Soil Survey of Cowlitz County, Washington...100—Kelso silt loam, 0 to 8 percent slopes.....125....

United StatesDepartment ofAgriculture

NaturalResourcesConservationService

In cooperation withWashington StateDepartment of NaturalResources andWashington StateUniversity AgriculturalResearch Center

Soil Survey ofCowlitz County,Washington

USDA, NRCSSoil SurveyThis version of the soil survey of Cowlitz County, Washington, was created in 2006 for electronic publication.

General Soil Map

The general soil map, which is a color map, shows the survey area divided into groups of associated soils calledgeneral soil map units. This map is useful in planning the use and management of large areas.

To find information about your area of interest, locate that area on the map, identify the name of the map unit in thearea on the color-coded map legend, then refer to the section General Soil Map Units for a general description ofthe soils in your area.

Detailed Soil Maps

The detailed soil maps can be useful in planning the use andmanagement of small areas.

To find information about your areaof interest, locate that area on theIndex to Map Sheets. Note thenumber of the map sheet and turnto that sheet.

Locate your area of interest onthe map sheet. Note the map unitsymbols that are in that area. Turnto the Contents, which lists themap units by symbol and nameand shows the page where eachmap unit is described.

The Contents shows which tablehas data on a specific land use foreach detailed soil map unit. Alsosee the Contents for sections ofthis publication that may addressyour specific needs.

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How To Use This Soil Survey

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Additional information about the Nation’s natural resources is available on theNatural Resources Conservation Service home page on the World Wide Web. Theaddress is http://www.nrcs.usda.gov.

This soil survey is a publication of the National Cooperative Soil Survey, a joint effortof the United States Department of Agriculture and other Federal agencies, Stateagencies including the Agricultural Experiment Stations, and local agencies. TheNatural Resources Conservation Service (formerly the Soil Conservation Service) hasleadership for the Federal part of the National Cooperative Soil Survey.

Major fieldwork for this soil survey was completed in 1983. Soil names anddescriptions were approved in 1988. Unless otherwise indicated, statements in thispublication refer to conditions in the survey area in 1988. This survey was madecooperatively by the Natural Resources Conservation Service and the WashingtonState Department of Natural Resources and Washington State University AgriculturalResearch Center. The survey is part of the technical assistance furnished to the CowlitzCounty Soil and Water Conservation District.

Soil maps in this survey may be copied without permission. Enlargement of thesemaps, however, could cause misunderstanding of the detail of mapping. If enlarged,maps do not show the small areas of contrasting soils that could have been shown at alarger scale.

Since the publication of this survey, more information on soil properties may havebeen collected, new interpretations may have been developed, or existing interpretivecriteria may have been modified. The most current soil information and interpretationsfor this survey are in the Field Office Technical Guide (FOTG) at the local field office ofthe Natural Resources Conservation Service. The soil maps in this publication are indigital form. The digitizing of the maps was completed in accordance with the SoilSurvey Geographic (SSURGO) database standards. The digital SSURGO-certifiedmaps are considered the official maps for the survey area and are part of the FOTG atthe local field office of the Natural Resources Conservation Service.

The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programsand activities on the basis of race, color, national origin, age, disability, and whereapplicable, sex, marital status, familial status, parental status, religion, sexualorientation, genetic information, political beliefs, reprisal, or the fact that all or a part ofan individual’s income is derived from any public assistance program. (Not all prohibitedbases apply to all programs.) Persons with disabilities who require alternative means forcommunication of program information (Braille, large print, audiotape, etc.) shouldcontact USDA’s TARGET Center at (202) 720-2600 (voice and TDD). To file a complaintof discrimination, write to USDA, Director, Office of Civil Rights, 1400 IndependenceAvenue, S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice) or(202) 720-6382 (TDD). USDA is an equal opportunity provider and employer.

Cover: Typical area of Caples silty clay loam, 0 to 3 percent slopes, used for alfalfa hay.

http://www.nrcs.usda.gov

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Contents

How To Use This Soil Survey ................................. 3Contents .................................................................. 5Foreword ............................................................... 13General Nature of the County ................................. 16

History and Development ................................... 16Physiography, Relief, and Drainage .................... 16Climate ............................................................... 16

How This Survey Was Made ................................... 17General Soil Map Units ........................................ 19

Soils Dominantly on Flood Plains andTerraces ..................................................... 19

1. Caples-Clato-Newberg ............................... 192. Kelso-Kalama-Minniece ............................. 193. Riverwash-Cowlitz-Delameter .................... 20Soils Dominantly on Warm Terraces and

Uplands ...................................................... 224. Loper-Bunker ............................................. 225. Zenker-Lytell .............................................. 226. Centralia-Buckpeak .................................... 227. Germany-Raught ....................................... 238. Hazeldell-Olympic ...................................... 239. Seaquest-Sara ........................................... 23

10. Baumgard-Schneider ................................. 2411. Gobar-Mulholland ...................................... 2412. Cinebar-Newaukum-Siouxon ..................... 2413. Yalelake-Zymer .......................................... 25Soils Dominantly on Cool Terraces and

Uplands ...................................................... 2514. Lates-Murnen ............................................ 2515. Pheeney-Beigle ......................................... 2516. Hoffstadt-Domell ........................................ 2617. Studebaker-Forsyth-Lithic Umbric

Vitrandepts ................................................. 2618. Swift-Cinnamon ......................................... 26Soils Dominantly on Cold Terraces and

Uplands ...................................................... 2719. Stahl-Reichel ............................................. 2720. Vanson-Hatchet-Lonestar .......................... 2721. Polepatch-Andic Cryumbrepts ................... 27

Detailed Soil Map Units ........................................ 291—Andaquepts, 0 to 3 percent slopes ................ 302—Andic Cryaquepts-Rock outcrop complex,

50 to 90 percent slopes ................................ 303—Andic Cryumbrepts-Rock outcrop complex,

50 to 90 percent slopes ................................ 31

4—Andic Cryumbrepts, overblown-Rockoutcrop complex, 50 to 90 percent slopes .... 32

5—Arents, 0 to 5 percent slopes ........................ 336—Astoria silt loam, 5 to 30 percent slopes ....... 337—Baumgard silt loam, 5 to 30 percent

slopes .......................................................... 348—Baumgard silt loam, 30 to 65 percent

slopes .......................................................... 359—Beigle silt loam, 5 to 30 percent slopes ......... 3610—Beigle silt loam, 30 to 65 percent slopes ..... 3711—Boistfort silt loam, 5 to 30 percent slopes.... 3812—Buckpeak silt loam, 30 to 65 percent

slopes .......................................................... 3913—Buckpeak silt loam, 65 to 90 percent

slopes .......................................................... 4014—Bunker silt loam, 5 to 30 percent slopes ..... 4115—Bunker silt loam, 30 to 65 percent

slopes .......................................................... 4216—Camas cobbly loam, 0 to 3 percent

slopes .......................................................... 4317—Caples silty clay loam, 0 to 3 percent

slopes .......................................................... 4418—Carrolls sand, flooded, 0 to 2 percent

slopes .......................................................... 4519—Carrolls loamy sand, 0 to 2 percent

slopes .......................................................... 4620—Carrolls fine sandy loam, overwash,

0 to 1 percent slopes.................................... 4621—Centralia silt loam, 0 to 8 percent slopes .... 4722—Centralia silt loam, 8 to 20 percent

slopes .......................................................... 4823—Centralia silt loam, 20 to 30 percent

slopes .......................................................... 5024—Cinebar loamy sand, overblown, 5 to 30

percent slopes ............................................. 5125—Cinebar silt loam, 0 to 5 percent slopes ...... 5126—Cinebar silt loam, 5 to 20 percent slopes .... 5327—Cinebar silt loam, 20 to 30 percent

slopes .......................................................... 5428—Cinebar silt loam, 30 to 65 percent

slopes .......................................................... 5529—Cinnamon sandy loam, 5 to 30 percent

slopes .......................................................... 5630—Cinnamon sandy loam, 30 to 65 percent

slopes .......................................................... 57

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31—Cinnamon sandy loam, 65 to 90 percentslopes .......................................................... 58

32—Clato silt loam, 0 to 3 percent slopes .......... 5933—Coweeman silt loam, 5 to 15 percent

slopes .......................................................... 6034—Coweeman silty clay loam, 3 to 30

percent slopes ............................................. 6235—Cowlitz very gravelly sand, 0 to 1 percent

slopes .......................................................... 6336—Cowlitz extremely gravelly sand,

disturbed, 0 to 5 percent slopes ................... 6337—Cowlitz extremely gravelly sand,

disturbed, 5 to 15 percent slopes ................. 6438—Cowlitz extremely gravelly sand,

disturbed, 15 to 30 percent slopes ............... 6439—Delameter extremely gravelly loamy

sand, 0 to 20 percent slopes ........................ 6440—Dobbs gravelly silt loam, 5 to 30 percent

slopes .......................................................... 6541—Dobbs gravelly silt loam, 30 to 65

percent slopes ............................................. 6642—Domell loamy sand, overblown, 5 to 30

percent slopes ............................................. 6743—Domell sandy loam, 5 to 30 percent

slopes .......................................................... 6844—Domell sandy loam, 30 to 70 percent

slopes .......................................................... 6945—Domell stony sandy loam, 5 to 30

percent slopes ............................................. 7046—Domell stony sandy loam, 30 to 65

percent slopes ............................................. 7147—Edgewick silt loam, 0 to 3 percent slopes ... 7248—Elkprairie loamy sand, 0 to 30 percent

slopes .......................................................... 7349—Elochoman silt loam, 5 to 30 percent

slopes .......................................................... 7450—Ferteg silt loam, 0 to 8 percent slopes ........ 7451—Ferteg silt loam, 8 to 30 percent slopes ...... 7552—Forsyth very cobbly loamy sand, 0 to 30

percent slopes ............................................. 7653—Forsyth very cobbly loamy sand,

