Changes in Land Use 

and Housing on Resource 

Lands in Washington State, 

1976–2006

Andrew N. Gray, David L. Azuma, Gary J. Lettman, 

Joel L. Thompson, and Neil McKay

United States 

Department of 

Agriculture

Forest Service

Pacific Northwest 

Research Station

General Technical Report 

PNW-GTR-881

March 2013

DEPAR TMENT OF AGRICULT URE
Authors

Andrew N. Gray is a research ecologist, Forestry Sciences Laboratory, 3200 

SW Jefferson Way, Corvallis, OR 97331; David L. Azuma is a research forester, 

Joel L. Thompson is a forestry technician, and Neil McKay is a research forester 

(retired), Forestry Sciences Laboratory, 620 SW Main St., Suite 400, Portland, 

OR 97208; Gary J. Lettman is a forest economist (retired), Forest Resource 

Planning, Oregon Department of Forestry, 2600 State Street, Salem, OR 97310.

Cover photograph: Agricultural area near Sequim, Washington, with recent 

urbanization and dispersed housing development in the nearby forest. Photo 

by Andrew Gray.

The Forest Service of the U.S. Department of Agriculture is dedicated to the principle of 

multiple use management of the Nation’s forest resources for sustained yields of wood, 

water, forage, wildlife, and recreation. Through forestry research, cooperation with the 

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a growing Nation.

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Abstract

Gray, Andrew N.; Azuma, David L.; Lettman, Gary J.; Thompson, Joel L.; 

McKay, Neil. 2013. Changes in land use and housing on resource lands in 

Washington state, 1976–2006. Gen. Tech. Rep. PNW-GTR-881. Portland, OR: 

U.S. Department of Agriculture, Forest Service, Pacific Northwest Research 

Station. 51 p.

Changes in human land use patterns have wide-ranging social, economic and 

ecological implications. How urban and residential areas develop to accommodate 

population increase can have varying effects on forest and agricultural production 

from resource lands. Estimates of the amount and type of land use change differ 

substantially with definitions and analytical methods used. The purpose of this 

study was to apply a robust manual image classification method to assess changes 

in land use and housing density across Washington state for a 30-year period. 

Digital imagery from 1976, 1994, and 2006 was classified to land use, classifications were assigned to a systematic-random grid of 44,554 photointerpretation 

points on nonfederal lands, and houses were identified within 80-ac circles around 

each nonurban point. Population in the state increased by 2.5 million people 

(66 percent) over the 30-year period, during which time 1.16 million acres were 

converted from forest and agriculture land use classes to residential and urban 

land uses. The greatest changes were in western Washington, where forest lands 

declined at a rate of 0.2 percent per year and intensive agricultural lands declined 

at a rate of 0.7 percent per year. Twenty percent of nonfederal land in western 

Washington was in developed land uses in 2006. The density of housing structures on lands that remained in forest and agricultural land uses also increased 

over the period of interest, particularly in areas close to developed land uses. 

The rate of housing increase on resource lands was greater from 1994 to 2006 

than from 1976 to 1994 in eastern Washington, but declined in western Washington. This method of assessing land use change compared favorably with other 

approaches, and had the advantage that it could be applied consistently to a longer 

period of time and allowed detailed assessment of patterns at local scales.

Keywords: Land use change, housing density, image classification, forestry, 

agriculture.
ii
1

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

Introduction

The amount and spatial pattern of human land use on the landscape have many 

social, economic, and ecological implications. These patterns change as the basis 

of local economies, regulation, and human population change. Common causes for 

these changes are peoples’ responses to economic opportunities, as mediated by 

institutional factors; for example, it may be a better investment to build houses than 

grow trees (Lambin et al. 2001). A common concern with current land use change 

in the United States is with the growth of housing and its effects on traditional 

economic production from rural lands (Kline et al. 2004, Wear et al. 1999) and on 

natural habitats and the ecosystem services they provide (Alig and Plantinga 2004, 

Brown et al. 2005, Radeloff et al. 2010). The obvious effect of land use conversion 

is magnified when rural or forested areas give way to urban uses, because the ecological function of the surrounding areas can also be affected (Gimmi et al. 2011). 

The area where such conversion is taking place is often called the wildland-urban 

interface (WUI). In Washington state, 66 percent of the net housing unit growth in 

the 1990s was in the WUI (Hammer et al. 2007).

In response to these concerns, some states in the Western United States have 

established planning efforts to develop land use plans, often at the county or 

multicounty level, to guide the location and nature of development. Consideration 

is usually given to preferred rural land uses, housing density in new developments, 

and dispersal of new residences in an area. In Washington, the Growth Management Act of 1990 required counties to adopt comprehensive plans and regulations 

to plan for and address the impacts of growth. The goals of county land use plans 

included conserving farm and forest land, reducing suburban sprawl, providing 

for open space and recreation, and sustaining natural-resource-based industries. 

In 2007, the state legislature prioritized the acquisition of valuable timberlands in 

danger of conversion to keep them in productive status.

Most of Washington’s population is found west of the crest of the Cascade 

Mountains. Monitoring of field plots by the U.S. Forest Service Forest Inventory 

and Analysis (FIA) program detected rapid conversion of forest land to nonforest land uses in western Washington in recent decades, with 5 percent of private 

timberland (270,000 ac) being converted between 1990 and 2000 (Gray et al. 2005), 

and a similar rate of loss in the previous decade (MacLean et al. 1992). These 

estimates are reliable because they are based on field measurements of a systematic 

sample of points on the landscape. However, with a density of sample points of one 

per 7,400 ac and a 10-year remeasurement period, the field plots do not allow for 

accurate estimates at spatial or temporal scales smaller than several counties over 
2

GENERAL TECHNICAL REPORT PNW-GTR-881

several years. The inventory plot measurements also do not provide information on 

housing density in rural areas and their changes over time.

An alternative approach assessed impacts of land use on management of 

forested plots in western Washington by delineating land use of surrounding areas 

on aerial photos (Oswald 1984). This approach was expanded by attributing the land 

use zone of thousands of photointerpretation points (roughly one point per 475 ac) at 

two points in time to describe changes in land use (MacLean and Bolsinger 1997). 

In recent years, this approach has been expanded, refined, and improved with the 

use of geographic information systems (GIS) and digital photography, allowing 

evaluation of changes over multiple time periods to assess the effectiveness of land 

use policy (Cathcart et al. 2007, Kline et al. 2004, Lettman et al. 2011).

It is important to distinguish land use from land cover. Areas in forest land use 

are periodically harvested (e.g., clearcut) and have little or no tree cover for several 

years. Alternatively, areas in urban or farm use may have substantial tree cover. 

Although land cover can be classified fairly well with coarse resolution satellite 

imagery (e.g., Homer et al. 2004, Powell et al. 2008), interpreting land use can be 

problematic. For example, distinguishing clearcuts from new developments and 

whether shrubby areas are young forests or brush fields can lead to errors in interpreting land use (e.g., Kline et al. 2009). Census estimates of population change 

have also been useful in assessing land use change, often in concert with analyses 

of satellite imagery (Northwest Environment Watch 2002, Radeloff et al. 2005), 

although they are often limited by the size of the census blocks and by image classification errors.

Fragmentation is an important attribute of forest area that has implications for 

the practicability and social acceptability of timber management, risk of homes to 

wildfire in the WUI, the spread of undesirable invasive plants and animals, and the 

quality and amount of habitat. One aspect of fragmentation and land use change 

that can be difficult to assess is the construction of dispersed home sites in forest land and other resource lands. Although the physical footprint of such houses 

can be relatively small and difficult to detect with satellite imagery, the social, 

economic, and environmental impact can be quite large. For example, residents 

may object to industrial forestry practices on adjoining lands, or domestic pets may 

harass or kill wildlife in surrounding lands.

The objectives of this study were to describe the amount and distribution of 

different land uses and housing structure densities in Washington and their changes 

from 1976 to 2006. We used the established methods reported in Lettman et al. 

(2011) and compared our results with estimates derived from other studies.
3

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

Methods

Study Area

The study area consisted of all 39 Washington counties, which are grouped in some 

analyses into five areas: Puget Sound, Olympic Peninsula, and southwest Washington west of the crest of the Cascade Mountains, and Central and Inland Empire 

east of the crest of the Cascade Mountains (fig. 1). Many other analyses summarize 

information by areas east and west of the Cascades. Elevations range from sea level 

to more than 14,000 ft, with most of the human population in the low elevations 

along the Puget Sound, Pacific coast, or lower Columbia Valley on the west side, 

and along the Columbia, Yakima, or Spokane River valleys on the east side. Most of 

the land area on the west side can support forest vegetation, except for high elevations with long-lasting winter snowpacks. On the east side, most forest vegetation is 

found in the higher elevations above the Columbia Plateau and major river valleys. 

A 12.2-million ac portion of the Columbia Basin was traditionally considered the 

“nonforest zone” in past FIA analyses, and consisted of most or all of Adams, 

Benton, Douglas, Franklin, Grant, Lincoln, Walla Walla, and Whitman Counties.

0 25 50 75 100

Kilometers

12.5

.

WHATCOM

SKAGIT

SNOHOMISH

Puget

Sound

KING

PIERCE

CLALLAM ISLAND

JEFFERSON

KITSAP

GRAYS MASON

HARBOR

THURSTON

ISLAND

Olympic KITSAP

Peninsula

PACIFIC LEWIS

Inland

Empire

OKANOGAN

FERRY STEVENS

LINCOLN SPOKANE

ADAMS WHITMAN

GARFIELD

COLUMBIA

WALLA WALLA

PEND

OREILLE

SKAMANIA

CHELAN

KITTITAS

YAKIMA

GRANT

FRANKLIN

BENTON

ASOTIN

CLARK

COWLITZ

Southwest

KLICKITAT

DOUGLAS

Central

WAHKIAKUM

Survey unit

Counties

Figure 1—Washington study area with the 39 counties identified and grouped into five regions for analysis.
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GENERAL TECHNICAL REPORT PNW-GTR-881

The lands in Washington are managed by a variety of owners and agencies. 

Although summaries of land use across all owners are provided, the analyses of 

land use change excluded lands managed by the U.S. Forest Service and National 

Park Service because their mandate was to maintain natural land cover, and any 

development (e.g., for ski areas or visitor facilities) was relatively small in area. 

Lands managed by these two agencies are referred to as “federal.” All other lands 

are referred to as “nonfederal,” although scattered areas amounting to 4.0 percent 

of the land area were managed by other federal agencies (81 percent of that was east 

side nonforest land). These other federal lands were included with state and local 

government lands in the “other public” owner group. The remaining nonfederal 

lands were managed by state and local government, forest industry, and other 

private owners, including Native American tribes. Although changes in ownership between national forest and other owner groups did occur during the period 

of interest, they were small compared to the changes in land use (Gray et al. 2005, 

2006). For simplicity, land ownership as determined for the 1990 forest inventories 

of eastern and western Washington (MacLean et al. 1992, McKay et al. 1995) was 

used for all analyses. For these inventories, private landowners were classified as 

being either forest industry (i.e., with large landholdings and intensive management) 

or “other private” (which included lands managed by Native American tribes).

Land Classification 

The land use classes used for this study were the same categories used for the 

studies of land use change in Oregon (Lettman et al. 2011). Land use classes were 

defined by a combination of land cover, density and spatial pattern of human structures, road density, and the amount of area in contrasting, contiguous land uses. 

Small areas of apparently different land use could be included in an overall land use 

polygon. The term “structure” is meant to represent individual dwellings, thus multiple associated buildings were counted only once. For example, an adjoining rural 

house, barn, shed, and pumphouse would all count as a single structure. Examples 

of land use types are shown in figures 2 and 3. Land use class definitions were:

Wildland forest: Polygon ≥ 1 mi2

 (640 ac); structures (if any) were scattered 

across the area; >80 percent of the area was forest land and included managed 

and unmanaged lands.

Wildland range: Polygon ≥ 1 mi2

; structures (if any) were scattered across the 

area; <51 percent of the area was forest land; <20 percent was agricultural land, 

and the remainder was nondeveloped rangeland and included managed and 

unmanaged lands.
5

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

Mixed forest/agriculture: Polygon ≥ 1 mi2; structures were scattered across the 

area; 20 to 80 percent of the area was agricultural; and forest land was ≥50 percent 

of the remainder. Improved roads were typically 1⁄2 mile apart or more.

Mixed range/agriculture: Polygon ≥ 1 mi2

; structures were scattered across the 

area; 20 to 80 percent of the area was agricultural; and rangeland was ≥50 percent 

of the remainder. Improved roads were typically 1⁄2 mi apart or more.

Intensive agriculture: Polygon ≥1 mi2

; structures were scattered across the area; 

>80 percent of the area was agricultural.

