How to Use This Soil Survey

Detailed Soil Maps

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

To find information about your area of interest, you can locate the Section, Township, and Range by zooming in on the Index to Map Sheets, or you can go to the Web Soil Survey at (http://websoilsurvey.nrcs.usda.gov/app/).

Note the map unit symbols that are in that area. The Contents lists the map units by symbol and name and shows the page where each map unit is described.

See the Contents for sections of this publication that may address your specific needs. ii

This soil survey is a publication of the National Cooperative Soil Survey, a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local agencies. The Natural Resources Conservation Service (formerly the Soil Conservation Service) has leadership for the Federal part of the National Cooperative Soil Survey. Major fieldwork for this soil survey was completed in 1997. Soil names and descriptions were approved in 1997. Unless otherwise indicated, statements in this publication refer to conditions in the survey area in 1997. This survey was made cooperatively by the Natural Resources Conservation Service and the Montana Agricultural Experiment Station. It is part of the technical assistance furnished to the Sweet Grass County Conservation District. The most current official data are available through the NRCS Soil Data Mart website at http://soildatamart.nrcs.usda.gov. Soil maps in this survey may be copied without permission. Enlargement of these maps, 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 a larger scale. The United States Department of Agriculture (USDA) prohibits discrimination in all of its programs on the basis of race, color, national origin, gender, religion, age, disability, political beliefs, sexual orientation, and marital or family status. (Not all prohibited bases apply to all programs.) Persons with disabilities who require alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact the USDA’s TARGET Center at 202-720-2600 (voice or TDD). To file a complaint of discrimination, write USDA, Director, Office of Civil Rights, Room 326W, Whitten Building, 14th and Independence Avenue SW, Washington, DC 20250-9410, or call 202-720-5964 (voice or TDD). USDA is an equal opportunity provider and employer.

Cover: Two dominant features of the Sweet Grass County landscape are the Yellowstone River and Crazy Mountains. The river valley soils in this view are mainly Fairway and Korchea loams. Soils that are commonly found in the rangeland are Cabbart loam, Yawdim clay loam, and Reedpoint very channery loams. The high terraces in the background are mostly Roy and Tamaneen cobbly loams. Representative soils in the upper foothills are Adel loam on the rangeland and Stemple very cobbly loam in the forested areas.

Additional information about the Nation’s natural resources is available online from the Natural Resources Conservation Service at http://www.nrcs.usda.gov. iii

Contents

Part I Beaverton Series ...... 34 Beehive Series ...... 35 How To Use This Soil Survey ...... i Beenom Taxadjunct ...... 36 Alphabetical Index to Map Units ...... xiv Bigsag Family ...... 37 Summary of Tables ...... xxii Birney Series ...... 38 Foreword ...... xxv Blacksheep Series ...... 39 General Nature of the Survey Area ...... 1 Blossberg Taxadjunct...... 39 History and Development ...... 1 Bonebasin Series ...... 41 Industry, Transportation, and Recreation ...... 2 Bowery Series...... 42 Natural Resources ...... 3 Boxwell Series ...... 43 Physiography, Drainage, and Geology ...... 3 Breeton Series ...... 44 Mining ...... 9 Bridger Series ...... 44 Oil, Gas, and Coal ...... 10 Cabba Series ...... 46 Geothermal Resources ...... 10 Cabbart Series ...... 46 Ground-Water Resources ...... 10 Cambeth Series ...... 47 Seismicity...... 11 Castner Series ...... 48 Climate...... 11 Cheadle Series ...... 49 How This Survey Was Made ...... 12 Chinook Series ...... 50 Formation and Classification of the Soils ...... 17 Clunton Series ...... 51 Formation of the Soils ...... 17 Cowood Series ...... 52 Climate...... 17 Creed Series ...... 53 Living Organisms ...... 17 Danaher Series ...... 54 Topography ...... 18 Danvers Series ...... 56 Parent Material ...... 18 Delpoint Series ...... 57 Time ...... 19 Dimmick Series ...... 58 Classification of the Soils ...... 19 Doby Series ...... 59 Soil Series and Their Morphology...... 20 Doney Series ...... 59 Absarokee Series ...... 20 Duckcreek Series...... 60 Absher Family ...... 21 Elve Series ...... 61 Absher Series ...... 23 Ethridge Series ...... 62 Adel Series ...... 24 Evanston Series ...... 63 Albicalis Taxadjunct ...... 25 Fairfield Series ...... 64 Amherst Series ...... 26 Fairway Series ...... 66 Amor Series ...... 27 Farnuf Series ...... 67 Arrowpeak Series ...... 28 Fifer Series ...... 68 Ashbon Series ...... 29 Foolhen Series ...... 69 Attewan Series ...... 30 Frenchcreek Series ...... 70 Bacbuster Series ...... 31 Gerdrum Series ...... 71 Bearmouth Taxadjunct ...... 32 Gilispie Series ...... 72 Beaverell Series ...... 33 Greybear Series...... 73 iv

Havre Series ...... 74 Redfern Series ...... 116 Hinterland Series ...... 75 Reedpoint Series ...... 117 Klayent Series ...... 76 Reedwest Series...... 118 Knep Family ...... 78 Rentsac Series ...... 118 Knep Series ...... 78 Richey Series...... 119 Kobase Series ...... 79 Rocko Series ...... 120 Korchea Series ...... 80 Roy Series ...... 121 Kremlin Series ...... 81 Roy Taxadjunct ...... 122 Laceycreek Series ...... 82 Sagedale Series ...... 124 Lallie Family ...... 83 Sawicki Series ...... 125 Lap Series...... 84 Shambo Series ...... 126 Larry Series ...... 85 Shawmut Series ...... 127 Ledger Family ...... 87 Sieben Series ...... 128 Libeg Series ...... 88 Sinnigam Series ...... 129 Linwell Series ...... 89 Sixbeacon Series ...... 130 Lonna Series ...... 90 Soapcreek Series ...... 131 Lymanson Series ...... 91 Stemple Series ...... 133 Macar Series...... 92 Swampcreek Series ...... 134 Marcott Taxadjunct ...... 93 Sweetgrass Series ...... 135 Marmarth Series ...... 94 Sweetweed Series ...... 137 Martinsdale Series ...... 95 Tamaneen Series ...... 138 McIlwaine Series...... 96 Tanna Series ...... 139 Meadowcreek Series ...... 97 Thibadeau Series ...... 140 Meagher Series ...... 98 Tiban Series...... 141 Megonot Series ...... 100 Tibson Series ...... 142 Melville Series ...... 101 Ticell Series ...... 142 Merino Series ...... 102 Timberlin Series ...... 143 Millerlake Series ...... 103 Tongue River Series ...... 144 Monaberg Taxadjunct ...... 103 Turner Series ...... 145 Mowbray Series ...... 105 Twilight Series ...... 147 Mowbray Taxadjunct ...... 106 Vebar Series ...... 147 Nesda Series ...... 107 Vershal Series...... 148 Newtman Taxadjunct...... 108 Verson Series ...... 149 Novary Series ...... 109 Vision Series ...... 150 Overfelt Series ...... 110 Warwood Series ...... 151 Perma Series ...... 111 Wayden Series ...... 153 Pianohill Series ...... 112 Weedzunit Series ...... 153 Pintlar Series ...... 113 Whitlash Series ...... 154 Radersburg Series ...... 114 Whitore Series ...... 155 Redchief Series ...... 115 Winifred Series ...... 156 v

Winkler Series...... 157 129C—Tanna-Cabbart complex, 2 to 8 Winspect Series ...... 158 percent slopes ...... 181 Work Series ...... 159 129D—Tanna-Cabbart complex, 8 to 15 Worock Series...... 160 percent slopes ...... 182 Yamacall Series ...... 162 130C—Tanna-Hinterland clay loams, 2 to 8 Yawdim Series ...... 163 percent slopes ...... 182 Detailed Soil Map Units ...... 173 130D—Tanna-Hinterland clay loams, 8 to 15 100B—Nesda-Meadowcreek-Clunton loams, percent slopes ...... 183 0 to 4 percent slopes ...... 174 131D—Reedpoint very channery loam, 102B—Ledger family, clay loam, 1 to 4 2 to 15 percent slopes ...... 183 percent slopes ...... 174 131F—Reedpoint very channery loam, 103A—Havre loam, 0 to 2 percent slopes ...... 175 15 to 60 percent slopes ...... 183 104A—Meadowcreek loam, 0 to 2 percent 134B—Yamacall loam, 1 to 4 percent slopes ...... 175 slopes ...... 184 106B—Thibadeau loam, channeled, saline, 134C—Yamacall loam, 4 to 8 percent 0 to 4 percent slopes ...... 175 slopes ...... 184 107A—Nesda-McIlwaine loams, 0 to 2 134D—Yamacall loam, 8 to 15 percent percent slopes ...... 176 slopes ...... 184 109A—Meadowcreek-Nesda loams, 135A—Fairway loam, 0 to 2 percent 0 to 2 percent slopes ...... 176 slopes ...... 185 110D—Cabbart loam, 2 to 15 percent 138D—Cabbart-Megonot-Kobase clay loams, slopes ...... 177 2 to 15 percent slopes ...... 185 110E—Cabbart loam, 15 to 35 percent 139C—Cabbart-Delpoint loams, 2 to 8 slopes ...... 177 percent slopes ...... 186 112C—Cabbart-Delpoint, calcareous, loams, 139D—Cabbart-Delpoint loams, 8 to 15 2 to 8 percent slopes ...... 177 percent slopes ...... 186 112D—Cabbart-Delpoint, calcareous, loams, 139E—Cabbart-Delpoint loams, 15 to 35 8 to 15 percent slopes ...... 178 percent slopes ...... 187 112E—Cabbart-Delpoint, calcareous loams, 140F—Yawdim-Rentsac complex, 15 to 60 15 to 35 percent slopes ...... 178 percent slopes ...... 187 115D—Yawdim-Rentsac-Cabbart complex, 141C—Marmarth-Cabbart loams, 2 to 8 2 to 15 percent slopes ...... 179 percent slopes ...... 188 116F—Cabbart-Rock outcrop complex, 141D—Marmarth-Cabbart loams, 8 to 15 15 to 60 percent slopes ...... 179 percent slopes ...... 188 117C—Cabbart-Tanna complex, 2 to 8 142C—Tanna clay loam, 2 to 8 percent percent slopes ...... 180 slopes ...... 189 118C—Hinterland clay loam, 0 to 8 percent 144B—Evanston loam, 0 to 4 percent slopes ...... 180 slopes ...... 189 127C—Marmarth loam, 2 to 8 percent 144C—Evanston loam, 4 to 8 percent slopes ...... 181 slopes ...... 189 vi

144D—Evanston loam, 8 to 15 percent 163C—Absher clay, 0 to 8 percent slopes ...... 198 slopes ...... 190 166B—Richey silty clay, 0 to 4 percent 145C—Boxwell, calcareous-Cabbart loams, slopes ...... 199 2 to 8 percent slopes ...... 190 166C—Richey silty clay, 4 to 8 percent 146B—Ethridge clay loam, 1 to 4 percent slopes ...... 199 slopes ...... 190 167F—Yawdim-Birney-Rock outcrop complex, 146C—Ethridge clay loam, 4 to 8 percent 15 to 60 percent slopes ...... 199 slopes ...... 191 168D—Chinook fine sandy loam, 8 to 15 147B—Kremlin loam, 0 to 4 percent slopes .... 191 percent slopes ...... 200 147C—Kremlin loam, 4 to 8 percent slopes .... 191 169C—Ethridge-Tanna clay loams, 2 to 8 147D—Kremlin loam, 8 to 15 percent percent slopes ...... 200 slopes ...... 192 170C—Gerdrum-Creed complex, 0 to 8 148E—Cabbart-Cambeth complex, 4 to 35 percent slopes ...... 201 percent slopes ...... 192 172C—Tanna-Boxwell, calcareous, complex, 150C—Kobase clay loam, 2 to 8 percent 2 to 8 percent slopes ...... 201 slopes ...... 193 172D—Tanna-Boxwell, calcareous, complex, 150D—Kobase clay loam, 8 to 15 percent 8 to 15 percent slopes ...... 202 slopes ...... 193 174C—Sweetgrass clay loam, 2 to 8 percent 151C—Cabbart-Boxwell loams, 2 to 8 slopes ...... 202 percent slopes ...... 193 176C—Reedwest-Cabba loams, 2 to 8 151D—Cabbart-Boxwell loams, 8 to 15 percent slopes ...... 202 percent slopes ...... 194 178F—Castner-Roy complex, 15 to 60 153C—Ethridge-Reedpoint complex, 2 to 8 percent slopes ...... 203 percent slopes ...... 194 179F—Cabba-Rock outcrop complex, 153D—Ethridge-Reedpoint complex, 8 to 15 15 to 60 percent slopes ...... 203 percent slopes ...... 195 181C—Cabba-Winifred clay loams, 2 to 8 154E—Evanston-Reedpoint complex, 8 to 35 percent slopes ...... 204 percent slopes ...... 195 181D—Cabba-Winifred clay loams, 8 to 15 155E—Cabbart-Delpoint loams, moist, percent slopes ...... 204 15 to 35 percent slopes ...... 196 182C—Roy gravelly clay loam, 2 to 8 percent 156C—Twilight-Blacksheep fine sandy loams, slopes ...... 205 2 to 8 percent slopes ...... 196 182D—Roy gravelly clay loam, 8 to 15 157F—Cabbart, moist-Delpoint-Rock outcrop percent slopes ...... 205 complex, 15 to 60 percent slopes...... 197 183A—Tamaneen gravelly loam, 0 to 2 159A—Marcott cobbly clay loam, 0 to 2 percent slopes ...... 206 percent slopes ...... 197 183B—Tamaneen clay loam, 0 to 4 percent 161B—Martinsdale gravelly loam, 0 to 4 slopes ...... 206 percent slopes ...... 198 183C—Tamaneen gravelly clay loam, 2 to 8 161C—Martinsdale gravelly loam, 4 to 8 percent slopes ...... 206 percent slopes ...... 198 vii

184D—Absarokee-Shambo loams, 8 to 15 206D—Hinterland-Rentsac-Cabbart complex, percent slopes ...... 206 2 to 15 percent slopes ...... 215 185C—Amor-Castner complex, 2 to 8 208F—Cabba-Castner complex, 15 to 60 percent slopes ...... 207 percent slopes ...... 216 185D—Amor-Castner complex, 8 to 15 209C—Fairfield gravelly loam, 2 to 8 percent percent slopes ...... 207 slopes ...... 216 186D—Castner channery loam, 2 to 15 209D—Fairfield gravelly loam, 8 to 15 percent slopes ...... 208 percent slopes ...... 216 186E—Castner channery loam, 15 to 35 210D—Cabba loam, 2 to 15 percent slopes .... 217 percent slopes ...... 208 210E—Cabba loam, 15 to 35 percent 188C—Linwell clay loam, 2 to 8 percent slopes ...... 217 slopes ...... 209 213A—Korchea-Fairway-Albicalis loams, 189C—Shambo gravelly clay loam, 2 to 8 channeled, 0 to 4 percent slopes ...... 217 percent slopes ...... 209 215B—Macar loam, calcareous surface, 190C—Danvers gravelly clay loam, 2 to 8 0 to 4 percent slopes ...... 218 percent slopes ...... 209 215C—Macar loam, calcareous surface, 191C—Castner-Farnuf complex, 2 to 8 4 to 8 percent slopes ...... 218 percent slopes ...... 209 215D—Macar loam, 8 to 15 percent slopes .... 219 192D—Castner-Shambo complex, 8 to 15 216A—Clunton clay loam, 0 to 2 percent percent slopes ...... 210 slopes ...... 219 193C—Farnuf-Winifred complex, 2 to 8 217A—Korchea loam, 0 to 2 percent percent slopes ...... 210 slopes ...... 219 194C—Linwell-Amor complex, 2 to 8 percent 218C—Breeton sandy loam, 2 to 8 percent slopes ...... 211 slopes ...... 220 196B—Yamacall-Bigsag family complex, 218D—Breeton sandy loam, 8 to 15 percent 0 to 4 percent slopes ...... 211 slopes ...... 220 197C—Work-Castner complex, 2 to 8 219A—Klayent clay loam, 0 to 2 percent percent slopes ...... 212 slopes ...... 220 197D—Work-Castner complex, 8 to 15 220C—Amor-Work complex, 2 to 8 percent percent slopes ...... 212 slopes ...... 221 201F—Yawdim-Rock outcrop complex, 220D—Amor-Work complex, 8 to 15 percent 15 to 60 percent slopes ...... 213 slopes ...... 221 202C—Castner-Absarokee complex, 2 to 8 221C—Amor-Farnuf loams, 2 to 8 percent percent slopes ...... 213 slopes ...... 222 202D—Castner-Absarokee complex, 8 to 15 224B—Shambo loam, 0 to 4 percent slopes ... 222 percent slopes ...... 214 224C—Shambo loam, 4 to 8 percent slopes ... 222 202E—Castner-Absarokee complex, 15 to 35 224D—Shambo loam, 8 to 15 percent percent slopes ...... 214 slopes ...... 223 204A—Dimmick silty clay, 0 to 2 percent 225C—Amor-Cabba loams, 2 to 8 percent slopes ...... 215 slopes ...... 223 viii

225D—Amor-Cabba loams, 8 to 15 percent 253C—Reedwest-Castner complex, 2 to 8 slopes ...... 224 percent slopes ...... 232 227F—Cabba, moist-Rock outcrop complex, 253D—Reedwest-Castner complex, 8 to 15 15 to 60 percent slopes ...... 224 percent slopes ...... 233 229C—Absarokee-Cabba loams, 2 to 8 253E—Reedwest-Castner complex, 15 to 35 percent slopes ...... 224 percent slopes ...... 233 229D—Absarokee-Cabba loams, 8 to 15 254C—Winifred clay loam, 2 to 8 percent percent slopes ...... 225 slopes ...... 234 230B—Farnuf loam, 0 to 4 percent slopes ...... 225 255B—Thibadeau, saline-Absher family 230C—Farnuf loam, 4 to 8 percent slopes ...... 226 complex, 0 to 8 percent slopes...... 234 230D—Farnuf loam, 8 to 15 percent 256F—Sixbeacon-Reedpoint complex, slopes ...... 226 15 to 60 percent slopes ...... 235 231C—Doney-Cabba loams, 2 to 8 percent 257B—Absher-Bigsag families, clays, 0 to 4 slopes ...... 226 percent slopes ...... 235 231D—Doney-Cabba loams, 8 to 15 percent 259D—Wayden clay, 2 to 15 percent slopes ... 236 slopes ...... 227 260C—Wayden-Doney complex, 2 to 8 232B—Work loam, 0 to 4 percent slopes ...... 227 percent slopes ...... 236 232C—Work loam, 4 to 8 percent slopes ...... 228 261C—Absarokee-Wayden complex, 2 to 8 236B—Verson loam, 0 to 4 percent slopes ..... 228 percent slopes ...... 236 236C—Verson loam, 4 to 8 percent slopes ..... 228 262D—Wayden-Castner-Cabba complex, 237B—Thibadeau loam, saline, 0 to 4 2 to 15 percent slopes ...... 237 percent slopes ...... 229 265C—Sagedale clay loam, 2 to 8 percent 238C—Sagedale-Cabba complex, 2 to 8 slopes ...... 237 percent slopes ...... 229 265D—Sagedale clay loam, 8 to 15 percent 238F—Sagedale-Cabba complex, 8 to 35 slopes ...... 238 percent slopes ...... 229 266B—Sweetgrass clay, 0 to 4 percent 239C—Sixbeacon gravelly loam, 2 to 8 slopes ...... 238 percent slopes ...... 230 267B—Beaverton gravelly sandy clay loam, 241D—Yawdim clay loam, 2 to 15 percent 0 to 4 percent slopes ...... 238 slopes ...... 230 268B—Overfelt-Roy complex, 0 to 4 percent 245C—Lonna silt loam, 2 to 8 percent slopes ...... 239 slopes ...... 231 269C—Danvers loam, 2 to 8 percent slopes ... 239 249B—Soapcreek clay loam, 0 to 2 percent 270C—Bacbuster-Castner complex, 2 to 8 slopes ...... 231 percent slopes ...... 239 250A—Lallie family, silty clay, 0 to 2 percent 270D—Bacbuster-Castner complex, 8 to 15 slopes ...... 231 percent slopes ...... 240 251B—Radersburg gravelly loam, 0 to 4 271B—Sweetgrass gravelly loam, 0 to 4 percent slopes ...... 232 percent slopes ...... 240 252B—Roy-Swampcreek complex, 0 to 4 274B—Work clay loam, 0 to 4 percent percent slopes ...... 232 slopes ...... 241 ix

274C—Work clay loam, 4 to 8 percent 295B—Roy-Turner complex, 0 to 4 percent slopes ...... 241 slopes ...... 248 274D—Work clay loam, 8 to 15 percent 296B—Blossberg cobbly loam, 0 to 4 percent slopes ...... 241 slopes ...... 249 274E—Work clay loam, 15 to 35 percent 303D—Winspect cobbly loam, 4 to 15 percent slopes ...... 242 slopes ...... 249 275B—Overfelt clay loam, 0 to 4 percent 303E—Winspect very cobbly loam, 15 to 35 slopes ...... 242 percent slopes ...... 249 276A—Larry clay loam, 0 to 2 percent 304C—Shawmut-Shambo complex, 2 to 8 slopes ...... 242 percent slopes ...... 250 277B—Marcott-Larry complex, 0 to 4 percent 304D—Shawmut-Shambo complex, 8 to 15 slopes ...... 243 percent slopes ...... 250 278B—Perma gravelly loam, 0 to 4 percent 307E—Cabba-Doney loams, 8 to 35 percent slopes ...... 243 slopes ...... 251 278C—Perma gravelly loam, 4 to 8 percent 308C—Meagher gravelly loam, 2 to 8 percent slopes ...... 243 slopes ...... 251 279C—Shambo clay loam, calcareous, 4 to 8 309E—Ticell-Amor loams, 8 to 35 percent percent slopes ...... 244 slopes ...... 251 281F—Shawmut-Castner complex, 15 to 60 310E—Winspect-Ticell complex, 15 to 35 percent slopes ...... 244 percent slopes ...... 252 282B—Bowery clay loam, 0 to 4 percent 311C—Roy, extremely stony-Turner complex, slopes ...... 245 2 to 8 percent slopes ...... 252 283F—Castner-Wayden complex, moist, 312D—Vershal very channery loam, 2 to 15 15 to 60 percent slopes ...... 245 percent slopes ...... 253 284C—Shawmut gravelly loam, 2 to 8 312F—Vershal very channery loam, 15 to 60 percent slopes ...... 245 percent slopes ...... 253 284D—Shawmut gravelly loam, 8 to 15 313C—Roy-Tamaneen complex, 2 to 8 percent slopes ...... 246 percent slopes ...... 254 286F—Wayden-Rock outcrop complex, 330C—Absarokee-Amherst complex, 2 to 8 15 to 60 percent slopes ...... 246 percent slopes ...... 254 288B—Turner sandy clay loam, 0 to 4 330D—Absarokee-Amherst complex, 8 to 15 percent slopes ...... 246 percent slopes ...... 254 289A—Swampcreek gravelly sandy clay loam, 331F—Wayden-Castner complex, 15 to 60 0 to 2 percent slopes ...... 247 percent slopes ...... 255 290C—Breeton loam, 2 to 8 percent 332D—Ticell loam, 2 to 15 percent slopes ...... 255 slopes ...... 247 332E—Ticell loam, 15 to 35 percent slopes .... 256 291B—Beaverton very cobbly loam, 0 to 4 333F—Shawmut-Castner-Rock outcrop percent slopes ...... 247 complex, 15 to 60 percent slopes...... 256 294B—Roy gravelly loam, 0 to 4 percent 335D—Cabba-Castner-Amherst complex, slopes ...... 248 2 to 15 percent slopes ...... 257 x

336E—Sinnigam-Wayden complex, moist, 356D—Redchief gravelly loam, 4 to 15 15 to 45 percent slopes ...... 257 percent slopes ...... 268 337C—Work gravelly clay loam, 2 to 8 357D—Cabba-Vershal complex, 4 to 15 percent slopes ...... 258 percent slopes ...... 268 337D—Work gravelly clay loam, 8 to 15 357E—Cabba-Vershal complex, 15 to 45 percent slopes ...... 258 percent slopes ...... 269 342E—Ashbon-Winkler-Weedzunit complex, 358E—Tongue River-Danaher loams, 15 to 35 percent slopes ...... 258 15 to 35 percent slopes ...... 269 343F—Ashbon-Winkler-Rock outcrop 359F—Fifer-Cheadle-Monaberg complex, complex, 35 to 60 percent slopes...... 259 25 to 60 percent slopes ...... 270 344F—Vision-Sweetweed-Whitlash complex, 360D—Knep family-Warwood loams, 4 to 15 25 to 60 percent slopes ...... 260 percent slopes ...... 270 345D—Weedzunit-Ashbon complex, 4 to 15 361E—Cowood very channery loam, 4 to 25 percent slopes ...... 260 percent slopes ...... 271 345E—Weedzunit-Ashbon complex, 15 to 45 362F—Wayden-Castner-Rock outcrop percent slopes ...... 261 complex, 25 to 60 percent slopes...... 271 346E—Farnuf-Reedwest-Shawmut complex, 363E—Kobase-Rentsac-Megonot complex, 15 to 35 percent slopes ...... 261 4 to 25 percent slopes ...... 272 347D—Cheadle-Lymanson-Gilispie complex, 364E—Absarokee-Bowery loams, 15 to 45 2 to 15 percent slopes ...... 262 percent slopes ...... 272 347E—Cheadle-Lymanson-Gilispie complex, 365C—Megonot-Cabbart complex, 2 to 8 15 to 35 percent slopes ...... 262 percent slopes ...... 273 348E—Lymanson-Cheadle-Adel complex, 366C—Tanna, calcareous,-Rentsac complex, 8 to 35 percent slopes ...... 263 2 to 8 percent slopes ...... 273 349D—Cheadle channery loam, 2 to 15 366D—Tanna, calcareous,-Rentsac complex, percent slopes ...... 264 8 to 15 percent slopes ...... 274 350F—Castner-Mowbray-Rock outcrop 367D—Rentsac-Reedpoint complex, 2 to 15 complex, 25 to 60 percent slopes...... 264 percent slopes ...... 274 351D—Whitlash-Pianohill complex, 4 to 15 367E—Rentsac-Reedpoint complex, 15 to 35 percent slopes ...... 265 percent slopes ...... 275 351E—Whitlash-Pianohill complex, 15 to 35 368E—Rentsac-Tanna-Rock outcrop complex, percent slopes ...... 265 8 to 35 percent slopes ...... 275 352E—Perma-Rock outcrop complex, 369D—Rentsac-Tanna complex, 2 to 15 15 to 45 percent slopes ...... 266 percent slopes ...... 276 353F—Ashbon-Rock outcrop-Winkler 369E—Rentsac-Tanna complex, 15 to 35 complex, 35 to 60 percent slopes...... 266 percent slopes ...... 276 354F—Vision-Whitlash-Rock outcrop 370D—Greybear-Rentsac complex, 2 to 15 complex, 35 to 60 percent slopes...... 267 percent slopes ...... 277 355F—Doney-Cabba, moist loams, 35 to 60 371D—Whitlash cobbly sandy loam, 2 to 15 percent slopes ...... 267 percent slopes ...... 277 xi

371E—Whitlash cobbly sandy loam, 15 to 35 394D—Whitlash-Beenom complex, 4 to 15 percent slopes ...... 278 percent slopes ...... 288 372D—Castner-Amherst complex, 2 to 15 395E—Whitlash-Beenom-Bacbuster complex, percent slopes ...... 278 8 to 25 percent slopes ...... 289 372E—Castner-Amherst complex, 15 to 35 396C—Soapcreek-Lallie family complex, percent slopes ...... 278 0 to 8 percent slopes ...... 289 373D—Ticell-Castner complex, 2 to 15 397E—Castner-Laceycreek-Bowery complex, percent slopes ...... 279 8 to 25 percent slopes ...... 290 374F—Cabbart, moist-Delpoint-Rock outcrop 397F—Castner-Laceycreek-Bowery complex, complex, 15 to 45 percent slopes...... 279 25 to 60 percent slopes ...... 290 375D—Cabbart-Rentsac, moist, complex, 398F—Cabba very cobbly loam, 15 to 60 2 to 15 percent slopes ...... 280 percent slopes ...... 291 376E—Chinook-Twilight fine sandy loams, 399F—Reedwest-Cabba-Castner complex, 8 to 25 percent slopes ...... 280 15 to 60 percent slopes ...... 291 377F—Tongue River-Cabba, moist-Adel 400D—Bowery-Nesda-Bonebasin complex, loams, 15 to 60 percent slopes ...... 281 2 to 15 percent slopes ...... 292 378D—Melville cobbly loam, 2 to 15 percent 401B—Roy cobbly loam, 0 to 4 percent slopes, stony ...... 282 slopes ...... 293 379F—Tongue River-Arrowpeak, moist 402F—Reedwest-Rock outcrop complex, complex, 15 to 60 percent slopes...... 282 15 to 60 percent slopes, very stony...... 293 381E—Duckcreek-Arrowpeak complex, 403F—Cabba-Castner-Rock outcrop complex, 8 to 45 percent slopes ...... 282 moist, 25 to 60 percent slopes ...... 293 382E—Fifer-Knep complex, 15 to 45 percent 404F—Lymanson-Doby-Rock outcrop slopes ...... 283 complex, 15 to 60 percent slopes...... 294 383D—Fifer-Rock outcrop complex, 4 to 15 405F—Tongue River-Doby-Rock outcrop percent slopes ...... 283 complex, 15 to 60 percent slopes...... 295 384E—Fifer-Cheadle complex, 15 to 45 406E—Doney-Macar loams, 4 to 25 percent percent slopes ...... 284 slopes ...... 295 385E—Millerlake-Arrowpeak-Adel complex, 407F—Danaher-Timberlin complex, 25 to 60 8 to 35 percent slopes ...... 284 percent slopes ...... 296 386D—Millerlake loam, 4 to 15 percent 408E—Warwood-Timberlin-Cowood complex, slopes ...... 285 8 to 35 percent slopes ...... 296 387E—Tongue River-Novary-Cowood 408F—Warwood-Timberlin-Cowood complex, complex, 4 to 45 percent slopes...... 285 35 to 60 percent slopes ...... 297 388D—Adel loam, 2 to 15 percent slopes ...... 286 409F—Merino-Elve-Rock outcrop complex, 391F—Tongue River-Timberlin complex, 25 to 80 percent slopes ...... 297 35 to 60 percent slopes ...... 286 410E—Adel-Timberlin complex, 8 to 35 392E—Doney-Vershal complex, 8 to 35 percent slopes ...... 298 percent slopes ...... 287 411E—Pianohill-Whitlash-Adel complex, 393E—Vershal-Reedwest complex, 8 to 35 15 to 45 percent slopes ...... 299 percent slopes ...... 287 xii

412E—Lap-Winspect-Rock outcrop complex, 430E—Mowbray-Bridger-Novary complex, 8 to 35 percent slopes ...... 299 0 to 35 percent slopes ...... 309 412F—Lap-Winspect complex, 35 to 70 431C—Bearmouth-Tiban-Beehive complex, percent slopes ...... 300 0 to 8 percent slopes ...... 310 413E—Cabba-Bowery complex, 2 to 60 432E—Wayden-Amherst-Winifred complex, percent slopes ...... 300 8 to 45 percent slopes ...... 310 414D—Libeg, extremely bouldery-Adel 433D—Monaberg loam, 4 to 15 percent complex, 4 to 15 percent slopes...... 301 slopes ...... 311 414F—Libeg-Libeg, extremely bouldery-Adel 434F—Redchief-Arrowpeak, moist complex, complex, 15 to 60 percent slopes...... 301 15 to 60 percent slopes ...... 311 415F—Rocko-Adel complex, 15 to 45 percent 435C—Bridger clay loam, 2 to 8 percent slopes ...... 302 slopes ...... 312 416C—Bearmouth, moist-Beehive complex, 436D—Bowery loam, 2 to 15 percent 2 to 8 percent slopes, extremely stony ...... 302 slopes ...... 312 417B—Melville cobbly loam, 0 to 4 percent 437E—Cabba-Castner-Work complex, slopes ...... 303 4 to 35 percent slopes, bouldery ...... 313 418D—Melville cobbly loam, 4 to 15 percent 438F—Wayden-Castner complex, 15 to 60 slopes ...... 303 percent slopes, bouldery ...... 313 419E—Winspect-Work-Bowery, 8 to 35 439B—Fairway-Korchea loams, channeled, percent slopes, extremely bouldery ...... 303 0 to 4 percent slopes ...... 314 420E—Tibson, extremely bouldery-Bridger, 440C—Marmarth-Rentsac complex, 2 to 8 extremely bouldery-Adel complex, 8 to 35 percent slopes ...... 314 percent slopes ...... 304 440D—Marmarth-Rentsac complex, 8 to 15 421E—Sawicki, extremely bouldery-Bowery percent slopes ...... 315 complex, 4 to 25 percent slopes...... 305 441D—Yawdim-Delpoint complex, 2 to 15 422C—Work, stony-Bowery complex, 2 to 8 percent slopes ...... 315 percent slopes ...... 305 442C—Tanna-Yawdim complex, 2 to 8 422E—Work, very stony-Bowery complex, percent slopes ...... 316 8 to 35 percent slopes ...... 306 443B—Sieben-Attewan gravelly loams, 0 to 4 424C—Bridger, very stony-Adel complex, percent slopes ...... 316 2 to 8 percent slopes ...... 306 444C—Boxwell-Ethridge complex, 2 to 8 424E—Bridger, very stony-Adel complex, percent slopes ...... 317 8 to 35 percent slopes ...... 307 444D—Boxwell-Ethridge complex, 8 to 15 425E—Pintlar-Bridger loams, 4 to 35 percent percent slopes ...... 317 slopes ...... 307 445C—Evanston-Tanna complex, 2 to 8 426F—Stemple-Worock complex, 35 to 70 percent slopes ...... 318 percent slopes, very stony ...... 308 446B—Beaverell very cobbly loam, 0 to 4 428F—Tibson-Whitore-Rock outcrop complex, percent slopes ...... 318 35 to 70 percent slopes ...... 308 447B—Frenchcreek very gravelly loam, 2 to 4 429E—Work-Roy, bouldery-Bigsag family percent slopes ...... 318 complex, 2 to 35 percent slopes...... 309 xiii

448B—Attewan loam, 0 to 4 percent slopes .... 319 Summary of Tables ...... xii 449E—Redchief very stony loam, 15 to 35 Agronomy ...... 11 percent slopes ...... 319 Crops and Pasture ...... 11 450D—Sieben gravelly loam, 2 to 15 percent Cropland Management ...... 11 slopes ...... 319 Land Capability Classification...... 11 451F—Rentsac-Radersburg complex, Prime Farmland and Other Important 15 to 60 percent slopes ...... 320 Farmland ...... 12 452D—Redchief-Melville complex, 4 to 15 Rangeland ...... 101 percent slopes ...... 320 Rangeland Condition ...... 102 453D—Libeg very cobbly sandy loam, 2 to 15 Rangeland Management ...... 102 percent slopes ...... 321 Forestland Understory Management ...... 103 453E—Libeg very cobbly sandy loam, Forestland ...... 371 15 to 35 percent slopes ...... 321 Forest Resource Statistics ...... 371 454F—Redfern-Warwood complex, 25 to 70 Fire Protection ...... 371 percent slopes ...... 321 Cover Types ...... 371 455F—Redfern-Fifer complex, 25 to 60 Parent Material ...... 371 percent slopes ...... 322 Forested Areas ...... 371 456F—Stemple-Cheadle, moist, complex, Forestland Management and Productivity ...... 373 25 to 70 percent slopes ...... 322 Soil Interpretations ...... 373 457D—Arrowpeak-Gilispie-Fifer complex, Soil Rating and Limitations ...... 373 2 to 15 percent slopes ...... 323 Forestland Productivity ...... 374 458C—Vebar-Castner complex, 2 to 8 Yields ...... 374 percent slopes ...... 323 Forest Understory ...... 374 459A—Newtman muck, 0 to 2 percent Recreation...... 389 slopes ...... 324 Wildlife Habitat ...... 391 460B—Foolhen-Beehive-Bearmouth complex, Elements of Wildlife Habitat ...... 391 0 to 4 percent slopes ...... 324 Kinds of Wildlife Habitat ...... 392 461B—Soapcreek-Absher family complex, Wildlife of the Sweet Grass County Area ...... 392 0 to 4 percent slopes ...... 325 Engineering ...... 393 DA—Denied access ...... 325 Building Site Development ...... 393 M-W—Water, miscellaneous ...... 326 Sanitary Facilities ...... 394 W—Water ...... 326 Construction Materials ...... 394 References ...... 327 Soil Properties ...... 497 Glossary ...... 329 Engineering Index Properties ...... 497 Physical Properties ...... 498 Chemical Properties ...... 499 Part II Water Features ...... 500 Soil Features ...... 501 How To Use This Soil Survey ...... i References ...... 813 Detailed Soil Map Unit Legend ...... iv Glossary ...... 815

Issued 2004 xiv

Alphabetical Index to Map Units

330C—Absarokee-Amherst complex, 2 to 8 342E—Ashbon-Winkler-Weedzunit complex, percent slopes ...... 254 15 to 35 percent slopes ...... 258 330D—Absarokee-Amherst complex, 8 to 15 448B—Attewan loam, 0 to 4 percent slopes ...... 319 percent slopes ...... 254 270C—Bacbuster-Castner complex, 2 to 8 364E—Absarokee-Bowery loams, 15 to 45 percent slopes ...... 239 percent slopes ...... 272 270D—Bacbuster-Castner complex, 8 to 15 229C—Absarokee-Cabba loams, 2 to 8 percent percent slopes ...... 240 slopes ...... 224 416C—Bearmouth, moist-Beehive complex, 229D—Absarokee-Cabba loams, 8 to 15 2 to 8 percent slopes, extremely stony ...... 302 percent slopes ...... 225 431C—Bearmouth-Tiban-Beehive complex, 184D—Absarokee-Shambo loams, 8 to 15 0 to 8 percent slopes ...... 310 percent slopes ...... 206 446B—Beaverell very cobbly loam, 0 to 4 261C—Absarokee-Wayden complex, 2 to 8 percent slopes ...... 318 percent slopes ...... 236 267B—Beaverton gravelly sandy clay loam, 163C—Absher clay, 0 to 8 percent slopes ...... 198 0 to 4 percent slopes ...... 238 257B—Absher-Bigsag families, clays, 0 to 4 291B—Beaverton very cobbly loam, 0 to 4 percent slopes ...... 235 percent slopes ...... 247 388D—Adel loam, 2 to 15 percent slopes ...... 286 296B—Blossberg cobbly loam, 0 to 4 percent 410E—Adel-Timberlin complex, 8 to 35 percent slopes ...... 249 slopes ...... 298 282B—Bowery clay loam, 0 to 4 percent 225C—Amor-Cabba loams, 2 to 8 percent slopes ...... 245 slopes ...... 223 436D—Bowery loam, 2 to 15 percent slopes...... 312 225D—Amor-Cabba loams, 8 to 15 percent 400D—Bowery-Nesda-Bonebasin complex, slopes ...... 224 2 to 15 percent slopes ...... 292 185C—Amor-Castner complex, 2 to 8 percent 145C—Boxwell, calcareous-Cabbart loams, slopes ...... 207 2 to 8 percent slopes ...... 190 185D—Amor-Castner complex, 8 to 15 percent 444C—Boxwell-Ethridge complex, 2 to 8 slopes ...... 207 percent slopes ...... 317 221C—Amor-Farnuf loams, 2 to 8 percent 444D—Boxwell-Ethridge complex, 8 to 15 slopes ...... 222 percent slopes ...... 317 220C—Amor-Work complex, 2 to 8 percent 290C—Breeton loam, 2 to 8 percent slopes ...... 247 slopes ...... 221 218C—Breeton sandy loam, 2 to 8 percent 220D—Amor-Work complex, 8 to 15 percent slopes ...... 220 slopes ...... 221 218D—Breeton sandy loam, 8 to 15 percent 457D—Arrowpeak-Gilispie-Fifer complex, 2 to 15 slopes ...... 220 percent slopes ...... 323 435C—Bridger clay loam, 2 to 8 percent 353F—Ashbon-Rock outcrop-Winkler complex, slopes ...... 312 35 to 60 percent slopes ...... 266 424C—Bridger, very stony-Adel complex, 2 to 8 343F—Ashbon-Winkler-Rock outcrop complex, percent slopes ...... 306 35 to 60 percent slopes ...... 259 xv

424E—Bridger, very stony-Adel complex, 155E—Cabbart-Delpoint loams, moist, 15 to 35 8 to 35 percent slopes ...... 307 percent slopes ...... 196 210E—Cabba loam, 15 to 35 percent slopes ...... 217 112E—Cabbart-Delpoint, calcareous loams, 210D—Cabba loam, 2 to 15 percent slopes ...... 217 15 to 35 percent slopes ...... 178 398F—Cabba very cobbly loam, 15 to 60 112C—Cabbart-Delpoint, calcareous, loams, percent slopes ...... 291 2 to 8 percent slopes ...... 177 227F—Cabba, moist-Rock outcrop complex, 112D—Cabbart-Delpoint, calcareous, loams, 15 to 60 percent slopes ...... 224 8 to 15 percent slopes ...... 178 413E—Cabba-Bowery complex, 2 to 60 percent 138D—Cabbart-Megonot-Kobase clay loams, slopes ...... 300 2 to 15 percent slopes ...... 185 208F—Cabba-Castner complex, 15 to 60 375D—Cabbart-Rentsac, moist, complex, percent slopes ...... 216 2 to 15 percent slopes ...... 280 335D—Cabba-Castner-Amherst complex, 116F—Cabbart-Rock outcrop complex, 15 to 60 2 to 15 percent slopes ...... 257 percent slopes ...... 179 403F—Cabba-Castner-Rock outcrop complex, 117C—Cabbart-Tanna complex, 2 to 8 percent moist, 25 to 60 percent slopes ...... 293 slopes ...... 180 437E—Cabba-Castner-Work complex, 4 to 35 357E—Cabba-Vershal complex, 15 to 45 percent slopes, bouldery ...... 313 percent slopes ...... 269 307E—Cabba-Doney loams, 8 to 35 percent 357D—Cabba-Vershal complex, 4 to 15 percent slopes ...... 251 slopes ...... 268 179F—Cabba-Rock outcrop complex, 15 to 60 181C—Cabba-Winifred clay loams, 2 to 8 percent slopes ...... 203 percent slopes ...... 204 110E—Cabbart loam, 15 to 35 percent slopes .... 177 181D—Cabba-Winifred clay loams, 8 to 15 110D—Cabbart loam, 2 to 15 percent slopes ...... 177 percent slopes ...... 204 374F—Cabbart, moist-Delpoint-Rock outcrop 186E—Castner channery loam, 15 to 35 complex, 15 to 45 percent slopes ...... 279 percent slopes ...... 208 157F—Cabbart, moist-Delpoint-Rock outcrop 186D—Castner channery loam, 2 to 15 percent complex, 15 to 60 percent slopes ...... 197 slopes ...... 208 151C—Cabbart-Boxwell loams, 2 to 8 percent 202E—Castner-Absarokee complex, 15 to 35 slopes ...... 193 percent slopes ...... 214 151D—Cabbart-Boxwell loams, 8 to 15 percent 202C—Castner-Absarokee complex, 2 to 8 slopes ...... 194 percent slopes ...... 213 148E—Cabbart-Cambeth complex, 4 to 35 202D—Castner-Absarokee complex, 8 to 15 percent slopes ...... 192 percent slopes ...... 214 139E—Cabbart-Delpoint loams, 15 to 35 372E—Castner-Amherst complex, 15 to 35 percent slopes ...... 187 percent slopes ...... 278 139C—Cabbart-Delpoint loams, 2 to 8 percent 372D—Castner-Amherst complex, 2 to 15 slopes ...... 186 percent slopes ...... 278 139D—Cabbart-Delpoint loams, 8 to 15 percent 191C—Castner-Farnuf complex, 2 to 8 percent slopes ...... 186 slopes ...... 209 xvi

397F—Castner-Laceycreek-Bowery complex, 406E—Doney-Macar loams, 4 to 25 percent 25 to 60 percent slopes ...... 290 slopes ...... 295 397E—Castner-Laceycreek-Bowery complex, 392E—Doney-Vershal complex, 8 to 35 percent 8 to 25 percent slopes ...... 290 slopes ...... 287 350F—Castner-Mowbray-Rock outcrop 381E—Duckcreek-Arrowpeak complex, 8 to 45 complex, 25 to 60 percent slopes ...... 264 percent slopes ...... 282 178F—Castner-Roy complex, 15 to 60 percent 146B—Ethridge clay loam, 1 to 4 percent slopes ...... 203 slopes ...... 190 192D—Castner-Shambo complex, 8 to 15 146C—Ethridge clay loam, 4 to 8 percent percent slopes ...... 210 slopes ...... 191 283F—Castner-Wayden complex, moist, 153C—Ethridge-Reedpoint complex, 2 to 8 15 to 60 percent slopes ...... 245 percent slopes ...... 194 349D—Cheadle channery loam, 2 to 15 153D—Ethridge-Reedpoint complex, 8 to 15 percent slopes ...... 264 percent slopes ...... 195 347E—Cheadle-Lymanson-Gilispie complex, 169C—Ethridge-Tanna clay loams, 2 to 8 15 to 35 percent slopes ...... 262 percent slopes ...... 200 347D—Cheadle-Lymanson-Gilispie complex, 144B—Evanston loam, 0 to 4 percent slopes ...... 189 2 to 15 percent slopes ...... 262 144C—Evanston loam, 4 to 8 percent slopes ...... 189 168D—Chinook fine sandy loam, 8 to 15 percent 144D—Evanston loam, 8 to 15 percent slopes ...... 200 slopes ...... 190 376E—Chinook-Twilight fine sandy loams, 154E—Evanston-Reedpoint complex, 8 to 35 8 to 25 percent slopes ...... 280 percent slopes ...... 195 216A—Clunton clay loam, 0 to 2 percent 445C—Evanston-Tanna complex, 2 to 8 percent slopes ...... 219 slopes ...... 318 361E—Cowood very channery loam, 4 to 25 209C—Fairfield gravelly loam, 2 to 8 percent percent slopes ...... 271 slopes ...... 216 407F—Danaher-Timberlin complex, 25 to 60 209D—Fairfield gravelly loam, 8 to 15 percent percent slopes ...... 296 slopes ...... 216 190C—Danvers gravelly clay loam, 2 to 8 135A—Fairway loam, 0 to 2 percent slopes ...... 185 percent slopes ...... 209 439B—Fairway-Korchea loams, channeled, 269C—Danvers loam, 2 to 8 percent slopes ...... 239 0 to 4 percent slopes ...... 314 DA—Denied access ...... 325 230B—Farnuf loam, 0 to 4 percent slopes...... 225 204A—Dimmick silty clay, 0 to 2 percent 230C—Farnuf loam, 4 to 8 percent slopes ...... 226 slopes ...... 215 230D—Farnuf loam, 8 to 15 percent slopes ...... 226 231C—Doney-Cabba loams, 2 to 8 percent 346E—Farnuf-Reedwest-Shawmut complex, slopes ...... 226 15 to 35 percent slopes ...... 261 231D—Doney-Cabba loams, 8 to 15 percent 193C—Farnuf-Winifred complex, 2 to 8 percent slopes ...... 227 slopes ...... 210 355F—Doney-Cabba, moist loams, 35 to 60 384E—Fifer-Cheadle complex, 15 to 45 percent percent slopes ...... 267 slopes ...... 284 xvii