50 to 90 percent slopes ................................ 7754—Germany silt loam, 0 to 8 percent

slopes .......................................................... 78

55—Germany silt loam, 8 to 20 percentslopes .......................................................... 80



58—Germany silt loam, tuff substratum,8 to 20 percent slopes.................................. 83

59—Germany silt loam, tuff substratum,20 to 30 percent slopes ................................ 84

60—Germany silt loam, tuff substratum,30 to 65 percent slopes ................................ 85

61—Gobar silt loam, 5 to 30 percent slopes ....... 8662—Gobar silt loam, 30 to 65 percent slopes ..... 8763—Gobar silt loam, 65 to 90 percent slopes ..... 8864—Gobar silt loam, 5 to 45 percent slopes,

dissected ..................................................... 8965—Godfrey silt loam, 0 to 3 percent slopes ...... 9066—Greenwater loamy sand, 8 to 45 percent

slopes .......................................................... 9167—Greenwater loamy sand, overblown,

0 to 8 percent slopes.................................... 9268—Greenwater gravelly loamy sand, 0 to 8

percent slopes ............................................. 9369—Greenwater fine sandy loam, 0 to 8

percent slopes ............................................. 9470—Hatchet loamy sand, overblown, 30 to 65

percent slopes ............................................. 9571—Hatchet loamy sand, overblown, 65 to 90

percent slopes ............................................. 9672—Hatchet very cobbly sandy loam,

30 to 65 percent slopes ................................ 9773—Hatchet-Rock outcrop complex, 30 to 65

percent slopes ............................................. 9874—Hatchet-Rock outcrop complex, 65 to 90

percent slopes ............................................. 9975—Hatchet, overblown-Rock outcrop

complex, 65 to 90 percent slopes .............. 10076—Hazeldell gravelly silt loam, 8 to 20

percent slopes ........................................... 10177—Hazeldell gravelly silt loam, 20 to 30

percent slopes ........................................... 10278—Hazeldell gravelly silt loam, 30 to 65

percent slopes ........................................... 103

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79—Hazeldell gravelly silt loam, tuffsubstratum, 5 to 30 percent slopes ............ 104

80—Hazeldell gravelly silt loam, tuffsubstratum, 30 to 65 percent slopes .......... 105

81—Histic Cryaquepts, 0 to 1 percentslopes ........................................................ 106

82—Histic Humaquepts, 0 to 3 percentslopes ........................................................ 107

83—Hoffstadt loamy sand, overblown,5 to 30 percent slopes................................ 107

84—Hoffstadt loamy sand, overblown,30 to 70 percent slopes .............................. 108

85—Hoffstadt very gravelly sandy loam,5 to 30 percent slopes................................ 109

86—Hoffstadt very gravelly sandy loam,30 to 65 percent slopes .............................. 110

87—Hoffstadt-Rock outcrop complex,30 to 65 percent slopes .............................. 111

88—Hoffstadt-Rock outcrop complex,65 to 90 percent slopes .............................. 112

89—Hoffstadt, overblown-Rock outcropcomplex, 30 to 65 percent slopes .............. 113

90—Hoffstadt, overblown-Rock outcropcomplex, 65 to 90 percent slopes .............. 114

91—Jonas silt loam, 5 to 30 percent slopes ..... 11692—Jonas silt loam, 30 to 65 percent slopes ... 11793—Kalama gravelly loam, 8 to 15 percent

slopes ........................................................ 11894—Kalama gravelly loam, 15 to 30 percent

slopes ........................................................ 11995—Kalama gravelly loam, 30 to 60 percent

slopes ........................................................ 12096—Katula very cobbly loam, 30 to 65

percent slopes ........................................... 12197—Katula very cobbly loam, 65 to 90

percent slopes ........................................... 12298—Katula-Bunker complex, 30 to 65

percent slopes ........................................... 12399—Katula-Bunker complex, 65 to 90

percent slopes ........................................... 124100—Kelso silt loam, 0 to 8 percent slopes ...... 125101—Kelso silt loam, 8 to 15 percent slopes .... 126102—Kelso silt loam, 15 to 30 percent

slopes ........................................................ 127

103—Kelso silt loam, 30 to 50 percentslopes ........................................................ 129

104—Kosmos silt loam, 0 to 3 percentslopes ........................................................ 129

105—Lacamas silt loam, 0 to 6 percentslopes ........................................................ 130

106—Lates silt loam, 5 to 30 percent slopes .... 131107—Lates silt loam, 30 to 65 percent

slopes ........................................................ 132108—Lates-Rock outcrop complex, 65 to 90

percent slopes ........................................... 133109—Lithic Haplumbrepts, 50 to 100 percent

slopes ........................................................ 134110—Lithic Umbric Vitrandepts, 0 to 15

percent slopes ........................................... 135111—Lonestar sand, 30 to 65 percent

slopes ........................................................ 136112—Lonestar loamy sand, overblown,

5 to 30 percent slopes................................ 137113—Lonestar loamy sand, overblown,

30 to 65 percent slopes .............................. 137114—Lonestar loamy sand, overblown,

65 to 90 percent slopes .............................. 138115—Lonestar sandy loam, 5 to 30 percent

slopes ........................................................ 139116—Lonestar sandy loam, 30 to 65 percent

slopes ........................................................ 140117—Lonestar sandy loam, 65 to 90 percent

slopes ........................................................ 141118—Lonestar sandy loam, tuff substratum,

5 to 30 percent slopes................................ 142119—Loper silt loam, 20 to 30 percent

slopes ........................................................ 143120—Loper silt loam, 30 to 65 percent

slopes ........................................................ 144121—Lytell silt loam, 5 to 30 percent slopes .... 145122—Lytell silt loam, 30 to 75 percent

slopes ........................................................ 146123—Mart silt loam, 0 to 8 percent slopes ....... 147124—Mart silt loam, 8 to 20 percent slopes ..... 148125—Mart silt loam, 20 to 30 percent slopes ... 149126—Mart silt loam, 30 to 65 percent slopes ... 150127—Maytown silt loam, 0 to 3 percent

slopes ........................................................ 151

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128—Melbourne loam, 8 to 20 percentslopes ........................................................ 153

129—Melbourne loam, 20 to 30 percentslopes ........................................................ 155

130—Minniece silt loam, 0 to 8 percentslopes ........................................................ 156

131—Mountsolo gravelly sand, 0 to 1percent slopes ........................................... 157

132—Mulholland silt loam, 5 to 30 percentslopes ........................................................ 157

133—Murnen silt loam, 5 to 30 percentslopes ........................................................ 158

134—Natal silty clay loam, 0 to 4 percentslopes ........................................................ 159

135—Newaukum gravelly silt loam, tuffsubstratum, 8 to 30 percent slopes ............ 160

136—Newaukum gravelly silt loam, tuffsubstratum, 30 to 65 percent slopes .......... 161

137—Newaukum cobbly silt loam, 5 to 30percent slopes ........................................... 162



140—Newaukum-Rock outcrop complex,15 to 65 percent slopes .............................. 165

141—Newberg fine sandy loam, 0 to 3percent slopes ........................................... 166

142—Olequa silt loam, 0 to 8 percent slopes ... 168143—Olequa silt loam, 8 to 20 percent

slopes ........................................................ 169144—Olequa silt loam, 20 to 30 percent

slopes ........................................................ 171145—Olequa silt loam, 30 to 65 percent

slopes ........................................................ 172146—Olympic silt loam, 2 to 8 percent




slopes ........................................................ 177150—Olympic silt loam, tuff substratum,

5 to 30 percent slopes................................ 178

151—Panamaker gravelly sand, 0 to 3percent slopes ........................................... 179

152—Panamaker gravelly sand, flooded,0 to 1 percent slopes.................................. 179

153—Pheeney gravelly silt loam, 5 to 30percent slopes ........................................... 180



156—Pheeney-Beigle complex, 5 to 30percent slopes ........................................... 183

157—Pheeney-Beigle complex, 30 to 65percent slopes ........................................... 184

158—Pheeney-Rock outcrop complex,30 to 65 percent slopes .............................. 185

159—Pheeney-Rock outcrop complex,65 to 90 percent slopes .............................. 186