Low-density residential/commercial: Polygon of any size, but must have had 

at least nine structures within it. Housing developments were generally less than 

80 ac. Improved roads were typically 1⁄4 mi apart or less. House lots were usually 

>1 ac. The polygon could have also met urban qualifications but was <40 ac.

Urban: Polygon ≥40 ac, consisting of commercial, service, or residential subdivided area with city road patterns and closely spaced buildings. House lots 

were usually <1 ac.

Other: Polygon ≥ 640 ac, consisting of lava, sand, reservoirs, lakes, and 

mountaintop rock, snow, and ice.

Figure 2—Example of land use class classification on aerial photography of western Washington, illustrating the differences in 

housing density, road patterns, and land cover patterns used to delineate class boundaries.

Urban 

Mixed forest/agriculture 

Residential 

Intensive 

agriculture 

Wildland 

forest 
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GENERAL TECHNICAL REPORT PNW-GTR-881

In some analyses, the wildland forest, wildland range, mixed forest/agriculture, mixed range/agriculture, and intensive agriculture classes were identified as 

“resource lands” and low-density residential/commercial and urban classes were 

identified as “developed areas.” Although structure density was included as a 

criterion in the land use definitions for resource land classes, the apparent land use 

was the overriding factor. There were many cases in western Washington where 

structure densities were greater than eight structures per square mile, but the land 

cover indicated resource use, and the road density and scattered housing did not 

meet the low-density residential definition.

Golf courses, industrial parks, airports, maintained parks, mills or other industrial complexes, quarries, and dams adjacent to or within 1⁄4 mile of an urban class 

were included in the urban class. However, if these uses were not within 1⁄4 mile of 

an urban class and were ≥40 ac, they were classified as low-density residential; if 

<40 ac, they were not distinguished from the surrounding area.

Figure 3—Example of land use class classification on aerial photography of eastern Washington, illustrating the differences in housing 

density, road patterns, and land cover patterns used to delineate class boundaries.

Intensive 

agriculture 

Wildland 

forest 

Residential 

Wildland 

range 
7

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

Imagery and Image Interpretation

The imagery used for this study was based on aerial photography, which was either 

captured digitally or digitized and georeferenced afterward. The imagery for the 

first time period was based on Washington Department of Natural Resources aerial 

photographs from three different projects. The Olympic Peninsula and northwest 

Washington photos were natural color at a scale of 1:24,000. In southwest Washington, black and white photos at a scale of 1:40,000 were used. Photos for this time 

period were not available for the “nonforest zone” in eastern Washington. Almost 

all of the west side photos were taken in 1976, while the east side photos ranged 

from 1970 for the southeast corner of the state to 1978 with an overall east side 

mean of 1976. The photos were digitally scanned at a resolution of 1,200 pixels/

in2

 and georegistered in a geographic information system (GIS) using recognizable 

points and existing registered imagery from later dates. The imagery for the second 

time period consisted of 1-m-resolution black and white imagery from the National 

Digital Ortho Program and acquired from the U.S. Department of Agriculture 

(USDA) Farm Service Agency, Aerial Photography Field Office (Salt Lake City, 

Utah). Most images dated from the early 1990s, but ranged from 1989 to 2001, with 

average dates by county ranging from 1990 to 1995 (except 1996 for Yakima, 1997 

for Pend Oreille, and 1998 for Wahkiakum Counties), with an overall mean date of 

1993.8 (nominal year of 1994 was used for results). The imagery for the last time 

period consisted of 1-m-resolution color digital imagery for the entire state from the 

National Agricultural Imagery Program taken in 2006, and also acquired from the 

Farm Service Agency.

Land use class polygons were delineated in GIS over displayed imagery for 

different dates. Multiple interpreters worked on the project and checked each other’s 

work. In addition, interpreters worked on different counties for different time periods, providing another check as areas were assessed through time. Land use calls 

were assigned to a systematic-random grid of 44,554 photointerpretation points on 

nonfederal lands, with a density of one point per 462 ac, except for the 12.2 million 

acre eastern Washington “nonforest zone,” where the grid density was one point per 

6,000 ac. Points were used to assess change in classes over time, calculate distances 

to different contrasting land uses, and count structures. 

Structures were counted in 80-ac circles around each nonurban grid point, in 

effect sampling 17 percent of the nonurban classes. However, structures in urban 

classes were counted when point centers were in a different class, and conversely 

structures in nonurban classes were not counted if the grid point was urban. Structures were individually identified in GIS, which simplified and reduced errors in 

assessing changes in structures over time. Structures could also be identified with 
8

GENERAL TECHNICAL REPORT PNW-GTR-881

the land use polygon they fell in, as well as with the land use status of the grid 

point. Analyses of these two approaches are distinguished by referring to density of 

structures in the 80 ac “around” points in land use classes vs. density of structures 

“in” different land use classes.

For points in urban land use at any time period, tree cover was estimated from 

imagery for a 2.5-ac circle surrounding each point. As a calibration method, crown 

outlines were delineated in GIS on a portion of high-resolution digital images, and 

area calculated to estimate cover. Cover was estimated visually on the remainder of 

the points.

We compared our land use classifications with the national land cover classification created from satellite imagery referred to as the National Land Cover 

Database (NLCD) (Homer et al. 2004). Points were intersected with the 30 m pixels 

in the NLCD 2001 database for Washington. Land cover categories and estimated 

tree cover values from NLCD were associated with each point and summarized by 

our land use classes.

Statistical Analyses

Most analyses were based on the land use classification of individual grid points 

and their changes over time, with each point assigned an area weight based on the 

number of grid points on nonfederal land in each county. Estimates for nonfederal 

land area were based on U.S. Census Bureau area figures and federal land ownership figures maintained by each agency. For grid points in the eastern Washington 

nonforest zone where imagery for 1976 was not available, the land use for the first 

time period was assumed to be the same as for the second time period (i.e., no 

change). Standard errors for estimates of area in different zones were calculated 

as in Lund and Thomas (1989), using standard equations for proportions of sample 

points in different classes. Structure density calculations used the grid point area 

weights (i.e., acres per point) as weights to account for the lower density of points in 

the nonforest zone. Calculations of rates of change were based on the mean decimal years between dates for the grid points in each cell being analyzed. All rates 

presented are the compound annual rates of change.

Results

Between 1970 and 2006, human population almost doubled (a 93 percent increase) 

in western Washington and increased by 66 percent in eastern Washington (USDC 

CB 2008; table 1). To match the image dates, interpolation between census figures 

resulted in an estimated statewide population of 3.84 million in 1976 and 5.3 

million in 1994, with a 66-percent increase between 1976 and 2006. The largest 

increases in population occurred in the already populous counties in the Puget 

Washington’s 

population increased 

by 66 percent from 

1976 to 2006.
9

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

Table 1—Human population in Washington by census year and county, and overall percentage of change

Population Change from

Area County 1970 1980 1990 2000 2006 1970 to 2006

- - - - - - - - - - - - - - - - - - - - - - Number - - - - - - - - - - - - - - - - - - - - - - Percent

Western Washington:

Puget Sound Island 27,011 44,048 60,195 71,558 80,857 53,846 199.3

Puget Sound King 1,159,369 1,269,898 1,507,319 1,737,034 1,834,194 674,825 58.2

Puget Sound Kitsap 101,732 147,152 189,731 231,969 238,827 137,095 134.8

Puget Sound Pierce 412,344 485,667 586,203 700,820 763,670 351,326 85.2

Puget Sound San Juan 3,856 7,838 10,035 14,077 15,144 11,288 292.7

Puget Sound Skagit 52,381 64,138 79,555 102,979 114,495 62,114 118.6

Puget Sound Snohomish 265,236 337,720 465,642 606,024 664,581 399,345 150.6

Puget Sound Whatcom 81,983 106,701 127,780 166,814 188,775 106,792 130.3

Olympic Peninsula Clallam 34,770 51,648 56,464 64,525 69,716 34,946 100.5

Olympic Peninsula Grays Harbor 59,553 66,314 64,175 67,194 70,836 11,283 18.9

Olympic Peninsula Jefferson 10,661 15,965 20,146 25,953 29,029 18,368 172.3

Olympic Peninsula Mason 20,918 31,184 38,341 49,405 54,915 33,997 162.5

Olympic Peninsula Thurston 76,894 124,264 161,238 207,355 233,167 156,273 203.2

Southwest Clark 128,454 192,227 238,053 345,238 409,230 280,776 218.6

Southwest Cowlitz 68,616 79,548 82,119 92,948 98,831 30,215 44.0

Southwest Lewis 45,467 56,025 59,358 68,600 72,759 27,292 60.0

Southwest Pacific 15,796 17,237 18,882 20,984 21,401 5,605 35.5

Southwest Skamania 5,845 7,919 8,289 9,872 10,524 4,679 80.1

Southwest Wahkiakum 3,592 3,832 3,327 3,824 3,949 357 9.9

 Total 2,574,478 3,109,325 3,776,852 4,587,173 4,974,900 2,400,422 93.2

Eastern Washington:

Central Chelan 41,103 45,061 52,250 66,616 70,023 28,920 70.4

Central Douglas 16,787 22,144 26,205 32,603 35,266 18,479 110.1

Central Kittitas 25,039 24,877 26,725 33,362 37,981 12,942 51.7

Central Klickitat 12,138 15,822 16,616 19,161 19,815 7,677 63.2

Central Okanogan 25,867 30,663 33,350 39,564 39,231 13,364 51.7

Central Yakima 145,212 172,508 188,823 222,581 230,840 85,628 59.0

Inland Empire Adams 12,014 13,267 13,603 16,428 16,614 4,600 38.3

Inland Empire Asotin 13,799 16,823 17,605 20,551 21,049 7,250 52.5

Inland Empire Benton 67,540 109,444 112,560 142,475 157,549 90,009 133.3

Inland Empire Columbia 4,439 4,057 4,024 4,064 3,964 -475 -10.7

Inland Empire Ferry 3,655 5,811 6,295 7,260 7,495 3,840 105.1

Inland Empire Franklin 25,816 35,025 37,473 49,347 66,138 40,322 156.2

Inland Empire Garfield 2,911 2,468 2,248 2,397 2,118 -793 -27.2

Inland Empire Grant 41,881 48,522 54,758 74,698 81,348 39,467 94.2

Inland Eempire Lincoln 9,572 9,604 8,864 10,184 10,217 645 6.7

Inland Empire Pend Oreille 6,025 8,580 8,915 11,732 12,664 6,639 110.2

Inland Empire Spokane 287,487 341,835 361,364 417,939 447,392 159,905 55.6

Inland Empire Stevens 17,405 28,979 30,948 40,066 41,293 23,888 137.2

Inland Empire Walla Walla 42,176 47,435 48,439 55,180 57,609 15,433 36.6

Inland Empire Whitman 37,900 40,103 38,775 40,740 41,404 3,504 9.2

 Total 838,766 1,023,028 1,089,840 1,306,948 1,400,010 561,244 66.9

Washington total 3,413,244 4,132,353 4,866,692 5,894,121 6,374,910 2,961,666 86.8

Source: U.S. Department of Commerce, Census Bureau (2008); 2006 figures estimated.
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GENERAL TECHNICAL REPORT PNW-GTR-881

Sound area (King, Pierce, and Snohomish Counties), although increases of more 

than 150,000 people also occurred in Thurston, Clark, and Spokane Counties. The 

average annual increase in population over the period was 80,000, with the greatest 

increases occurring between 1990 and 2000 with an average increase of 103,000 

people per year.

The land area of Washington was 42.6 million ac, of which 11.0 million ac (26 

percent) were managed as national forests or national parks, referred to as “federal 

land” (table 2). The majority of the federal land (93 percent west side, 98 percent 

east side) was in the wildland forest land use class, with the remainder consisting 

of bare rock, sand, and ice in the “other” class. Because land use did not change 

on federal land, these areas were not included in subsequent analyses. Of the 24.2 

million ac of wildland forest class in 1976, 56 percent (13.7 million ac) was in 

nonfederal ownership (illustrated in figure 4).

Table 2—Area of land use in Washington in 1976 by side of state and federal or nonfederal status

Eastern Washington Western Washington

Land-use class Federal Nonfederal Federal Nonfederal Total

Thousand Thousand Thousand Thousand Thousand acres Percent acres Percent acres Percent acres Percent acres Percent

Wildland forest 5,444 22 5,904 24 5,082 21 7,809 32 24,239 100

Wildland range 22 0 6,081 100 6,102 100

Mixed forest/agriculture 0 0 182 33 1 0 365 67 548 100

Mixed range/agriculture 1 1 64 99 65 100

Intensive agriculture 1 0 8,174 91 851 9 9,026 100

Low-density residential 2 0 389 30 1 0 913 70 1,305 100

Urban 226 37 386 63 612 100

Other 59 8 216 30 400 56 39 5 715 100

 Total 5,531 13 21,238 50 5,483 13 10,363 24 42,614 100

Note: percentages are of state totals for each row.

