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FOR SALE BY U.S. GEOLOGICAL SURVEY

P.O. BOX 25286, DENVER, COLORADO 80225

1. COAST RANGE

Level IV Ecoregion Physiography Geology Soil Climate Potential Natural 

Vegetation

 Land Use and Land Cover

Area 

(square 

miles)

Elevation / 

Local Relief 

(feet)

Surficial material and bedrock Order (Great Groups) Common Soil Series Temperature / 

Moisture Regimes

Precipitation 

Mean annual 

(inches)

Frost Free

Mean annual 

(days)

Mean Temperature

January min/max; 

July min/max, ( ̊F)

986 Marine estuaries, terraces, sand dunes, and 

spits with low gradient, black water, meandering streams and rivers and shallow coastal 

lakes. Channelization and diking common.

0-300

/ 

10-180

Quaternary marine and non-marine terrace 

deposits, beach and dune sands, alluvium.

Spodosols (Haplorthods), 

Entisols (Fluvaquents), 

Inceptisols (Tropaquepts), 

Andisols (Fulvudands, 

Melanudands)

Bullards, Netarts, Coquille, Clatsop, 

Nestucca, Brenner, Lint, Quillamook. 

Very deep to deep, silty clay loam to 

sandy loam.

Isomesic/ 

Udic

60-85 200-240 36/50;

52/68

Sitka spruce, western hemlock, western 

red cedar, estuarine wetland plants.

Douglas-fir/western hemlock/Sitka spruce 

forests, wetlands. Dairy farms, urban/rural 

residential development, recreation, 

pastureland. 

2608 Coastal headlands and upland terraces with 

medium to high gradient, black-water 

streams.

0-500

/ 

100-1000

Quaternary glacial drift and marine 

sandstone.

Inceptisols (Haplumbrepts, 

Humitropepts), Andisols 

(Fulvudands)

Ozette, Lytell, Astoria, Templeton, 

Reedsport, Ecola, Tolovana. Mostly 

deep, silt loam.

Isomesic/ 

Udic

70-125 190-240 36/48;

52/68

Sitka spruce, western hemlock, western 

red cedar.

Douglas-fir/western hemlock/Sitka spruce/ 

western red cedar forests. Forestry, rural 

residential development, recreation.

1685 Low mountains with U-shaped valleys and 

high gradient streams. Higher areas were 

glaciated.

0-4000

/ 

800-2800

Lower Tertiary sandstone and siltstone. Andisols (Fulvudands) Snahopish, Solleks, Makah. Gravelly 

loam and very gravelly loam.

Mesic, 

Frigid/ 

Udic

80-200 180-230 30/45;

48/72

Western hemlock, western red cedar; 

some Douglas-fir. At higher elevations, 

Pacific silver fir. Most epiphytic-rich 

rainforest ecosystem in Ecoregion 1.

Western hemlock/western red cedar/Douglasfir/Pacific silver fir/red alder/ bigleaf maple 

forests. Forestry, recreation, some rural 

residential development.

3585 Steeply sloping mountains. High gradient, 

cascading streams and rivers occur and have 

stable summer flow.

0-5701

/ 

700-4000

Tertiary basaltic flows, pillow lavas, 

tuffaceous basalt, breccia, porphyritic basalt, 

basaltic sandstone/siltstone/conglomerate, 

concretionary marine siltstone, tuffaceous 

mudstone/siltstone/sandstone.

Andisols (Fulvudands, 

Hapludands), Ultisols 

(Palehumults)

Bunker, Knappton, Olympic, Raught, 

Hemcross, Klistan, Harslow, Caterl, 

Laderly, Murtip. Very deep to moderately deep, gravelly silt loam, silty clay 

loam, silt loam, loam, gravelly loam, 

very gravelly loam.

Frigid, 

Mesic/ 

Udic

70-200 100-190 30/46;

50/76

Western hemlock, western red cedar, 

Douglas-fir.

Douglas-fir/western hemlock/red alder/western 

red cedar forests. Forestry, rural residential 

development, recreation.

354 Undulating terraces and plateaus. Medium 

gradient, streams and rivers occur and have 

lower summer flow than elsewhere in 

Ecoregion 1.

20-1000

/

100-800

Pleistocene glacial outwash deposits. Andisols (Fulvudands) Hoquiam, Le Bar. Deep, silt loam. Mesic/ 

Udic

80-120 180-240 34/46;

50/75

Western hemlock, western red cedar; 

some Douglas-fir, red alder, bigleaf 

maple.

Douglas-fir/western hemlock/red alder/bigleaf 

maple/western red cedar forests. Hay farming, 

pasture, forestry, rural residential development.

2028 Low, rolling hills and mountains with medium 

gradient, sinuous streams and rivers. Low 

drainage density.

0-3020

/ 

300-1400 

Miocene sandstone, siltstone, shale. Andisols (Fulvudands, 

Hapludands), Alfisols 

(Hapludalfs), Inceptisols 

(Haplumbrepts, Dystrochrepts, 

Eutrochrepts, Fragiumbrepts)

Zenker, Elochoman, Vernonia, 

Scaponia, Goble, Braun, Anunde, 

Rinearson, Alstony. Mostly very deep 

to moderately deep, silt loam; some 

gravelly loam.

Mesic/ 

Udic

50-100 100-210 31/46;

50/76

Western hemlock, western red cedar, 

Douglas-fir.

Douglas-fir/western hemlock/red alder/western 

red cedar forests. Forestry, some rural 

residential development, pastureland.

3739 Moderately sloping, dissected mountains with 

medium to high gradient, sinuous streams.

300-2000

/ 

100-1500

Eocene marine sandstone, siltstone, 

mudstone, conglomerate.

Inceptisols (Dystrochrepts, 

Eutrochrepts, Haplumbrepts), 

Ultisols (Palehumults, 

Haplohumults)

Preacher, Bohannon, Digger, Blachly, 

Honeygrove, McDuff. Very deep to 

moderately deep, clay loam to gravelly 

loam.

Mesic/ 

Udic

60-130 110-200 32/48;

48/78

Western hemlock, western red cedar, 

Douglas-fir.

Douglas-fir/western hemlock/red alder/western 

red cedar forests. Forestry, pastureland in 

valleys, some rural residential development.

693 Dissected mountains with high gradient, 

sinuous streams and rivers. This ecoregion is 

part of the Siskiyou Mountains.

0-3400

/ 

800-1800

Cretaceous and Jurassic siltstone, shale, 

sandstone, conglomerate, graywacke, 

granite, diorite, serpentine.

Inceptisols (Dystrochrepts, 

Eutrochrepts, Haplumbrepts)

Etelka, Whobrey, Remote, Digger, Umpcoos, Rinearson. Very deep to shallow, 

silt loam to very gravelly sandy loam.