160—Pilchuck loamy fine sand, 0 to 8percent slopes ........................................... 187

161—Pits ......................................................... 189162—Polepatch loamy sand, overblown,

0 to 30 percent slopes................................ 189163—Polepatch very cobbly loamy sand,

0 to 30 percent slopes................................ 190164—Polepatch very cobbly loamy sand,

50 to 90 percent slopes .............................. 191165—Polepatch extremely bouldery loamy

sand, 0 to 30 percent slopes ...................... 192166—Prather silty clay loam, 0 to 5 percent

slopes ........................................................ 192167—Prather silty clay loam, 5 to 15 percent

slopes ........................................................ 194168—Raught silt loam, 20 to 30 percent



slopes ........................................................ 197171—Reichel silt loam, 5 to 30 percent

slopes ........................................................ 198172—Riverwash ............................................... 198173—Rock outcrop-Rubble land complex ........ 199174—Rose Valley silt loam, 0 to 8 percent

slopes ........................................................ 199

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175—Rose Valley silt loam, 8 to 15 percentslopes ........................................................ 200

176—Salkum silt loam, 2 to 8 percent slopes ... 202177—Salkum silt loam, 8 to 20 percent

slopes ........................................................ 203178—Salkum silt loam, 20 to 30 percent

slopes ........................................................ 204179—Sara silt loam, 0 to 8 percent slopes ....... 205180—Sara silt loam, 8 to 15 percent slopes ..... 206181—Sara silt loam, 15 to 40 percent slopes ... 207182—Sara silty clay loam, 0 to 8 percent

slopes ........................................................ 208183—Sarazan very gravelly silt loam, 5 to 30

percent slopes ........................................... 209184—Sarazan very gravelly silt loam,

30 to 65 percent slopes .............................. 210185—Sauvola loam, 0 to 8 percent slopes ....... 211186—Sauvola loam, 8 to 15 percent slopes ..... 212187—Sauvola loam, 15 to 30 percent slopes ... 214188—Schneider very gravelly loam, 5 to 30

percent slopes ........................................... 215189—Schneider very gravelly loam, 30 to 65

percent slopes ........................................... 216190—Schneider-Rock outcrop complex,

15 to 65 percent slopes .............................. 217191—Schneider-Rock outcrop complex,

65 to 90 percent slopes .............................. 218192—Seaquest silt loam, 0 to 8 percent

slopes ........................................................ 219193—Seaquest silt loam, 8 to 20 percent

slopes ........................................................ 220194—Seaquest silt loam, 20 to 30 percent

slopes ........................................................ 222195—Semiahmoo muck, 0 to 1 percent

slopes ........................................................ 223196—Siouxon very cobbly silt loam, 5 to 30

percent slopes ........................................... 223197—Siouxon very cobbly silt loam, 30 to 65

percent slopes ........................................... 224198—Siouxon-Rock outcrop complex,

65 to 90 percent slopes .............................. 225199—Snohomish silty clay loam, 0 to 1

percent slopes ........................................... 226200—Solo gravelly loamy sand, 0 to 8

percent slopes ........................................... 227

201—Speelyai gravelly loamy sand, 0 to 8percent slopes ........................................... 228

202—Speelyai gravelly loamy sand, 15 to 60percent slopes ........................................... 229

203—Spodic Cryopsamments, 0 to 30percent slopes ........................................... 230

204—Stahl very gravelly silt loam, 30 to 65percent slopes ........................................... 231

205—Stahl-Reichel complex, 5 to 30 percentslopes ........................................................ 232

206—Stahl-Reichel complex, 30 to 65percent slopes ........................................... 233

207—Stahl-Rock outcrop complex, 30 to 75percent slopes ........................................... 234

208—Stella silt loam, 3 to 8 percent slopes ...... 235209—Stella silt loam, 8 to 15 percent

slopes ........................................................ 237210—Stella silt loam, 15 to 30 percent

slopes ........................................................ 238211—Studebaker very gravelly loamy sand,

0 to 20 percent slopes................................ 239212—Swem cobbly silt loam, 5 to 30 percent

slopes ........................................................ 239213—Swem cobbly silt loam, 30 to 65

percent slopes ........................................... 240214—Swift loamy sand, overblown, 30 to 65

percent slopes ........................................... 241215—Swift loamy sand, overblown, 65 to 90

percent slopes ........................................... 242216—Swift sandy loam, 5 to 30 percent

slopes ........................................................ 243217—Swift sandy loam, 30 to 65 percent

slopes ........................................................ 244218—Swift sandy loam, 65 to 90 percent

slopes ........................................................ 245219—Swift-Rock outcrop complex, 30 to 65

percent slopes ........................................... 246220—Swift-Rock outcrop complex, 65 to 90

percent slopes ........................................... 247221—Swift, overblown-Rock outcrop

complex, 40 to 90 percent slopes .............. 248222—Vader loam, 5 to 30 percent slopes ......... 250223—Vader loam, 30 to 65 percent slopes ....... 250224—Vanson loamy sand, overblown,

5 to 30 percent slopes................................ 251

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225—Vanson loamy sand, overblown,30 to 65 percent slopes .............................. 252

226—Vanson loamy sand, overblown,65 to 90 percent slopes .............................. 253

227—Vanson loamy sand, till substratum,overblown, 5 to 30 percent slopes .............. 254

228—Vanson loamy sand, till substratum,overblown, 30 to 65 percent slopes ............ 255

229—Vanson sandy loam, 5 to 30 percentslopes ........................................................ 257



232—Vanson sandy loam, tuff substratum,5 to 30 percent slopes................................ 260

233—Vanson sandy loam, tuff substratum,30 to 65 percent slopes .............................. 261

234—Vanson cobbly sandy loam, tillsubstratum, 5 to 30 percent slopes ............ 262

235—Vanson cobbly sandy loam, tillsubstratum, 30 to 65 percent slopes .......... 263

236—Vanson-Hatchet loamy sands,overblown, 5 to 30 percent slopes .............. 264

237—Vanson-Hatchet loamy sands,overblown, 30 to 65 percent slopes ............ 265

238—Vanson-Hatchet loamy sands,overblown, 65 to 90 percent slopes ............ 266

239—Vanson-Hatchet complex, 5 to 30percent slopes ........................................... 267



242—Vanson-Rock outcrop complex,30 to 65 percent slopes .............................. 270

243—Vanson-Rock outcrop complex,65 to 90 percent slopes .............................. 272

244—Vanson, overblown-Rock outcropcomplex, 30 to 65 percent slopes .............. 273

245—Vanson, overblown-Rock outcropcomplex, 65 to 90 percent slopes .............. 274

246—Voight silt loam, 5 to 30 percent slopes ... 275247—Winston silt loam, 0 to 8 percent

slopes ........................................................ 276

248—Wyant loam, 5 to 30 percent slopes ........ 277249—Wyant loam, 30 to 65 percent slopes ...... 278250—Xana loamy sand, 5 to 30 percent

slopes ........................................................ 279251—Xana loamy sand, 30 to 65 percent

slopes ........................................................ 279252—Xeno silt loam, 5 to 30 percent

slopes ........................................................ 280253—Xeno silt loam, 30 to 65 percent

slopes ........................................................ 281254—Xerorthents, 50 to 90 percent slopes ...... 282255—Yalelake sandy loam, 5 to 30 percent

slopes ........................................................ 283256—Yalelake sandy loam, 30 to 65 percent

slopes ........................................................ 284257—Yalelake sandy loam, 65 to 90 percent

slopes ........................................................ 285258—Zenker silt loam, 30 to 65 percent

slopes ........................................................ 286259—Zenker silt loam, 65 to 90 percent

slopes ........................................................ 287260—Zymer sandy loam, 30 to 65 percent

slopes ........................................................ 288261—Zymer-Rock outcrop complex, 65 to 90

percent slopes ........................................... 289262—Zynbar silt loam, 5 to 30 percent

slopes ........................................................ 290Use and Management of the Soils .................... 293

Crops and Pasture ........................................... 293Yields per Acre ............................................. 294Land Capability Classification ...................... 295Prime Farmland ........................................... 296

Woodland ......................................................... 297Woodland Zones .......................................... 297Woodland Management and

Productivity .......................................... 300Recreation ........................................................ 303Wildlife Habitat ................................................. 304Engineering ...................................................... 305

Building Site Development ........................... 306Sanitary Facilities ......................................... 307Construction Materials ................................. 308Water Management ...................................... 309

Soil Properties .................................................... 311Engineering Index Properties ........................... 311

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Physical Properties .......................................... 312Chemical Properties ......................................... 313Soil and Water Features ................................... 314

Classification of the Soils .................................. 317Soil Series and Their Morphology ......................... 317