359F—Fifer-Cheadle-Monaberg complex, 276A—Larry clay loam, 0 to 2 percent slopes ..... 242 25 to 60 percent slopes ...... 270 102B—Ledger family, clay loam, 1 to 4 percent 382E—Fifer-Knep complex, 15 to 45 percent slopes ...... 174 slopes ...... 283 453E—Libeg very cobbly sandy loam, 15 to 35 383D—Fifer-Rock outcrop complex, 4 to 15 percent slopes ...... 321 percent slopes ...... 283 453D—Libeg very cobbly sandy loam, 2 to 15 460B—Foolhen-Beehive-Bearmouth complex, percent slopes ...... 321 0 to 4 percent slopes ...... 324 414D—Libeg, extremely bouldery-Adel complex, 447B—Frenchcreek very gravelly loam, 2 to 4 4 to 15 percent slopes ...... 301 percent slopes ...... 318 414F—Libeg-Libeg, extremely bouldery-Adel 170C—Gerdrum-Creed complex, 0 to 8 percent complex, 15 to 60 percent slopes ...... 301 slopes ...... 201 188C—Linwell clay loam, 2 to 8 percent 370D—Greybear-Rentsac complex, 2 to 15 slopes ...... 209 percent slopes ...... 277 194C—Linwell-Amor complex, 2 to 8 percent 103A—Havre loam, 0 to 2 percent slopes ...... 175 slopes ...... 211 118C—Hinterland clay loam, 0 to 8 percent 245C—Lonna silt loam, 2 to 8 percent slopes ..... 231 slopes ...... 180 348E—Lymanson-Cheadle-Adel complex, 206D—Hinterland-Rentsac-Cabbart complex, 8 to 35 percent slopes ...... 263 2 to 15 percent slopes ...... 215 404F—Lymanson-Doby-Rock outcrop complex, 219A—Klayent clay loam, 0 to 2 percent 15 to 60 percent slopes ...... 294 slopes ...... 220 215D—Macar loam, 8 to 15 percent slopes...... 219 360D—Knep family-Warwood loams, 4 to 15 215B—Macar loam, calcareous surface, 0 to 4 percent slopes ...... 270 percent slopes ...... 218 150C—Kobase clay loam, 2 to 8 percent 215C—Macar loam, calcareous surface, 4 to 8 slopes ...... 193 percent slopes ...... 218 150D—Kobase clay loam, 8 to 15 percent 159A—Marcott cobbly clay loam, 0 to 2 percent slopes ...... 193 slopes ...... 197 363E—Kobase-Rentsac-Megonot complex, 277B—Marcott-Larry complex, 0 to 4 percent 4 to 25 percent slopes ...... 272 slopes ...... 243 217A—Korchea loam, 0 to 2 percent slopes ...... 219 127C—Marmarth loam, 2 to 8 percent slopes ..... 181 213A—Korchea-Fairway-Albicalis loams, 141C—Marmarth-Cabbart loams, 2 to 8 percent channeled, 0 to 4 percent slopes ...... 217 slopes ...... 188 147B—Kremlin loam, 0 to 4 percent slopes...... 191 141D—Marmarth-Cabbart loams, 8 to 15 147C—Kremlin loam, 4 to 8 percent slopes ...... 191 percent slopes ...... 188 147D—Kremlin loam, 8 to 15 percent slopes ...... 192 440C—Marmarth-Rentsac complex, 2 to 8 250A—Lallie family, silty clay, 0 to 2 percent percent slopes ...... 314 slopes ...... 231 440D—Marmarth-Rentsac complex, 8 to 15 412F—Lap-Winspect complex, 35 to 70 percent percent slopes ...... 315 slopes ...... 300 161B—Martinsdale gravelly loam, 0 to 4 percent 412E—Lap-Winspect-Rock outcrop complex, slopes ...... 198 8 to 35 percent slopes ...... 299 xviii

161C—Martinsdale gravelly loam, 4 to 8 percent 411E—Pianohill-Whitlash-Adel complex, slopes ...... 198 15 to 45 percent slopes ...... 299 104A—Meadowcreek loam, 0 to 2 percent 425E—Pintlar-Bridger loams, 4 to 35 percent slopes ...... 175 slopes ...... 307 109A—Meadowcreek-Nesda loams, 0 to 2 251B—Radersburg gravelly loam, 0 to 4 percent percent slopes ...... 176 slopes ...... 232 308C—Meagher gravelly loam, 2 to 8 percent 356D—Redchief gravelly loam, 4 to 15 percent slopes ...... 251 slopes ...... 268 365C—Megonot-Cabbart complex, 2 to 8 449E—Redchief very stony loam, 15 to 35 percent slopes ...... 273 percent slopes ...... 319 417B—Melville cobbly loam, 0 to 4 percent 434F—Redchief-Arrowpeak, moist complex, slopes ...... 303 15 to 60 percent slopes ...... 311 378D—Melville cobbly loam, 2 to 15 percent 452D—Redchief-Melville complex, 4 to 15 slopes, stony ...... 282 percent slopes ...... 320 418D—Melville cobbly loam, 4 to 15 percent 455F—Redfern-Fifer complex, 25 to 60 percent slopes ...... 303 slopes ...... 322 409F—Merino-Elve-Rock outcrop complex, 454F—Redfern-Warwood complex, 25 to 70 25 to 80 percent slopes ...... 297 percent slopes ...... 321 386D—Millerlake loam, 4 to 15 percent slopes ... 285 131F—Reedpoint very channery loam, 15 to 60 385E—Millerlake-Arrowpeak-Adel complex, percent slopes ...... 183 8 to 35 percent slopes ...... 284 131D—Reedpoint very channery loam, 2 to 15 433D—Monaberg loam, 4 to 15 percent percent slopes ...... 183 slopes ...... 311 176C—Reedwest-Cabba loams, 2 to 8 percent 430E—Mowbray-Bridger-Novary complex, slopes ...... 202 0 to 35 percent slopes ...... 309 399F—Reedwest-Cabba-Castner complex, 107A—Nesda-McIlwaine loams, 0 to 2 percent 15 to 60 percent slopes ...... 291 slopes ...... 176 253E—Reedwest-Castner complex, 15 to 35 100B—Nesda-Meadowcreek-Clunton loams, percent slopes ...... 233 0 to 4 percent slopes ...... 174 253C—Reedwest-Castner complex, 2 to 8 459A—Newtman muck, 0 to 2 percent slopes ..... 324 percent slopes ...... 232 275B—Overfelt clay loam, 0 to 4 percent 253D—Reedwest-Castner complex, 8 to 15 slopes ...... 242 percent slopes ...... 233 268B—Overfelt-Roy complex, 0 to 4 percent 402F—Reedwest-Rock outcrop complex, slopes ...... 239 15 to 60 percent slopes, very stony ...... 293 278B—Perma gravelly loam, 0 to 4 percent 451F—Rentsac-Radersburg complex, 15 to 60 slopes ...... 243 percent slopes ...... 320 278C—Perma gravelly loam, 4 to 8 percent 367E—Rentsac-Reedpoint complex, 15 to 35 slopes ...... 243 percent slopes ...... 275 352E—Perma-Rock outcrop complex, 15 to 45 367D—Rentsac-Reedpoint complex, 2 to 15 percent slopes ...... 266 percent slopes ...... 274 xix

369E—Rentsac-Tanna complex, 15 to 35 224C—Shambo loam, 4 to 8 percent slopes ...... 222 percent slopes ...... 276 224D—Shambo loam, 8 to 15 percent slopes ..... 223 369D—Rentsac-Tanna complex, 2 to 15 percent 284C—Shawmut gravelly loam, 2 to 8 percent slopes ...... 276 slopes ...... 245 368E—Rentsac-Tanna-Rock outcrop complex, 284D—Shawmut gravelly loam, 8 to 15 percent 8 to 35 percent slopes ...... 275 slopes ...... 246 166B—Richey silty clay, 0 to 4 percent slopes .... 199 281F—Shawmut-Castner complex, 15 to 60 166C—Richey silty clay, 4 to 8 percent slopes .... 199 percent slopes ...... 244 415F—Rocko-Adel complex, 15 to 45 percent 333F—Shawmut-Castner-Rock outcrop complex, slopes ...... 302 15 to 60 percent slopes ...... 256 401B—Roy cobbly loam, 0 to 4 percent slopes ... 293 304C—Shawmut-Shambo complex, 2 to 8 182C—Roy gravelly clay loam, 2 to 8 percent percent slopes ...... 250 slopes ...... 205 304D—Shawmut-Shambo complex, 8 to 15 182D—Roy gravelly clay loam, 8 to 15 percent percent slopes ...... 250 slopes ...... 205 450D—Sieben gravelly loam, 2 to 15 percent 294B—Roy gravelly loam, 0 to 4 percent slopes ...... 319 slopes ...... 248 443B—Sieben-Attewan gravelly loams, 0 to 4 311C—Roy, extremely stony-Turner complex, percent slopes ...... 316 2 to 8 percent slopes ...... 252 336E—Sinnigam-Wayden complex, moist, 252B—Roy-Swampcreek complex, 0 to 4 15 to 45 percent slopes ...... 257 percent slopes ...... 232 239C—Sixbeacon gravelly loam, 2 to 8 percent 313C—Roy-Tamaneen complex, 2 to 8 percent slopes ...... 230 slopes ...... 254 256F—Sixbeacon-Reedpoint complex, 15 to 60 295B—Roy-Turner complex, 0 to 4 percent percent slopes ...... 235 slopes ...... 248 249B—Soapcreek clay loam, 0 to 2 percent 265C—Sagedale clay loam, 2 to 8 percent slopes ...... 231 slopes ...... 237 461B—Soapcreek-Absher family complex, 265D—Sagedale clay loam, 8 to 15 percent 0 to 4 percent slopes ...... 325 slopes ...... 238 396C—Soapcreek-Lallie family complex, 0 to 8 238C—Sagedale-Cabba complex, 2 to 8 percent slopes ...... 289 percent slopes ...... 229 456F—Stemple-Cheadle, moist, complex, 238F—Sagedale-Cabba complex, 8 to 35 25 to 70 percent slopes ...... 322 percent slopes ...... 229 426F—Stemple-Worock complex, 35 to 70 421E—Sawicki, extremely bouldery-Bowery percent slopes, very stony ...... 308 complex, 4 to 25 percent slopes ...... 305 289A—Swampcreek gravelly sandy clay loam, 279C—Shambo clay loam, calcareous, 4 to 8 0 to 2 percent slopes ...... 247 percent slopes ...... 244 174C—Sweetgrass clay loam, 2 to 8 percent 189C—Shambo gravelly clay loam, 2 to 8 slopes ...... 202 percent slopes ...... 209 266B—Sweetgrass clay, 0 to 4 percent 224B—Shambo loam, 0 to 4 percent slopes ...... 222 slopes ...... 238 xx

271B—Sweetgrass gravelly loam, 0 to 4 percent 309E—Ticell-Amor loams, 8 to 35 percent slopes ...... 240 slopes ...... 251 183B—Tamaneen clay loam, 0 to 4 percent 373D—Ticell-Castner complex, 2 to 15 percent slopes ...... 206 slopes ...... 279 183C—Tamaneen gravelly clay loam, 2 to 8 379F—Tongue River-Arrowpeak, moist complex, percent slopes ...... 206 15 to 60 percent slopes ...... 282 183A—Tamaneen gravelly loam, 0 to 2 percent 377F—Tongue River-Cabba, moist-Adel loams, slopes ...... 206 15 to 60 percent slopes ...... 281 142C—Tanna clay loam, 2 to 8 percent slopes ... 189 358E—Tongue River-Danaher loams, 15 to 35 366C—Tanna, calcareous,-Rentsac complex, percent slopes ...... 269 2 to 8 percent slopes ...... 273 405F—Tongue River-Doby-Rock outcrop 366D—Tanna, calcareous,-Rentsac complex, complex, 15 to 60 percent slopes ...... 295 8 to 15 percent slopes ...... 274 387E—Tongue River-Novary-Cowood complex, 172C—Tanna-Boxwell, calcareous, complex, 4 to 45 percent slopes ...... 285 2 to 8 percent slopes ...... 201 391F—Tongue River-Timberlin complex, 172D—Tanna-Boxwell, calcareous, complex, 35 to 60 percent slopes ...... 286 8 to 15 percent slopes ...... 202 288B—Turner sandy clay loam, 0 to 4 percent 129C—Tanna-Cabbart complex, 2 to 8 percent slopes ...... 246 slopes ...... 181 156C—Twilight-Blacksheep fine sandy loams, 129D—Tanna-Cabbart complex, 8 to 15 percent 2 to 8 percent slopes ...... 196 slopes ...... 182 458C—Vebar-Castner complex, 2 to 8 percent 130C—Tanna-Hinterland clay loams, 2 to 8 slopes ...... 323 percent slopes ...... 182 312F—Vershal very channery loam, 15 to 60 130D—Tanna-Hinterland clay loams, 8 to 15 percent slopes ...... 253 percent slopes ...... 183 312D—Vershal very channery loam, 2 to 15 442C—Tanna-Yawdim complex, 2 to 8 percent percent slopes ...... 253 slopes ...... 316 393E—Vershal-Reedwest complex, 8 to 35 106B—Thibadeau loam, channeled, saline, percent slopes ...... 287 0 to 4 percent slopes ...... 175 236B—Verson loam, 0 to 4 percent slopes...... 228 237B—Thibadeau loam, saline, 0 to 4 percent 236C—Verson loam, 4 to 8 percent slopes ...... 228 slopes ...... 229 344F—Vision-Sweetweed-Whitlash complex, 255B—Thibadeau, saline-Absher family 25 to 60 percent slopes ...... 260 complex, 0 to 8 percent slopes ...... 234 354F—Vision-Whitlash-Rock outcrop complex, 420E—Tibson, extremely bouldery-Bridger, 35 to 60 percent slopes ...... 267 extremely bouldery-Adel complex, 8 to 35 408F—Warwood-Timberlin-Cowood complex, percent slopes ...... 304 35 to 60 percent slopes ...... 297 428F—Tibson-Whitore-Rock outcrop complex, 408E—Warwood-Timberlin-Cowood complex, 35 to 70 percent slopes ...... 308 8 to 35 percent slopes ...... 296 332E—Ticell loam, 15 to 35 percent slopes ...... 256 W—Water ...... 326 332D—Ticell loam, 2 to 15 percent slopes ...... 255 xxi

M-W—Water, miscellaneous ...... 326 419E—Winspect-Work-Bowery, 8 to 35 percent 259D—Wayden clay, 2 to 15 percent slopes ...... 236 slopes, extremely bouldery ...... 303 432E—Wayden-Amherst-Winifred complex, 274B—Work clay loam, 0 to 4 percent slopes ..... 241 8 to 45 percent slopes ...... 310 274E—Work clay loam, 15 to 35 percent 331F—Wayden-Castner complex, 15 to 60 slopes ...... 242 percent slopes ...... 255 274C—Work clay loam, 4 to 8 percent slopes ..... 241 438F—Wayden-Castner complex, 15 to 60 274D—Work clay loam, 8 to 15 percent slopes ... 241 percent slopes, bouldery ...... 313 337C—Work gravelly clay loam, 2 to 8 percent 262D—Wayden-Castner-Cabba complex, slopes ...... 258 2 to 15 percent slopes ...... 237 337D—Work gravelly clay loam, 8 to 15 percent 362F—Wayden-Castner-Rock outcrop complex, slopes ...... 258 25 to 60 percent slopes ...... 271 232B—Work loam, 0 to 4 percent slopes ...... 227 260C—Wayden-Doney complex, 2 to 8 percent 232C—Work loam, 4 to 8 percent slopes ...... 228 slopes ...... 236 422C—Work, stony-Bowery complex, 2 to 8 286F—Wayden-Rock outcrop complex, 15 to 60 percent slopes ...... 305 percent slopes ...... 246 422E—Work, very stony-Bowery complex, 345E—Weedzunit-Ashbon complex, 15 to 45 8 to 35 percent slopes ...... 306 percent slopes ...... 261 197C—Work-Castner complex, 2 to 8 percent 345D—Weedzunit-Ashbon complex, 4 to 15 slopes ...... 212 percent slopes ...... 260 197D—Work-Castner complex, 8 to 15 percent 371E—Whitlash cobbly sandy loam, 15 to 35 slopes ...... 212 percent slopes ...... 278 429E—Work-Roy, bouldery-Bigsag family 371D—Whitlash cobbly sandy loam, 2 to 15 complex, 2 to 35 percent slopes ...... 309 percent slopes ...... 277 134B—Yamacall loam, 1 to 4 percent slopes ...... 184 394D—Whitlash-Beenom complex, 4 to 15 134C—Yamacall loam, 4 to 8 percent slopes ...... 184 percent slopes ...... 288 134D—Yamacall loam, 8 to 15 percent slopes .... 184 395E—Whitlash-Beenom-Bacbuster complex, 196B—Yamacall-Bigsag family complex, 0 to 4 8 to 25 percent slopes ...... 289 percent slopes ...... 211 351E—Whitlash-Pianohill complex, 15 to 35 241D—Yawdim clay loam, 2 to 15 percent percent slopes ...... 265 slopes ...... 230 351D—Whitlash-Pianohill complex, 4 to 15 167F—Yawdim-Birney-Rock outcrop complex, percent slopes ...... 265 15 to 60 percent slopes ...... 199 254C—Winifred clay loam, 2 to 8 percent 441D—Yawdim-Delpoint complex, 2 to 15 slopes ...... 234 percent slopes ...... 315 303D—Winspect cobbly loam, 4 to 15 percent 140F—Yawdim-Rentsac complex, 15 to 60 slopes ...... 249 percent slopes ...... 187 303E—Winspect very cobbly loam, 15 to 35 115D—Yawdim-Rentsac-Cabbart complex, percent slopes ...... 249 2 to 15 percent slopes ...... 179 310E—Winspect-Ticell complex, 15 to 35 201F—Yawdim-Rock outcrop complex, 15 to 60 percent slopes ...... 252 percent slopes ...... 213 xxii

Summary of Tables

Temperature and precipitation ...... 14

Freeze dates in spring and fall ...... 15

Growing season ...... 16

For tables with the most current data, please visit the Soil Data Mart at http://soildatamart.nrcs.usda.gov/. xxv

Foreword

This soil survey contains information that affects land use planning in this survey area. It contains predictions of soil behavior for selected land uses. The survey also highlights limitations and hazards inherent in the soil. 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 management needed 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 proper performance. Conservationists, teachers, students, and specialists in recreation, wildlife management, waste disposal, and pollution control can use the survey to help them understand, protect, and enhance the environment. Various land use regulations of Federal, State, and local governments may impose special restrictions on land use or land treatment. The information in this report is intended to identify soil properties that are used in making various land use or land treatment decisions. Statements made in this report are intended to help the land users identify and reduce the effects of soil limitations on various land uses. The landowner or user is responsible for identifying and complying with existing laws and regulations. Great differences in soil properties can occur within short distances. Some soils are seasonally wet or subject to flooding. Some are shallow to bedrock. Some are too unstable to be used as a foundation for buildings or roads. Clayey or wet soils are poorly suited to use as septic tank absorption fields. A high water table makes a soil poorly suited to basements or underground installations. These and many other soil properties that affect land use are described in this soil survey. The location of each soil 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 and additional information are available at local offices of the Natural Resources Conservation Service or the Cooperative Extension Service.

Dave White State Conservationist Natural Resources Conservation Service 1

Soil Survey of Sweet Grass County Area, Montana

By Daniel R. Shurtliff, Project Leader, Natural Resources Conservation Service

Fieldwork by Charles C. French, T. Roxann Lincoln, Robert D. Logar, Daniel R. Shurtliff, and Eve Wills, Natural Resources Conservation Service

United States Department of Agriculture, Natural Resources Conservation Service, in cooperation with the Montana Agricultural Experiment Station

SWEET GRASS COUNTY AREA is located in south- central Montana (fig. 1). The county has an area of about 1,224,166 acres, or 1,912 square miles, of which about 904,100 acres, or 1,412 square miles, is included in the soil survey. The soil survey area is bounded by the Gallatin National Forest on the south and northwest, Park County on the west, Wheatland County on the north, Golden Valley County on the northeast, and Stillwater County on the east. Big Timber, the centrally located county seat and principal town, lies at the confluence of the Yellowstone and Boulder Rivers. In 2000, Sweet Grass County’s population was 3,609. The Sweet Grass County Area lies where the Figure 1.—Location of Sweet Grass County Area, Montana Missouri Plateau of the Great Plains physiographic province is met by the Middle Rocky Mountains and Northern Rocky Mountains physiographic provinces General Nature of the Survey Area (Smith, 1983). The surface features of the county are largely the result of cretaceous marine sedimentation This section describes some of the environmental and cretaceous and tertiary igneous intrusion and and cultural features that affect the use and volcaniclastic sedimentation and cretaceous and management of soils in the survey area. These tertiary folding and faulting. Erosion has altered these features are history and development; industry, features and has helped produce major stream transportation, and recreation; natural resources; valleys, including the Yellowstone River valley. Most of physiography, drainage, and geology; mining; oil, gas, the survey area is drained by the Yellowstone River. and coal; geothermal resources; ground-water The extreme northern portion of the county is drained resources; seismicity; and climate. by the Musselshell River. This soil survey supersedes the Soils of Sweet History and Development Grass County, Soil Reconnaissance of Montana, Preliminary Report (Montana State College, 1956). It The area that now includes Sweet Grass County provides additional information and has larger maps, was inhabited by the Crow and Blackfeet Nations which show the soils in greater detail. prior to settlement by immigrants. 2 Soil Survey

The Lewis and Clark Expedition brought the first- Industry, Transportation, and Recreation known visitors of European descent into the area. In 1806 on his return from the Pacific Coast, Captain Since Sweet Grass County was established, William Clark camped along the Yellowstone River ranching has been a major part of the economy. In near its confluence with the Boulder River and Big 1993, there were 41,600 cattle, 19,100 sheep, and Timber Creek, near the present-day town of Big 4,600 hogs on farms and ranches. Cultivated Timber. Clark named Big Timber Creek for the large agricultural land totaled 61,000 acres. Approximately cottonwood trees growing at its mouth. From 1806 to 37,500 acres of this land was irrigated. Irrigated 1850, the only explorers to venture into the area were cropland is located near major river and stream hunters, trappers, and Indian traders. valleys. Water for irrigation comes principally from In 1867, the first treaty fort was built in the Sweet canals, with water diverted from rivers and streams. Grass County area at the mouth of Otter Creek. In Upper and Lower Glasston Lakes also are sources of 1869, the area was included in the first Crow Indian water for irrigation. Alfalfa hay is the principal irrigated Reservation. crop, while wheat and barley are the principal dryland In the late 1860s, the first trail herds from Texas crops. Dryland cropland is mainly located in the began coming into the area. The decade from 1870 northeastern part of the county. to 1880 was the boom of the cattle industry, the Some light industry is located in Big Timber. The range wars, and the “Wars for the West.” The early town has an industrial park where small assembly cattle companies were large and grazed their cattle plants and specialty firearm factories are located. on the open range. Prior to the turn of the century, A major platinum-palladium mine is located south the public domain was controlled by stockmen and of Big Timber on the East Boulder River. early miners until homesteader settlement and the About 25 percent of the county is forested. Timber establishment of the Forest Reserve System is a minor industry in the county because much of the effectively closed the open range. forested land does not support commercial-grade The early 1880s brought the railroad into Sweet timber. There are two small sawmills that produce a Grass County and the population of the area grew small amount of dimensional lumber, rough lumber, and prospered. The town of Big Timber was posts, and poles. established and for a short time became the largest Interstate 90 runs east and west across the county wool-shipping center in the United States. along the Yellowstone River. U.S. Highway 191 Mining played an important role in the early extends north from Big Timber to Melville and through development of the county. In the 1890s, the to the Wheatland County line. County Road 298 Independence Mining Company was established begins at Big Timber and extends south through in the Upper Boulder River valley. Eventually the McLeod to the Park County line. An extensive camp supported between 400 and 500 miners. network of secondary roads provides corridors Mining continues to play an important role in the through the area. Montana Rail Link has a rail line regional economy due to the presence of a major that parallels the Yellowstone River. A public airport is platinum-palladium deposit in the southern part of maintained at Big Timber. The nearest commercial the county. airline facilities are at Billings in Yellowstone County The Homestead Act brought scores of settlers, and at Belgrade in Gallatin County, between 75 and many from Minnesota, into the area between 1890 85 miles distant. and 1910. The Melville community was established The area’s wilderness and natural scenic beauty, at this time. The majority of settlers were of coupled with opportunities for outdoor recreation, Norwegian descent. The settlers plowed up the have increased the importance of tourism in some prairie and planted it to wheat and other small grains. parts of the county. The survey area borders the Around 1911, the state’s first dude ranch was Absaroka-Beartooth Mountains in the southern part established in the eastern foothills of the Crazy of the county and the Crazy Mountains in the Mountains. Dude ranching has remained an northwestern part. Outdoor recreational opportunities important industry in the county. are abundant. Dude ranches, campgrounds, hiking From the 1920s until the present, the county has and packing trails, and snowmobile trails are progressed with developments in technology. Today, available. Fishing and hunting are also attractions to agriculture is the principal industry. Most of the land the area with outfitting and guiding services providing is used for livestock grazing. seasonal employment for many residents. Sweet Grass County Area, Montana—Part I 3

Natural Resources mountain ranges. The easternmost end of the Crazy Mountains extends from Park and Meagher Counties The most important natural resource in this survey into the northwestern corner of Sweet Grass County. area is the soil. Sweet Grass County consists of South of the Yellowstone River, the Beartooth about 67 percent rangeland, 7 percent cropland, and Mountains occupy most of the southern part of the 26 percent forestland. county. Natural sources of water include springs, ponds, The Beartooth Mountains extend 75 miles creeks, and rivers. Sweet Grass County has two (120 km) from Livingston, on the northwest, to rivers, the Yellowstone and the Boulder, and Red Lodge, on the southeast. Geologically, the numerous creeks flowing through it. The rivers and Beartooth Mountains are subdivided into three creeks are used heavily for irrigation water. Many separate blocks based on their structure and springs have been developed for livestock use. lithology. The soil survey area extends only into the Within the county, there are two reservoirs—Upper tip of the northernmost North Snowy Block, which Glasston and Lower Glasston Lakes. They are used is composed of Paleozoic-aged sedimentary rocks for recreation and irrigation-water management. with Precambrian granitic rocks further to the south. There are no known coal-, oil-, or gasfields that are The South Snowy Block, which occupies the being developed within Sweet Grass County. There southwestern portion of the Beartooth Mountains, is are some coal and geothermal areas in the southern composed of Precambrian granitic rocks overlain by part of the county that may have the potential to be Tertiary volcanic rocks. The Beartooth Block occupies developed. the larger, southeastern portion of the Beartooth Gold, silver, chromium, platinum, palladium, Mountains and is composed of Precambrian granitic copper, nickel, and zinc were all actively mined in the rocks. This latter block is also referred to as the past. These deposits are located in the Crazy and Beartooth Plateau. The Absaroka Range is an Beartooth Mountains. Gold, silver, and chromium are adjacent feature, which extends from Gardiner into still actively mined on a small scale. The western end northwestern Wyoming, consisting of the Yellowstone of the Stillwater Complex and the contained platinum, Plateau volcanics. palladium, copper, and nickel resources are found in Not all of Sweet Grass County was included in the the southeastern part of the county. This deposit is soil survey area. The areas excluded are the portions being developed at this time. of the Crazy and Beartooth Mountains owned by the Sand and gravel deposits are plentiful. There are U.S. Forest Service. South of the Yellowstone River, several small sand and gravel operations throughout the soil survey area extends up the Boulder River to the county. the McLeod Basin, ending at Green and Baker Mountains. The soil survey area can be divided into three Physiography, Drainage, and Geology distinct physiographic units with similar topography. Marie V. Marshall, Montana State Geologist, Natural Resources South of the Yellowstone River, the topography is Conservation Service, prepared this section. mountainous and rugged, with significant relief. The area north of the Yellowstone River, excluding the Crazy Mountains, is composed of gentler, hilly Physiography topography. The Cayuse Hills in the northeastern Sweet Grass County lies in a complicated corner of the county are a distinctive series of ridges structural setting at the intersection of three major which dip gently to the southeast along the dip of the physiographic provinces. They are the Northern beds. Rocky Mountain Province, which includes the Crazy Within the county, elevations range from 3,755 feet Mountains; the Middle Rocky Mountain Province, (1,145 m) above sea level where the Yellowstone which includes the Beartooth Mountains; and the River flows out of the county, to a high of Unglaciated Missouri Plateau of the Great Plains approximately 11,230 feet (3,423 m) at the summit Province, which extends to the east from the of Crazy Peak. High peaks in the Crazy Mountains mountains. have elevations between 9,000 and 11,000 feet The Yellowstone River flows from west to east, (2,740 and 3,355 m). Typical elevations of the bisecting the county. The county contains parts of two high peaks in the Absaroka Range are between 4 Soil Survey

10,000 and 11,500 feet (3,048 and 3,505 m). The into a featureless land surface, or peneplain, near East Boulder and Lake Plateaus have average sea level. elevations above 9,000 feet (2,743 m). For much of Paleozoic time, most of Montana was Within the soil survey area the highest point is the slightly below sea level and covered by warm, summit of Green Mountain, which has an elevation of shallow seas. Thick sequences of sediments were 7,337 feet (2,236 m). Big Timber has an elevation of deposited on coastal plains and the shallow sea floor approximately 4,480 feet (1,365 m). during alternating periods of rising and falling sea levels. In this area, the accumulation of sedimentary Drainage rocks is estimated to be nearly 4,000-feet (1,220-m) Most of the county is drained by the Yellowstone thick. River and its tributaries. The relatively small area Sandstone was deposited in beach and near- northeast of the Cayuse Hills drains to the shore environments; shale was deposited in lower Musselshell River. The Crazy Mountains are drained energy, deep-water environments; and limestone was by a number of small, radiating streams which flow normally formed in warm, shallow water. The rock into the Yellowstone River between Springdale and types grade both laterally and vertically into each Big Timber. Approximately half of these tributaries are other, and their thicknesses are not consistent across intermittent. large areas. Organic matter, which was buried in the Major tributaries of the Yellowstone River include, marine sediments, was eventually converted to oil from west to east, Big Timber Creek, which joins the and gas. Yellowstone River from the north at Big Timber; the Sea level fluctuations across Montana continued Boulder River, which joins the Yellowstone River from throughout the Mesozoic Era. This was the time of the the south at Big Timber; Sweet Grass Creek which dinosaur. The shoreline moved back and forth across joins the Yellowstone River near Greycliff; and Bridger the nearly flat region. As it shifted, it created a Creek which joins the Yellowstone River near the complex interfingering pattern of sand and mud that eastern border of the county. The Yellowstone Valley was deposited along rivers, lakes, deltas, and coastal is flat and wide throughout most of the county, plains. Mesozoic sediments also contain coal, oil, and ranging from 1 to 2 miles (1.6 to 3.2 km) in width. gas. Downstream of its confluence with Bridger Creek, the In the Late Cretaceous Period, a collision 1 Yellowstone River narrows to between /2 and 1 mile between major tectonic plates to the west created in width. There are no dams in the county on the compressional forces that formed the Rocky Yellowstone River or any of its major tributaries. Mountains. This regional northeast-southwest compression resulted in large-scale folding and Geologic History and Regional Geology faulting and is known as the Laramide Orogeny. The geologic history of Sweet Grass County Mountain-building activity at this time created the began as the earth’s crust cooled in the Archean Eon prominent structural features that exist today, of the Precambrian Age. Geologists believe that the including the downwarping of the Crazy Mountains earth was formed approximately 4.5 billion years ago. Basin. As the mountains rose, rivers extended to the In the vast amount of geologic time that has passed east and deposited enormous volumes of sediment since then, most of these ancient rocks have been on a gently sloping plain. Sandstone was deposited buried and recrystallized, obscuring their original in river channels and dunes, and mud was deposited textures and composition. The Precambrian rocks in across the landscape during flood events. southern Sweet Grass County were deposited under The Laramide Orogeny continued throughout late- water in a large basin and subsequently folded and Cretaceous time into the early Tertiary, accompanied metamorphosed under high pressures and by intermittent, explosive volcanism. Deep-seated temperatures. Metal-rich dikes were emplaced along melting created masses of magma that rose into the fractures during a period of volcanic activity that upper crust. As it rose, it deformed the surrounding occurred about 2.7 billion years ago. sedimentary formations, lubricated planes of thrust A long, quiet period followed, and the Precambrian faulting, and, in many areas, mineralized the Age drew to a close approximately 570 million years surrounding rock. Some of the magma rose to the ago. The subsequent Paleozoic Era is marked by the surface, forming extrusive as well as intrusive first appearance of fossils of multicellular animals igneous rocks. Cretaceous-aged volcanic rocks with hard parts. By middle Cambrian time, the occur in the southern part of the soil survey area. Archean-aged rocks had been uplifted and eroded Age dating of the Independence Stock shows that Sweet Grass County Area, Montana—Part I 5

volcanic activity was initiated 92 million years ago, large igneous bodies with numerous sills, smaller with its main intrusive phase occurring 84 million intrusions, and dike swarms associated with them. years ago. Their composition is generally alkaline, and there The Laramide Orogeny produced the most are no extrusive rocks. The surrounding sedimentary extensive volcanism that has occurred in western rocks were upturned and baked during these Montana, and it spread thick layers of volcanic ash intrusive events. over this area. Bentonite, which is derived from The climate turned mild and dry 40 million years weathered volcanic ash, occurs in many of the ago, and large quantities of sediment were deposited Cretaceous-aged sediments, particularly the marine across the Great Plains. Approximately 25 million shales. It is found in layers from a few inches to a few years ago, the weather turned hot and wet and feet thick. remained that way for 10 million years. Rolling The Cretaceous Period ended approximately landscapes developed as rivers began eroding 65 million years ago with a decline in the intense valleys into a lush, tropical landscape. Then, mountain-building activity and the extinction of the 15 million years ago, the climate changed again, dinosaurs. While the fossils changed significantly, the becoming extremely dry and probably colder. There deposition of massive amounts of sediment from the was little plant cover, and flash floods spread uplifting Rocky Mountains continued into the blankets of gravel across the landscape, forming Cenozoic Era. the high plains. Gravel choked the streams and no At the beginning of the Tertiary Period, there was permanent channels could be established. still a shallow sea to the east and the climate was At the beginning of the Quaternary Period, the warm and wet. Swamps, containing abundant climate became wetter again. Plant cover was subtropical vegetation, developed along the rivers reestablished, minimizing erosion. Rivers and and the coastal plain. As the sluggish rivers shifted streams, including the Yellowstone River, became and meandered, this vegetation was buried by the entrenched, beginning to form the channels we see accumulating sediment and eventually converted to today. Since then cold, wet intervals of ice advances coal. have alternated with drier interglacial periods. Fifty million years ago, after a relatively quiet Geologists estimate that there may have been up to period in the early Tertiary, a major uplift occurred, 20 separate ice advances affecting Montana in the caused by compressional forces from the west. Large last 3 million years (Alt, 1984). During these ice fault systems and broad folds developed, and the advances, alpine glaciers covered the high peaks, Beartooth Block was uplifted. Geologists have eroding jagged ridgetops and U-shaped valleys and estimated that the northeastern side of the Beartooth depositing linear moraines and glacial outwash in Block has been uplifted from 15,000 to 20,000 feet many valleys. (4,570 to 6,100 m) (Simons and others, 1979). Today, Sweet Grass County is moderately quiet. At the same time, an enormous quantity of Mountain building is active to the west, although in andesitic lava and other volcanic deposits were Sweet Grass County it is less intense. Minor faulting extruded in the South Snowy Block of the Beartooth is still possible. There are active glaciers in the high Mountains. This volcanic sequence is known as the peaks of both the Crazy and Beartooth Mountains. Absaroka Volcanic Field. It covers approximately Presently, the streams are in a cycle of downcutting, 9,000 square miles (23,310 km2) and extends from depositing alluvium along stream channels and the Gallatin Range of southwestern Montana into across flood plains during periods of flooding. northwestern Wyoming. This volcanic belt lies along a Geologic Structure Precambrian-age, northwest-trending zone of crustal weakness named the Cooke City Fault Zone, which The principal geologic structures in Sweet Grass determines its northeastern boundary. This regional County are the Beartooth Uplift and the Crazy zone of weakness apparently controlled the location Mountains Basin. Immediately northeast of the of both volcanic and intrusive centers and the Beartooth Mountains, Paleozoic sedimentary rocks distribution of mineralized areas. Radioactive dates are upturned and faulted in complex patterns. North on these rocks range from 49 to 55 million years ago, of this faulted zone, the sedimentary rocks dip into or early to mid-Eocene. the Crazy Mountains Basin, becoming progressively The intrusive rocks that form the core of the younger at the surface toward the center of the basin. Crazy Mountains were also emplaced at this time. Minor folding, which appears at the surface of the The Crazy Mountains are composed of several Crazy Mountains Basin, covers more extensive 6 Soil Survey

subsurface folding in older rocks. The rocks in the overlying Mission Canyon Formation, and has a total southeastern corner of the soil survey area dip thickness of 1,100 feet (335 m). Typical soils southeast into the Reed Point syncline. weathered from limestone include the Lap and Several major faults transect the Beartooth Whitore series. Mountains in the southern portion of the county, The remaining Paleozoic section in Sweet Grass including the Mill Creek-Stillwater Fault Zone, the County consists of approximately 1,000 feet (305 m) Nye-Bowler Lineament, and the western tip of the of soft sedimentary rocks that are individually thin Beartooth Fault. The Cooke City Fault Zone is a major and indistinct in outcrop. The older formations were structural zone that cuts through the interior of the deposited on the irregular topography caused by Beartooth Uplift. This fault zone extends northwest limestone dissolution in the Mission Canyon from the Sunlight Basin in Wyoming through southern Formation when it was exposed at the surface. This Sweet Grass County to the Mill Creek area south of dissolution caused erratic distribution and varying Livingston. thicknesses of the sedimentary units. Geologic Units Mesozoic “Middle Life” System 245 to 66 mya The sequence of sedimentary rocks exposed in the Sweet Grass County soil survey area is Triassic Period (245 to 208 mya) summarized below, in order of decreasing age. Formations are defined as a succession of strata Rocks deposited during the Triassic Period were distinctive enough to constitute a basic unit for soil removed by erosion during the Jurassic Period; there survey, identified by similar rock type and are no Triassic rocks preserved in this area. stratigraphic section. Formations can be combined Jurassic Period (208 to 144 mya) into groups or subdivided into members. Systems are the rocks deposited during a particular geologic Jurassic-aged sedimentary rocks are thin and period. poorly exposed and crop out only in a thin band near The Geologic Map of Montana (Ross, 1955), was the southern margin of the soil survey area. used for the compilation of this report where newer Consequently, they are not associated with any geological data was unavailable. Descriptions and particular soil series. Sediments in the uppermost nomenclature of some of the rock units on this map Morrison Formation represent the change from have changed considerably since its publication; marine to nonmarine deposition in southern however, there has been little additional mapping Montana. published, particularly in the northern part of the Cretaceous Period (144 to 66 mya) county. Geologic mapping is ongoing in this area, so the designated outcrop areas may be changed; The oldest Cretaceous rocks belong to the however, rock types associated with individual Kootenai Formation. It is nonmarine and has been formations should remain consistent. subdivided into two members. The lower member, the Representative soil series are listed for each Pryor Conglomerate, is a massive, crossbedded unit formation, where possible. In some cases, outcrop between 25- and 40-feet (8- and 12-m) thick and is areas for a particular formation are small and difficult commonly ridge-forming. It consists primarily of chert- to differentiate in the field. In these cases, no soil gravel conglomerate and sandstone. The upper series are correlated with the formation. member of the Kootenai Formation is a poorly exposed sequence of red, purple, green, and gray Paleozoic “Ancient Life” System mudstone and shale with interbeds of sandstone, 570 to 245 million years ago (mya) siltstone, and limestone. This upper member is The oldest rocks in the soil survey area are between 220- and 260-feet (67- and 79-m) thick. Paleozoic rocks, which are exposed in the far Typical soils weathered from this formation include southwestern corner of the soil survey area, on the the Bridger and Danaher series. northern flank of the Beartooth Mountains. Paleozoic The overlying Thermopolis Shale is a marine rocks are carbonate rocks belonging to the Madison formation, consisting of a thin lower sandstone Group, consisting primarily of limestone, and can be member, a middle shale member, and a thin upper seen forming the high cliffs near Natural Bridge. The sandstone member. This formation is approximately Madison Group has been subdivided into two 500-feet (152-m) thick and consists primarily of the formations, the Lodgepole Limestone and the dark-gray shales of the middle member. The shales Sweet Grass County Area, Montana—Part I 7

weather to light gray and are distinguished from the coal, carbonaceous mudstones, and tuff. Its basal overlying Mowry Shale by color. Mowry shales are member, the Virgelle Sandstone, is a persistent, light- brownish gray and weather to yellowish gray. gray sandstone that is hard and massive. The Eagle The Mowry Shale is between 430- and 500-feet Formation has an average thickness of 600 feet (131- and 152-m) thick and is composed of dark-gray (183 m) and was deposited in brackish water at the to dark-brown marine shale with minor interbeds of edge of a regressing sea in lagoons, deltas, swamps, sandstone, siltstone, and bentonite. This shale was and beaches. It is exposed in a large area south of deposited in deep, quiet water and contains abundant McLeod and, in this area, contains mineable coal fish scales. The Mowry and Thermopolis Shales are deposits. Typical soils weathered from this formation both easily erodible. They occur together in include the Cheadle and Lymanson series. depressions between ridges formed by the more For the sedimentary rocks above the Eagle resistant sandstones in the underlying Kootenai and Formation, the state geologic map shows both the overlying Frontier Formations. Landslides are continental and marine deposits of the same age in prevalent in these shales and can be seen along the Sweet Grass County. The continental deposits lie to valley sides south of McLeod. There is a large slide the west and have been assigned to the Livingston affecting the Boulder River Road at the short Group. Marine deposits that lie to the east have been graveled section at mile marker 22. Typical soils assigned to the Montana Group. The Livingston formed on these shale formations include the Linwell Group consists of the Cokedale, Miner Creek, and Wayden series. Billman Creek, and Hoppers Formations; these The overlying Frontier Formation consists of a sedimentary rocks are composed primarily of sequence of thin-bedded, crossbedded greenish- and volcanic fragments. Mapping of individual formations yellowish-gray calcareous sandstone with interbeds within the Livingston Group has not been extended of siltstone, gravel conglomerate, and coal. It has a into Sweet Grass County from the west, so they will uniform thickness of 415 feet (126 m) in the not be differentiated here. The Montana Group is Livingston-McLeod area; however, the upper part is composed of the Claggett Shale, Judith River not generally well exposed. The basal member is a Formation, Bearpaw Shale, and Lennep Sandstone. 100-foot (30-m) thick sandstone unit which is The Livingston Group contains a thick unit of exposed on the west side of the Boulder River valley volcanic rocks formed from a series of volcanic near McLeod, called the Boulder River Sandstone. mudflows, or lahars, with volcanic breccias. It consists Typical soils weathered from this formation include of angular fragments of dark-gray andesite the Castner and Reedwest series. suspended in mud and volcanic ash. This The overlying Cody Shale is a nonresistant assemblage of volcanic rubble is known as “Weed’s sequence composed primarily of shale that forms Agglomerate” or the “Livingston Igneous Series,” and grassy slopes and valleys. It consists of dark it occurs in a large block to the south and southeast brownish-gray marine shale with thin interbeds of of Big Timber, extending just to the north of, and bentonite and sandstone, and it has a middle beyond, Nye. It is well exposed in the high cliffs sandstone member named the Eldridge Creek approximately 8 miles (13 km) south of Big Timber on Member that ranges in thickness from 90 to 120 feet the Boulder River Road. Its stratigraphic position (27 to 37 m). The formation has a total thickness within the Livingston Group is still uncertain and it ranging from 1,285 to 1,375 feet (392 to 419 m). has not been assigned to a particular formation. Typical soils weathered from this formation include Typical soils weathered from this formation include the Absarokee and Amherst series. the Pianohill and Weedzunit series. The Telegraph Creek Formation is a shallow-water The marine sedimentary section assigned to the marine siltstone that is transitional between the Montana Group consists of from 1,850 to 2,150 feet underlying Cody Shale and the overlying Virgelle (564 to 655 m) of interbedded sandstone, siltstone, Sandstone Member of the Eagle Formation. It is and shale. They are exposed in a thin band northwest approximately 300-feet (91-m) thick and contains and southeast of McLeod and are covered by interbeds of sandstone, mudstone, and shale. The Cretaceous volcanics to the northeast. They are also sandstone interbeds increase up section, eventually exposed in the South Fork of Big Coulee Creek, in grading into the Virgelle Sandstone. the northeastern corner of the county. The Eagle Formation consists of well-bedded to The Claggett Shale consists of soft, light-gray massive, crossbedded sandstone with interbeds of marine shales with thin, light-gray or white sandstone 8 Soil Survey

interbeds. It is over 400-feet (122-m) thick. Typical interbedded with siltstone and mudstone. These soils weathered from this formation include the sediments were deposited on an extensive flood Wayden and Work series. plain, and the individual beds tend to be lenticular, The Judith River Formation consists of light- with limited areal extent. Many are poorly cemented. colored, interbedded sandstone and sandy shales The Fort Union Formation covers approximately that are locally carbonaceous. It has a basal the northeastern quarter of the soil survey area; it sandstone, the Parkman Sandstone, that is a soft, extends from Big Timber north and east to near the massive, buff sandstone with hard, dark concretions; eastern border of the county. Further geologic the sandstone is up to 300-feet (91-m) thick. The full mapping will probably extend this formation to the thickness of the formation is approximately 600 feet west toward the Crazy Mountains. In other areas of (183 m). Montana, the Fort Union Formation has been The Bearpaw Shale is composed of from 600 to subdivided on the basis of color, rock type, and the 700 feet (185 to 215 m) of gray to black, bentonitic occurrence of coal; however, further geologic shales containing calcareous concretions. It forms the mapping is required to delineate these subdivisions broad valley in the upper portion of the South Fork of in Sweet Grass County. Big Coulee Creek. Typical soils weathered from this The Tertiary-aged igneous complex that forms formation include the Kobase and Tanna series. the core of the Crazy Mountains contains a varied The Lennep Sandstone, which in this area may be assemblage of intrusive rocks. The southern end of equivalent to the lower Hell Creek Formation, is the the Crazy Mountains is formed by the Big Timber youngest unit to be designated in the Montana Group. Stock, which consists primarily of diorite, a medium- It is a marine deposit that consists of dark-colored, colored, coarse-grained rock that is low in silica. In tuffaceous sandstone with thin interbeds of dark Sweet Grass County south of the high peaks, there shale. It is ridge-forming and varies in thickness from are a number of smaller intrusions and large, vertical 250 to 460 feet (76 to 140 m), overlying the softer, dike swarms associated with the main stock that have erosive shales of the Bearpaw Formation. Typical intruded and metamorphosed the surrounding soils weathered from this formation include the sediments. Their composition is higher in sodium and Hinterland and Reedpoint series. potassium than the main intrusion. The intruded The Hell Creek Formation overlies the Lennep sediments have been baked and hardened to a Sandstone and is the youngest sedimentary hornfels, which is as hard and resistant to erosion as formation of the Cretaceous Period. It outcrops in the the surrounding igneous rocks. Typical soils formed eastern half of the county in a broad, northwest- from these hard, volcanic rocks are the Perma and trending band straddling the Yellowstone River for Whitlash series. several miles on either side. It is from 500- to 750-feet The Absaroka Volcanic Field covers the South (152- to 230-m) thick and is composed primarily of Snowy Block of the Beartooth Range and is exposed soft, fine- to medium-grained, gray to brown lenticular in the southern part of Sweet Grass County. The beds of sandstone, interbedded with green to gray Absaroka Volcanic Field is composed of large claystone and sandy shale. Sandstone beds are often volumes of andesitic lava flows, volcanic breccias, over 25-feet (8-m) thick. Thin, discontinuous coal and tuffs, with small, localized intrusive necks, dikes, seams, carbonaceous shales, and bentonite are also and sills. The andesite flows consist of platy, dark- common within the formation. Unsurfaced roads in gray, porphyritic rocks. Porphyritic rocks contain large the Hell Creek Formation tend to be quite slick when crystals in a fine-grained groundmass. The breccias wet. Typical soils formed on the sandstone bedrock contain coarse, angular volcanic blocks in a rusty include the Delpoint and Rentsac series. Typical soils weathering matrix. Typical soils weathered from these formed on the shale bedrock include the Megonot volcanic rocks include the Arrowpeak and Timberlin and Yawdim series. series. Cenozoic “Recent Life” System Quaternary Period (1.6 mya to present) 66 mya to present There are a variety of surficial Quaternary deposits Tertiary Period (66 to 1.6 mya) located within the soil survey area. They consist primarily of alluvium, terrace deposits, and glacial The Fort Union Formation contains the oldest moraines and outwash. They are generally rocks from the Tertiary Period. This formation is unconsolidated and relatively thin. Only the major nonmarine and consists of approximately 6,600 feet drainages contain significant amounts of Quaternary- (2,012 m) of sandstone and conglomerate aged alluvium. Sweet Grass County Area, Montana—Part I 9