Mesic, 

Frigid/ 

Xeric

70-140 170-220 36/52;

52/76

Tanoak, Douglas-fir, western hemlock, 

Port Orford cedar.

Douglas-fir/western hemlock/tanoak/Port Orford 

cedar forests. Forestry, recreation, pasture-land 

in valleys, rural residential development.

31 Dissected coastal mountains and foothills 

with medium gradient, sinuous streams.

0-2000

/ 

1000-1800

Jurassic graywacke. Inceptisols (Humitropepts), 

Ultisols (Haplohumults)

Bosland, Floras, Loeb. Deep to 

moderately deep, well drained, silty 

clay loam to silt loam.

Isomesic/ 

Udic

80-95 190-280 38/50;

50/74

Coast redwood, Douglas-fir. Douglas-fir/coast redwood forests. Forestry, 

recreation, rural residential development.

9. EASTERN CASCADES SLOPES AND FOOTHILLS

Level IV Ecoregion Physiography Geology Soil Climate Potential Natural 

Vegetation

 Land Use and Land Cover

Area 

(square 

miles)

Elevation / 

Local Relief 

(feet)

Surficial material and bedrock Order (Great Groups) Common Soil Series Temperature / 

Moisture Regimes

Precipitation 

Mean annual 

(inches)

Frost Free

Mean annual 

(days)

Mean Temperature

January min/max; 

July min/max, ( ̊F)

1793 High, unglaciated plateaus, buttes, and 

canyons with medium to high gradient, 

permanent and intermittent streams and rivers. 

Springs occur especially in the south.

2500-5000

/ 

400-2000

Pleistocene and Miocene basalt flows. Alfisols (Haploxeralfs), 

Inceptisols (Xerochrepts), 

Mollisols (Haploxerolls, 

Argixerolls)

Satus, Jumpe, Sutkin, Sapkin. Stony to 

very stony loam.

Frigid/Xeric; 

Mesic at 

lower 

elevations

16-35 90-130 18/35;

52/82

Ponderosa pine, bitterbrush, Oregon 

white oak, Douglas-fir.

Open ponderosa pine and bitterbrush; some 

Douglas-fir and Oregon white oak. Forestry, 

recreation, and grazing. Mainly Yakima Nation 

land.

974 High, glaciated plateaus and mountains with 

high gradient, permanent streams and rivers. 

Scattered glacial rock-basin lakes.

2200-6500

/ 

600-2000

Pleistocene and Miocene andesite and basalt 

flows.

Andisols (Vitrixerands, 

Vitricryands), Inceptisols 

(Xerumbrepts), Mollisols 

(Haploxeralfs), Spodosols 

(Cryorthods)

Yallani, Bins, Bindle, Ketchly, 

Nomlas, Twolakes, Stirrup. Loam, 

sandy loam, gravelly sandy loam, 

gravelly loam, stony loam.

Frigid/Xeric; 

Udic at 

higher 

elevations

35-55 50-90 16/32;

47/77

Grand fir, Douglas-fir. Grand fir/Douglas-fir forests; some ponderosa 

pine. Forestry, recreation and a regional water 

source. Mostly publicly owned; some Yakima 

Nation land.

1024 Foothills, low mountains, plateaus, and 

valleys with permanent and intermittent, 

mostly medium gradient, streams and rivers.

500-3500

/

400-2000

Pleistocene basalt; Miocene Columbia River 

basalt.

Alfisols (Haploxeralfs), 

Mollisols (Haploxerolls), 

Inceptisols (Xerochrepts)

Underwood, McGowan, Gunn, 

Wamic, Hesslan, Skyline. Mostly very 

deep to moderately deep, loam, stony 

loam, very cobbly loam.

Mesic/ 

Xeric

16-40 90-140 26/40;

53/82

Douglas-fir, ponderosa pine, Oregon 

white oak, grasslands.

In the east: oak woodlands and ponderosa pine. In 

the west: Douglas-fir and western hemlock. Some 

grasslands also occur. Common land uses include 

forestry, recreation, grazing, rural residential 

development, orchards, and, in the valleys, grain 

and hay farming. Mostly privately owned land.

1077 High, undulating plateaus and canyons with 

permanent, medium gradient streams. Stream 

flow consistent year around due to volcanicinfluenced hydrogeology.

2800-5200

/

250-1800

Mt. Mazama ash; Pleistocene and Pliocene 

olivine basalt, olivine bearing andesite.

Andisols (Vitrixerands) Sisters, Wanoga, Fremkle, Allingham, 

Circle. Well drained, loamy sand to 

gravelly sandy loam that is often 

derived from ash.

Frigid/ 

Xeric

16-35 50-90 20/40;

40/82

Ponderosa pine, bitterbrush. Mainly ponderosa pine and bitterbrush. 

Common land uses include forestry, grazing, 

and recreation. Most of the land is owned by the 

public or the Warm Springs Nation.

4224 High, undulating volcanic plateau with 

isolated buttes and permanent and 

intermittent, low to medium gradient streams. 

Spring fed creeks, marshes, and a few lakes.

4500-8295

/ 

200-1800 

Mt. Mazama ash and pumice; Pleistocene 

basalt and andesite; Miocene olivine basalt.

Andisols (Vitricryands) Shanahan, Lapine, Steiger, Maset, Yawhee. Very deep to moderately deep, well 

drained to excessively drained, coarse 

sandy loam to gravelly loamy coarse 

sand that is often derived from pumice.

Cryic/ 

Xeric

16-30 10-50 14/37; 

38/80

On flats and depressions where pumice 

deposits are thickest: lodgepole pine. 

On slopes: ponderosa pine.

Lodgepole pine and ponderosa pine forests. 

Forestry and grazing. Most of the land is owned 

by the public.

641 High elevation basins with forested wetlands, 

marshes, lakes, reservoirs. Medium to low 

gradient rivers are important habitat for 

migratory waterfowl. Extensive marsh areas 

in the south. High ground water tables in the 

La Pine Basin.

4500-5000

/ 

20-500

Thick Mt. Mazama ash deposits, semiconsolidated lacustrine and fluvial sediments 

of Pleistocene age.

Andisols (Cryaquands, 

Vitricryands), Mollisols 

(Cryaquolls)

Tutni, Sunriver, Wickiup. Mucky silt 

loam, loamy sands, sandy loam.

Cryic/ 

Aquic

20-25 10-50 12/38;

38/80

La Pine Basin: lodgepole pine and wet, 

forested wetlands. Sycan and Klamath 

marshes: wetland vegetation.

Wetland meadow vegetation (e.g. tules, tufted 

hairgrass), lodgepole pine stands, and forested 

wetlands (e.g. willow and lodgepole pine). 