Astoria Series ................................................... 317Baumgard Series ............................................. 318Beigle Series .................................................... 319Boistfort Series ................................................. 319Buckpeak Series .............................................. 320Bunker Series ................................................... 321Camas Series .................................................. 321Caples Series ................................................... 322Carrolls Series.................................................. 323Centralia Series ................................................ 323Cinebar Series ................................................. 324Cinnamon Series .............................................. 325Clato Series...................................................... 325Coweeman Series ............................................ 326Cowlitz Series .................................................. 327Delameter Series ............................................. 327Dobbs Series .................................................... 328Domell Series ................................................... 328Edgewick Series ............................................... 329Elkprairie Series ............................................... 330Elochoman Series ............................................ 331Ferteg Series ................................................... 331Forsyth Series .................................................. 332Germany Series ............................................... 333Gobar Series .................................................... 333Godfrey Series ................................................. 334Greenwater Series ........................................... 335Hatchet Series.................................................. 335Hazeldell Series ............................................... 336Hoffstadt Series ................................................ 337Jonas Series .................................................... 338Kalama Series .................................................. 338Katula Series .................................................... 339Kelso Series ..................................................... 340Kosmos Series ................................................. 341Lacamas Series ............................................... 341Lates Series ..................................................... 342Lonestar Series ................................................ 343Loper Series ..................................................... 344Lytell Series ...................................................... 345

Mart Series....................................................... 345Maytown Series ................................................ 346Melbourne Series ............................................. 347Minniece Series ................................................ 347Mountsolo Series ............................................. 348Mulholland Series ............................................. 349Murnen Series .................................................. 349Natal Series...................................................... 350Newaukum Series ............................................ 351Newberg Series ................................................ 351Olequa Series .................................................. 352Olympic Series ................................................. 353Panamaker Series ............................................ 353Pheeney Series ................................................ 354Pilchuck Series ................................................. 354Polepatch Series .............................................. 355Prather Series .................................................. 356Raught Series .................................................. 356Reichel Series .................................................. 357Rose Valley Series ........................................... 357Salkum Series .................................................. 358Sara Series ...................................................... 359Sarazan Series ................................................. 360Sauvola Series ................................................. 360Schneider Series .............................................. 361Seaquest Series ............................................... 362Semiahmoo Series ........................................... 363Siouxon Series ................................................. 363Snohomish Series ............................................ 364Solo Series ....................................................... 365Speelyai Series ................................................ 366Stahl Series ...................................................... 366Stella Series ..................................................... 367Studebaker Series ............................................ 368Swem Series .................................................... 368Swift Series ...................................................... 369Vader Series ..................................................... 370Vanson Series .................................................. 370Voight Series .................................................... 371Winston Series ................................................. 372Wyant Series .................................................... 373Xana Series...................................................... 374Xeno Series...................................................... 374Yalelake Series ................................................. 375Zenker Series ................................................... 376

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Issued 2006

Zymer Series .................................................... 377Zynbar Series ................................................... 378

Formation of the Soils ........................................ 379Parent Material ................................................. 379Climate ............................................................. 380Living Organisms ............................................. 381Topography....................................................... 382Time ................................................................. 383

References .......................................................... 385Glossary .............................................................. 387Tables .................................................................. 399

Table 1.—Temperature and Precipitation .......... 400Table 2.—Freeze Dates in Spring and Fall ........ 402Table 3.—Growing Season ............................... 403Table 4.—Acreage and Proportionate Extent

of the Soils ................................................. 404Table 5.—Land Capability and Yields per

Acre of Nonirrigated Crops and Pasture .... 409

Table 6.—Woodland Management andProductivity ................................................ 423

Table 7.—Woodland Productivity ...................... 452Table 8.—Selected Management Concerns

on Woodland .............................................. 460Table 9.—Woodland Road Construction ........... 472Table 10.—Recreational Development .............. 483Table 11.—Wildlife Habitat ................................ 507Table 12.—Building Site Development .............. 527Table 13.—Sanitary Facilities ........................... 553Table 14.—Construction Materials .................... 579Table 15.—Water Management ........................ 605Table 16.—Engineering Index Properties ......... 638Table 17.—Physical Properties of the Soils ...... 699Table 18.—Chemical Properties of the Soils ..... 725Table 19.—Water Features ............................... 752Table 20.—Soil Features .................................. 766Table 21.—Classification of the Soils ................ 781

13

This soil survey contains information that affects land use planning in this surveyarea. It contains predictions of soil behavior for selected land uses. The survey alsohighlights soil limitations, improvements needed to overcome the limitations, and theimpact of selected land uses on the environment.

This soil survey is designed for many different users. Farmers, ranchers, foresters,and agronomists can use it to evaluate the potential of the soil and the managementneeded for maximum food and fiber production. Planners, community officials,engineers, developers, builders, and home buyers can use the survey to plan land use,select sites for construction, and identify special practices needed to ensure properperformance. Conservationists, teachers, students, and specialists in recreation, wildlifemanagement, waste disposal, and pollution control can use the survey to help themunderstand, protect, and enhance the environment.

Various land use regulations of Federal, State, and local governments may imposespecial restrictions on land use or land treatment. The information in this report isintended to identify soil properties that are used in making various land use or landtreatment decisions. Statements made in this report are intended to help the land usersidentify and reduce the effects of soil limitations on various land uses. The landowner oruser is responsible for identifying and complying with existing laws and regulations.

Great differences in soil properties can occur within short distances. Some soils areseasonally wet or subject to flooding. Some are shallow to bedrock. Some are toounstable to be used as a foundation for buildings or roads. Clayey or wet soils arepoorly suited to use as septic tank absorption fields. A high water table makes a soilpoorly suited to basements or underground installations.

These and many other soil properties that affect land use are described in this soilsurvey. Broad areas of soils are shown on the general soil map. The location of eachsoil is shown on the detailed soil maps. Each soil in the survey area is described.Information on specific uses is given for each soil. Help in using this publication andadditional information are available at the local office of the Natural ResourcesConservation Service or the Cooperative Extension Service.

Raymond L. HughbanksState ConservationistNatural Resources Conservation Service

Foreword

14

Location of Cowlitz County in Washington.

Olympia

15

By Dave Guenther, district conservationist, Natural ResourcesConservation Service.

COWLITZ COUNTY is in the southwestern part ofWashington. It has a total area of about 1,139 squaremiles, or 738,071 acres. The population of the countyin 1998 was 93,100. Kelso, the county seat, had apopulation of 11,950. It is located at the center of thesouthwestern boundary of the county. Longview andKalama, which are along the Columbia River,accommodate oceangoing freight vessels and aremajor shipping ports for forest and agriculturalproducts.

The county is bounded on the west by WahkiakumCounty, on the southwest by the Columbia River, onthe south by the Lewis River, on the east by SkamaniaCounty, and on the north by Lewis County. The countyextends 2 to 48 miles from west to east and 14 to 48miles from north to south.

The foothills of the Cascade Range form the ruggedterrain of the eastern one-third of the county. Tributaryrivers and streams converge with the Cowlitz River toform relatively flat alluvial bottom land that makes upthe Cowlitz River valley in the central one-third of thecounty. The western one-third of the county isdominantly rugged foothills of the Coast Range.Generally, the streams in this part of the county drain

to the south directly into the Columbia River. TheColumbia River and its tributaries are influenced bythe tides of the Pacific Ocean.

Timber harvesting and forest productsmanufacturing are the major resource-basedenterprises in the county. Significant agriculturalenterprises include production of forage for livestockand production of cane berries and flower bulbs.

Soil scientists have identified more than 90 differenttypes of soils in the county. The soils along the majorstreams are suited to agricultural crop production. Inmost of these areas, dikes have been constructed toprotect the soils from flooding. For maximum cropproduction, extensive drainage systems have beeninstalled to control the water table. The potentialproductivity of the forested upland soils is one of thehighest in the world.

This survey updates the soil survey of CowlitzArea, Washington (USDA 1974), the soil survey ofSt. Helens Tree Farm (Duncan and Steinbrenner1971), and the unpublished soil survey of RyderwoodTree Farm. This survey provides additionalinformation and has larger maps, which show thesoils in greater detail. It includes a large area of soilson private industrial woodland that previously wasunmapped, and it includes changes that occurred as

Soil Survey of

Cowlitz County, WashingtonBy Russell F. Pringle, Natural Resources Conservation Service, and Robert L. Evans,Washington State Department of Natural Resources

Fieldwork by Robert L. Evans, Jeffrey A. Sherwood, Phillip Schoeneburger, RonaldKurtz, and Robert Puls, Washington State Department of Natural Resources, andRussell F. Pringle, Terry L. Aho, and Jay T. Kehne, Natural Resources ConservationService

Woodland fieldwork by Gregory S. Fisher, Natural Resources Conservation Service,and George Carnine and Roger Stark, Washington State Department of NaturalResources

United States Department of Agriculture, Natural Resources Conservation Service,in cooperation withWashington State Department of Natural Resources and Washington State UniversityAgricultural Research Center

16 Soil Survey of

a result of the eruptions of Mount St. Helens in 1980and 1982.

General Nature of the CountyThis section gives general information about the

history and development; physiography, relief, anddrainage; and climate of the county.