In western Washington, the area in the nonfederal wildland forest land use 

class was 7.81 million ac in 1976 and declined by 493,000 ac (6.3 percent) between 

1976 and 2006 (table 3), for an annual rate of decline of 0.22 percent per year. This 

rate is equivalent to losing an area of forest land use the size of a 1.32-ac football 

field every 42 minutes for the last 30 years. Although smaller declines in area were 

observed for the mixed forest/agriculture and intensive agriculture classes, the 

proportional declines were substantially greater, with annual rates of 1.0 and 0.7 

percent per year, respectively (table 4). In eastern Washington, declines of nonfederal wildland forest were lower in magnitude and rate than in western Washington, 

with an overall loss of 157,000 ac at an annual rate of 0.09 percent per year. Overall 

declines in wildland range in eastern Washington were comparable to those of 

Washington lost 

650,000 acres of 

forest land use from 

1976 to 2006.
11

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006 Figure 4—Delineated land use classes in Washington in 2006, and federal lands. .0 25 50 75 100 Kilometers 12.5 Intensive agriculture Mixed forest/agriculture Mixed range/agriculture Low-density residential Urban Federal land Wildland forest Wildland range Other (sand, rock, lava, water)
12

GENERAL TECHNICAL REPORT PNW-GTR-881

Table 3—Area of nonfederal land in Washington and percentages of total by side 

of state, land use class, and year

Land use class 1976 1994 2006

Thousand Thousand Thousand

acres Percent acres Percent acres Percent

Eastern Washington:

Wildland forest 5,904 27.8 5,798 27.3 5,748 27.1

Wildland range 6,081 28.6 6,035 28.4 5,945 28.0

Mixed forest/agriculture 182 0.9 165 0.8 157 0.7

Mixed range/agriculture 64 0.3 64 0.3 64 0.3

Intensive agriculture 8,174 38.5 8,111 38.2 8,086 38.1

Low-density residential 389 1.8 589 2.8 723 3.4

Urban 226 1.1 259 1.2 299 1.4

Other 216 1.0 216 1.0 216 1.0

 Total 21,238 100.0 21,238 100.0 21,238 100.0

Western Washington:

Wildland forest 7,809 75.4 7,501 72.4 7,316 70.6

Mixed forest/agriculture 365 3.5 310 3.0 269 2.6

Intensive agriculture 851 8.2 748 7.2 683 6.6

Low-density residential 913 8.8 1,245 12.0 1,414 13.6

Urban 386 3.7 517 5.0 636 6.1

Other 39 0.4 43 0.4 45 0.4

 Total 10,363 100.0 10,363 100.0 10,363 100.0

Table 4—Changes in area of nonfederal land in Washington and annual rates of 

change by side of state, land-use class, and period

Land use class 1976–1994 1994–2006 1976–2006

Thousand Thousand Thousand

acres Percent acres Percent acres Percent

Eastern Washington:

Wildland forest -106.3 -0.10 -50.3 -0.08 -156.6 -0.09

Wildland range -46.0 -0.04 -89.8 -0.14 -135.7 -0.07

Mixed forest/agriculture -17.2 -0.56 -7.9 -0.42 -25.1 -0.51

Mixed range/agriculture 0 0 0 0 0 0

Intensive agriculture -63.5 -0.04 -24.6 -0.03 -88.1 -0.04

Low-density residential 200.1 2.32 133.2 1.92 333.3 2.17

Urban 32.8 0.77 39.5 1.28 72.3 0.96

Other 0 0 0 0 0 0

Western Washington:

Wildland forest -308.6 -0.24 -184.5 -0.18 -493.1 -0.22

Mixed forest/agriculture -55.0 -0.99 -41.6 -1.05 -96.7 -1.02

Intensive agriculture -102.9 -0.74 -64.4 -0.71 -167.3 -0.73

Low-density residential 332.1 1.97 169.9 0.91 502.0 1.47

Urban 130.7 1.87 118.9 1.46 249.6 1.68

Other 3.7 0.56 1.9 0.30 5.6 0.44
13

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

forest land, and declines in agriculture zones were lower in magnitude and rate 

(some calculated rates of change do not appear to align well with net change in 

acres for different time periods because the actual date of the midpoint varied from 

1994). County-level changes are shown in the appendix.

Developed land classes covered 12.5 percent of nonfederal land in western 

Washington in 1976 and increased to 19.7 percent by 2006, representing annual 

rates of increase in area of 1.5 and 1.7 percent for low-density residential and urban 

classes, respectively. In eastern Washington, developed classes only covered 2.9 

percent of nonfederal land in 1976, but increased to 4.8 percent by 2006, with 

annual rates of increase of 2.2 and 1.0 percent for low density and urban, respectively. The largest changes from resource lands (wildland forest or range, mixed 

forest/agriculture or mixed range/agriculture, and intensive agriculture classes) 

to developed lands occurred in the Puget Sound area (table 5). Most of the land 

surrounding the shores of Puget Sound was in the developed land classes in 2006. 

The increase in development between 1976 and 2006 exhibited a dispersed pattern 

in the lowlands of western Washington, and in Spokane and Stevens Counties in 

eastern Washington (fig. 5). The pattern of change from 1976 to 1994 was more 

evenly dispersed than development between 1994 and 2006 (fig. 6).

Although 51 percent of the wildland forest class in western Washington in 

1976 was owned by forest industry, and 25 percent by other private owners, most 

of the loss of wildland forest (88 percent) occurred on other private land (table 6). 

In eastern Washington, a higher percentage of the wildland forest class was owned 

by other private (62 percent), where most of the loss of wildland forest occurred (91 

percent).

In western Washington, most of the land that changed to low-density residential between 1976 and 2006 was from wildland forest, although the proportional 

changes from mixed-forest agriculture and intensive agriculture were much higher 

(tables 7 and 8). The proportional contribution from wildland forest to low-density 

residential was similar between periods: 67 percent for 1976 to 1994 and 63 percent for 1994 to 2006. Most of the urban area came from low-density residential 

although a substantial portion of the new urban area (24 percent) was forested in 

1976 (fig. 7). 

Twenty percent of 

nonfederal land was 

in developed land use 

by 2006.
14

GENERAL TECHNICAL REPORT PNW-GTR-881

Table 5—Area of different land use classes on nonfederal land in different regions of 

Washington and percentages of total by area, land-use class, and year

Land use class 1976 1994 2006

Thousand Thousand Thousand

acres Percent acres Percent acres Percent

Puget Sound:

Wildland forest 2,517 61.5 2,306 56.3 2,207 53.9

Mixed forest/agriculture 167 4.1 129 3.1 110 2.7

Intensive agriculture 480 11.7 409 10.0 384 9.4

Low-density residential 605 14.8 822 20.1 891 21.8

Urban 307 7.5 411 10.0 484 11.8

Other 16 0.4 16 0.4 16 0.4

 Total 4,092 100.0 4,092 100.0 4,092 100.0

Olympic Peninsula:

Wildland forest 2,660 86.6 2,601 84.6 2,555 83.1

Mixed forest/agriculture 71 2.3 64 2.1 55 1.8

Intensive agriculture 140 4.5 122 4.0 104 3.4

Low-density residential 157 5.1 229 7.4 282 9.2

Urban 29 1.0 42 1.4 62 2.0

Other 15 0.5 15 0.5 15 0.5

 Total 3,073 100.0 3,073 100.0 3,073 100.0

Southwest Washington:

Wildland forest 2,631 82.3 2,594 81.1 2,554 79.9

Mixed forest/agriculture 127 4.0 118 3.7 103 3.2

Intensive agriculture 231 7.2 216 6.8 195 6.1

Low-density residential 150 4.7 194 6.1 241 7.5

Urban 50 1.6 64 2.0 90 2.8

Other 8 0.3 12 0.4 14 0.4

 Total 3,198 100.0 3,198 100.0 3,198 100.0

Central Washington:

Wildland forest 2,964 37.8 2,931 37.3 2,913 37.1

Wildland range 2,934 37.4 2,888 36.8 2,862 36.5

Mixed forest/agriculture 21 0.3 17 0.2 16 0.2

Mixed range/agriculture 54 0.7 54 0.7 54 0.7

Intensive agriculture 1,687 21.5 1,666 21.2 1,640 20.9

Low-density residential 106 1.4 199 2.5 263 3.4

Urban 52 0.7 62 0.8 69 0.9

Other 33 0.4 33 0.4 33 0.4

 Total 7,850 100.0 7,850 100.0 7,850 100.0

Inland Empire:

Wildland forest 2,941 22.0 2,867 21.4 2,834 21.2

Wildland range 3,147 23.5 3,147 23.5 3,083 23.0

Mixed forest/agriculture 161 1.2 148 1.1 141 1.1

Mixed range/agriculture 10 0.1 10 0.1 10 0.1

Intensive agriculture 6,487 48.5 6,445 48.1 6,446 48.1

Low-density residential 283 2.1 390 2.9 459 3.4

Urban 175 1.3 197 1.5 230 1.7

Other 184 1.4 184 1.4 184 1.4

 Total 13,388 100.0 13,388 100.0 13,388 100.0
15

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

.0 25 50 75 100

Kilometers

12.5

Change to agriculture

Decrease in development

Increase in development 

Figure 5—Change in development in Washington between 1976 and 2006. Change from forest land, range, agriculture, mixed 

forest/agriculture or mixed range/agriculture to low-density residential or urban was classified as an increase in development; 

change from any land use to agriculture was classified separately, and any other change from low-density or urban to other types 

was classified as a decrease in development.

Table 6—Changes in the area of wildland forest land use class in Washington by side of state, owner 

class, and year

Area Change from 1976 to 2006

Owner class 1976 1994 2006 Area Annual rate Percentage of total

- - - - - - - - - - - - Thousand acres - - - - - - - - - - - - - - - - Percent - - - - - -

Eastern Washington:

 Forest industry 1,095.1 1,091.8 1,089.4 -5.7 -0.02 3.6

 Other private 3,640.2 3,543.3 3,497.2 -143.0 -0.14 91.3

 State and local 1,006.4 1,001.3 1,000.8 -5.6 -0.02 3.6

 Other federal 162.5 161.5 160.1 -2.3 -0.05 1.5

 Total 5,904.2 5,797.9 5,747.6 -156.6 -0.09 100.0

Western Washington:

 Forest industry 4,026.7 4,011.0 3,984.3 -42.4 -0.04 8.6

 Other private 1,910.8 1,629.3 1,479.3 -431.6 -0.85 87.5

 State and local 1,756.9 1,746.9 1,740.0 -16.9 -0.03 3.4

 Other federal 114.7 113.3 112.4 -2.3 -0.07 0.5

 Total 7,809.1 7,500.5 7,316.0 -493.1 -0.22 100.0
16

GENERAL TECHNICAL REPORT PNW-GTR-881

1976–1994 1994–2006

. 0 25 50 75 100

Kilometers

12.5

Change to agriculture

Decrease in development

Increase in development 

Figure 6—Change in development in western Washington between 1976 to 1994 and 1994 to 2006. Change from forest land, range, 

agriculture, mixed forest/agriculture or mixed range/agriculture to low-density residential or urban was classified as an increase in 

development; change from any land use to agriculture was classified separately, and any other change from low-density or urban to 

other types was classified as a decrease in development.
17

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

Table 7—Net change in area between land use classes on nonfederal land in western Washington, 

1976–1994 and 1994–2006

Wildland Mixed forest/ Intensive Low-density

Description of change forest agriculture agriculture residential Urban Other

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - Acres - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Area by class in 1976 7,809,084 365,225 850,613 912,506 386,091 39,272

Net change from:

Wildland forest 0 2,332 -1,456 279,944 24,047 3,690

Mixed forest/agriculture -2,332 0 -932 53,716 4,572

Intensive agriculture 1,456 932 0 80,190 20,311

Low-density residential -279,944 -53,716 -80,190 0 81,747

Urban -24,047 -4,572 -20,311 -81,747 0

Other -3,690 0

 Total net change -308,557 -55,025 -102,889 332,103 130,677 3,690

Area by class in 1994 7,500,527 310,201 747,724 1,244,609 516,768 42,962

Net change from:

Wildland forest 0 5,066 3,217 152,176 22,694 1,384

Mixed forest/agriculture -5,066 0 -917 39,862 7,767

Intensive agriculture -3,217 917 0 48,352 18,372

Low-density residential -152,176 -39,862 -48,352 0 70,043 482

Urban -22,694 -7,767 -18,372 -70,043 0

Other -1,384 -482 0

 Total net change -184,537 -41,645 -64,424 169,864 118,877 1,866

Area by class in 2006 7,315,990 268,556 683,300 1,414,473 635,644 44,828

Table 8—Net change in area between land use classes on nonfederal land in western Washington, 

1976–2006

Wildland Mixed forest/ Intensive Low-density

Description of change forest agriculture agriculture residential Urban Other

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - Acres - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Area by class in 1976 7,809,084 365,225 850,613 912,506 386,091 39,272

Net change from:

Wildland forest 0 6,935 1,761 419,678 59,646 5,074

Mixed forest/agriculture -6,935 0 -917 91,718 12,803

Intensive agriculture -1,761 917 0 122,126 46,030

Low-density residential -419,678 -91,718 -122,126 0 131,074 482

Urban -59,646 -12,803 -46,030 -131,074 0

Other -5,074 -482 0

 Total net change -493,094 -96,670 -167,313 501,967 249,554 5,556

Area by class in 2006 7,315,990 268,556 683,300 1,414,473 635,644 44,828
18

GENERAL TECHNICAL REPORT PNW-GTR-881

In eastern Washington, the greatest change in area to low-density residential 

was from intensive agriculture, although the rate of conversion from wildland forest 

was similar (tables 9 and 10). The proportional contribution from wildland forest to 

low-density residential declined somewhat between periods: 41 percent for 1976 to 

1994 and 32 percent for 1994 to 2006. Development of wildland range and mixedagriculture classes was substantially lower than of forest or intensive agriculture 

classes. The increase in urban area in eastern Washington was substantially lower 

than in western Washington, but most of the new urban area (63 percent) was in 

resource land uses in 1976 (fig. 8).