Grazing, rural residential, wood cutting, duck 

hunting, and recreation. A mix of publicly and 

privately owned land.

1040 Floodplains, terraces, and pluvial lake basins 

with low-gradient streams. Historically 

abundant wetlands. Many have been drained 

for agriculture.

4000-4900

/ 

30-300

Unconsolidated and semi-consolidated 

lacustrine and fluvial sediments of Holocene 

and Pleistocene age.

Histosols (Borohemists), Aridisols 

(Haplodurids), Inceptisols 

(Humaquepts), Mollisols 

(Haploxerolls, Endoaquolls, 

Argixerolls, Durixerolls),

Andisols (Cryaquands) 

Lather, Henley, Tulana, Kirk, 

Lakeview, Ozamis, Drews, Deter, 

Salisbury. Often very deep to deep, 

peaty muck, clay loam, silt loam, 

Mesic/ 

Xeric

10-18 90-120 21/39;

51/85

Big sagebrush, bunchgrass, wetland 

plants (tules, cattails, sedges).

Sagebrush, bunchgrass, some wetlands. 

Cropland, pastureland, and rural residential 

development. Mainly privately owned land.

1665 Steeply to moderately sloping mountains and 

high plateaus with mostly high gradient, 

intermittent streams. Also, reservoirs, a few 

glacial rock-basin lakes, numerous springs.

5000-8000

/ 

800-2000

Miocene basalt, rhyolite, tuffaceous lava 

flows, sandstone, siltstone.

Mollisols (Argixerolls, 

Haploxerolls), Andisols 

(Vitrixerands)

Winterim, Royst, Mound, 

Woodchopper, Rogger, Polander. Very 

deep to moderately deep, sandy loam 

to stony loam.

Cryic, 

Frigid/ 

Xeric

15-40 30-70 15/38; 

42/85

At lower elevations: ponderosa pine, 

white fir. At higher elevations: 

whitebark pine.

Ponderosa pine/white fir forests occur; some 

lodgepole pine, juniper, whitebark pine. 

Elevation, slope angle, and slope aspect affect 

vegetation types. Common land uses include 

forestry, grazing, and recreation. Mainly 

publicly owned land.

516 Gentle to moderate sloping mountains with 

permanent and intermittent, medium to high 

gradient streams. A few permanent and 

intermittent lakes with associated wetlands. 

Springs in the west.

3600-6300

/ 

500-2700

Miocene basaltic andesite. Mollisols (Cryoborolls, 

Argixerolls)

Woodcock, Pokegema, Pinehurst, 

Greystoke. Deep, loam to stony loam.

Cryic, 

Frigid/ 

Xeric

25-40 30-70 20/34; 

47/82

Ponderosa pine. At higher elevations: 

white fir.

Ponderosa pine forests occur; white fir, Shasta 

red fir, and Douglas-fir grow at higher 

elevations. Common land uses include forestry, 

grazing, and recreation. Mainly publicly owned 

land.

785 Undulating hills, benches, and escarpments 

with intermittent and permanent, medium 

gradient streams. A few small plateau lakes 

occur but reservoirs are more common.

4400-6200

/ 

250-1800

Miocene olivine basalt, tuffaceous sandstone, 

siltstone.

Mollisols (Argixerolls, 

Haploxerolls)

Lorella, Nuss, Merlin, Royst, 

Winterim. Stony clay loam, loam, very 

stony loam, gravelly loam, very 

gravelly loam.

Mesic, 

Frigid/ 

Xeric

12-20 60-120

77. NORTH CASCADES

Level IV Ecoregion Physiography Geology Soil Climate Potential Natural 

Vegetation

 Land Use and Land Cover

Area 

(square 

miles)

Elevation / 

Local Relief 

(feet)

Surficial material and bedrock Order (Great Groups) Common Soil Series Temperature / 

Moisture Regimes

Precipitation 

Mean annual 

(inches)

Frost Free

Mean annual 

(days)

Mean Temperature

January min/max; 

July min/max, ( ̊F)

1998 Low mountains and broad, glaciated valleys 

with permanent, medium gradient, glacial-fed 

rivers and streams. Reservoirs and glacial 

lakes.

400-3400

/ 

1200-3000

Mesozoic and Paleozoic conglomerates, 

slate, graywacke.

Andisols (Haplocryands), 

Spodosols (Humicryods, 

Duricryods)

Getchell, Kindy, Potchub. Deep to 

moderately deep, silt loam, gravelly 

silt loam.

Mesic, 

Frigid/ 

Udic

60-90 120-200 30/43; 

49/76

Western hemlock, western red cedar, 

Douglas-fir.

Mainly western hemlock/Douglas-fir/western 

red cedar forests. Forestry is the dominant land 

use; rural residential development, recreation, 

and valley grazing also occurs. A mix of 

publicly and privately owned land.

3140 Steep, glaciated ridges; with permanent, 

cascading glacial streams and glacial rockbasin lakes. Some rock outcroppings.

2800-6400

/ 

2600-3600

In west: Paleozoic sandstone and slate. 

In east: Tertiary and pre-Cretaceous schist.

Spodosols (Duricryods, 

Haplocryods), Histosols 

(Cryofolists)

Reggad, Altapeak, Chinkmin. Very 

deep to moderately deep, sandy loam, 

gravelly sandy loam, very cobbly 

muck.

Frigid, 

Cryic/ 

Udic

60-120 80-120 25/42; 

47/71 

Pacific silver fir, mountain hemlock, 

western hemlock; some subalpine fir.

Extensive forests composed primarily of Pacific 

silver fir and mountain hemlock. Common land 

uses include forestry and recreation. Most of the 

land is in public ownership.

1671 High mountain peaks with bare rock, glaciers, 

cirques. Permanent, high gradient, sedimentladen, glacial meltwater streams and glacial 

rock-basin lakes. 

5500-10775

/ 

1500-2200

Recent volcanics; Tertiary and preCretaceous gneiss and schist; Mesozoic 

granitic rocks and marine sedimentary 

rocks.

Spodosols (Haplocryods), 

Inceptisols (Cryumbrepts), 

Andisols (Vitricryands)

Undifferentiated, bare rock and rubble. Cryic/ 

Udic

80-140 40-70 13/36; 

42/62

Herbaceous and shrub alpine meadow 

vegetation; some mountain hemlock, 

subalpine fir, subalpine larch.

Alpine meadows, bare rock, glaciers, 

snowfields, some subalpine forests. Wilderness 

recreation is a common land use. Most of the 

land is publicly owned and is a regional water 

source.

1165 High, glaciated ridges, plateaus, and U-shaped 

valleys with numerous wetlands. Small glacial 

rock-basin lakes and both permanent and 

intermittent, high gradient streams.

