fs.fed.us to obtain copies.
6 U.S. Forest Resource Facts and Historical Trends

The United States in a Global 

Context

Global forestry issues are of considerable significance to the United States, which has 5 percent of 

the Earth’s population and consumes an estimated 28 

percent of the Earth’s industrial wood products. Although domestic timber inventory is only 10 percent 

of the Earth’s total, 96 percent of U.S. consumption 

of industrial wood comes from domestic supplies. 

Additional demands on U.S. forests are also of interest and include protected areas for biodiversity and 

relative contributions of U.S. forests to carbon pools, 

among others.

Timber used for

0% 10% 20% 30%

industrial products

Timber inventory

Woody biomass

Forest land

Land area

Population 5%

7%

8%

6%

10%

28%

The United States as a percent of world totals for 

selected measures.

thinkstockphotos.com
U.S. Forest Resource Facts and Historical Trends 7

Land and Forest Area

In 1630, the estimated area of U.S. forest land was 

1,023 million acres or about 46 percent of the total 

land area. Since 1630, about 256 million acres of forest land have been converted to other uses—mainly 

agricultural. Nearly two-thirds of the net conversion 

to other uses occurred in the second half of the 19th 

century, when an average of 13 square miles (mi2

) of 

forest was cleared every day for 50 years. By 1910, 

the area of forest land had declined to an estimated 

754 million acres, or 34 percent of the total land area. 

In 2012, forest land comprised 766 million acres, or 

33 percent of the total land area of the United States. 

Forest area has been relatively stable since 1910, although the population has more than tripled since then.

0

50

100

150

200

250

300

350

-

100

200

300

400

500

600

700

800

900

1,000

1850 1880 1910 1940 1970 2000

Million persons

Million acres

Forest area Population

Forest area and population trends in the United 

States, 1850–2010.

Stable forest area, however, does not mean that the 

character of the forest has not changed. In addition to 

reversions to and from agriculture and more intensive 

land uses like urban development, forests respond to 

human manipulation, aging, and other natural processes. The effects of these changes are reflected in 

the information presented in this brochure.
8 U.S. Forest Resource Facts and Historical Trends

Land and forest area trends in the United States1.

Category Year Region

U.S. North South West

Million acres

Land 2012 2,261 413 533 1,315 

Of which:

Forest 2012 766 176 245 346

2007 752 172 235 346

1997 742 170 231 341

1987 733 165 234 333

1977 742 164 235 343

1963 753 166 245 342

1953 742 161 240 341

1940 738 159 232 346

1920 721 149 220 353

Of which:

Timber land 2012 521 167 210 144 

2007 514 164 204 146 

1997 504 159 201 143 

1987 485 155 195 135 

1977 491 153 198 139 

1963 515 156 209 150 

1953 509 154 205 150 

1940 502 149 200 153 

1920 482 138 194 149 

Reserved 

forest2 2012 74 7 4 63 

2007 75 6 3 65 

1997 52 8 4 40 

1987 35 7 3 25 

1977 29 6 2 21 

1963 25 4 1 19 

1953 24 4 1 19 

1940 11 4 0 6 

1920 10 3 0 6 

Other forest 2012 187 17 31 139 

2007 162 2 7 134 

1997 187 3 9 157 

1987 211 4 13 173 

1977 215 5 17 182 

1963 216 5 18 173 

1953 217 3 20 172 

1940 233 6 21 187 

1920 238 7 18 197 
U.S. Forest Resource Facts and Historical Trends 9

Land and forest area trends in the United States 

(continued).

Category Year Region

U.S. North South West

Million acres

Woodlands 

(nonforest, 

see definition)

2012 53 - 23 30 

Total forest 

and woodlands

2012 819 176 267 376 

1

In addition to land area of the United States at that time, 

estimates for 1920 and 1938 include forest area in the regions 

that would become the States of Alaska and Hawaii. Estimates 

for 1630 represent the forest area in North America for regions 

that would become the 50 States within the current United 

States. (Source for 1938: U.S. Congress [1938].) (Source for 

1907 and 1630: R.S. Kellogg [1909]).

2

Does not include some protected areas. National forest 

roadless areas are International Union for Conservation of 

Nature (IUCN) Class VI but not identified as “reserved” in 

Forest Inventory and Analysis program (FIA) statistics and 

total approximately 32 million acres. These lands are currently 

reported in timber land and other forest land in FIA reports. 

New inventories will provide more accurate data to place these 

lands in their proper IUCN classification.

Forest Service
10 U.S. Forest Resource Facts and Historical Trends

Reserved Forest 

Of the total forest land, 10 percent are classified as

reserved. This classification indicates that these forest

lands are not managed for timber harvest, which is

prohibited by law on these lands in most cases. Reserved forests have changed very little since 2007, 

with a very small (2 percent) reduction in area. Nationwide, reserved forest area is more than three times 

what it was only 59 years ago. Most reserved land is 

in the West, reflecting a larger proportion of publicly 

owned land in that region. In general, U.S. private 

forest land is classified as “timber land” by FIA, even 

if landowners do not intend to harvest timber.

0

10

20

30

40

50

60

70

80

1953 1963 1977 1987 1997 2007 2012

Million acres

Year

West

South

North

Trends in reserved forest land, by region, 1953–2012.

Timber Land and Other Forest 

The South contains 40 percent of the Nation’s 521 

million acres of timber land. In contrast, the West 

constitutes only 28 percent of national timber land, 

and the North 32 percent. The South is often referred 

to as the “woodbasket” of the United States because 

of the extensive timber supply, while the West is host 

to most of the Nation’s reserved forest and national 

parks. Other woodlands, including scrub forests, are 

found in the highest concentrations in the West and 

South, with none meeting that definition in the North.
U.S. Forest Resource Facts and Historical Trends 11

0

100

200

300

400

West South North

Million acres

Timber land Reserved forest

Other forest Other wooded land

Forest land, by class and region, 2012.

Urban Associated Forest

Urban land in the coterminous United States increased 

from 2.5 percent of total land area in 1990 to 3.1 percent 

in 2000 to 3.6 percent in 2010. Urbanization affects 

the forest resource and its management in many 

ways. Not only does urban development eliminate 

some trees and forests, it also increases population 

density, human activities, and urban infrastructure, 

which can affect forests and their management. As urban landscapes increase across the Nation, rural forest 

landscapes are often converted to developed lands. 

With more than 80 percent of the U.S. population 

living in urban areas, ecosystem services provided by 

urban trees and forests are significant and valued in 

billions of dollars annually.

Nationally, urban areas (population density of at 

least 500 people/mi2

) have an average tree cover 

of 35 percent (Nowak and Greenfield 2012a); with 

tree cover in urban areas on the decline (Nowak and 

Greenfield 2012b) and most urban tree cover established through natural regeneration (Nowak 2012). 
12 U.S. Forest Resource Facts and Historical Trends

In the United States, an estimated 4 billion urban 

trees provide many valuable benefits based on their 

current composition and function. Besides the basic 

value of the trees—estimated at $2.4 trillion (Nowak 

et al. 2002), additional benefits of urban trees include 

air-pollution removal and carbon sequestration. Annual pollution removal (ozone, particulates, nitrogen 

dioxide, sulfur dioxide, and carbon dioxide) by urban 

trees is estimated at 711,000 metric tons ($3.8 billion 

value, according to Nowak et al. 2006) and storage 

of 643 million metric tons of carbon ($50.5 billion 

value) with a gross carbon sequestration rate of 25.6 

million metric tons C per year ($2.0 billion per year) 

(Nowak et al. 2013).

One coarse measure of the expanding urban influence 

on forests is a simple classification of forest area by 

county based on population demographics. The following graphic demonstrates that the area of forest in 

rural counties (no population centers with more than 

2,500 people) in the past 15 years has declined by 

48 million acres (17 percent). That is, the number of 

counties with small populations, and their associated 

forest areas, has declined.