Most of the land that changed from resource use to urban or low-density residential was in areas close to existing urban or residential classes, with the majority 

being less than 1⁄4 mi away (figs. 9 and 10). A greater proportion of the development 

in western Washington occurred close to previously developed lands than in eastern 

Washington. For both sides of the state, however, more of the development was 

close to previous development from 1994 to 2006 than for 1976 to 1994. Most of the 

resource use areas that became closer to development in the study period were not 

near the major metropolitan areas, but were scattered around the region, suggesting 

that potential effects of development on resource use are widespread (fig. 11).

Figure 7—Western Washington net change in area from resource classes (forest land, mixed forest/

agriculture, or intensive agriculture) to developed classes (low-density residential or urban) from 

1976 to 2006.

0

50

100

150

200

250

300

350

400

450

Land use class

Change between 1976 and 2006 (thousand acres)

To low-density residential

To urban

From wildland forest From mixed 

forest/agriculture

From intensive

agriculture

Most new development 

was within 1⁄4 mile of 

existing development.
19

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

Table 9—Net change in area between land use classes on nonfederal land in eastern Washington, 1976–1994 

and 1994–2006

Wildland Wildland Mixed forest/ Mixed range/ Intensive Low-density 

Description of change forest range agriculture agriculture agriculture residential Urban

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Acres - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Area by class in 1976 5,904,215 6,080,759 181,767 64,482 8,174,433 389,296 226,295

Net change from:

Wildland forest 0 1,384 461 1,403 86,460 16,609

Wildland range -1,384 0 922 28,147 18,285

Mixed forest/agriculture -461 0 16,743 927

Mixed range/agriculture -922 0 940

Intensive agriculture -1,403 -28,147 0 90,205 2,794

Low-density residential -86,460 -18,285 -16,743 -940 -90,205 0 12,508

Urban -16,609 -927 -2,794 -12,508 0

 Total net change -106,316 -45,970 -17,209 -17 -63,450 200,125 32,838

Area by class in 1994 5,797,900 6,034,788 164,558 64,464 8,110,983 589,421 259,133

Net change from:

Wildland forest 0 -510 48,950 1,869

Wildland range 0 49,729 28,177 11,867

Mixed forest/agriculture 0 7,425 464

Mixed range/agriculture 0

Intensive agriculture 510 -49,729 0 66,251 7,605

Low-density residential -48,950 -28,177 -7,425 -66,251 0 17,648

Urban -1,869 -11,867 -464 -7,605 -17,648 0

 Total net change -50,309 -89,773 -7,888 0 -24,637 133,155 39,452

Area by class in 2006 5,747,590 5,945,015 156,670 64,464 8,086,346 722,576 298,585

Note: The “other” land use class had no change and is not shown.

Table 10—Net change in area between land use classes on nonfederal land in eastern Washington, 1976–2006

Wildland Wildland Mixed forest/ Mixed range/ Intensive Low-density 

Description of change forest range agriculture agriculture agriculture residential Urban

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Acres - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Area by class in 1976 5,904,215 6,080,759 181,767 64,482 8,174,433 389,296 226,295

Net change from:

Wildland forest 0 1,384 461 431 134,944 19,405

Wildland range -1,384 0 922 77,876 46,462 11,867

Mixed forest/agriculture -461 0 23,705 1,854

Mixed range/agriculture -922 0 940

Intensive agriculture -431 -77,876 0 154,146 12,249

Low-density residential -134,944 -46,462 -23,705 -940 -154,146 0 26,916

Urban -19,405 -11,867 -1,854 -12,249 -26,916 0

 Total net change -156,625 -135,743 -25,097 -17 -88,087 333,280 72,290

Area by class in 2006 5,747,590 5,945,015 156,670 64,464 8,086,346 722,576 298,585

Note: The “other” land use class had no change and is not shown.
20

GENERAL TECHNICAL REPORT PNW-GTR-881

Figure 8—Eastern Washington net change in area from resource classes (forest land, range, mixed forest/agriculture or 

mixed range/agriculture, intensive agriculture) to developed classes (low-density residential or urban) from 1976 to 2006.

Figure 9—Western 

Washington net change 

in area from resource 

classes (forest land, agriculture, or mixed forest/

agriculture) to developed 

classes (low-density 

residential or urban) for 

two periods (1976–1994 

and 1994–2006) by 

initial distance to 

developed classes.

0

20

40

60

80

100

120

140

160

180

To low-density residential

To urban

Change between 1976 and 2006 (thousand acres)

Land use class

From 

wildland forest

From 

wildland range

From intensive

agriculture

From mixed 

forest/agriculture

From mixed 

range/agriculture

0

2,000

4,000

6,000

8,000

10,000

12,000

14,000

16,000

18,000

20,000

Annual rate of change (acres)

1976–1994

1994–2006

<1/4 mi 1/4 to 1/2 mi 1/2 to 1 mi >1 mi

Distance to urban or low-density residential land use zone
21

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

Figure 10—Eastern Washington net change in area from resource classes (forest land, agriculture, 

or mixed forest/agriculture) to developed classes (low-density residential or urban) for two periods 

(1976–1994 and 1994–2006) by initial distance to developed classes.

10,000

9,000

8,000

7,000

6,000

5,000

4,000

3,000

2,000

1,000

0

Annual rate of change (acres)

1976–1994

1994–2006

<1/4 mi 1/4 to 1/2 mi 1/2 to 1 mi >1 mi

Distance to urban or low-density residential land use zone
22

GENERAL TECHNICAL REPORT PNW-GTR-881

.

0 25 50 75 100 12.5

Kilometers

Changed to <1 miRemained <1 miRemained >1 mi

Figure 11—Map of change in distance from resource classes (forest land, agriculture, or mixed forest/agriculture) to the nearest developed classes (low-density residential or urban) from 1976 to 2006.
23

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

Across the state, the median elevation and slope for the forest and residential 

classes increased over time, while they decreased or remained stable for intensive 

agriculture. These results indicate that, on balance, development was moving into 

higher elevation, steeper forested areas instead of lower elevation agricultural areas 

(table 11). The lower elevation areas may also be more prone to flooding, which may 

be a factor affecting development patterns.

The mean density of structures counted in 80-ac circles around each western 

Washington photointerpretation grid point for 1976 was 3.6, 28, and 33 structures 

per square mile for wildland forest, mixed forest/agriculture, and intensive agriculture land classes, respectively (table 12). Although structure densities around 

wildland forest were higher in the Puget Sound area than the rest of western Washington, structure densities around intensive agriculture were highest in southwest 

Washington, particularly in 2006. Mean structure densities increased around all 

land classes over time, with twice the density around the wildland forest and mixed 

forest/agriculture land classes in 2006 than in 1976. Structure densities for all land 

classes was highly skewed, but indicate that the median density also increased over 

time (fig. 12).

Table 11—Median of elevation and slope for land use classes on nonfederal 

lands in Washington by side of state and year

Elevation Slope

Land use class 1976 1994 2006 1976 1994 2006

- - - - - Meters - - - - - - - - - - Percent - - - - -

Eastern Washington:

Wildland forest 889 895 898 18.1 18.4 18.4

Wildland range 533 534 536 7.9 7.9 8.0

Mixed forest/agriculture 697 699 698 7.3 7.7 7.7

Mixed range/agriculture 838 842 842 9.2 9.1 9.1

Intensive agriculture 541 539 539 3.8 3.8 3.8

Low-density residential 437 572 576 2.2 3.5 3.8

Urban 393 456 393 2.5 2.5 2.5

Other 195 195 195 0 0 0

Western Washington:

Wildland forest 199 208 214 14.8 15.4 15.7

Mixed forest/agriculture 80 79 80 2.9 3.0 3.1

Intensive agriculture 36 34 31 1.0 0.9 0.9

Low-density residential 81 85 88 4.4 4.5 4.6

Urban 68 73 74 2.7 2.7 2.7

Other 1 1 1 0 0 0

The number of 

structures around 

resource land uses 

doubled in western 

Washington.
24

GENERAL TECHNICAL REPORT PNW-GTR-881

Table 12—Density of structures in 80-ac circles around points in different land use classes, for nonfederal 

land in western Washington; means by area, land use class, and year

Structures Annual change in structures Change in structures

Land use class 1976 1994 2006 1976–1994 1994–2006 1976–2006

Number per square mile - - - - - - - - - - - - - Percent - - - - - - - - - - - - -

Puget Sound:

Wildland forest 5.5 8.0 11.3 2.20 2.84 208

Mixed forest/agriculture 27.6 45.6 55.5 2.93 1.57 201

Intensive agriculture 32.5 43.6 49.0 1.57 1.05 151

Low-density residential 126.8 151.5 191.1 1.11 1.69 151

Olympic Peninsula:

Wildland forest 2.6 3.6 4.8 2.14 1.96 184

Mixed forest/agriculture 30.7 42.4 54.7 2.23 1.66 178

Intensive agriculture 28.3 43.7 42.0 3.00 -0.26 149

Low-density residential 98.9 115.9 143.6 1.07 1.43 145

Southwest Washington:

Wildland forest 2.7 3.7 4.7 1.95 1.75 174

Mixed forest/agriculture 25.7 35.7 50.6 2.03 2.58 197

Intensive agriculture 35.0 44.6 59.1 1.53 2.03 169

Low-density residential 78.1 104.3 120.7 1.79 1.07 155

Western Washington totals:

Wildland forest 3.5 5.0 6.7 2.10 2.21 189

Mixed forest/agriculture 27.6 41.2 53.5 2.48 1.93 194

Intensive agriculture 32.5 43.9 50.8 1.76 1.16 157

Low-density residential 114.0 137.6 169.7 1.19 1.50 149

Structure density was substantially lower in eastern Washington than in western Washington. The mean density of structures counted in 80-ac circles around 

each eastern Washington photointerpretation grid point for 1976 was 1.0 structures 

per square mile for wildland forest and wildland range land classes (table 13). 

Structure density was somewhat greater in mixed forest/agriculture than intensive 

agriculture land classes, and substantially greater than in mixed range/agriculture. 

Although structure densities around wildland forest were greater in the Inland 

Empire area than in central Washington, the reverse was true for all other land 

classes. Mean structure densities increased around most land classes over time, 

with about twice the density around the wildland forest and mixed forest/agriculture land classes in 2006 than in 1976. Structure densities for all land classes were 

highly skewed, but unlike in western Washington, the median density increased 

only slightly over time for the mixed forest/agriculture and residential land classes 

(fig. 13).
25

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

Figure 12—Distribution of structure densities in western Washington around points on different land use classes for three dates. The 

top and bottom of the shaded boxes are the 75th and 25th percentiles, the thin line within each box is the median, the heavy dashed line 

is the mean, the whiskers are the 10th and 90th percentiles, and the points are the 5th and 95th percentiles. Note: y-axis scale differs 

among graphs, and box values equal zero for wildland forest.