4000-7882

/ 

1800-3600 

Tertiary and pre-Cretaceous metamorphic 

rocks; Mesozoic marine sandstone, shale, 

granitic rock.

Inceptisols (Cryochrepts, 

Cryumbrepts)

Myerscreek, Devore, Crocamp. Fine 

sandy loam to very stony sandy loam.

Cryic/ 

Xeric

25-65 50-90 8/27; 

45/70

Mixed subalpine fir with subalpine 

spruce, lodgepole pine in the northeast. 

At lower elevations: some Douglas-fir. 

At higher elevations: whitebark pine, 

subalpine fir.

Forests, forestry, wilderness recreation, grazing, 

and some mining. The land is mainly publicly 

owned and serves as a regional water source.

1171 Rounded mountains, ridges, and U-shaped 

valleys with medium to high gradient, 

permanent and intermittent streams and rivers. 

Some alpine glacial rock-basin lakes and 

irrigation storage reservoirs.

2500-5500

/ 

1400-3000

Mesozoic marine sandstone, shale, granitic 

rocks; pre-Cretaceous gneiss and schist.

Inceptisols (Xerochrepts), 

Alfisols (Haploxeralfs)

Watony, Siegel. Very deep to deep, 

very stony coarse sandy loam, gravelly 

loam.

Frigid, 

Cryic/ 

Xeric

10-35 80-110 12/30; 

50/80

Ponderosa pine and Douglas-fir. At 

high elevations: some subalpine fir. 

Common understory in the north: 

Idaho fescue. Common understory in 

the south: bluebunch wheatgrass.

Mostly woodland. Common land uses include 

forestry, recreation, grazing, rural residential 

development. A mix of publicly and privately 

owned land.

435 Steep, glaciated mountains and ridges with 

medium to high gradient rivers and streams. 

A few glacial rock-basin lakes.

1200-6094

/ 

2000-4000 

Thick deposits of volcanic ejecta (tephra); 

Miocene basalt; Cretaceous mixed 

metamorphic and igneous rocks; 

Precambrian gneiss and schist.

Andisols (Vitrixerands), 

Inceptisols (Xerochrepts), 

Alfisols (Haploxeralfs)

Bonner, Eloika, Roslyn, Martella, 

Natkim, Choralmont, Palmich, Ramparter. Very deep to deep, often tephradominated, silt loam, gravelly silt loam, 

sandy loam, cindery sandy loam, 

gravelly sandy loam. Fine ashy surface.

Mesic, 

Frigid/ 

Xeric

16-35 80-110 18/30; 

48/78

Mainly ponderosa pine and Douglasfir; some grand fir and subalpine fir on 

higher ridge crests.

Forest. Common land uses include recreation, 

forestry, and grazing. Most of the land is 

publicly owned. 

742 Steep, glaciated, mountains, ridges, and Ushaped valleys with mostly high gradient 

streams and rivers. A few glacial rock-basin 

lakes.

1100-6500

/ 

2400-5400

Pre-Tertiary and Cretaceous gneiss and 

schist; Mesozoic granitic rocks and 

serpentine.

Andisols (Vitricryands), 

Spodosols (Haplocryods)

Totem, Wedge, Esmeralda. Sandy 

loam, cindery sandy loam, bouldery 

sandy loam. Often ashy.

Frigid, 

Cryic/ 

Xeric

25-55 75-105 16/32;

48/76

Douglas fir, grand fir, subalpine fir, 

pine grass; some lodgepole pine, 

ponderosa pine, Englemann spruce.

Coniferous forest with wilderness recreation 

activity occurring. The land is mostly publicly 

owned and is a regional water source.

795 Low mountains, hills, cuestas, and V-shaped 

valleys with a trellis drainage pattern. The 

permanent and intermittent streams have steep 

gradients and high sediment loads. Glacial 

basins often contain lakes and were formed by 

alpine glaciation. South of the continental 

glacial limit.

2000-5200

/ 

400-3200

Paleocene to Cretaceous arkose with 

interbedded conglomerate, sandstone, 

siltstone.

Inceptisols (Xerochrepts), 

Alfisols (Haploxeralfs), 

Spodosols (Cryohumods)

Index, Nard, Ardenmont. Loam to 

loamy sand. Tends to be shallow in the 

south and deeper in the north.

Mesic, 

Frigid/ 

Xeric

15-40 75-120 18/34; 

50/81

Ponderosa pine, Douglas-fir, grand fir, 

bitterbrush, pinegrass, some subalpine 

fir.

Mostly coniferous woodland with forestry, 

recreation, grazing, some rural residential 

development. A mix of publicly and privately 

owned land.

596 Steep, glaciated mountains with cirques, 

alpine glaciers, persistent snow pack, bare 

rock, cascading glacier-fed streams, and 

glacial rock-basin lakes.

3000-7965

/ 

2400-3800 

Lower Tertiary sandstone and siltstone. Spodosols (Cryorthods),

Entisols (Cryorthents)

Undifferentiated soils, bare rock, 

rubble.

Frigid, 

Cryic/ 

Udic, 

Xeric

70-250 80-120 34/24; 

44/68

Mountain hemlock, Pacific silver fir, 

subalpine meadows. On the xeric soils 

of rainshadow areas in the northeast: 

subalpine fir.

Subalpine coniferous forests and meadows with 

bare rock, glaciers, snowfields, and wilderness 

recreational activity occurring. It is a regional 

water source.

21/40; 

49/83

In south: juniper. In north: a mix of 

ponderosa pine and juniper. Also 

bunchgrass and both low and big 

sagebrush.

Mosaic of pastures and woodland; some 

forestry and recreational activity. Its reservoirs 

are important to lowland irrigation. A mix of 

publicly and privately owned land.

78. KLAMATH MOUNTAINS

Level IV Ecoregion Physiography Geology Soil Climate Potential Natural 

Vegetation

 Land Use and Land Cover

Area 

(square 

miles)

Elevation / 

Local Relief 

(feet)

Surficial material and bedrock Order (Great Groups) Common Soil Series Temperature / 

Moisture Regimes

Precipitation 

Mean annual 

(inches)

Frost Free

Mean annual 

(days)

Mean Temperature

January min/max; 

July min/max, ( ̊F)

285 Terraces and floodplains in mountain valleys. 

Streams and rivers are perennial.

1100-1800

/ 

100-600

Holocene fluvial terrace and floodplain 

deposits.

Mollisols (Haploxerolls, 

Argixerolls), Alfisols 

(Palexeralfs), Inceptisols 

(Xerochrepts, Endoaquepts)

On floodplains: Newberg, Camas, 

Evans. On valley terraces: Medford, 

Foehlin, Central Point. On fans: Ruch, 

Barron, Clawson. Deep to very deep, 

silty clay loam to gravelly loam.