History and Development

The county has served as home and huntinggrounds for many different people for centuries. At thetime European settlers arrived, the Cowlitz Indianslived throughout the area. Their communal lifestyle,which was based on use of the natural resources inthe county, was disrupted as European interestincreased. In 1775 Spanish Conquistadors claimed thearea. In 1805 Lewis and Clark stated in their journalsthat the area attracted fur trappers, traders, andsettlers. The Hudson’s Bay Company had a tradingpost in the area when the first European settlersarrived in 1849. Monticello became the first countyseat in 1853, but the village was later abandoned.

Forest products manufacturing and shipping havebeen the major industries in the county for 150 years.Today the area is a gateway to a variety of recreationareas as well as an important transportation hub alongthe Lower Columbia River.

Physiography, Relief, and Drainage

The county can be divided into four distinctphysiographic areas—the Cascade Range foothills,Lower Cowlitz Basin, Lower Columbia Basin, andCoast Range foothills. The Cascade Rangefoothills are steep-sided ridges that generally runwest-northwest from the west slopes of theMount St. Helens Volcano, the summit of which is inSkamania County. Elevation of these foothills rangesfrom about 1,200 feet above sea level near Toutle toabout 4,600 feet on the ridgetops. The major streamsthat drain this area include the North Fork and SouthFork of the Toutle River and the Green, Coweeman,Kalama, and Lewis Rivers.

The Lower Cowlitz Basin consists of alluvial valleybottoms, and it serves as the flood plain for many ofthe drainageways in the foothills of the Cascade andCoast Ranges. Elevation of the Lower Cowlitz Basinranges from about 20 feet above sea level on the floodplain at the mouth of the Cowlitz River, near Kelso, toabout 30 feet above sea level 22 miles upstream, nearOlequa Crossing. From the confluence of the ToutleRiver downstream to its juncture with the Columbia

River, spoil from the eruption of Mount St. Helens in1980 has been dredged from the Cowlitz River anddeposited along its banks. The spoil acts as a dike thattends to keep the river from flowing onto the floodplain during periods of high flow. Flooding would stillbe a common occurrence, however, except for thethree large artificial reservoirs on the upper part of theCowlitz River. The rivers affected by the mudflow andother debris from Mount St. Helens continue to inciseand transport large quantities of bedload. This bedloadperiodically is dredged to keep the Columbia Rivershipping channels open downstream and is depositedalong the Cowlitz River.

The Lower Columbia Basin consists of relatively flatterrain on islands in the Columbia River and alluvialdeltas at the mouth of the Lewis and Cowlitz Rivers.Willow Grove Island, parts of Longview, and bottomland at the mouth of the Lewis River have been dikedor drained for urban, industrial, and agricultural uses.These areas otherwise would be subject to frequentperiods of flooding from storm-water runoff or oceantides, or both.

The Coast Range foothills drain to the south intothe Columbia River. Elevation ranges from about20 feet above sea level on the narrow valley floor toabout 2,600 feet on the ridgetops.

Climate

The climate of the county is tempered by the windfrom the Pacific Ocean. Summers are fairly warm, buthot days are rare. Winters are cool, but snow andfreezing temperatures are uncommon, except at thehigher elevations. In summer, rainfall is extremelylight. Precipitation commonly is absent for severalweeks. Crops that are actively growing in summerneed to be irrigated. Periods of rainfall are frequentduring the rest of the year, especially late in fall andin winter.

Table 1 gives data on temperature and precipitationfor the survey area as recorded at Cougar andLongview, Washington, in the period 1951 to 1981.Table 2 shows probable dates of the first freeze in falland the last freeze in spring. Table 3 provides data onlength of the growing season.

In winter, the average temperature is 38 degrees Fat Cougar and 41 degrees at Longview and theaverage daily minimum temperature is 33 degrees atCougar and 34 degrees at Longview. The lowesttemperature on record, which occurred on December30, 1968, at Cougar and on December 9, 1972, atLongview, is 4 degrees. In summer, the averagetemperature at Cougar and Longview is 63 degreesand the average daily maximum temperature is

Cowlitz County, Washington 17

75 degrees. The highest recorded temperature, whichoccurred on August 10, 1981, at Longview, is 108degrees.

Growing degree days are shown in table 1. Theyare equivalent to “heat units.” During the month,growing degree days accumulate by the amount thatthe average temperature each day exceeds a basetemperature (40 degrees). The normal monthlyaccumulation is used to schedule single or successiveplantings of a crop between the last freeze in springand the first freeze in fall.

The total annual precipitation is about 116 inches atCougar and 46 inches at Longview. Of this, 25 percentusually falls in April through September. The growingseason for most crops falls within this period. Theheaviest 1-day rainfall during the period of record was5.54 inches at Cougar on November 20, 1962.Thunderstorms occur on about 5 days each year, andmost occur in summer.

The average seasonal snowfall is about 28 inchesat Cougar and 6 inches at Longview. The greatestsnow depth at any one time during the period ofrecord was 58 inches at Cougar and 18 inches atLongview. On the average, 10 days at Cougar and3 days at Longview have at least 1 inch of snow on theground. The number of such days varies greatly fromyear to year.

The average relative humidity in midafternoon isabout 80 percent. Humidity is higher at night, and theaverage at dawn is about 90 percent. The sun shines60 percent of the time possible in summer and30 percent in winter. The prevailing wind is from thesouth-southwest. Average windspeed is highest,7 miles per hour, in spring.

In most winters, one or two storms over the wholearea bring strong winds that are sometimes damaging.In some years the accompanying heavy rain results inserious flooding. Every few years a continentalairmass from the east results in abnormaltemperatures. If this occurs in winter, severalconsecutive days are well below freezing. If it occurs insummer, a week or longer is sweltering.

How This Survey Was MadeThis survey was made to provide information about

the soils and miscellaneous areas in the survey area.The information includes a description of the soils andmiscellaneous areas and their location and adiscussion of their suitability, limitations, andmanagement for specified uses. Soil scientistsobserved the steepness, length, and shape of theslopes; the general pattern of drainage; the kinds ofcrops and native plants; and the kinds of bedrock.

They dug many holes to study the soil profile, which isthe sequence of natural layers, or horizons, in a soil.The profile extends from the surface down into theunconsolidated material in which the soil formed. Theunconsolidated material is devoid of roots and otherliving organisms and has not been changed by otherbiological activity.

The soils and miscellaneous areas in the surveyarea are in an orderly pattern that is related to thegeology, landforms, relief, climate, and naturalvegetation of the area. Each kind of soil andmiscellaneous area is associated with a particular kindof landform or with a segment of the landform. Byobserving the soils and miscellaneous areas in thesurvey area and relating their position to specificsegments of the landform, a soil scientist develops aconcept or model of how they were formed. Thus,during mapping, this model enables the soil scientistto predict with a considerable degree of accuracy thekind of soil or miscellaneous area at a specific locationon the landscape.

Commonly, individual soils on the landscape mergeinto one another as their characteristics graduallychange. To construct an accurate soil map, however,soil scientists must determine the boundariesbetween the soils. They can observe only a limitednumber of soil profiles. Nevertheless, theseobservations, supplemented by an understanding ofthe soil-vegetation-landscape relationship, aresufficient to verify predictions of the kinds of soil in anarea and to determine the boundaries.

Soil scientists recorded the characteristics of thesoil profiles that they studied. They noted soil color,texture, size and shape of soil aggregates, kind andamount of rock fragments, distribution of plant roots,reaction, and other features that enable them toidentify soils. After describing the soils in the surveyarea and determining their properties, the soilscientists assigned the soils to taxonomic classes(units). Taxonomic classes are concepts. Eachtaxonomic class has a set of soil characteristics withprecisely defined limits. The classes are used as abasis for comparison to classify soils systematically.Soil taxonomy, the system of taxonomicclassification used in the United States, is basedmainly on the kind and character of soil propertiesand the arrangement of horizons within the profile.After the soil scientists classified and named thesoils in the survey area, they compared the individualsoils with similar soils in the same taxonomic class inother areas so that they could confirm data andassemble additional data based on experience andresearch.

While a soil survey is in progress, samples of some

18

of the soils in the area generally are collected forlaboratory analyses and for engineering tests. Soilscientists interpret the data from these analyses andtests as well as the field-observed characteristics andthe soil properties to determine the expected behaviorof the soils under different uses. Interpretations for allof the soils are field tested through observation of thesoils in different uses and under different levels ofmanagement. Some interpretations are modified to fitlocal conditions, and some new interpretations aredeveloped to meet local needs. Data are assembledfrom other sources, such as research information,production records, and field experience of specialists.For example, data on crop yields under defined levelsof management are assembled from farm records andfrom field or plot experiments on the same kinds ofsoil.

Predictions about soil behavior are based not onlyon soil properties but also on such variables asclimate and biological activity. Soil conditions arepredictable over long periods of time, but they are notpredictable from year to year. For example, soilscientists can predict with a fairly high degree ofaccuracy that a given soil will have a high water tablewithin certain depths in most years, but they cannotpredict that a high water table will always be at aspecific level in the soil on a specific date.

After soil scientists located and identified thesignificant natural bodies of soil in the survey area,they drew the boundaries of these bodies on aerialphotographs and identified each as a specific mapunit. Aerial photographs show trees, buildings, fields,roads, and rivers, all of which help in locatingboundaries accurately.