Intensive agriculture

Year

1976 1994 2006

0

20

40

60

80

100

120

140

160

180

Mixed forest/agriculture

0

20

40

60

80

100

120

140

160

180

Low-density residential

1976 1994 2006

0

100

200

300

400

500

600

Wildland forest

Structure density (number/mi2 )

0

5

10

15

20

25

30

35

40

45
26

GENERAL TECHNICAL REPORT PNW-GTR-881

Table 13—Density of structures in 80-ac circles around points in different land use classes, for nonfederal 

land in eastern Washington; means by area, land use class, and year

Structures Annual change in structures Change in structures

Land use class 1976 1994 2006 1976–1994 1994–2006 1976–2006

Number per square mile - - - - - - - - - - - - - Percent - - - - - - - - - - - - -

Central Washington:

Wildland forest 0.5 1.0 1.3 3.22 2.70 247

Wildland range 0.5 1.0 1.3 3.40 2.33 245

Mixed forest/agriculture 8.4 11.7 15.5 1.66 2.73 186

Mixed range/agriculture 3.5 6.0 7.5 2.94 2.21 216

Intensive agriculture 9.2 10.5 11.0 0.70 0.44 120

Low-density residential 101.3 103.5 97.3 0.11 -0.62 96

Inland Empire:

Wildland forest 1.5 2.3 3.0 2.18 2.52 195

Wildland range 2.1 2.1 1.8 0.17 -1.68 87

Mixed forest/agriculture 7.1 10.8 12.8 2.38 1.49 179

Mixed range/agriculture 5.9 6.2 6.6 0.32 0.52 112

Intensive agriculture 3.1 3.3 3.7 0.32 0.87 117

Low-density residential 67.5 68.9 81.6 0.11 1.57 121

Eastern Washington totals:

Wildland forest 1.0 1.6 2.2 2.41 2.64 208

Wildland range 1.3 1.6 1.5 0.95 -0.29 117

Mixed forest/agriculture 7.3 10.9 13.1 2.28 1.62 180

Mixed range/agriculture 3.9 6.0 7.4 2.41 1.94 190

Intensive agriculture 4.4 4.8 5.2 0.46 0.65 118

Low-density residential 76.7 80.6 87.3 0.26 0.77 114

Points on resource land use classes with high structure counts within 80-ac 

circles were scattered around Washington (fig. 14). The highest structure densities around resource land use classes in western Washington, and the greatest 

increases in densities between 1976 and 2006, were within 1⁄4 mi of developed 

classes (fig. 15). Although the highest densities in eastern Washington were also 

within 1⁄4 mi of developed classes, changes in density were less dramatic and in 

some cases declined as land use of some resource land points changed to developed (fig. 16). 
27

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

Intensive agriculture

Year

0

10

20

30

40

Mixed forest/agriculture

0

10

20

30

40

50

60

Low-density residential

Year

0

100

200

300

400

Wildland forest

1976 1994 2006 1976 1994 2006

1976 1994 2006 1976 1994 2006

1976 1994 2006 1976 1994 2006

0

5

10

15

20

Wildland range

0

5

10

15

20

Mixed range/agriculture

0

10

20

30

Structure density (number/mi2 ) Structure density (number/mi2 ) Structure density (number/mi2 )

Figure 13—Distribution of structure densities in eastern Washington around points on different land use 

classes for three dates. The top and bottom of the shaded boxes are the 75th and 25th percentiles, the thin line 

within each box is the median, the heavy dashed line is the mean, the whiskers are the 10th and 90th percentiles, 

and the points are the 5th and 95th percentiles. Note: y-axis scale differs among graphs, and box values equal 

zero for three of the classes.
28

GENERAL TECHNICAL REPORT PNW-GTR-881

.

0 25 50 75 100 12.5

Kilometers

08–36>36Urban/low-density residential

Structures per square mile

Figure 14—Map of structure density classes around points in resource lands (forest, range, and agricultural classes) in 2006.
29

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

0

20

40

60

80

100

1976

1994

2006

Structure density (number/mi2 ) Structure density (number/mi2 ) Structure density (number/mi2 )

Land use class

Wildland forest Mixed 

forest/agriculture

Intensive

agriculture

Wildland forest Mixed 

forest/agriculture

Intensive

agriculture

Wildland forest Mixed 

forest/agriculture

Intensive

agriculture

0

20

40

60

80

1000

20

40

60

80

100

<1/4 mi

1/4 to 1 mi

>1 mi

<1/4 mi

1/4 to 1 mi

>1 mi

<1/4 mi

1/4 to 1 mi

>1 mi

Figure 15—Structure density around points in western Washington resource land use 

classes (forest land, agriculture, or mixed forest/agriculture) by distance to developed 

land use classes (low-density residential or urban) for three dates.
30

GENERAL TECHNICAL REPORT PNW-GTR-881

Figure 16—Structure density around points in eastern Washington resource land use classes (forest land, rangeland, 

agriculture, mixed forest/agriculture, or mixed range/agriculture) by distance to developed land use classes (low-density 

residential or urban) for three dates. Note: estimates for mixed range/agriculture are unreliable owing to low sample size.

0

10

20

30

40

50

60

0

10

20

30

40

50

60

0

10

20

30

40

50

60

1976

1994

Structure density (number/mi2 )

Land use class

Wildland 

forest

Wildland 

range

Mixed 

forest/

agriculture

Mixed 

range/

agriculture

Intensive

agriculture

<1/4 mi

1/4 to 1 mi

>1 mi

Structure density (number/mi2 ) Structure density (number/mi2 )

Wildland 

forest

Wildland 

range

Mixed 

forest/

agriculture

Mixed 

range/

agriculture

Intensive

agriculture

<1/4 mi

1/4 to 1 mi

>1 mi

2006

Wildland 

forest

Wildland 

range

Mixed 

forest/

agriculture

Mixed 

range/

agriculture

Intensive

agriculture

<1/4 mi

1/4 to 1 mi

>1 mi
31

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

In many cases, the structure densities around points in resource lands exceeded 

the expected values because many of the 80-ac circles included areas of developed 

land classes within them (table 14). Structure densities calculated for individual 

land use classes within those circles were lower than when all structures were 

assigned to the land use class at the center, particularly for wildland forest and 

range. For example, the density of structures in wildland forest in 2006 in eastern 

and western Washington was 0.5 and 0.4 per mi2, respectively (table 15), while the 

density in 80-ac circles around wildland forest points was 2.2 and 6.7, respectively. 

Both estimates provide complementary perspectives on the impact of housing and 

development on forest land. Nevertheless, mean densities were still quite high 

(>20 structures per mi2

) for intensive agriculture and mixed forest/agriculture in 

western Washington. Many of the high-housing-density agricultural resource lands 

in western Washington had visible evidence of open fields and tilling, but it is not 

clear whether crops or production differed from areas with low housing density. 

Density of structures within resource lands increased over time, although the rates 

were somewhat lower than when all lands classes in the 80 ac circles were included. 

Table 14—Percentages of 80-ac circles that were 

entirely in one land use class, by year

Land use class at center 1976 1994 2006

Percent

Eastern Washington:

Wildland forest 80.8 79.4 79.1

Wildland range 70.5 68.6 68.2

Mixed forest/agriculture 23.0 19.7 18.3

Mixed range/agriculture 43.8 43.8 39.8

Intensive agriculture 56.5 55.1 54.6

Low-density residential 11.6 14.7 15.5

Urban 22.6 21.9 26.7

Other 30.0 32.5 32.5

Western Washington: 

Wildland forest 82.2 81.7 81.7

Mixed forest/agriculture 26.5 19.7 16.6

Intensive agriculture 43.2 38.1 37.3

Low-density residential 16.1 20.7 24.3

Urban 49.0 50.3 51.3

Other 8.2 8.6 9.3

Increases in structures 

around forest points 

were primarily due 

to development in 

adjacent land uses.
32

GENERAL TECHNICAL REPORT PNW-GTR-881

Table 15—Density of structures found in different land use classes for nonfederal land in Washington; means 

by side of state, land use class, and year

Structures Annual change in structures Change in structures

Land use class 1976 1994 2006 1976–1994 1994–2006 1976–2006

Number per square mile - - - - - - - - - - - - - Percent - - - - - - - - - - - - -

Eastern Washington:

Wildland forest 0.23 0.34 0.48 2.20 3.15 211

Wildland range 0.16 0.22 0.28 1.75 2.25 178

Mixed forest/agriculture 6.53 8.63 10.01 1.58 1.29 153

Mixed range/agriculture 2.32 4.77 5.23 4.06 0.85 226

Intensive agriculture 3.11 3.34 3.65 0.38 0.81 117

Low-density residential 104.30 104.68 114.34 0.02 0.82 110

Urban 592.91 606.74 634.07 0.13 0.39 107

Western Washington:

Wildland forest 0.30 0.37 0.38 1.20 0.28 126

Mixed forest/agriculture 22.69 29.71 36.77 1.67 1.57 162

Intensive agriculture 23.74 28.63 31.81 1.11 0.81 134

Low-density residential 124.87 146.15 177.10 0.99 1.38 142

Urban 793.16 883.57 1107.20 0.68 1.61 140

Although federal forest lands managed by the Forest Service and National 

Park Service tend to be located in remote areas, the number of private structures 

around wildland forest points within 1 mi of their borders has increased over time. 

Structure densities doubled from 0.95 to 1.9 per mi2 within 1 mi of these federal 

lands between 1976 and 2006 in western Washington, and density increases were 

even higher in eastern Washington, from 1.1 to 2.7 per mi2 (fig. 17). This equates 

to an estimated 2,900 structures in western Washington and 5,000 in eastern 

Washington found on nonfederal forest land within 1 mi of federal land boundaries in 2006.

In 2006, most of the areas classified as urban land classes were contained 

in areas delineated by counties as Urban Growth Areas (UGA); the exceptions 

(45,000 and 20,000 ac in western and eastern Washington, respectively) appeared 

to consist of dense unincorporated suburban areas that met our land class density 

definitions (table 16). In western Washington, 98 percent of nonfederal lands 

in the wildland forest class was outside the UGAs, while the amounts for the 

mixed forest/agriculture and intensive agriculture classes were 91 and 93 percent, 

respectively. In eastern Washington, more than 99 percent of resource lands was 

outside the UGAs, except for mixed range/agriculture at 91 percent. The majority 

of lands classified as low-density residential was also outside of UGAs (82 percent 

and 88 percent for western and eastern Washington, respectively).
33

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

Figure 17—Structure density around points in wildland forest by distance to national forest or 

national park land for three dates.

0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

Eastern Washington Western Washington 

Distance to national forest or national park land

<1 mi >1 mi <1 mi >1 mi

1976

1994

2006

Structure density (number/mi2 )

Table 16—Area of nonfederal land in Washington in 2006 by land use class and Urban Growth Area (UGA) 

classification

Land use class Incorporated Not incorporated Not in UGA Total

Thousand Thousand Thousand Thousand acres Percent acres Percent acres Percent acres Percent

Eastern Washington:

Wildland forest 11.7 0.2 5.1 0.1 5,730.8 99.7 5,748 100

Wildland range 13.7 0.2 13.6 0.2 5,917.7 99.5 5,945 100

Mixed forest/agriculture 0.9 0.6 0.5 0.3 155.3 99.1 157 100

Mixed range/agriculture 0 0 5.8 8.9 58.7 91.1 64 100

Intensive agriculture 32.1 0.4 23.0 0.3 8,031.3 99.3 8,086 100

Low-density residential 53.3 7.4 29.9 4.1 639.4 88.5 723 100

Urban 243.7 81.6 34.9 11.7 20.0 6.7 299 100

Other 5.6 2.6 5.8 2.7 205.0 94.7 216 100

 Total 361.1 1.7 118.4 0.6 20,758.1 97.7 21,238 100

Western Washington:

Wildland forest 71.0 1.0 49.0 0.7 7,196.0 98.4 7,316 100

Mixed forest/agriculture 6.4 2.4 17.0 6.3 245.2 91.3 269 100

Intensive agriculture 26.7 3.9 23.5 3.4 633.0 92.6 683 100

Low-density residential 127.7 9.0 122.0 8.6 1,164.8 82.4 1,414 100

Urban 455.7 71.7 135.3 21.3 44.6 7.0 636 100

Other 5.1 11.3 1.8 4.1 37.9 84.6 45 100

 Total 692.5 6.7 348.7 3.4 9,322 90.0 10,362.8 100
34

GENERAL TECHNICAL REPORT PNW-GTR-881

Tree cover in urban areas in 2006 was 10 percent in eastern Washington and 20 

percent in western Washington. In eastern Washington, points that had been urban 

since 1976 had higher cover than points that were converted to urban since then, 

while the opposite was true for western Washington (fig. 18).