-

50

100

150

200

250

EAST WEST EAST WEST EAST WEST

Forest land in 

counties with 

urban centers 

over 20,000 

persons

Forest land in

counties with

urban centers 

of 2,500 

to 20,000 

persons

Forest land in

counties with 

no urban 

center greater 

than 2,500 

persons

Million acres

1997 2012

U.S. forest land area, by population influence, 1997 

and 2012.
U.S. Forest Resource Facts and Historical Trends 13

Forest Ownership

U.S. forest ownership patterns are quite diverse 

with public forests dominant in the West and private forests dominant in the East. Private industrial 

forest ownership is concentrated in the South, Pacific 

Northwest, upper Lake States, and northern New 

England.

Private Public 

U.S. forest land ownership, 2012. (Alaska [not pictured] has 126 million acres of forest that is 72-percent public ownership and Hawaii [not pictured] has 

1.7 million acres of forest that is 34-percent public 

ownership.)

thinkstockphotos.com
14 U.S. Forest Resource Facts and Historical Trends

U.S. forest land, by ownership class, 2012.

Owner class/

land class

Region

U.S. North South West

Million acres

All owners 766 176 244 346 

 Timber land 521 167 210 144 

 Reserved forest 74 7 4 63 

 Other forest 172 2 31 139 

National Forest 145 12 13 120 

 Timber land 98 10 12 75 

 Reserved forest 27 1 1 24 

 Other forest 20 0 0 20 

Other public 176 35 20 122 

 Timber land 63 29 15 19 

 Reserved forest 47 5 3 39 

 Other forest 67 0 2 65 

Private corporate 147 29 65 53 

 Timber land 111 29 61 21 

 Reserved forest 0 - 0 0 

 Other forest 36 0 4 32 

Private noncorporate 298 100 147 51 

 Timber land 249 99 121 28 

 Reserved forest 0 0 0 0 

 Other forest 48 1 25 22 

Public Forests

The Federal Government predominantly owns public 

forest lands in the West and State and county governments own most of the public lands in the East. Of all 

public forest acres, 75 percent are in the West. Most 

protected forests are in public ownership while most 

production forests are in private ownership.
U.S. Forest Resource Facts and Historical Trends 15

Private Forests

Private ownership accounts for 56 percent of total 

forest land. More than 10 million individual and family forest landowners own 42 percent of total forest 

land, representing a diverse group of people who 

have many reasons for owning their forest land. Most 

of this family-owned forest is used for the aesthetics 

that forests provide, as habitat for wildlife, and as 

part of a family legacy. Corporations, partnerships, 

and tribes own most of the remaining 14 percent of 

privately owned U.S. forests.

Public

70%

Private

30%

Forest ownership in the Western United States.

Public

19%

Private

81%

Forest ownership in the Eastern United States.
16 U.S. Forest Resource Facts and Historical Trends

Management and Harvest

Removals have shifted in recent years from public 

lands in the West to private lands in the East. As the 

emphasis on timber production shifts from public 

to private lands, the need for information on the 

management objectives and behaviors of the private 

forest land owners has increased. This information is 

critical for informing U.S. policies promoting sustainable forestry. Recent studies show that only 8 percent 

of the families and individuals who own U.S. forest 

land have a written management plan. Those owners 

with plans manage 24 percent of the total forest land 

owned by these groups, however.

24%

8%

0%

Percent of individual

and family forest

ownerships with a

written management plan

Percent of individual

and family forest

land with a written

management plan

10% 20% 30%

Percent of individual and family forest owners and 

percent of family owned land with management plans.

Private forests provided 88 percent of the Nation’s 

timber harvest in 2011. A recent survey indicated that 

people who commercially harvested trees own nearly 

two-thirds of private forest land. Most private forest 

land area owners have 100 acres or more of forest land 

while most individual owners have less than 10 acres.

Landowner Characteristics

Private forest land holdings that are smaller than 50 

acres make up 25 percent of total privately owned 

forest lands. The small size of most family forests has 

implications for what landowners can do with their 

land. In addition, characteristics such as reasons for 

owning forest land are highly correlated with size.

People 75 years old or older currently own 20 percent 

of family forest land, and people between 65 and 74 
U.S. Forest Resource Facts and Historical Trends 17

years old own an additional 28 percent. This relatively advanced ownership age portends the transfer of a 

substantial amount of forest land in the near future.

Industrial Forests

Corporations that own forest land with woodprocessing facilities traditionally have been a major 

source of U.S. timber production. In 2001, the forest 

industry owned 66 million acres (13 percent) of the 

Nation’s 504 million acres of timber land but supplied 29 percent of wood production.

Recent changes in corporate strategies have shifted 

the traditional view of industrial forests, however. 

Many forest industry companies have divested some 

or all of their forest land holdings in the past 20 

years. Some of these lands were acquired by timber 

investment management organizations, and families 

and individuals purchased other lands.

0

5

10

15

20

25

30

35

40

45

 1-9 10-49 50-99 100-

499

 500-

999

 1000+

Percentage of private 

forest land

Parcel size (acres)

1994 2006 2012

Trends in private forest area, by size of landholding in 

the coterminous United States.

Fragmentation of Forests

The Forest Service uses land cover maps derived 

from high-resolution satellite imagery to determine 

how much forest land is subject to different types and 

degrees of fragmentation. Human activities and natural processes cause fragmentation that may lead to the 

isolation and loss of species and gene pools, degraded 
18 U.S. Forest Resource Facts and Historical Trends

habitat quality, and a reduction in the forests’ ability 

to sustain the natural processes that are necessary to 

ecosystem health. The fragmentation of forest area 

into smaller pieces changes ecological processes and 

alters biological diversity.

Analysis of fragmentation is scale dependent and 

consequently differs depending on whether the geographic context is large or small. In the United States, 

areas that are forested tend to be clustered in proximity to other places that are forested, but blocks of 

forest land are usually fragmented by inclusions of 

nonforest land. This clustering pattern is repeated 

across a wide range of spatial scales.

An overall measure of fragmentation is the proportion of the existing forest that is “interior,” that is, a 

forest parcel embedded in a 40-acre landscape that 

has at least 90-percent forest land cover. Recent data 

permit analysis of trends in interior forest area from 

2001 to 2006. Changes in total forest cover do not 

necessarily translate directly to changes in interior 

forest cover because of the unique relationship between forest cover, initial conditions, and adjacent or 

embedded land use.

Between 2001 and 2006, the coterminous United 

States experienced a net loss of 1.2 percent of its total 

forest cover. In comparison, the net loss of interior forest between 2001 and 2006 was 4.3 percent. 

Forest cover losses tended to occur in or near interior 

forests, while forest land cover gains did not tend to 

create new interior forest.

The following figure compares the net percent change 

in total forest land cover area (top) with net percent 

change in interior forest area (bottom). For most 

counties, relatively small percent change in total forest land cover area translated to larger percent change 

in interior forest area. Relatively few counties experienced increases in interior forest area, and interior 

forest area was reduced even in some counties that 

experienced increases in total forest area.
U.S. Forest Resource Facts and Historical Trends 19

Net area change

All forest land cover

Interior forest land cover

>1% gain

<1% loss

1% to 4% loss

5% to 8% loss

9% to 12% loss

>12% loss

Percent change in total forest land cover area and 

interior forest area, by U.S. county, 2001 to 2006. 

White indicates no interior area.

Note: This analysis of forest cover change does not 

correlate directly to forest area change because of 

the difference between forest cover and forest land 

use. Forest cover loss computed using remotely 

sensed data may include areas such as timber harvest that will reforest in the future because satellite 

imagery cannot infer land use. Forest area values 

reported using ground sampling continue to report 

regenerating harvest land as forest because the land 

hasn’t changed.
20 U.S. Forest Resource Facts and Historical Trends

Forest Age and Composition

Predominate U.S. timber stand age varies by region. 

In the South, where more acres of short-rotation yellow pine trees are planted, 51 percent of timber land 

is less than 40 years old compared with 20 percent in 

the North and 22 percent in the West. In contrast, 56 

percent of northern timber land is more than 60 years 

old, compared with 27 percent in the South and 69 

percent in the West.

South North

West

0%

1%

2%

3%

4%

5%

6%

7%

8%

9%

10%

5

203550658095

110125140

151-175

300+

Percent of region’s total forest land

Stand age (years)

Distribution of forest land by region and stand age, 

2012.