19

The general soil map at the back of this publicationshows broad areas that have a distinctive pattern ofsoils, relief, and drainage. Each map unit on thegeneral soil map is a unique natural landscape.Typically, it consists of one or more major soils ormiscellaneous areas and some minor soils ormiscellaneous areas. It is named for the major soils ormiscellaneous areas. The components of one map unitcan occur in another but in a different pattern.

The general soil map can be used to compare thesuitability of large areas for general land uses. Areasof suitable soils can be identified on the map. Likewise,areas where the soils are not suitable can beidentified.

Because of its small scale, the map is not suitablefor planning the management of a farm or field or forselecting a site for a road or building or other structure.The soils in any one map unit differ from place to placein slope, depth, drainage, and other characteristicsthat affect management.

Soils Dominantly on Flood Plains andTerraces

Three map units are on these landscape positions.They make up about 12 percent of the survey area.

1. Caples-Clato-Newberg

Very deep, artificially drained and well drained soils; onflood plains

This map unit makes up about 6 percent of thesurvey area. It is in the west-central part of the county.Slope is 0 to 3 percent. The vegetation is wetlandplants and deciduous and coniferous trees. Elevationis 10 to 300 feet. The mean annual precipitation is 40to 60 inches, the mean annual air temperature is about50 to 53 degrees F, and the growing season (at 28degrees) is 200 to 240 days.

Caples soils are very deep and artificially drained.They are on flood plains. They formed in mixedalluvium. Slope is 0 to 3 percent. Typically, these soilsare silty clay loam to a depth of 60 inches or more.

They are protected from seasonal flooding, but rareperiods of flooding can occur.

Clato soils are very deep and well drained. They areon flood plains. They formed in mixed alluvium. Slopeis 0 to 3 percent. Typically, these soils are silt loam to adepth of 60 inches or more. These soils are subject torare periods of flooding.

Newberg soils are very deep and well drained. Theyare on flood plains. They formed in mixed alluvium.Slope is 0 to 3 percent. Typically, the surface layer isfine sandy loam. The subsoil is fine sandy loam andvery fine sandy loam. The substratum to a depth of 60inches or more is loamy fine sand. These soils aresubject to occasional, brief periods of flooding.

Of minor extent in this unit are areas of Carrolls,Cowlitz, Godfrey, Greenwater, Pilchuck, andSnohomish soils.

This unit is used for cropland, hayland, pastureland,woodland (fig. 1), homesites, and industrialdevelopment.

2. Kelso-Kalama-Minniece

Very deep, somewhat poorly drained and moderatelywell drained soils; on terraces and terraceescarpments

This map unit makes up about 3 percent of thesurvey area. It is in the west-central part of the county,adjacent to the Cowlitz, Lewis, and Columbia Rivers.Slope is 0 to 60 percent. The vegetation is conifersand deciduous trees. Elevation is 50 to 500 feet. Themean annual precipitation is 40 to 60 inches, the meanannual air temperature is about 49 to 53 degrees F,and the growing season (at 28 degrees) is 220 to 240days.

Kelso soils are very deep and moderately welldrained. They are on high terraces. They formed in oldalluvium. Slope is 0 to 50 percent. Typically, thesurface layer is silt loam. The subsoil to a depth of 60inches or more is silty clay loam and silt loam. Aseasonal high water table is at a depth of 2 to 3 feet inDecember through March.

Kalama soils are very deep and moderately welldrained. They are on high terraces and terrace

General Soil Map Units

20 Soil Survey of

escarpments. They formed in old gravelly alluvium.Slope is 8 to 60 percent. Typically, the surface layerand subsurface layer are gravelly loam. The subsoil toa depth of 60 inches or more is gravelly clay loam andvery gravelly clay loam. A seasonal high water table isat a depth of 2.5 to 5.0 feet in December throughMarch.

Minniece soils are very deep and somewhat poorlydrained. They are on terraces. They formed inalluvium. Slope is 0 to 8 percent. Typically, the surfacelayer is silt loam. The subsoil to a depth of 60 inches ormore is silty clay and silty clay loam. A seasonal highwater table is at the surface to a depth of 2 feet belowthe surface in November through May.

Of minor extent in this unit are areas of Coweeman,Godfrey, Rose Valley, and Sara soils.

This unit is used for hayland, pastureland,homesites, wildlife habitat, and woodland.

3. Riverwash-Cowlitz-Delameter

Riverwash, and very deep, somewhat excessivelydrained soils; on flood plains and terraces

This map unit makes up about 3 percent of thesurvey area. It is in the northern part of the county,adjacent to the North and South Forks of the ToutleRiver (fig. 2). Slope is 0 to 30 percent. The vegetation

Figure 1.—Pastureland and woodland in an area of Caples silty clay loam, 0 to 3 percent slopes.


is willows and grasses. Elevation is 10 to 2,700 feet.The mean annual precipitation is 40 to 110 inches,the mean annual air temperature is about 40 to 51degrees F, and the growing season (at 28 degrees) is125 to 240 days.

Riverwash is very deep and somewhat poorlydrained to somewhat excessively drained. It is on

active river bottoms and flood plains. It formed inalluvium. Slope is 0 to 3 percent. Typically, it consistsof stratified cobbles, pebbles, sand, silt, and clay to adepth of 60 inches or more. It is subject to frequent,long periods of flooding in October through July.

Cowlitz soils are very deep and somewhatexcessively drained. They are on terraces and flood

Figure 2.—Area of general soil map unit 3. The soils in this unit formed in recent alluvium and debris flow from the 1980 eruption ofMount St. Helens.

22 Soil Survey of

plains. They formed in gravelly debris flow and gravellydredge material over mudflow. Slope is 0 to 30percent. Typically, these soils are extremely gravellysand and very gravelly sand to a depth of 60 inches ormore. Some areas of these soils are subject tooccasional, brief periods of flooding in Novemberthrough April.

Delameter soils are very deep and somewhatexcessively drained. They are on valley floors. Theyformed in avalanche debris flow. Typically, these soilsare extremely gravelly loamy sand to a depth of 60inches or more.

Of minor extent in this unit are areas of Lacamas,Solo, and Speelyai soils.

This unit is used for or has the potential to be usedfor wildlife habitat, woodland, pastureland, andrecreation.

Soils Dominantly on Warm Terraces andUplands

Ten map units are on these landscape positions.They make up about 57 percent of the survey area.

4. Loper-Bunker

Very deep and deep, well drained soils; on hillslopes,benches, ridgetops, and mountainslopes

This map unit makes up about 2 percent of thesurvey area. It is in the northwestern corner of thecounty. Slope is 5 to 65 percent. The vegetation isconifers. Elevation is 700 to 1,800 feet. The meanannual precipitation is 60 to 110 inches, the meanannual air temperature is 48 to 50 degrees F, and thegrowing season (at 28 degrees) is 180 to 240 days.

Loper soils are deep and well drained. They are onhillslopes and benches. They formed in colluviumderived from basalt with an admixture of loess andvolcanic ash over breccia and tuff. Slope is 20 to 65percent. Typically, the surface layer is silt loam. Thesubsoil to a depth of 60 inches or more is loam andclay loam.

Bunker soils are deep and well drained. They are onbenches, hillslopes, mountainslopes, and ridgetops.They formed in colluvium derived from basalt andvolcanic breccia. Slope is 5 to 65 percent. Typically, thesurface layer is silt loam. The subsoil is gravelly clayloam and loam. Fractured basalt is at a depth of 42inches. Depth to basalt ranges from 40 to 60 inches.

Of minor extent in this unit are areas of Boistfort,Katula, and Swem soils.

This unit is used for pastureland, recreation,watershed, woodland, and wildlife habitat.

5. Zenker-Lytell

Deep, well drained soils; on mountainslopes,hillslopes, and ridgetops

This map unit makes up about 1 percent of thesurvey area. It is in the western part of the county.Slope is 5 to 90 percent. The vegetation is conifers.Elevation is 800 to 1,800 feet. The mean annualprecipitation is 70 to 110 inches, the mean annual airtemperature is 48 to 50 degrees F, and the growingseason (at 28 degrees) is 200 to 240 days.

Zenker soils are deep and well drained. They are onmountainslopes. They formed in residuum andcolluvium derived from sandstone. Slope is 30 to 90percent. Typically, the surface layer is silt loam and thesubsoil is loam. Partly consolidated sandstone is at adepth of 41 inches. Depth to sandstone ranges from40 to 60 inches.

Lytell soils are deep and well drained. They are onhillslopes and ridgetops. They formed in residuum andcolluvium derived from siltstone and sandstone. Slopeis 5 to 75 percent. Typically, the surface layer is siltloam and the subsoil is silty clay loam. Partlyconsolidated, fractured, highly weathered siltstone isat a depth of 55 inches. Depth to siltstone ranges from40 to 60 inches.

Of minor extent in this unit are areas of Astoria andElochoman soils.

This unit is used for recreation, watershed,woodland, and wildlife habitat.