There are unconsolidated terrace deposits on Stillwater County and gold and silver mining in the some valley sides and upland areas of the Beartooth Mountains and on the eastern side of the Yellowstone River valley. They are remnants of former Crazy Mountains. flood plains of both the Yellowstone and Boulder The Stillwater Complex crops out in Park, Sweet Rivers and consist primarily of partially cemented, Grass, and Stillwater Counties in an area 28-miles rounded gravel and cobbles. Two separate terrace (45-km) long by 5-miles (8-km) wide along the levels of the Yellowstone River can be seen in the northern edge of the Beartooth Mountains. This area Big Timber area. The Yellowstone River terraces contains a diverse assortment of mineral deposits include the low terrace underlying the towns of associated with an unusual, layered ultramafic Springdale and Big Timber and the terrace at Airport intrusion (rocks high in iron and magnesium thought Flats, 500 feet (152 m) above the Yellowstone River. to be weathered from the mantle) that was emplaced McKenzie Flats is considered to be a terrace deposit 2.7 billion years ago during the Archean Eon. of the Boulder River. Historically, mining districts in this area produced Age dating of these surfaces was performed using gold, silver, arsenic, tungsten, copper, lead, zinc, and weathering rinds on cobbles within the gravel chromium; most of which was transported out of the deposits and on accumulations of caliche. This data area. The Stillwater Complex deposit contains all of shows the Big Timber surface to have formed the identified platinum-group element (PGE) approximately 140,000 years ago and the higher resources in the United States; 75 percent of the terrace at Airport Flats to have formed 1.5 million identified chromium resources of the United States; years ago (Rayne, 1995). Two intermediate terrace and significant gold, silver, copper, lead, and zinc levels of the Yellowstone River have been mapped resources. PGEs include platinum and palladium, between Springdale and Livingston; however, they with lesser amounts of rhodium, ruthenium, osmium, are missing in Sweet Grass County. Soils formed in and iridium. They are used as catalysts in petroleum older terrace deposits are the Sweetgrass and refining and the chemical industry and in catalytic Tamaneen series. Soils formed in younger terrace converters for automobiles. Because these metals deposits include the Roy and Turner series. are inert, they are also used in medical and dental There are glacial deposits in both the Crazy and applications. Beartooth Mountains. They are primarily moraine, The Independence Mining District, in southwestern which is a hummocky, unsorted deposit that covers Sweet Grass County, is one in a series of mining valley bottoms and extends up adjacent slopes. There districts located in the Absaroka Volcanic Field along is a good example of a moraine in the vicinity of the the northwest-trending Cooke City Fault Zone. This old school near Elk Creek on the East Boulder River fault zone may have been a major eruptive center and in the Crazy Mountains northwest of Melville during the Eocene Epoch. Within this zone, between Sweet Grass Creek and American Fork. mineralization and alteration were caused by Soils formed in glacial moraines include the Shawmut hydrothermal solutions upwelling along existing and Stemple series. fracture systems during Late Cretaceous and Eocene Alluvial deposits formed in the last 10,000 years time. can be found along the Yellowstone River and its In 1864, gold was discovered in the Independence tributaries, although the most extensive are in the Mining District, near the head of the Boulder River flood plains of the Yellowstone River and lower between Monument Peak and Baboon Mountain. The portions of the Boulder River. These deposits are district included three mines that operated between unconsolidated and consist of sand and gravel with 1900 and 1940 and produced minor amounts of gold, local lenses of silt and clay. Typical soils weathered silver, and copper. The last mine was closed in 1942. from these deposits include the Meadowcreek and Small amounts of gold, silver, and copper were Nesda series. intermittently mined from the Natural Bridge District on the Boulder River between 1901 and 1937. Mining Mining claims were first located here in 1882 when the area was excluded from the Crow Indian Reservation. Mining activity in Sweet Grass County has Gold occurs in quartz-filled fissures in Precambrian primarily occurred in the mountains outside of the soil metamorphic rocks. Exploration for Stillwater survey area; however, mining has had a significant Complex mineralization is ongoing in this area as impact on the development of the county. Mining well. activity has consisted primarily of exploration The Deer Creek Mining District lies approximately associated with the Stillwater Complex deposits in 16 miles (26 km) south of Big Timber, on Upper Deer 10 Soil Survey

Creek, approximately 3 miles (5 km) south of the soil older rocks. There are members of the oil and gas survey area boundary. Prospecting for gold, silver, industry who remain optimistic about this area; and copper has occurred in this district since the however there is little ongoing exploration at this time. 1900s; however, the majority of the mining was in the There is a significant amount of federal land south 1920s. Exploration for copper is ongoing in this area. and northwest of Big Timber that has been leased to In the 1940s, optical-quality calcite was mined private industry for energy exploration. from the upper Deer Creek drainage, 3 miles (5 km) Small amounts of coal were mined from the Eagle north of Iron Mountain, for use in bomb sights Formation, west of the Boulder River Road at Coal manufactured by Norden for bomber aircraft. It was Mine Rim, 3 miles (5 km) south of McLeod. There is also mined locally for chicken grits. Most of the little published information about this mining; however material was mined from veins cutting sedimentary it is assumed that this mining took place in the late rocks of the Livingston Group, but these veins also 1800s and early 1900s, at the same time as the occur in the Livingston agglomerate unit. The calcite active coal mining in Cokedale, 25 miles (40 km) to was deposited into open fractures by rising, low- the west. temperature hydrothermal solutions associated with volcanic activity. The veins occupy faults and can be Geothermal Resources up to 20-feet (6-m) thick and traceable for several thousand feet. The McLeod Basin in the southern end of the soil The Big Timber District is several miles west of survey area is approximately 45 miles (72 km) Half Moon Campground and encompasses the northeast of Gardiner, Montana, and the entrance headwaters of Big Timber Creek in the Crazy to Yellowstone National Park. The park contains Mountains. It is a relatively small district and contains the largest geothermal system in North America, gold, silver, lead, and copper. Exploration has the Yellowstone caldera. There are no Known continued in this district sporadically from the 1920s Geothermal Resource Areas (KGRAs) designated to the present. by the United States Department of the Interior in Sweet Grass County, although there are several Oil, Gas, and Coal thermal springs and wells. These springs and wells include Hunter’s Hot There are no producing oil- or gasfields in Sweet Springs, Anderson’s Spring near McLeod, and the Grass County at this time. There has been some McLeod well. Hunter’s Hot Springs is an old resort exploration over the years in the Crazy Mountains area that was closed in the late 1960s. It is currently Basin, and a total of 79 exploration holes were drilled used to heat greenhouses. It has a reported flow in the county between 1923 and 1992 (Montana of 1,135 gpm (4,290 L/min) and a temperature of Board of Oil and Gas Conservation, 1995). Forty- 138 degrees F (59 degrees C). Anderson’s Spring eight of these holes were dry; the rest had at McLeod is currently undeveloped. It has a reported noncommercial shows of oil and gas. The deepest flow of 75 gpm (280 L/min) and a temperature of hole was drilled near Porcupine Butte in Section 6, 77 degrees F (25 degrees C). The geothermal well T. 5 N., R. 13 E., to a total depth of 11,800 feet at McLeod has a total depth of 2,250 feet (686 m). It (3,597 m). is reported to flow at 1,135 gpm (4,290 L/min), with The Crazy Mountains Basin is composed of a very a temperature of 104 degrees F (40 degrees C). thick accumulation of sedimentary rocks, estimated to be nearly 30,000-feet (9,145-m) thick in the center of Ground-Water Resources the basin. These sediments contain a significant amount of relatively porous sandstone. The basin is The most productive water wells in Sweet Grass considered to have moderate potential for oil and gas County are developed from alluvial gravels along the development as there are mature petroleum source Yellowstone and Boulder River flood plains. North of strata present at depth; there is permeable rock the Yellowstone River, quantities of water suitable for above the source strata that would allow petroleum stock and domestic use can be developed from migration; and structures are present that are sandstone beds within the Fort Union Formation, the normally associated with petroleum traps. Livingston Group, and the Hell Creek and Lennep Unfortunately, the basin is structurally complex, Formations. In the relatively flat-lying beds in the and gentle folding of the Tertiary rocks at the surface Crazy Mountains Basin, well depth is partially obscures more complicated folding in the underlying, dependent on the topography and, particularly, on the Sweet Grass County Area, Montana—Part I 11

proximity of the well to the nearest stream. In general, a total of 11 earthquakes recorded in Sweet Grass drilling on ridgetops or divides results in the deepest County since the network began in 1982. Their wells with the greatest pump lifts in the area. Richter magnitudes range between 1.5 and 3.0. South of the Yellowstone River, water can be Earthquakes with magnitudes of 2.0 or less are developed from formations composed primarily of known as microearthquakes. They are not commonly sandstone. Shale formations are saline and felt and are recorded only on local seismographs. It impermeable and are not reliable aquifers. In a is unusual for earthquakes with magnitudes under limited area at the south end of the soil survey area, 4.5 to cause any significant damage. While this the Madison Limestone is capable of significant historical record is very short, there is evidence to yields. indicate a moderate to low risk of seismicity in Sweet Well use, current to May, 1995, for Sweet Grass Grass County. County is summarized below. This information is contained within the database maintained by the Climate Montana Groundwater Information Center at the Bureau of Mines and Geology in Butte. A total of Natural Resources Conservation Service, National Water and 965 well records are recorded. Many wells have Climate Center, Portland, Oregon, prepared this section. multiple uses, most commonly domestic and stock Climate tables were created from climate stations water, so the sum of the uses appears to be greater Big Timber, located in the southern portion of this soil than the total number of wells. survey area, and Melville 4W, located in the northern WATER USE ...... NUMBER OF WELLS portion. Domestic ...... 594 Thunderstorm days, relative humidity, percent Stock water ...... 462 sunshine, and wind information were estimated from Irrigation ...... 81 First Order station Billings. Unused ...... 22 The “Temperature and Precipitation” table gives Public water supply ...... 6 data on temperature and precipitation in the survey Industrial ...... 3 area, as recorded at Big Timber and Melville in the Monitoring ...... 3 period 1971 to 2000. The “Freeze Dates in Spring Commercial ...... 2 and Fall” table shows probable dates of the last freeze in spring and the first freeze in fall. The No wells had reported yields of greater than “Growing Season” table provides data on length of 1,000 gpm (3,780 L/min); 8 wells had reported yields the growing season. of greater than 100 gpm (378 L/min); and 273 wells In the Sweet Grass County soil survey area, reported yields greater than 20 gpm (76 L/min). summers are generally warm with frequent hot days Ten wells had total depths greater than 1,000 feet on the plains. In the foothill and mountain areas, (305 m); 42 had total depths greater than 250 feet summer temperatures are cooler. Throughout the soil (76 m); and 216 had total depths greater than survey area, most precipitation falls as rain during the 100 feet (30 m). A total of 402 wells had yields warmest part of the year. Rain is normally heaviest in between 1 and 10 gpm (4 to 38 L/min). late spring and early summer. In some years, summer hailstorms cause local damage to crops. Seismicity In summer, the average temperatures are 66.7 and 59.3 degrees F, respectively, at Big Timber and Sweet Grass County lies a few miles east of the Melville. The average daily maximum temperatures Intermountain Seismic Belt, which contains most of in summer are 83.2 and 73.2 degrees F, respectively. the known active faults in Montana, Idaho, Wyoming, The highest temperatures on record were and Utah. Most seismicity maps published by the 110 degrees F at Big Timber on July 21, 1931, United States Geological Survey or other sources list and 93 degrees F at Melville on July 28, 1999. Sweet Grass County in the moderate to minor During winter on the plains, brief periods of very earthquake risk categories. Seismic potential of the cold weather occur when arctic air moves in from the area decreases to the northeast, away from the north or northeast. Cold periods alternate with milder Hebgen Lake-Yellowstone National Park area. periods that occur often when strong westerly winds The Earthquake Studies Office of the Montana are warmed as they move downslope. In the foothill Bureau of Mines and Geology maintains a network and mountain areas, winters are colder, with less of seismographs throughout Montana. Information periods of milder weather. On the plains, winter provided by the Earthquake Studies Office shows snowfalls are frequent, but snow cover generally 12 Soil Survey

disappears during mild periods. In the foothill and The average relative humidity in midafternoon is mountain areas, snow cover is more persistent, and a about 30 percent in the summer and about deep snowpack accumulates at the higher elevations. 55 percent in the winter. Humidity is higher at night, Snow melt generally provides adequate water for and the average at dawn is between 65 and agricultural purposes. In some years, winter blizzards 70 percent in all months. The sun shines about with heavy snows, strong winds, and drifting snow 72 percent of the time in summer and about strike the area. 48 percent in winter. The prevailing wind is from the In winter, the average temperatures are 28.4 and west or southwest. The average wind speed is 24.0 degrees F, respectively, at Big Timber and highest, about 13 miles per hour, in December and Melville. The average daily minimum temperatures January. are 17.9 and 12.3 degrees F, respectively. The lowest temperatures on record were –47 degrees F at Big How This Survey Was Made Timber on February 15, 1936, and –45 degrees F at Melville on February 3, 1989. This survey was made to provide information Growing-degree days, as shown in the about the soils and miscellaneous areas in the “Temperature and Precipitation” table, are equivalent survey area. The information includes a description of to heat units. During the month, growing-degree days the soils and miscellaneous areas and their location accumulate by the amount that the average and a discussion of their suitability, limitations, and temperature each day exceeds a base temperature management for specified uses. Soil scientists (40 degrees F). The normal monthly accumulation observed the steepness, length, and shape of the can be used to schedule single or successive slopes; the general pattern of drainage; the kinds of plantings of a crop between the last freeze in spring crops and native plants; and the kinds of bedrock. and the first freeze in fall. They dug many holes to study the soil profile, which The average annual total precipitation over the is the sequence of natural layers, or horizons, in a survey area is generally between 15 and 18 inches. soil. The profile extends from the surface down into Over the higher elevation areas near the mountains the unconsolidated material in which the soil formed. in the northwest and the extreme south of the survey The unconsolidated material is devoid of roots and area, annual precipitation goes above 20 inches. other living organisms and has not been changed by At Big Timber, the average annual precipitation is other biological activity. 16.29 inches, and, at Melville, it is 17.60 inches. The soils and miscellaneous areas in the survey Of these amounts, about 10 inches, or around area are in an orderly pattern that is related to the 60 percent of the average annual, generally falls in geology, landforms, relief, climate, and natural May through September. The growing season for vegetation of the area. Each kind of soil and most crops falls within this period. The heaviest miscellaneous area is associated with a particular 1-day rainfalls during the periods of record were kind of landform or with a segment of the landform. 4.00 inches at Big Timber on May 19, 1938, and By observing the soils and miscellaneous areas in 2.93 inches at Melville on August 1, 1976. the survey area and relating their position to specific Thunderstorms occur on about 28 days each year, segments of the landform, a soil scientist develops a and most occur between late May and mid-August. concept or model of how they were formed. Thus, The average seasonal snowfall is somewhat during mapping, this model enables the soil scientist dependent on elevation. At Big Timber, the average to predict with a considerable degree of accuracy the annual snowfall is 30.7 inches, while at Melville, kind of soil or miscellaneous area at a specific nearly 1,300 feet higher, it is 44.7 inches. The location on the landscape. greatest snow depths at any one time during the Commonly, individual soils on the landscape periods of record were 24 inches at Big Timber merge into one another as their characteristics on December 26, 1996, and 22 inches at Melville gradually change. To construct an accurate soil map, on January 26, 1975. On average, about 20 days however, soil scientists must determine the per year have at least 1 inch of snow on the ground boundaries between the soils. They can observe only at Big Timber and about 30 to 40 days are common a limited number of soil profiles. Nevertheless, these at higher elevations. The heaviest 1-day snowfalls observations, supplemented by an understanding of on record were 24.0 inches recorded on January 26, the soil-vegetation-landscape relationship, are 1975, at Big Timber and 18.0 inches at Melville on sufficient to verify predictions of the kinds of soil in an April 4, 1997. area and to determine the boundaries. Sweet Grass County Area, Montana—Part I 13

Soil scientists recorded the characteristics of the Interpretations for all of the soils are field tested soil profiles that they studied. They noted soil color, through observation of the soils in different uses and texture, size and shape of soil aggregates, kind and under different levels of management. Some amount of rock fragments, distribution of plant roots, interpretations are modified to fit local conditions, and reaction, and other features that enable them to some new interpretations are developed to meet local identify soils. After describing the soils in the survey needs. Data are assembled from other sources, such area and determining their properties, the soil as research information, production records, and field scientists assigned the soils to taxonomic classes experience of specialists. For example, data on crop (units). Taxonomic classes are concepts. Each yields under defined levels of management are taxonomic class has a set of soil characteristics with assembled from farm records and from field or plot precisely defined limits. The classes are used as a experiments on the same kinds of soil. basis for comparison to classify soils systematically. Predictions about soil behavior are based not only Soil taxonomy, the system of taxonomic classification on soil properties but also on such variables as used in the United States, is based mainly on the climate and biological activity. Soil conditions are kind and character of soil properties and the predictable over long periods of time, but they are not arrangement of horizons within the profile. After the predictable from year to year. For example, soil soil scientists classified and named the soils in the scientists can predict with a fairly high degree of survey area, they compared the individual soils with accuracy that a given soil will have a high water table similar soils in the same taxonomic class in other within certain depths in most years, but they cannot areas so that they could confirm data and assemble predict that a high water table will always be at a additional data based on experience and research. specific level in the soil on a specific date. While a soil survey is in progress, samples of After soil scientists located and identified the some of the soils in the area generally are collected significant natural bodies of soil in the survey area, for laboratory analyses and for engineering tests. Soil they drew the boundaries of these bodies on aerial scientists interpret the data from these analyses and photographs and identified each as a specific map tests as well as the field-observed characteristics and unit. Aerial photographs show trees, buildings, fields, the soil properties to determine the expected roads, and rivers, all of which help in locating behavior of the soils under different uses. boundaries accurately. 14 Soil Survey

Temperature and Precipitation

(Recorded in the period 1971 through 2000 at Big Timber and Melville)

______| | | Temperature (Degrees F) | Precipitation (Inches) ______| | | | | | | | | | | | | | | 2 Years in 10 | Average | | 2 years in 10 | Average | |Average|Average| | Will Have— | Number | | Will Have— | Number | Average Month | Daily | Daily | Average | | | of | Average | | | of Days | Total |Maximum|Minimum| | Maximum | Minimum | Growing-| | Less | More | With | Snowfall | | | |Temperature|Temperature| degree | | Than | Than | 0.10 or | | | | | More Than | Less Than | Days* | | | | More | ______| | | | | | | | | | | | | | | | | | | | | | BIG TIMBER: | | | | | | | | | | | | | | | | | | | | | | January-----| 36.8 | 16.0 | 26.4 | 60 | -23 | 22 | 0.69 | 0.27 | 1.10 | 2 | 5.5 February----| 42.1 | 19.4 | 30.8 | 64 | -19 | 37 | 0.50 | 0.11 | 0.88 | 1 | 4.3 March------| 49.6 | 24.6 | 37.1 | 72 | -11 | 84 | 0.93 | 0.46 | 1.32 | 3 | 4.6 April------| 59.0 | 31.6 | 45.3 | 82 | 11 | 200 | 1.83 | 0.64 | 2.99 | 5 | 2.1 May------| 68.2 | 39.5 | 53.9 | 89 | 25 | 431 | 2.87 | 1.63 | 3.88 | 6 | 0.2 June------| 78.0 | 47.4 | 62.7 | 97 | 33 | 668 | 2.60 | 1.14 | 3.81 | 5 | 0.0 July------| 86.2 | 52.2 | 69.2 | 101 | 40 | 891 | 1.54 | 0.55 | 2.39 | 3 | 0.0 August------| 85.5 | 50.9 | 68.2 | 99 | 37 | 855 | 1.25 | 0.38 | 2.14 | 3 | 0.1 September---| 74.0 | 41.4 | 57.7 | 94 | 24 | 531 | 1.28 | 0.53 | 1.98 | 3 | 0.5 October-----| 61.3 | 33.5 | 47.4 | 83 | 8 | 269 | 1.37 | 0.53 | 2.19 | 3 | 1.7 November----| 45.2 | 24.6 | 34.9 | 69 | -8 | 69 | 0.73 | 0.31 | 1.09 | 2 | 4.6 December----| 38.0 | 18.2 | 28.1 | 60 | -23 | 22 | 0.71 | 0.20 | 1.17 | 2 | 7.2 | | | | | | | | | | | Yearly: | | | | | | | | | | | Average---| 60.3 | 33.3 | 46.8 | ——— | ——— | ——— | ——— | ——— | ——— | ——— | ——— Extreme---| 104.0 | -38.0 | ——— | 101 | -28 | ——— | ——— | ——— | ——— | ——— | ——— Total-----| ——— | ——— | ——— | ——— | ——— | 4,080 | 16.29 |12.72 | 19.16 | 38 | 30.7 | | | | | | | | | | | | | | | | | | | | | | MELVILLE: | | | | | | | | | | | | | | | | | | | | | | January-----| 34.0 | 10.9 | 22.5 | 58 | -26 | 7 | 0.62 | 0.21 | 0.96 | 2 | 4.0 February----| 37.6 | 13.9 | 25.8 | 60 | -26 | 9 | 0.50 | 0.17 | 0.80 | 2 | 5.5 March------| 42.7 | 19.2 | 31.0 | 65 | -16 | 24 | 1.18 | 0.61 | 1.69 | 3 | 11.5 April------| 51.1 | 26.4 | 38.7 | 74 | 2 | 89 | 1.91 | 0.87 | 2.90 | 5 | 9.9 May------| 60.0 | 34.8 | 47.4 | 80 | 19 | 248 | 2.84 | 1.47 | 4.14 | 6 | 0.7 June------| 68.4 | 42.3 | 55.4 | 85 | 29 | 461 | 2.95 | 1.36 | 4.27 | 7 | 0.0 July------| 75.6 | 47.2 | 61.4 | 90 | 34 | 664 | 2.14 | 0.82 | 3.27 | 5 | 0.0 August------| 75.5 | 46.4 | 61.0 | 88 | 32 | 650 | 1.64 | 0.69 | 2.49 | 4 | 0.0 September---| 65.8 | 38.2 | 52.0 | 86 | 18 | 375 | 1.39 | 0.48 | 2.31 | 3 | 1.9 October-----| 55.6 | 29.6 | 42.6 | 77 | 1 | 168 | 1.13 | 0.48 | 1.72 | 3 | 1.2 November----| 41.1 | 18.6 | 29.8 | 67 | -14 | 32 | 0.75 | 0.30 | 1.11 | 2 | 4.5 December----| 35.4 | 12.1 | 23.8 | 58 | -28 | 8 | 0.56 | 0.20 | 0.89 | 2 | 5.5 | | | | | | | | | | | Yearly: | | | | | | | | | | | Average---| 53.6 | 28.3 | 40.9 | ——— | ——— | ——— | ——— | ——— | ——— | ——— | ——— Extreme---| 93.0 | -45.0 | ——— | 90 | -34 | ——— | ——— | ——— | ——— | ——— | ——— Total-----| ——— | ——— | ——— | ——— | ——— | 2,736 | 17.60 |14.12 | 20.96 | 44 | 44.7 ______| | | | | | | | | | |

* A growing-degree day is a unit of heat available for plant growth. It can be calculated by adding the maximum and minimum daily temperatures, dividing the sum by 2, and subtracting the temperature below which growth is minimal for the principal crops in the area (40 degrees F). Sweet Grass County Area, Montana—Part I 15

Freeze Dates in Spring and Fall

(Recorded in the period 1971 through 2000 at Big Timber and Melville)

______| | Temperature |______Probability | | | | 24 Degrees F | 28 Degrees F | 32 Degrees F | or Lower | or Lower | or Lower ______| | | | | | BIG TIMBER: | | | | | | Last freezing temperature | | | in spring: January-July | | | | | | 1 year in 10 later than-----| May 3 | May 18 | May 30 | | | 2 years in 10 later than----| April 28 | May 13 | May 26 | | | 5 years in 10 later than----| April 19 | May 3 | May 17 | | | First freezing temperature | | | in fall: August-December | | | | | | 1 year in 10 earlier than---| September 23 | September 17 | September 4 | | | 2 years in 10 earlier than--| September 28 | September 21 | September 9 | | | 5 years in 10 earlier than--| October 9 | September 29 | September 18 | | | | | | MELVILLE: | | | | | | Last freezing temperature | | | in spring: January-July | | | | | | 1 year in 10 later than-----| May 20 | June 3 | June 29 | | | 2 years in 10 later than----| May 14 | May 30 | June 22 | | | 5 years in 10 later than----| May 5 | May 21 | June 10 | | | First freezing temperature | | | in fall: August-December | | | | | | 1 year in 10 earlier than---| September 15 | September 5 | August 24 | | | 2 years in 10 earlier than--| September 19 | September 9 | August 29 | | | 5 years in 10 earlier than--| September 28 | September 18 | September 8 ______| | | 16

Growing Season

(Recorded in the period 1971 through 2000 at Big Timber and Melville)

______| | Daily Minimum Temperature |______Probability | | | | Higher Than | Higher Than | Higher Than | 24 Degrees F | 28 Degrees F | 32 Degrees F ______| | | | Days | Days | Days | | | BIG TIMBER: | | | | | | 9 years in 10------| 148 | 127 | 103 | | | 8 years in 10------| 156 | 134 | 110 | | | 5 years in 10------| 171 | 148 | 123 | | | 2 years in 10------| 187 | 161 | 136 | | | 1 year in 10------| 195 | 168 | 143 | | | | | | MELVILLE: | | | | | | 9 years in 10------| 126 | 101 | 64 | | | 8 years in 10------| 133 | 107 | 73 | | | 5 years in 10------| 145 | 118 | 88 | | | 2 years in 10------| 157 | 130 | 104 | | | 1 year in 10------| 163 | 136 | 113 ______| | | 17

Formation and Classification of the Soils

This section relates the soils in the survey area to Climate indirectly affects soil formation through its the major factors of soil formation and describes the effect on the kind and amount of living organisms on system of soil classification. The tables, and in the soil. Vegetation and organisms decay to “Classification of the Soils” and “Acreage and produce organic matter in the soil. Soils that have Proportionate Extent of the Soils,” at the end of this cool temperatures and high precipitation generally section show the classification and extent of the soils contain more organic matter and are dark colored. in this survey area. Soils that have warm temperatures and low precipitation generally contain less organic matter Formation of the Soils and are light colored. Soils form in rocks that have been broken into Soil is a natural, three-dimensional body on the suitable materials by erosion and alternate freezing earth’s surface. Soil has properties that result from and thawing. Chemical reactions, such as solution the integrated effect of climate and living matter and hydration, further break down this weathered acting on earthy parent material, as conditioned by material. relief over a period of time. Although there are many different soils, each soil Living Organisms is the result of the interaction of the same five factors. These factors are the effect of climate on the parent Living organisms are active in the formation of material, the kinds of plants and organisms living in soils. Plants, animals, insects, and microorganisms the soil, the relief of the land, the physical and affect gains or losses in organic matter, plant chemical composition of the parent material, and the nutrients in the soil, and changes in porosity and length of time it took for the soil to form. structure. Within short distances, the combination of these The kinds and amounts of living organisms are factors varies, and, consequently, the soils that form determined by soil-forming factors, such as climate differ in fertility, productivity, and physical and and topography. On the plains of Sweet Grass chemical characteristics. In the following paragraphs, County, grasses and forbs are the dominant the factors of soil formation are discussed as vegetation. At higher elevations and on portions of they relate to the soils in the Sweet Grass County the Yellowstone River breaks, coniferous trees with Area. woody plants, forbs, and grass undergrowth are dominant. Climate Roots, rodents, and insects penetrate the soil and alter its structure. The deep, fibrous root system of Temperature and precipitation mainly determine grasses improves the porosity and structure of the climate, an active force in the formation of soils. The soil. Because of this porosity, the activity of microbes, Sweet Grass County Area has a subhumid to earthworms, and burrowing animals increases. semiarid continental climate strongly influenced by Animals, in turn, increase porosity by burrowing close proximity to high-elevation mountains. The through the soil and leaving open channels for the climate is characterized by wide seasonal variations movement of water and air. Deep roots transport in temperature and wide local variations in minerals and plant nutrients to the surface, thus temperature and precipitation. The mean annual improving fertility. Under coniferous trees, needles temperature ranges from 35 to 45 degrees F, and the that drop to the soil surface increase the acidity of the average annual rainfall ranges from 14 to 25 inches soil. in the survey area. The average growing season Some organisms in the soil take in nitrogen from ranges from 50 to 125 days. the air and incorporate it into plant tissues. After 18 Soil Survey

these organisms die, the nitrogen is released in by the runoff on steeper soils also restricts the various forms and becomes available to plants. formation of distinct soil horizons. Soils under forest plants tend to be cooler than soils under grassland plants. Wet soils have less Parent Material oxygen available to microbes than drier soils. The activity of microorganisms and animals is less Parent material is the unconsolidated mass in extensive in cooler, wetter soils. As a result, organic which a soil forms. It strongly affects the chemical matter is broken down more slowly and more organic and mineralogical composition of the soil. The soils in litter remains on the surface of the soil. the Sweet Grass County Area formed in many different kinds of parent materials. The major Topography materials are recent alluvium, glacial alluvium, mixed alluvium and colluvium, soft bedrock, hard bedrock, Topography, or relief, is determined by glaciation and volcanic mudflows. and mountain formation and by the age and Recent alluvium is water-deposited material on the resistance of geologic formations to erosion by wind bottomlands and low terraces along the major and water. Topography influences soil development streams and rivers. These soils contain varying through its effect on drainage and runoff. The degree amounts of sand, silt, and clay. Many of them contain of slope, shape of the land surface, and permeability rounded gravel, cobbles, and stones. Soils formed on of the soil determine the rate of runoff, internal these positions lack significant soil development; they drainage, and moisture content of the soil. tend to be stratified. Many soils are still subject to Relief features in Sweet Grass County have been flooding. Havre and Ledger soils formed in alluvium determined by glaciation, geological uplift, volcanic on bottomlands. Kobase and Korchea soils formed on action, and removal and deposition of materials by low stream terraces. wind and water. The slopes in Sweet Grass County Glacial alluvium is material deposited by glacial range from 1 percent on bottomlands and terraces to melt water. This material is on terraces and outwash over 60 percent on mountainsides and breaks along plains throughout the county. The deposits range drainageways. from Pleistocene to Miocene Ages. These soils The number and distinctness of soil horizons contain varying amounts of sand, silt, and clay with generally decrease as slope increases. Soils on large amounts of gravel and cobbles. The soils steep slopes with rapid runoff have many formed in these materials generally have good characteristics similar to those of soils formed in arid horizon development. Roy and Shawmut soils are climates. Soils on east- and north-facing slopes have examples of soils formed in these materials. cooler temperatures than those on west- and south- Mixed alluvium and colluvium have been deposited facing slopes. East- and north-facing slopes receive by the combined forces of gravity and water. They less sunlight. As a result, the soils on these slopes consist of materials that have been moved downslope retain water longer and are cooler than soils on west- from higher areas and redeposited on footslopes, and south-facing slopes. The surface soil is darker alluvial fans, and along drainageways. They contain and the depth to lime is generally deeper on north- varying amounts of silt and clay with lesser amounts facing slopes than on south-facing slopes. In some of sand. Soils formed in these materials show varying parts of the survey area, these differences are degrees of development, depending upon the other pronounced. Soils formed only on east- and north- soil-forming factors. Shambo and Yamacall soils are facing slopes include Vision soils. These soils differ examples of soils from these materials with slight from the Winkler soils that formed in similar material horizon development. Farnuf and Work soils show on south-facing slopes. good horizon development. The soil horizons on gently sloping surfaces are Material weathered from soft bedrock formations is generally more distinct than soils formed in similar a major parent material in the uplands in this survey parent material on steep and very steep surfaces. area. Most of these materials are calcareous. The Gently sloping soils absorb more moisture, and water soils formed in place, or they formed in material that is retained in the soil to a greater depth. Soils on was locally reworked and transported by water and steeper slopes generally have a thinner, lighter wind. These deposits range in thickness from a few colored surface layer and a shallower depth to lime inches to several feet over the underlying bedrock. than soils formed on lesser slopes. Erosion caused Most soils formed in this material have weakly Sweet Grass County Area, Montana—Part I 19

expressed horizons. Cabba, Delpoint, Doney, and The Shambo soil formed in parent material that is Yawdim soils formed in this material. Some soils, similar to the parent material of the Havre soil but is such as Marmarth and Tanna, show good profile older. The soil material has been in place longer and development. time has had longer to on this soil. The surface layer Material weathered from hard sandstone is is darker and thicker than the Havre soil, and lime another parent material for many upland soils. These has been leached out of the surface soil. This soil has deposits range from a few inches to a little over a foot very little subsoil development. in thickness. They formed in place and include large The Farnuf soil is an example of a mature soil. It amounts of angular sandstone channers. Soils has extensive alteration of the subsoil. Fine clay formed in this material typically have weakly particles have moved out of the surface soil and have expressed horizons. Castner and Reedpoint soils been deposited in the subsoil. Lime and soluble formed in this material. minerals have been leached out of the subsoil and Volcanic mudflows are extensive in the uplands are redeposited in a layer of increased lime content south of the Yellowstone River. The material is of below the subsoil. The passage of time has affected a Cretaceous Age. These materials weathered in place great deal of change in the original water lain parent or they formed in material locally reworked and material. redeposited by gravity, wind, and water. The deposits Many of the sloping and steep, shallow, and very range in thickness from a few inches to several feet. shallow soils appear to have been in the process of The material is not calcareous and consists of formation for about as long as some of the more varying amounts of silt and sand with lesser amounts developed, less sloping soils. However, erosion has of clay. Examples of soils formed in this material removed the soil as fast as it formed. In this case, the include the Ashbon, Sweetweed, and Weedzunit effect of time has been offset by the effect of relief. soils. Classification of the Soils Time The system of soil classification used by the Change taking place in soils over a long period is National Cooperative Soil Survey has six categories called soil genesis. As a result of these changes, (Soil Survey Staff, 1998 and 1999). Beginning with distinct horizons, or layers, develop in the soils. The the broadest, these categories are the order, length of time that parent materials have been in suborder, great group, subgroup, family, and series. place and exposed to climate and living organisms is Classification is based on soil properties observed in generally reflected in the degree to which the soil the field or inferred from those observations or from profile has developed. The kind and arrangement of laboratory measurements. The table, “Classification these horizons are called soil morphology. These of the Soils,” shows the classification of the soils in layers are described in terms of chemistry, color, the survey area. The categories are defined in the consistence, permeability, structure, texture, and following paragraphs. thickness. ORDER. Twelve soil orders are recognized. The Soils are classified according to their approximate differences among orders reflect the dominant soil- age, from young to mature. Age, or maturity, of a soil forming processes and the degree of soil formation. is generally indicated by the thickness and Each order is identified by a word ending in sol. An distinctness of subsurface horizons, content of example is Mollisol, from mollis, meaning soft. organic matter and clay, depth to which soluble SUBORDER. Each order is divided into suborders material is leached, and form and distribution of primarily on the basis of properties that influence soil calcium carbonate and gypsum in the soil. genesis and are important to plant growth or Young soils show very little profile development. properties that reflect the most important variables Havre soils are considered a young soil. They are on within the orders. The last syllable in the name of a flood plains and are inundated by water at some suborder indicates the order. An example is Ustoll times. The parent material has been in place for a (Ust, meaning burnt, plus oll, from Mollisol). short time. This soil has little accumulation of organic GREAT GROUP. Each suborder is divided into matter, and there has been no clay movement within great groups on the basis of close similarities in kind, the soil. The soil profile has thin strata of water lain arrangement, and degree of development of material that has not been altered, and the soil is limy pedogenic horizons; soil moisture and temperature up to the surface. regimes; type of saturation; and base status. Each 20 Soil Survey

great group is identified by the name of a suborder range of important characteristics of the soils in the and by a prefix that indicates a property of the soil. series. An example is Argiustoll (Argi, meaning having an argillic horizon or clay accumulation, plus ustoll, the suborder of the Mollisols that has a dry climate). Absarokee Series SUBGROUP. Each great group has a typic Depth class: Moderately deep (20 to 40 inches) subgroup. Other subgroups are intergrades or Drainage class: Well drained extragrades. The typic subgroup is the central Permeability: Moderately slow (0.2 to 0.6 inch/hour) concept of the great group; it is not necessarily the Landform: Escarpment, hill, structural bench, terrace, most extensive. Intergrades are transitions to other and swale on plain orders, suborders, or great groups. Extragrades have Parent material: Silty and clayey residuum weathered some properties that are not representative of the from sandstone and shale great group but do not indicate transitions to any Slope range: 0 to 45 percent other taxonomic class. Each subgroup is identified by Elevation range: 3,900 to 6,000 feet one or more adjectives preceding the name of the Mean annual precipitation: 15 to 20 inches great group. The adjective Typic identifies the Mean annual air temperature: 39 to 45 degrees F subgroup that typifies the great group. An example is Frost-free period: 70 to 125 days Typic Argiustolls. FAMILY. Families are established within a Taxonomic Class: Fine, smectitic, frigid Typic subgroup on the basis of physical and chemical Argiustolls properties and other characteristics that affect management. Generally, the properties are those of Typical Pedon horizons below plow depth where there is much Absarokee loam, in an area of Absarokee-Amherst biological activity. Among the properties and complex, 2 to 8 percent slopes, in an area of characteristics considered are particle-size class, rangeland, 1,200 feet south and 1,700 feet east of the mineralogy class, cation-exchange activity class, soil northwest corner of sec. 27, T. 2 S., R. 17 E.; USGS temperature regime, soil depth, and reaction class. A Reed Point topographic quadrangle (lat. 45o38'06" N.; family name consists of the name of a subgroup long. 109o37'01" W.) preceded by terms that indicate soil properties. An example is fine-loamy, mixed, superactive, frigid Typic A1—0 to 4 inches; grayish brown (10YR 5/2) loam, Argiustolls. very dark brown (10YR 2/2) moist; weak medium SERIES. The series consists of soils within a family platy structure parting to moderate fine granular; that have horizons similar in arrangement in the soft, very friable, slightly sticky, slightly plastic; profile, color, consistence, mineral and chemical common very fine and fine roots; common very composition, reaction, structure, and texture. An fine pores; neutral (pH 6.8); clear smooth example is the Farnuf series. The soils in the Farnuf boundary. series are fine-loamy, mixed, superactive, frigid Typic A2—4 to 8 inches; brown (10YR 5/3) silty clay loam, Argiustolls. dark brown (10YR 3/3) moist; weak fine and moderate very fine subangular blocky structure; Soil Series and Their Morphology slightly hard, friable, moderately sticky, moderately plastic; common very fine and fine In this section, each soil series recognized in the roots; few fine and common very fine pores; survey area is described. Characteristics of the soil neutral (pH 6.6); clear smooth boundary. and the material in which it formed are identified for Bt1—8 to 14 inches; brown (10YR 5/3) clay loam, each series. A pedon, a small three-dimensional area brown (10YR 4/3) moist; moderate fine of soil, that is typical of the series in the survey area, subangular blocky structure; slightly hard, friable, is described. The detailed description of each soil very sticky, very plastic; common very fine roots; horizon follows standards in the “Soil Survey Manual” common fine pores; common distinct brown (Soil Survey Division Staff, 1993). Many of the (7.5YR 4/4) moist; clay films on faces of peds; technical terms used in the descriptions are defined neutral (pH 6.6); gradual wavy boundary. in “Soil Taxonomy” (Soil Survey Staff, 1999) and in Bt2—14 to 23 inches; yellowish brown (10YR 5/4) “Keys to Soil Taxonomy” (Soil Survey Staff, 1998). clay loam, dark yellowish brown (10YR 4/4) Unless otherwise indicated, colors in the descriptions moist; weak medium and moderate fine are for dry soil. Following the pedon description is the subangular blocky structure; moderately hard, Sweet Grass County Area, Montana—Part I 21

friable, very sticky, very plastic; common very fine Content of rock fragments: 0 to 10 percent—0 to roots; common fine pores; common distinct 5 percent stones and cobbles; 0 to 5 percent strong brown (7.5YR 4/6) moist; clay films on gravel or channers faces of peds; neutral (pH 6.8); clear wavy Reaction: pH 6.6 to 8.4 boundary. Bk horizon Bk—23 to 26 inches; pale brown (10YR 6/3) loam, Hue: 7.5YR, 10YR, or 2.5Y yellowish brown (10YR 5/4) moist; weak medium Value: 6 to 8 dry; 5 to 7 moist prismatic structure parting to weak medium Chroma: 2 to 4 subangular blocky; slightly hard, friable, Texture (less than 2 mm): Loam or clay loam moderately sticky, moderately plastic; common Clay content: 25 to 40 percent very fine roots; few fine pores; few fine soft Content of rock fragments: 0 to 35 percent—0 to masses of lime; strongly effervescent; moderately 5 percent stones and cobbles; 0 to 30 percent alkaline (pH 8.0); clear wavy boundary. gravel or channers Cr—26 to 60 inches; interbedded semiconsolidated Calcium carbonate equivalent: 15 to 25 percent shale and hard sandstone; slightly effervescent. Reaction: pH 7.4 to 9.0 Range in Characteristics Soil temperature: 41 to 47 degrees F Absher Family Moisture control section: Between 4 and 12 inches Thickness of the mollic epipedon: 7 to 12 inches Depth class: Very deep (greater than 60 inches) Depth to the Bk horizon: 12 to 30 inches Drainage class: Somewhat poorly drained Depth to the Cr horizon: 20 to 40 inches Permeability: Very slow (less than 0.06 inch/hour) Landform: Flood plain and stream terrace A horizons Parent material: Silty and clayey alluvium Hue: 7.5YR, 10YR, or 2.5Y Slope range: 0 to 8 percent Value: 4 or 5 dry; 2 or 3 moist Elevation range: 3,750 to 5,200 feet Chroma: 2 or 3 Mean annual precipitation: 10 to 14 inches Texture (less than 2 mm): Loam, clay loam, or Mean annual air temperature: 40 to 45 degrees F silty clay loam Frost-free period: 95 to 125 days Clay content: 20 to 35 percent Content of rock fragments: 0 to 35 percent—0 to Taxonomic Class: Fine, smectitic, frigid Leptic 10 percent stones and cobbles; 0 to 25 percent Torrertic Natrustalfs gravel or channers Reaction: pH 6.1 to 7.3 Typical Pedon Bt1 horizon Absher clay (when mixed), in an area of Soapcreek- Hue: 7.5YR, 10YR, or 2.5Y Absher family complex, 0 to 4 percent slopes, in an Value: 5 or 6 dry; 4 or 5 moist area of rangeland, 2,000 feet south and 1,200 feet Chroma: 2 to 4 east of the northwest corner of sec. 18, T. 4 N., Texture (less than 2 mm): Clay loam, clay, or silty R. 15 E.; USGS Melville topographic quadrangle clay (lat. 46o05'54" N.; long. 109o54'35" W.) Clay content: 35 to 50 percent E—0 to .5 inch; light brownish gray (10YR 6/2) silty Content of rock fragments: 0 to 10 percent—0 to clay loam, dark grayish brown (10YR 4/2) moist; 5 percent stones and cobbles; 0 to 5 percent weak thin platy structure parting to weak fine and gravel or channers medium granular; moderately hard, friable, Reaction: pH 6.6 to 8.4 moderately sticky, moderately plastic; common Bt2 horizon very fine roots; common very fine pores; slightly Hue: 7.5YR, 10YR, or 2.5Y effervescent; moderately alkaline (pH 8.4); abrupt Value: 5 or 6 dry; 4 or 5 moist broken boundary. Chroma: 3 or 4 Btn—.5 to 4 inches; grayish brown (10YR 5/2) clay, Texture (less than 2 mm): Clay loam, clay, or silty very dark grayish brown (10YR 4/2) moist; strong clay coarse columnar structure parting to moderate Clay content: 35 to 50 percent medium and coarse angular blocky; very hard, 22 Soil Survey

firm, very sticky, very plastic; common very fine plastic; disseminated lime; 30 percent gravel; roots; common very fine pores; continuous violently effervescent; moderately alkaline distinct dark grayish brown (2.5Y 4/2) moist; clay (pH 8.0). films on faces of peds and lining pores; common discontinuous black (10YR 2/1), moist, organic Range in Characteristics coats on faces of peds and in pores; slightly Soil temperature: 42 to 47 degrees F effervescent; very strongly alkaline (pH 9.6); Moisture control section: Between 4 and 12 inches abrupt smooth boundary. Depth to the seasonal high water table: 18 to Btn2—4 to 9 inches; grayish brown (10YR 5/2) clay, 36 inches dark gray (10YR 4/1) moist; strong fine and Depth to the Btkgnyz horizon: 6 to 20 inches medium angular blocky structure; very hard, firm, very sticky, very plastic; common very fine and E horizon fine roots; common very fine pores; few distinct Hue: 10YR or 2.5Y patchy dark yellowish brown (10YR 3/4) moist; Value: 6 or 7 dry; 3 to 5 moist clay films on faces of peds and lining pores; Chroma: 1 to 3 strongly effervescent; very strongly alkaline Texture (less than 2 mm): Silty clay loam, loam, (pH 9.6); clear smooth boundary. silt loam, or fine sandy loam Btkgnyz—9 to 19 inches; light olive gray (5Y 6/2) clay Clay content: 15 to 35 percent loam, olive gray (5Y 5/2) moist; moderate Content of rock fragments: 0 to 35 percent—0 to medium and coarse angular blocky structure; 5 percent cobbles; 0 to 30 percent gravel very hard, firm, moderately sticky, moderately Electrical conductivity: 4 to 8 mmhos/cm plastic; few very fine and fine roots; common very Sodium adsorption ratio: 1 to 5 fine pores; few distinct patchy dark yellowish Reaction: pH 6.6 to 8.4 brown (10YR 3/4), moist; clay films on faces of Btn horizons peds and lining pores; many fine masses of lime; Hue: 2.5Y or 10YR common fine crystals of gypsum and other salts; Value: 4 to 6 dry; 4 or 5 moist 3 percent gravel; strongly effervescent; strongly Chroma: 1 to 3 alkaline (pH 8.6); clear smooth boundary. Texture (less than 2 mm): Clay, silty clay, or clay Bkgyz1—19 to 33 inches; olive gray (5Y 5/2) clay loam loam, olive gray (5Y 4/2) moist; common medium Clay content: 35 to 60 percent and coarse prominent light olive brown (2.5Y 5/6) Structure: Moderate or strong columnar or moist, redox concentrations; weak coarse prismatic prismatic structure; very hard, firm, moderately Consistence: Very hard or extremely hard when sticky, moderately plastic; few very fine and fine dry roots; many fine and medium masses of lime; Content of rock fragments: 0 to 15 percent gravel common fine crystals of gypsum and other salts; Electrical conductivity: 8 to 16 mmhos/cm 7 percent gravel; strongly effervescent; Sodium adsorption ratio: 18 to 50 moderately alkaline (pH 8.0); clear smooth Reaction: pH 6.6 to 9.6 boundary. Bkgyz2—33 to 44 inches; light gray (5Y 7/2) gravelly Btkgnyz horizon sandy clay loam, olive gray (5Y 5/2) moist; Hue: 10YR, 2.5Y, or 5Y common medium prominent light olive brown Value: 4 to 6 dry; 4 or 5 moist (2.5Y 5/6) moist, redox concentrations; massive; Chroma: 2 or 3 moderately hard, friable, moderately sticky, Texture (less than 2 mm): Clay loam, clay, or silty moderately plastic; many fine and medium clay masses of lime; few fine crystals of gypsum and Clay content: 35 to 50 percent other salts; 25 percent gravel; violently Content of rock fragments: 0 to 20 percent gravel effervescent; moderately alkaline (pH 8.0); Calcium carbonate equivalent: 5 to 15 percent gradual smooth boundary. Electrical conductivity: 8 to 32 mmhos/cm BCkg—44 to 60 inches; light gray (5Y 7/1) gravelly Sodium adsorption ratio: 18 to 50 sandy loam, olive gray (5Y 5/2) moist; massive; Gypsum content: 1 to 5 percent moderately hard, friable, slightly sticky, slightly Reaction: pH 7.9 to 9.6 Sweet Grass County Area, Montana—Part I 23