0

10

20

30

40

50

Tree cover (percent)

Eastern Washington Western Washington 

Duration of urban status

Urban 

1976

Urban 

1994

Urban 

2006

Urban 

1976

Urban 

1994

Urban 

2006

1976

1994

2006

Figure 18—Tree cover in 2.5-ac circles surrounding urban land class points for three dates, by side of 

state and duration in urban land class: urban 1976 was urban at all three dates, urban 1994 for the last 

two dates, and urban 2006 was urban at only the last date.

As expected, there were important differences between the land use classes in 

this study and the NLCD-classified satellite image cover types. In the forest land 

use class, 26 and 15 percent of the area were classified as shrubland or grassland 

cover types in eastern and western Washington, respectively (tables 17 and 18). In 

many cases, these cover types probably reflect dominance by nontree vegetation in 

recently harvested or disturbed stands, open forests, and misclassified hardwood 

trees. In western Washington, 2.5 percent of the forest land use class is in “open 

space development” NLCD cover, while in eastern Washington the figure is 0.6 

percent. Closer examination indicates that a GIS layer was used to convert a large 

number of forest logging roads to 30-m-wide developed strips, but only in western Washington, and regardless of whether the road was visible through the tree 

canopy.

Land use classes 

differed significantly 

from land cover 

classifications.
35

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

Table 17—Percentage of the area of western Washington in each land use class in different satellite-derived 

National Land Cover Database (NLCD) land cover categories

Mixed

NLCD land cover Forest agriculture/forest Agriculture Residential Urban Other

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - Percent - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Water 0.3 0.7 1.1 0.9 0.8 79.2

Ice/snow 0.1 0 0 0 0 3.7

Open space development 2.5 8.5 5.7 16.5 12.4 0

Low-density development 0.6 4.4 5.5 14.2 38.6 0

Medium-density development 0.1 0.4 1.1 1.7 25.9 0

High-intensity development 0 0.1 0.2 0.4 10.9 0

Barren 1.5 0.5 0.5 0.7 0.7 10.3

Deciduous forest 2.8 5.9 1.9 7.7 1.1 0

Conifer forest 69.0 14.0 2.2 19.5 3.1 1.0

Mixed forest 5.6 9.3 1.6 15.1 1.8 0

Shrubland 11.2 7.5 3.0 6.1 0.6 1.9

Grassland 3.5 8.1 3.0 4.9 1.1 1.3

Pasture/hay 0.2 24.5 47.2 6.5 1.4 0

Crops 0 1.5 13.5 0.3 0.2 0

Woody wetlands 2.2 9.2 5.9 4.0 0.6 0.1

Herbaceous wetlands 0.3 5.3 7.7 1.6 0.7 2.3

 Total 100.0 100.0 100.0 100.0 100.0 100.0

Table 18—Percentage of the area of eastern Washington in each land use class in different satellite-derived 

National Land Cover Database (NLCD) land cover categories

 Mixed Mixed

 agriculture/ agriculture/

NLCD land cover Forest Range forest range Agriculture Residential Urban Other

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - Percent - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Water 0.2 0.6 0.4 0.4 0.2 0.7 0.3 80.1

Ice/snow 0 1.5 0 0 0 0 0 2.9

Open space development 0.6 0 1.8 1.6 3.1 9.2 15.2 0.3

Low-density development 0.7 0.3 1.3 0.7 0.7 8.2 40.7 0.2

Medium-density development 0.1 0 0.1 0.2 0.1 2.1 26.6 0.1

High-intensity development 0 0 0 0 0 0.2 4.0 0

Barren 1.2 0.1 0 0 0 0.1 0 9.0

Deciduous forest 0.2 0.1 0.2 0.6 0.1 0.1 0 0

Conifer forest 69.7 0.9 31.7 4.4 1.0 22.9 1.6 0.9

Mixed forest 0.1 0 0 0 0 0.1 0 0

Shrubland 20.0 81.2 28.8 60.0 12.2 25.7 4.8 3.1

Grassland 6.0 10.6 25.2 21.3 3.8 10.3 1.4 2.4

Pasture/hay 0 0.5 2.4 2.4 3.9 5.8 1.5 0.1

Crops 0.3 3.1 5.1 6.7 73.9 12.5 3.5 0

Woody wetlands 0.5 0.3 1.2 0.6 0.3 0.9 0.1 0.4

Herbaceous wetlands 0.2 1.0 1.8 1.0 0.7 1.0 0.2 0.5

 Total 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0
36

GENERAL TECHNICAL REPORT PNW-GTR-881

The NLCD-estimated tree canopy cover varied with land use zone in western 

Washington, with more than 80 percent of the forest class having 30 m pixels with 

tree cover in >0 percent, while less than 20 percent of the intensive agriculture had 

tree cover >0 percent (fig. 19). Interestingly, more than 60 percent of the lowdensity residential class had tree cover, with 36 percent of the class having pixels 

with >80 percent tree cover. Thirty-eight percent of the urban class had pixels with 

tree cover. In eastern Washington, NLCD-estimated tree cover was much lower for 

nonforest land use points, with only 20 percent of the residential class points having 

>20 percent tree cover (fig. 20).

Wildland forest 

Mixed forest/agriculture

Intensive agriculture Urban 

Low-density residential Other 

Tree canopy cover percent (30 m pixel)

Percentage of land use class above canopy cover level

0

20

40

60

80

100

0 20 40 60 80 100

Figure 19—Reverse-cumulative distribution of National Land Classification Database-estimated tree cover by land use class 

for western Washington, showing the percentage of points with tree cover above the level shown on the x-axis. For example, 

20 percent of urban class points had tree canopy cover of 40 percent or more in the surrounding 2.5-ac area.
37

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

Tree canopy cover percent (30 m pixel)

Percentage of land use class above canopy cover level

0

20

40

60

80

100

Wildland forest

Wildland range 

Residential 

Urban 

Other 

Mixed forest/agriculture

Mixed range/agriculture

Intensive agriculture 

0 20 40 60 80 100

Figure 20—Reverse-cumulative distribution of National Land Classification Database-estimated tree cover by land use class for 

eastern Washington, showing the percentage of points with tree cover above the level shown on the x-axis. For example, 24 percent 

of mixed forest-agriculture class points had tree canopy cover of 40 percent or more in the surrounding 2.5-ac area.

Discussion

Substantial changes in land use and housing density occurred in Washington in the 

last 30 years. The state’s population increased by an estimated 2.5 million people 

(66 percent) between 1976 and 2006, with most of the increase around Puget Sound. 

During this time, an estimated 1.16 million ac were converted from forestry, range, 

and agriculture land uses to low-density residential and urban land uses (equivalent to conversion of a football field every 18 minutes). Despite similar increases 

in population between 1976 to 1994 and 1994 to 2006, the rate of conversion of 

resource lands to developed lands was greater prior to 1994 than afterward. In 

addition to conversion, the density of housing structures on lands that remained in 

resource land uses increased as well. Increases in housing density on resource lands 

were greater in the 1994 to 2006 period than in the 1976 to 1994 period in eastern 

The rate of conversion 

of resource lands to 

developed lands was 

greater prior to 1994 

than afterward.
38

GENERAL TECHNICAL REPORT PNW-GTR-881

Washington, but lower in western Washington. These patterns of change in population, land use, and structures indicate housing densification on resource lands 

without wholesale change in land use, and higher rates of densification in existing 

urban and residential areas in western Washington than in eastern Washington.

Most of the land converted to residential and urban uses in Washington was 

forest land. The conversion of 650,000 ac of forest land over the 30-year period 

represented a loss of 2.7 percent of the total wildland forest in Washington, but a 

loss of 4.7 percent of the nonfederal wildland forest. This represents a potentially 

large impact on the ability to produce forest products, because very little timber 

volume has been produced from federal lands since 1990. For example, only 4 

percent of the timber volume produced in Washington in 2010 came from federal 

lands (Washington State Department of Natural Resources 2012). Conversion 

of forest land to urban land uses also has an impact on wildlife and endangered 

species. Bilby and Mollot (2008) found that populations of Coho salmon in streams 

in the Puget Sound area declined by 75 percent in urbanizing areas while populations were stable elsewhere. Direct impacts to vegetation in riparian zones as well 

as pollution in runoff from impervious surfaces have been implicated in fishery 

declines (Morley and Karr 2002).

Changes in forest land ownership can be highly dynamic, and its transfer 

from public to private, or from industrial private to nonindustrial private owners, could set the stage for future development on those lands. This study did 

not address those issues, and looked only at ownership at one point in time. In 

localized geographic areas (e.g., the I-90 corridor through the Cascade Range), 

changes in ownership are likely to have a profound effect on development patterns. Although we found that most conversion of forest land happened on private 

nonindustrial ownerships, it is possible that those lands were previously in public 

or private industrial ownership. Although it would be good to investigate, it could 

be challenging to find the ownership information that aligns well with image dates 

(especially for the mid-90s images).

In addition to loss of land area, the increased proximity of developed land uses 

and housing structures to forest land may reduce timber production. For example, 

the likelihood of forest land being managed for timber production tends to decline 

as density of houses in the surrounding area increases (Kline et al. 2004, Wear et 

al. 1999). Although the overall population increase was lower in eastern Washington than in western Washington, increases in housing density on forest land were 

greater. This could be a cause of concern because wildfires are more common on 

the east side of the state, and changes in housing in the WUI can affect strategies 

and costs for controlling wildfires (Hammer et al. 2007).
39

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

Increased development also had substantial impacts on the area in agricultural 

land uses (i.e., mixed forest/agriculture, mixed range/agriculture, and intensive 

agriculture land classes). Statewide, agricultural land uses were a smaller portion of 

the land base than forest land, and experienced a comparable rate of conversion to 

developed uses (4 percent or 377,000 ac over the 30-year period). However, most of 

the loss of agricultural land occurred on the west side (264,000 ac), with an overall 

loss of 22 percent of the land area there. Other assessments estimate that more than 

1.4 million acres of farmland were lost between 1950 and 2007 in the Puget Sound 

region alone (Canty et al. 2012). Housing structure density also increased within 

these agricultural zones and lot sizes declined. The impact of lot sizes on agricultural productivity is unclear, however; production is often higher from small farm 

lots than from traditional larger farms, as long as there are not too many “recreational” farmers in the mix (Heimlich et al. 2001).

Most of the urban land use classes we delineated appear to be contained in 

the state-designated UGAs. However, much of the low-density residential land 

use is outside of those areas, and housing density has continued to increase there. 

Additional examination of changes in development with reference to county or 

local land use plans could provide insight into recent and potential future patterns 

of development.

Different definitions and metrics of land use change result in different estimates of rates of forest conversion to nonforest land uses for western Washington. 

The estimate from FIA field plots is a loss of 207,000 ac of nonfederal forest 

land between 1990 and 2005 (Gray et al. 2005, unpublished data), and 239,000 ac 

between 1980 and 1990 (MacLean et al. 1992), for an overall loss of 446,000 ac and 

a rate of 0.22 percent per year. This study found a loss of 493,000 ac between 1976 

and 2006 for an overall rate of 0.21 percent per year. In contrast, an effort to classify change with Landsat image classification suggested a loss of 1.2 million ac of 

forest land between 1988 and 2004, for an overall rate of 0.9 percent per year (Rural 

Technology Initiative 2006). Comparison of this image classification with inventory 

plots found substantial confusion between classifications of forest, agriculture, and 

developed land uses (Kline et al. 2009), with an apparent problem distinguishing 

recent clearcuts at lower elevations from land use change. For example, we found 

substantial areas classified by NLCD as shrubland and grassland in our forest land 

use class. However, when only the pixels classified as change from forest to developed use are considered, the estimate of forest loss in the Rural Technology Initiative report of 401,000 ac between 1988 and 2004 results in an estimated rate (0.30 

percent per year) that is only 38 percent higher than the estimate for the 30-year 

period in this study (0.21 percent per year) (Rural Technology Initiative 2006).
40

GENERAL TECHNICAL REPORT PNW-GTR-881

This method is promising for providing consistent trend information on land 

use over time. Human interpretation of landscape patterns in vegetation cover, 

roads, buildings, and landforms allows for much more nuanced interpretations of 

landscapes than is possible with computer algorithms. The structure counts provide 

more detail on location of people and houses than is possible otherwise (except 

perhaps with LiDAR). Most significantly, a consistent set of definitions and protocols was applied to the entire 30-year period, which has not been readily available 

in analyses of land use change to date. The scale at which polygons are mapped and 

the mix of classes that can occur in a polygon may be too coarse to estimate some 

site-specific impacts (e.g., on wildlife habitat). The delineation of the entire land 

area into land use polygons that can be updated as new imagery becomes available 

makes it possible to calculate change for relatively small areas. However, delineation of boundaries and polygon shapes is somewhat subjective, so the analyses 

based on grid points provides a more robust metric for change over time. 