U.S. forests reflect a diversity of landforms and precipitation patterns. In the East, deciduous hardwoods 

and yellow pines prevail. Rapidly reproducing maples 

have seen an uptick since 1977, while in the South 

longleaf-slash pine forests have seen a decline. In the 

West, hemlock-Sitka spruce forests and ponderosa 

pine have declined since 1977, while western pine 

forests have increased. Researchers spend a great deal 

of time studying changing U.S. forest systems and the 

potential impacts to the economy and environment.
U.S. Forest Resource Facts and Historical Trends 21

0 20 40 60 80 100 120

Northern conifers

Longleaf-slash pine

Loblolly-shortleaf pine

Oak-hickory-North

Oak-hickory-South

Oak-pine

Oak-gum-cypress

Elm-ash-cottonwood

Maple-beech-birch

Aspen-birch

Other forest types

Million acres

1977

2012

Forest type trends in the East, 1977 to 2012.

0 20 40 60 80 100 120

Douglas-fir

Ponderosa pine

Fir-spruce

Hemlock-Sitka spruce

Lodgepole pine

Other softwoods

Western hardwoods

Million acres

1977

2012

Forest type trends in the West, 1977 and 2007.

U.S. forests are predominantly natural stands of 

native species. Planted forest land is most common in 

the East and consists primarily of planted native pine 

stands in the South. In the West, planting is generally 

used to augment natural regeneration.
22 U.S. Forest Resource Facts and Historical Trends

0 20 40 60 80 100

East

West

Percent

Natural Planted

Origin of U.S. forest stands.

U.S. forest planting averages about 2 million acres 

per year. Yellow pine in the South accounts for the 

largest area of single-species planting. The Soil Bank 

Program spiked forest planting in the South in the 

1950s, and in the 1980s, the Conservation Reserve 

Program planted nearly 3 million acres of nonforest 

land. In recent years, western U.S. forest planting has 

subsided, a trend that mirrors reduced harvesting in 

that region.

North

South

West

0.0

0.5

1.0

1.5

2.0

2.5

3.0

192819361947195419611968197519821989199620032010

Million acres

U.S. forest planting, 1952–2011.

Forest Service
U.S. Forest Resource Facts and Historical Trends 23

Growing Stock Volume

U.S. timber land growing stock inventory, growth, removals, and mortality, by region and species group, 

1952–2012.

Volume 

category Year Region

U.S. North South West

All species Million cubic feet

Inventory 2012 972,395 267,803 306,623 397,968

2007 932,089 248,005 288,521 395,563

1997 835,669 214,246 256,359 365,063

1987 781,656 190,038 244,641 346,977

1977 733,056 163,008 223,373 346,675

1963 665,600 128,288 174,072 363,240

1953 615,884 103,748 148,470 363,666

Growth 2011 26,413 6,516 13,809 6,088

2006 26,744 6,576 13,272 6,896

1996 23,577 5,420 10,712 7,445

1986 22,636 5,512 9,986 7,138

1976 21,237 5,349 11,323 4,565

1962 16,705 4,424 8,093 4,188

1952 13,910 3,716 6,683 3,511

Removals 2011 12,854 2,360 8,048 2,446

2006 15,533 2,820 9,696 3,017

1996 16,021 2,772 10,185 3,064

1986 16,451 2,708 8,699 5,044

1976 14,229 2,659 6,571 4,999

1962 11,959 2,078 5,525 4,357

1952 11,451 2,198 5,489 3,765

Mortality 2011 11,262 2,481 5,102 3,679

2006 10,281 2,335 4,981 2,966

1996 7,814 1,628 3,730 2,456

1986 5,677 1,243 2,705 1,730

1976 5,074 1,149 2,259 1,666

1962 5,129 940 1,965 2,225

1952 4,509 690 1,576 2,242
24 U.S. Forest Resource Facts and Historical Trends

U.S. timber land growing stock inventory, growth, removals, and mortality, by region and species group, 

1952–2012 (continued).

Volume 

category Year Region

U.S. North South West

Softwoods Million cubic feet

Volume 2012 547,619 58,761 128,956 359,902 

2007 529,195 55,864 118,472 354,859 

1997 483,837 49,372 104,844 329,621 

1987 467,575 47,618 105,613 314,344 

1977 466,960 43,850 101,208 321,902 

1963 449,760 33,661 75,087 341,012 

1953 431,794 27,053 60,462 344,279 

Growth 2011 15,663 1,512 8,808 5,344 

2006 15,241 1,489 7,632 6,120 

1996 13,284 1,169 5,889 6,225 

1986 13,007 1,288 5,499 6,220 

1976 11,910 1,558 6,315 4,037 

1962 9,610 1,211 4,699 3,700 

1952 7,735 973 3,641 3,120 

Removals 2011 8,319 640 5,335 2,345 

2006 9,859 677 6,317 2,865 

1996 10,065 668 6,478 2,918 

1986 11,367 726 5,741 4,901 

1976 10,046 705 4,471 4,870 

1962 7,624 540 2,812 4,272 

1952 7,542 712 3,078 3,753 

Mortality 2011 5,162 564 1,248 3,350 

2006 4,491 547 1,288 2,657 

1996 3,626 456 1,036 2,135 

1986 2,782 368 841 1,573 

1976 2,466 324 632 1,510 

1962 2,769 293 399 2,077 

1952 2,662 216 333 2,113 
U.S. Forest Resource Facts and Historical Trends 25

U.S. timber land growing stock inventory, growth, removals, and mortality, by region and species group, 

1952–2012 (continued).

Volume 

category Year Region

U.S. North South West

Hardwoods Million cubic feet

Volume 2012 424,776 209,043 177,667 38,066 

2007 402,894 192,141 170,049 40,704 

1997 351,832 164,874 151,515 35,442 

1987 314,081 142,420 139,028 32,633 

1977 266,096 119,158 122,165 24,773 

1963 215,840 94,627 98,985 22,228 

1953 184,090 76,695 88,008 19,387 

Growth 2011 10,750 5,004 5,002 744 

2006 11,503 5,087 5,640 776 

1996 10,294 4,251 4,823 1,220 

1986 9,629 4,224 4,487 918 

1976 9,327 3,791 5,009 528 

1962 7,095 3,213 3,394 488 

1952 6,175 2,743 3,041 391 

Removals 2011 4,535 1,720 2,714 101 

2006 5,675 2,143 3,379 152 

1996 5,956 2,104 3,707 146 

1986 5,083 1,983 2,958 143 

1976 4,183 1,953 2,100 129 

1962 4,336 1,538 2,713 85 

1952 3,909 1,486 2,411 12 

Mortality 2011 6,100 1,917 3,853 329 

2006 5,790 1,788 3,693 309 

1996 4,188 1,172 2,694 321 

1986 2,896 875 1,864 157 

1976 2,607 824 1,627 156 

1962 2,361 647 1,566 148 

1952 1,847 475 1,243 129 
26 U.S. Forest Resource Facts and Historical Trends

Average growing stock volume per acre continues 

to increase across the United States with the largest 

gains in the North and South where volumes per acre 

are nearly double what they were in 1953.

-

500

1,000

1,500

2,000

2,500

3,000

North South West U.S.

Cubic feet per acre

1953 1977

2007 2012

Volume per acre on timber land.

During the past 60 years, net growing-stock growth 

has consistently exceeded growing-stock removals 

in the United States. In terms of percent of standing 

volume, removals are at the lowest level in the past 

60 years and growth has also slowed. The volume of 

annual net growth is currently 2 times higher than the 

volume of annual removals. Mortality remains similar 

to 2006, at less than 1 percent of standing inventory.

-

0.5

1.0

1.5

2.0

2.5

3.0

3.5

195219621976198619962011195219621976198619962011195219621976198619962011

Growth Removals Mortality

Percent of inventory

Net growth, removals, and mortality rates for growing stock, 1952—2011.
U.S. Forest Resource Facts and Historical Trends 27

Forest Carbon and Biomass

Forest ecosystems are the largest terrestrial carbon sink 

on earth and their management has been recognized 

as a relatively cost-effective strategy for offsetting 

greenhouse gas emissions. The United States quantifies 

forest carbon stocks and stock changes in national and 

international reports using data from the national forest 

inventory administered by the Forest Service.