Mesic/ 

Xeric

 20-60 120-180 31/47; 

51/89

Oregon white oak, madrone, California 

black oak, ponderosa pine, grasslands.

A mix of orchards, cropland, pastureland, oak 

woodland, pine woodland, towns, rural 

residential development.

818 Moderately sloping mountain foothills with 

reservoirs and perennial and intermittent 

streams and rivers.

1500-4000

/ 

600-2000

In the east: Eocene basaltic lava flows. In the 

west: Jurassic sandstone and shale.

Mollisols (Haploxerolls, 

Argixerolls), Inceptisols 

(Xerochrepts), Vertisols 

(Haploxererts)

Medco, McMullin, McNull, Brader, 

Debenger, Carney. Mostly moderately 

deep, clay, cobbly clay loam, loam, 

gravelly loam.

Mesic/ 

Xeric

25-45 110-160 28/45; 

50/87

Ponderosa pine, Douglas-fir, Oregon 

white oak, California black oak, 

madrone.

Drier areas east of Medford: dominated by oak 

woodlands and ponderosa pine. Wetter areas: 

Douglas-fir and incense cedar. A mix of 

grazing, rural residential development, 

orchards, some cropland, and some forestry.

921 Narrow interior valleys, terraces, and 

foothills.

450-2000

/ 

400-1550

Holocene fluvial terrace deposits; Pliocene 

marine sandstone; Eocene basalt.

Mollisols (Haploxerolls, 

Argixerolls, Argiaquolls), 

Alfisols (Haploxeralfs), 

Inceptisols (Xerochrepts)

On terraces: Conser, Newberg, Roseburg. On foothills: Oakland, Sutherlin, 

Nonpareil. Mostly moderately deep to 

very deep, silty clay loam to loam.

Mesic/ 

Xeric

30-50 120-180 34/49; 

53/84

Oregon white oak, Douglas-fir, 

ponderosa pine, madrone.

A mix of oak woodlands and coniferous forests 

intermingle with pastureland, vineyards, 

orchards, row crops, rural residential 

development, and towns.

441 Highly dissected mountains with permanent 

and intermittent, high gradient streams.

1500-4200

/ 

1000-2200

Jurassic ultramafic rocks. Alfisols (Haploxeralfs), 

Inceptisols (Xerochrepts)

Pearsoll, Dubakella, Eightlar, Perdin, 

Gravecreek. Stony clay loam to cobbly 

loam.

Mesic, 

Frigid/ 

Xeric, 

Udic

45-140 70-140 32/44; 

49/82

Jeffrey pine, tanoak, Douglas-fir. 

Unique understory species and sparse 

woodland vegetation caused by soils 

derived from underlying serpentine.

Sparse woodland with unique understory 

vegetation. Common land uses include back 

country recreation, forestry, and mining. 

Ecoregion 78d is a regional water source.

2610 Highly dissected mountains with permanent 

and intermittent streams. A few small lakes at 

higher elevations.

1000-6000

/ 

1000-2800

Jurassic granitic rocks, shale, sandstone. Alfisols (Haploxeralfs), 

Inceptisols (Xerochrepts), 

Ultisols (Haploxerults)

Vannoy, Caris, Offenbacher, Josephine, 

Beekman, Kanid, Siskiyou, Tethrick. 

Deep to moderately deep, silt loam to 

gravelly loam.

Mesic, 

Frigid/ 

Xeric

35-70 90-160 29/44; 

50/86

Douglas-fir, ponderosa pine, Oregon 

white oak, incense cedar, grand fir.

Coniferous forests. Forestry, recreation, rural 

residential development, and mining. Ecoregion 

78e is a regional water source.

853 Highly dissected mountains with perennial 

and intermittent, high gradient streams and a 

few small, alpine glacial lakes.

1000-4800

/ 

1000-2700

Cretaceous and Jurassic conglomerate, 

sandstone, siltstone.

Inceptisols (Xerochrepts, 

Dystrochrepts), Ultisols 

(Palehumults, Palexerults)

Fritsland, Bravo, Cassiday, Deadline, 

Barkshanty, Nailkeg, Jayar, Althouse, 

Skymor, Atring, Kanid, Acker. Mostly 

moderately deep to very deep, very 

gravelly silt loam to very gravelly 

loam. On benches and ridge tops: 

moderately deep, silty clay loams.

Mesic, 

Frigid/ 

Udic, 

Xeric

70-130 100-190 38/50; 

50/76

Tanoak, Douglas-fir; some Port Orford 

cedar and Jeffrey pine.

Forests composed primarily of tanoak and 

Douglas-fir are common. Land uses include 

forestry, recreation, rural residential 

development and some mining.

122 Highly dissected mountains with perennial 

and intermittent, high gradient streams.

3800-7000

/ 

1000-3000

Miocene and Oligocene basaltic and 

andesitic flows; Jurassic granitic rocks.

Mollisols (Argixerolls, 

Haploxerolls)

Skookum, McMullin, McNull. Loam 

to very cobbly loam.

Mesic/ 

Xeric

25-35 90-160 24/42; 

49/88

Higher elevations and north-facing 

slopes: Douglas-fir, white fir, Shasta 

red fir. Lower elevations and southfacing slopes: ponderosa pine, western 

juniper, chaparral.

Coniferous forest, woodlands, savanna, and 

chaparral. Common land uses include forestry 

and recreation.

4. CASCADES

Level IV Ecoregion Physiography Geology Soil Climate Potential Natural 

Vegetation

 Land Use and Land Cover

Area 

(square 

miles)

Elevation / 

Local Relief 

(feet)

Surficial material and bedrock Order (Great Groups) Common Soil Series Temperature / 

Moisture Regimes

Precipitation 

Mean annual 

(inches)

Frost Free

Mean annual 

(days)

Mean Temperature

January min/max; 

July min/max, ( ̊F)

6302 Westerly trending ridges and valleys with 

reservoirs and medium gradient rivers and 

streams. U-shaped, glaciated valleys in the 

east.

800-4000

 /

 400-3000

Oligocene-Eocene andesitic, basaltic, and 

rhyolitic lava flows and breccia.

Inceptisols (Haplumbrepts), 

Ultisols (Haplohumults, 

Palehumults), Andisols 

(Haploxerands)

Klickitat, Kinney, McCully, Peavine, 

Honeygrove, Orford, Olympic, Cinebar. 

Very deep to deep, clay loam, silty clay 

loam, silt loam, gravelly clay loam, 

gravelly silt loam, cobbly loam.

Mesic/ 

Udic 

60-90 120-180 31/41; 

47/78

Western hemlock, western red cedar, 

Douglas-fir.