Bkgyz horizons many unstained sand grains; neutral (pH 6.6); Hue: 10YR, 5Y, or 2.5Y abrupt wavy boundary. Value: 5 to 7 dry; 4 to 6 moist Btn1—1 to 5 inches; grayish brown (2.5Y 5/2) silty Chroma: 2 to 4 clay, dark grayish brown (2.5Y 4/2) moist; strong Texture (less than 2 mm): Clay loam, sandy clay medium columnar structure; extremely hard, firm, loam, clay, or silty clay moderately sticky, moderately plastic; many very Clay content: 27 to 50 percent fine and fine roots; few medium and many very Content of rock fragments: 0 to 20 percent gravel fine and fine pores; few faint uncoated sand Calcium carbonate equivalent: 5 to 15 percent grains on vertical faces of peds; continuous Electrical conductivity: 8 to 32 mmhos/cm distinct clay films on faces of peds; slightly Sodium adsorption ratio: 18 to 50 alkaline (pH 7.7); clear wavy boundary. Gypsum content: 1 to 5 percent Btn2—5 to 11 inches; grayish brown (2.5Y 5/2) silty Reaction: pH 7.9 to 9.6 clay, dark grayish brown (2.5Y 4/2) moist; strong medium prismatic structure parting to strong fine BCkg horizon and medium angular blocky; extremely hard, Hue: 2.5Y or 5Y firm, moderately sticky, moderately plastic; many Value: 5 to 7 dry; 4 to 6 moist very fine and fine roots; many very fine and fine Chroma: 1 or 2 pores; continuous distinct clay films on faces of Texture (less than 2 mm): Sandy clay loam, clay peds; slightly effervescent; moderately alkaline loam, or sandy loam (pH 8.3); clear wavy boundary. Clay content: 18 to 35 percent Btknyz—11 to 16 inches; grayish brown (2.5Y 5/2) Content of rock fragments: 5 to 35 percent gravel silty clay, dark grayish brown (2.5Y 4/2) moist; Calcium carbonate equivalent: 5 to 15 percent strong fine and medium subangular blocky Electrical conductivity: 8 to 32 mmhos/cm structure; extremely hard, friable, moderately Reaction: pH 7.9 to 9.6 sticky, moderately plastic; many very fine and fine roots; many very fine and fine pores; continuous distinct clay films on faces of peds; few very fine Absher Series masses of lime; common fine and medium crystals of gypsum and other salts; strongly Depth class: Very deep (greater than 60 inches) effervescent; strongly alkaline (pH 8.8); clear Drainage class: Well drained wavy boundary. Permeability: Very slow (less than 0.06 inch/hour) Bknyz—16 to 32 inches; grayish brown (2.5Y 5/2) Landform: Plain and stream terrace silty clay, dark grayish brown (2.5Y 4/2) moist; Parent material: Silty and clayey alluvium massive; extremely hard, firm, moderately sticky, Slope range: 0 to 8 percent moderately plastic; many very fine and fine roots Elevation range: 3,750 to 5,200 feet and pores; many medium and coarse crystals of Mean annual precipitation: 10 to 14 inches gypsum and other salts; common fine threads of Mean annual air temperature: 40 to 45 degrees F lime; disseminated lime; strongly effervescent; Frost-free period: 95 to 125 days strongly alkaline (pH 8.8); clear wavy boundary. Bkyz1—32 to 42 inches; grayish brown (2.5Y 5/2) Taxonomic Class: Fine, smectitic, frigid Leptic silty clay, dark grayish brown (2.5Y 4/2) moist; Torrertic Natrustalfs massive; extremely hard, firm, moderately sticky, Typical Pedon moderately plastic; common very fine and fine roots; few medium and many very fine and fine Absher silty clay (when mixed), 2,580 feet north and pores; common fine crystals of gypsum and other 2,520 feet east of the southwest corner of sec. 17, salts; few fine threads of lime; disseminated lime; T. 19 N., R. 1 E.; Cascade County, Montana. slightly effervescent; strongly alkaline (pH 8.5); E—0 to 1 inch; light brownish gray (2.5Y 6/2) loam, diffuse wavy boundary. very dark grayish brown (2.5Y 3/2) moist; Bkyz2—42 to 60 inches; very pale brown (10YR 7/3) moderate very thin platy structure parting to clay, grayish brown (2.5Y 5/2) and brown (10YR moderate very fine and fine granular; soft, very 5/3) moist; silt loam varves that are massive and friable, slightly sticky, slightly plastic; many very average 1 centimeter in thickness; extremely fine and fine roots; many very fine and fine pores; hard, firm, moderately sticky, moderately plastic; 24 Soil Survey

few very fine and fine roots; few very fine and fine Bknyz and Bkyz horizons crystals of gypsum and other salts; few fine Hue: 2.5Y, 10YR, or 7.5YR threads of lime; disseminated lime; slightly Value: 5 to 7 dry; 4 to 6 moist effervescent; strongly alkaline (pH 8.5). Chroma: 2 to 4 Texture (less than 2 mm): Clay loam, sandy clay Range in Characteristics loam, silty clay, clay, or silty clay loam Clay content: 27 to 45 percent Soil temperature: 42 to 47 degrees F (60 to Content of rock fragments: 0 to 20 percent gravel 68 degrees F in summer) Calcium carbonate equivalent: 5 to 15 percent Moisture control section: Between 4 and 12 inches Electrical conductivity: 8 to 32 mmhos/cm Depth to the Btknyz horizon: 6 to 20 inches Sodium adsorption ratio: 18 to 50 E horizon Gypsum content: 1 to 5 percent Hue: 2.5Y, 10YR, or 7.5YR Reaction: pH 7.9 to 9.6 Value: 6 or 7 dry; 3 to 5 moist Chroma: 1 to 3 Texture (less than 2 mm): Loam, silt loam, or fine Adel Series sandy loam (Where mixed with the Bt horizon, Depth class: Very deep (greater than 60 inches) textures are mainly silty clay loam, clay loam, Drainage class: Well drained silty clay, clay, silt loam, or sandy clay loam.) Permeability: Moderate (0.6 to 2.0 inches/hour) Clay content: 15 to 55 percent Landform: Swale on fan, drainageway on mountain, Content of rock fragments: 0 to 35 percent—0 to fan on mountain, and swale on mountain 5 percent cobbles; 0 to 30 percent gravel Parent material: Loamy alluvium or colluvium Electrical conductivity: 4 to 8 mmhos/cm Slope range: 2 to 45 percent Reaction: pH 6.6 to 8.4 Elevation range: 5,500 to 7,500 feet Btn horizons Mean annual precipitation: 20 to 25 inches Hue: 2.5Y, 7.5YR, or 10YR Mean annual air temperature: 35 to 44 degrees F Value: 4 to 6 dry; 4 or 5 moist Frost-free period: 50 to 70 days Chroma: 1 to 3 Texture (less than 2 mm): Silty clay, clay, or clay Taxonomic Class: Fine-loamy, mixed, superactive loam Pachic Haplocryolls Clay content: 35 to 60 percent Typical Pedon Structure: Moderate or strong columnar or prismatic Adel loam, in an area of Adel-Timberlin complex, 8 to Consistence: Very hard or extremely hard when 35 percent slopes, in an area of deciduous forest, dry 400 feet south and 2,100 feet west of the northeast Content of rock fragments: 0 to 15 percent gravel corner of sec. 13, T. 3 S., R. 13 E.; USGS Squaw Electrical conductivity: 8 to 16 mmhos/cm Peak topographic quadrangle (lat. 45o34'53" N.; long. Sodium adsorption ratio: 18 to 50 110o03'41" W.) Reaction: pH 6.6 to 9.6 A1—0 to 12 inches; very dark gray (10YR 3/1) loam, Btknyz horizon black (10YR 2/1) moist; strong fine granular Hue: 2.5Y, 10YR, or 7.5YR structure; slightly hard, friable, slightly sticky, Value: 4 to 6 dry; 4 or 5 moist slightly plastic; few medium and coarse and many Chroma: 2 or 3 very fine and fine roots; many very fine and fine Texture (less than 2 mm): Clay loam, clay, or silty pores; 5 percent gravel; neutral (pH 6.6); clear clay smooth boundary. Clay content: 35 to 50 percent A2—12 to 23 inches; very dark grayish brown (10YR Content of rock fragments: 0 to 20 percent gravel 3/2) loam, very dark brown (10YR 2/2) moist; Calcium carbonate equivalent: 5 to 15 percent moderate fine granular structure; soft, friable, Electrical conductivity: 8 to 32 mmhos/cm slightly sticky, slightly plastic; few coarse and Sodium adsorption ratio: 18 to 50 common fine and medium roots; many very fine Gypsum content: 1 to 5 percent and fine pores; 5 percent gravel; slightly acid Reaction: pH 7.9 to 9.6 (pH 6.4); clear smooth boundary. Sweet Grass County Area, Montana—Part I 25

A3—23 to 37 inches; dark gray (10YR 4/1) loam, very Content of rock fragments: 0 to 35 percent—0 to dark gray (10YR 3/1) moist; weak fine granular 5 percent stones and cobbles; 0 to 30 percent structure; soft, very friable, slightly sticky, slightly gravel plastic; few very fine and medium and common Reaction: pH 6.1 to 7.8 fine roots; many very fine and fine pores; Bw horizons 10 percent gravel; slightly acid (pH 6.4); clear Hue: 2.5Y or 10YR smooth boundary. Value: 4 or 5 dry; 2 to 4 moist Bw1—37 to 48 inches; grayish brown (10YR 5/2) Chroma: 1 to 3 loam, very dark grayish brown (10YR 3/2) moist; Texture (less than 2 mm): Loam, clay loam, or weak medium and coarse subangular blocky silty clay loam structure; slightly hard, friable, slightly sticky, Clay content: 18 to 30 percent slightly plastic; few very fine to coarse roots; Content of rock fragments: 0 to 35 percent—0 to common medium and many very fine and fine 10 percent stones and cobbles; 0 to 25 percent pores; 5 percent gravel; slightly acid (pH 6.4); gravel clear smooth boundary. Calcium carbonate equivalent: 0 to 5 percent Bw2—48 to 60 inches; grayish brown (10YR 5/2) Reaction: pH 6.1 to 7.8 loam, dark grayish brown (10YR 4/2) moist; weak coarse subangular blocky structure; slightly hard, friable, slightly sticky, slightly plastic; few fine to Albicalis Taxadjunct coarse roots; common very fine to medium pores; 10 percent gravel; slightly acid (pH 6.4). Depth class: Very deep (greater than 60 inches) Drainage class: Poorly drained Range in Characteristics Permeability: Moderate (0.6 to 2.0 inches/hour) Soil temperature: 36 to 46 degrees F Landform: Flood plain and drainageway on Moisture control section: Between 4 and 12 inches escarpment Thickness of the mollic epipedon: 16 to 60 inches Parent material: Fine-loamy alluvium Slope range: 0 to 4 percent A1 horizon Elevation range: 3,750 to 6,000 feet Hue: 10YR or 2.5Y Mean annual precipitation: 10 to 19 inches Value: 2 to 4 dry; 2 or 3 moist Mean annual air temperature: 39 to 44 degrees F Chroma: 1 or 2 Frost-free period: 85 to 125 days Texture (less than 2 mm): Loam Clay content: 15 to 27 percent Taxonomic Class: Fine-loamy, mixed, superactive, Content of rock fragments: 0 to 35 percent—0 to calcareous, frigid Aeric Fluvaquents 5 percent stones and cobbles; 0 to 30 percent gravel Albicalis soils as mapped in this survey area are Reaction: pH 6.1 to 7.3 taxadjunct to the series. They are outside the series A2 horizon range with higher reaction and calcium carbonate Hue: 10YR or 2.5Y equivalent in the 10- to 20-inch calcareous and Value: 3 to 5 dry; 2 or 3 moist reaction class control section. Use and management Chroma: 1 to 3 are not significantly affected. Albicalis series Texture (less than 2 mm): Loam or clay loam classifies Fine-loamy, mixed, superactive, nonacid, Clay content: 18 to 30 percent frigid Aeric Fluvaquents. Content of rock fragments: 0 to 35 percent—0 to Typical Pedon 5 percent stones and cobbles; 0 to 30 percent gravel Albicalis loam, in an area of Korchea-Fairway- Reaction: pH 6.1 to 7.8 Albicalis loams, channeled, 0 to 4 percent slopes, in an area of rangeland, 500 feet south and 300 feet A3 horizon west of the northeast corner of sec. 14, T. 4 N., Hue: 10YR or 2.5Y R. 15 E.; USGS Upper Glasston Lake topographic Value: 3 to 5 dry; 2 or 3 moist quadrangle (lat. 46o06'10" N.; long. 109o48'48" W.) Chroma: 1 to 3 Texture (less than 2 mm): Loam or clay loam A—0 to 4 inches; dark grayish brown (10YR 4/2) Clay content: 18 to 30 percent loam, very dark grayish brown (10YR 3/2) moist; 26 Soil Survey

moderate fine granular structure; soft, very Cg1 horizon friable, slightly sticky, nonplastic; common fine to Hue: 10YR or 2.5Y coarse and many very fine roots; many very fine Value: 5 or 6 dry; 4 or 5 moist and fine pores; strongly effervescent; moderately Chroma: 2 or 3 alkaline (pH 8.4); abrupt smooth boundary. Redox concentrations: Common or many; chroma Cg1—4 to 14 inches; grayish brown (2.5Y 5/2) of 4 or 6 stratified loam and very fine sandy loam, dark Texture (less than 2 mm): Loam or clay loam with grayish brown (2.5Y 4/2) moist; common fine strata of silt loam, very fine sandy loam, loamy distinct strong brown (7.5YR 4/6) moist, redox sand, or loam concentrations; massive; soft, very friable, slightly Clay content: 18 to 35 percent, mixed sticky, nonplastic; common fine to coarse roots; Content of rock fragments: 0 to 15 percent gravel many very fine and fine pores; strongly Calcium carbonate equivalent: 0 to 10 percent effervescent; moderately alkaline (pH 8.4); clear Reaction: pH 7.4 to 8.4 smooth boundary. Cg2 and Cg3 horizons Cg2—14 to 42 inches; light brownish gray (2.5Y 6/2) Hue: 10YR or 2.5Y stratified loam, dark grayish brown (2.5Y 4/2) Value: 5 to 7 dry; 4 or 5 moist moist; common fine and medium distinct brown Chroma: 2 or 3 (7.5YR 4/4) moist, redox concentrations; massive; Redox concentrations: Common or many; chroma soft, very friable, slightly sticky, nonplastic; few of 4 or 6 medium and common very fine and fine roots; Texture (less than 2 mm): Loam, silt loam, or clay common very fine and fine pores; strongly loam with strata of silt loam, fine sandy loam, effervescent; moderately alkaline (pH 8.4); diffuse loam, or clay smooth boundary. Clay content: 18 to 35 percent, mixed Cg3—42 to 52 inches; light brownish gray (2.5Y 6/2) Content of rock fragments: 0 to 15 percent gravel stratified loam and fine sandy loam, dark grayish Calcium carbonate equivalent: 0 to 10 percent brown (2.5Y 4/2) moist; few fine faint strong Reaction: pH 7.4 to 8.4 brown (7.5YR 4/6) moist, redox concentrations; massive; soft, very friable, nonsticky, nonplastic; Cg4 horizon few very fine and fine roots; slightly effervescent; Hue: 10YR, 2.5Y, or 5Y moderately alkaline (pH 8.4); clear smooth Value: 5 or 6 dry; 3 to 5 moist boundary. Chroma: 1 or 2 Cg4—52 to 60 inches; gray (5Y 6/1) stratified loam, Redox concentrations: None to many; chroma of dark gray (5Y 4/1) moist; common fine and 4, 6, or 8 medium distinct strong brown (7.5YR 4/6) moist, Redox depletions: None to common; chroma of redox concentrations; massive; soft, very friable, 0 or 1 slightly sticky, slightly plastic; slightly effervescent; Texture (less than 2 mm): Loam or silty clay loam moderately alkaline (pH 8.4). with strata of silt loam, clay loam, and fine sandy loam Range in Characteristics Clay content: 18 to 35 percent, mixed Soil temperature: 41 to 47 degrees F Content of rock fragments: 0 to 15 percent gravel Moisture control section: Between 4 and 12 inches Calcium carbonate equivalent: 0 to 10 percent Depth to the seasonal high water table: 12 to Reaction: pH 7.4 to 8.4 24 inches A horizon Amherst Series Hue: 10YR or 2.5Y Value: 4 to 6 dry; 3 to 5 moist Depth class: Shallow (10 to 20 inches) Chroma: 1 or 2 Drainage class: Well drained Texture (less than 2 mm): Loam Permeability: Moderately slow (0.2 to 0.6 inch/hour) Clay content: 18 to 27 percent Landform: Escarpment, hill, structural bench, and Content of rock fragments: 0 to 15 percent gravel knoll on plain Calcium carbonate equivalent: 0 to 15 percent Parent material: Clayey residuum weathered from Reaction: pH 6.6 to 8.4 sandstone or andesite Sweet Grass County Area, Montana—Part I 27

Slope range: 2 to 45 percent Clay content: 27 to 35 percent Elevation range: 4,200 to 6,000 feet Content of rock fragments: 0 to 35 percent—0 to Mean annual precipitation: 15 to 19 inches 5 percent stones and cobbles; 0 to 30 percent Mean annual air temperature: 40 to 45 degrees F gravel or channers Frost-free period: 70 to 115 days Reaction: pH 6.6 to 7.8 Bt1 horizon Taxonomic Class: Clayey, smectitic, frigid Lithic Hue: 7.5YR, 10YR, or 2.5Y Argiustolls Value: 4 or 5 dry; 3 moist Typical Pedon Chroma: 2 or 3 Texture (less than 2 mm): Clay loam or loam Amherst gravelly clay loam, in an area of Castner- Clay content: 35 to 50 percent Amherst complex, 2 to 15 percent slopes, in an Content of rock fragments: 0 to 35 percent—0 to area of rangeland, 1,400 feet south and 1,700 feet 5 percent cobbles; 0 to 30 percent gravel or west of the northeast corner of sec. 26, T. 1 N., channers R. 12 E.; USGS Kelly Hills topographic quadrangle Reaction: pH 6.6 to 7.8 (lat. 45o48'37" N.; long. 110o11'41" W.) Bt2 horizon A—0 to 4 inches; brown (10YR 4/3) gravelly clay Hue: 7.5YR, 10YR, or 2.5Y loam; very dark grayish brown (10YR 3/2) moist; Value: 4 or 5 dry; 3 or 4 moist weak fine granular structure; slightly hard, very Chroma: 2 to 4 friable, moderately sticky, moderately plastic; Texture (less than 2 mm): Clay loam or clay common very fine to medium roots; many very Clay content: 35 to 50 percent fine and fine pores; 20 percent gravel; neutral Content of rock fragments: 15 to 35 percent—0 to (pH 7.2); clear smooth boundary. 5 percent cobbles; 15 to 30 percent gravel or Bt1—4 to 12 inches; brown (10YR 4/3) clay loam; channers dark brown (10YR 3/3) moist; moderate medium Reaction: pH 6.6 to 7.8 subangular blocky structure; moderately hard, friable, very sticky, very plastic; few fine and medium and common very fine roots; few fine Amor Series and common very fine pores; common faint dark yellowish brown (10YR 3/4) moist; clay films on Depth class: Moderately deep (20 to 40 inches) faces of peds; 5 percent gravel; neutral (pH 7.2); Drainage class: Well drained clear smooth boundary. Permeability: Moderate (0.6 to 2.0 inches/hour) Bt2—12 to 18 inches; brown (10YR 5/3) gravelly clay Landform: Escarpment, hill, and swale on plain loam; brown (10YR 4/3) moist; moderate medium Parent material: Loamy residuum weathered from subangular blocky structure; moderately hard, sandstone and siltstone friable, very sticky, very plastic; few very fine Slope range: 2 to 35 percent roots; common very fine pores; common faint Elevation range: 4,200 to 6,200 feet dark yellowish brown (10YR 3/4) moist; clay films Mean annual precipitation: 15 to 20 inches on faces of peds; 15 percent gravel; neutral Mean annual air temperature: 40 to 45 degrees F (pH 7.2); abrupt smooth boundary. Frost-free period: 70 to 115 days R—18 inches; hard fractured noncalcareous sandstone. Taxonomic Class: Fine-loamy, mixed, superactive, frigid Typic Haplustolls Range in Characteristics Typical Pedon Soil temperature: 42 to 47 degrees F Moisture control section: Between 4 and 12 inches Amor loam, in an area of Amor-Cabba loams, 2 to Thickness of the mollic epipedon: 7 to 12 inches 8 percent slopes, in an area of rangeland, 2,000 feet Depth to bedrock: 10 to 20 inches north and 2,400 feet east of the southwest corner of sec. 22, T. 4 N., R. 13 E.; USGS Battleship Butte A horizon quadrangle (lat. 46o04'51" N.; long. 110o05'35" W.) Hue: 7.5YR, 10YR, or 2.5Y Value: 4 or 5 dry; 2 or 3 moist A1—0 to 4 inches; dark grayish brown (10YR 4/2) Chroma: 2 or 3 loam, very dark grayish brown (10YR 3/2) moist; Texture (less than 2 mm): Clay loam weak fine and medium granular structure; soft, 28 Soil Survey

very friable, slightly sticky, slightly plastic; many A horizons very fine and fine roots; many very fine and fine Hue: 10YR pores; neutral (pH 7.0); clear smooth boundary. Value: 3 to 5 dry; 2 or 3 moist A2—4 to 7 inches; grayish brown (10YR 5/2) loam, Chroma: 2 or 3 dark brown (10YR 3/3) moist; weak fine Texture (less than 2 mm): Loam subangular blocky structure parting to weak very Clay content: 15 to 27 percent fine granular; soft, very friable, slightly sticky, Content of rock fragments: 0 to 15 percent gravel slightly plastic; few medium and common very or channers fine and fine roots; many very fine and fine pores; Reaction: pH 6.6 to 7.3 neutral (pH 7.2); clear smooth boundary. Bw horizon Bw—7 to 12 inches; brown (10YR 5/3) loam, dark Hue: 10YR or 2.5Y brown (10YR 3/3) moist; moderate fine and Value: 4 to 7 dry; 3 to 6 moist medium subangular blocky structure; slightly Chroma: 2 to 4 hard, friable, slightly sticky, slightly plastic; few Texture (less than 2 mm): Loam, clay loam, sandy very fine and fine roots; common very fine clay loam, or fine sandy loam pores; very slightly effervescent; slightly alkaline Clay content: 18 to 35 percent (pH 7.4); abrupt smooth boundary. Content of rock fragments: 0 to 15 percent gravel Bk1—12 to 22 inches; light brownish gray (10YR 6/2) or channers loam, dark grayish brown (10YR 4/2) moist; weak Reaction: pH 6.6 to 8.4 fine and medium subangular blocky structure; moderately hard, friable, slightly sticky, slightly Bk horizons plastic; few very fine roots; common very fine Hue: 10YR or 2.5Y pores; common fine soft masses of lime; strongly Value: 5 to 8 dry; 4 to 6 moist effervescent; slightly alkaline (pH 7.8); clear Chroma: 2 to 4 smooth boundary. Texture (less than 2 mm): Loam, clay loam, fine Bk2—22 to 30 inches; light brownish gray (2.5Y 6/2) sandy loam, or silt loam loam, grayish brown (2.5Y 5/2) moist; weak fine Clay content: 18 to 35 percent and medium subangular blocky structure; Content of rock fragments: 0 to 15 percent gravel moderately hard, friable, slightly sticky, slightly or channers plastic; few very fine roots; common very fine Calcium carbonate equivalent: 5 to 10 percent pores; common fine and medium soft masses of Reaction: pH 7.4 to 8.4 lime; 5 percent channers; violently effervescent; BCk horizon moderately alkaline (pH 8.2); clear smooth Hue: 10YR or 2.5Y boundary. Value: 5 to 8 dry; 4 to 6 moist BCk—30 to 34 inches; light gray (2.5Y 7/2) loam, Chroma: 2 to 4 grayish brown (2.5Y 5/2) moist; weak fine and Texture (less than 2 mm): Loam, clay loam, fine medium subangular blocky structure; moderately sandy loam, or silt loam hard, friable, slightly sticky, slightly plastic; few Clay content: 18 to 35 percent very fine roots; common very fine pores; common Content of rock fragments: 5 to 35 percent gravel fine and medium soft masses of lime; 5 percent or channers soft siltstone chips; 10 percent channers; violently Calcium carbonate equivalent: 5 to 10 percent effervescent; moderately alkaline (pH 8.2); abrupt Reaction: pH 7.4 to 8.4 smooth boundary. Cr—34 to 60 inches; soft interbedded sandstone and siltstone bedrock; few very fine roots in cracks; Arrowpeak Series strongly effervescent. Depth class: Shallow (10 to 20 inches) Range in Characteristics Drainage class: Well drained Soil temperature: 42 to 47 degrees F Permeability: Moderately rapid (2 to 6 inches/hour) Moisture control section: Between 4 and 12 inches Landform: Mountain Thickness of the mollic epipedon: 7 to 15 inches Parent material: Residuum weathered from Depth to the Bk horizon: 10 to 20 inches sandstone or gabbro Depth to the Cr horizon: 20 to 40 inches Slope range: 2 to 60 percent Sweet Grass County Area, Montana—Part I 29

Elevation range: 5,500 to 7,500 feet Chroma: 2 or 3 Mean annual precipitation: 20 to 25 inches Texture (less than 2 mm): Loam or sandy loam Mean annual air temperature: 38 to 42 degrees F Clay content: 10 to 25 percent Frost-free period: 50 to 70 days Content of rock fragments: 50 to 80 percent—0 to 5 percent stones; 35 to 45 percent cobbles; Taxonomic Class: Loamy-skeletal, mixed, 15 to 30 percent gravel or channers superactive Lithic Haplocryolls Reaction: pH 6.1 to 7.3 Typical Pedon Arrowpeak very cobbly loam, in an area of Millerlake- Ashbon Series Arrowpeak-Adel complex, 8 to 35 percent slopes, in an area of rangeland, 800 feet south and 900 feet Depth class: Shallow (10 to 20 inches) west of the northeast corner of sec. 21, T. 2 N., Drainage class: Well drained R. 12 E.; USGS Raspberry Butte topographic Permeability: Moderately rapid (2 to 6 inches/hour) quadrangle (lat. 45o54'46" N.; long. 110o14'01" W.) Landform: Hill Parent material: Residuum weathered from tuff A—0 to 6 inches; brown (10YR 4/3) very cobbly loam, breccia very dark grayish brown (10YR 3/2) moist; weak Slope range: 8 to 60 percent medium subangular blocky structure parting to Elevation range: 3,900 to 6,200 feet strong fine granular; soft, very friable, slightly Mean annual precipitation: 15 to 20 inches sticky, slightly plastic; few medium, common fine, Mean annual air temperature: 40 to 45 degrees F and many very fine roots; common fine and many Frost-free period: 70 to 115 days very fine pores; 15 percent gravel; 25 percent cobbles; neutral (pH 6.6); clear smooth boundary. Bw—6 to 14 inches; brown (10YR 4/3) extremely Taxonomic Class: Loamy-skeletal, mixed, cobbly loam, dark brown (10YR 3/3) moist; weak superactive, nonacid, frigid Lithic Ustorthents medium subangular blocky structure; soft, very friable, slightly sticky, slightly plastic; common fine Typical Pedon and many very fine roots; common fine and medium and many very fine pores; 25 percent Ashbon very gravelly sandy loam, in an area of gravel; 35 percent cobbles; neutral (pH 6.6); Ashbon-Winkler-Rock outcrop complex, 35 to abrupt wavy boundary. 60 percent slopes, in an area of coniferous forest, R—14 inches; hard fractured igneous bedrock. 450 feet south and 250 feet west of the northeast corner of sec. 9, T. 2 S., R. 15 E.; USGS Packsaddle Range in Characteristics Butte topographic quadrangle (lat. 45o40'50" N.; Soil temperature: 40 to 44 degrees F long. 109o52'16" W.) Moisture control section: Between 8 inches and bedrock Oi—0 to 1 inch; slightly decomposed needles, twigs, Thickness of the mollic epipedon: 7 to 20 inches and leaves. Depth to bedrock: 10 to 20 inches A—1 to 6 inches; pale brown (10YR 6/3) very gravelly sandy loam, dark brown (10YR 4/3) moist; weak A horizon fine granular structure; soft, very friable, slightly Hue: 10YR sticky, slightly plastic; common very fine and Value: 3 or 4 dry; 2 or 3 moist fine roots; common very fine and fine pores; Chroma: 2 or 3 35 percent gravel; 3 percent cobbles; slightly Texture (less than 2 mm): Loam acid (pH 6.4); clear smooth boundary. Clay content: 18 to 27 percent C—6 to 16 inches; light brownish gray (10YR 6/2) Content of rock fragments: 35 to 60 percent—0 to very gravelly sandy loam, dark grayish brown 5 percent stones; 15 to 30 percent cobbles; (10YR 4/2) moist; massive; soft, very friable, 20 to 25 percent gravel or channers slightly sticky, slightly plastic; common fine and Reaction: pH 6.1 to 7.3 medium roots; common fine pores; 50 percent Bw horizon gravel; 5 percent cobbles; moderately acid Hue: 10YR (pH 6.0); abrupt smooth boundary. Value: 4 or 5 dry; 3 or 4 moist R—16 inches; volcanic mudflow breccia bedrock. 30 Soil Survey

Range in Characteristics fine subangular blocky structure parting to moderate fine granular; soft, very friable, slightly Soil temperature: 42 to 47 degrees F sticky, nonplastic; few fine and common very fine Moisture control section: Between 8 inches and the roots; common very fine and fine pores; slightly lithic contact alkaline (pH 7.6); abrupt smooth boundary. Depth to bedrock: 10 to 20 inches Bt—4 to 12 inches; dark grayish brown (10YR 4/2) A horizon clay loam, very dark grayish brown (10YR 3/2) Hue: 10YR or 2.5Y moist; weak fine and moderate very fine Value: 5 to 7 dry; 3 to 5 moist subangular blocky structure; very hard, friable, Chroma: 2 or 3 moderately sticky, moderately plastic; common Texture (less than 2 mm): Sandy loam very fine roots; common fine pores; common Clay content: 5 to 15 percent distinct discontinuous very dark brown (10YR Content of rock fragments: 15 to 60 percent—0 to 2/2), moist; clay films on faces of peds; slightly 5 percent cobbles; 15 to 55 percent gravel alkaline (pH 7.8); clear smooth boundary. Reaction: pH 6.1 to 7.3 Bk—12 to 21 inches; light brownish gray (2.5Y 6/2) loam, dark grayish brown (2.5Y 4/2) moist; C horizon moderate very fine prismatic structure parting to Hue: 10YR or 2.5Y weak fine and medium subangular blocky; Value: 5 to 7 dry; 4 or 5 moist; moderately hard, friable, slightly sticky, slightly Chroma: 2 or 3 plastic; few very fine roots; common fine pores; Texture (less than 2 mm): Sandy loam or loam disseminated lime; few fine and medium soft Clay content: 5 to 25 percent masses of lime; 5 percent gravel; strongly Content of rock fragments: 50 to 80 percent—0 to effervescent; moderately alkaline (pH 8.0); 15 percent cobbles; 50 to 65 percent gravel gradual smooth boundary. Reaction: pH 5.6 to 7.3 2BCk—21 to 60 inches; grayish brown (2.5Y 5/2) very gravelly loamy sand, dark grayish brown Attewan Series (2.5Y 4/2) moist; single grain; loose, nonsticky, nonplastic; few very fine roots; many medium Depth class: Very deep (greater than 60 inches) and coarse pores; common discontinuous Drainage class: Well drained carbonate coats on rock fragments; 40 percent Permeability: In the upper 0 to 21 inches = moderate gravel; 10 percent cobbles; strongly effervescent; (0.6 to 2.0 inches/hour); below this depth = rapid moderately alkaline (pH 8.0). (6 to 20 inches/hour) Range in Characteristics Landform: Stream terrace and terrace Parent material: Loamy over sandy and gravelly Soil temperature: 42 to 47 degrees F alluvium Moisture control section: Between 4 and 12 inches Slope range: 0 to 4 percent Thickness of the mollic epipedon: 7 to 12 inches Elevation range: 3,750 to 5,200 feet Depth to the Bk horizon: 10 to 21 inches Mean annual precipitation: 10 to 14 inches Depth to the 2BCk horizon: 20 to 40 inches Mean annual air temperature: 38 to 45 degrees F Note: Some pedons have a Bk2 horizon. Frost-free period: 95 to 125 days A horizon Taxonomic Class: Fine-loamy over sandy or sandy- Hue: 10YR or 2.5Y skeletal, mixed, superactive, frigid Aridic Value: 4 or 5 dry; 2 or 3 moist Argiustolls Chroma: 2 or 3 Texture (less than 2 mm): Loam Typical Pedon Clay content: 10 to 20 percent Attewan loam, in an area of Attewan loam, 0 to Content of rock fragments: 0 to 50 percent—0 to 4 percent slopes, in an area of rangeland, 2,150 feet 20 percent stones and cobbles; 0 to 30 percent north and 1,450 feet east of the southwest corner of gravel sec. 36, T. 1 N., R. 15 E.; USGS Greycliff topographic Reaction: pH 6.1 to 7.8 quadrangle (lat. 45o47'29" N.; long. 109o48'31" W.) Bt horizon A—0 to 4 inches; dark grayish brown (10YR 4/2) Hue: 10YR or 2.5Y loam, very dark brown (10YR 2/2) moist; weak Value: 4 to 6 dry; 3 or 4 moist Sweet Grass County Area, Montana—Part I 31

Chroma: 2 or 3 Typical Pedon Texture (less than 2 mm): Clay loam, sandy clay Bacbuster clay loam, in an area of Bacbuster- loam, or loam Castner complex, 2 to 8 percent slopes, in an area Clay content: 20 to 35 percent of rangeland, 400 feet north and 500 feet east of Content of rock fragments: 0 to 25 percent—0 to the southwest corner of sec. 28, T. 3 N., R. 13 E.; 5 percent stones and cobbles; 0 to 20 percent USGS Grosfield Ranch topographic quadrangle gravel (lat. 45o58'30" N.; long. 110o07'19" W.) Reaction: pH 6.6 to 7.8 A—0 to 5 inches; grayish brown (10YR 5/2) clay Bk horizon loam, very dark grayish brown (10YR 3/2) moist; Hue: 10YR or 2.5Y moderate fine and medium granular structure; Value: 5 to 8 dry; 4 to 6 moist slightly hard, friable, moderately sticky, Chroma: 2 to 4 moderately plastic; many very fine and fine roots; Texture (less than 2 mm): Loam, clay loam, sandy many very fine and fine pores; neutral (pH 7.2); clay loam, or sandy loam abrupt smooth boundary. Clay content: 15 to 30 percent Bt1—5 to 9 inches; brown (10YR 5/3) clay, dark Content of rock fragments: 0 to 30 percent—0 to brown (10YR 3/3) moist; strong fine and medium 5 percent stones and cobbles; 0 to 25 percent subangular blocky structure; moderately hard, gravel firm, very sticky, very plastic; common very fine Calcium carbonate equivalent: 5 to 15 percent and fine roots; common very fine and fine pores; Reaction: pH 7.4 to 8.4 continuous distinct dark brown (7.5YR 3/4) moist; 2BCk horizon clay films on faces of peds and lining pores; Hue: 10YR or 2.5Y slightly alkaline (pH 7.6); clear smooth boundary. Value: 4 to 7 dry; 4 or 5 moist Bt2—9 to 14 inches; yellowish brown (10YR 5/4) clay, Chroma: 2 to 4 brown (10YR 4/3) moist; strong coarse angular Texture (less than 2 mm): Loamy sand, sand, blocky structure parting to strong fine and loamy coarse sand, or coarse sand medium subangular blocky; very hard, firm, very Clay content: 0 to 10 percent sticky, very plastic; common very fine and fine Content of rock fragments: 35 to 75 percent—0 to roots; common very fine and fine pores; 15 percent stones and cobbles; 35 to 60 continuous distinct brown (7.5YR 4/4) moist; clay percent gravel films on faces of peds and lining pores; 5 percent Calcium carbonate equivalent: 5 to 15 percent gravel; slightly alkaline (pH 7.8); abrupt smooth Reaction: pH 7.4 to 8.4 boundary. Bk—14 to 27 inches; light brownish gray (10YR 6/2) gravelly clay loam, grayish brown (10YR 5/2) Bacbuster Series moist; moderate coarse prismatic structure; slightly hard, friable, moderately sticky, Depth class: Moderately deep (20 to 40 inches) moderately plastic; common very fine and fine Drainage class: Well drained roots; common very fine and fine pores; common Permeability: Slow (0.06 to 0.20 inch/hour) fine soft masses of lime; 20 percent soft shale Landform: Escarpment, hill, terrace, and swale on chips; 15 percent gravel; strongly effervescent; plain moderately alkaline (pH 8.4); clear smooth Parent material: Clayey residuum weathered from boundary. sandstone and shale Cr—27 to 60 inches; semiconsolidated calcareous Slope range: 2 to 35 percent shale; few carbonate coats on shale fragments. Elevation range: 4,200 to 6,200 feet Mean annual precipitation: 15 to 20 inches Range in Characteristics Mean annual air temperature: 38 to 45 degrees F Frost-free period: 70 to 115 days Soil temperature: 41 to 45 degrees F Moisture control section: Between 4 and 12 inches Taxonomic Class: Fine, mixed, superactive, frigid Thickness of the mollic epipedon: 7 to 15 inches Typic Argiustolls Depth to the Bk horizon: 11 to 24 inches 32 Soil Survey

Depth to the Cr horizon: 20 to 40 inches Permeability: In the upper 0 to 25 inches = moderate Note: Some pedons have a Btk horizon. (0.6 to 2.0 inches/hour); below this depth = rapid (6 to 20 inches/hour) A horizon Landform: Stream terrace Hue: 10YR Parent material: Sandy and gravelly alluvium Value: 4 or 5 dry; 2 or 3 moist Slope range: 0 to 8 percent Chroma: 2 or 3 Elevation range: 5,500 to 7,500 feet Texture (less than 2 mm): Clay loam Mean annual precipitation: 20 to 25 inches Clay content: 27 to 35 percent Mean annual air temperature: 36 to 45 degrees F Content of rock fragments: 0 to 25 percent—0 to Frost-free period: 50 to 70 days 15 percent cobbles; 0 to 10 percent gravel Reaction: pH 6.6 to 7.8 Taxonomic Class: Sandy-skeletal, mixed, Pachic Bt1 horizon Haplocryolls Hue: 10YR Value: 4 or 5 dry; 3 or 4 moist Bearmouth soils as mapped in this survey area are Chroma: 2 or 3 taxadjunct to the series. They are outside the series Texture (less than 2 mm): Clay, clay loam, or silty range with a mollic epipedon that is 16-inches or clay loam more thick and has a texture finer than loamy fine Clay content: 35 to 50 percent sand. Use and management are not significantly Content of rock fragments: 0 to 15 percent—0 to affected. Bearmouth series classifies Sandy-skeletal, 5 percent cobbles; 0 to 10 percent gravel; 0 to mixed Ustic Haplocryolls. 15 percent soft shale chips Reaction: pH 6.6 to 7.8 Typical Pedon Bt2 horizon Hue: 10YR or 7.5YR Bearmouth gravelly sandy loam, in an area of Value: 4 to 6 dry; 3 to 5 moist Bearmouth-Tiban-Beehive complex, 0 to 8 percent Chroma: 2 to 4 slopes, in an area of deciduous forest, 800 feet south Texture (less than 2 mm): Clay, clay loam, or silty and 2,300 feet east of the northwest corner of sec. clay loam 25, T. 3 S., R. 13 E.; USGS Squaw Peak topographic Clay content: 35 to 50 percent quadrangle (lat. 45o33'06" N.; long. 110o03'52" W.) Content of rock fragments: 0 to 15 percent—0 to 5 percent cobbles; 0 to 10 percent gravel; 0 to A—0 to 5 inches; very dark gray (10YR 3/1) gravelly 25 percent soft shale chips sandy loam, black (10YR 2/1) moist; weak very Reaction: pH 6.6 to 7.8 fine and fine granular structure; soft, very friable, nonsticky, nonplastic; common medium and many Bk horizon very fine and fine roots; many very fine and fine Hue: 2.5Y or 10YR pores; 15 percent gravel; 5 percent cobbles; Value: 5 to 7 dry; 4 or 5 moist neutral (pH 7.2); clear wavy boundary. Chroma: 2 to 4 Bw—5 to 25 inches; dark grayish brown (10YR 4/2) Texture (less than 2 mm): Clay loam or silty clay very gravelly sandy loam, very dark brown (10YR loam 2/2) moist; weak fine and medium subangular Clay content: 30 to 40 percent blocky structure; soft, very friable, nonsticky, Content of rock fragments: 0 to 25 percent—0 to nonplastic; common fine and medium and many 5 percent cobbles; 0 to 20 percent gravel; 0 to very fine roots; many very fine and fine pores; 60 percent soft shale chips 25 percent gravel; 10 percent cobbles; slightly Calcium carbonate equivalent: 2 to 15 percent alkaline (pH 7.4); clear wavy boundary. Reaction: pH 7.4 to 8.4 2C—25 to 60 inches; grayish brown (10YR 5/2) extremely gravelly loamy sand, dark grayish Bearmouth Taxadjunct brown (10YR 4/2) dry; single grain; loose, nonsticky, nonplastic; few very fine and fine roots; Depth class: Very deep (greater than 60 inches) 45 percent gravel; 20 percent cobbles; slightly Drainage class: Well drained effervescent; slightly alkaline (pH 7.8). Sweet Grass County Area, Montana—Part I 33

Range in Characteristics Taxonomic Class: Loamy-skeletal over sandy or sandy skeletal, mixed, superactive, frigid Aridic Soil temperature: 38 to 47 degrees F Argiustolls Moisture control section: Between 8 and 24 inches Typical Pedon Thickness of the mollic epipedon: 16 to 30 inches Depth to the 2C horizon: 16 to 25 inches Beaverell very gravelly loam, in an area of Attewan- Beaverell very gravelly loam, 0 to 4 percent slopes, A horizon 50 feet north and 1,000 feet east of the southwest Hue: 7.5YR or 10YR corner of sec. 27, T. 2 S., R. 23 E.; Stillwater County, Value: 3 to 5 dry; 2 or 3 moist Montana. Chroma: 1 to 3 Texture (less than 2 mm): Sandy loam or loam A—0 to 6 inches; grayish brown (10YR 5/2) very Clay content: 10 to 25 percent gravelly loam; very dark grayish brown (10YR Content of rock fragments: 10 to 80 percent—0 to 3/2) moist; massive, soft, very friable, nonsticky, 5 percent stones; 5 to 35 percent cobbles; 5 to nonplastic; common very fine and fine roots; 40 percent gravel 5 percent cobbles; 55 percent gravel; neutral Reaction: pH 6.6 to 7.3 (pH 7.2); gradual wavy boundary. Bt—6 to 12 inches; brown (10YR 4/3) extremely Bw horizon gravelly loam, very dark grayish brown (10YR Hue: 7.5YR or 10YR 3/2) moist; weak medium subangular blocky Value: 3 to 5 dry; 2 or 3 moist structure; slightly hard, friable, moderately sticky, Chroma: 2 or 3 moderately plastic; common faint clay films on Texture (less than 2 mm): Sandy loam faces of peds and rock fragments; 5 percent Clay content: 10 to 18 percent cobbles; 55 percent gravel; neutral (pH 7.2); Content of rock fragments: 35 to 60 percent—0 to gradual wavy boundary. 5 percent stones; 15 to 25 percent cobbles; 2Bk—12 to 60 inches; brown (10YR 5/3) very gravelly 20 to 30 percent gravel sand, dark brown (10YR 4/3) moist; single grain; Reaction: pH 6.6 to 7.8 loose, soft, very friable; 10 percent cobbles; 60 2C horizon percent gravel; common faint carbonate coats on Hue: 10YR or 2.5Y undersides of gravel; disseminated lime; strongly Value: 3 to 5 dry; 3 to 5 moist effervescent; moderately alkaline Chroma: 2 to 4 (pH 7.9). Texture (less than 2 mm): Loamy sand or sand Range in Characteristics Clay content: 0 to 10 percent Content of rock fragments: 60 to 90 percent—0 to Soil temperature: 40 to 47 degrees F 10 percent stones; 20 to 35 percent cobbles; Moisture control section: Between 4 and 12 inches 40 to 45 percent gravel Thickness of the mollic epipedon: 7 to 14 inches; may Reaction: pH 6.6 to 7.8 include all or part of the argillic horizon Depth to the 2Bk horizon: 10 to 20 inches Note: Some pedons have a 2C horizon. Beaverell Series A horizon Value: 2 or 3 moist Depth class: Very deep (greater than 60 inches) Chroma: 2 or 3 Drainage class: Well drained Texture (less than 2 mm): Loam or sandy clay Permeability: In the upper 0 to 12 inches = moderate loam (0.6 to 2.0 inches/hour); below this depth = rapid Clay content: 10 to 30 percent (6 to 20 inches/hour) Content of rock fragments: 5 to 70 percent—0 to Landform: Stream terrace and terrace 40 percent stones and cobbles; 5 to 40 percent Parent material: Gravelly alluvium gravel Slope range: 0 to 4 percent Reaction: pH 6.6 to 7.8 Elevation range: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Bt horizon Mean annual air temperature: 38 to 45 degrees F Hue: 10YR or 7.5YR Frost-free period: 95 to 125 days Value: 3 to 5 dry; 2 to 4 moist 34 Soil Survey

Chroma: 2 to 4 very fine and fine pores; 25 percent gravel; Texture (less than 2 mm): Clay loam, sandy clay 5 percent cobbles; slightly alkaline (pH 7.6); loam, or loam gradual smooth boundary. Clay content: 25 to 35 percent Bt1—5 to 11 inches; brown (10YR 4/3) very gravelly Content of rock fragments: 35 to 60 percent—0 to clay loam, dark brown (10YR 3/3) moist; weak 15 percent cobbles; 35 to 55 percent gravel fine prismatic structure parting to moderate fine Reaction: pH 6.6 to 7.8 subangular blocky; slightly hard, friable, slightly sticky, slightly plastic; common very fine and fine 2Bk horizon roots; many very fine to medium pores; distinct Hue: 10YR or 2.5Y discontinuous brown (7.5YR 4/4) moist; clay films Value: 4 to 8 dry; 4 to 6 moist on faces of peds and rock fragments; 30 percent Chroma: 2 to 4 gravel; 10 percent cobbles; neutral (7.2); gradual Texture (less than 2 mm): Loamy sand, sand, or wavy boundary. sandy loam Bt2—11 to 19 inches; brown (7.5YR 5/3) very gravelly Clay content: 0 to 10 percent loam, brown (7.5YR 4/3) moist; weak fine Content of rock fragments: 35 to 75 percent—5 to subangular blocky structure; slightly hard, very 40 percent stones and cobbles; 30 to friable, slightly sticky, slightly plastic; few fine and 60 percent gravel medium roots; faint patchy strong brown (7.5YR Calcium carbonate equivalent: 5 to 15 percent 4/6) moist; clay films on faces of peds and rock Reaction: pH 7.4 to 8.4 fragments; 40 percent gravel; 10 percent cobbles; neutral (7.2); clear smooth boundary. Beaverton Series 2Bk1—19 to 34 inches; yellowish brown (10YR 5/4) very gravelly loamy coarse sand, brown (10YR Depth class: Very deep (greater than 60 inches) 4/3) moist; single grain; loose, nonsticky, Drainage class: Well drained nonplastic; few fine and medium roots; few Permeability: In the upper 0 to 20 inches = moderate carbonate coats on undersides of rock fragments; (0.6 to 2.0 inches/hour); below this depth = rapid 45 percent gravel; 10 percent cobbles; 2 percent (6 to 20 inches/hour) stones; slightly effervescent; slightly alkaline Landform: Fan, stream terrace, and terrace (pH 7.6); clear smooth boundary. Parent material: Gravelly glaciofluvial deposits 2Bk2—34 to 60 inches; yellowish brown (10YR 5/4) Slope range: 0 to 4 percent extremely gravelly loamy coarse sand, dark Elevation range: 4,200 to 6,000 feet yellowish brown (10YR 4/4) moist; single Mean annual precipitation: 15 to 19 inches grain; loose, nonsticky, nonplastic; common Mean annual air temperature: 39 to 45 degrees F carbonate coats on undersides of rock fragments; Frost-free period: 85 to 115 days 50 percent gravel; 15 percent cobbles; 5 percent stones; strongly effervescent; moderately alkaline Taxonomic Class: Loamy-skeletal over sandy or (pH 8.2). sandy-skeletal, mixed, superactive, frigid Typic Range in Characteristics Argiustolls Soil temperature: 41 to 47 degrees F Typical Pedon Moisture control section: Between 4 and 12 inches Beaverton gravelly sandy clay loam, in an area of Thickness of the mollic epipedon: 7 to 14 inches Beaverton gravelly sandy clay loam, 0 to 4 percent Depth to the 2Bk horizon: 11 to 20 inches slopes, in an area of rangeland, 1,900 feet south and A horizon 1,400 feet west of the northeast corner of sec. 34, Hue: 7.5YR, 10YR, or 2.5Y T. 5 N., R. 13 E.; USGS Porcupine Butte topographic Value: 4 or 5 dry; 2 or 3 moist quadrangle (lat. 46o08'32" N.; long. 110o04'34" W.) Chroma: 2 or 3 A—0 to 5 inches; dark grayish brown (10YR 4/2) Texture (less than 2 mm): Sandy clay loam or gravelly sandy clay loam, very dark grayish brown loam (10YR 3/2) moist; weak fine subangular blocky Clay content: 10 to 30 percent structure parting to weak fine and medium Content of rock fragments: 5 to 60 percent—0 to granular; soft, very friable, slightly sticky, slightly 25 percent cobbles; 5 to 40 percent gravel plastic; common very fine and fine roots; many Reaction: pH 6.6 to 7.8 Sweet Grass County Area, Montana—Part I 35