Forests in the United States continue to sequester more 

carbon than they emit each year, and combined with 

urban forest, and harvested wood products, offset nearly 

15 percent (955 tetragrams of carbon dioxide equivalent [Tg CO2

 eq.]) of total greenhouse gas emissions 

in 2012. An additional 270 Tg CO2 eq. was sequestered in forest ecosystems and subsequently emitted 

back to the atmosphere through wildfire combustion.

- 1,200

- 1,000

- 800

- 600

- 400

- 200

0 1990 2005 2008 2009 2010 2011 2012

Net annual change in C stocks

(TgCO2eq.)

Year

Urban forest

Harvested 

wood products

Litter

Dead wood

Belowground 

live trees

Soil organic matter

Aboveground 

live trees

Estimated net annual changes in carbon stocks in 

forest, urban forest, and harvested wood pools in the 

United States, 2012. Note that negative values indicate net carbon sequestration. (Sources: U.S. Department of Agriculture, Forest Service 2014a, EPA 2014)
28 U.S. Forest Resource Facts and Historical Trends

Forests in the United States store an estimated 43,126 

Tg carbon in live and dead biomass and soil organic 

matter. Forest ecosystems in the Pacific Northwest 

and Northern Lake States have the greatest carbon 

density, often in excess of 200 megagrams per hectare. 

Forests in Northeast, Intermountain West, along the 

Appalachian Mountains, and throughout the Southeast also contain substantial biomass that is distributed throughout the different ecosystem pools.

No estimate 

< 50 

50 – 100 

101 – 150 

151 – 200 

> 200 

Water 

Mg/ha 

Estimated forest ecosystem carbon density (megagrams per hectare) imputed from forest inventory 

plots, coterminous United States, 2001–2009: total 

forest ecosystem carbon (Source: Wilson et al. 

2013.) 

In addition to carbon fossil fuel for energy, forest 

biomass consumption for energy has declined during 

the past several years. Despite recent declines, however, wood energy plays a major role in U.S. forested 

regions and continues to comprise approximately 

2 percent of the total U.S. energy consumption.
U.S. Forest Resource Facts and Historical Trends 29

> 1,200 

600 – 1,200 

300 – 600 

100 – 300 

< 100 

Total aboveground 

live tree biomass (Tg)

> 10

5 – 10 

3 – 5 

1 – 3 

< 1 

Wood as a percent of 

total energy 

consumption 

Estimated total aboveground live tree biomass and 

wood energy as a percent of total U.S. energy consumption, 2012. (Sources: U.S. Department of Agriculture, Forest Service 2014a, EPA 2014)

Forest Health and Invasive Species

Mortality rates relative to inventory remain less than 

1 percent of standing inventory. Mortality rates in the 

South have declined since 2006, while they continue 

to rise in the West where mountain pine beetle affected millions of acres of forest between 2009 and 2010. 

Root diseases, bark beetles, and oak decline were the 

leading contributors to mortality risk in the coterminous United States (Krist and others 2014).
30 U.S. Forest Resource Facts and Historical Trends

0.00

0.20

0.40

0.60

0.80

1.00

1.20

U.S. North South West

Percent of inventory

1952 1976 2006 2012

Mortality as a percent of standing inventory.

Areas depicted in the following graphic are at potential risk of 25 percent or higher mortality because of 

insects and disease during the next 15 years.

77 million acres at risk 

Treed land at risk 

of high mortality 

Other treed land 

9.5 million acres at risk 0.4 million acres at risk 

National 2012 Composite Insect and Disease Risk 

Map (Source: U.S. Department of Agriculture, Forest 

Service 2014b)
U.S. Forest Resource Facts and Historical Trends 31

Aerial detection surveys provide information on the 

extent of major forest pest damage. Some of these 

pests include—

Southern pine beetle activity was at historically high 

levels throughout the past 20 years, which reflects 

the widespread availability of its preferred host, 

loblolly pine. Mortality from southern pine beetle has 

declined since a high in 2002.

40

20

0

1979 1994 2010

Million acres

Southern pine beetle

Mountain pine beetle activity was at an all-time high 

in 2009 and 2010 but showed a steady decline from 

2011 to 2012.

10

5

0

1979 1994 2010

Million acres

Mountain pine beetle
32 U.S. Forest Resource Facts and Historical Trends

Spruce budworm activity increased after the most recent Forest Facts update in 2006 but began to decline 

again in 2012.

12

10

8

6

4

2

0

1979 1994 2010

Million acres

Spruce budworm

Western spruce budworm defoliation peaked from 

1983 to 1992. Many trees weakened by budworm defoliation were subsequently killed by bark beetle attacks.

15

10

5

0

1979 1994 2010

Million acres

Western spruce budworm

Gypsy moths defoliated almost 13 million acres of 

hardwoods in 1980, and annual defoliation averaged 

2.8 million acres during the past 20 years. Gypsy moth 

activity reached unprecedented levels as it spread South 

and West into better habitat; the great reduction in recent years appears to reflect the effect of Entomophaga 

maimaiga (a fungal pathogen of the Gypsy moth).
U.S. Forest Resource Facts and Historical Trends 33

20

10

0

1979 1994 2010

Million acres

Gypsy moth

60

40

20

0

1979 1994 2010

Million acres

Total for the five insects

Dozens of diseases affect U.S. forests each year. The 

following table lists the 10 most common tree diseases in the United States.

Disease Primary species affected

beech bark disease beech

Dutch elm disease American elm

dogwood anthracnose dogwood

dwarf mistletoes conifers

fusiform rust southern pines

oak wilt eastern oaks

Port-Orford cedar root disease Port-Orford cedar

root rots many conifers and hardwoods

Sudden Oak Death California Oak, tanoak

white pine blister rust five-needle pines
34 U.S. Forest Resource Facts and Historical Trends

Expanding global trade and travel has increased 

the risk of introducing new and exotic organisms 

into forests. When introduced into new ecosystems, 

invasive species have no natural enemies and can 

therefore cause extensive damage. Invasive plant 

species are defined as species moved beyond their 

natural range or natural zone of potential dispersal, 

including all domesticated species and hybrids. The 

consequences of the introduction of invasive species 

can have major ecological and economic implications 

and may directly affect human health. One of the major effects of invasive species on biodiversity may be 

the loss of native species. An estimated 3,723 plants 

in the United States have origins outside the country. 

Areas with the highest rates of introduction tend to 

be along the coasts or major inland waterways. In 

general, human disruptions of natural communities, 

such as soil alterations, removal of vegetative cover, 

or suppression of natural disturbance regimes, seem 

to promote opportunities for invasive species.

Wildland Fire

Fire Condition Classes

Fire condition classes are a function of the degree 

of departure from historical fire regimes resulting 

in alterations of key ecosystem components such as 

species composition, structural stage, stand age, and 

canopy closure. Some of the activities that cause 

these departures include: fire exclusion, timber 

harvesting, grazing, introduction and establishment 

of exotic plant species, insects and disease (introduced or native), or other past management activities. 

Three general condition classes are identified based 

on four inputs: fire regimes relative to historic range, 

ecosystem stability relative to intact functioning 

components, fire frequency relative to historic range, 

and vegetation attributes (species composition and 

structure) relative to historic range.
U.S. Forest Resource Facts and Historical Trends 35

Moderate 

Non-burnable 

Very High 

High 

Wildland fire potential 2012

Very low 

Low 

Water 

Condition

class

Fire 

regime

Ecosystem

stability

Historic fire

frequency

Vegetation

attributes

1 Near normal High Within 1 

interval

Within 

historic range

2 Moderately

altered Moderate

Departure of 

more than 

one interval

Moderately 

altered from

historic range

3 Significantly

altered Low

Departure of 

multiple 

intervals

Significantly

altered from

historic range

Wildland fire potential in the coterminous United 

States, by risk class, 2012.