Douglas-fir/western hemlock/western red 

cedar/vine maple/red alder forests are widespread. Forestry and recreation are 

important land uses and pastureland occurs in 

lower valleys.

4557 Steep, glaciated, dissected mountains and 

ridges with high to medium gradient streams 

and glacial rock-basin lakes.

2800-5900

/ 

2000-3100

Oligocene-Miocene andesitic and basaltic 

lava flows and breccia.

Inceptisols (Haplumbrepts), 

Andisols (Hapludands, 

Fulvicryands, Haplocryands)

Keel, Hummington, Aschoff, Bull 

Run, Illahee, Mellowmoon. Very deep 

to moderately deep, silt loam, gravelly 

silt loam, gravelly loam, cobbly loam.

Frigid, 

Cryic/ 

Udic

70-120 80-120 26/37; 

44/75

Pacific silver fir, western hemlock, 

mountain hemlock, Douglas-fir; some 

noble fir. Ecoregion 4b is higher in 

elevation than Ecoregion 4a and is 

snow influenced.

Extensive Pacific silver fir/western hemlock/ 

Douglas-fir/mountain hemlock/noble fir/subalpine fir/grand fir/white fir forests. Common 

land uses include forestry and recreation. Ecoregion 4b is an important regional water source.

2219 High, undulating, volcanic plateau punctuated 

by buttes and cones. Sinuous, medium 

gradient streams flow through the glaciated 

landscape. Numerous glacial rock basin lakes. 

Small lakes on collapsed lava flows. Wetland 

areas are found in southwestern Washington 

Cascades.

4000-6500

/ 

500-2500

Pleistocene-Pliocene basaltic and andesitic 

lava flows, breccia, pyroclastic deposits; 

some Pleistocene alpine glacial deposits.

Spodosols (Haplocryods, 

Humicryods), Andisols 

(Fulvicryands), Inceptisols 

(Cryandepts)

Lastance, Talapus, Thader, Mt. Hood, 

Dinzer, Vanson, Sinnice, Tradedollar. 

Very gravelly silt loam, stony fine 

sandy loam, sandy loam, very cobbly 

loam.

Cryic/ 

Udic

55-100 30-90 21/35; 

43/72

Mountain hemlock, Pacific silver fir; 

some grand fir, noble fir.

Forests composed of mountain hemlock, Pacific 

silver fir, Englemann spruce, and lodgepole 

pine are extensive. Land uses include backcountry recreation and some forestry. 

Ecoregion 4c is an important regional water 

source.

719 High, glaciated, volcanic peaks with 

cascading streams, glacial cirques, and tarns. 

Active snowfields and glaciers more common 

to the north. Active and dormant volcanoes.

5600-14410 

/

1600-8000 

Pleistocene basalt and andesite; some alpine 

glacial deposits.

Entisols (Cryorthents) Bare rock, rubble. Cryic/ 

Udic, 

Peradic

75-140 0-30 16/31; 

38/65

Herbaceous and shrubby subalpine 

meadow vegetation; scattered 

mountain hemlock, subalpine fir 

stands.

Bare rock, glaciers, subalpine meadows, and 

forests. Land uses include back-country 

recreation. Ecoregion 4d is an important 

regional water source.

916 High, undulating plateau punctuated by 

volcanic peaks and affected by alpine 

glaciation. Many glacial rock-basin lakes 

occur. Its intermittent and permanent streams 

have medium to high gradients.

4000-8208

/

700-2500

Pleistocene alpine glacial deposits; Pliocene 

and Miocene andesite and olivine basalt.

Andisols (Vitricryands), 

Mollisols (Cryoborolls), 

Inceptisols (Cryochrepts), 

Spodosols (Haplocryods)

Woodcock, Oatman, Otwin, Lapine, 

Winopee, Steiger. Very deep to deep, 

very gravelly and stony loam to 

gravelly loamy coarse sand.

Cryic/ 

Udic

45-70 70-100 23/37; 

44/74

Mountain hemlock, lodgepole pine, 

Pacific silver fir; some grand fir, white 

fir, Shasta red fir.

Mostly coniferous forest with some bare rock at 

higher elevations. Land uses include backcountry recreation and some forestry and 

grazing.

1594 Highly dissected mountains with a few small 

lakes and high to medium gradient streams 

and rivers.

1000-5300

/

1200-2800

Tertiary pyroclastic rocks, basalt and 

basaltic andesite lava flows, breccia, tuff, 

sandstone, siltstone.

Ultisols (Palehumults), 

Inceptisols (Haplumbrepts)

Orford, Honeygrove, Gustin, Klickitat, 

Harrington, Kinney, Illahee, 

Scaredman, Mellowmoon. Very deep to 

moderately deep, clay loam, gravelly 

clay loam, gravelly silt loam, very 

gravelly loam, extremely gravelly loam, 

cobbly loam.

Mesic, 

Frigid/ 

Udic

50-80 80-180 32/42; 

49/82

Grand fir, white fir, western hemlock, 

Pacific silver fir, Douglas-fir; some 

Shasta red fir, mountain hemlock.

Douglas-fir/white fir/western hemlock/ Pacific 

silver fir/Shasta red fir/mountain hemlock 

forests. Land uses include forestry and 

recreation. Ecoregion 4f is an important 

regional water source.

1049 Mountains with moderate slopes, broad 

valleys, and medium to high gradient streams 

and rivers. Reservoirs, a few large mountain 

plateau lakes of glacial origin, and a high 

number of intermittent streams.

2600-5800

/

400-2400

Pliocene basalt and basaltic andesite. Alfisols (Haploxeralfs), Inceptisols 

(Xerochrepts, Xerumbrepts), 

Ultisols (Palexerults), Mollisols 

(Argixerolls)

Freezener, Geppert, Straight, Farva, 

Pinehurst, Dumont, Coyata. 

Moderately deep to deep, loam, 

gravelly loam, very cobbly loam.

Mesic, 

Frigid/ 

Xeric

45-60 90-120 26/45; 

47/85

White fir, Douglas-fir, ponderosa pine; 

some Shasta red fir, mountain 

hemlock.

Extensive rather open conifer forests with white 

fir often common. Douglas-fir and ponderosa pine 

are prevalent at low elevations and Shasta red fir 

grows at high elevations. Land uses include 

forestry, recreation, and some grazing. Ecoregion 

4g is an important regional water source. 

2. PUGET LOWLAND

Level IV Ecoregion Physiography Geology Soil Climate Potential Natural 

Vegetation

 Land Use and Land Cover

Area 

(square 

miles)

Elevation / 

Local Relief 

(feet)

Surficial material and bedrock Order (Great Groups) Common Soil Series Temperature / 

Moisture Regimes

Precipitation 

Mean annual 

(inches)

Frost Free

Mean annual 

(days)

Mean Temperature

January min/max; 

July min/max, ( ̊F)

344 Undulating glacial drift plains, terraces, and 

floodplains with low gradient, meandering 

streams and rivers.