Bt horizons Typical Pedon Hue: 7.5YR, 10YR, or 2.5Y Beehive gravelly sandy loam, in an area of Value: 4 or 5 dry; 3 or 4 moist Bearmouth-Tiban-Beehive complex, 0 to 8 percent Chroma: 2 or 3 slopes, in an area of deciduous forest, 1,350 feet Texture (less than 2 mm): Clay loam, sandy clay south and 2,000 feet west of the northeast corner loam, or loam of sec. 25, T. 3 S., R. 13 E.; USGS Squaw Peak Clay content: 25 to 35 percent topographic quadrangle (lat. 45o33'01" N.; long. Content of rock fragments: 35 to 60 percent—0 to 110o03'38" W.) 5 percent stones; 5 to 10 percent cobbles; 30 to 45 percent gravel Oi—0 to 2 inches; slightly decomposed leaves and Reaction: pH 6.6 to 7.8 twigs. A—2 to 10 inches; dark grayish brown (10YR 4/2) 2Bk1 horizon gravelly sandy loam, very dark grayish brown Hue: 7.5YR, 10YR, or 2.5Y (10YR 3/2) moist; weak very fine and fine Value: 5 to 7 dry; 4 to 6 moist; granular structure; soft, very friable, nonsticky, Chroma: 2 to 4 nonplastic; common very fine and fine roots; Texture (less than 2 mm): Loamy sand, loamy many very fine and fine pores; 20 percent gravel; coarse sand, or sand 10 percent cobbles; neutral (pH 7.2); clear Clay content: 0 to 10 percent smooth boundary. Content of rock fragments: 35 to 80 percent—0 to C1—10 to 26 inches; grayish brown (10YR 5/2) very 5 percent stones; 5 to 20 percent cobbles; gravelly loamy sand, dark grayish brown (10YR 30 to 55 percent gravel 4/2) moist; single grain; loose, nonsticky, Calcium carbonate equivalent: 5 to 15 percent nonplastic; few very fine and fine roots; Reaction: pH 7.4 to 8.4 35 percent gravel; 15 percent cobbles; slightly 2Bk2 horizon effervescent; slightly alkaline (pH 7.6); clear wavy Hue: 7.5YR, 10YR, or 2.5Y boundary. Value: 5 or 6 dry; 4 to 6 moist; C2—26 to 62 inches; light brownish gray (10YR 6/2) Chroma: 2 to 4 extremely cobbly sand, grayish brown (10YR 5/2) Texture (less than 2 mm): Loamy sand, loamy moist; single grain; loose, nonsticky, nonplastic; coarse sand, or sand few very fine roots; 35 percent gravel; 25 percent Clay content: 0 to 10 percent cobbles; 5 percent stones; slightly effervescent; Content of rock fragments: 35 to 80 percent—0 to slightly alkaline (pH 7.8). 5 percent stones; 5 to 20 percent cobbles; 30 to 55 percent gravel Range in Characteristics Calcium carbonate equivalent: 3 to 12 percent Soil temperature: 36 to 40 degrees F Reaction: pH 7.4 to 8.4 Moisture control section: Between 12 and 35 inches Depth to the seasonal high water table: 24 to Beehive Series 42 inches A horizon Depth class: Very deep (greater than 60 inches) Hue: 10YR or 2.5Y Drainage class: Somewhat poorly drained Value: 4 or 5 dry; 3 or 4 moist Permeability: Rapid (6 to 20 inches/hour) Chroma: 2 or 3 Landform: Flood plain Texture (less than 2 mm): Sandy loam Parent material: Sandy and gravelly alluvium Clay content: 10 to 20 percent Slope range: 0 to 8 percent Content of rock fragments: 15 to 35 percent—5 to Elevation range: 5,500 to 7,500 feet 10 percent cobbles; 10 to 25 percent gravel Mean annual precipitation: 20 to 25 inches Reaction: pH 6.1 to 7.8 Mean annual air temperature: 36 to 39 degrees F Frost-free period: 50 to 70 days C1 horizon Hue: 10YR or variegated Taxonomic Class: Sandy-skeletal, mixed Oxyaquic Value: 4 or 5 dry; 3 or 4 moist Cryofluvents Chroma: 2 to 4 36 Soil Survey

Texture (less than 2 mm): Loamy coarse sand, Typical Pedon loamy sand, or sandy loam Beenom gravelly loam, in an area of Whitlash- Clay content: 5 to 20 percent Beenom complex, 4 to 15 percent slopes, in an area Content of rock fragments: 40 to 70 percent— of rangeland, 1,300 feet south and 2,200 feet west of 10 to 20 percent cobbles; 30 to 50 percent the northeast corner of sec. 13, T. 1 N., R. 12 E.; gravel USGS Kelly Hills topographic quadrangle (lat. Reaction: pH 6.1 to 7.8 45o50'21" N.; long. 110o10'33" W.) C2 horizon A—0 to 6 inches; dark grayish brown (10YR 4/2) Hue: 10YR or variegated gravelly loam, very dark grayish brown (10YR Value: 4 to 6 dry; 3 to 5 moist 3/2) moist; moderate medium granular structure; Chroma: 2 to 4 soft, friable, slightly sticky, slightly plastic; many Texture (less than 2 mm): Loamy coarse sand, very fine to coarse roots; many very fine and fine loamy sand, sand, or coarse sand pores; 20 percent gravel; neutral (pH 6.6); clear Clay content: 0 to 10 percent smooth boundary. Content of rock fragments: 50 to 80 percent—0 to Bt1—6 to 13 inches; brown (10YR 4/3) clay loam, 5 percent stones; 25 to 35 percent cobbles; dark brown (10YR 3/3), moist; moderate fine and 20 to 40 percent gravel medium subangular blocky structure; slightly Reaction: pH 6.6 to 7.8 hard, friable, slightly sticky, slightly plastic; common very fine and fine roots; common very Beenom Taxadjunct fine and fine pores; distinct patchy dark yellowish brown (10YR 4/4) moist; clay films on faces of Depth class: Shallow (10 to 20 inches) peds; 10 percent gravel; neutral (pH 6.8); clear Drainage class: Well drained smooth boundary. Permeability: Moderate (0.6 to 2.0 inches/hour) Bt2—13 to 17 inches; yellowish brown (10YR 5/4) Landform: Escarpment, hill, structural bench, and gravelly clay loam, dark grayish brown (10YR 4/2) knoll on plain moist; moderate medium subangular blocky Parent material: Residuum weathered from structure; hard, friable, slightly sticky, slightly sandstone or andesite plastic; few very fine and fine roots; common Slope range: 2 to 15 percent fine pores; distinct discontinuous dark yellowish Elevation range: 4,200 to 6,200 feet brown (10YR 4/4) moist; clay films on faces Mean annual precipitation: 15 to 20 inches of peds and lining pores; 15 percent gravel; Mean annual air temperature: 38 to 45 degrees F 10 percent cobbles; neutral (pH 7.2); abrupt Frost-free period: 70 to 115 days smooth boundary. R—17 inches; hard sandstone. Taxonomic Class: Loamy, mixed, superactive, frigid Lithic Argiustolls Range in Characteristics

Beenom soils as mapped in this survey area are Soil temperature: 41 to 47 degrees F taxadjunct to the series. They are outside the Moisture control section: Between 4 and 12 inches series range with annual precipitation ranging up to Thickness of the mollic epipedon: 7 to 15 inches 20 inches. They are not dry in all parts of the 4- to Depth to bedrock: 10 to 20 inches 12-inch moisture control section for four-tenths or more of the cumulative days per year when the soil A horizon temperature at a depth of 20 inches below the soil Hue: 7.5YR, 10YR, or 2.5Y surface is higher than 5 degrees C in normal years. Value: 3 to 5 dry; 2 or 3 moist As mapped in map units 371D, 371E, 372D, 372E, Chroma: 2 or 3 394D, 395E, and 411E, the Beenom soils are outside Texture (less than 2 mm): Loam the series concept with andesite parent material. Use Clay content: 10 to 27 percent and management are not significantly affected. Content of rock fragments: 0 to 35 percent—0 to Beenom series classifies Loamy, mixed, superactive, 10 percent cobbles; 0 to 25 percent gravel frigid Aridic Lithic Argiustolls. Reaction: pH 6.6 to 7.8 Sweet Grass County Area, Montana—Part I 37

Bt1 horizon effervescent; slightly alkaline (pH 7.6); abrupt Hue: 7.5YR, 10YR, or 2.5Y smooth boundary. Value: 3 to 5 dry; 2 to 4 moist Bzg1—4 to 21 inches; gray (5Y 5/1) clay, dark gray Chroma: 2 or 3 (5Y 4/1) moist; common fine distinct strong brown Texture (less than 2 mm): Clay loam, loam, or (7.5YR 4/6) moist, redox concentrations; strong sandy clay loam fine and medium angular blocky structure; very Clay content: 18 to 35 percent hard, firm, very sticky, very plastic; many fine and Content of rock fragments: 0 to 15 percent gravel medium roots; common very fine and fine pores; Reaction: pH 7.4 to 8.4 common fine soft masses of salt; slightly effervescent; slightly alkaline (pH 7.8); clear Bt2 horizon smooth boundary. Hue: 7.5YR, 10YR, or 2.5Y Bzg2—21 to 31 inches; gray (5Y 6/1) clay, gray (5Y Value: 4 or 5 dry; 3 or 4 moist 5/1), moist; many fine and coarse prominent Chroma: 2 to 4 strong brown (7.5YR 4/6) moist, redox Texture (less than 2 mm): Clay loam, loam, or concentrations; strong fine and medium angular sandy clay loam blocky structure; very hard, firm, very sticky, very Clay content: 18 to 35 percent plastic; common fine and medium roots; common Content of rock fragments: 0 to 35 percent—0 to very fine and fine pores; common fine and 10 percent cobbles; 0 to 25 percent gravel medium soft masses of salt; slightly effervescent; Reaction: pH 7.4 to 8.4 moderately alkaline (pH 8.2); clear smooth boundary. Bigsag Family Bkzg1—31 to 48 inches; gray (5Y 6/1) clay, gray (5Y 5/1) moist; many medium and coarse prominent Depth class: Very deep (greater than 60 inches) strong brown (7.5YR 4/6) moist, redox Drainage class: Very poorly drained concentrations; strong medium and coarse Permeability: Very slow (less than 0.06 inch/hour) angular blocky structure; very hard, firm, very Landform: Flood plain, depression on flood plain, sticky, very plastic; common fine and medium pothole on landslide, swale on landslide, and roots; few very fine pores; few soft masses of depression on plain lime; many medium and coarse soft masses of Parent material: Clayey alluvium or colluvium salt; 10 percent gravel; strongly effervescent; weathered from sandstone and shale strongly alkaline (pH 8.6); gradual smooth Slope range: 0 to 4 percent boundary. Elevation range: 3,750 to 6,200 feet Bkzg2—48 to 60 inches; gray (5Y 6/1) gravelly clay, Mean annual precipitation: 10 to 20 inches gray (5Y 5/1) moist; many medium and coarse Mean annual air temperature: 39 to 46 degrees F prominent strong brown (7.5YR 4/6) moist, redox Frost-free period: 70 to 125 days concentrations; moderate medium and coarse angular blocky structure; very hard, firm, very Taxonomic Class: Fine, smectitic, calcareous, frigid sticky, very plastic; few soft masses of lime; Typic Halaquepts many medium and coarse soft masses of salt; 20 percent gravel; strongly effervescent; strongly Typical Pedon alkaline (pH 8.6). Bigsag clay, in an area of Work-Roy, bouldery-Bigsag Range in Characteristics family complex, 2 to 35 percent slopes, in an area of rangeland, 1,000 feet north and 2,100 feet east Soil temperature: 42 to 47 degrees F of the southwest corner of sec. 14, T. 3 S., R. 12 E.; Moisture control section: Between 4 to 12 inches USGS McLeod Basin topographic quadrangle (lat. Depth to the seasonal high water table: Ponded to 45o34'12" N.; long. 110o12'31" W.) 12 inches A—0 to 4 inches; grayish brown (2.5Y 5/2) clay, very A horizon dark grayish brown (2.5Y 3/2) moist; moderate Hue: 10YR or 2.5Y medium granular structure; very hard, friable, Value: 5 or 6 dry; 3 or 4 moist very sticky, very plastic; many very fine and fine Chroma: 1 or 2 roots; many very fine and fine pores; slightly Texture (less than 2 mm): Clay 38 Soil Survey

Clay content: 40 to 50 percent A—0 to 4 inches; brown (10YR 5/3) channery loam, Content of rock fragments: 0 to 15 percent gravel dark brown (10YR 4/3) moist; weak medium Electrical conductivity: 8 to 16 mmhos/cm granular structure; soft, very friable, slightly Sodium adsorption ratio: 4 to 13 sticky, slightly plastic; many very fine and fine Reaction: pH 6.6 to 7.8 roots; 20 percent hard shale and sandstone channers; slightly effervescent; moderately Bzg horizons alkaline (pH 7.9), clear smooth boundary. Hue: 2.5Y or 5Y Bw—4 to 14 inches; yellowish brown (10YR 5/4) very Value: 5 or 6 dry; 4 or 5 moist channery loam, dark brown (10YR 4/3) moist; Chroma: 1 or 2 weak medium prismatic structure parting to Redox concentrations: Few to many; chroma of 6 moderate fine subangular blocky; soft, very Texture (less than 2 mm): Clay or clay loam friable, slightly sticky, slightly plastic; many Clay content: 35 to 60 percent very fine roots; common very fine tubular pores; Content of rock fragments: 0 to 15 percent gravel 40 percent hard shale and sandstone channers; Electrical conductivity: 8 to 30 mmhos/cm slightly effervescent; moderately alkaline Sodium adsorption ratio: 4 to 13 (pH 8.4); clear smooth boundary. Reaction: pH 7.4 to 8.4 Bk1—14 to 24 inches; pale brown (10YR 6/3) very Bkzg horizons channery sandy loam, yellowish brown (10YR Hue: 2.5Y or 5Y 5/4) moist; massive; soft, very friable, slightly Value: 5 or 6 dry; 4 or 5 moist sticky, nonplastic; common very fine and fine Chroma: 1 or 2 roots matted around rock fragments; common or Redox concentrations: Few to many; chroma of 6 many carbonate coats on undersides of rock Texture (less than 2 mm): Clay or clay loam fragments; 50 percent hard shale and sandstone Clay content: 35 to 60 percent channers; violently effervescent; moderately Content of rock fragments: 0 to 25 percent gravel alkaline (pH 8.4); gradual wavy boundary. Electrical conductivity: 4 to 16 mmhos/cm Bk2—24 to 60 inches; pale brown (10YR 6/3) very Sodium adsorption ratio: 4 to 13 channery sandy loam, brown (10YR 5/3) moist; Calcium carbonate equivalent: 5 to 15 percent massive; soft, very friable, slightly sticky, Reaction: pH 7.9 to 9.0 nonplastic; few fine roots; common or many carbonate coats on undersides of rock fragments; 60 percent hard shale and sandstone channers; Birney Series moderately effervescent; moderately alkaline (pH 8.4). Depth class: Very deep (greater than 60 inches) Drainage class: Well drained Range in Characteristics Permeability: Moderate (0.6 to 2.0 inches/hour) Soil temperature: 42 to 47 degrees F Landform: Escarpment Moisture control section: Between 8 and 24 inches Parent material: Gravelly colluvium Depth to the Bk horizon: 10 to 15 inches Slope range: 15 to 60 percent Note: Some pedons have a C horizon. Elevation range: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches A horizon Mean annual air temperature: 43 to 46 degrees F Hue: 10YR Frost-free period: 95 to 125 days Value: 4 to 6 dry; 3 or 4 moist Chroma: 2 to 4 Taxonomic Class: Loamy-skeletal, mixed, Texture (less than 2 mm): Loam superactive, frigid Aridic Haplustepts Clay content: 10 to 25 percent Content of rock fragments: 0 to 35 percent Typical Pedon channers Calcium carbonate equivalent: 1 to 10 percent Birney channery loam, in area of Birney-Yawdim- Reaction: pH 7.4 to 8.4 Rock outcrop association, steep, 300 feet south and 500 feet west of the northeast corner of the southeast Bw horizon quarter of sec. 25, T. 2 S., R. 21 E.; Stillwater County, Hue: 10YR Montana. Value: 4 to 6 dry; 4 or 5 moist Sweet Grass County Area, Montana—Part I 39

Chroma: 2 to 4 or 6 weak medium prismatic structure parting to weak Texture (less than 2 mm): Loam or sandy loam fine subangular blocky; soft, very friable, Clay content: 10 to 25 percent nonsticky, nonplastic; common very fine and fine Content of rock fragments: 0 to 40 percent gravel roots; few fine and common very fine tubular or channers pores; few medium masses of lime; violently Calcium carbonate equivalent: 5 to 10 percent effervescent; moderately alkaline (pH 8.4); clear Reaction: pH 7.4 to 8.4 smooth boundary. Cr—16 to 60 inches; light gray (10YR 7/2) Bk horizons semiconsolidated sandstone; strongly Hue: 10YR effervescent; moderately alkaline (pH 8.2). Value: 5 or 6 dry; 4 or 5 moist Chroma: 2 to 4 or 6 Range in Characteristics Texture (less than 2 mm): Loam, sandy loam, or Soil temperature: 43 to 47 degrees F fine sandy loam Moisture control section: Between 8 inches and the Clay content: 10 to 25 percent paralithic contact Content of rock fragments: 35 to 80 percent—0 to Depth to the Cr horizon: 10 to 20 inches 20 percent flagstones; 35 to 60 percent gravel or channers A horizon Calcium carbonate equivalent: 5 to 15 percent Hue: 2.5Y or 10YR Reaction: pH 7.9 to 8.4 Value: 5 to 7 dry; 4 or 5 moist Chroma: 2 or 3 Texture (less than 2 mm): Fine sandy loam Blacksheep Series Clay content: 5 to 15 percent Content of rock fragments: 0 to 35 percent—0 to Depth class: Shallow (10 to 20 inches) 15 percent cobbles; 0 to 20 percent gravel Drainage class: Well drained Reaction: pH 7.4 to 8.4 Permeability: Moderately rapid (2 to 6 inches/hour) Bk horizon Landform: Escarpment, hill, and knoll on plain Hue: 2.5Y, 7.5YR, or 10YR Parent material: Sandy residuum weathered from Value: 5 to 7 dry; 5 or 6 moist calcareous sandstone Chroma: 2 to 4 Slope range: 2 to 25 percent Texture (less than 2 mm): Fine sandy loam, very Elevation range: 3,750 to 5,200 feet fine sandy loam, or sandy loam Mean annual precipitation: 10 to 14 inches Clay content: 5 to 15 percent Mean annual air temperature: 43 to 46 degrees F Content of rock fragments: 0 to 35 percent—0 to Frost-free period: 95 to 125 days 15 percent cobbles; 0 to 20 percent gravel Calcium carbonate equivalent: 5 to 10 percent Taxonomic Class: Loamy, mixed, superactive, Reaction: pH 7.9 to 8.4 calcareous, frigid, shallow Aridic Ustorthents

Typical Pedon Blossberg Taxadjunct Blacksheep fine sandy loam, in an area of Depth class: Very deep (greater than 60 inches) Busby-Blacksheep-Twilight fine sandy loams, 8 to Drainage class: Poorly drained 25 percent slopes, 500 feet north and 1,200 feet east Permeability: In the upper 0 to 26 inches = moderate of the southwest corner of sec. 32, T. 2 N., R. 46 E.; (0.6 to 2.0 inches/hour); below this depth = rapid Custer County, Montana. (6 to 20 inches/hour) A—0 to 6 inches; brown (10YR 5/3) fine sandy loam, Landform: Stream terrace dark brown (10YR 4/3) moist; weak medium Parent material: Loamy over sandy and gravelly granular structure; soft, very friable, nonsticky, alluvium nonplastic; common very fine and fine roots; Slope range: 0 to 4 percent common very fine tubular pores; slightly alkaline Elevation range: 3,750 to 4,300 feet (pH 7.4); clear smooth boundary. Mean annual precipitation: 10 to 14 inches Bk—6 to 16 inches; light gray (2.5Y 7/2) very fine Mean annual air temperature: 37 to 45 degrees F sandy loam, grayish brown (2.5Y 5/2) moist; Frost-free period: 115 to 125 days 40 Soil Survey

Taxonomic Class: Fine-loamy over sandy or sandy- (7.5YR 5/8) iron concentrations; 3 percent skeletal, mixed, superactive, frigid Typic cobbles; 4 percent gravel; slightly alkaline Argiaquolls (pH 7.7); clear smooth boundary. BC—19 to 26 inches; brown (10YR 5/3) gravelly The Blossberg soils as mapped in map unit 296B sandy loam, dark yellowish brown (10YR 4/4) are a taxadjunct to the series. They are outside moist; weak fine subangular blocky structure; the series range with an argillic horizon; irrigation- slightly hard, firm, slightly sticky, slightly plastic; induced episaturation; the profile is not gleyed below common medium and many very fine and fine the Btg horizon in the Bt, BC, and 2C horizons; and roots; many fine and medium pores; common these soils have greater than 15 percent rock medium distinct strong brown (7.5YR 5/8) iron fragments in the A horizon and on the surface. concentrations; 20 percent gravel; 5 percent Blossberg series classifies as Fine-loamy over sandy cobbles; moderately alkaline (pH 8.1); abrupt or sandy-skeletal, mixed, superactive, frigid Typic smooth boundary. Endoaquolls. 2C1—26 to 49 inches; pale brown (10YR 6/3) extremely cobbly coarse sand, yellowish brown Typical Pedon (10YR 5/4) moist; single grain; loose, nonsticky, Blossberg cobbly loam, in an area of Blossberg nonplastic; common fine and medium roots; cobbly loam, 0 to 4 percent slopes, in an area of strongly effervescent; 40 percent gravel; rangeland, 400 feet north and 2,200 feet east of the 25 percent cobbles; 5 percent stones; moderately southwest corner of sec. 26, T. 1 N., R. 14 E.; USGS alkaline (pH 8.2); gradual smooth boundary. Big Timber topographic quadrangle (lat. 45o48'03" N.; 2C2—49 to 60 inches; pale brown (10YR 6/3) long. 109o57'01" W.) extremely gravelly coarse sand, yellowish brown (10YR 5/4) moist; single grain; loose, nonsticky, Oi—0 to 2 inches; partially decomposed organic nonplastic; common fine and medium roots; matter. strongly effervescent; 55 percent gravel; A—2 to 8 inches; dark gray (10YR 4/1) cobbly loam, 15 percent cobbles; moderately alkaline (pH 8.2). very dark brown (10YR 2/2) moist; weak fine and medium granular structure; slightly hard, friable, Range in Characteristics: slightly sticky, slightly plastic; many very fine to medium roots; common fine and medium pores; Soil temperature: 39 to 47 degrees F common medium prominent reddish yellow Moisture control section: Between 4 and 12 inches (7.5YR 6/8) iron concentrations; 18 percent Thickness of the mollic epipedon: 11 to 14 inches cobbles; 3 percent gravel; slightly alkaline Depth to the Bt horizon: 6 inches (pH 7.5); abrupt smooth boundary. Depth to the 2C horizon: 22 to 24 inches Btg—8 to 13 inches; brown (7.5YR 5/2) sandy clay Depth to seasonal high water table: 0 to 12 inches loam, brown (7.5YR 4/2) moist; weak medium from June to August subangular blocky structure; slightly hard, firm, A horizon moderately sticky, moderately plastic; common Hue: 10YR medium and many very fine and fine roots; many Value: 4 dry; 2 or 3 moist fine and medium pores; few prominent dark Chroma: 1 dry; 2 or 3 moist brown (7.5YR 3/2) and brown (7.5YR 4/2) clay Texture (less than 2 mm): Loam or clay loam films on faces of peds and in pores; many Clay content: 20 to 30 percent medium prominent strong brown (7.5YR 5/8) iron Content of rock fragments: 18 to 30 percent— concentrations; 5 percent cobbles; 5 percent 15 to 20 percent cobbles; 3 to 10 percent gravel; slightly alkaline (pH 7.4); clear smooth gravel boundary. Reaction: pH 7.4 to 7.8 Bt—13 to 19 inches; brown (7.5YR 5/4) sandy clay loam, brown (7.5YR 4/4) moist; weak medium Btg horizon subangular blocky structure; hard, firm, Hue: 10YR or 7.5YR moderately sticky, moderately plastic; common Value: 5 dry; 4 moist medium and many very fine and fine roots; many Chroma: 2 fine and medium pores; few prominent brown Texture (less than 2 mm): Sandy clay loam or clay (7.5YR 4/2) clay films on faces of peds and in loam pores; many medium prominent strong brown Clay content: 30 to 35 percent Sweet Grass County Area, Montana—Part I 41

Content of rock fragments: 5 to 15 percent—0 to Typical Pedon 5 percent cobbles; 5 to 10 percent gravel Bonebasin loam, in an area of Bowery-Nesda- Reaction: pH 7.4 to 7.8 Bonebasin complex, 2 to 15 percent slopes, in an area of rangeland, 2,300 feet south and 400 feet Bt horizon east of the northwest corner of sec. 26, T. 2 S., Hue: 10YR or 7.5YR R. 13 E.; USGS McLeod topographic quadrangle Value: 5 dry; 4 moist (lat. 45o38'03" N.; long. 110o05'37" W.) Chroma: 4 Texture (less than 2 mm): Sandy clay loam, clay Oi—0 to 1 inch; partially decomposed organic matter. loam, or sandy clay A—1 to 4 inches; dark gray (10YR 4/1) loam, black Clay content: 30 to 37 percent (10YR 2/1) moist; few fine and medium faint dark Content of rock fragments: 5 to 15 percent—0 to yellowish brown (10YR 5/6) moist, redox 5 percent cobbles; 5 to 10 percent gravel concentrations; moderate very fine and fine Reaction: pH 7.4 to 7.8 granular structure; soft, friable, nonsticky, nonplastic; many very fine to medium roots; BC horizon common very fine and fine pores; 5 percent Hue: 10YR gravel; slightly alkaline (pH 7.6); clear wavy Value: 5 dry; 4 or 5 moist boundary. Chroma: 3 dry; 2 to 4 moist Ag—4 to 15 inches; grayish brown (10YR 5/2) loam, Texture (less than 2 mm): Sandy loam or loam very dark grayish brown (10YR 3/2) moist; Clay content: 13 to 20 percent common fine and medium distinct yellowish Content of rock fragments: 10 to 25 percent—0 to brown (10YR 5/6) moist, redox concentrations; 5 percent cobbles; 10 to 20 percent gravel weak medium subangular blocky structure Reaction: pH 7.4 to 8.2 parting to moderate fine granular; soft, friable, 2C horizons nonsticky, nonplastic; common very fine and fine Hue: 10YR roots; common very fine and fine pores; 5 percent Value: 6 dry; 5 or 6 moist gravel; neutral (pH 7.0); abrupt smooth boundary. Chroma: 3 dry; 2 to 4 moist Cg—15 to 23 inches; gray (2.5Y 6/1) gravelly sandy Texture (less than 2 mm): Coarse sand loam, very dark gray (2.5Y 4/1) moist; common Clay content: 2 to 5 percent fine and medium distinct light olive brown (2.5Y Content of rock fragments: 45 to 80 percent—5 to 5/6) moist, redox concentrations; few faint very 25 percent stones and cobbles; 40 to dark gray (5Y 3/1) moist, redox depletions; weak 55 percent gravel medium subangular blocky structure; soft, very Reaction: pH 7.9 to 8.4 friable, nonsticky, nonplastic; few very fine and fine roots; common very fine and fine pores; thin strata of loam; 25 percent gravel; neutral (pH 7.0); Bonebasin Series clear wavy boundary. 2C—23 to 61 inches; gray (2.5Y 5/1) extremely Depth class: Very deep (greater than 60 inches) gravelly loamy sand, dark gray (2.5Y 4/1) moist; Drainage class: Very poorly drained few fine and medium distinct light olive brown Permeability: In the upper 0 to 21 inches = (2.5Y 5/6) moist, redox concentrations; single moderately slow (0.2 to 0.6 inch/hour); below this grain; loose, nonsticky, nonplastic; 10 percent depth = rapid (6 to 20 inches/hour) cobbles; 50 percent gravel; neutral (pH 7.0). Landform: Flood plain Range in Characteristics Parent material: Gravelly alluvium Slope range: 2 to 4 percent Soil temperature: 40 to 46 degrees F Elevation range: 5,300 to 6,200 feet Moisture control section: Between 4 and 12 inches Mean annual precipitation: 17 to 20 inches Thickness of the mollic epipedon: 10 to 24 inches Mean annual air temperature: 39 to 42 degrees F Depth to the seasonal high water table: 0 to Frost-free period: 70 to 90 days 12 inches Depth to the 2C horizon: 20 to 40 inches Taxonomic Class: Fine-loamy over sandy or sandy- A horizons skeletal, mixed, superactive, frigid Fluvaquentic Hue: 10YR, 2.5Y, or 5Y Endoaquolls Value: 4 or 5 dry; 2 or 3 moist 42 Soil Survey

Chroma: 1 or 2 Typical Pedon Redox concentrations: Few to many Bowery loam, in an area of Bowery loam, 2 to Redox depletions: None to common 8 percent slopes, in an area of rangeland, 1,250 feet Texture (less than 2 mm): Loam south and 800 feet east of the northwest corner of Clay content: 18 to 27 percent sec. 24, T. 4 N., R. 6 E.; Gallatin County, Montana. Content of rock fragments: 0 to 5 percent gravel Calcium carbonate equivalent: 0 to 15 percent A1—0 to 9 inches; dark grayish brown (10YR 4/2) Reaction: pH 6.6 to 7.8 loam, very dark brown (10YR 2/2) moist; weak medium subangular blocky structure parting to Cg horizon moderate very fine and fine subangular blocky; Hue: 10YR, 2.5Y, or 5Y slightly hard, friable, slightly sticky, slightly plastic; Value: 4 to 6 dry; 3 to 5 moist many very fine and fine roots; common very fine Chroma: 1 or 2 and fine pores; 5 percent gravel; slightly acid; Redox concentrations: Few to common clear smooth boundary. Redox depletions: None to common A2—9 to 22 inches; dark gray (10YR 4/1) loam; very Texture (less than 2 mm): Sandy loam, loam, silt dark brown (10YR 2/2) moist; moderate very fine loam, or silty clay loam with strata of finer and subangular blocky structure parting to weak very coarser textured material fine and moderate fine granular; slightly hard, Clay content: 18 to 35 percent friable, slightly sticky, slightly plastic; common Content of rock fragments: 5 to 25 percent gravel very fine and fine roots; common very fine and Calcium carbonate equivalent: 0 to 15 percent fine pores; 5 percent gravel; neutral; gradual Reaction: pH 6.6 to 8.4 smooth boundary. 2C horizon Bw1—22 to 36 inches; dark grayish brown (10YR 4/2) Hue: 10YR, 2.5Y, or 5Y clay loam, very dark brown (10YR 2/2) moist; Value: 4 to 6 dry; 3 to 5 moist weak very fine and fine subangular blocky Chroma: 1 or 2 structure parting to weak fine granular; slightly Redox concentrations: None to common hard, friable, slightly sticky, slightly plastic; few Redox depletions: None to common very fine and fine roots; common very fine and Texture (less than 2 mm): Loamy sand, loamy fine pores; 10 percent gravel; neutral; gradual coarse sand, or sand smooth boundary. Clay content: 0 to 10 percent Bw2—36 to 60 inches; grayish brown (10YR 5/2) clay Content of rock fragments: 35 to 70 percent— loam, very dark grayish brown (10YR 3/2) moist; 10 to 20 percent cobbles; 25 to 50 percent weak medium prismatic structure parting to weak gravel fine and medium subangular blocky; slightly hard, Reaction: pH 6.6 to 7.8 firm, moderately sticky, moderately plastic; few fine roots; few very fine pores; 10 percent gravel; neutral. Bowery Series Range in Characteristics Depth class: Very deep (greater than 60 inches) Soil temperature: 41 to 45 degrees F Drainage class: Well drained Moisture control section: Between 4 and 12 inches Permeability: Moderate (0.6 to 2.0 inches/hour) Thickness of the mollic epipedon: 16 to 60 inches Landform: Escarpment, fan, landslide, stream terrace, A horizons fan on escarpment, swale on fan, swale on hill, Hue: 10YR or 2.5Y swale on moraine, and fan on mountain Value: 3 or 4 dry; 2 or 3 moist Parent material: Loamy alluvium or colluvium Chroma: 1 to 3 Slope range: 0 to 45 percent Texture (less than 2 mm): Loam or clay loam Elevation range: 4,200 to 6,200 feet Clay content: 18 to 35 percent Mean annual precipitation: 15 to 20 inches Content of rock fragments: 0 to 15 percent gravel Mean annual air temperature: 39 to 45 degrees Reaction: pH 6.1 to 7.3 Frost-free period: 70 to 115 days Bw1 horizon Taxonomic Class: Fine-loamy, mixed, superactive, Hue: 10YR or 2.5Y frigid Pachic Haplustolls Value: 4 or 5 dry; 2 to 4 moist Sweet Grass County Area, Montana—Part I 43

Chroma: 2 to 4 effervescent; slightly alkaline (pH 7.8); clear Texture (less than 2 mm): Loam or clay loam smooth boundary. Clay content: 18 to 35 percent Bk1—13 to 17 inches; light brownish gray (10YR 6/2) Content of rock fragments: 10 to 25 percent—0 to loam, grayish brown (10YR 5/2) moist; weak 5 percent cobbles; 10 to 20 percent gravel medium prismatic structure; soft, very friable, Reaction: pH 6.1 to 7.3 slightly sticky, slightly plastic; few fine and medium roots; many fine pores; common fine and Bw2 horizon medium soft masses of lime; violently Hue: 10YR or 2.5Y effervescent; moderately alkaline (pH 8.4); Value: 4 or 5 dry; 3 or 4 moist gradual smooth boundary. Chroma: 2 to 4 Bk2—17 to 28 inches; light gray (10YR 7/2) silt loam, Texture (less than 2 mm): Loam or fine sandy light brownish gray (10YR 6/2) moist; weak loam coarse prismatic structure; soft, friable, slightly Clay content: 10 to 27 percent sticky, slightly plastic; many very fine pores; Content of rock fragments: 10 to 25 percent—0 to common fine and medium soft masses of lime; 5 percent cobbles; 10 to 20 percent gravel 10 percent gravel; violently effervescent; Reaction: pH 6.1 to 7.3 moderately alkaline (pH 8.4); gradual smooth boundary. Boxwell Series Cr—28 to 60 inches; light gray (2.5Y 7/2) weakly consolidated interbedded siltstone and Depth class: Moderately deep (20 to 40 inches) sandstone; strongly effervescent. Drainage class: Well drained Range in Characteristics Permeability: Moderate (0.6 to 2.0 inches/hour) Landform: Swale on plain Soil temperature: 41 to 47 degrees F Parent material: Loamy residuum weathered from Moisture control section: Between 4 and 12 inches sandstone and siltstone Thickness of the mollic epipedon: 5 to 12 inches; the Slope range: 2 to 15 percent upper 7 inches, when mixed, meet the color Elevation range: 3,750 to 5,200 feet requirements of a mollic epipedon. Mean annual precipitation: 10 to 14 inches Depth to the Bk horizon: 8 to 16 inches Mean annual air temperature: 39 to 45 degrees F Depth to the Cr horizon: 20 to 40 inches Frost-free period: 95 to 125 days A horizon Hue: 10YR or 2.5Y Taxonomic Class: Fine-loamy, mixed, superactive, Value: 5 dry; 2 or 3 moist frigid Aridic Haplustolls Chroma: 2 or 3 Typical Pedon Texture (less than 2 mm): Loam Clay content: 15 to 27 percent Boxwell loam, in an area of Cabbart-Boxwell loams, Content of rock fragments: 0 to 15 percent gravel 2 to 8 percent slopes, in an area of cropland, 950 feet or channers south and 200 feet west of the northeast corner of Reaction: pH 6.1 to 7.8 sec. 9, T. 3 N., R. 17 E.; USGS Gibson topographic quadrangle (lat. 46o01'47" N.; long. 109o36'41" W.) Bw horizon Hue: 10YR or 2.5Y Ap—0 to 7 inches; grayish brown (10YR 5/2) loam, Value: 5 to 7 dry; 3 to 5 moist; very dark grayish brown (10YR 3/2) moist; weak Chroma: 2 to 4 medium granular structure; slightly hard, very Texture (less than 2 mm): Loam, clay loam, silt friable, slightly sticky, slightly plastic; many very loam, or silty clay loam fine and fine roots; many very fine pores; slightly Clay content: 18 to 35 percent alkaline (pH 7.8); abrupt smooth boundary. Content of rock fragments: 0 to 15 percent gravel Bw—7 to 13 inches; light brownish gray (10YR 6/2) or channers loam, dark grayish brown (10YR 4/2) moist; weak Reaction: pH 6.6 to 7.8 medium and coarse subangular blocky structure; slightly hard, friable, slightly sticky, slightly plastic; Bk horizons few medium and coarse and many very fine and Hue: 10YR, 2.5Y, or 5Y fine roots; many very fine pores; strongly Value: 6 to 8 dry; 4 to 7 moist 44 Soil Survey

Chroma: 2 or 3 Bw—19 to 30 inches; grayish brown (10YR 5/2) Texture (less than 2 mm): Loam, clay loam, silt sandy loam, very dark grayish brown (10YR 3/2) loam, or silty clay loam moist; weak coarse prismatic structure; soft, very Clay content: 15 to 30 percent friable, nonsticky, nonplastic; common very fine Content of rock fragments: 0 to 15 percent gravel and fine roots; many very fine and fine pores; or channers 10 percent gravel; neutral (pH 7.0); gradual Calcium carbonate equivalent: 15 to 30 percent smooth boundary. Reaction: pH 7.4 to 8.4 BC—30 to 60 inches; brown (10YR 5/3) sandy loam, brown (10YR 4/3) moist; massive; soft, very friable, nonsticky, nonplastic; few very fine and Breeton Series fine roots; many very fine and fine pores; 10 percent gravel; neutral (pH 7.0). Depth class: Very deep (greater than 60 inches) Drainage class: Well drained Range in Characteristics Permeability: Moderately rapid (2 to 6 inches/hour) Landform: Fan, hill, and stream terrace Soil temperature: 38 to 45 degrees F Parent material: Coarse-loamy alluvium Moisture control section: Between 8 and 24 inches Slope range: 2 to 15 percent Thickness of the mollic epipedon: 16 to 40 inches Elevation range: 4,200 to 6,200 feet Mean annual precipitation: 15 to 20 inches A horizons Mean annual air temperature: 43 to 46 degrees F Hue: 10YR or 2.5Y Frost-free period: 70 to 115 days Value: 3 or 4 dry; 2 or 3 moist Chroma: 1 or 2 Taxonomic Class: Coarse-loamy, mixed, Texture (less than 2 mm): Sandy loam or loam superactive, frigid Pachic Haplustolls Clay content: 8 to 25 percent Content of rock fragments: 0 to 15 percent gravel Typical Pedon Reaction: pH 6.1 to 7.3 Breeton sandy loam, in an area of Breeton sandy Bw horizon loam, 8 to 15 percent slopes, in an area of pasture, Hue: 10YR or 2.5Y 1,400 feet south and 550 feet west of the northeast Value: 4 to 6 dry; 3 to 5 moist corner of sec. 8, T. 2 S., R. 15 E.; USGS Ross Canyon Chroma: 2 or 3 topographic quadrangle (lat. 45o40'40" N.; long. Texture (less than 2 mm): Sandy loam, coarse 109o53'37" W.) sandy loam, or loam Ap—0 to 5 inches; dark grayish brown (10YR 4/2) Clay content: 8 to 18 percent sandy loam, very dark grayish brown (10YR 3/2) Content of rock fragments: 5 to 30 percent gravel moist; weak fine granular structure; soft, very Reaction: pH 6.1 to 7.8 friable, nonsticky, nonplastic; many very fine and BC horizon fine roots; many very fine and fine pores; slightly Hue: 10YR or 2.5Y acid (pH 6.4) clear smooth boundary. Value: 5 or 6 dry; 4 or 5 moist A2—5 to 13 inches; dark grayish brown (10YR 4/2) Chroma: 2 or 3 sandy loam, very dark grayish brown (10YR 3/2) Texture (less than 2 mm): Sandy loam, coarse moist; weak fine and medium subangular blocky sandy loam, or loamy fine sand structure; soft, very friable, nonsticky, nonplastic; Clay content: 5 to 15 percent common very fine and fine roots; many very fine Content of rock fragments: 10 to 30 percent and fine pores; neutral (pH 6.6); clear smooth gravel boundary. Reaction: pH 6.1 to 7.8 A3—13 to 19 inches; dark grayish brown (10YR 4/2) sandy loam, very dark grayish brown (10YR 3/2) moist; weak medium and coarse subangular Bridger Series blocky structure; soft, very friable, nonsticky, nonplastic; common very fine and fine roots; Depth class: Very deep (greater than 60 inches) many very fine and fine pores; 5 percent gravel; Drainage class: Well drained neutral (pH 6.8); clear smooth boundary. Permeability: Moderately slow (0.2 to 0.6 inch/hour) Sweet Grass County Area, Montana—Part I 45

Landform: Fan, landslide, moraine, mountain, terrace, gravel; 5 percent cobbles; neutral (pH 7.2); clear and fan on mountain smooth boundary. Parent material: Silty and clayey alluvium or till Btk—27 to 34 inches; grayish brown (2.5Y 5/2) clay Slope range: 2 to 45 percent loam, dark grayish brown (2.5Y 4/2) moist; strong Elevation range: 5,500 to 7,500 feet fine and medium subangular blocky structure; Mean annual precipitation: 20 to 25 inches very hard, firm, moderately sticky, moderately Mean annual air temperature: 36 to 38 degrees F plastic; few very fine and fine roots; few very fine Frost-free period: 50 to 70 days pores; few distinct patchy dark yellowish brown (2.5Y 4/2) moist; clay films on faces of peds; Taxonomic Class: Fine, mixed, superactive Ustic many fine and medium irregular masses of lime; Argicryolls 10 percent gravel; 2 percent subangular cobbles; strongly effervescent; slightly alkaline (pH 7.8); Typical Pedon clear smooth boundary. Bridger cobbly clay loam, in an area of Tibson, Bk—34 to 60 inches; light brownish gray (2.5Y 6/2) extremely bouldery-Bridger, extremely bouldery- gravelly clay loam, grayish brown (2.5Y 5/2) Adel complex, 8 to 35 percent slopes, in an area moist; strong fine and medium angular blocky of rangeland, 2,200 feet north and 800 feet east structure; very hard, firm, moderately sticky, of the southwest corner of sec. 2, T. 3 S., R. 12 E.; moderately plastic; few very fine pores; many USGS McLeod Basin topographic quadrangle fine irregular masses of lime; 10 percent gravel; (lat. 45o36'08" N.; long. 110o12'50" W.) 5 percent cobbles; violently effervescent; slightly alkaline (pH 7.8). A—0 to 8 inches; dark gray (10YR 4/1) cobbly clay loam, very dark gray (10YR 3/1) moist; moderate Range in Characteristics very fine and fine granular structure; soft, very Soil temperature: 36 to 47 degrees F friable, slightly sticky, slightly plastic; common Moisture control section: Between 4 and 12 inches very fine to medium roots; many very fine and Thickness of the mollic epipedon: 7 to 16 inches fine pores; 10 percent gravel; 10 percent cobbles; Depth to the Bk horizon: 17 to 40 inches slightly acid (pH 6.4); clear smooth boundary. Note: Some pedons do not have a Btk horizon. Bt1—8 to 12 inches; light brownish gray (10YR 6/2) clay loam, dark grayish brown (10YR 4/2) moist; A horizon strong very fine and fine subangular blocky Hue: 7.5YR, 10YR, or 2.5Y structure; moderately hard, firm, moderately Value: 3 to 5 dry; 2 or 3 moist sticky, moderately plastic; common very fine to Chroma: 1 or 2 medium roots; common very fine and fine pores; Texture (less than 2 mm): Clay loam or loam common distinct discontinuous dark grayish Clay content: 18 to 35 percent brown (10YR 4/2) moist; clay films on faces of Content of rock fragments: 5 to 35 percent—0 to peds; 5 percent gravel; 5 percent cobbles; slightly 10 percent stones and cobbles; 5 to 25 percent acid (pH 6.2); clear smooth boundary. gravel Bt2—12 to 19 inches; dark grayish brown (2.5Y 5/2) Reaction: pH 6.1 to 7.3 clay, very dark grayish brown (2.5Y 4/2) moist; Bt horizons strong medium prismatic structure parting to Hue: 7.5YR, 10YR, or 2.5Y strong medium subangular blocky; very hard, Value: 5 or 6 dry; 3 to 5 moist very firm, very sticky, very plastic; common very Chroma: 2 to 4 fine to medium roots; few very fine and fine pores; Texture (less than 2 mm): Clay, clay loam, or silty many prominent continuous dark yellowish brown clay (2.5Y 4/2) moist; clay films on faces of peds; Clay content: 35 to 50 percent 5 percent gravel; 5 percent cobbles; neutral Content of rock fragments: 5 to 35 percent—0 to (pH 6.8); clear smooth boundary. 10 percent stones and cobbles; 5 to 25 percent Bt3—19 to 27 inches; light olive brown (2.5Y 5/3) gravel clay, dark grayish brown (2.5Y 4/2) moist; strong Reaction: pH 6.6 to 7.8 medium prismatic structure; extremely hard, extremely firm, very sticky, very plastic; few very Btk horizon fine and fine roots; few very fine pores; common Hue: 7.5YR, 10YR, or 2.5Y prominent continuous dark yellowish brown (2.5Y Value: 5 or 6 dry; 4 or 5 moist 4/2) moist; clay films on faces of peds; 5 percent Chroma: 2 to 4 46 Soil Survey

Texture (less than 2 mm): Clay loam or clay medium subangular blocky structure; soft, very Clay content: 27 to 40 percent friable, slightly sticky, slightly plastic; common Content of rock fragments: 5 to 35 percent—0 to very fine and fine roots; many very fine and fine 10 percent stones and cobbles; 5 to 25 percent pores; few fine soft masses of lime; 5 percent gravel channers; strongly effervescent; moderately Calcium carbonate equivalent: 3 to 12 percent alkaline (pH 8.0); clear smooth boundary. Reaction: pH 7.4 to 7.8 Bk2—9 to 15 inches; light olive gray (5Y 6/2) gravelly loam, olive gray (5Y 5/2) moist; weak coarse Bk horizon prismatic structure; soft; very friable, slightly Hue: 7.5YR, 10YR, or 2.5Y sticky, slightly plastic; common very fine and fine Value: 6 to 8 dry; 5 to 7 moist roots; common very fine and fine pores; common Chroma: 2 to 4 fine soft masses of lime; 20 percent gravel; Texture (less than 2 mm): Clay loam, sandy clay strongly effervescent; moderately alkaline loam, or loam (pH 8.0); clear smooth boundary. Clay content: 18 to 35 percent Cr—15 to 60 inches; soft sedimentary sandstone and Content of rock fragments: 5 to 35 percent—0 to siltstone beds that crush to a loam; strongly 20 percent stones and cobbles; 5 to 30 percent effervescent. gravel Calcium carbonate equivalent: 5 to 15 percent Range in Characteristics Reaction: pH 7.4 to 9.0 Soil temperature: 41 to 47 degrees F Cabba Series Moisture control section: Between 4 and 12 inches Depth to the Cr horizon: 10 to 20 inches Depth class: Shallow (10 to 20 inches) A horizon Drainage class: Well drained Hue: 10YR or 2.5Y Permeability: Moderate (0.6 to 2.0 inches/hour) Value: 3 to 6 dry; 3 or 4 moist Landform: Escarpment, hill, and knoll on plain Chroma: 1 to 3 Parent material: Loamy residuum weathered from Texture (less than 2 mm): Loam or clay loam sandstone and siltstone Clay content: 10 to 35 percent Slope range: 2 to 60 percent Content of rock fragments: 0 to 60 percent—0 to Elevation range: 3,900 to 6,200 feet 30 percent stones and cobbles; 0 to 30 percent Mean annual precipitation: 15 to 20 inches gravel or channers Mean annual air temperature: 39 to 45 degrees F Calcium carbonate equivalent: 0 to 10 percent Frost-free period: 70 to 115 days Reaction: pH 6.6 to 9.0 Taxonomic Class: Loamy, mixed, superactive, Bk horizons calcareous, frigid, shallow Typic Ustorthents Hue: 10YR, 2.5Y, or 5Y Value: 5 to 8 dry; 4 to 6 moist Typical Pedon Chroma: 1 to 4 Cabba loam, in an area of Cabba-Doney loams, 8 to Texture (less than 2 mm): Loam or clay loam 35 percent slopes, in an area of rangeland, 1,300 feet Clay content: 20 to 35 percent south and 1,600 feet east of the northwest corner of Content of rock fragments: 0 to 35 percent—0 to sec. 21, T. 3 N., R. 13 E.; USGS Grosfield Ranch 5 percent cobbles; 0 to 30 percent gravel or topographic quadrangle (lat. 45o59'47" N.; long. channers 110o07'06" W.) Calcium carbonate equivalent: 2 to 15 percent Reaction: pH 7.4 to 9.0 A—0 to 4 inches; grayish brown (2.5Y 5/2) loam, dark grayish brown (2.5Y 4/2) moist; weak medium platy structure parting to weak fine granular; soft, Cabbart Series very friable, slightly sticky, slightly plastic; common very fine and fine roots; many very fine Depth class: Shallow (10 to 20 inches) and fine pores; slightly effervescent; slightly Drainage class: Well drained alkaline (pH 7.8); clear smooth boundary. Permeability: Moderate (0.6 to 2.0 inches/hour) Bk1—4 to 9 inches; light brownish gray (2.5Y 6/2) Landform: Escarpment, hill, strath terrace, and knoll loam, dark grayish brown (2.5Y 4/2) moist; weak on plain Sweet Grass County Area, Montana—Part I 47