6. Centralia-Buckpeak

Very deep, well drained soils; on hillslopes, plateaus,and ridgetops


Centralia soils are very deep and well drained. Theyare on hillslopes, plateaus, and ridgetops. They formedin residuum and colluvium derived from sandstone.Slope is 0 to 30 percent. Typically, the surface layer issilt loam. The subsoil is clay loam. The substratum to adepth of 60 inches or more is loam.

Buckpeak soils are very deep and well drained.They are on hillslopes and ridgetops. They formed inresiduum and colluvium derived from siltstone andsandstone. Slope is 30 to 90 percent. Typically, thesurface layer and subsurface layer are silt loam. The


subsoil is silt loam. The substratum to a depth of 60inches or more is silty clay loam.

Of minor extent in this unit are areas of Astoria,Elochoman, Lytell, Melbourne, Vader, and Zenkersoils.

This unit is used for cropland, pastureland,woodland, homesites, and wildlife habitat.

7. Germany-Raught

Very deep and deep, well drained soils; onmountainslopes, hillslopes, ridgetops, benches, andplateaus


Germany soils are very deep and deep and are welldrained. They are on plateaus, ridgetops, benches,and hillslopes. They formed in residuum and colluviumderived from basalt and tuff with a mantle of loess andvolcanic ash. Slope is 0 to 65 percent. Typically, thesesoils are silt loam to a depth of 60 inches or more. Insome areas tuffaceous material is at a depth of 40 to60 inches.

Raught soils are very deep and well drained. Theyare on hillslopes and mountainslopes. They formed inresiduum and colluvium derived from basalt with anadmixture of volcanic ash and loess in the upper part.Slope is 20 to 90 percent. Typically, the surface layer issilt loam. The upper part of the subsoil is silt loam, andthe lower part to a depth of 60 inches or more is siltyclay loam.

Of minor extent in this unit are areas of Buckpeak,Camas, Centralia, Edgewick, Godfrey, Olequa,Olympic, and Stella soils.

This unit is used for cropland, pastureland,woodland, homesites, recreation, and wildlifehabitat.

8. Hazeldell-Olympic

Very deep and deep, well drained soils; on benches,terraces, hillslopes, and mountainslopes

This map unit makes up about 21 percent of thesurvey area. It is in the central part of the county.Slope is 2 to 65 percent. The vegetation is conifers.Elevation is 200 to 1,800 feet. The mean annualprecipitation is 40 to 70 inches, the mean annual airtemperature is about 50 to 52 degrees F, the growing

season (at 28 degrees) is 175 to 240 days, and thefrost-free period is 150 to 200 days.

Hazeldell soils are very deep and deep and are welldrained. They are on hillslopes. They formed inresiduum and colluvium derived from basalt. Slope is5 to 65 percent. Typically, the surface layer andsubsurface layer are gravelly silt loam. The subsoil isgravelly clay loam and very gravelly clay loam. Thesubstratum to a depth of 60 inches or more is verygravelly clay loam. In some areas tuffaceous materialis at a depth of 40 to 60 inches.

Olympic soils are very deep and deep and are welldrained. They are on benches, terraces, hillslopes, andmountainslopes. They formed in residuum andcolluvium derived from basalt or tuff. Slope is 2 to 65percent. Typically, the surface layer and subsurfacelayer are silt loam. The subsoil to a depth of 60 inchesor more is silty clay loam and silty clay. In some areastuffaceous material is at a depth of 40 to 60 inches.

Of minor extent in this unit are areas of Baumgard,Coweeman, Mart, Natal, Olequa, Rose Valley, Sara,Sauvola, Schneider, and Wyant soils.

This unit is used for cropland, pastureland,woodland, watershed, recreation, homesites, andwildlife habitat.

9. Seaquest-Sara

Very deep, moderately well drained and well drainedsoils; on terraces, terrace escarpments, and hills

This map unit makes up about 5 percent of thesurvey area. It is in the north-central part of the county.Slope is 0 to 40 percent. The vegetation is conifers.Elevation is 250 to 700 feet. The mean annualprecipitation is 45 to 60 inches, the mean annual airtemperature is about 48 to 51 degrees F, and thegrowing season (at 28 degrees) is 175 to 240 days.

Seaquest soils are very deep and well drained.They are on terraces and hills. They formed in oldalluvium and sediment derived from tuffaceoussiltstone and sandstone. Slope is 0 to 30 percent.Typically, the surface layer is silt loam. The subsoil to adepth of 60 inches or more is silty clay loam.

Sara soils are very deep and moderately welldrained. They are on terraces and terraceescarpments. They formed in old alluvium andsediment derived from tuffaceous siltstone andsandstone. Slope is 0 to 40 percent. Typically, thesurface layer is silt loam. The subsoil to a depth of 60inches or more is silty clay loam and silty clay. Aseasonal high water table is at a depth of 1 to 2 feet inDecember through April.

Of minor extent in this unit are areas of Baumgard,Godfrey, Greenwater, Hazeldell, Kosmos, Lacamas,

24 Soil Survey of

Olympic, Salkum, Sauvola, Schneider, Semiahmoo,Speelyai, and Wyant soils.

This unit is used for cropland, pastureland,woodland, homesites, recreation, and wildlife habitat.

10. Baumgard-Schneider

Deep, well drained soils; on benches, hillslopes,ridgetops, and mountainslopes

This map unit makes up about 6 percent of thesurvey area. It is in the northern part of the county.Slope is 5 to 90 percent. The vegetation is conifers.Elevation is 300 to 1,800 feet. The mean annualprecipitation is 50 to 75 inches, the mean annual airtemperature is about 48 to 50 degrees F, and thegrowing season (at 28 degrees) is 150 to 225 days.

Baumgard soils are deep and well drained soils.They are on benches, hillslopes, and ridgetops. Theyformed in volcanic ash and in residuum and colluviumderived from andesite and andesitic volcanic breccia.Slope is 5 to 65 percent. Typically, the surface layer issilt loam. The subsoil is gravelly clay loam and gravellysilty clay loam. Fractured andesite is at a depth of 50inches. Depth to andesite ranges from 40 to 60 inches.

Schneider soils are deep and well drained. They areon hillslopes and mountainslopes. They formed inresiduum and colluvium derived from andesite andandesitic breccia. Slope is 5 to 90 percent. Typically,the surface layer is very gravelly loam. The subsurfacelayer and subsoil are extremely gravelly loam.Fractured andesite is at a depth of 45 inches. Depth toandesite ranges from 40 to 60 inches.

Of minor extent in this unit are areas of Cinebar,Ferteg, Mulholland, Newaukum, and Siouxon soils.

This unit is used for pastureland, woodland,recreation, watershed, and wildlife habitat.

11. Gobar-Mulholland

Deep and very deep, well drained soils; on benches,toeslopes, hillslopes, mountainslopes, and ridgetops

This map unit makes up about 6 percent of thesurvey area. It is in the east-central part of the county.Slope is 5 to 90 percent. The vegetation is conifers.Elevation is 500 to 1,800 feet. The mean annualprecipitation is 70 to 90 inches, the mean annual airtemperature is 48 to 50 degrees F, and the growingseason (at 28 degrees) is 175 to 200 days.

Gobar soils are deep and well drained. They are onbenches, hillslopes, ridgetops, and mountainslopes.They formed in residuum and colluvium derived fromtuff and tuffaceous breccia with a mantle of volcanic

ash and loess. Slope is 5 to 90 percent. Typically,these soils are silt loam throughout. Fractured tuff is ata depth of 46 inches. Depth to tuff ranges from 40 to60 inches.

Mulholland soils are very deep and well drained.They are on benches, toeslopes, mountainslopes, andridgetops. They formed in residuum and colluviumderived from tuff and tuffaceous breccia with a mantleof volcanic ash and loess. Slope is 5 to 30 percent.Typically, the surface layer is silt loam. The subsoil issilty clay loam. The substratum to a depth of 60 inchesor more is silt loam.

Of minor extent in this unit are areas of Baumgard,Cinebar, Newaukum, Schneider, Siouxon, Winston,and Wyant soils.

This unit is used for pastureland, woodland,recreation, watershed, and wildlife habitat.

12. Cinebar-Newaukum-Siouxon

Very deep and deep, well drained soils; on benches,terraces, hillslopes, mountainslopes, and ridgetops

This map unit makes up about 3 percent of thesurvey area. It is in the eastern part of the county.Slope is 0 to 90 percent. The vegetation is conifers.Elevation is 300 to 1,800 feet. The mean annualprecipitation is 60 to 80 inches, the mean annual airtemperature is 48 to 50 degrees F, and the growingseason (at 28 degrees) is 150 to 200 days.

Cinebar soils are very deep and well drained. Theyare on benches, terraces, and hillslopes. They formedin volcanic ash over glaciofluvial deposits of volcanicash. Slope is 0 to 65 percent. Typically, these soils aresilt loam to a depth of 60 inches or more.