(Source: Fire Modeling Institute 2013)

Fuel Reduction

Years of fire suppression and other management 

practices have resulted in increased undergrowth and 

tree density (both live and dead) creating high fuel 

levels that have in turn contributed to high-intensity 

fires that have threatened property, natural resources, 

and the public. About 12 percent of coterminous U.S. 

forest land is currently at a high or very high risk for 

wildfire (http://www.firelab.org). In response to the 

risks posed by heavy fuel loads, the National Fire 

Plan (NFP) was established to provide a long-term 

program of hazardous fuels reduction on Federal and 

adjacent lands. The NFP emphasizes cooperation 

and collaboration among Federal agencies; State, 
36 U.S. Forest Resource Facts and Historical Trends

local, and tribal governments; and other stakeholders 

to achieve the fuel reduction goals and objectives. 

Reducing hazardous fuels lessens the risk to humans, 

important landscapes, and municipal watersheds as 

well as improving forest and rangeland health.

0

2

4

6

8

10

12

1960 

1965 

1970 

1975 

1980 

1985 

1990 

1995 

2000 

2005 

2010 

Million acres 

Annual area of wildland fire in the United States, 

1960–2011.

Wildland-Urban Interface

Wildland-urban interface (WUI) communities exist 

wherever homes and businesses are built among 

trees, brush, and other flammable vegetation. Historically aggressive and effective wildfire suppression 

has resulted in increased undergrowth and density of 

trees creating high levels of fuels. In these conditions, 

fires can move rapidly into the interface areas. A key 

element in reducing threats to these WUI areas and 

restoring fire to its natural role in the environment is 

community education and involvement. The Forest 

Service and the U.S. Department of the Interior agencies in partnership with the State foresters administer a 

variety of programs that address living with fire in the 

WUI.

Timber Products and Harvesting

According to the American Forest and Paper Association, the U.S. forest products industry employs about 

1 million workers and accounts for approximately 

6 percent of the total U.S. manufacturing gross 

domestic product, or GDP, placing it roughly on par 
U.S. Forest Resource Facts and Historical Trends 37

with the automotive and plastics industry. The forest 

products industry is among the top 10 manufacturing 

sector employers in 48 States and generates more 

than $200 billion a year in sales and about $54 billion 

in annual payroll. In 2011, it recovered 66.8 percent 

of paper consumed and is the leading generator and 

user of renewable energy.

Housing Market Effect on U.S. Forestry

The most significant event in recent years that affected the U.S. forest products industry was the collapse 

of the housing market and subsequent recession. The 

U.S. forest products industry experienced a downturn 

in output to its lowest level in decades. After record 

highs, a 75-percent drop in the number of singlefamily housing starts marked the nationwide housing 

market decline in 2005.

North

South

West 0

100

200

300

400

500

600

700

800

900

2001 2003 2005 2007 2009 2011

Thousand starts

Single-family housing starts, 2001–2011.

The housing situation, coupled with the movement of 

furniture production to other countries, contributed to 

sharp declines in solidwood-product output. Meanwhile, globalization of manufacturing and expanded 

use of electronic communication media contributed 

to a decline in U.S. pulp, paper, and paperboard 

output. Job losses in forestry and related economic 

sectors exceeded 1 million, or nearly 9 percent of 

all recession-related unemployment. Further fallout 

came with the temporary and permanent closure of 

nearly 1,000 wood-processing mills.
38 U.S. Forest Resource Facts and Historical Trends

Solid Wood and Paper

Solidwood and paper products consumed in the United States require both domestic and imported roundwood harvest, plus recycled paper and solidwood 

products. Since the early 1990s, roundwood harvest 

for export has declined, and roundwood equivalent of 

imports has increased. Domestic roundwood harvest 

increased from 1950 through the mid-1980s, peaking at 

15.6 billion cubic feet (ft3

) in 1989, and has remained 

steady until the recent economic downturn when 

roundwood harvest declined to 10.5 billion ft3 by 

2009. Roundwood harvest increased to 11.1 billion ft3

by 2011.

Exports 

Net imports 

- 

10 

20 

30 

40 

50 

60 

70 

80 

0

5

10

15

20

25 1965 

1970 1975 1980 1985 1990 1995 2000 2005 2010 

Cubic feet per capita 

Billion cubic feet 

Year 

Per capita consumption

Harvest for 

domestic use 

Total and per capita roundwood consumption, by 

category, 1965–2011.

Lumber

In 2009, lumber production hit the lowest level since 

1981 at 5.1 billion ft3 (30 billion board foot equivalent). This level has not been a normal production 

level since the 1950s. The early 1980s was a milder 

recession than the most recent one.
U.S. Forest Resource Facts and Historical Trends 39

North

South

All region 

production

All region

consumption

(gray area)

West

0

2

4

6

8

10

12

1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

Billion cubic foot equivalent

Year

Lumber production and total lumber consumption, 

by region, 1965–2011.

Pulpwood

While pulpwood production remained relatively stable during the recession, it had declined sharply in 

the late 1990s and today, like lumber, is at a nearly 

30-year production low at 4.5 billion ft3. While lumber was up in 2011, the pulp sector remained down.

North

South

All region 

production All region

consumption

(gray area)

West

0

1

2

3

4

5

6

7

1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

Billion cubic foot

Year

Pulpwood production and total pulpwood consumption, by region, 1965–2011.

Consumption, Imports, and Exports

Per capita consumption of wood and paper products 

in 2011 was 907 pounds (lb), down from 1,480 lb in 

2006. In addition, 157 lb of fuelwood was consumed 

per capita in 2011, a 20-percent reduction from 2006. 
40 U.S. Forest Resource Facts and Historical Trends

Net imports to the United States increased from 

slightly more than 1.0 billion ft3 in 1965 to 4.2 billion 

ft3 in 2005 before declining to slightly more than 

400 million ft3 in 2011. The large decline between 

2005 and 2011 was mostly the result of the economic 

recession that began in 2006. By 2011, net wood imports were less than 500 million ft3

. In 2005, the United States supplied 69 percent of the Nation’s timber 

needs. By 2011, this number increased to 79 percent 

while imports declined relative to total consumption.

Shifting Timber Harvest

Recent changes in public land policy have had significant impacts on private forests. As harvesting declined 

on public lands in the West, harvesting increased on 

private lands in the East, particularly in the South. 

Overall, domestic harvesting has remained steady to 

declining in the past decade, and increased imports 

and paper recycling supported increased demand.

Public

Private

0

5

10

15

20

1952 1962 1976 1986 1996 2001 2006 2011

Billion cubic feet

Year

Growing stock removals in the United States, by 

owner group, 1952–2011.

Harvest Methods and Efficiency

Timber harvests typically occur on about 11 million 

acres annually. Selective harvesting is prevalent on 

61 percent of harvested acres in the United States, 

and clearcutting occurs on the remaining 39 percent. 

Clearcutting is most prevalent in areas of managed 

plantations in the South and areas in the North where 

pioneer species such as aspen, jack pine, and 

spruce-fir—which need open sunlight to regenerate—

are being managed for timber production. In the West, 

clearcutting is generally followed by planting to augment natural regeneration. The recent recession not only 

reduced overall harvesting by 20 percent but also shifted 
U.S. Forest Resource Facts and Historical Trends 41

harvesting regimes toward more partial cutting as demand declined. The trend in increased partial cutting 

is slowly reversing and clearcutting is expected to return 

to about one-third of all harvesting in the United States.

- 20 40 60 80 100

2001-2005

2006-2011

2001-2005

2006-2011

2001-2005

2006-2011

North South West

Partial cut Percent of harvesting Clearcut

Proportion of harvested timber land in the United 

States by method of harvest for periods 2001–2005 

and 2006-2011

Logging Residues

Logging residues are portions of trees’ stems left behind after logging and are being increasingly considered by companies as a possible resource for bioenergy 

use. Overall, residues have ranged from an equivalent 

of 20 to 30 percent of the material taken for products 

and 15 to 20 percent of total harvest material. In 2011, 

logging residues totaled 3.7 billion ft3. Even after leaving a portion of residues for nutrient cycling and soil 

protection, residue volume has the potential to be 

a significant resource for wood energy.