Parent material: Loamy residuum weathered from A horizon sandstone and siltstone Hue: 10YR, 2.5Y, or 5Y Slope range: 2 to 60 percent Value: 5 to 7 dry; 3 to 5 moist Elevation range: 3,750 to 5,200 feet Chroma: 2 or 3 Mean annual precipitation: 10 to 14 inches Texture (less than 2 mm): Loam Mean annual air temperature: 43 to 46 degrees F Clay content: 18 to 27 percent Frost-free period: 95 to 125 days Content of rock fragments: 0 to 60 percent—0 to 20 percent cobbles; 0 to 40 percent gravel Taxonomic Class: Loamy, mixed, superactive, Calcium carbonate equivalent: 5 to 10 percent calcareous, frigid, shallow Aridic Ustorthents Reaction: pH 7.4 to 9.0 Typical Pedon Bk horizons Hue: 10YR, 2.5Y, or 5Y Cabbart loam, in an area of grassland, 1,200 feet Value: 5 to 8 dry; 4 to 6 moist north and 2,450 feet east of the southwest corner of Chroma: 2 to 4 sec. 7, T. 20 N., R. 3 W.; Cascade County, Montana. Texture (less than 2 mm): Loam, clay loam, silt A—0 to 3 inches; light brownish gray (2.5Y 6/2) loam, loam, or silty clay loam dark grayish brown (2.5Y 4/2) moist; weak fine Clay content: 18 to 35 percent granular structure; slightly hard, very friable, Content of rock fragments: 0 to 45 percent—0 to slightly sticky, slightly plastic; many fine roots and 15 percent hard gravel; 0 to 45 percent soft pores; strongly effervescent; moderately alkaline gravel (pH 8.4); clear wavy boundary. Calcium carbonate equivalent: 10 to 25 percent Bk1—3 to 7 inches; light brownish gray (2.5Y 6/2) Reaction: pH 7.4 to 9.0 loam, grayish brown (2.5Y 5/2) moist; weak BC horizon medium prismatic structure; hard, very friable, Hue: 10YR, 2.5Y, or 5Y slightly sticky, slightly plastic; many fine roots and Value: 5 to 8 dry; 4 to 6 moist pores; few fine masses of lime; strongly Chroma: 2 to 4 effervescent; moderately alkaline (pH 8.4); clear Texture (less than 2 mm): Loam, clay loam, silt wavy boundary. loam, or silty clay loam Bk2—7 to 16 inches; pale yellow (2.5Y 7/4) loam, Clay content: 18 to 35 percent light yellowish brown (2.5Y 6/4) moist; weak Content of rock fragments: 0 to 45 percent—0 to coarse prismatic structure; hard, very friable, 15 percent hard gravel; 0 to 45 percent soft slightly sticky, slightly plastic; many fine roots and gravel pores; common fine masses of lime; strongly Calcium carbonate equivalent: 5 to 25 percent effervescent; moderately alkaline (8.4); clear Reaction: pH 7.4 to 9.0 wavy boundary. BC—16 to 18 inches; pale yellow (2.5Y 7/4) loam, light yellowish brown (2.5Y 6/4) moist; weak coarse prismatic structure; very hard, friable, Cambeth Series slightly sticky, slightly plastic; many fine roots and Depth class: Moderately deep (20 to 40 inches) pores; disseminated lime; strongly effervescent; Drainage class: Well drained moderately alkaline (pH 8.4); clear wavy Permeability: Moderate (0.6 to 2.0 inches/hour) boundary. Landform: Hill Cr—18 to 60 inches; pale yellow (5Y 7/4) Parent material: Silty residuum weathered from semiconsolidated loamy sedimentary beds that sandstone and siltstone crush to loam; few widely spaced vertical cracks Slope range: 4 to 15 percent in upper 4 to 6 inches with roots; root mat at Elevation range: 3,750 to 5,200 feet contact of beds. Mean annual precipitation: 10 to 14 inches Range in Characteristics Mean annual air temperature: 40 to 45 degrees F Frost-free period: 95 to 125 days Soil temperature: 42 to 47 degrees F Moisture control section: Between 4 and 12 inches Depth to the Cr horizon: 10 to 20 inches Taxonomic Class: Fine-silty, mixed, superactive, Note: Some pedons do not have a BC horizon. frigid Aridic Calciustepts 48 Soil Survey

Typical Pedon Bk horizon Hue: 10YR, 2.5Y, or 5Y Cambeth silt loam, in an area of Cabbart-Cambeth Value: 5 to 7 dry; 4 to 6 moist; complex, 4 to 35 percent slopes, in an area of Chroma: 2 to 4 rangeland, 1,700 feet south and 2,400 feet east of the Texture (less than 2 mm): Silt loam, silty clay northwest corner of sec. 8, T. 2 N., R. 18 E.; USGS loam, or loam Stephens Hill NE topographic quadrangle (lat. Clay content: 18 to 35 percent 45o56'20" N.; long. 109o31'03" W.) Calcium carbonate equivalent: 10 to 20 percent A—0 to 4 inches; grayish brown (10YR 5/2) silt loam, Reaction: pH 7.9 to 9.0 dark grayish brown (10YR 4/2) moist; weak fine granular structure; soft, very friable, slightly sticky, slightly plastic; common very fine and fine roots; Castner Series many fine pores; slightly alkaline (pH 7.4); clear Depth class: Shallow (10 to 20 inches) smooth boundary. Drainage class: Well drained Bw—4 to 13 inches; light brownish gray (2.5Y 6/2) silt Permeability: Moderate (0.6 to 2.0 inches/hour) loam, grayish brown (2.5Y 5/2) moist; weak fine Landform: Escarpment, hill, terrace, and knoll on subangular blocky structure; soft, very friable, plain slightly sticky, slightly plastic; common fine and Parent material: Residuum weathered from medium roots; common fine pores; slightly sandstone effervescent; slightly alkaline (pH 7.8); clear Slope range: 0 to 60 percent smooth boundary. Elevation range: 3,900 to 6,200 feet Bk—13 to 24 inches; light brownish gray (2.5Y 6/2) Mean annual precipitation: 15 to 20 inches silt loam, grayish brown (2.5Y 5/2) moist; weak Mean annual air temperature: 39 to 45 degrees F coarse prismatic structure; soft, very friable, Frost-free period: 70 to 115 days slightly sticky, slightly plastic; few medium roots; common fine pores; few soft masses of lime; Taxonomic Class: Loamy-skeletal, mixed, strongly effervescent; moderately alkaline superactive, frigid Lithic Haplustolls (pH 8.4); clear smooth boundary. Cr—24 to 60 inches; weakly consolidated siltstone Typical Pedon that crushes to silt loam; strongly effervescent. Castner channery loam, in an area of Castner- Range in Characteristics Absarokee complex, 2 to 8 percent slopes, in an area of rangeland, 1,200 feet north and 400 feet east of Soil temperature: 42 to 47 degrees F the southwest corner of sec. 13, T. 1 S., R. 15 E.; Moisture control section: Between 4 and 12 inches USGS Packsaddle Butte topographic quadrangle Depth to the Bk horizon: 10 to 15 inches (lat. 45o44'38" N.; long. 109o49'33" W.) Depth to the Cr horizon: 20 to 40 inches A1—0 to 5 inches; dark grayish brown (10YR 4/2) A horizon channery loam, dark brown (10YR 3/3) moist; Hue: 10YR or 2.5Y moderate fine granular structure; soft, very Value: 4 to 6 dry; 3 or 4 moist friable, slightly sticky, slightly plastic; many Chroma: 2 to 4 very fine and fine roots; many very fine pores; Texture (less than 2 mm): Silt loam 5 percent flagstones; 15 percent channers; Clay content: 18 to 27 percent neutral (pH 7.2); abrupt smooth boundary. Calcium carbonate equivalent: 0 to 10 percent A2—5 to 10 inches; brown (10YR 4/3) very channery Reaction: pH 6.6 to 7.8 loam, dark brown (10YR 3/3) moist; weak Bw horizon medium subangular blocky structure parting to Hue: 10YR or 2.5Y moderate fine granular; slightly hard, friable, Value: 5 to 7 dry; 4 or 5 moist slightly sticky, slightly plastic; few fine and many Chroma: 2 to 4 very fine roots; many very fine and fine pores; Texture (less than 2 mm): Silt loam, silty clay 5 percent cobbles; 50 percent channers; slightly loam, or loam effervescent on undersides of channers; neutral Clay content: 18 to 35 percent (pH 7.2); clear smooth boundary. Calcium carbonate equivalent: 0 to 10 percent Bk—10 to 18 inches; light brownish gray (10YR 6/2) Reaction: pH 7.4 to 8.4 extremely channery loam, grayish brown (10YR Sweet Grass County Area, Montana—Part I 49

5/2) moist; moderate medium subangular blocky Cheadle Series structure; slightly hard, friable, slightly sticky, slightly plastic; few very fine roots; few very fine Depth class: Shallow (10 to 20 inches) pores; few fine threads of lime; few carbonate Drainage class: Well drained coats on undersides of channers; 10 percent Permeability: Moderate (0.6 to 2.0 inches/hour) flagstones; 55 percent channers; strongly Landform: Mountain effervescent; slightly alkaline (pH 7.8); abrupt Parent material: Residuum weathered from smooth boundary. sandstone or gabbro R—18 inches; hard fractured noncalcareous Slope range: 2 to 70 percent sandstone. Elevation range: 5,500 to 7,500 feet Mean annual precipitation: 20 to 25 inches Range in Characteristics Mean annual air temperature: 36 to 38 degrees F Soil temperature: 38 to 47 degrees F Frost-free period: 50 to 70 days Moisture control section: Between 4 and 12 inches Thickness of the mollic epipedon: 7 to 15 inches Taxonomic Class: Loamy-skeletal, mixed, Depth to bedrock: 10 to 20 inches superactive Lithic Haplocryolls A1 horizon Typical Pedon Hue: 7.5YR, 10YR, or 2.5Y Cheadle channery loam, in an area of Cheadle Value: 3 to 5 dry; 2 or 3 moist channery loam, 2 to 15 percent slopes, in an area of Chroma: 1 to 3 rangeland, 2,200 feet north and 1,800 feet west of Texture (less than 2 mm): Loam or sandy loam the southeast corner of sec. 36, T. 2 S., R. 12 E.; Clay content: 10 to 18 percent USGS McLeod Basin topographic quadrangle (lat. Content of rock fragments: 5 to 45 percent—0 to 45o36'54" N.; long. 110o10'57" W.) 25 percent stones, flagstones, or cobbles; 5 to 30 percent gravel or channers A1—0 to 5 inches; dark grayish brown (10YR 4/2) Reaction: pH 6.6 to 7.8 channery loam, very dark brown (10YR 2/2) moist; weak fine granular structure; soft, very A2 horizon friable, slightly sticky, slightly plastic; many very Hue: 7.5YR, 10YR, or 2.5Y fine and fine roots; many very fine and fine pores; Value: 3 to 5 dry; 2 or 3 moist 25 percent channers; 5 percent flagstones; Chroma: 1 to 3 neutral (pH 6.8); abrupt smooth boundary. Texture (less than 2 mm): Loam or sandy loam A2—5 to 11 inches; grayish brown (10YR 5/2) very Clay content: 10 to 18 percent channery fine sandy loam, very dark grayish Content of rock fragments: 35 to 70 percent—5 to brown (10YR 3/2) moist; weak medium granular 20 percent stones, flagstones, or cobbles; structure; soft, very friable, slightly sticky, 35 to 55 percent gravel or channers nonplastic; many very fine and fine roots; many Calcium carbonate equivalent: 0 to 5 percent very fine and fine pores; slightly effervescent; Reaction: pH 6.6 to 8.4 10 percent gravel; 20 percent channers; Bk horizon 10 percent flagstones; slightly alkaline (pH 7.4); Hue: 7.5YR, 10YR, or 2.5Y clear smooth boundary. Value: 4 to 6 dry; 3 to 5 moist Bk—11 to 14 inches; light brownish gray (10YR 6/2) Chroma: 2 or 3 extremely flaggy fine sandy loam, dark grayish Texture (less than 2 mm): Loam or sandy loam brown (10YR 4/2) moist; weak medium Clay content: 10 to 18 percent subangular blocky structure; soft, very friable, Content of rock fragments: 35 to 80 percent— slightly sticky, nonplastic; many very fine and fine 10 to 25 percent stones, flagstones, or roots; many very fine and fine pores; cobbles; 25 to 60 percent gravel or channers discontinuous carbonate coats on rock Calcium carbonate equivalent: 3 to 15 percent fragments; strongly effervescent; 20 percent Reaction: pH 6.6 to 8.4 gravel; 15 percent channers; 30 percent 50 Soil Survey

flagstones; slightly alkaline (pH 7.8); abrupt Parent material: Sandy residuum weathered from smooth boundary. sandstone R—14 inches; hard sandstone. Slope range: 4 to 25 percent Elevation range: 3,750 to 5,200 feet Range in Characteristics Mean annual precipitation: 10 to 14 inches Soil temperature: 37 to 47 degrees F Mean annual air temperature: 43 to 46 degrees F Moisture control section: Between 4 and 12 inches Frost-free period: 95 to 125 days Thickness of the mollic epipedon: 7 to 16 inches Depth to the Bk horizon: 7 to 16 inches Taxonomic Class: Coarse-loamy, mixed, Depth to bedrock: 10 to 20 inches superactive, frigid Aridic Haplustolls A1 horizon Typical Pedon Hue: 7.5YR, 10YR, or 2.5Y Chinook fine sandy loam, in an area of Chinook- Value: 3 to 5 dry; 2 or 3 moist Twilight fine sandy loams, 8 to 25 percent slopes, in Chroma: 1 or 2 an area of rangeland, 2,500 feet north and 1,000 feet Texture (less than 2 mm): Loam east of the southwest corner of sec. 8, T. 5 N., Clay content: 10 to 27 percent R. 15 E.; USGS Melville NW topographic quadrangle Content of rock fragments: 0 to 60 percent—0 to (lat. 46o11'51" N.; long. 109o52'44" W.) 50 percent stones, flagstones or cobbles, and channers; 0 to 10 percent gravel A1—0 to 3 inches; grayish brown (10YR 5/2) fine Reaction: pH 6.6 to 7.8 sandy loam, very dark brown (10YR 2/2) moist; moderate very fine and fine granular structure; A2 horizon soft, very friable, nonsticky, nonplastic; common Hue: 7.5YR, 10YR, or 2.5Y medium and coarse and many very fine and fine Value: 4 or 5 dry; 2 or 3 moist roots; many very fine and fine pores; neutral Chroma: 1 to 3 (pH 6.8); clear wavy boundary. Texture (less than 2 mm): Fine sandy loam, loam, A2—3 to 10 inches; grayish brown (10YR 5/2) sandy or sandy loam loam, very dark grayish brown (10YR 3/2) moist; Clay content: 10 to 27 percent weak medium subangular blocky structure Content of rock fragments: 35 to 75 percent—0 to parting to moderate very fine and fine granular; 65 percent stones, flagstones or cobbles, and soft, very friable, nonsticky, nonplastic; common channers; 10 to 30 percent gravel fine and medium and many very fine roots; many Calcium carbonate equivalent: 0 to 5 percent very fine and fine pores; neutral (pH 7.2); gradual Reaction: pH 7.4 to 9.0 wavy boundary. Bk horizon Bw1—10 to 20 inches; light olive brown (2.5Y 5/3) Hue: 7.5YR, 10YR, or 2.5Y sandy loam, olive brown (2.5Y 4/3) moist; weak Value: 5 or 6 dry; 4 or 5 moist fine subangular blocky structure; soft, very friable, Chroma: 2 to 4 nonsticky, nonplastic; few very fine and fine roots; Texture (less than 2 mm): Fine sandy loam, loam, many very fine and fine pores; slightly alkaline or sandy loam (pH 7.4); gradual wavy boundary. Clay content: 10 to 27 percent Bw2—20 to 31 inches; light yellowish brown (2.5Y Content of rock fragments: 35 to 75 percent—0 to 6/3) sandy loam, light olive brown (2.5Y 5/3) 65 percent stones, flagstones or cobbles, and moist; weak very fine and fine subangular blocky channers; 20 to 30 percent gravel structure; soft, very friable, nonsticky, nonplastic; Calcium carbonate equivalent: 3 to 10 percent few very fine roots; many very fine and fine pores; Reaction: pH 7.4 to 9.0 slightly alkaline (pH 7.4); gradual wavy boundary. Bk1—31 to 45 inches; light brownish gray (2.5Y 6/2) sandy loam, light olive brown (2.5Y 5/3) moist; Chinook Series weak very fine subangular blocky structure; soft, very friable, nonsticky, nonplastic; few very fine Depth class: Very deep (greater than 60 inches) roots; common very fine and fine pores; common Drainage class: Well drained fine irregular soft masses of lime; strongly Permeability: Moderately rapid (2 to 6 inches/hour) effervescent; moderately alkaline (pH 8.4); Landform: Hill and swale on plain gradual wavy boundary. Sweet Grass County Area, Montana—Part I 51

Bk2—45 to 60 inches; light brownish gray (2.5Y 6/2) Bk2 horizon sandy loam, light olive brown (2.5Y 5/3) moist; Hue: 10YR, 2.5Y, or 5Y weak coarse subangular blocky structure; slightly Value: 5 to 7 dry; 4 to 6 moist hard, friable, nonsticky, nonplastic; few very fine Chroma: 2 to 4 roots; common very fine and fine pores; common Texture (less than 2 mm): Sandy loam or fine fine irregular soft masses of lime; strongly sandy loam effervescent; moderately alkaline (pH 8.4). Clay content: 5 to 18 percent Content of rock fragments: 0 to 15 percent gravel Range in Characteristics Calcium carbonate equivalent: 5 to 15 percent Reaction: pH 6.6 to 9.0 Soil temperature: 42 to 47 degrees F Moisture control section: Between 8 and 24 inches Thickness of the mollic epipedon: 7 to 15 inches Depth to the Bk horizon: 10 to 35 inches Clunton Series Note: Some pedons have a BC horizon of loamy sand Depth class: Very deep (greater than 60 inches) or loamy fine sand. Drainage class: Very poorly drained A1 horizon Landform: Depression on flood plain Hue: 10YR or 2.5Y Parent material: Fine-loamy over sandy and gravelly Value: 5 dry; 2 or 3 moist alluvium Chroma: 2 or 3 Slope range: 0 to 4 percent Texture (less than 2 mm): Fine sandy loam Elevation range: 3,750 to 6,000 feet Clay content: 5 to 18 percent Mean annual precipitation: 10 to 19 inches Content of rock fragments: 0 to 35 percent gravel Mean annual air temperature: 43 to 46 degrees F Reaction: pH 6.6 to 8.4 Frost-free period: 85 to 130 days A2 horizon Taxonomic Class: Fine-Loamy, mixed, superactive, Hue: 10YR or 2.5Y frigid Fluvaquentic Endoaquolls Value: 4 or 5 dry; 2 to 4 moist Chroma: 2 or 3 Typical Pedon Texture (less than 2 mm): Sandy loam or fine sandy loam Clunton silty clay loam, 1,600 feet north and Clay content: 5 to 18 percent 1,200 feet west of the southeast corner of sec. 30, Content of rock fragments: 0 to 35 percent gravel T. 4 N., R. 2 W.; Jefferson County, Montana. Reaction: pH 6.6 to 8.4 Oa—0 to 4 inches; very dark gray (5Y 3/1) muck, very Bw horizons dark gray (5Y 3/1) dry; neutral (pH 6.8); clear Hue: 10YR or 2.5Y smooth boundary. Value: 4 to 6 dry; 3 to 5 moist Ag—4 to 18 inches; very dark gray (10YR 3/1) silty Chroma: 2 to 4 clay loam, dark gray (10YR 4/1) dry; many Texture (less than 2 mm): Sandy loam or fine distinct black (5Y 2.5/1) redox depletions; few sandy loam faint strong brown (7.5YR 5/6) redox Clay content: 5 to 18 percent concentrations; moderate medium prismatic Content of rock fragments: 0 to 15 percent gravel structure; hard, firm, moderately sticky, Reaction: pH 6.6 to 8.4 moderately plastic; common very fine roots; Bk1 horizon common very fine and fine interstitial pores; Hue: 10YR, 2.5Y, or 5Y neutral (pH 7.0); abrupt smooth boundary. Value: 5 to 7 dry; 4 or 5 moist Cg1—18 to 30 inches; very dark gray (5Y 3/1) silty Chroma: 2 to 4 clay loam, dark gray (5Y 4/1) dry; common faint Texture (less than 2 mm): Sandy loam or fine very dark gray (5Y 3/1) redox depletions; many sandy loam distinct strong brown (7.5YR 5/6) redox Clay content: 5 to 18 percent concentrations; massive; hard, firm, moderately Content of rock fragments: 0 to 15 percent gravel sticky, moderately plastic; common very fine Calcium carbonate equivalent: 3 to 12 percent roots; few very fine tubular pores; neutral (pH Reaction: pH 6.6 to 9.0 7.2); clear wavy boundary. 52 Soil Survey

Cg2—30 to 34 inches; very dark gray (5Y 3/1) loam Texture (less than 2 mm): Loam, clay loam, or consisting of strata of loam and sandy loam, dark silty clay loam gray (5Y 4/1) dry; common distinct strong brown Clay content: 18 to 35 percent (7.5YR 5/6) redox concentrations; common faint Content of rock fragments: 0 to 10 percent gravel very dark gray (5Y 3/1) redox depletions; Electrical conductivity: 0 to 2 mmhos/cm massive; hard, friable, slightly sticky, slightly Reaction: pH 6.6 to 7.8 plastic; few very fine roots; neutral (pH 7.2); Cg2 and Cg3 horizons gradual wavy boundary. Hue: 2.5Y or 5Y Cg3—34 to 42 inches; dark gray (5Y 4/1) silty clay Value: 4 to 6 dry; 3 to 5 moist loam consisting of strata of silty clay loam and Redox concentrations: Few to common; 7.5YR sandy loam, gray (5Y 5/1) dry; common distinct 5/6 or 5YR 5/6 strong brown (7.5YR 5/6) redox concentrations; Redox depletions: Common or many; 10YR 4/1, common faint very dark gray (5Y 3/1) redox 10YR 3/1, 5Y 3/1, or 5Y 4/1 depletions; massive; slightly hard, friable, slightly Texture (less than 2 mm): Silt loam, loam, clay sticky, slightly plastic; neutral (pH 7.0); gradual loam, or silty clay loam with thin strata of finer wavy boundary. and coarser materials 2Cg4—42 to 64 inches; dark gray (10YR 4/1) gravelly Clay content: 18 to 35 percent sandy loam, grayish brown (2.5Y 5/2) dry; many Content of rock fragments: 0 to 10 percent gravel distinct strong brown (7.5YR 5/6) redox Electrical conductivity: 0 to 2 mmhos/cm concentrations; few faint very dark gray (5Y 3/1) Reaction: pH 6.6 to 7.8 redox depletions; massive; slightly hard, friable, slightly sticky, nonplastic; 15 percent gravel; 2Cg4 horizon neutral (pH 7.0). Hue: 10YR, 2.5Y, 5Y, or N Value: 4 or 5 dry; 3 or 4 moist Range in Characteristics Chroma: 0 to 2 Redox concentrations: Common or many; 7.5YR Soil temperature: 40 to 46 degrees F 5/6 or 5YR 5/6 Moisture control section: Between 4 and 12 inches Redox depletions: Few to many; 10YR 4/1, 10YR Thickness of the mollic epipedon: 10 to 24 inches 3/1, 5Y 3/1, or 5Y 4/1 Depth to the seasonal high water table: 0 to Texture (less than 2 mm): Sandy loam or loam 12 inches for extended periods during spring with strata of loamy sand, silt loam, or very fine and summer sandy loam Clay content (weighted average in particle-size Clay content: 5 to 25 percent control section): 18 to 27 percent Content of rock fragments: 0 to 25 percent gravel Electrical conductivity: 0 to 2 mmhos/cm Ag horizon Reaction: pH 6.6 to 7.8 Hue: 10YR, 2.5Y, or 5Y Value: 4 or 5 dry; 3 or 4 moist Chroma: 1 or 2 Cowood Series Redox concentrations: Few to common; 7.5YR Depth class: Shallow (10 to 20 inches) 5/6 or 5YR 5/6 Drainage class: Well drained Redox depletions: Common or many 10YR 4/1, Permeability: Moderate (0.6 to 2.0 inches/hour) 10YR 3/1, 5Y 3/1, 5Y 2.5/1 or 5Y 4/1 Landform: Mountain Texture (less than 2 mm): Clay loam or loam Parent material: Residuum weathered from Clay content: 20 to 30 percent sandstone over gabbro or residuum weathered Reaction: pH 6.1 to 7.3 from gabbro Cg1 horizon Slope range: 4 to 60 percent Hue: 10YR, 2.5Y, or 5Y Elevation range: 5,500 to 7,500 feet Value: 3 to 5 moist Mean annual precipitation: 20 to 25 inches Chroma: 1 or 2 Mean annual air temperature: 36 to 38 degrees F Redox concentrations: Few to common; 7.5YR Frost-free period: 50 to 70 days 5/6 or 5YR 5/6 Redox depletions: Common or many; 10YR 4/1, Taxonomic Class: Loamy-skeletal, mixed, 10YR 3/1, 5Y 3/1, or 5Y 4/1 superactive Lithic Eutrocryepts Sweet Grass County Area, Montana—Part I 53

Typical Pedon Content of rock fragments: 60 to 80 percent stones, cobbles, gravel, or channers Cowood very channery loam, in an area of Cowood Reaction: pH 5.1 to 6.5 very channery loam, 4 to 25 percent slopes, in an area of coniferous forest, 1,700 feet north and 200 feet west of the southeast corner of sec. 1, Creed Series T. 3 S., R. 13 E.; USGS Squaw Peak topographic quadrangle (lat. 45o36'05" N.; long. 110o03'15" W.) Depth class: Very deep (greater than 60 inches) Drainage class: Well drained Oi—0 to 3 inches; slightly decayed needles, twigs, Permeability: Slow (0.06 to 0.20 inch/hour) and leaves; moderately acid (pH 6.0); abrupt Landform: Plain, stream terrace, depression on fan, smooth boundary. and depression on terrace E—3 to 8 inches; grayish brown (10YR 5/2) very Parent material: Clayey alluvium channery loam, dark grayish brown (10YR 4/2) Slope range: 0 to 8 percent moist; weak medium platy structure parting to Elevation range: 3,750 to 5,200 feet weak fine granular; soft, very friable, slightly Mean annual precipitation: 10 to 14 inches sticky, nonplastic; many very fine and fine roots; Mean annual air temperature: 43 to 46 degrees F many very fine and fine pores; 30 percent Frost-free period: 95 to 125 days channers; 10 percent cobbles; moderately acid (pH 6.0); clear smooth boundary. Taxonomic Class: Fine, smectitic, frigid Aridic Bw—8 to 19 inches; brown (10YR 5/3) extremely Natrustalfs channery loam, dark brown (10YR 4/3) moist; weak medium subangular blocky structure Typical Pedon parting to weak fine granular; soft, very friable, Creed loam, in an area of Gerdrum-Creed complex, slightly sticky, nonplastic; many fine and medium 0 to 8 percent slopes, in an area of rangeland, roots; many very fine and fine pores; 45 percent 2,200 feet north and 2,350 feet east of the southwest channers; 20 percent cobbles; moderately acid corner of sec. 12, T. 3 N., R. 18 E.; USGS Locomotive (pH 6.0); abrupt smooth boundary. Butte topographic quadrangle (lat. 46o01'28" N.; long. R—19 inches; fine-grained gabbro. 109o26'01" W.) Range in Characteristics A—0 to 2 inches; grayish brown (10YR 5/2) loam, Soil temperature: 35 to 40 degrees F dark grayish brown (10YR 4/2) moist; weak fine Moisture control section: Between 4 and 12 inches granular structure; soft, very friable, slightly sticky, Depth to bedrock: 10 to 20 inches slightly plastic; many very fine and fine roots; Note: Some pedons have an A horizon in place of the many very fine and fine pores; neutral (pH 7.0); E horizon. clear smooth boundary. E—2 to 5 inches; light brownish gray (10YR 6/2) E horizon loam, dark grayish brown (10YR 4/2) moist; weak Hue: 10YR or 2.5Y thin and medium platy structure; soft, very friable, Value: 5 or 6 dry; 2 to 5 moist slightly sticky, slightly plastic; many very fine and Chroma: 2 or 3 fine roots; many very fine and fine pores; neutral Texture (less than 2 mm): Loam (pH 7.0); abrupt smooth boundary. Clay content: 10 to 20 percent Btn1—5 to 9 inches; brown (10YR 5/3) clay loam, Content of rock fragments: 35 to 70 percent— dark brown (10YR 4/3) moist; moderate medium 10 to 50 percent stones and cobbles; 15 to and coarse angular blocky structure; very hard, 50 percent gravel or channers firm, moderately sticky, moderately plastic; many Reaction: pH 5.1 to 6.0 very fine and fine roots; many very fine and fine Bw horizon pores; many faint discontinuous olive brown (2.5Y Hue: 10YR or 2.5Y 4/3) moist; clay films on faces of peds and lining Value: 5 or 6 dry; 4 or 5 moist pores; slightly alkaline (pH 7.4); clear smooth Chroma: 3, 4, or 6 boundary. Texture (less than 2 mm): Loam Btn2—9 to 14 inches; pale brown (10YR 6/3) silty Clay content: 10 to 20 percent clay, brown (10YR 4/3) moist; moderate medium 54 Soil Survey

prismatic structure parting to moderate medium Chroma: 2 or 3 and coarse angular blocky; very hard, firm, very Texture (less than 2 mm): Loam sticky, very plastic; common very fine and fine Clay content: 20 to 27 percent roots; common very fine and fine pores; many Content of rock fragments: 0 to 15 percent gravel distinct discontinuous dark olive brown (2.5Y Reaction: pH 6.1 to 8.4 3/3), moist; clay films on faces of peds and lining Btn horizons pores; slightly alkaline (pH 7.4); abrupt smooth Hue: 10YR, 2.5Y, or 5Y boundary. Value: 4 to 6 dry; 3 to 5 moist Btnk—14 to 22 inches; light brownish gray (2.5Y 6/2) Chroma: 2 or 3 clay loam, grayish brown (2.5Y 5/2) moist; Texture (less than 2 mm): Clay loam, clay, silty moderate coarse prismatic structure parting to clay, or silty clay loam weak coarse angular blocky; very hard, friable, Clay content: 35 to 55 percent moderately sticky, moderately plastic; common Content of rock fragments: 0 to 15 percent gravel very fine and fine roots; common very fine and Electrical conductivity: 2 to 4 mmhos/cm fine pores; few distinct patchy olive brown (2.5Y Sodium adsorption ratio: 8 to 13 4/3) moist; clay films on faces of peds; few fine Reaction: pH 6.6 to 9.0 soft masses of lime; strongly effervescent; moderately alkaline (pH 8.0); gradual smooth Btnk and Bky horizons boundary. Hue: 10YR, 2.5Y, or 5Y Bky—22 to 32 inches; light brownish gray (2.5Y 6/2) Value: 5 to 7 dry; 4 to 6 moist clay loam, grayish brown (2.5Y 5/2) moist; weak Chroma: 2 to 4 coarse prismatic structure; very hard, friable, Texture (less than 2 mm): Clay loam, silty clay, moderately sticky, moderately plastic; few fine silty clay loam, loam, or clay and medium roots; few very fine and fine pores; Clay content: 25 to 45 percent few fine and medium masses of gypsum; Content of rock fragments: 0 to 15 percent gravel common fine and medium soft masses of lime; Calcium carbonate equivalent: 5 to 15 percent strongly effervescent moderately alkaline Electrical conductivity: 4 to 8 mmhos/cm (pH 8.4); gradual smooth boundary. Sodium adsorption ratio: 13 to 20 Byz—32 to 60 inches; light gray (2.5Y 7/2) clay loam, Gypsum content: 0 to 2 percent light brownish gray (2.5Y 6/2) moist; weak coarse Reaction: pH 7.9 to 9.0 prismatic structure; very hard, friable, moderately Byz horizon sticky, moderately plastic; many medium and Hue: 10YR, 2.5Y, or 5Y coarse masses of gypsum; common medium Value: 5 to 7 dry; 4 to 6 moist and coarse masses of salt; few fine soft masses Chroma: 2 to 4 of lime; strongly effervescent; strongly alkaline Texture (less than 2 mm): Clay loam, silty clay (pH 8.6). loam, sandy clay loam, or loam Range in Characteristics Clay content: 25 to 35 percent Content of rock fragments: 0 to 15 percent gravel Soil temperature: 42 to 47 degrees F Calcium carbonate equivalent: 5 to 10 percent Moisture control section: Between 4 and 12 inches Electrical conductivity: 4 to 16 mmhos/cm Depth to the Btnk horizon: 10 to 20 inches Sodium adsorption ratio: 13 to 25 Depth to the Bky horizon: 22 to 30 inches Gypsum content: 1 to 5 percent A horizon Reaction: pH 7.9 to 9.0 Hue: 10YR, 2.5Y, or 5Y Value: 5 or 6 dry; 3 to 5 moist Chroma: 2 or 3 Danaher Series Texture (less than 2 mm): Loam Depth class: Very deep (greater than 60 inches) Clay content: 20 to 27 percent Drainage class: Well drained Content of rock fragments: 0 to 15 percent gravel Permeability: Slow (0.06 to 0.20 inches/hour) Reaction: pH 6.1 to 8.4 Landform: Mountain E horizon Parent material: Silty and clayey alluvium or colluvium Hue: 10YR, 2.5Y, or 5Y Slope range: 15 to 60 percent Value: 5 to 7 dry; 4 to 6 moist Elevation range: 5,500 to 7,500 feet Sweet Grass County Area, Montana—Part I 55

Mean annual precipitation: 20 to 25 inches very plastic; few coarse roots; common very fine Mean annual air temperature: 36 to 38 degrees F and fine pores; common faint dark reddish brown Frost-free period: 50 to 70 days (5YR 3/4) moist; clay films on faces of peds; 15 percent gravel; 10 percent cobbles; Taxonomic Class: Fine, mixed, superactive Ustic moderately acid (pH 5.8); clear wavy boundary. Glossocryalfs Bt3—41 to 60 inches; light reddish brown (5YR 6/4) gravelly clay loam; reddish brown (5YR 4/4) Typical Pedon moist; weak medium prismatic structure parting Danaher loam, in an area of Danaher-Timberlin to weak medium subangular blocky; slightly hard, complex, 25 to 60 percent slopes, in an area of firm, very sticky, very plastic; few coarse roots; coniferous forest, 2,640 feet south and 2,000 feet few very fine and fine pores; few patchy faint dark east of the northwest corner of sec. 26, T. 3 S., reddish brown (5YR 3/4) moist; clay films on R. 13 E.; USGS Squaw Peak topographic quadrangle faces of peds and rock fragments; 25 percent (lat. 45o32'47" N.; long. 110o05'12" W.) gravel; 5 percent cobbles; moderately acid (pH 5.8). O—1 to 0 inch; partially decomposed twigs and needles; abrupt wavy boundary. Range in Characteristics A—0 to 2 inches; brown (7.5YR 5/2) loam; dark Soil temperature: 36 to 42 degrees F brown (7.5YR 3/2) moist; weak thin platy Moisture control section: Between 4 and 12 inches structure parting to weak fine granular; soft, very Depth to the Bt horizon: 5 to 20 inches friable, slightly sticky, slightly plastic; few medium Notes: Thickness of the A horizon does not exceed and coarse and common very fine and fine roots; 2 inches. Some pedons have a BC horizon. many very fine and fine pores; 10 percent gravel; slightly acid (pH 6.2); clear wavy boundary. A horizon E—2 to 9 inches; pinkish gray (7.5YR 7/2) loam, Hue: 2.5YR, 5YR, 7.5YR, 10YR, or 2.5Y brown (7.5YR 4/2) moist; weak fine and medium Value: 4 to 6 dry; 3 or 4 moist granular structure; slightly hard, friable, slightly Chroma: 2 or 3 sticky, slightly plastic; few medium and coarse Texture (less than 2 mm): Loam and common very fine and fine roots; many very Clay content: 18 to 27 percent fine and fine pores; 10 percent gravel; moderately Content of rock fragments: 0 to 35 percent—0 to acid (pH 6.0); clear wavy boundary. 15 percent stones and cobbles; 0 to 20 percent E/Bt—9 to 17 inches; E part (60 percent) pink (7.5YR gravel 7/3) loam, brown (7.5YR 5/3) moist tongues; Reaction: pH 5.6 to 7.3 Bt part (40 percent) reddish brown (5YR 5/3) clay E horizon loam, reddish brown (5YR 4/3) moist; moderate Hue: 2.5YR, 5YR, 7.5YR, 10YR, or 2.5Y fine and medium subangular blocky structure; Value: 6 or 7 dry; 3 to 5 moist moderately hard, firm, moderately sticky, Chroma: 2 or 3 moderately plastic; few fine to coarse roots; few Texture (less than 2 mm): Loam medium and many very fine and fine pores; 10 Clay content: 18 to 27 percent percent gravel; moderately acid (pH 6.0); clear Content of rock fragments: 0 to 35 percent—0 to wavy boundary. 15 percent stones and cobbles; 0 to 20 percent Bt1—17 to 28 inches; reddish brown (5YR 5/4) gravel gravelly clay loam, reddish brown (5YR 4/3) Reaction: pH 5.6 to 7.3 moist; strong fine and medium subangular blocky structure; very hard, very firm, very sticky, very E/Bt horizon plastic; few fine to coarse roots; few medium and Hue: 2.5YR, 5YR, 7.5YR, 10YR, or 2.5Y many very fine and fine pores; common Value: E part—6 or 7, Bt part—4 to 6 dry; discontinuous faint dark reddish brown (5YR 3/4) E part—4 or 5, Bt part—3 to 5 moist moist; clay films on faces of peds; 15 percent Chroma: 2 or 3 gravel; 5 percent cobbles; moderately acid (pH Texture (less than 2 mm): Loam, silt loam, clay 6.0); clear wavy boundary. loam, or silty clay loam Bt2—28 to 41 inches; reddish brown (2.5YR 5/4) Clay content: 20 to 30 percent gravelly clay loam; reddish brown (2.5YR 4/3) Content of rock fragments: 0 to 15 percent—0 to moist; moderate fine and medium subangular 3 percent cobbles; 0 to 15 percent gravel blocky structure; very hard, very firm, very sticky, Reaction: pH 5.6 to 7.3 56 Soil Survey

Bt horizons Btk—16 to 22 inches; light brownish gray (10YR 6/2) Hue: 2.5YR, 5YR, 7.5YR, 10YR, or 2.5Y clay loam, dark grayish brown (2.5Y 4/2) moist; Value: 5 to 7 dry; 4 or 5 moist moderate medium prismatic structure; moderately Chroma: 3, 4, or 6 hard, friable, moderately sticky, moderately Texture (less than 2 mm): Clay loam or clay plastic; common very fine roots; few fine pores; Clay content: 35 to 50 percent few patchy distinct dark brown (10YR 3/3) moist; Content of rock fragments: 0 to 35 percent—0 to clay films on faces of peds; many fine soft 15 percent stones and cobbles; 0 to 25 percent masses of lime; 10 percent gravel; strongly gravel effervescent; moderately alkaline (pH 8.4); clear Reaction: pH 5.6 to 7.3 smooth boundary. Bk1—22 to 31 inches; light brownish gray (10YR 6/2) clay loam, grayish brown (10YR 5/2) moist; weak Danvers Series coarse prismatic structure; moderately hard, friable, moderately sticky, moderately plastic; few Depth class: Very deep (greater than 60 inches) very fine roots; few fine pores; many fine and Drainage class: Well drained medium soft masses of lime; 10 percent gravel; Permeability: Slow (0.06 to 0.20 inch/hour) violently effervescent; strongly alkaline (pH 8.6); Landform: Fan and terrace gradual smooth boundary. Parent material: Loamy alluvium 2Bk2—31 to 60 inches; light gray (10YR 7/2) gravelly Slope range: 0 to 8 percent clay loam, grayish brown (2.5Y 5/2) moist; weak Elevation range: 4,200 to 6,200 feet coarse subangular blocky structure; moderately Mean annual precipitation: 15 to 20 inches hard, friable, slightly sticky, slightly plastic; few Mean annual air temperature: 39 to 45 degrees F very fine pores; carbonate coats on undersides Frost-free period: 70 to 115 days of rock fragments; many fine and medium soft masses of lime; 20 percent gravel; violently Taxonomic Class: Fine, smectitic, frigid Vertic effervescent; strongly alkaline (pH 8.6). Argiustolls Range in Characteristics Typical Pedon Soil temperature: 41 to 47 degrees F Moisture control section: Between 4 and 12 inches Danvers gravelly clay loam, in an area of Danvers Thickness of the mollic epipedon: 7 to 12 inches gravelly clay loam, 2 to 8 percent slopes, in an area Depth to the calcic horizon: 14 to 25 inches of hayland, 2,100 feet south and 450 feet west of the northeast corner of sec. 26, T. 4 N., R. 14 E.; USGS A horizon Melville topographic quadrangle (lat. 46o04'09" N.; Hue: 7.5YR or 10YR long. 109o56'13" W.) Value: 4 or 5 dry; 2 or 3 moist Chroma: 2 or 3 Ap—0 to 7 inches; dark grayish brown (10YR 4/2) Texture (less than 2 mm): Clay loam or loam gravelly clay loam, very dark grayish brown Clay content: 18 to 35 percent (10YR 3/2) moist; strong fine granular structure; Content of rock fragments: 0 to 35 percent—0 to moderately hard, friable, slightly sticky, slightly 15 percent stones and cobbles; 0 to 20 percent plastic; few fine and many very fine roots; gravel common very fine pores; 15 percent gravel; Reaction: pH 6.1 to 7.8 5 percent cobbles; neutral (pH 7.2); abrupt smooth boundary. Bt horizon Bt—7 to 16 inches; brown (10YR 5/3) clay, brown Hue: 7.5YR, 10YR, or 2.5Y (10YR 4/3) moist; moderate medium prismatic Value: 4 to 6 dry; 3 to 5 moist structure parting to strong fine subangular blocky; Chroma: 2 to 4 very hard, friable, moderately sticky, moderately Texture (less than 2 mm): Clay loam, clay, silty plastic; few fine and common very fine roots; few clay, or silty clay loam fine and common very fine pores; many Clay content: 35 to 50 percent discontinuous distinct dark brown (7.5YR 3/4) Content of rock fragments: 0 to 15 percent—0 to moist; clay films on faces of peds and lining 5 percent stones and cobbles; 0 to 10 percent pores; 10 percent gravel; slightly alkaline gravel (pH 7.6); clear smooth boundary. Reaction: pH 6.6 to 8.4 Sweet Grass County Area, Montana—Part I 57

Btk horizon Typical Pedon Hue: 7.5YR, 10YR, or 2.5Y Delpoint loam, in an area of Cabbart-Delpoint, Value: 5 to 7 dry; 4 to 6 moist calcareous, loams, 2 to 8 percent slopes, in an Chroma: 2 or 3 area of hayland, 400 feet south and 600 feet east Texture (less than 2 mm): Clay loam, clay, silty of the northwest corner of sec. 36, T. 3 N., R. 17 E.; clay, or silty clay loam USGS Stephens Hill NE topographic quadrangle Clay content: 35 to 45 percent (lat. 45o58'21" N.; long. 109o34'00" W.) Content of rock fragments: 0 to 15 percent—0 to 5 percent stones and cobbles; 0 to 10 percent Ap—0 to 5 inches; grayish brown (2.5Y 5/2) loam, gravel dark grayish brown (2.5Y 4/2) moist; moderate Calcium carbonate equivalent: 10 to 20 percent coarse granular structure; soft, very friable, Reaction: pH 7.4 to 8.4 slightly sticky, slightly plastic; common very fine and fine roots; many fine pores; 2 percent gravel; Bk1 horizon strongly effervescent; moderately alkaline Hue: 7.5YR, 10YR, or 2.5Y (pH 8.0); clear smooth boundary. Value: 6 to 8 dry; 5 or 6 moist Bw—5 to 11 inches; grayish brown (2.5Y 5/2) loam, Chroma: 1 to 3 dark grayish brown (2.5Y 4/2) moist; moderate Texture (less than 2 mm): Clay loam, silty clay fine subangular blocky structure; soft, very friable, loam, silty clay, or clay slightly sticky, slightly plastic; common fine and Clay content: 27 to 45 percent medium roots; common fine pores; strongly Content of rock fragments: 0 to 15 percent—0 to effervescent; moderately alkaline (pH 8.0); abrupt 5 percent cobbles; 0 to 10 percent gravel smooth boundary. Calcium carbonate equivalent: 20 to 40 percent Bk—11 to 28 inches; light gray (2.5Y 7/2) loam, light Reaction: pH 7.4 to 8.4 brownish gray (2.5Y 6/2) moist; weak fine 2Bk2 horizon subangular blocky structure; soft, very friable, Hue: 7.5YR, 10YR, or 2.5Y slightly sticky, slightly plastic; few medium roots; Value: 6 or 7 dry; 5 or 6 moist common fine pores; few soft masses of lime; Chroma: 2 or 3 violently effervescent; moderately alkaline Texture (less than 2 mm): Clay loam, loam, or (pH 8.4); clear smooth boundary. sandy loam Cr—28 to 60 inches; weakly consolidated loamy Clay content: 10 to 35 percent sedimentary beds that crush to loam; violently Content of rock fragments: 15 to 60 percent—0 to effervescent. 10 percent stones and cobbles; 15 to 50 percent gravel Range in Characteristics Calcium carbonate equivalent: 15 to 35 percent Soil temperature: 42 to 47 degrees F Reaction: pH 7.4 to 8.4 Moisture control section: Between 4 and 12 inches Depth to the Bk horizon: 10 to 20 inches Delpoint Series Depth to the Cr horizon: 20 to 40 inches Note: When mixed to 7 inches, the A horizon does Depth class: Moderately deep (20 to 40 inches) not meet the requirements of a mollic epipedon. Drainage class: Well drained A horizon Permeability: Moderate (0.6 to 2.0 inches/hour) Hue: 10YR or 2.5Y Landform: Escarpment, hill, strath terrace, stream Value: 5 or 6 dry; 3 to 5 moist terrace, knoll on plain, and swale on plain Chroma: 2 to 4 Parent material: Loamy residuum weathered from Texture (less than 2 mm): Loam sandstone and siltstone Clay content: 18 to 27 percent Slope range: 2 to 60 percent Content of rock fragments: 0 to 5 percent gravel Elevation range: 3,750 to 5,200 feet Calcium carbonate equivalent: 0 to 10 percent Mean annual precipitation: 10 to 14 inches Reaction: pH 6.6 to 8.4 Mean annual air temperature: 43 to 46 degrees F Frost-free period: 95 to 125 days Bw horizon Hue: 10YR, 2.5Y, or 5Y Taxonomic Class: Fine-loamy, mixed, superactive, Value: 5 to 7 dry; 4 or 5 moist frigid Aridic Haplustepts Chroma: 2 to 4 58 Soil Survey