It may be desirable to update this study to a fourth time period with new statewide imagery that is scheduled to be collected in 2014. In addition, imagery from 

the 1970s for the large nonforest zone in eastern Washington could be incorporated 

to provide a complete assessment of all land uses in the state over the last 30 years. 

Potential future applications of this study, in combination with inventory, environmental, or economic data, include (1) assessing changes in forest or agricultural 

management in areas close to residential areas or in proximity to housing structures; (2) analyzing fuels, fire risk, and housing density in fire-prone forests to aid 

in planning; (3) determining development patterns in relation to known or potential 

future flood zones; (4) examining the effectiveness of different land use planning 

approaches by comparing development patterns in areas with different policies; and 

(5) evaluating the effect of changes in parcel size on economic value, ecological 

value, and future development.

Acknowledgments

Thanks to Karen Ripley, Ken Pierce, Luke Rogers, and Charles Raines for reviews 

of this manuscript. Trevor Gamache and Donnych Diaz helped with image analysis 

and data collection. Funding for this study was provided by the Pacific Northwest 

Research Station and the national Forest Health Monitoring Program of the U.S. 

Forest Service.

This method is 

promising for providing consistent 

trend information on 

land use over time.
41

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

Metric Equivalents

1 foot (ft) = 0.3048 meter (m)

1 acre (ac) = 0.4047 hectare (ha)

1 square mile (mi2) = 2.59 square kilometers (km2

)

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GENERAL TECHNICAL REPORT PNW-GTR-881

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beyond: impacts on agriculture and rural land. Washington DC: U.S. Department 

of Agriculture, Economic Research Service. 80 p.

Homer, C.; Huang, C.; Yang, L.; Wylie, B.; Coan, M. 2004. Development of 

a 2001 national landcover database for the United States. Photogrammetric 

Engineering and Remote Sensing. 70: 829–840.

Kline, J.D.; Azuma, D.L.; Alig, R.J. 2004. Population growth, urban expansion, 

and private forestry in western Oregon. Forest Science. 50: 33–43.

Kline, J.D.; Moses, A.; Azuma, D.L.; Gray, A.N. 2009. Evaluating satellilte 

imagery-based land use data for describing forest land development in western 

Washington. Western Journal of Applied Forestry. 24: 214–222.

Lambin, E.F.; Turner, B.L.; Geist, H.J.; Agbola, S.B.; Angelsen, A.; 

Bruce, J.W.; Coomes, O.T.; Dirzo, R.; Fischer, G.; Folke, C.; George, 

P.S.; Homewood, K.; Imbernon, J.; Leemans, R.; Li, X.B.; Moran, E.F.; 

Mortimore, M.; Ramakrishnan, P.S.; Richards, J.F.; Skanes, H.; Steffen, 

W.; Stone, G.D.; Svedin, U.; Veldkamp, T.A.; Vogel, C.; Xu, J.C. 2001. The 

causes of land use and land-cover change: moving beyond the myths. Global 

Environmental Change-Human and Policy Dimensions. 11: 261–269.

Lettman, G.J.; Herstrom, A.A.; Hiebenthal, D.; McKay, N.; Robinson, T.J. 

2011. Land use change on nonfederal land in Oregon 1974–2009. Salem, OR: 

Oregon Department of Forestry. 69 p. http://www.oregon.gov/ODF/STATE_

FORESTS/FRP/docs/ForestFarmsPeople2009.pdf. (September 25, 2012).

Lund, H.G.; Thomas, C.E. 1989. A primer on stand and forest inventory designs. 

Gen. Tech. Rep. WO-54. Washington DC: U.S. Department of Agriculture, 

Forest Service. 96 p.

MacLean, C.D.; Bassett, P.M.; Yeary, G. 1992. Timber resource statistics for 

Western Washington. Resour. Bull. PNW-RB-191. Portland, Oregon: U.S. 

Department of Agriculture, Forest Service, Pacific Northwest Research Station. 

135 p.

MacLean, C.D.; Bolsinger, C.L. 1997. Urban expansion in the forests of the Puget 

Sound region. Resour. Bull. PNW-RB-225. Portland, OR: U.S. Department of 

Agriculture, Forest Service, Pacific Northwest Research Station. 17 p.

McKay, N.; Bassett, P.M.; MacLean, C.D. 1995. Timber resource statistics for 

eastern Washington. Resour. Bull. PNW-RB-201. Portland, OR: U.S. Department 

of Agriculture, Forest Service, Pacific Northwest Research Station. 47 p.
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Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

Morley, S.A.; Karr, J.R. 2002. Assessing and restoring the health of urban 

streams in the Puget Sound Basin. Conservation Biology. 16: 1498–1509.

Northwest Environment Watch. 2002. Sprawl and smart growth in greater 

Seattle-Tacoma. Seattle, WA: Northwest Environment Watch. http://www.

sightline.org/wp-content/uploads/downloads/2012/02/seattle_sprawl.pdf. 

(September 25, 2012).

Oswald, D.D. 1984. Timber resources in areas developed for nonforest use 

in western Washington. Resour. Bull. PNW-RB-112. Portland, OR: U.S. 

Department of Agriculture, Forest Service, Pacific Northwest Research 

Station. 20 p.

Powell, S.L.; Cohen, W.B.; Yang, Z.; Pierce, J.D.; Alberti, M. 2008.

Quantification of impervious surface in the Snohomish water resources 

inventory area of western Washington from 1972–2006. Remote Sensing 

of Environment. 112: 1895–1908.

Radeloff, V.C.; Hammer, R.B.; Stewart, S.I.; Fried, J.S.; Holcomb, S.S.; 

McKeefry, J.F. 2005. The wildland-urban interface in the United States. 

Ecological Applications. 15: 799–805.

Radeloff, V.C.; Stewart, S.I.; Hawbaker, T.J.; Gimmi, U.; Pidgeon, A.M.; 

Flather, C.H.; Hammer, R.B.; Helmers, D.P. 2010. Housing growth in and 

near United States protected areas limits their conservation value. Proceedings 

of the National Academy of Sciences of the United States of America. 

107: 940–945.

Rural Technology Initiative. 2006. Western Washington land use change. Seattle, 

WA: Rural Technology Initiative, University of Washington. 31 p. http://www.

ruraltech.org/projects/wwaluc. (April 21, 2008).

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County Population Estimates, Table GCT-T1. http://factfinder.census.gov/. 

(August 20, 2008).

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timber harvest 2010. Olympia, WA. http://www.dnr.wa.gov/Publications/ 

obe_wa_timber_harvest_report_2010.pdf. (September 25, 2012).

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growth on timber management and inventories in Virginia. Forest Ecology and 

Management. 188: 107–115.
44

GENERAL TECHNICAL REPORT PNW-GTR-881

Appendix

Table 19—Area of nonfederal land in Washington by county and percentages of total by 

area, land use class, and year

Land use class 1976 1994 2006

Thousand Thousand Thousand acres Percent acres Percent acres Percent

Adams County:

Wildland range 340 27.6 340 27.6 340 27.6

Intensive agriculture 874 71.0 874 71.0 874 71.0

Low-density residential 6 0.5 6 0.5 6 0.5

Urban 6 0.5 6 0.5 6 0.5

Other 6 0.5 6 0.5 6 0.5

 Total 1,232 100 1,232 100 1,232 100

Asotin County:

Wildland forest 65 28.2 65 28.2 64 27.8

Wildland range 161 46.9 161 46.9 161 46.9

Mixed forest/agriculture 7 3.0 7 3.0 7 3.0

Intensive agriculture 112 21.5 112 21.5 112 21.5

Low-density residential 10 0.4 10 0.4 1 0.6

Urban 0 0 9 0.2

 Total 354 100 354 100 354 100

Benton County:

Wildland forest 6 0.5 6 0.5 6 0.5

Wildland range 474 43.5 474 43.5 441 40.4

Intensive agriculture 491 45.1 491 45.1 520 47.7

Low-density residential 40 3.6 40 3.6 40 3.6

Urban 45 4.1 45 4.1 51 4.7

Other 34 3.1 34 3.1 34 3.1

 Total 1,090 100 1,090 100 1,090 100

Chelan County:

Wildland forest 205 53.8 200 52.4 197 51.7

Wildland range 105 27.5 100 26.2 98 25.7

Mixed forest/agriculture 1 0.4 0 0.1 0 0.1

Mixed range/agriculture 0 0.1 0 0

Intensive agriculture 39 10.3 35 9.2 32 8.4

Low-density residential 25 6.5 39 10.2 41 10.8

Urban 6 1.5 7 1.9 13 3.4

 Total 381 100 381 100 381 100

Clallam County:

Wildland forest 536 87.7 523 85.5 517 84.7

Mixed forest/agriculture 11 1.8 10 1.6 8 1.3

Intensive agriculture 30 4.9 23 3.7 16 2.7

Low-density residential 28 4.6 48 7.9 60 9.8

Urban 5 0.8 6 1.0 8 1.2

Other 1 0.2 1 0.2 1 0.2

 Total 611 100 611 100 611 100
45

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

Table 19—Area of nonfederal land in Washington by county and percentages of total by 

area, land use class, and year (continued)

Land use class 1976 1994 2006

Thousand Thousand Thousand acres Percent acres Percent acres Percent

Clark County:

Wildland forest 176 44.1 168 42.0 155 38.8

Mixed forest/agriculture 68 17.0 59 14.8 48 12.0

Intensive agriculture 81 20.2 70 17.4 51 12.9

Low-density residential 48 12.0 64 16.1 86 21.4

Urban 26 6.6 38 9.6 59 14.8

Other 0 0.1 0 0.1 0 0.1

 Total 400 100 400 100 400 100

Columbia County:

Wildland forest 87 55.1 86 54.5 86 54.5

Wildland range 59 6.0 59 6.0 59 6.0

Mixed forest/agriculture 3 2.1 3 2.1 3 2.1

Intensive agriculture 234 36.1 233 35.8 233 35.8

Low-density residential 0 0.3 2 1.2 2 1.2

Other 6 0.3 6 0.3 6 0.3

 Total 390 100 390 100 390 100

Cowlitz County:

Wildland forest 625 89.6 612 87.8 603 86.4

Mixed forest/agriculture 11 1.5 10 1.5 8 1.2

Intensive agriculture 15 2.2 15 2.2 13 1.9

Low-density residential 32 4.6 41 5.8 52 7.4

Urban 14 2.0 15 2.1 16 2.2

Other 1 0.1 5 0.7 6 0.9

 Total 697 100 697 100 697 100

Douglas County:

Wildland forest 14 12.2 14 12.2 14 12.2

Wildland range 538 47.2 538 47.2 531 46.9

Intensive agriculture 605 39.0 605 39.0 605 39.0

Low-density residential 1 1.2 1 1.2 8 1.6

Urban 7 0.4 7 0.4 7 0.4

 Total 1,165 100 1,165 100 1,165 100

Ferry County:

Wildland forest 828 88.2 823 87.7 819 87.3

Wildland range 28 3.0 28 3.0 28 3.0

Mixed forest/agriculture 38 4.0 37 4.0 37 3.9

Mixed range/agriculture 4 0.4 4 0.4 4 0.4

Intensive agriculture 26 2.8 26 2.7 25 2.7

Low-density residential 12 1.3 18 2.0 23 2.4

Urban 0 0 0 0 0 0

Other 2 0.2 2 0.2 2 0.2

 Total 939 100 939 100 939 100
46

GENERAL TECHNICAL REPORT PNW-GTR-881

Table 19—Area of nonfederal land in Washington by county and percentages of total by 

area, land use class, and year (continued)

Land use class 1976 1994 2006

Thousand Thousand Thousand acres Percent acres Percent acres Percent

Franklin County:

Wildland range 271 33.8 271 33.8 265 33.1

Intensive agriculture 488 60.9 488 60.9 494 61.7

Low-density residential 18 2.3 18 2.3 18 2.3

Urban 6 0.8 6 0.8 6 0.8

Other 18 2.3 18 2.3 18 2.3

 Total 801 100 801 100 801 100

Garfield County:

Wildland forest 21 21.9 21 21.9 21 21.9

Wildland range 66 23.0 66 23.0 66 23.0

Mixed forest/agriculture 1 1.0 1 1.0 1 1.0

Intensive agriculture 261 53.6 261 53.6 260 52.6

Low-density residential 0 0 1 1.0

Other 6 0.5 6 0.5 6 0.5

 Total 355 100 355 100 355 100

Grant County:

Wildland range 772 44.8 772 44.8 749 43.5

Mixed range/agriculture 6 0.3 6 0.3 6 0.3

Intensive agriculture 835 48.5 835 48.5 835 48.5

Low-density residential 40 2.3 40 2.3 52 3.0

Urban 6 0.3 6 0.3 17 1.0

Other 63 3.7 63 3.7 63 3.7

 Total 1,722 100 1,722 100 1,722 100

Grays Harbor County:

Wildland forest 985 91.2 983 90.9 981 90.8

Mixed forest/agriculture 8 0.8 9 0.8 7 0.7

Intensive agriculture 42 3.9 40 3.7 39 3.6

Low-density residential 32 3.0 33 3.1 36 3.4

Urban 9 0.8 12 1.1 13 1.2

Other 4 0.4 4 0.4 4 0.4

 Total 1,081 100 1,081 100 1,081 100

Island County:

Wildland forest 57 42.8 43 32.2 33 25.0

Mixed forest/agriculture 5 3.6 4 2.6 2 1.3

Intensive agriculture 26 19.7 24 18.1 24 17.8

Low-density residential 39 29.3 56 41.8 66 49.3

Urban 4 3.3 5 3.9 7 5.3

Other 2 1.3 2 1.3 2 1.3

 Total 134 100 134 100 134 100
47

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

Table 19—Area of nonfederal land in Washington by county and percentages of total by 

area, land use class, and year (continued)

Land use class 1976 1994 2006

Thousand Thousand Thousand acres Percent acres Percent acres Percent

Jefferson County:

Wildland forest 432 94.0 419 91.2 414 90.1

Mixed forest/agriculture 6 1.4 6 1.3 5 1.0

Intensive agriculture 6 1.4 6 1.4 6 1.4

Low-density residential 11 2.3 23 4.9 26 5.6

Urban 2 0.4 3 0.7 6 1.4

Other 2 0.5 2 0.5 2 0.5

 Total 460 100 460 100 460 100

King County:

Wildland forest 631 62.4 588 58.2 567 56.1

Mixed forest/agriculture 8 0.8 6 0.6 5 0.5

Intensive agriculture 59 5.8 47 4.6 39 3.9

Low-density residential 156 15.4 169 16.7 169 16.7

Urban 156 15.4 199 19.7 229 22.6

Other 2 0.2 2 0.2 2 0.2

 Total 1,011 100 1,011 100 1,011 100

Kitsap County:

Wildland forest 147 57.8 118 46.6 105 41.3

Mixed forest/agriculture 10 3.9 8 3.0 6 2.3

Intensive agriculture 1 0.4 1 0.4 1 0.4

Low-density residential 85 33.3 110 43.4 123 48.6

Urban 10 4.1 15 6.0 18 6.9

Other 1 0.5 1 0.5 1 0.5

 Total 254 100 254 100 254 100

Kittitas County:

Wildland forest 412 67.2 407 66.3 401 65.4

Wildland range 450 23.9 441 23.2 438 22.9

Mixed forest/agriculture 1 0.2 1 0.2 1 0.2

Intensive agriculture 130 6.9 129 5.7 115 5.3

Low-density residential 9 1.5 25 4.1 46 5.7

Urban 7 0.2 8 0.4 8 0.5

Other 6 0.1 6 0.1 6 0.1

 Total 1,017 100 1,017 100 1,017 100

Klickitat County:

Wildland forest 586 61.2 577 60.3 571 59.7

Wildland range 284 17.0 283 16.9 276 16.8

Mixed forest/agriculture 18 1.9 15 1.6 14 1.5

Mixed range/agriculture 4 0.5 4 0.4 4 0.4

Intensive agriculture 274 18.3 272 18.0 275 17.8

Low-density residential 7 0.8 22 2.4 33 3.4

Urban 3 0.4 3 0.4 4 0.4

Other 12 0.2 12 0.2 12 0.2

 Total 1,189 100 1,189 100 1,189 100
48

GENERAL TECHNICAL REPORT PNW-GTR-881

Table 19—Area of nonfederal land in Washington by county and percentages of total by 

area, land use class, and year (continued)

Land use class 1976 1994 2006

Thousand Thousand Thousand acres Percent acres Percent acres Percent

Lewis County:

Wildland forest 887 82.5 880 81.9 868 80.8

Mixed forest/agriculture 31 2.9 30 2.8 29 2.7

Intensive agriculture 109 10.1 106 9.9 105 9.8

Low-density residential 41 3.8 50 4.7 63 5.9

Urban 7 0.7 7 0.7 9 0.8

Other 0 0 0 0 0 0

 Total 1,075 100 1,075 100 1,075 100

Lincoln County:

Wildland forest 138 45.8 138 45.8 136 45.1

Wildland range 488 18.3 488 18.3 488 18.3

Mixed forest/agriculture 2 0.8 2 0.8 2 0.8

Mixed range/agriculture 1 0.3 1 0.3 1 0.3

Intensive agriculture 831 34.7 831 34.7 831 34.5

Low-density residential 0 0 2 0.8

Urban 6 0.2 6 0.2 6 0.2

 Total 1,467 100 1,467 100 1,467 100

Mason County:

Wildland forest 415 90.9 402 87.9 393 86.0

Mixed forest/agriculture 6 1.2 6 1.3 6 1.2

Intensive agriculture 4 0.8 3 0.7 3 0.7

Low-density residential 28 6.1 41 9.0 50 11.0

Urban 2 0.4 2 0.4 2 0.5

Other 3 0.6 3 0.6 3 0.6

 Total 457 100 457 100 457 100

Okanogan County:

Wildland forest 943 50.1 930 49.4 926 49.3

Wildland range 654 34.8 639 34.0 632 33.6

Mixed range/agriculture 49 2.6 50 2.7 50 2.7

Intensive agriculture 206 11.0 209 11.1 209 11.1

Low-density residential 21 1.1 45 2.4 55 2.9

Urban 5 0.3 6 0.3 6 0.3

Other 1 0.1 1 0.1 1 0.1

 Total 1,880 100 1,880 100 1,880 100

Pacific County:

Wildland forest 580 93.0 576 92.5 574 92.0

Mixed forest/agriculture 11 1.7 12 1.9 12 1.9

Intensive agriculture 9 1.4 9 1.4 8 1.3

Low-density residential 17 2.8 20 3.2 19 3.1

Urban 2 0.3 2 0.3 5 0.9

Other 5 0.8 5 0.8 5 0.9

 Total 623 100 623 100 623 100
49

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

Table 19—Area of nonfederal land in Washington by county and percentages of total by 

area, land use class, and year (continued)

Land use class 1976 1994 2006

Thousand Thousand Thousand acres Percent acres Percent acres Percent

Pend Oreille County:

Wildland forest 290 79.8 284 78.2 281 77.5

Mixed forest/agriculture 15 4.1 13 3.7 12 3.2

Intensive agriculture 41 11.4 41 11.2 40 10.9

Low-density residential 13 3.7 22 6.0 27 7.4

Urban 1 0.3 1 0.3 1 0.3

Other 3 0.8 3 0.8 3 0.8

 Total 363 100 363 100 363 100

Pierce County:

Wildland forest 467 61.8 424 56.1 400 53.0

Mixed forest/agriculture 55 7.3 41 5.4 34 4.5

Intensive agriculture 28 3.7 23 3.1 18 2.3

Low-density residential 136 18.0 174 23.0 188 24.9

Urban 69 9.1 92 12.2 114 15.1

Other 1 0.1 1 0.1 1 0.1

 Total 756 100 756 100 756 100

San Juan County:

Wildland forest 51 45.2 44 38.9 43 38.5

Mixed forest/agriculture 22 19.8 17 15.5 15 13.5

Intensive agriculture 16 14.7 13 11.9 12 10.7

Low-density residential 22 19.4 37 32.9 41 36.5

Other 1 0.8 1 0.8 1 0.8

 Total 112 100 112 100 112 100

Skagit County:

Wildland forest 446 72.0 435 70.1 432 69.6

Mixed forest/agriculture 24 3.9 19 3.1 17 2.8

Intensive agriculture 103 16.7 95 15.3 95 15.4

Low-density residential 32 5.2 50 8.0 54 8.7

Urban 10 1.6 17 2.8 17 2.8

Other 5 0.7 5 0.7 5 0.7

 Total 620 100 620 100 620 100

Skamania County:

Wildland forest 216 92.5 209 89.8 208 89.4

Mixed forest/agriculture 4 1.8 4 1.6 4 1.6

Intensive agriculture 3 1.2 2 1.0 2 1.0

Low-density residential 10 4.3 16 7.1 17 7.5

Urban 0 0.2 1 0.6 1 0.6

 Total 233 100 233 100 233 100
50

GENERAL TECHNICAL REPORT PNW-GTR-881

Table 19—Area of nonfederal land in Washington by county and percentages of total by 

area, land use class, and year (continued)

Land use class 1976 1994 2006

Thousand Thousand Thousand acres Percent acres Percent acres Percent

Snohomish County:

Wildland forest 455 64.1 402 56.7 379 53.4

Mixed forest/agriculture 18 2.5 14 2.0 12 1.6

Intensive agriculture 89 12.5 75 10.6 68 9.5

Low-density residential 98 13.8 150 21.2 168 23.7

Urban 47 6.6 64 9.0 80 11.3

Other 3 0.5 3 0.5 3 0.5

 Total 709 100 709 100 709 100

Spokane County:

Wildland forest 381 41.5 332 37.5 317 35.8

Wildland range 64 4.2 64 4.2 63 4.1

Mixed range/agriculture 39 4.4 31 3.5 27 3.1

Intensive agriculture 481 40.7 444 36.6 427 34.6

Low-density residential 86 8.2 159 16.4 190 19.9

Urban 75 0.9 96 1.7 101 2.4

Other 1 0.1 1 0.1 1 0.1

 Total 1,126 100 1,126 100 1,126 100

Stevens County:

Wildland forest 1,053 77.4 1,040 76.4 1,032 75.8

Wildland range 4 0.3 4 0.3 4 0.3

Mixed range/agriculture 56 4.1 53 3.9 52 3.8

Intensive agriculture 196 14.4 192 14.1 186 13.6

Low-density residential 47 3.5 65 4.8 81 6.0

Urban 4 0.3 6 0.4 6 0.4

Other 1 0.1 1 0.1 1 0.1

 Total 1,361 100 1,361 100 1,361 100

Thurston County:

Wildland forest 292 62.9 275 59.2 249 53.6

Mixed forest/agriculture 40 8.6 33 7.1 30 6.4

Intensive agriculture 57 12.3 50 10.7 39 8.5

Low-density residential 59 12.6 83 17.8 110 23.6

Urban 12 2.7 19 4.1 32 6.9

Other 5 1.0 5 1.0 5 1.0

 Total 465 100 465 100 465 100

Wahkiakum County:

Wildland forest 148 87.6 148 87.3 146 86.5

Mixed forest/agriculture 3 1.6 3 1.6 3 1.6

Intensive agriculture 15 8.6 15 8.6 15 8.6

Low-density residential 2 1.1 2 1.3 4 2.2

Other 2 1.1 2 1.1 2 1.1

 Total 169 100 169 100 169 100
51

Changes in Land Use and Housing on Resource Lands in Washington State, 1976–2006

Table 19—Area of nonfederal land in Washington by county and percentages of total by 

area, land use class, and year (continued)

Land use class 1976 1994 2006

Thousand Thousand Thousand acres Percent acres Percent acres Percent

Walla Walla County:

Wildland forest 44 24.9 44 24.9 44 24.9

Wildland range 150 6.7 150 6.7 150 6.7

Intensive agriculture 570 63.5 570 63.5 564 63.0

Low-density residential 11 2.9 11 2.9 17 3.5

Urban 12 0.8 12 0.8 12 0.8

Other 24 1.1 24 1.1 24 1.1

 Total 811 100 811 100 811 100

Whatcom County:

Wildland forest 264 53.2 251 50.6 248 50.0

Mixed forest/agriculture 25 5.1 20 4.1 19 3.9

Intensive agriculture 158 31.8 130 26.2 128 25.8

Low-density residential 38 7.6 76 15.4 81 16.4

Urban 10 2.1 18 3.5 18 3.7

Other 1 0.2 1 0.2 1 0.2

 Total 496 100 496 100 496 100

Whitman County:

Wildland forest 29 10.5 29 10.5 29 10.5

Wildland range 269 15.3 269 15.3 269 15.3

Intensive agriculture 1,047 72.3 1,047 72.3 1,047 72.3

Urban 13 0.8 13 0.8 13 0.8

Other 19 1.1 19 1.1 19 1.1

 Total 1,377 100 1,377 100 1,377 100

Yakima County:

Wildland forest 803 60.7 803 60.7 803 60.7

Wildland range 902 32.7 887 32.4 886 32.3

Intensive agriculture 433 4.8 417 4.4 405 4.3

Low-density residential 42 0.7 67 1.3 80 1.5

Urban 24 0.1 30 0.2 30 0.2

Other 13 1.0 13 1.0 13 1.0

 Total 2,218 100 2,218 100 2,218 100

Pacific Northwest Research Station

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