0

5

10

15

20

25

Percent of harvested material

Total North South West

1952 1976 2011

Logging residues in the United States as a percent 

of total harvest, by region, 1952, 1976, and 2011.
42 U.S. Forest Resource Facts and Historical Trends

Nontimber Forest Products

The gathering of nontimber forest products is a 

significant use of the Nation’s forests that affects 

forest ecosystems and the economies of households 

and communities that depend on them. The products 

include herbal medicines, human and animal food, 

floral home decorative items, resins and oils for 

aromatics, arts and crafts, and furs for clothing. The 

harvest of these products from the Nation’s forests 

is significant for many Americans, who benefit from 

these products for their recreational, commercial, 

subsistence, and cultural values.

Herbal Medicines—The spiritual and physical 

healing of people around the world depends on native 

medicinal plants. During the past several decades, 

herbal medicinal products have had an unprecedented 

increase in demand, unlike many other nontimber forest products. The sale of herbal medicines provides 

much-needed income for rural harvesters and feeds a 

multibillion-dollar industry in the United States. The 

increased harvesting of this native flora has sparked 

concern for the long-term sustainability of this precious natural resource.

Food—Forest-foraged foods for urbanites is a phenomenon that may have an extraordinary impact on 

forest resources. This burgeoning industry depends 

on a steady and reliable source of native plants, some 

of which may only be available for a short time each 

year. Although forest-foraged foods may provide a 

small share of total U.S. food consumption, the cultural 

and ecological significance is tremendous. Hunting big 

game (large mammals), small game (rabbits, squirrels, 

etc.), and migratory game birds (ducks, geese, etc.) to 

put food on the family table has a long tradition in the 

United States. Healthy forage for livestock is particularly important in management of Federal lands.
U.S. Forest Resource Facts and Historical Trends 43

Floral Decoratives—Native plants harvested from 

U.S. forests for their aesthetic values adorn families’ homes, churches, and workplaces throughout 

the year. The U.S. floral industry uses thousands 

of pounds of greenery, leaves, twigs, and bark and 

millions of wild-harvested plants annually. A strong 

regional character of production and use persists, 

depending on species availability.

Aromatic Resins and Oils—Extracting essential oils 

from plants for commercial uses as fragrances has a 

long history in domestic and international markets.

Industrial chemists use aromatic compounds derived 

from native plants in air fresheners, bath and body 

products, inhalants, massage oils, perfumes, and food 

flavoring.

Arts and Crafts—Arts and crafts are an integral part 

of innumerable traditions: use of bark, willow, and 

branches in making baskets, masks, and traditional 

and ceremonial dress by Native Americans; dollmaking and basketweaving by crafts people in the Appalachians; and production of furniture, birdhouses, 

bowls, and other well-known and admired products.

Fur for Clothes—At one time, the harvest and trade 

in animals for their fur was a huge business. During 

the past 30 years, trapping animals for fur has declined sharply. This trend is expected to continue as 

consumer preferences change.

In general, nontimber forest product harvests go mostly undocumented, particularly on private forest lands. 

Few efforts to manage the harvest of these products as 

a natural resource have been made. Concern among 

scientists is growing for the conservation and sustainability of the native flora and fauna, because harvesting 

may have significant effects on forest ecosystems.
44 U.S. Forest Resource Facts and Historical Trends

Selling wild ramps at market. 

Jim Chamberlain, Forest Service

Ecosystem Services

Forests provide a variety of critical services to human 

societies, including carbon sequestration, water purification, and habitat for millions of species. Because 

forest landowners have traditionally not been paid for 

the services their land provides to society, financial 

incentives are usually too low to sustain production 

of services at optimal levels. To remedy this issue, 

a variety of public and private proposals to provide 

direct payments to landowners have emerged as a 

strategy to preserve, protect, and restore these ecosystem services.

Large-scale government payments for ecosystem services (PES) were initiated in the 1985 Farm Bill with 

the creation of the Conservation Reserve Program 

followed by the Wetlands Reserve Program, Forest 

Legacy Program, the Forest Stewardship Program, 

and the Stewardship Incentives Program in the 1990 

Farm Bill. Nearly 20 Federal programs currently pay 

private forest landowners to enhance ecosystem services through improved forest management, retention 
U.S. Forest Resource Facts and Historical Trends 45

of lands in forest or undeveloped uses, protection of 

soil and water quality, preservation of forested wetlands, and wildlife habitat improvement. In addition, 

many privately funded PES programs are operated in 

the United States. Conservation organizations have 

been paying forest landowners for decades (through 

conservation easements) to provide or protect ecosystem services. In addition, a thriving market has long 

existed comprising hunters purchasing the rights to 

access wildlife habitat and species through hunting 

leases with private landowners, especially in the South.

The National Report on Sustainable Forests will provide details on PES by Federal and State agencies as 

well as payments in the private sector. This brochure 

provides an overview of total Federal Government 

payments to private landowners from 2005 to 2011. 

Forest PES by the Federal Government increased 

about 53 percent from $340 million in 2005 to $520 

million in 2011. In 2007, Federal PES accounted for 20 

percent of all payments (public and private) to private 

forest landowners that would translate to total payments from all sources of about $2.6 billion in 2011.

0

100

200

300

400

500

600

700

2005 2006 2007 2008 2009 2010 2011

In millions of constant 2005 $

Bundled 

services

Biodiversity 

services

Water 

services

Federal payments to private forest landowners for 

ecosystem services, 2005–2011.

The distribution of payments among States for payments ecosystem services from the Federal Government 

in 2011 is shown in the following map. Connecticut 

landowners received the lowest payments ($149,000), 

while Florida landowners received the highest ($49 

million).
46 U.S. Forest Resource Facts and Historical Trends

Alaska Hawaii 

141 – 2,000 

2,001 – 6,000 

6,001 – 16,000 

16,001 – 35,000 

35,001 – 45,754 

Federal program payments in 2011 

(thousand constant 2005 $) 

Federal payments to private forest landowners for 

ecosystem services, by State, 2011.

Water Supplies

In the coterminous United States, 24 percent of the 

water supply originates on Federal land. Land owned 

by the Forest Service constitutes 18 percent of originating water sources. Regardless of ownership, about 

53 percent of the coterminous water supply originates 

on forest land. National forests and grasslands supply 

51 percent of the water supply in the West.

Water Uses

Estimates of U.S. freshwater use during 2005 

indicate that about 350 billion gallons per day were 

withdrawn for all uses. Since 1985, total freshwater 

withdrawals increased only 4 percent, while freshwater withdrawals have stabilized for the two largest 

uses—thermoelectric power and irrigation. In 2005, 

freshwater withdrawals for these two uses were each 

about 41 percent of total withdrawals. On a per capita 

basis, total freshwater withdrawals decreased by 16 

percent from 1985 to 2005.
U.S. Forest Resource Facts and Historical Trends 47

0

100

200

300

400

500

Billion gallons per day

1950 1960 1970 1980 1990 2000

Irrigation Thermoelectric

Other industrial Rural domestic 

Domestic and public and livestock

U.S. water uses, by type.

Watershed Management

Water quality is becoming an increasingly serious 

concern among scientists and policymakers in the 

United States, as well as globally. High-quality 

watersheds trap sediment and slow runoff, and they 

provide cooling shade and excellent habitat for wildlife, fish, and plants. Potential watershed management issues include habitat loss and fragmentation, 

hydrologic alterations, nutrient enrichment of surface 

waters, and pathogens and toxins. Forests offer significant mitigation opportunities for water management.

Effective watershed management must be based on 

a planning process that integrates both scientific 

analysis and public participation. Explore current 

efforts in watershed management at http://www.

partnershipresourcecenter.org/watersheds/index.php.

Drought

Many forests have had fires of unprecedented intensity and extent, and this situation is partially the result 

of forest management practices that have permitted 

decades of deadwood (fuels) to accumulate. These 

problems are exacerbated by climate variability in the 

form of prolonged periods of drought that have left 

forests in tinder-dry conditions, and thus more susceptible to intense fires. Public resource agencies are 

shifting their fire policies from complete suppression 

to recognition that fire is an integral component of the 

landscape. Presuppression forests experienced fires 
48 U.S. Forest Resource Facts and Historical Trends

more frequently, but these fires were less destructive 

than are those experienced post-suppression. These 

less intense fires served as a means of keeping fuels 

from accumulating on the forest floor and maintaining low stand density. The composite Palmer Drought 

Index shown in the following graphic indicates that 

much of the West is in a medium to high drought stage 

and patchy areas of the East are also at heightened risk.