Texture (less than 2 mm): Loam, clay loam, or moderately alkaline (pH 8.4); clear smooth silty clay loam boundary. Clay content: 18 to 35 percent Ag2—7 to 14 inches; gray (5Y 5/1) clay, dark olive Content of rock fragments: 0 to 15 percent gravel gray (5Y 3/2) moist; few fine distinct olive brown Reaction: pH 6.6 to 8.4 (2.5Y 4/4) and dark yellowish brown (10YR 4/6) moist, redox concentrations; strong fine and Bk horizon medium subangular blocky structure; extremely Hue: 10YR, 2.5Y, or 5Y hard, very firm, very sticky, very plastic; few very Value: 5 to 7 dry; 4 to 6 moist fine and fine roots; few very fine pores; slightly Chroma: 2 to 4 effervescent; moderately alkaline (pH 8.4); clear Texture (less than 2 mm): Loam, clay loam, or smooth boundary. sandy loam Bkg1—14 to 34 inches; gray (5Y 5/1) clay, dark gray Clay content: 18 to 35 percent (5Y 4/1) moist; moderate medium subangular Content of rock fragments: 0 to 15 percent gravel blocky structure; very hard, firm, very sticky, very Calcium carbonate equivalent: 5 to 15 percent plastic; few very fine and fine roots; few very fine Reaction: pH 7.9 to 9.0 pores; common fine and medium soft masses of lime; strongly effervescent; moderately alkaline Dimmick Series (pH 8.6); gradual smooth boundary. Bkg2—34 to 60 inches; grayish brown (2.5Y 5/2) clay, Depth class: Very deep (greater than 60 inches) dark gray (5Y 4/1) moist; common fine distinct Drainage class: Very poorly drained olive brown (2.5Y 4/4) and dark yellowish brown Permeability: Very slow (less than 0.06 inch/hour) (10YR 4/6) moist, redox concentrations; Landform: Depression on plain and swale on plain moderate coarse prismatic structure; very hard, Parent material: Clayey alluvium firm, very sticky, very plastic; few fine soft masses Slope range: 0 to 2 percent of lime; strongly effervescent; strongly alkaline Elevation range: 3,750 to 5,600 feet (pH 8.8). Mean annual precipitation: 10 to 19 inches Mean annual air temperature: 43 to 46 degrees F Range in Characteristics Frost-free period: 95 to 125 days Soil temperature: 41 to 47 degrees F Moisture control section: Between 4 and 12 inches Taxonomic Class: Fine, smectitic, frigid Vertic Thickness of the mollic epipedon: 14 to 20 inches Epiaquolls Depth to the seasonal high water table: +12 to 6 inches; perched Typical Pedon Depth to the Bkg horizon: 10 to 24 inches Dimmick silty clay, in an area of Dimmick silty clay, A horizons 0 to 2 percent slopes, in an area of rangeland, Hue: 10YR, 2.5Y, or 5Y 1,100 feet north and 1,200 feet west of the southeast Value: 4 or 5 dry; 2 or 3 moist corner of sec. 27, T. 4 N., R. 16 E.; USGS Gibson Chroma: 1 or 2 SW topographic quadrangle (lat. 46o03'45" N.; long. Redox concentrations: Few to many; chroma of 109o42'46" W.) 4 or 6 Redox depletions: None to common; chroma of A—0 to 2 inches; dark gray (5Y 4/1) silty clay, very 0 or 1 dark grayish brown (2.5Y 3/2) moist; moderate Texture (less than 2 mm): Silty clay medium granular structure; moderately hard, firm, Clay content: 40 to 50 percent very sticky, very plastic; many very fine and fine Content of rock fragments: 0 to 15 percent gravel roots; many very fine and fine pores; moderately Reaction: pH 6.1 to 7.8 alkaline (pH 8.4); clear smooth boundary. Ag1—2 to 7 inches; dark gray (5Y 4/1) clay, dark olive Bkg horizons gray (5Y 3/2) moist; common fine distinct olive Hue: 2.5Y, 5Y, or N brown (2.5Y 4/4) and dark yellowish brown (10YR Value: 5 to 7 dry; 4 to 6 moist 4/6) moist, redox concentrations; strong fine and Chroma: 0 to 2 medium subangular blocky structure; very hard, Redox concentrations: None to common; chroma very firm, very sticky, very plastic; common very of 4 or 6 fine and fine roots; few very fine and fine pores; Texture (less than 2 mm): Clay or silty clay Sweet Grass County Area, Montana—Part I 59

Clay content: 40 to 60 percent Cr—19 to 60 inches; gray (10YR 5/1) dark gray Content of rock fragments: 0 to 5 percent gravel semiconsolidated shale (10YR 4/1) moist; few Calcium carbonate equivalent: 3 to 15 percent very fine and fine roots between shale fragments; Reaction: pH 6.6 to 8.4 strongly effervescent; moderately alkaline; common irregular carbonate coats on undersides of shale fragments. Doby Series Range in Characteristics Depth class: Shallow (10 to 20 inches) Drainage class: Well drained Soil temperature: 36 to 45 degrees F Permeability: Slow (0.06 to 0.20 inch/hour) Moisture control section: Between 4 and 12 inches Landform: Mountain Depth to the Cr horizon: 10 to 20 inches Parent material: Clayey residuum weathered from shale and siltstone A horizon Slope range: 15 to 60 percent Hue: 10YR or 2.5Y Elevation range: 5,500 to 7,500 feet Value: 4 or 5 dry; 2 or 3 moist Mean annual precipitation: 20 to 25 inches Chroma: 1 or 2 Mean annual air temperature: 36 to 38 degrees F Texture (less than 2 mm): Clay loam Frost-free period: 50 to 70 days Clay content: 30 to 40 percent Content of rock fragments: 0 to 25 percent—0 to Taxonomic Class: Clayey, smectitic, shallow Ustic 10 percent stones and cobbles; 0 to 15 percent Haplocryolls gravel or channers Reaction: pH 6.6 to 7.8 Typical Pedon Bw horizons Doby clay loam, in an area of Bangtail-Doby- Hue: 10YR or 2.5Y Redlodge complex, 4 to 45 percent slopes, in an Value: 4 to 6 dry; 3 or 4 moist area of rangeland, 300 feet north and 1,300 feet Chroma: 1 to 4 east of the southwest corner of sec. 2, T. 4 N., R. 7 E.; Texture (less than 2 mm): Clay or silty clay Gallatin County, Montana. Clay content: 40 to 55 percent A—0 to 5 inches; gray (10YR 5/1) clay loam, very Content of rock fragments: 0 to 25 percent gravel dark gray (10YR 3/1) moist; moderate fine and or channers; 0 to 50 percent soft shale chips medium granular structure; soft, friable, Reaction: pH 6.6 to 7.8 moderately sticky, moderately plastic; many very fine and fine roots; many very fine and fine vesicular pores; 5 percent channers; neutral; Doney Series abrupt smooth boundary. Bw1—5 to 10 inches; grayish brown (2.5Y 5/2) clay, Depth class: Moderately deep (20 to 40 inches) dark gray (10YR 4/1) moist; moderate medium Drainage class: Well drained subangular blocky structure; hard, firm, very Permeability: Moderate (0.6 to 2.0 inches/hour) sticky, very plastic; many very fine and fine roots; Landform: Escarpment, hill, and swale on plain few very fine tubular pores; 5 percent channers; Parent material: Loamy residuum weathered from neutral; clear smooth boundary. sandstone and siltstone Bw2—10 to 15 inches; grayish brown (2.5Y 5/2) clay, Slope range: 2 to 60 percent dark grayish brown (10YR 4/1) moist; moderate Elevation range: 3,900 to 6,200 feet medium prismatic structure parting to moderate Mean annual precipitation: 15 to 20 inches medium subangular blocky; hard, firm, very Mean annual air temperature: 39 to 45 degrees F sticky, very plastic; few fine and medium roots; Frost-free period: 70 to 115 days few very fine vesicular pores; 10 percent channers; neutral; clear smooth boundary. Taxonomic Class: Fine-loamy, mixed, superactive, C—15 to 19 inches; light brownish gray (2.5Y 6/2) frigid Typic Haplustepts channery clay, dark gray (10YR 4/1) moist; Typical Pedon weak coarse prismatic structure; hard, firm, very sticky, very plastic; few fine and medium Doney loam, in an area of Doney-Cabba loams, 2 to roots; 20 percent soft shale fragments; neutral; 8 percent slopes, in an area of rangeland, 1,300 feet clear smooth boundary. north and 200 feet east of the southwest corner of 60 Soil Survey

sec. 24, T. 4 N., R. 14 E.; USGS Melville topographic Bw horizon quadrangle (lat. 46o04'41" N.; long. 109o56'08" W.) Hue: 10YR or 2.5Y Value: 5 to 7 dry; 4 to 6 moist A—0 to 5 inches; grayish brown (2.5Y 5/2) loam, dark Chroma: 2 to 4 grayish brown (2.5Y 4/2) moist; weak fine Texture (less than 2 mm): Loam or clay loam granular structure; soft, very friable, slightly sticky, Clay content: 18 to 30 percent slightly plastic; many very fine and fine roots; Content of rock fragments: 0 to 35 percent—0 to many very fine and fine pores; slightly 10 percent cobbles; 0 to 25 percent gravel effervescent; slightly alkaline (pH 7.6); clear Calcium carbonate equivalent: 5 to 15 percent smooth boundary. Reaction: pH 7.9 to 9.0 Bw—5 to 11 inches; light brownish gray (2.5Y 6/2) loam, grayish brown (2.5Y 5/2) moist; weak Bk horizons medium prismatic structure parting to moderate Hue: 2.5Y or 10YR medium subangular blocky; soft, very friable, Value: 6 to 8 dry; 5 to 7 moist slightly sticky, slightly plastic; many very fine Chroma: 2 to 4 and fine roots; common very fine and fine pores; Texture (less than 2 mm): Loam, clay loam, or 5 percent gravel; strongly effervescent; silty clay loam moderately alkaline (pH 8.0); abrupt smooth Clay content: 18 to 30 percent boundary. Content of rock fragments: 0 to 30 percent—0 to Bk1—11 to 18 inches; light brownish gray (2.5Y 6/2) 10 percent cobbles; 0 to 20 percent gravel loam, grayish brown (2.5Y 5/2) moist; moderate Calcium carbonate equivalent: 5 to 15 percent coarse subangular blocky structure; soft, very Reaction: pH 7.9 to 9.0 friable, slightly sticky, nonplastic; few fine and common very fine roots; common fine pores; common fine threads and soft masses of lime; Duckcreek Series 10 percent gravel; strongly effervescent; Depth class: Moderately deep (20 to 40 inches) moderately alkaline (pH 8.4); clear smooth Drainage class: Well drained boundary. Permeability: Slow (0.06 to 0.20 inch/hour) Bk2—18 to 33 inches; light gray (10YR 7/2) loam, Landform: Mountain light brownish gray (2.5Y 6/2) moist; weak coarse Parent material: Clayey residuum weathered from subangular blocky structure; soft, very friable, sandstone and shale slightly sticky, nonplastic; few very fine roots; few Slope range: 8 to 45 percent fine pores; 10 percent gravel; common medium Elevation range: 6,000 to 7,500 feet soft masses of lime; violently effervescent; Mean annual precipitation: 20 to 25 inches strongly alkaline (pH 8.6); gradual smooth Mean annual air temperature: 36 to 38 degrees F boundary. Frost-free period: 50 to 70 days Cr—33 to 60 inches; weakly consolidated loamy sedimentary beds that crush to loam; violently Taxonomic Class: Fine, mixed, superactive Ustic effervescent. Argicryolls Range in Characteristics Typical Pedon Soil temperature: 41 to 47 degrees F Duckcreek loam, in an area of Duckcreek-Arrowpeak Moisture control section: Between 4 and 12 inches complex, 8 to 45 percent slopes, in an area of Depth to the Bk horizon: 11 to 20 inches rangeland, 2,400 feet south and 200 feet east of Depth to the Cr horizon: 20 to 40 inches the northwest corner of sec. 19, T. 2 N., R. 12 E.; USGS Fairview Peak topographic quadrangle A horizon (lat. 45o54'31" N.; long. 110o17'28" W.) Hue: 10YR or 2.5Y Value: 5 or 6 dry; 4 or 5 moist A—0 to 6 inches; brown (10YR 4/3) loam, dark brown Chroma: 2 or 3 (10YR 3/3) moist; weak fine granular structure; Texture (less than 2 mm): Loam soft, very friable, slightly sticky, slightly plastic; Clay content: 10 to 27 percent few fine and medium and many very fine roots; Content of rock fragments: 0 to 35 percent—0 to many very fine and fine pores; 5 percent gravel; 10 percent cobbles; 0 to 25 percent gravel 5 percent stones; neutral (pH 7.2); clear smooth Reaction: pH 6.6 to 8.4 boundary. Sweet Grass County Area, Montana—Part I 61

Bt1—6 to 15 inches; dark yellowish brown (10YR 4/4) Clay content: 35 to 50 percent clay loam, dark brown (10YR 3/3) moist; weak Content of rock fragments: 0 to 25 percent—0 to medium subangular blocky structure parting to 5 percent cobbles; 0 to 15 percent gravel or strong fine granular; moderately hard, friable, channers; 0 to 20 percent soft shale chips moderately sticky, moderately plastic; few fine Reaction: pH 6.1 to 7.3 and medium and common very fine roots; Bt2 horizon common very fine pores; common faint Hue: 10YR or 2.5Y discontinuous dark yellowish brown (10YR 3/4) Value: 5 or 6 dry; 4 or 5 moist moist; clay films on faces of peds; 10 percent Chroma: 2 to 4 gravel; neutral (pH 7.2); clear smooth boundary. Texture (less than 2 mm): Clay loam or clay Bt2—15 to 29 inches; light yellowish brown (10YR Clay content: 35 to 50 percent 6/4) gravelly clay loam, brown (10YR 5/3) moist; Content of rock fragments: 0 to 35 percent—0 to weak medium subangular blocky structure 5 percent cobbles; 0 to 30 percent gravel or parting to moderate fine granular; moderately channers; 0 to 20 percent soft shale chips hard, friable, moderately sticky, moderately Reaction: pH 6.1 to 7.8 plastic; few very fine and fine roots; common very fine pores; common faint discontinuous dark Bk horizon yellowish brown (10YR 4/4) moist; clay films on Hue: 10YR to 2.5Y faces of peds; 20 percent gravel; slightly alkaline Value: 5 to 7 dry; 4 to 6 moist (pH 7.4); clear smooth boundary. Chroma: 2 to 4 Bk—29 to 36 inches; light gray (2.5Y 7/2) sandy clay Texture (less than 2 mm): Loam, sandy clay loam, loam, grayish brown (2.5Y 5/2) moist; weak clay loam, or clay coarse prismatic structure; soft, very friable, Clay content: 27 to 45 percent slightly sticky, slightly plastic; few very fine and Content of rock fragments: 0 to 35 percent—0 to fine roots; common very fine pores; common fine 5 percent cobbles; 0 to 30 percent gravel or soft masses of lime; 30 percent soft shale channers; 10 to 35 percent soft shale chips fragments; strongly effervescent; moderately Calcium carbonate equivalent: 5 to 15 percent alkaline (pH 8.2); clear wavy boundary. Reaction: pH 7.4 to 8.4 Cr—36 to 60 inches; moderately hard black shale that can be hand augered; strongly effervescent. Range in Characteristics Elve Series Soil temperature: 36 to 40 degrees F Depth class: Very deep (greater than 60 inches) Moisture control section: Between 4 and 12 inches Drainage class: Somewhat excessively drained Thickness of the mollic epipedon: 8 to 15 inches Permeability: Moderately rapid (2 to 6 inches/hour) Depth to the Bk horizon: 15 to 35 inches Landform: Mountain Depth to the Cr horizon: 20 to 40 inches Parent material: Loamy alluvium weathered from volcanic breccia A horizon Slope range: 25 to 80 percent Hue: 10YR or 2.5Y Elevation range: 5,500 to 7,500 feet Value: 3 to 5 dry; 2 or 3 moist Mean annual precipitation: 20 to 25 inches Chroma: 1 to 3 Mean annual air temperature: 36 to 38 degrees F Texture (less than 2 mm): Loam Frost-free period: 50 to 70 days Clay content: 10 to 27 percent Content of rock fragments: 0 to 25 percent—0 to Taxonomic Class: Loamy-skeletal, mixed, 5 percent stones and flagstones; 0 to 5 percent superactive Ustic Eutrocryepts cobbles; 0 to 15 percent gravel or channers; 0 to 20 percent soft shale chips Typical Pedon Reaction: pH 5.6 to 7.3 Elve very gravelly loam, in an area of Merino-Elve- Bt1 horizon Rock outcrop complex, 25 to 80 percent slopes, Hue: 10YR or 2.5Y in an area of coniferous forest, 700 feet north and Value: 4 to 6 dry; 3 to 5 moist 1,100 feet west of the southeast corner of sec. 13, Chroma: 2 to 4 T. 3 S., R. 13 E.; USGS Squaw Peak topographic Texture (less than 2 mm): Clay loam or clay quadrangle (lat. 45o34'13" N.; long. 110o03'26" W.) 62 Soil Survey

Oi—0 to 1 inch; slightly decayed needles, twigs, and BC horizon leaves; moderately acid (pH 6.0); abrupt smooth Hue: 7.5YR, 10YR, or 2.5Y boundary. Value: 5 to 7 dry; 4 or 5 moist E—0 to 6 inches; grayish brown (2.5Y 6/2) very Chroma: 2 or 3 gravelly loam, dark grayish brown (2.5Y 4/2) Texture (less than 2 mm): Sandy loam or fine moist; weak fine granular structure; soft, very sandy loam friable, nonsticky, nonplastic; few coarse and Clay content: 10 to 20 percent common very fine to medium roots; many very Content of rock fragments: 60 to 85 percent— fine and fine pores; 40 percent gravel; neutral 10 to 25 percent cobbles; 50 to 60 percent (pH 6.8); abrupt wavy boundary. gravel Bw1—6 to 17 inches; light brownish gray (2.5Y 6/2) Reaction: pH 5.1 to 6.6 extremely gravelly sandy loam, dark grayish brown (2.5Y 4/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky, Ethridge Series nonplastic; few fine to coarse and common very Depth class: Very deep (greater than 60 inches) fine roots; many very fine and fine pores; 60 Drainage class: Well drained percent gravel; neutral (pH 6.8); clear wavy Permeability: Slow (0.06 to 0.20 inch/hour) boundary. Landform: Fan, hill, stream terrace, terrace, Bw2—17 to 30 inches; light brownish gray (2.5Y 6/2) drainageway on escarpment, swale on extremely gravelly sandy loam, dark grayish escarpment, drainageway on fan, swale on fan, brown (2.5Y 4/2) moist; weak fine subangular drainageway on plain, and swale on plain blocky structure; soft, very friable, nonsticky, Parent material: Clayey alluvium nonplastic; few very fine to coarse roots; many Slope range: 1 to 35 percent very fine pores; 60 percent gravel; neutral Elevation range: 3,750 to 5,200 feet (pH 6.8); clear wavy boundary. Mean annual precipitation: 10 to 14 inches BC—30 to 60 inches; light brownish gray (2.5Y 6/2) Mean annual air temperature: 43 to 46 degrees F extremely gravelly sandy loam, dark grayish Frost-free period: 95 to 125 days brown (2.5Y 4/2) moist; massive; soft, very friable, nonsticky, nonplastic; 10 percent cobbles; Taxonomic Class: Fine, smectitic, frigid Torrertic 60 percent gravel; neutral (pH 6.6). Argiustolls Range in Characteristics Typical Pedon Soil temperature: 42 to 45 degrees F Moisture control section: Between 4 and 12 inches Ethridge clay loam, in an area of Ethridge clay Note: Some pedons have an A horizon. loam, 4 to 8 percent slopes, in an area of rangeland, E horizon 1,200 feet south and 1,700 feet west of the northeast Hue: 10YR or 2.5Y corner of sec. 27, T. 4 N., R. 16 E.; USGS Gibson SW Value: 5 or 6 dry; 3 or 4 moist topographic quadrangle (lat. 46o04'16" N.; long. Chroma: 2 or 3 109o42'54" W.) Texture (less than 2 mm): Loam A—0 to 4 inches; brown (10YR 4/3) clay loam, dark Clay content: 10 to 20 percent brown (10YR 3/3) moist; weak fine granular Content of rock fragments: 15 to 60 percent—0 to structure; soft, very friable, moderately sticky, 5 percent cobbles; 15 to 55 percent gravel moderately plastic; common very fine and fine Reaction: pH 5.1 to 7.3 roots; many very fine and fine pores; neutral Bw horizons (pH 6.6); clear smooth boundary. Hue: 10YR or 2.5Y Bt1—4 to 8 inches; brown (10YR 5/3) clay loam, dark Value: 6 dry; 4 or 5 moist brown (10YR 3/3) moist; weak medium Chroma: 2 to 4 subangular blocky structure parting to moderate Texture (less than 2 mm): Sandy loam or loam medium granular; slightly hard, friable, Clay content: 10 to 20 percent moderately sticky, moderately plastic; common Content of rock fragments: 60 to 80 percent—0 to very fine and fine roots; many very fine and fine 20 percent cobbles; 25 to 60 percent gravel pores; common distinct discontinuous brown Reaction: pH 5.1 to 7.3 (7.5YR 4/3) moist; clay films on faces of peds and Sweet Grass County Area, Montana—Part I 63

lining pores; neutral (pH 6.8); clear smooth Chroma: 2 to 4 boundary. Texture (less than 2 mm): Clay, clay loam, or silty Bt2—8 to 16 inches; brown (10YR 5/3) clay, brown clay (10YR 4/3) moist; strong medium and coarse Clay content: 35 to 45 percent subangular blocky structure; very hard, firm, very Content of rock fragments: 0 to 5 percent gravel sticky, very plastic; common very fine and fine Reaction: pH 6.6 to 8.4 roots; common very fine pores; many prominent Bk horizon continuous strong brown (7.5YR 4/6) moist; clay Hue: 10YR or 2.5Y films on faces of peds and lining pores; neutral Value: 5 to 7 dry; 4 to 6 moist (pH 7.0); gradual smooth boundary. Chroma: 2 to 4 Bt3—16 to 23 inches; grayish brown (10YR 5/2) clay, Texture (less than 2 mm): Clay, clay loam, or silty dark grayish brown (10YR 4/2) moist; moderate clay coarse prismatic structure; very hard, firm, very Clay content: 30 to 45 percent sticky, very plastic; few very fine and fine roots; Content of rock fragments: 0 to 5 percent gravel common very fine pores; common faint patchy Calcium carbonate equivalent: 5 to 15 percent brown (10YR 5/3) moist; clay films on faces Sodium adsorption ratio: 1 to 5 of peds; slightly effervescent; slightly alkaline Reaction: pH 7.4 to 9.0 (pH 7.4); abrupt smooth boundary. Bk—23 to 42 inches; light brownish gray (10YR 6/2) Bky horizon clay, grayish brown (10YR 5/2) moist; moderate Hue: 10YR or 2.5Y coarse prismatic structure; very hard, firm, Value: 5 to 7 dry; 4 to 6 moist moderately sticky, moderately plastic; few very Chroma: 2 to 4 fine roots; few very fine pores; common medium Texture (less than 2 mm): Clay loam, loam, silt soft masses of lime; strongly effervescent; loam, or silty clay loam moderately alkaline (pH 8.2); clear smooth Clay content: 25 to 40 percent boundary. Content of rock fragments: 0 to 5 percent gravel Bky—42 to 60 inches; light brownish gray (10YR 6/2) Calcium carbonate equivalent: 5 to 15 percent clay loam; grayish brown (10YR 5/2) moist; weak Electrical conductivity: 2 to 4 mmhos/cm coarse prismatic structure; very hard, firm, Sodium adsorption ratio: 1 to 5 moderately sticky, moderately plastic; few very Gypsum content: 1 to 3 percent fine roots; few very fine pores; common fine soft Reaction: pH 7.4 to 9.0 masses and threads of lime; few very fine and fine plates of gypsum; strongly effervescent; moderately alkaline (pH 8.2). Evanston Series Depth class: Very deep (greater than 60 inches) Range in Characteristics Drainage class: Well drained Soil temperature: 42 to 47 degrees F Permeability: Moderate (0.6 to 2.0 inches/hour) Moisture control section: Between 4 and 12 inches Landform: Fan, hill, stream terrace, terrace, and Thickness of the mollic epipedon: 7 to 14 inches swale on plain Depth to the Bk horizon: 10 to 24 inches Parent material: Loamy alluvium Note: Some pedons have a Btk horizon and a Slope range: 0 to 35 percent BC horizon, which consists of stratified materials. Elevation range: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches A horizon Mean annual air temperature: 43 to 46 degrees F Hue: 10YR or 2.5Y Frost-free period: 95 to 125 days Value: 4 or 5 dry; 2 or 3 moist Chroma: 2 or 3 Taxonomic Class: Fine-loamy, mixed, superactive, Texture (less than 2 mm): Clay loam or loam frigid Aridic Argiustolls Clay content: 20 to 35 percent Content of rock fragments: 0 to 5 percent gravel Typical Pedon Reaction: pH 6.1 to 8.4 Evanston loam, in an area of Evanston-Reedpoint Bt horizons complex, 8 to 35 percent slopes, in an area of Hue: 10YR or 2.5Y rangeland, 1,350 feet south and 300 feet east of the Value: 4 or 5 dry; 3 or 4 moist northwest corner of sec. 22, T. 1 S., R. 17 E.; USGS 64 Soil Survey

Reed Point topographic quadrangle (lat. 45o44'11" N.; Content of rock fragments: 0 to 15 percent gravel long. 109o37'24" W.) Reaction: pH 6.6 to 7.8 A—0 to 4 inches; grayish brown (10YR 5/2) loam, Bt horizons dark brown (10YR 3/3) moist; moderate fine Hue: 7.5YR, 10YR, or 2.5Y subangular blocky structure parting to moderate Value: 4 to 6 dry; 3 to 5 moist medium granular; soft, very friable, slightly sticky, Chroma: 2 to 4 slightly plastic; many very fine and fine roots; Texture (less than 2 mm): Loam, clay loam, or many very fine and fine pores; neutral (pH 7.3); sandy clay loam abrupt smooth boundary. Clay content: 20 to 35 percent Bt1—4 to 10 inches; grayish brown (10YR 5/2) loam, Content of rock fragments: 0 to 15 percent gravel dark brown (10YR 3/3) moist; moderate medium Reaction: pH 6.6 to 7.8 subangular blocky structure; slightly hard, very Bk horizons friable, slightly sticky, slightly plastic; many Hue: 7.5YR, 10YR, or 2.5Y distinct discontinuous brown (7.5YR 4/4) moist; Value: 5 to 7 dry; 4 to 6 moist clay films on faces of peds and lining pores; Chroma: 2 to 4 slightly alkaline (pH 7.6); clear smooth boundary. Texture (less than 2 mm): Loam, very fine sandy Bt2—10 to 16 inches; brown (10YR 5/3) loam, dark loam, clay loam, or sandy loam grayish brown (10YR 4/2) moist; moderate fine Clay content: 15 to 30 percent and medium subangular blocky structure; slightly Content of rock fragments: 0 to 15 percent gravel hard, very friable, slightly sticky, slightly plastic; Calcium carbonate equivalent: 5 to 15 percent common fine roots; common very fine and fine Reaction: pH 7.4 to 9.0 pores; few distinct discontinuous brown (7.5YR 4/4) moist; clay films on faces of peds and lining pores; slightly alkaline (pH 7.6); clear smooth Fairfield Series boundary. Bk1—16 to 31 inches; light brownish gray (10YR 6/2) Depth class: Very deep (greater than 60 inches) loam, grayish brown (10YR 5/2) moist; weak Drainage class: Well drained coarse prismatic structure; soft, very friable, Permeability: Moderately slow (0.2 to 0.6 inch/hour) slightly sticky, slightly plastic; few fine roots; Landform: Fan, moraine, and terrace common very fine and fine pores; common fine Parent material: Loamy alluvium soft masses of lime; strongly effervescent; Slope range: 2 to 35 percent moderately alkaline (pH 8.4); clear smooth Elevation range: 4,200 to 6,200 feet boundary. Mean annual precipitation: 15 to 20 inches Bk2—31 to 60 inches; light brownish gray (2.5Y 6/2) Mean annual air temperature: 39 to 45 degrees F very fine sandy loam, grayish brown (2.5Y 5/2) Frost-free period: 85 to 115 days moist; weak coarse prismatic structure; soft, very friable, nonsticky, nonplastic; common fine soft Taxonomic Class: Fine-loamy, mixed, superactive, masses of lime; strongly effervescent; moderately frigid Typic Argiustolls alkaline (pH 8.4). Typical Pedon Range in Characteristics Fairfield gravelly loam, in an area of Fairfield gravelly loam, 2 to 8 percent slopes, in an area of rangeland, Soil temperature: 44 to 46 degrees F 2,400 feet south and 1,300 feet west of the northeast Moisture control section: Between 4 and 12 inches corner of sec. 19, T. 1 S., R. 13 E.; USGS Springdale Thickness of the mollic epipedon: 7 to 15 inches topographic quadrangle (lat. 45o44'06" N.; long. Depth to the Bk horizon: 10 to 20 inches 110o09'46" W.) Note: Some pedons have a Btk horizon. A—0 to 4 inches; dark grayish brown (10YR 4/2) A horizon gravelly loam, very dark grayish brown (10YR Hue: 7.5YR, 10YR, or 2.5Y 3/2) moist; weak fine granular structure; soft, very Value: 5 dry; 2 or 3 moist friable, slightly sticky, slightly plastic; many very Chroma: 2 or 3 fine and fine roots; many very fine and fine pores; Texture (less than 2 mm): Loam 20 percent gravel; neutral (pH 6.8); clear smooth Clay content: 20 to 27 percent boundary. Sweet Grass County Area, Montana—Part I 65

Bt—4 to 7 inches; brown (10YR 4/3) clay loam, dark A horizon brown (10YR 3/3) moist; moderate medium and Hue: 7.5YR or 10YR coarse subangular blocky structure; slightly hard, Value: 3 or 4 dry; 2 or 3 moist friable, moderately sticky, moderately plastic; Chroma: 2 or 3 many very fine and fine roots; many very fine and Texture (less than 2 mm): Loam fine pores; common faint discontinuous dark Clay content: 18 to 27 percent yellowish brown (10YR 3/4) moist; clay films on Content of rock fragments: 0 to 35 percent—0 to faces of peds and lining pores; 5 percent gravel; 15 percent stones and cobbles; 0 to 20 percent neutral (pH 7.0); abrupt smooth boundary. gravel Btk—7 to 9 inches; brown (10YR 5/3) loam, dark Reaction: pH 6.6 to 7.8 brown (10YR 4/3) moist; moderate medium and Bt horizon coarse subangular blocky structure; slightly hard, Hue: 7.5YR, 10YR, or 2.5Y friable, moderately sticky, moderately plastic; Value: 4 or 5 dry; 3 or 4 moist many very fine and fine roots; many very fine and Chroma: 2 or 3 fine pores; common faint discontinuous dark Texture (less than 2 mm): Loam or clay loam yellowish brown (10YR 3/4) moist; clay films on Clay content: 25 to 35 percent faces of peds and lining pores; few fine threads of Content of rock fragments: 0 to 35 percent—0 to lime; 5 percent gravel; slightly effervescent; 10 percent cobbles; 0 to 25 percent gravel slightly alkaline (pH 7.4); abrupt smooth Reaction: pH 6.6 to 8.4 boundary. Bk1—9 to 22 inches; light gray (10YR 7/2) loam, Btk horizon: grayish brown (10YR 5/2) moist; weak medium Hue: 7.5YR, 10YR, or 2.5Y and coarse prismatic structure; soft, very friable, Value: 4 or 5 dry; 3 or 4 moist slightly sticky, slightly plastic; many very fine and Chroma: 2 or 3 fine roots; many very fine and fine pores; Texture (less than 2 mm): Loam or clay loam common fine and medium masses of lime; Clay content: 25 to 35 percent 5 percent gravel; violently effervescent; Content of rock fragments: 0 to 35 percent—0 to moderately alkaline (pH 8.2); clear smooth 10 percent cobbles; 0 to 25 percent gravel boundary. Calcium carbonate equivalent: 5 to 15 percent Bk2—22 to 36 inches; light gray (10YR 7/2) loam, Reaction: pH 6.6 to 8.4 pale brown (10YR 6/3) moist; weak coarse Bk1 horizon prismatic structure; soft, very friable, slightly Hue: 7.5YR, 10YR, or 2.5Y sticky, nonplastic; common very fine and fine Value: 6 to 8 dry; 5 to 7 moist roots; many very fine and fine pores; common Chroma: 2 or 3 carbonate coats on rock fragments; common fine Texture (less than 2 mm): Loam, clay loam, or soft masses of lime; 10 percent gravel; violently silty clay loam effervescent; moderately alkaline (pH 8.4); Clay content: 25 to 35 percent gradual smooth boundary. Content of rock fragments: 0 to 35 percent—0 to Bk3—36 to 60 inches; light gray (10YR 7/2) gravelly 10 percent cobbles; 0 to 25 percent gravel very fine sandy loam, light brownish gray (10YR Calcium carbonate equivalent: 15 to 35 percent 6/2) moist; weak coarse prismatic structure; soft, Reaction: pH 7.9 to 8.4 very friable, nonsticky, nonplastic; few fine roots; many very fine and fine pores; common Bk2 horizon carbonate coats on rock fragments; 20 percent Hue: 7.5YR, 10YR, or 2.5Y gravel; 5 percent cobbles; strongly effervescent; Value: 6 to 8 dry; 5 to 7 moist moderately alkaline (pH 8.4). Chroma: 2 to 4 Texture (less than 2 mm): Loam, clay loam, or Range in Characteristics silty clay loam Soil temperature: 42 to 47 degrees F Clay content: 25 to 35 percent Moisture control section: Between 4 and 12 inches Content of rock fragments: 0 to 35 percent—0 to Thickness of the mollic epipedon: 7 to 10 inches 15 percent cobbles; 0 to 20 percent gravel Depth to the calcic horizon: 7 to 10 inches Calcium carbonate equivalent: 10 to 30 percent Note: Some pedons do not have a Btk horizon. Reaction: pH 7.9 to 9.0 66 Soil Survey

Bk3 horizon moderate medium prismatic structure parting to Hue: 7.5YR, 10YR, or 2.5Y moderate medium angular blocky; moderately Value: 6 to 8 dry; 5 to 7 moist hard, friable, moderately sticky, moderately Chroma: 2 to 4 plastic; few medium and coarse and common Texture (less than 2 mm): Very fine sandy loam, very fine and fine roots; common fine soft masses loam, clay loam, or silty clay loam of lime; strongly effervescent; moderately alkaline Clay content: 18 to 35 percent (pH 8.4); clear wavy boundary. Content of rock fragments: 0 to 35 percent—0 to Bk2—18 to 25 inches; light brownish gray (2.5Y 6/2) 15 percent cobbles; 0 to 20 percent gravel clay loam, dark grayish brown (2.5Y 4/2) moist; Calcium carbonate equivalent: 10 to 30 percent few fine faint olive brown (2.5Y 4/4) moist, redox Reaction: pH 7.9 to 9.0 concentrations; weak coarse subangular blocky structure; moderately hard, friable, moderately sticky, moderately plastic; few fine and common Fairway Series very fine roots; common very fine and fine pores; common fine soft masses of lime; strongly Depth class: Very deep (greater than 60 inches) effervescent; moderately alkaline (pH 8.4); clear Drainage class: Somewhat poorly drained wavy boundary. Permeability: Moderate (0.6 to 2.0 inches/hour) Bg—25 to 44 inches; light brownish gray (2.5Y 6/2) Landform: Flood plain, flood-plain step, and stream loam, dark grayish brown (2.5Y 4/2) moist; terrace common medium prominent strong brown (7.5YR Parent material: Loamy alluvium 4/6) moist, redox concentrations; massive; slightly Slope range: 0 to 4 percent hard, very friable, slightly sticky, slightly plastic; Elevation range: 3,750 to 6,200 feet few very fine and fine roots; few thin strata of Mean annual precipitation: 10 to 20 inches coarser textured material; strongly effervescent; Mean annual air temperature: 39 to 46 degrees F moderately alkaline (pH 8.0); clear smooth Frost-free period: 70 to 130 days boundary. 2Cg—44 to 60 inches; gray (10YR 6/1) sandy loam, Taxonomic Class: Fine-loamy, mixed, superactive, dark gray (10YR 4/1) moist; common medium frigid Fluvaquentic Haplustolls prominent strong brown (7.5YR 4/6) moist, redox Typical Pedon concentrations; few fine faint dark greenish gray (5BG 4/1) moist, redox depletions; massive; soft, Fairway loam, in an area of Fairway loam, 0 to very friable, slightly sticky, nonplastic; thin strata 2 percent slopes, in an area of hayland, 1,800 feet of gravelly loamy sand and very fine sandy south and 2,150 feet east of the northwest corner loam; few very fine and fine roots; 5 percent of sec. 34, T. 1 N., R. 12 E.; USGS Kelly Hills gravel; slightly effervescent; moderately alkaline topographic quadrangle (lat. 45o47'41" N.; long. (pH 8.0). 110o13'12" W.) Ap—0 to 5 inches; grayish brown (2.5Y 5/2) loam, Range in Characteristics very dark grayish brown (2.5Y 3/2) moist; weak Soil temperature: 42 to 47 degrees F medium granular structure; slightly hard, friable, Moisture control section: Between 4 and 12 inches slightly sticky, slightly plastic; few medium and Thickness of the mollic epipedon: 10 to 15 inches common very fine and fine roots; common very Depth to the seasonal high water table: 24 to fine and fine pores; slightly effervescent; slightly 42 inches alkaline (pH 7.6); clear smooth boundary. Depth to the 2Cg horizon: Greater than 40 inches A2—5 to 10 inches; grayish brown (2.5Y 5/2) loam, very dark grayish brown (2.5Y 3/2) moist; A or Ap horizon moderate medium subangular blocky structure; Hue: 10YR or 2.5Y slightly hard, friable, slightly sticky, slightly plastic; Value: 4 or 5 dry; 2 or 3 moist few fine, medium, and coarse and common very Chroma: 1 or 2 fine roots; common very fine and fine pores; Texture (less than 2 mm): Loam slightly effervescent; moderately alkaline (pH Clay content: 15 to 35 percent 8.0); gradual smooth boundary. Content of rock fragments: 0 to 15 percent gravel Bk1—10 to 18 inches; light brownish gray (2.5Y 6/2) Calcium carbonate equivalent: 2 to 5 percent clay loam, dark grayish brown (2.5Y 4/2) moist; Reaction: pH 6.6 to 7.8 Sweet Grass County Area, Montana—Part I 67

A2 horizon Farnuf Series Hue: 10YR or 2.5Y Value: 4 or 5 dry; 2 or 3 moist Depth class: Very deep (greater than 60 inches) Chroma: 1 to 3 Drainage class: Well drained Texture (less than 2 mm): Loam, clay loam, or Permeability: Moderate (0.6 to 2.0 inches/hour) silty clay loam Landform: Fan, hill, moraine, stream terrace, terrace, Clay content: 18 to 35 percent fan on escarpment, swale on escarpment, fan on Content of rock fragments: 0 to 15 percent gravel plain, and swale on plain Calcium carbonate equivalent: 2 to 15 percent Parent material: Loamy alluvium or loamy Reaction: pH 6.6 to 8.4 glaciofluvial deposits Slope range: 0 to 35 percent Bk horizons Elevation range: 3,900 to 6,200 feet Hue: 10YR or 2.5Y Mean annual precipitation: 15 to 20 inches Value: 5 or 6 dry; 3 or 4 moist Mean annual air temperature: 39 to 45 degrees F Chroma: 2 or 3 Frost-free period: 70 to 115 days Redox concentrations: None to few; chroma of 3 or 4 Taxonomic Class: Fine-loamy, mixed, superactive, Texture (less than 2 mm): Loam, silt loam, or clay frigid Typic Argiustolls loam Clay content: 18 to 35 percent Typical Pedon Content of rock fragments: 0 to 15 percent gravel Farnuf loam, in an area of Farnuf loam, 8 to Calcium carbonate equivalent: 5 to 15 percent 15 percent slopes, in an area of hayland, 100 feet Reaction: pH 6.6 to 8.4 south and 300 feet east of the northwest corner of Bg horizon sec. 10, T. 3 N., R. 13 E.; USGS Battleship Butte Hue: 10YR, 2.5Y, or 5Y topographic quadrangle (lat. 46o01'52" N.; long. Value: 5 or 6 dry; 3 or 4 moist 110o06'04" W.) Chroma: 1 or 2 Ap—0 to 5 inches; grayish brown (10YR 5/2) loam, Redox concentrations: Few to many; chroma of 6 very dark grayish brown (10YR 3/2) moist; Redox depletions: None to common; chroma of 0 moderate medium granular structure; soft, very or 1 friable, slightly sticky, slightly plastic; few medium Texture (less than 2 mm): Loam, silt loam, or clay and coarse and common very fine and fine roots; loam with thin strata of sandy loam, loamy many very fine and fine pores; 5 percent gravel; sand, or clay loam neutral (pH 7.0); clear smooth boundary. Clay content: 18 to 30 percent Bt1—5 to 9 inches; brown (10YR 5/3) loam, very dark Content of rock fragments: 0 to 15 percent gravel grayish brown (10YR 3/2) moist; weak medium Calcium carbonate equivalent: 2 to 15 percent prismatic structure parting to moderate coarse Reaction: pH 6.6 to 8.4 subangular blocky; slightly hard, friable, slightly 2Cg horizon sticky, slightly plastic; few medium and common Hue: 10YR, 2.5Y, or 5Y very fine and fine roots; many very fine and fine Value: 5 to 7 dry; 3 or 4 moist pores; few faint patchy brown (10YR 4/3) moist; Chroma: 1 or 2 clay films on faces of peds and lining pores; 10 Redox concentrations: Few to many; chroma of 6 percent gravel; neutral (pH 7.0); gradual smooth Redox depletions: None to common; chroma of 0 boundary. or 1 Bt2—9 to 15 inches; grayish brown (10YR 5/2) clay Texture (less than 2 mm): Stratified sandy loam, loam, dark grayish brown (10YR 4/2) moist; loamy sand, very fine sandy loam, or sand moderate coarse subangular blocky structure; Clay content: 0 to 10 percent slightly hard, friable, moderately sticky, Content of rock fragments: 0 to 60 percent—0 to moderately plastic; few medium and common 5 percent cobbles; 0 to 55 percent gravel very fine and fine roots; many very fine and fine Calcium carbonate equivalent: 0 to 15 percent pores; common faint discontinuous brown (10YR Reaction: pH 6.6 to 8.4 4/3) moist; clay films on faces of peds and 68 Soil Survey

lining pores; 10 percent gravel; slightly alkaline Bk horizons (pH 7.4); clear smooth boundary. Hue: 7.5YR, 10YR, or 2.5Y Bk1—15 to 23 inches; light brownish gray (2.5Y 6/2) Value: 5 to 7 dry; 4 to 6 moist clay loam, dark grayish brown (2.5Y 4/2) moist; Chroma: 2 to 4 moderate coarse subangular blocky structure; Texture (less than 2 mm): Loam, clay loam, or silt moderately hard, friable, moderately sticky, loam moderately plastic; few fine, medium, and coarse Clay content: 20 to 35 percent roots; few fine soft masses and common threads Content of rock fragments: 0 to 35 percent gravel of lime; 10 percent gravel; strongly effervescent; Calcium carbonate equivalent: 5 to 15 percent moderately alkaline (pH 8.2); clear wavy Reaction: pH 7.4 to 8.4 boundary. Bk2—23 to 45 inches; light brownish gray (2.5Y 6/2) clay loam, grayish brown (2.5Y 5/2) moist; weak Fifer Series coarse subangular blocky structure; slightly hard, Depth class: Shallow (10 to 20 inches) friable, moderately sticky, moderately plastic; few Drainage class: Well drained fine and medium roots; common fine soft masses Permeability: Moderate (0.6 to 2.0 inches/hour) and threads of lime; 5 percent gravel; violently Landform: Mountain effervescent; moderately alkaline (pH 8.4); Parent material: Loamy residuum weathered from gradual smooth boundary. sandstone and shale or from sandstone and Bk3—45 to 60 inches; light brownish gray (2.5Y 6/2) siltstone clay loam, grayish brown (2.5Y 5/2) moist; weak Slope range: 2 to 60 percent coarse subangular blocky structure; slightly hard, Elevation range: 5,500 to 7,500 feet friable, moderately sticky, moderately plastic; few Mean annual precipitation: 20 to 25 inches fine and medium soft masses of lime; 5 percent Mean annual air temperature: 36 to 38 degrees F gravel; violently effervescent; moderately alkaline Frost-free period: 50 to 70 days (pH 8.4). Range in Characteristics Taxonomic Class: Loamy, mixed, superactive, shallow Ustic Haplocryolls Soil temperature: 38 to 47 degrees F Moisture control section: Between 4 and 12 inches Typical Pedon Thickness of the mollic epipedon: 7 to 15 inches Fifer loam, in an area of Fifer-Cheadle-Monaberg Depth to the Bk horizon: 10 to 25 inches complex, 25 to 60 percent slopes, in an area of Note: Some pedons have BC and C horizons of rangeland, 2,500 feet south and 1,900 feet west of stratified materials. the northeast corner of sec. 14, T. 2 N., R. 12 E.; A horizon USGS Raspberry Butte topographic quadrangle Hue: 10YR or 2.5Y (lat. 45o55'19" N.; long. 110o11'50" W.) Value: 3 to 5 dry; 2 or 3 moist A1—0 to 3 inches; dark grayish brown (10YR 4/2) Chroma: 2 or 3 loam, very dark grayish brown (10YR 3/2) moist; Texture (less than 2 mm): Loam moderate fine granular structure; soft, friable, Clay content: 15 to 27 percent nonsticky, nonplastic; many fine and medium Content of rock fragments: 0 to 35 percent—0 to roots; many very fine and fine pores; neutral 20 percent stones and cobbles; 0 to 15 percent (pH 7.2); clear smooth boundary. gravel A2—3 to 8 inches; grayish brown (10YR 5/2) loam; Reaction: pH 6.1 to 7.8 very dark grayish brown (10YR 3/2) moist; weak Bt horizons fine and medium subangular blocky structure; Hue: 7.5YR, 10YR, or 2.5Y slightly hard, friable, slightly sticky, slightly plastic; Value: 3 to 6 dry; 2 to 4 moist common fine and medium roots; many very fine Chroma: 2 to 4 and fine pores; slightly effervescent; neutral Texture (less than 2 mm): Loam, clay loam, or (pH 7.2); clear wavy boundary. silty clay loam Bk—8 to 16 inches; light brownish gray (2.5Y 6/2) Clay content: 25 to 35 percent gravelly loam; dark grayish brown (2.5Y 4/2) Content of rock fragments: 0 to 35 percent gravel moist; weak fine subangular blocky structure; Reaction: pH 6.1 to 7.8 slightly hard, friable; slightly sticky and slightly Sweet Grass County Area, Montana—Part I 69

plastic; common very fine and fine roots; common Typical Pedon very fine and fine pores; few patchy carbonate coats on undersides of rock fragments; few fine Foolhen mucky loam in an area of Foolhen, stony- soft masses of lime; 15 percent gravel; strongly Tibkey, bouldery complex, 0 to 8 percent slopes, in an effervescent; slightly alkaline (pH 7.8); clear area of wet meadow, 2,225 feet south and 1,100 feet smooth boundary. west of the northeast corner of sec. 6, T. 3 N., R. 3 W.; Cr—16 to 60 inches; calcareous soft sandstone; Jefferson County, Montana. strongly effervescent; slightly alkaline (pH 7.8). Oe—0 to 1 inch; mat of partially decomposed organic Range in Characteristics matter and roots. A1—1 to 5 inches; black (5Y 2.5/2) mucky loam, Soil temperature: 39 to 46 degrees F black (10YR 2/1) moist; weak fine granular Moisture control section: Between 4 and 12 inches structure; soft, very friable, slightly sticky, Thickness of the mollic epipedon: 7 to 12 inches nonplastic; common medium and many very Depth to the Cr horizon: 10 to 20 inches fine and fine roots; 4 percent rounded cobbles; A horizons 10 percent rounded gravel; neutral (pH 6.8); clear Hue: 10YR or 2.5Y wavy boundary. Value: 3 to 5 dry; 2 or 3 moist A2—5 to 14 inches; black (5Y 2.5/2) mucky silt loam, Chroma: 1 or 2 black (10YR 2/1) moist; few distinct reddish Texture (less than 2 mm): Loam brown (5YR 5/4) redox concentrations; moderate Clay content: 18 to 27 percent medium prismatic structure parting to moderate Content of rock fragments: 0 to 35 percent—0 to fine subangular blocky; hard, very friable, slightly 5 percent cobbles; 0 to 30 percent gravel sticky, nonplastic; many very fine and fine roots; Reaction: pH 6.6 to 7.8 many very fine pores; 5 percent rounded cobbles; 20 percent rounded gravel; neutral (pH 6.8); Bk horizon gradual wavy boundary. Hue: 10YR, 2.5Y, or 5Y Bw—14 to 22 inches; pale brown (10YR 6/3) gravelly Value: 5 to 7 dry; 4 to 6 moist sandy clay loam, dark brown (10YR 3/3) moist; Chroma: 1 to 3 many distinct yellowish red (5YR 5/6) redox Texture (less than 2 mm): Loam, clay loam, or concentrations; common faint very dark gray silty clay loam (5Y 3/1) redox depletions; moderate medium Clay content: 18 to 35 percent subangular blocky structure; hard, friable, Content of rock fragments: 0 to 35 percent—0 to moderately sticky, slightly plastic; many very fine 5 percent cobbles; 0 to 30 percent gravel and fine roots; few very fine pores; 5 percent Calcium carbonate equivalent: 5 to 15 percent rounded cobbles; 20 percent rounded gravel; Reaction: pH 7.4 to 8.4 neutral (pH 7.0); gradual wavy boundary. Cg1—22 to 33 inches; brown (10YR 5/3) gravelly Foolhen Series sandy clay loam, brown (10YR 4/3) moist; many distinct yellowish red (5YR 5/6) redox Depth class: Very deep (greater than 60 inches) concentrations; common faint very dark gray Drainage class: Very poorly drained (5Y 3/1) redox depletions; weak medium Permeability: Moderate (0.6 to 2.0 inches/hour) subangular blocky structure; hard, friable, Landform: Depression on flood plain moderately sticky, slightly plastic; many very Parent material: Alluvium fine and fine roots; few very fine pores; 5 percent Slope range: 0 to 2 percent rounded cobbles; 20 percent rounded gravel; Elevation range: 6,000 to 7,500 feet neutral (pH 7.2); gradual wavy boundary. Mean annual precipitation: 20 to 25 inches Cg2—33 to 45 inches; yellowish brown (10YR 5/4) Mean annual air temperature: 36 to 38 degrees F cobbly sandy clay loam, brown (10YR 4/3) moist; Frost-free period: 50 to 70 days many distinct yellowish red (5YR 5/6) redox concentrations; few faint very dark gray (5Y 3/1) Taxonomic Class: Fine-loamy, mixed, superactive redox depletions; weak coarse subangular blocky Typic Cryaquolls structure; slightly hard, friable, moderately sticky, 70 Soil Survey

slightly plastic; many very fine and fine roots; Permeability: Moderately rapid (2 to 6 inches/hour) few very fine pores; 15 percent rounded cobbles; Landform: Stream terrace 15 percent rounded gravel; neutral (pH 7.2); Parent material: Gravelly alluvium gradual irregular boundary. Slope range: 2 to 4 percent Cg3—45 to 60 inches; yellowish brown (10YR 5/4) Elevation range: 3,750 to 5,200 feet very gravelly sandy clay loam, dark yellowish Mean annual precipitation: 10 to 14 inches brown (10YR 4/4) moist; many distinct yellowish Mean annual air temperature: 43 to 46 degrees F red (5YR 5/6) redox concentrations; few faint very Frost-free period: 95 to 125 days dark gray (5Y 3/1) redox depletions; massive; slightly hard, friable, moderately sticky, slightly Taxonomic Class: Loamy-skeletal, mixed, plastic; common very fine and fine roots; few superactive, frigid Aridic Haplustolls very fine pores; 10 percent rounded cobbles; Typical Pedon 35 percent rounded gravel; neutral (pH 7.2). Frenchcreek very gravelly loam, 2,000 feet north Range in Characteristics and 800 feet east of the southwest corner of sec. 29, Soil temperature: 36 to 42 degrees F T. 13 N., R. 3 W.; Lewis and Clark County, Montana. Moisture control section: Between 4 and 12 inches A—0 to 5 inches; grayish brown (10YR 5/2) very Thickness of the mollic epipedon: 10 to 19 inches gravelly loam, very dark grayish brown (10YR Depth to the seasonal high water table: Ponded to 3/3) moist; moderate very thin platy structure 12 inches parting to moderate very fine granular; slightly Surface stones: 0.0 to 0.1 percent hard, very friable, slightly sticky, slightly plastic; A horizons many very fine roots; 55 percent angular gravel; Hue: 10YR, 2.5Y, or 5Y slightly acid (pH 6.1); clear smooth boundary. Value: 2, 2.5, or 3 dry Bw1—5 to 12 inches; brown (10YR 5/3) very gravelly Chroma: 1 or 2 loam, dark brown (10YR 4/3) moist; weak fine Texture (less than 2 mm): Loam, mucky loam, and medium subangular blocky structure; hard, mucky silt loam, or sandy loam friable, slightly sticky, slightly plastic; common Clay content: 10 to 20 percent very fine roots; many very fine tubular and Content of rock fragments: 5 to 25 percent—0 to interstitial pores; 60 percent angular gravel; 5 percent cobbles; 5 to 20 percent gravel slightly acid (pH 6.2); gradual smooth boundary. Reaction: pH 6.1 to 7.3 Bw2—12 to 26 inches; pale brown (10YR 6/3) extremely gravelly sandy loam, dark brown Bw horizon (10YR 4/3) moist; weak very fine granular Hue: 10YR, 2.5Y, or 5Y structure; soft, very friable, slightly sticky, Texture (less than 2 mm): Sandy clay loam, loam, nonplastic; common very fine roots; 70 percent or sandy loam angular gravel; slightly acid (pH 6.4); gradual Clay content: 18 to 30 percent smooth boundary. Content of rock fragments: 10 to 35 percent—0 to C1—26 to 36 inches; pale brown (10YR 6/3) 10 percent cobbles; 10 to 25 percent gravel extremely gravelly loamy sand, dark brown (10YR Reaction: pH 6.1 to 7.3 4/3) moist; single grain; loose, slightly sticky; Cg horizons nonplastic; few very fine roots; 70 percent angular Hue: 10YR, 2.5Y, or 5Y gravel; neutral (pH 6.6); gradual smooth Value: 4 or 5 moist; 5 to dry boundary. Texture (less than 2 mm): Loam, sandy clay loam, C2—36 to 60 inches; very pale brown (10YR 7/4) or sandy loam extremely gravelly loam, yellowish brown (10YR Clay content: 18 to 27 percent 5/4) moist; massive; slightly hard, friable, Content of rock fragments: 0 to 50 percent—0 to moderately sticky and slightly plastic; 70 percent 15 percent cobbles; 0 to 35 percent gravel angular gravel; neutral (pH 6.8). Reaction: pH 5.6 to 7.3 Range in Characteristics Frenchcreek Series Soil temperature: 42 to 47 degrees F Moisture control section: Between 8 and 24 inches Depth class: Very deep (greater than 60 inches) Thickness of the mollic epipedon: 7 to 15 inches; may Drainage class: Well drained or may not include part of the Bw horizon Sweet Grass County Area, Montana—Part I 71