Newaukum soils are deep and very deep and arewell drained. They are on mountainslopes andhillslopes. They formed in colluvium and glaciofluvialdeposits derived from volcanic ash, till, and andesitewith an admixture of volcanic ash. Slope is 5 to 90percent. Typically, the surface layer is cobbly silt loam.The subsoil is gravelly silt loam and gravelly loam. Thesubstratum to a depth of 60 inches or more is gravellysilt loam. In some areas tuffaceous material is at adepth of 40 to 60 inches.

Siouxon soils are deep and well drained. They areon mountainslopes and ridgetops. They formed inresiduum and colluvium derived from andesite with anadmixture of volcanic ash. Slope is 5 to 90 percent.Typically, the surface layer is very cobbly silt loam. Thesubsoil is very cobbly loam and extremely cobblyloam. The substratum is extremely cobbly loam.Fractured andesite is at a depth of 55 inches. Depth toandesite ranges from 40 to 60 inches.


Of minor extent in this unit are areas of Baumgard,Schneider, Winston, and Wyant soils.

This unit is used for woodland, pastureland, wildlifehabitat, homesites, recreation, watershed, andcropland.

13. Yalelake-Zymer

Very deep, well drained soils; on terraces, terraceescarpments, hillslopes, and mountainslopes

This map unit makes up about 2 percent of thesurvey area. It is in the southeastern part of thecounty. Slope is 5 to 90 percent. The vegetation isconifers. Elevation is 300 to 1,800 feet. The meanannual precipitation is 80 to 120 inches, the meanannual air temperature is 48 to 50 degrees F, and thegrowing season (at 28 degrees) is 125 to 200 days.

Yalelake soils are very deep and well drained, Theyare on hillslopes, terraces, and terrace escarpments.They formed in glaciofluvial deposits of volcanic ashand pumice over pyroclastic material with a mantle ofvolcanic ash. Slope is 5 to 90 percent. Typically, thesurface layer and subsurface layer are sandy loam.The subsoil is gravelly sandy loam and sandy loam.The substratum to a depth of 60 inches or more isstratified sand to gravelly loam.

Zymer soils are very deep and well drained. Theyare on mountainslopes. They formed in residuum andcolluvium derived from volcanic ash and basic igneousrock with a mantle of volcanic ash and some pumice.Slope is 30 to 90 percent. Typically, the surface layer issandy loam. The upper part of the subsoil is gravellysandy loam, and the lower part to a depth of 60 inchesor more is very gravelly loam and extremely gravellyloam.

Of minor extent in this unit are areas of Cinebar andNewaukum soils.

This unit is used for woodland, wildlife habitat,recreation, and watershed.

Soils Dominantly on Cool Terraces andUplands

Five map units are on these landscape positions.They make up about 21 percent of the survey area.

14. Lates-Murnen

Moderately deep and very deep, well drained soils; onmountainslopes, mountain benches, and ridgetops

This map unit makes up about 1 percent of thesurvey area. It is in the northwestern part of the

county. Slope is 5 to 90 percent. The vegetation isconifers. Elevation is 1,800 to 2,600 feet. The meanannual precipitation is 80 to 110 inches, the meanannual air temperature is 43 to 45 degrees F, and thegrowing season (at 28 degrees) is 150 to 180 days.

Lates soils are moderately deep and well drained.They are on mountainslopes. They formed in residuumand colluvium derived from basalt. Slope is 5 to 90percent. Typically, the surface layer is silt loam and thesubsoil is gravelly silt loam. Fractured basalt is at adepth of 36 inches. Depth to basalt ranges from 20 to40 inches.

Murnen soils are very deep and well drained. Theyare on mountain benches and ridgetops. They formedin residuum derived from saprolitic basalt and volcanicbreccia with an admixture of volcanic ash and loess.Slope is 5 to 30 percent. Typically, these soils are siltloam to a depth of 60 inches or more.

Of minor extent in this unit are areas of Andaqueptsand Boistfort and Bunker soils.


15. Pheeney-Beigle

Deep and moderately deep, well drained soils; onbenches, mountainslopes, and broad ridgetops

This map unit makes up about 12 percent of thesurvey area. It is in the east-central part of the county.Slope is 5 to 90 percent. The vegetation is conifers.Elevation is 1,800 to 2,800 feet. The mean annualprecipitation is 60 to 100 inches, the mean annual airtemperature is 42 to 45 degrees F, and the growingseason (at 28 degrees) is 140 to 190 days.

Pheeney soils are moderately deep and welldrained. They are on benches, mountainslopes, andbroad ridgetops. They formed in residuum andcolluvium derived from andesite and andesitic flowbreccia with an admixture of volcanic ash. Slope is 5to 90 percent. Typically, the surface layer andsubsurface layer are gravelly silt loam. The subsoil isextremely cobbly silt loam. Fractured andesite is at adepth of 36 inches. Depth to andesite ranges from 20to 40 inches.

Beigle soils are deep and well drained. They are onmountainslopes and broad ridgetops. They formed inresiduum and colluvium derived from andesite andandesitic breccia with a mantle of volcanic ash andloess. Slope is 5 to 65 percent. Typically, the surfacelayer and subsurface layer are silt loam. The subsoil issilt loam and gravelly silt loam. The substratum is verygravelly loam. Fractured andesite is at a depth of 46inches. Depth to andesite ranges from 40 to 60 inches.

26 Soil Survey of

Of minor extent in this unit are areas of Dobbs,Jonas, Sarazan, Voight, Xeno, and Zynbar soils.

This unit is used for woodland, wildlife habitat,watershed, and recreation.

16. Hoffstadt-Domell

Deep and very deep, well drained soils; on benches,mountainslopes, and ridgetops

This map unit makes up about 4 percent of thesurvey area. It is in the northeastern part of the county.Slope is 5 to 90 percent. The vegetation is conifers.Elevation is 1,800 to 2,800 feet. The mean annualprecipitation is 70 to 90 inches, the mean annual airtemperature is 42 to 44 degrees F, and the growingseason (at 28 degrees) is 150 to 180 days.

Hoffstadt soils are deep and well drained. They areon mountainslopes, benches, and ridgetops. Theyformed in residuum and colluvium derived from basaltwith a mantle of volcanic ash. Slope is 5 to 90 percent.Typically, the surface layer is very gravelly sandy loam.The subsoil is very gravelly sandy loam and verycobbly sandy loam. The substratum is extremelystony sandy loam. Fractured basalt is at a depth of47 inches. Depth to basalt ranges from 40 to 60inches.

Domell soils are very deep and well drained. Theyare on benches, mountainslopes, and ridgetops. Theyformed in lahar and mudflow material with a highcontent of volcanic ash or pumiceous cinders. Slope is5 to 70 percent. Typically, the surface layer is sandyloam and the subsurface layer is loam. The subsoil issandy loam. The substratum to a depth of 60 inches ormore is loam and sandy loam.

Of minor extent in this unit are areas of Beigle,Dobbs, Pheeney, Xeno, and Zynbar soils.


17. Studebaker-Forsyth-Lithic UmbricVitrandepts

Very deep and shallow, well drained and somewhatexcessively drained soils; on fans, terraces, terraceescarpments, lava flows, and valley floors

This map unit makes up about 1 percent of thesurvey area. It is in the eastern part of the county.Slope is dominantly 0 to 90 percent. The vegetation isconifers and scattered shrubs and grasses. Elevationis 500 to 3,200 feet. The mean annual precipitation is70 to 140 inches, the mean annual air temperature is38 to 48 degrees F, and the growing season (at 28degrees) is 70 to 140 days.

Studebaker soils are very deep and somewhatexcessively drained. They are on valley floors. Theyformed in avalanche debris flow material. Slope is 0 to20 percent. Typically, these soils are very gravellyloamy sand and extremely gravelly loamy sand to adepth of 60 inches or more.

Forsyth soils are very deep and somewhatexcessively drained. They are on fans, terraces, andterrace escarpments. They formed in pyroclastic flowmaterial and lahar with an admixture of volcanic ashand pumice. Slope is 0 to 90 percent. Typically, thesurface layer is very cobbly loamy sand. The subsoil isvery cobbly loamy sand. The substratum to a depth of60 inches or more is extremely cobbly sand and verygravelly sand.

Lithic Umbric Vitrandepts are shallow and welldrained. They are on lava flows. They formed involcanic ash and pumice over basalt. Slope is 0 to 15percent. Typically, the surface layer is sandy loam. Thesubsoil is very gravelly loamy sand. Fractured basalt isat a depth of 11 inches. Depth to basalt ranges from10 to 20 inches.

Of minor extent in this unit are areas of Andaqueptsand Delameter soils.

This unit is used for woodland, wildlife habitat, andwatershed. Part of this unit is in the Mount St. HelensNational Geologic Monument.

18. Swift-Cinnamon

Very deep, well drained soils; on ridgetops,mountainslopes, and mountain benches

This map unit makes up about 3 percent of thesurvey area. It is in the

Soil Survey of Cowlitz County, Washington...100—Kelso silt loam, 0 to 8 percent slopes.....125....

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Transcript of Soil Survey of Cowlitz County, Washington...100—Kelso silt loam, 0 to 8 percent slopes.....125....