Extreme drought

Severe drought

Moderate drought

Moderately moist

Very moist

Extremely moist

Mid-range

Palmer Hydrological Drought Index Long-term Conditions, 2014 (National Oceanic and Hydrological 

Administration) 

Forest Wildlife

Species Richness

A count of species is a basic and easily understood 

measure of biological diversity. The following 

species richness graphic shows where diversity is 

relatively high or relatively low based on recorded 

occurrences and geographic ranges of species and 

their intersection with ecoregional boundaries. Data 

on the distribution of 9,195 vascular plants and 1,165 

vertebrate species associated with forest habitats indicate notable differences in the number of species that 

can be supported across major U.S. ecoregions. The 

number of forest-associated species is highest in the 

Southeast, the arid Southwest, and the Mediterranean 

climate regions of coastal California.
U.S. Forest Resource Facts and Historical Trends 49

809–818 

819–1,726 

1,727–2,099 

2,100–2,436 

2,439–3,032 

Number of species 

Geographic variation in the number of forestassociated species occurring within ecoregions for 

all taxa. (Alaska and Hawaii are shown at a difference scale for presentation.)

Wildlife Trends

Recent historical wildlife trends have varied depending on the species. A general pattern of increasing 

populations and harvests has been observed among 

big game and waterfowl species. For many smallgame species, particularly among upland game birds, 

populations and harvests have seen declines. Among 

species that are not consumptively taken for sport, 

subsistence, or profit—what are generally referred 

to as nongame—we lack comprehensive monitoring 

data. A notable exception is breeding birds. For the 

426 species with sufficient data to estimate nationwide trends, 45 percent had stable abundances since 

the mid-1960s. Among bird species with evidence for 

an abundance trend, more had declining trends (31 

percent) than increasing trends (24 percent). Recent 
50 U.S. Forest Resource Facts and Historical Trends

U.S. trends in species of conservation concern indicate that overall biodiversity has continued to erode. 

Since 2000, 278 species became formally listed as 

threatened or endangered, with the greatest increases made among plants, fish, insects, mollusks, and 

amphibians.

Recreational Use of Forests

Recreation activities are increasingly important as 

a source of forest-based employment and income. 

Engaging in outdoor recreation and tourism in forests 

tends to build support among participants for protecting and managing forests, indirectly building support 

for sustainable forests. 

Twenty-six forest recreation activities have been 

inventoried (Bowker et al. 2012; Cordell 2012), and 

those with the greatest numbers of visits are walking 

for pleasure, viewing/photographing natural scenery, 

viewing/photographing forest vegetation, bird watching, watching wildlife, hiking, visiting wild areas, 

off-highway driving, family gatherings, and visiting 

nature centers. The indexed number of recreation 

activity days for these activities ranges from more 

than 8.5 billion (walking for pleasure) to just under 

760 million (visiting nature centers, etc.). Snowmobiling, mountain climbing, cross-country skiing, rock 

climbing, and snowshoeing account for much smaller 

numbers of activity days (ranging between about 19 

to 63 million). Americans appear to be strongly interested in viewing and photographing forest natural 

life. (The index of recreation activity days measures 

all incidents of participation in an activity across the 

population and days of the year and places.) Across 

all activities, the estimated percentage of recreation 

activity days that occur in urban forests ranges between 16 and 45 percent. The lowest percentages in 

urban forests are activities such as hunting, camping, 

and backpacking. The highest percentages in urban 

forests include activities such as walking, picnicking, 

family gatherings, and visiting nature centers.
U.S. Forest Resource Facts and Historical Trends 51

Annual forest recreation days* by activity, and estimated percentages in public and urban forests, 

2007–15.

Forest 

recreation 

activity 

(million 

days)

2007/ 

2008

2015 

projected

Percent 

change

Percent 

on 

public 

forests

Percent 

on 

urban 

forests

Walk for 

pleasure 7,493 8,504 14 54 45 

View natural 

scenery 6,171 6,596 7 62 32 

View/photograph birds 3,738 4,060 9 51 38 

View other 

wildlife 3,087 3,300 7 58 32 

Day hiking 1,235 1,360 10 76 34 

Visit wilderness areas 948 1,007 6 76 25 

Off-highway 

driving 838 892 7 50 23 

Mountain 

biking 463 355 (23) 60 32 

Picnicking 456 490 8 68 44 

Developed 

camping 356 383 8 73 21 

Big game 

hunting 280 286 2 46 17 

Backpacking 199 211 6 79 22 

Visit historic 

Sites 183 203 11 60 39 

Horseback 

on trails 178 193 9 51 34 

Cross country skiing 42 40 (4) 61 34 

* Recreation activity day = recreation in each activity equivalent to the activity completed by one person in one day.

Sources: 2007–08 NSRE data were used to estimate percentages of visits on public and urban forests. NSRE is the National 

Survey on Recreation and the Environment. Projections to 

2015 were from Bowker et al 2012 (http://www.treesearch.

fs.fed.us/pubs/40935). 
52 U.S. Forest Resource Facts and Historical Trends

The baseline values (2007/08) were taken from the 

National Report on Sustainable Forests, 2010. The 

2015 estimates were derived using projections provided in Bowker et al.’s (2012) and rates published in 

Cordell (2012) for activities not covered by Bowker. 

The following figure summarizes annual activity days 

of forest recreation across the activities shown above 

in the previous table. In 2008, the estimated index 

of total days was 33.3 billion. (This index reports 

billions because individuals across the U.S. population can participate in a number of different activities 

in many places on any given day, 365 days a year). 

Projected for 2015, the total activity days is 36.2 

billion, a forecast of an overall percentage increase of 

8.7 percent. In this same period, population increases 

by 6.18 percent, from almost 303 million in 2008 to a 

forecast of 321 million in 2015. Activity participation 

is projected to increase at a somewhat greater rate 

than population by 2015. Percentages projected to 

rise fastest are gathering mushrooms/berries, walking 

for pleasure, visiting historic/prehistoric sites, and 

mountain/rock climbing. Projected to decline were 

mountain biking and snowmobiling. Billions of days

Population in millions

38

2008

+6.18%

302.7

321.2

36.2

33.3

8.71%

2015

34

30

325

300

275

250

Number of recreation activity days (billions)

Population (millions)

Per capita 

activity days

2008 2015

110 112.7

Trend in population (in millions) and annual forest 

recreation activity days (in billions), 2008 to 2015.
U.S. Forest Resource Facts and Historical Trends 53

Forests of the Caribbean and 

Pacific Islands

The U.S. Caribbean Islands are composed of Puerto 

Rico and the U.S. Virgin Islands. In general, the Caribbean Islands are a 3,900-mile (mi) arc of islands, 

tectonically uplifted from the sea floor separating the 

Atlantic Ocean from the Caribbean Sea. Low-lying 

islands often are capped with limestone from ancient 

coral reefs, and other islands exhibit volcanic activity 

that has pushed up steep peaks that divert the moisture-laden northeasterly trade winds upward, greatly 

increasing rainfall.

Location of islands associated with the United States.

The U.S.-affiliated Pacific Islands include American 

Samoa, Guam, the State of Hawaii, the Republic of 

the Marshall Islands, the Federated States of Micronesia, the Commonwealth of the Northern Mariana 

Islands, and the Republic of Palau. These islands 

span a vast and diverse area from Hawaii, 3,900 mi 

west of the U.S. mainland, to Palau, about 566 mi 

east of the Philippines. Land masses vary widely and 

include small coral atolls; small sand islands; moderate-sized islands of mixed limestone and volcanic 

substrates; and large, high-elevation, volcanic islands.

The challenges of mainland forests—such as land use 

change, altered fire regimes, nonnative species invasions, insect and disease outbreaks, climate change, 

and other human-caused disturbances—become 

critical for societies with restricted, more immediately 

finite resource bases like those found on these islands.
54 U.S. Forest Resource Facts and Historical Trends

Land and forest area of the U.S. Caribbean and Pacific Islands.