0-400

/ 

50-300

Holocene alluvium; Pleistocene glacial drift. Spodosols (Haplorthods), 

Alfisols (Umbraqualfs)

Lynden, Hale, Tromp, Whatcom, 

Labounty. Silty to sandy loam.

Mesic/ 

Udic

33-55 150-210 33/44;

50/73

Western hemlock, western red cedar; 

some red alder, bigleaf maple, black 

cottonwood, Douglas-fir.

Pastureland, dairy farms, hay farming, 

urban/rural residential development. Some 

riparian deciduous forests.

677 Floodplains and terraces with meandering 

rivers, oxbow lakes, and meander scars. 

Freshwater and estuarine wetlands occur but 

were more common in the past.

0-800

/ 

100-600

Fine, Holocene fluvial sediments. Entisols (Fluvaquents), 

Inceptisols (Xerochrepts)

Skagit, Sumas, Sultan. Deep, fertile, 

silt loam.

Mesic/ 

Xeric

32-40 160-220 34/44;

52/75

Western red cedar, western hemlock; 

some red alder, black cottonwood, 

bigleaf maple, Sitka spruce.

Cropland and pastureland (often on reclaimed 

wetland), rural residential/suburban/urban/ 

industrial activity. Some riparian deciduous 

woodland, coniferous forests, wetlands.

218 Glacial scoured islands with small 

intermittent streams and limited surface 

water.

0-2400

/

150-2000

Mesozoic and Paleozoic sedimentary rock. Spodosols (Haplorthods), 

Alfisols (Palexeralfs), Inceptisols 

(Xerochrepts), Andisols 

(Melanoxerands, Vitraquands)

Roche, San Juan, Pickett, Bow, 

Coveland. Very gravelly silt loam to 

gravelly loam.

Mesic/ 

Xeric

20-35 160-226 36/46;

52/62

Douglas-fir, grand fir; some oak 

woodlands, grasslands, red cedar.

Coniferous forests, some oak woodlands. Crop 

and pastureland, recreation, rural residential 

development, towns.

758 Rolling glacial till plains with small, low to 

medium gradient streams. Drainage patterns 

are often deranged or internal. Fresh water 

supplies are limited in the east.

0-1800

/

300-1000

Pleistocene Vashon glacial ground moraine 

deposits.

Inceptisols (Durochrepts, 

Xerochrepts), Spodosols 

(Haplorthods)

Whidbey, Hoypus (on Whidbey 

Island), Elwha, Clallam, Catla. 

Moderately deep, gravelly sandy loam 

to very gravelly loamy sand.

Mesic/ 

Xeric

10-40 160-230 36/45;

51/64

Western hemlock, western red cedar, 

Douglas-fir; some grasslands, grand fir.

Pasture and cropland, woodland dominated by 

Douglas-fir. Forestry, rural residential 

development.

1142 Rolling moraines and foothills with lakes and 

sinuous streams and rivers.

0-2677

/

500-2000

Pleistocene Vashon glacial moraine deposits; 

Tertiary sedimentary rock.

Inceptisols (Durochrepts, 

Xerochrepts), Andisols 

(Vitrixerands)

Tokul, Alderwood, Everett. Very 

gravelly sandy loam to gravelly loam.

Mesic/ 

Xeric, 

Udic

35-65 145-200 32/43;

50/72

Western hemlock, western red cedar; 

some Douglas-fir.

Douglas-fir and western hemlock forests. 

Forestry, pastureland and cropland, rural 

residential/suburban/urban development.

1698 Undulating glacial drift plains with lakes and 

small, sinuous streams. Coastline is 

irregularly shaped. It is characterized by 

many bays and some cliffs.

0-1000

/

200-1000

Pleistocene drift, Vashon glacial till. Inceptisols (Durochrepts, 

Xerochrepts)

Alderwood, Harstine, Poulsbo, 

Ragnar. Deep, well drained, gravelly 

sandy loam; also fine sandy loam.

Mesic/ 

Xeric

35-70 160-210 35/44;

52/75

Western hemlock, western red cedar, 

Douglas-fir; some red alder, bigleaf 

maple.

Urban/suburban/industrial activity especially in 

east. Elsewhere, Douglas-fir/western hemlock 

forests, forestry, limited agriculture, rural 

residential development.

809 Nearly level to rolling glacial outwash and till 

plains with low gradient streams and lakes.

0-900

/ 

200-500

Pleistocene Vashon glacial outwash and till 

deposits.

Inceptisols (Durochrepts, 

Xerumbrepts), Andisols 

(Melanoxerands)

Alderwood, Everett, Spanaway, 

Nisqually. Deep, moderately well 

drained to somewhat excessively well 

drained, gravelly loam, gravelly sandy 

loam, very gravelly sandy loam, loamy 

fine sand.

Mesic/ 

Xeric

40-55 150-210 34/46;

52/77

Douglas-fir, prairies; some oak 

woodland, western hemlock, red cedar.

Douglas-fir/western hemlock forests, prairies, 

oak woodlands. Forestry, hay farming, 

pastureland. Mix of military and private land 

ownership.

437 Low, rolling to steeply sloping hills with 

medium to high gradient streams. Unaffected 

by continental Vashon glaciation.

300-1200

/

400-800

Pleistocene alpine glacial deposits; Tertiary 

sandstone and siltstone; Eocene andesite.

Ultisols (Palehumults), Alfisols 

(Palexeralfs)

Olympic, Melbourne, Buckpeak, Centralia. Very deep, well drained to very 

well drained, silty clay loam to loam.

Mesic/ 

Xeric

50-60 150-200 33/45;

50/76

Western hemlock, western red cedar; 

some Douglas-fir, bigleaf maple.

Douglas-fir and western hemlock forests. 

Forestry, rural residential development, hay 

farming, pastureland.

357 Rolling terraces and floodplains with 

meandering streams and oxbow lakes. 

Unaffected by continental Vashon glaciation.

150-800

/

200-500

Holocene alluvial deposits; Pleistocene 

alpine glacial outwash material.

Ultisols (Palehumults), Alfisols 

(Palexeralfs, Glossaqualfs), 

Mollisols (Argiaquolls)

Salkum, Prather. On prairies: Lacamas. 

On floodplains: Reed. Very deep to 

deep, silty clay loam to silt loam.

Mesic/ 

Xeric

45-55 150-220 35/47;

52/78

Western red cedar, western hemlock; 

some Douglas-fir, bigleaf maple, oak 

woodlands, prairies.

Pastureland, cropland, rural residential 

development, some coniferous and deciduous 

forests, forestry.

3. WILLAMETTE VALLEY

Level IV Ecoregion Physiography Geology Soil Climate Potential Natural 

Vegetation

 Land Use and Land Cover

Area 

(square 

miles)

Elevation / 

Local Relief 

(feet)

Surficial material and bedrock Order (Great Groups) Common Soil Series Temperature / 

Moisture Regimes

Precipitation 

Mean annual 

(inches)

Frost Free

Mean annual 

(days)

Mean Temperature

January min/max; 

July min/max, ( ̊F)

574 Undulating terraces and floodplains with low 

gradient, meandering streams. Numerous 

wetlands, oxbow lakes and ponds. 

0-300

/ 

20-250

Pleistocene unconsolidated and semiconsolidated, glacial/fluvial deposits in a 

fault block basin.

Mollisols (Haplaquolls, Argixerolls, Endoaquolls), Inceptisols 

(Xerochrepts, Fragiumbrepts), 

Alfisols (Glossudalfs, 

Haploxeralfs)

Sauvie, Rafton, Hillsboro, Gee, Dollar, 

Multnomah, Latourell, Quatama. 

Deep, silty clay loam to loam.

Mesic/ 

Xeric

37-50 165-210 34/45; 

56/80

Prairies (maintained by Native 

American burning), Oregon white 

oak, Douglas-fir, Oregon ash, alder, 

western red cedar.

Urban/suburban/rural residential/industrial 

activity, pastureland, nursery crops.

675 Floodplains with low gradient, incised, 

strongly meandering rivers and associated 

oxbow lakes/meander scars.

40-500

/ 

10-80

Holocene and Pleistocene fluvial sediments. Mollisols (Haploxerolls, 

Endoaquolls), Vertisols 

(Endoaquerts)

Cloquato, Newberg, Chehalis, Wapato, 

Waldo, Bashaw. Very deep to deep, 

fertile, silty clay loam to fine sandy 

loam.

Mesic/ 

Xeric

40-50 165-210 33/46; 

50/85

Cottonwood, alder, Oregon ash, 

bigleaf maple, Douglas-fir.

Vegetable and fruit farming, pastureland, 

urban/suburban/rural residential development, 

forested riparian areas, flood control.

1971 Nearly level to undulating fluvial terraces with 

sluggish, meandering streams and rivers. 

Historically, seasonal wetlands and ponds were 

common. Many streams now channelized.

160-500

/ 

10-150

Pleistocene lacustrine and fluvial 

sedimentary deposits.

Alfisols (Albaqualfs), Mollisols 

(Argialbolls, Argixerolls), 

Inceptisols (Xerochrepts)

Woodburn, Aloha, Willamette, 

Dayton, Amity, Concord, Malabon, 

Coburg, Salem. Very deep to deep, 

silty clay loam to silt loam.

Mesic/ 

Xeric

40-50 165-210 33/46; 

51/85

Oregon white oak, prairies 

(maintained by Native American 

burning). In wetter areas: Oregon 

ash, Douglas-fir.

Grass seed, grain farming (often on reclaimed 

wetland). Also urban/rural residential 

development and some forested riparian zones.

2527 Rolling foothills with medium gradient, 

sinuous streams.

10-1500

/ 

400-1000

Miocene andesitic basalt and marine 

sandstone.

Alfisols (Haploxeralfs), Ultisols 

(Haplohumults, Palehumults), 

Mollisols (Haploxerolls), 

Inceptisols (Fragiumbrepts)

Bellpine, Jory, Nekia, Hazelair, 

Willakenzie, Laurelwood, Cascade. 

Moderately deep to very deep, silty 

clay loam to silt loam.

Mesic/ 

Xeric

40-60 165-210 32/46; 

50/80

On drier sites: Oregon white oak and 

madrone. In moister areas: Douglasfir more common. Some western red 

cedar.

Rural residential development, pastureland, 

coniferous and deciduous forests, forestry, 

vineyards, Christmas tree farms, orchards.

Summary Table: Characteristics of Ecoregions of Western Washington and Oregon

1a. 

1b. 

1c. 

1d. 

1e. 

1f. 

1g. 

1h. 

1i. 

4a. 

4b. 

4c. 

4d. 

4e. 

4f. 

4g.

2a. 

2b. 

2c. 

2d. 

2e. 

2f. 

2g.

2h.

2i. 

3a. 

3b. 

3c. 

3d. 

Coastal Lowlands

Coastal Uplands

Low Olympics

Volcanics

Outwash

Willapa Hills

Mid-Coastal 

Sedimentary

Southern Oregon 

Coastal Mountains

Redwood Zone

Western Cascades 

Lowlands and 

Valleys

Western Cascades 

Montane 

Highlands

Cascade Crest 

Montane Forest

Cascades 

Subalpine/Alpine

High Southern 

Cascades Montane 

Forest

Umpqua Cascades

Southern 

Cascades

Fraser Lowland

Eastern Puget 

Riverine 

Lowlands

San Juan Islands

Olympic 

Rainshadow

Eastern Puget 

Uplands

Central Puget 

Lowland

Southern Puget 

Prairies

Cowlitz/Chehalis 

Foothills

Cowlitz/Newaukum 

Prairie Floodplains

Portland/ 

Vancouver Basin

Willamette River 

and Tributaries 

Gallery Forest

Prairie Terraces

Valley Foothills

Yakima Plateau 

and Slopes

Grand Fir Mixed 

Forest

Oak/Conifer 

Eastern Cascades 

Columbia 

Foothills

Ponderosa 

Pine/Bitterbrush 

Woodland

Pumice Plateau 

Forest

Cold Wet 

Pumice Plateau 

Basins

Klamath/Goose 

Lake Warm Wet 

Basins

North Cascades 

Lowland Forests

North Cascades 

Highland Forests

North Cascades 

Subalpine/ 

Alpine

Pasayten/ 

Sawtooth 

Highlands

Okanogan 

Pine/Fir Hills

Chelan Tephra 

Hills

Wenatchee/ 

Chelan 

Highlands

Chiwaukum 

Hills and 

Lowlands

High Olympics

Fremont 

Pine/Fir Forest

Southern 

Cascades Slope

Klamath 

Juniper/

Ponderosa Pine 

Woodland

Rogue/Illinois 

Valleys

Siskiyou 

Foothills

Umpqua Interior 

Foothills

Serpentine 

Siskiyous

Inland Siskiyous

Coastal 

Siskiyous

Klamath River 

Ridges

9a.

9b.

9c.

9d.

9e.

9f.

9g.

77a.

77b.

77c. 

77d. 

77e.

77f.

77g.

77h.

77i. 

9h.

9i.

9j.

78a.

78b.

78c.

78d. 

78e.

78f.

78g.