Region and 

island group Land area Forest area

Forest 

cover

Acres (thousands) Percent

Caribbean

Puerto Rico 2,192 1,261 58

U.S. Virgin Islands 86 52 61

Pacific

American Samoa 48 44 90

Guam 136 64 47

Palau 112 97 87

CNMI 74 54 73

FSM 150 77 51

RMI 44 43 97

Hawaii 4,127 1,491 43

Total 6,968 3,182 67

CNMI = Commonwealth of the Northern Mariana Islands.

FSM = the Federated States of Micronesia. RMI = Republic 

of the Marshall Islands. 

The naturally high species diversity of tropical forests 

has been further augmented by human introduction of 

tree species from around the globe, some are beneficial and others are invasive.

0

2

4

6

8

10

12

14

16

Puerto

Rico

U.S. 

Virgin

Islands

American

Samoa

Guam Palau

Average tree species found

per sampled acre

Species diversity per sampled acre in the Caribbean 

and Pacific Islands.

The most important forestry concerns within the 

Islands involve losses of forest cover owing to urbanization, damages from invasive species, and the erosion of soils with subsequent siltation of coral reefs.
U.S. Forest Resource Facts and Historical Trends 55

Terms

forest land—Land at least 120 feet (ft) (37 meters 

[m]) wide and at least 1 acre (0.4 hectare) in size with 

at least 10-percent cover (or equivalent stocking) 

by live trees including land that formerly had such 

tree cover and that will be naturally or artificially 

regenerated. Trees are woody plants having a more 

or less erect perennial stem(s) capable of achieving at 

least 3 inches (in) (7.6 centimeters [cm]) in diameter 

at breast height, or 5 in (12.7 cm) diameter at root 

collar, and a height of 16.4 ft (5 m) at maturity in situ. 

Forest land does not include land that is predominantly under agricultural or urban land use.

growing stock volume—Live trees on timber land of 

commercial species meeting specified standards of 

quality and vigor. Cull trees are excluded from the 

volume. The volume includes only trees 5 in in diameter or larger at 4.5 ft above the ground.

growth (net annual)—The net volume increase of 

growing stock trees during a specified year. Components include the increment in net volume of trees at 

the beginning of the specific year surviving to its end, 

plus the net volume of trees reaching the minimum 

size class during the year, minus the volume of trees 

that died during the year, and minus the net volume 

of trees that became cull trees during the year.

hardwood—A dicotyledonous tree that is usually 

broad leaved and deciduous.

International Union for Conservation of Nature 

(IUCN) protection categories—The protected area 

categories are—

Category I is defined as (1) an area of land and/or 

sea that possesses some outstanding or representative ecosystems, possesses geological or physiological features and/or species, or is available primarily for scientific research and or environmental 

monitoring, or (2) a large area of unmodified or 

slightly modified land and/or sea, retaining its 
56 U.S. Forest Resource Facts and Historical Trends

natural character and influence, without permanent 

or significant habitation, that is protected and managed to preserve its natural condition.

Category II is a natural area of land and/or sea 

designated to (1) protect the ecological integrity 

of one or more ecosystems for present and future 

generations, (2) exclude exploitation or occupation 

critical to the purposes of designation of the area, 

and (3) provide a foundation for spiritual, educational, recreational, and visitor opportunities, all 

of which must be environmentally and culturally 

comparable.

Category III is an area of land and/or sea containing one or more specific natural or natural/cultural 

features that are of outstanding or unique value 

because of their inherent rarity, representative or 

aesthetic qualities, or cultural significance.

Category IV is an area of land and/or sea that is 

subject to active intervention for management purposes to ensure the maintenance of habitats and/or 

to meet the requirements of specific species.

Category V is an area of land with coast and sea, 

as appropriate, where the interaction of people and 

nature over time has produced an area of distinct 

character with significant aesthetic, ecological, 

and/or cultural value and often with high biological 

diversity. Safeguarding the integrity of this traditional interaction is vital to the protection, maintenance, and evolution of such an area.

Category VI is an area of land and/or sea containing predominantly unmodified natural systems, 

managed to ensure long-term protection and maintenance of biological diversity, while providing a 

sustainable flow of natural products and services to 

meet community needs.

logging residues—The unused portions of 

growing-stock trees that are cut or killed during 

logging and left in the woods.
U.S. Forest Resource Facts and Historical Trends 57

mortality—The volume of sound wood in growing 

stock trees that died from natural causes during a 

specified year.

national forest—An ownership class of Federal 

lands, designated by Executive order or statute as national forests or purchase units, and other lands under 

the administration of the Forest Service.

other Federal—An ownership class of Federal lands 

other than those administered by the Forest Service. 

Primarily lands owned by the Bureau of Land Management, National Park Service, U.S. Fish and Wildlife 

Service, and the Departments of Energy and Defense.

other forest land—Forest land other than timber land 

and reserved forest land. It includes available land 

that is incapable of producing annually at least 20 ft3

per acre (1.4 m3/hectare) of industrial wood under 

natural conditions because of adverse site conditions 

such as sterile soils, dry climate, poor drainage, high 

elevation, steepness, or rockiness.

removals—The net volume of growing stock trees removed from the inventory during a specified year by 

harvesting, cultural operations such as timber stand 

improvement, or land clearing.

reserved forest land—Forest land that is withdrawn 

from timber utilization through statute, administrative 

regulation, or designation. It does not include all land 

in International Union for Conservation of Nature 

protection categories.

roundwood products—Logs, bolts, and other round 

timber that are generated from harvesting trees for 

industrial or consumer use.

softwood—A coniferous tree, usually evergreen, that 

has needles or scale-like leaves.

timber land—Forest land that is capable of producing 

crops of industrial wood and not withdrawn from timber utilization by statute or administrative regulation. 
58 U.S. Forest Resource Facts and Historical Trends

(Note: Areas qualifying as timber land are capable 

of producing in excess of 20 ft3 per acre per year of 

industrial wood in natural stands.)

woodland—Land at least 120 ft (37 m) wide and at 

least 1 acre (0.4 hectares) in size with sparse trees 

capable of achieving 16.4 ft (5 m) in height with a 

tree canopy cover of less than 10 percent combined 

with shrubs at least 6 ft (2 m) in height to achieve an 

overall cover of more than 10 percent of woody vegetation. It does not include land that is predominantly 

under agricultural or urban land use.

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U.S. Forest Resource Facts and Historical Trends 61

Web Resources

USDA Forest Service

http://www.fs.fed.us

Forest Inventory and Analysis

http://fia.fs.fed.us

National Resource Assessment

http://www.fs.fed.us/research/rpa

Forest Health

http://www.fs.fed.us/foresthealth/

http://www.fs.fed.us/foresthealth/technology/nidrm.

shtml 

National Report on Sustainable Forests

http://www.fs.fed.us/research/sustain

Recreation/Wilderness

http://www.srs.fs.usda.gov/trends

http://www.fs.fed.us/recreationh

Forest Wildlife

http://www.fs.fed.us/research/rpa

Fire

http://www.nifc.gov/

http://www.firelab.org/project/wildland-fire-potential 

Forest Products

http://www.fia.fs.fed.us

http://www.fpl.fs.fed.us

Nontimber Forest Products

http://www.sfp.forprod.vt.edu

http://www.fao.org/forestry/site/6367/en

http://www.ntfpinfo.us/ 

Forest Ownership

http://www.fia.fs.fed.us/nwos/ 
62 U.S. Forest Resource Facts and Historical Trends

Protected Areas

http://www.IUCN.org

http://www.consbio.org

Water Resources

http://water.usgs.gov/watuse

http://www.fs.usda.gov/main/prc/issues#Water 

http://www.drought.unl.edu

Global Forest Information

http://www.fao.org/forestry/en/ 

http://www.fao.org/forestry/databases/en/ 

Urban Forests

http://www.itreetools.org

http://www.nrs.fs.fed.us/data/urban/ 
U.S. Forest Resource Facts and Historical Trends 63
http://fia.fs.fed.us

http://www.fs.fed.us/research/rpa

http://www.fs.fed.us/research/sustain