A horizon Gerdrum Series Hue: 5YR, 7.5R, or 10YR Value: 4 or 5 dry, 3 moist Depth class: Very deep (greater than 60 inches) Chroma: 2 or 3 Drainage class: Well drained Texture (less than 2 mm): Loam Permeability: Very slow (less than 0.06 inch/hour) Clay content: 15 to 25 percent Landform: Plain, stream terrace, and depression on Content of rock fragments: 15 to 70 percent—0 to terrace 15 percent stones and cobbles; 15 to Parent material: Clayey alluvium 55 percent angular gravel Slope range: 0 to 8 percent Reaction: pH 6.1 to 7.8 Elevation range: 3,750 to 5,600 feet Mean annual precipitation: 10 to 19 inches Bw1 horizon Mean annual air temperature: 39 to 45 degrees F Hue: 5YR, 7.5YR, or 10YR Frost-free period: 95 to 125 days Value: 4 to 6 dry; 3 or 4 moist Chroma: 3 or 4 Taxonomic Class: Fine, smectitic, frigid Torrertic Texture (less than 2 mm): Loam or sandy loam Natrustalfs Clay content: 15 to 25 percent Content of rock fragments: 30 to 80 percent—0 to Typical Pedon 15 percent stones and cobbles; 30 to 65 percent angular gravel Gerdrum clay loam, in an area of Gerdrum-Creed Reaction: pH 6.1 to 7.8 complex, 0 to 8 percent slopes, in an area of rangeland, 2,200 feet north and 2,600 feet east of Bw2 horizon the southwest corner of sec. 12, T. 3 N., R. 18 E.; Hue: 5YR, 7.5YR, or 10YR USGS Locomotive Butte SW topographic quadrangle Value: 5 to 7 dry; 4 or 5 moist (lat. 46o01'27" N.; long. 109o26'02" W.) Chroma: 2 to 4 Texture (less than 2 mm): Sandy loam or loam E—0 to 3 inches; light brownish gray (10YR 6/2) clay Clay content: 10 to 20 percent loam, grayish brown (10YR 5/2) moist; weak thin Content of rock fragments: 35 to 75 percent—0 to and medium platy structure; soft, very friable, 5 percent cobbles; 35 to 70 percent angular slightly sticky, slightly plastic; many very fine and gravel fine roots; many very fine and fine pores; neutral Reaction: pH 6.1 to 7.8 (pH 7.2); abrupt smooth boundary. Btn1—3 to 8 inches; grayish brown (2.5Y 5/2) silty C1 horizon clay, dark grayish brown (2.5Y 4/2) moist; Hue: 5YR, 7.5Y, or 10YR moderate medium columnar structure parting to Value: 5 to 7 dry; 4 or 5 moist strong medium subangular and angular blocky; Chroma: 2 to 4 very hard, firm, very sticky, very plastic; many Texture (less than 2 mm): Loamy sand or sandy very fine and fine roots compressed between ped loam faces; few very fine and fine pores; common Clay content: 5 to 15 percent distinct discontinuous dark yellowish brown Content of rock fragments: 50 to 80 percent—0 to (10YR 4/4) moist; clay films on faces of peds; 5 percent cobbles; 50 to 75 percent angular slightly alkaline (pH 7.6); clear smooth boundary. gravel Btn2—8 to 13 inches; grayish brown (2.5Y 5/2) silty Reaction: pH 6.1 to 7.8 clay, dark grayish brown (2.5Y 4/2) moist; strong C2 horizon medium and coarse subangular and angular Hue: 5YR, 7.5YR, or 10YR blocky structure; very hard, firm, very sticky, very Value: 6 or 7 dry, 4 or 5 moist plastic; common very fine and fine roots Chroma: 2 to 4 compressed between ped faces; few very fine Texture (less than 2 mm): Loam or sandy loam and fine pores; many distinct continuous dark Clay content: 10 to 20 percent yellowish brown (10YR 4/4) moist; clay films on Content of rock fragments: 60 to 80 percent—0 to faces of peds; slightly alkaline (pH 7.8); abrupt 5 percent angular cobbles; 60 to 75 percent smooth boundary. angular gravel Btnk—13 to 18 inches; light brownish gray (2.5Y 6/2) Reaction: pH 6.6 to 7.8 silty clay, grayish brown (2.5Y 5/2) moist; 72 Soil Survey

moderate coarse prismatic structure parting to Chroma: 2 to 4 moderate medium subangular and angular Texture (less than 2 mm): Clay, silty clay, or silty blocky; very hard, firm, very sticky, very plastic; clay loam few fine roots compressed between ped faces; Clay content: 35 to 55 percent few very fine and fine pores; few faint dark Content of rock fragments: 0 to 10 percent gravel yellowish brown (10YR 4/4) moist; clay films on Structure: Fine to coarse columnar and medium faces of peds; few fine and medium soft masses or coarse blocky of lime; strongly effervescent; moderately alkaline Hardness: Extremely or very hard when dry (pH 8.4); gradual smooth boundary. Electrical conductivity: 1 to 8 mmhos/cm Bknyz1—18 to 28 inches; light brownish gray (2.5Y Sodium adsorption ratio: 10 to 20 6/2) silty clay, grayish brown (2.5Y 5/2) moist; Reaction: pH 7.4 to 9.0 weak coarse prismatic structure; very hard, firm, Btnk horizon very sticky, very plastic; few fine roots; few very Hue: 10YR, 2.5Y, or 5Y fine and fine pores; common fine and medium Value: 5 to 7 dry; 4 to 6 moist soft masses of gypsum and other salts; common Chroma: 2 or 3 fine and medium soft masses of lime; strongly Texture (less than 2 mm): Clay, silty clay, clay effervescent; strongly alkaline (pH 8.6); gradual loam, or silty clay loam smooth boundary. Clay content: 35 to 55 percent Bknyz2—28 to 41 inches; light brownish gray (2.5Y Content of rock fragments: 0 to 10 percent gravel 6/2) silty clay, grayish brown (2.5Y 5/2) moist; Calcium carbonate equivalent: 5 to 15 percent weak medium and coarse prismatic structure; Electrical conductivity: 1 to 8 mmhos/cm very hard, firm, very sticky, very plastic; few very Sodium adsorption ratio: 10 to 20 fine and fine pores; many medium and coarse Reaction: pH 7.4 to 9.0 soft masses and nests of gypsum and other salts; common fine and medium soft masses and Bknyz horizons threads of lime; strongly effervescent; strongly Hue: 10YR, 2.5Y, or 5Y alkaline (pH 8.8); gradual smooth boundary. Value: 5 to 7 dry; 4 to 6 moist Bknyz3—41 to 60 inches; grayish brown (2.5Y 5/2) Chroma: 2 to 4 silty clay, dark grayish brown (2.5Y 4/2) moist; Texture (less than 2 mm): Clay, silty clay, clay weak coarse prismatic structure; very hard, firm, loam, or sandy clay loam very sticky, very plastic; common medium soft Clay content: 30 to 50 percent masses and nests of gypsum and other salts; few Content of rock fragments: 0 to 10 percent gravel fine and medium soft masses of lime; strongly Calcium carbonate equivalent: 5 to 15 percent effervescent; strongly alkaline (pH 8.8). Electrical conductivity: 8 to 16 mmhos/cm Sodium adsorption ratio: 13 to 30 Range in Characteristics Gypsum content: 1 to 5 percent Reaction: pH 7.9 to 9.0 Soil temperature: 42 to 47 degrees F Moisture control section: Between 4 and 12 inches Depth to the secondary carbonates horizon: 10 to Gilispie Series 24 inches Depth to gypsum: 10 to 28 inches Depth class: Shallow (10 to 20 inches) Note: Some pedons have an A horizon. Drainage class: Well drained Permeability: Moderate (0.6 to 2.0 inches/hour) E horizon Landform: Mountain Hue: 10YR or 2.5Y Parent material: Clayey residuum weathered from Value: 6 or 7 dry; 4 to 6 moist sandstone Chroma: 2 or 3 Slope range: 2 to 35 percent Texture (less than 2 mm): Clay loam Elevation range: 6,000 to 7,500 feet Clay content: 27 to 40 percent Mean annual precipitation: 20 to 25 inches Content of rock fragments: 0 to 15 percent gravel Mean annual air temperature: 36 to 38 degrees F Reaction: pH 6.6 to 7.8 Frost-free period: 50 to 70 days Btn horizons Hue: 10YR or 2.5Y Taxonomic Class: Loamy, mixed, superactive Lithic Value: 5 to 7 dry; 4 or 5 moist Argicryolls Sweet Grass County Area, Montana—Part I 73

Typical Pedon Bt1 horizon Hue: 7.5YR, 10YR, or 2.5Y Gilispie gravelly loam, in an area of Cheadle- Value: 3 to 6 dry; 2 to 5 moist Lymanson-Gilispie complex, 15 to 35 percent slopes, Chroma: 2 to 4 in an area of rangeland, 3,500 feet north and Texture (less than 2 mm): Loam or clay loam 1,800 feet east of the southwest corner of sec. 36, Clay content: 25 to 35 percent T. 2 N., R. 12 E.; USGS McLeod Basin topographic Content of rock fragments: 0 to 35 percent—0 to quadrangle (lat. 45o37'15" N.; long. 110o11'23" W.) 10 percent cobbles; 0 to 25 percent gravel A—0 to 7 inches; very dark grayish brown (10YR 3/2) Reaction: pH 6.1 to 7.3 gravelly loam, black (10YR 2/1) moist; weak fine Bt2 horizon granular structure; soft, very friable, slightly sticky, Hue: 10YR, 2.5Y, or 5Y slightly plastic; many very fine and fine roots; Value: 5 to 7 dry; 3 to 5 moist many very fine and fine pores; 22 percent Chroma: 2 to 4 channers; slightly acid (pH 6.4); abrupt smooth Texture (less than 2 mm): Clay, clay loam, or loam boundary. Clay content: 20 to 45 percent Bt1—7 to 13 inches; brown (10YR 5/3) clay loam, Content of rock fragments: 15 to 35 percent—5 to dark brown (10YR 4/3) moist; moderate medium 15 percent stones and cobbles; 10 to 20 subangular blocky structure; slightly hard, friable, percent gravel moderately sticky, moderately plastic; many very Reaction: pH 6.6 to 7.3 fine and fine roots; many very fine and fine pores; many distinct continuous dark yellowish brown (10YR 4/6) moist; clay films on faces of peds and Greybear Series lining pores; 5 percent gravel; 5 percent cobbles; neutral (pH 6.6); clear smooth boundary. Depth class: Deep (40 to 60 inches) Bt2—13 to 16 inches; light brownish gray (10YR 6/2) Drainage class: Well drained cobbly clay, grayish brown (10YR 5/2) moist; Permeability: Moderately slow (0.2 to 0.6 inch/hour) moderate medium subangular blocky structure; Landform: Swale on plain moderately hard, firm, very sticky, very plastic; Parent material: Clayey alluvium over clayey common very fine and fine roots; common very residuum weathered from shale fine and fine pores; common distinct patchy dark Slope range: 2 to 15 percent yellowish brown (10YR 4/6) moist; clay films on Elevation range: 3,750 to 5,200 feet faces of peds and rock fragments; 10 percent Mean annual precipitation: 10 to 14 inches gravel; 15 percent cobbles; neutral (pH 6.8); Mean annual air temperature: 43 to 46 degrees F abrupt smooth boundary. Frost-free period: 95 to 125 days R—16 inches; hard sandstone bedrock; noneffervescent. Taxonomic Class: Fine, smectitic, frigid Aridic Haplustolls Range in Characteristics Typical Pedon Soil temperature: 44 to 46 degrees F Moisture control section: Between 4 and 12 inches Greybear clay loam, in an area of Greybear-Rentsac Thickness of the mollic epipedon: 5 to 15 inches complex, 2 to 15 percent slopes, in an area of Depth to bedrock: 10 to 20 inches rangeland, 1,900 feet south and 850 feet west of the Note: The weighted average of the clay content of the northeast corner of sec. 27, T. 1 N., R. 13 E.; USGS Bt horizon does not exceed 35 percent. Carney topographic quadrangle (lat. 45o48'31" N.; long. 110o05'15" W.) A horizon Hue: 7.5YR, 10YR, or 2.5Y A—0 to 2 inches; brown (7.5YR 5/2) clay loam, dark Value: 3 to 5 dry; 2 or 3 moist brown (7.5YR 3/2) moist; weak medium granular Chroma: 1 or 2 structure; slightly hard, friable, moderately sticky, Texture (less than 2 mm): Loam moderately plastic; many very fine to medium Clay content: 20 to 25 percent roots; many very fine and fine pores; slightly Content of rock fragments: 0 to 35 percent—0 to effervescent; neutral; (pH 7.2); abrupt smooth 10 percent cobbles; 0 to 25 percent gravel or boundary. channers Bw—2 to 8 inches; brown (7.5YR 4/2) clay loam, dark Reaction: pH 6.1 to 7.3 brown (7.5YR 3/2) moist; weak fine and medium 74 Soil Survey

subangular blocky structure; moderately hard, Clay content: 35 to 45 percent firm, moderately sticky, moderately plastic; Content of rock fragments: 0 to 5 percent gravel common very fine and fine roots; many very fine Reaction: pH 7.4 to 9.0 and fine pores; strongly effervescent; slightly Bk1 and Bk2 horizons alkaline (pH 7.8); clear wavy boundary. Hue: 2.5YR, 5YR, or 7.5YR Bk1—8 to 22 inches; reddish gray (5YR 5/2) clay Value: 4 to 6 dry; 3 to 5 moist; values of 5 dry and loam, dark reddish gray (5YR 4/2) moist; strong 3 moist with low chroma are lithochromatic. medium and coarse prismatic structure; very Chroma: 2 or 3; hard, firm, very sticky, very plastic; common very Texture (less than 2 mm): Clay loam, silty clay fine and fine roots; common very fine and fine loam, or silty clay pores; common fine and medium masses and Clay content: 35 to 45 percent threads of lime; violently effervescent; moderately Content of rock fragments: 0 to 5 percent gravel alkaline (pH 8.4); clear smooth boundary. Calcium carbonate equivalent: 5 to 15 percent Bk2—22 to 35 inches; dark reddish gray (5YR 4/2) Reaction: pH 7.9 to 9.0 clay loam, dark reddish brown (5YR 3/2) moist; moderate medium angular blocky structure; very Bk3 horizon hard, friable, very sticky, very plastic; few very Hue: 2.5YR, 5YR, or 7.5YR fine and fine roots; common very fine and fine Value: 4 to 6 dry; 3 to 5 moist; values of 5 dry and pores; common fine soft masses and threads of 3 moist with low chroma are lithochromatic. lime; violently effervescent; strongly alkaline Chroma: 2 or 3 (pH 8.6); clear smooth boundary. Texture (less than 2 mm): Clay loam, silty clay Bk3—35 to 56 inches; dark reddish gray (5YR 4/2) loam, or silty clay gravelly clay loam, dark reddish brown (5YR 3/2) Clay content: 35 to 45 percent moist; weak medium angular blocky structure; Content of rock fragments: 5 to 25 percent gravel very hard, very firm, very sticky, very plastic; few Calcium carbonate equivalent: 5 to 15 percent very fine roots; few very fine and fine pores; few Reaction: pH 7.9 to 9.0 fine soft masses of lime; 15 percent gravel; strongly effervescent; moderately alkaline (pH 8.4); clear smooth boundary. Havre Series Cr—56 to 60 inches; dark gray (5YR 4/1) stratified Depth class: Very deep (greater than 60 inches) shale and siltstone bedrock, very dark gray (5YR Drainage class: Well drained 3/1) moist; slightly effervescent. Permeability: Moderate (0.6 to 2.0 inches/hour) Range in Characteristics Landform: Flood plain Parent material: Loamy alluvium Soil temperature: 41 to 46 degrees F Slope range: 0 to 4 percent Moisture control section: Between 4 and 12 inches Elevation range: 3,750 to 5,200 feet Thickness of the mollic epipedon: 7 to 12 inches Mean annual precipitation: 10 to 14 inches Depth to the Bk horizon: 8 to 20 inches Mean annual air temperature: 43 to 46 degrees F Depth to the Cr horizon: 40 to 60 inches Frost-free period: 95 to 130 days A horizon Hue: 5YR, 7.5YR, or 10YR Taxonomic Class: Fine-loamy, mixed, superactive, Value: 5 dry; 3 moist calcareous, frigid Aridic Ustifluvents Chroma: 2 or 3 Typical Pedon Texture (less than 2 mm): Clay loam Clay content: 30 to 40 percent Havre loam, in an area of Havre loam, 0 to 2 percent Content of rock fragments: 0 to 5 percent gravel slopes, 1,400 feet north and 3,000 feet east of the Reaction: pH 6.6 to 7.8 southwest corner of sec. 11, T. 2 S., R. 19 E.; Stillwater County, Montana. Bw horizon Hue: 2.5YR, 5YR, or 7.5YR Ap—0 to 6 inches; light brownish gray (2.5Y 6/2) Value: 4 to 6 dry; 3 to 5 moist loam, grayish brown (2.5Y 5/2) moist; weak thin Chroma: 2 or 3 platy structure parting to weak fine granular; soft, Texture (less than 2 mm): Clay loam, silty clay friable, nonsticky, nonplastic; few very fine and loam, or silty clay fine roots and pores; strongly effervescent; Sweet Grass County Area, Montana—Part I 75

moderately alkaline (pH 7.9); clear wavy Chroma: 2 or 3 boundary. Texture (less than 2 mm): Silt loam, clay loam, or C1—6 to 9 inches; light brownish gray (10YR 6/2) sandy clay loam, which consist of strata of silt loam, grayish brown (10YR 5/2) moist; weak fine loam, fine sandy loam, very fine sandy loam, angular blocky structure parting to weak fine silty clay loam, and clay loam granular; soft, friable, nonsticky, nonplastic; few Clay content: 18 to 35 percent very fine roots and pores; strongly effervescent; Calcium carbonate equivalent: 1 to 10 percent moderately alkaline (pH 7.9); clear wavy Effervescence: Slight or strongly boundary. Electrical conductivity: 0 to 16 mmhos/cm C2—9 to 48 inches; light brownish gray (10YR 6/2) Reaction: pH 7.4 to 9.0 loam, grayish brown (10YR 5/2) moist; massive; soft, friable, nonsticky, nonplastic; few very fine roots and pores; strongly effervescent; strongly Hinterland Series alkaline (pH 8.4); clear smooth boundary. C3—48 to 60 inches; light gray (10YR 7/1) stratified Depth class: Shallow (10 to 20 inches) silt loam, fine sandy loam, and clay, gray (10YR Drainage class: Well drained 5/1) moist; massive; soft, friable, moderately Permeability: Moderately slow (0.2 to 0.6 inch/hour) sticky, moderately plastic; 5 percent lime-coated Landform: Hill, knoll on plain, structural bench on gravel; strongly effervescent; moderately alkaline plain, and swale on plain (pH 8.4). Parent material: Residuum weathered from sandstone Range in Characteristics Slope range: 0 to 35 percent Soil temperature: 40 to 47 degrees F Elevation range: 3,750 to 5,200 feet Moisture control section: Between 4 and 12 inches Mean annual precipitation: 10 to 14 inches Note: Some pedons have between 15 and 60 percent Mean annual air temperature: 43 to 46 degrees F coarse fragments below a depth of 40 inches. Frost-free period: 95 to 125 days Ap horizon Taxonomic Class: Clayey, smectitic, frigid Aridic Hue: 10YR or 2.5Y Lithic Argiustolls Value: 5 or 6 dry; 4 or 5 moist Chroma: 2 or 3 Typical Pedon Texture (less than 2 mm): Loam Hinterland clay loam, in an area of Hinterland clay Clay content: 15 to 27 percent loam, 0 to 8 percent slopes, in an area of cropland, Calcium carbonate equivalent: 1 to 10 percent 1,500 feet south and 1,000 feet west of the northeast Effervescence: None to strongly corner of sec. 1, T. 2 N., R. 17 E.; USGS Stephens Hill Electrical conductivity: 0 to 4 mmhos/cm NE topographic quadrangle (lat. 45o57'18" N.; long. Sodium adsorption ratio: 0 to 4 109o33'08" W.) Reaction: pH 6.1 to 8.4 Ap—0 to 7 inches; grayish brown (10YR 5/2) clay C1 horizon loam, dark brown (10YR 3/3) moist; weak fine Hue: 10YR, 2.5Y, or 5Y granular structure; soft, very friable, slightly sticky, Value: 5 or 6 dry; 4 or 5 moist slightly plastic; common very fine and fine roots; Chroma: 2 or 3 many very fine pores; slightly alkaline (pH 7.6); Texture (less than 2 mm): Silt loam, clay loam, or abrupt smooth boundary. sandy clay loam, which consist of strata of silt Bt1—7 to 10 inches; brown (10YR 5/3) clay loam, loam, fine sandy loam, very fine sandy loam, dark brown (10YR 3/3) moist; moderate medium silty clay loam, and clay loam angular blocky structure; moderately hard, friable, Clay content: 18 to 35 percent moderately sticky, moderately plastic; few fine Calcium carbonate equivalent: 1 to 10 percent and medium and common very fine roots; Effervescence: Slight or strongly common very fine and fine pores; common faint Electrical conductivity: 0 to 16 mmhos/cm discontinuous dark yellowish brown (10YR 3/4) Reaction: pH 7.4 to 9.0 moist; clay films on faces of peds; slightly alkaline C2 and C3 horizon (pH 7.4); clear smooth boundary. Hue: 10YR, 2.5Y, or 5Y Bt2—10 to 13 inches; yellowish brown (10YR 5/4) Value: 5 to 7 dry; 4 or 5 moist channery clay loam, brown (10YR 4/3) moist; 76 Soil Survey

moderate medium and coarse angular blocky Permeability: Slow (0.06 to 0.20 inch/hour) structure parting to moderate fine subangular Landform: Flood plain blocky; moderately hard, friable, very sticky, very Parent material: Clayey alluvium plastic; common very fine roots; common very Slope range: 0 to 2 percent fine pores; common distinct discontinuous dark Elevation range: 3,750 to 6,000 feet yellowish brown (10YR 3/4) moist; clay films on Mean annual precipitation: 10 to 19 inches faces of peds and rock fragments; 25 percent Mean annual air temperature: 43 to 46 degrees F channers; slightly alkaline (pH 7.4); abrupt Frost-free period: 85 to 125 days smooth boundary. R—13 inches; hard fractured sandstone. Taxonomic Class: Fine, mixed, superactive, calcareous, frigid Fluvaquentic Endoaquolls Range in Characteristics Typical Pedon Soil temperature: 42 to 47 degrees F Moisture control section: Between 4 and 12 inches Klayent clay loam, 1,900 feet south and 2,200 feet Thickness of the mollic epipedon: 7 to 12 inches west of the northeast corner of sec. 10, T. 18 N., Depth to bedrock: 10 to 20 inches R. 22 E.; Fergus County, Montana. A horizon Ap—0 to 5 inches; very dark grayish brown (10YR Hue: 7.5YR, 10YR, or 2.5Y 3/2) clay loam, dark grayish brown (10YR 4/2) Value: 5 dry; 2 or 3 moist dry; weak thin and medium platy structure; hard, Chroma: 2 or 3 friable, moderately sticky, moderately plastic; few Texture (less than 2 mm): Clay loam coarse and many fine, very fine, and medium Clay content: 27 to 35 percent roots; slightly effervescent; moderately alkaline Content of rock fragments: 0 to 15 percent—0 to (pH 8.0); abrupt wavy boundary. 5 percent cobbles; 0 to 10 percent gravel or Bw—5 to 14 inches; very dark gray (10YR 3/1) clay, channers dark gray (10YR 4/1) dry; moderate coarse Reaction: pH 6.6 to 7.8 prismatic structure parting to moderate fine and medium subangular blocky; hard, friable, Bt1 horizon moderately sticky, moderately plastic; few coarse, Hue: 7.5YR, 10YR, or 2.5Y common medium, and many very fine and fine Value: 4 or 5 dry; 2 or 3 moist roots; common medium and many very fine and Chroma: 2 or 3 fine pores; 1 percent gravel; few fine masses of Texture (less than 2 mm): Clay loam or silty clay gypsum and other salts; slightly effervescent; loam moderately alkaline (pH 8.4); clear irregular Clay content: 27 to 40 percent boundary. Content of rock fragments: 0 to 15 percent—0 to Bkyz—14 to 23 inches; very dark gray (10YR 3/1) 5 percent cobbles; 0 to 10 percent gravel or clay, light brownish gray (2.5Y 6/2) dry; organic channers coatings on faces of peds are light brownish gray Reaction: pH 6.6 to 7.8 (2.5Y 6/2) and grayish brown (2.5Y 5/2) dry; few Bt2 horizon fine distinct very pale brown (10YR 7/4) redox Hue: 7.5YR, 10YR, or 2.5Y concentrations; weak coarse prismatic structure Value: 4 or 5 dry; 3 or 4 moist parting to weak fine and medium subangular Chroma: 2 to 4 blocky; very hard, friable, moderately sticky, Texture (less than 2 mm): Clay loam or clay moderately plastic; few medium and many very Clay content: 35 to 50 percent fine and fine roots; common medium and many Content of rock fragments: 15 to 35 percent—0 to very fine and fine pores; many fine, medium, and 5 percent cobbles; 15 to 30 percent gravel or coarse distinct masses of lime; many fine, channers medium, and coarse distinct masses of gypsum Reaction: pH 6.6 to 7.8 and other salts; strongly effervescent; strongly alkaline (pH 8.8); clear wavy boundary. Byzg—23 to 30 inches; gray (5Y 5/1) clay, light gray Klayent Series (5Y 6/1) dry; common fine distinct very pale brown (10YR 7/4) redox concentrations; weak Depth class: Very deep (greater than 60 inches) coarse prismatic structure parting to weak Drainage class: Poorly drained medium subangular blocky; very hard, firm, very Sweet Grass County Area, Montana—Part I 77

sticky, moderately plastic; few medium and Chroma: 1 or 2 common very fine and fine roots; common Texture (less than 2 mm): Clay loam, clay, or silty medium and many very fine and fine pores; many clay loam medium and coarse distinct masses of gypsum Clay content: 35 to 50 percent and other salts; disseminated lime; slightly Calcium carbonate equivalent: 5 to 15 percent effervescent; strongly alkaline (pH 8.8); clear Content of rock fragments: 0 to 5 percent gravel wavy boundary. Reaction: pH 7.9 to 9.0 Cyzg1—30 to 43 inches; gray (5Y 5/1) clay loam, Bkyz horizon stratified with thin lenses of light clay, light gray Hue: 10YR, 2.5Y, or 5Y matrix; 10YR or 2.5Y (5Y 6/1) dry; many fine and medium distinct redox concentrations brownish yellow (10YR 6/8) redox concentrations; Value: 4 to 6 matrix, 6 to 8 redox concentrations massive; extremely hard, firm, moderately sticky, dry; 3 or 4 matrix, 6 or 7 redox concentrations moderately plastic; few very fine and fine roots; moist common very fine and fine pores; many fine, Chroma: 1 or 2 matrix; 2, 4, 6, or 8 redox medium, and coarse distinct masses of gypsum concentrations and other salts; disseminated lime; strongly Texture (less than 2 mm): Silty clay loam, clay effervescent; strongly alkaline (pH 8.6); gradual loam, or clay wavy boundary. Clay content: 35 to 50 percent Cyzg2—43 to 67 inches; greenish gray (5GY 6/1) Content of rock fragments: 0 to 5 percent gravel sandy clay loam stratified with thin lenses of loam Calcium carbonate equivalent: 5 to 15 percent and sandy clay, greenish gray (5GY 6/1) dry; Gypsum content: 0 to 1 percent many medium and coarse distinct brownish Electrical conductivity: 2 to 8 mmhos/cm yellow (10YR 6/8) and olive brown (2.5Y 4/4) Reaction: pH 7.9 to 9.0 redox concentrations; massive; extremely hard, firm, moderately sticky, moderately plastic; few Byzg horizon very fine roots; few very fine and fine pores; Hue: 2.5Y, 5Y, or 5GY matrix; 10YR or 2.5Y redox common fine and medium and few coarse concentrations masses of gypsum and other salts; disseminated Value: 6 or 7 matrix, 5 or 7 redox concentrations lime; strongly effervescent; strongly alkaline dry; 4 to 6 matrix, 4 or 7 redox concentrations (pH 8.6). moist Chroma: 1 or 2 matrix, 4, 6, or 8 redox Range in Characteristics concentrations Redox concentrations: Common or many; faint to Soil temperature: 44 to 47 degrees F prominent Moisture control section: Between 4 and 12 inches Texture (less than 2 mm): Clay loam, silty clay Thickness of the mollic epipedon: 10 to 16 inches loam, clay, or sandy clay loam Depth to lime: 10 to 16 inches Clay content: 30 to 45 percent Depth to the Bk horizon: 12 to 20 inches Content of rock fragments: 0 to 15 percent gravel Depth to the seasonal high water table: 12 to Calcium carbonate equivalent: 5 to 10 percent 24 inches Gypsum content: 1 to 3 percent Notes: Few threads of lime and masses of salts may Electrical conductivity: 2 to 8 mmhos/cm not be present in the Bw horizon. Some pedons Reaction: pH 7.9 to 9.0 have a Bkyzg or a Ckyzg horizon. Cyzg horizons A horizon Hue: 2.5Y, 5Y, or 5GY matrix; 10YR or 2.5Y redox Hue: 10YR or 2.5Y concentrations Value: 4 or 5 dry; 2 or 3 moist Value: 6 or 7 matrix, 5 or 6 redox concentrations Chroma: 1 or 2 dry; 4 to 6 matrix, 4 or 5 redox concentrations Texture (less than 2 mm): Clay loam moist Clay content: 27 to 40 percent Chroma: 1 or 2 matrix; 4, 6, or 8 redox Calcium carbonate equivalent: 1 to 5 percent concentrations Reaction: pH 6.6 to 8.4 Redox concentrations: Common or many; faint to Bw horizon prominent Hue: 10YR, 2.5Y, or 5Y Texture (less than 2 mm): Sandy clay loam with Value: 4 to 6 dry; 3 or 4 moist strata of sandy clay 78 Soil Survey

Clay content: 30 to 45 percent Range in Characteristics Content of rock fragments: 0 to 15 percent gravel Soil temperature: 38 to 42 degrees F Calcium carbonate equivalent: 5 to 10 percent Depth to the Bk horizon: 8 to 15 inches Gypsum content: 1 to 3 percent Electrical conductivity: 2 to 4 mmhos/cm A horizon Reaction: pH 7.9 to 9.0 Hue: 10YR or 2.5Y Value: 5 to 7 dry; 3 or 4 moist Chroma: 2 to 4 Knep Family Texture (less than 2 mm): Loam Clay content: 18 to 27 percent Depth class: Very deep (greater than 60 inches) Content of rock fragments: 0 to 15 percent gravel Drainage class: Well drained Reaction: pH 7.4 to 8.4 Permeability: Moderate (0.6 to 2.0 inches/hour) Bw horizon Landform: Mountain Hue: 10YR or 2.5Y Parent material: Loamy alluvium or colluvium Value: 5 to 7 dry; 4 or 5 moist Slope range: 8 to 15 percent Chroma: 2 to 4 Elevation range: 5,500 to 7,500 feet Texture (less than 2 mm): Loam or sandy clay Mean annual precipitation: 20 to 25 inches loam Mean annual air temperature: 35 to 40 degrees F Clay content: 18 to 30 percent Frost-free period: 50 to 70 days Content of rock fragments: 0 to 15 percent gravel Reaction: pH 7.4 to 8.4 Taxonomic Class: Fine-loamy, mixed, superactive Ustic Eutrocryepts Bk horizon Hue: 10YR, 2.5Y, or 5Y Typical Pedon Value: 5 to 7 dry; 4 to 6 moist Chroma: 2 to 4 Knep loam, in an area of Knep family-Warwood Texture (less than 2 mm): Loam or sandy clay loams, 4 to 15 percent slopes, in an area of loam coniferous forest, 1,400 feet south and 1,800 feet Clay content: 18 to 30 percent west of the northeast corner of sec. 15, T. 2 N., Content of rock fragments: 0 to 15 percent gravel R. 12 E.; USGS Raspberry Butte topographic Calcium carbonate equivalent: 5 to 15 percent quadrangle (lat. 45o55'31" N.; long. 110o13'02" W.) Reaction: pH 7.9 to 9.0 Oi—0 to 2 inches; partially decomposed forest litter. A—2 to 6 inches; light brownish gray (2.5Y 6/2) loam, Knep Series dark grayish brown (2.5Y 4/2) moist; weak thin and medium platy structure parting to moderate Depth class: Moderately deep (20 to 40 inches) fine granular; slightly hard, friable, slightly sticky, Drainage class: Well drained slightly plastic; common very fine to medium Permeability: Moderate (0.6 to 2.0 inches/hour) roots; many very fine to medium pores; slightly Landform: Hill and mountain alkaline (pH 7.4); abrupt smooth boundary. Parent material: Loamy residuum weathered from Bw—6 to 14 inches; light gray (2.5Y 7/2) loam, olive sandstone and siltstone brown (2.5Y 4/4) moist; moderate fine and Slope range: 15 to 45 percent medium prismatic structure; moderately hard, Elevation range: 6,000 to 7,500 feet firm, slightly sticky, slightly plastic; common very Mean annual precipitation: 20 to 25 inches fine to medium roots; slightly effervescent; Mean annual air temperature: 36 to 38 degrees F moderately alkaline (pH 8.2); clear wavy Frost-free period: 50 to 70 days boundary. Bk—14 to 62 inches; light gray (2.5Y 7/2) loam, Taxonomic Class: Fine-loamy, mixed, superactive grayish brown (2.5Y 5/2) moist; weak medium Ustic Eutrocryepts and coarse prismatic structure; moderately hard, Typical Pedon firm, slightly sticky, slightly plastic; few very fine and fine roots; common very fine and fine pores; Knep channery loam, in an area of Fifer-Knep few fine threads and masses of lime; strongly complex, 15 to 45 percent slopes, in an area of effervescent; moderately alkaline (pH 8.4). rangeland, 2,200 feet north and 300 feet east of the Sweet Grass County Area, Montana—Part I 79

southwest corner of sec. 15, T. 2 N., R. 12 E.; USGS Content of rock fragments: 5 to 25 percent gravel Raspberry Butte topographic quadrangle (lat. or channers 45o55'16" N.; long. 110o13'45" W.) Reaction: pH 7.4 to 8.4 A—0 to 7 inches; light brownish gray (2.5Y 6/2) Bk horizon channery loam, dark grayish brown (2.5Y 4/2) Hue: 10YR or 2.5Y moist; moderate very fine and fine granular Value: 6 or 7 dry; 4 or 5 moist structure; soft, friable, nonsticky, nonplastic; Chroma: 2 or 3 common very fine to medium roots; many fine Texture (less than 2 mm): Loam, clay loam, silty pores; strongly effervescent; 30 percent clay loam, or very fine sandy loam channers; slightly alkaline (pH 7.6); clear smooth Clay content: 14 to 35 percent boundary. Content of rock fragments: 5 to 25 percent gravel Bw—7 to 17 inches; light brownish gray (2.5Y 6/2) or channers loam, dark grayish brown (2.5Y 4/2) moist; Reaction: pH 7.4 to 8.4 moderate fine and medium subangular blocky structure; slightly hard, friable, slightly sticky, slightly plastic; few medium and common very Kobase Series fine and fine roots; common very fine and fine Depth class: Very deep (greater than 60 inches) pores; strongly effervescent; 10 percent Drainage class: Well drained channers; slightly alkaline (pH 7.8); abrupt Permeability: Slow (0.06 to 0.20 inch/hour) smooth boundary. Landform: Hill, stream terrace, and swale on plain Bk—17 to 25 inches; light brownish gray (2.5Y 6/2) Parent material: Clayey alluvium weathered from channery loam, dark grayish brown (2.5Y 4/2) shale and siltstone moist; moderate medium subangular blocky Slope range: 2 to 15 percent structure; slightly hard, friable, slightly sticky, Elevation range: 3,750 to 5,200 feet slightly plastic; few very fine and fine roots; Mean annual precipitation: 10 to 14 inches common very fine and fine pores; few soft Mean annual air temperature: 43 to 46 degrees F masses of lime; strongly effervescent; 20 percent Frost-free period: 95 to 125 days channers; moderately alkaline (pH 8.0); clear smooth boundary. Taxonomic Class: Fine, smectitic, frigid Torrertic Cr—25 to 60 inches; calcareous interbedded shale Haplustepts and siltstone. Typical Pedon Range in Characteristics Kobase clay loam, in an area of Kobase clay loam, Soil temperature: 37 to 40 degrees F 2 to 8 percent slopes, in an area of rangeland, Moisture control section: Between 4 and 12 inches 200 feet north and 400 feet east of the southwest Depth to bedrock: 20 to 40 inches corner of sec. 8, T. 3 N., R. 18 E.; USGS Gibson Depth to the Bk horizon: 7 to 20 inches topographic quadrangle (lat. 46o01'09" N.; long. A horizon 109o31'19" W.) Hue: 10YR or 2.5Y A—0 to 7 inches; grayish brown (2.5Y 5/2) clay loam, Value: 4 to 6 dry; 3 to 5 moist dark grayish brown (2.5Y 4/2) moist; weak fine Chroma: 2 or 3 granular structure; soft, friable, moderately sticky, Texture (less than 2 mm): Loam moderately plastic; many very fine and fine roots; Clay content: 20 to 27 percent many very fine and fine pores; strongly Content of rock fragments: 5 to 35 percent gravel effervescent; slightly alkaline (pH 7.8); clear or channers smooth boundary. Reaction: pH 7.4 to 8.4 Bw—7 to 12 inches; grayish brown (2.5Y 5/2) clay Bw horizon loam, dark grayish brown (2.5Y 4/2) moist; weak Hue: 10YR or 2.5Y medium subangular blocky structure; slightly Value: 5 or 6 dry; 4 or 5 moist hard, friable, moderately sticky, moderately Chroma: 2 or 3 plastic; few fine and common very fine roots; Texture (less than 2 mm): Loam, clay loam, silt common very fine and fine pores; strongly loam, or silty clay loam effervescent; moderately alkaline (pH 8.4); clear Clay content: 24 to 32 percent smooth boundary. 80 Soil Survey

Bk1—12 to 19 inches; light brownish gray (2.5Y 6/2) Texture (less than 2 mm): Clay loam, silty clay clay loam, grayish brown (2.5Y 5/2) moist; loam, silty clay, or clay moderate medium subangular blocky structure; Clay content: 35 to 45 percent moderately hard, friable, moderately sticky, Content of rock fragments: 0 to 5 percent gravel moderately plastic; few fine roots; common very Calcium carbonate equivalent: 5 to 15 percent fine and fine pores; many fine threads and soft Sodium adsorption ratio: 5 to 10 masses of lime; violently effervescent; moderately Reaction: pH 7.4 to 9.0 alkaline (pH 8.4); clear smooth boundary. Bk2 horizon Bk2—19 to 35 inches; light brownish gray (2.5Y 6/2) Hue: 10YR, 2.5Y, or 5Y clay loam, grayish brown (2.5Y 5/2) moist; weak Value: 5 to 7 dry; 4 to 6 moist coarse prismatic structure; moderately hard, Chroma: 2 to 4 friable, moderately sticky, moderately plastic; few Texture (less than 2 mm): Clay loam, silty clay fine roots; few very fine and fine pores; common loam, silty clay, or clay fine threads and soft masses of lime; violently Clay content: 35 to 45 percent effervescent; strongly alkaline (pH 8.6); clear Content of rock fragments: 0 to 5 percent gravel smooth boundary. Calcium carbonate equivalent: 5 to 15 percent Bky—35 to 60 inches; light brownish gray (2.5Y 6/2) Sodium adsorption ratio: 5 to 10 clay loam, grayish brown (2.5Y 5/2) moist; weak Reaction: pH 7.9 to 9.0 coarse prismatic structure; moderately hard, firm, moderately sticky, moderately plastic; few fine Bky horizon threads and soft masses of lime; few fine platelike Hue: 10YR, 2.5Y, or 5Y gypsum crystals; violently effervescent; strongly Value: 5 to 7 dry; 4 to 6 moist alkaline (pH 8.6). Chroma: 2 to 4 Texture (less than 2 mm): Clay loam, silty clay Range in Characteristics loam, silty clay, or clay Soil temperature: 42 to 47 degrees F Clay content: 35 to 45 percent Moisture control section: Between 4 and 12 inches Content of rock fragments: 0 to 5 percent gravel Depth to the Bk horizon: 12 to 17 inches Calcium carbonate equivalent: 5 to 15 percent Electrical conductivity: 0 to 4 mmhos/cm A horizon Sodium adsorption ratio: 8 to 13 Hue: 10YR or 2.5Y Gypsum content: 1 to 5 percent Value: 5 or 6 dry; 4 or 5 moist Reaction: pH 7.9 to 9.0 Chroma: 2 or 3 Texture (less than 2 mm): Clay loam Clay content: 27 to 40 percent Korchea Series Calcium carbonate equivalent: 0 to 5 percent Content of rock fragments: 0 to 5 percent gravel Depth class: Very deep (greater than 60 inches) Sodium adsorption ratio: 1 to 4 Drainage class: Well drained Reaction: pH 6.6 to 8.4 Permeability: Moderate (0.6 to 2.0 inches/hour) Landform: Flood plain, flood-plain step, stream Bw horizon terrace, and drainageway on plain Hue: 10YR or 2.5Y Parent material: Loamy alluvium Value: 5 or 6 dry; 4 or 5 moist Slope range: 0 to 4 percent Chroma: 2 to 4 Elevation range: 3,750 to 6,200 feet Texture (less than 2 mm): Clay loam, silty clay Mean annual precipitation: 10 to 20 inches loam, silty clay, or clay Mean annual air temperature: 39 to 46 degrees F Clay content: 35 to 45 percent Frost-free period: 70 to 130 days Content of rock fragments: 0 to 5 percent gravel Calcium carbonate equivalent: 0 to 10 percent Taxonomic Class: Fine-loamy, mixed, superactive, Sodium adsorption ratio: 1 to 4 calcareous, frigid Mollic Ustifluvents Reaction: pH 7.4 to 8.4 Typical Pedon Bk1 horizon Hue: 10YR, 2.5Y, or 5Y Korchea loam, in an area of Korchea loam, 0 to Value: 5 to 7 dry; 4 to 6 moist 2 percent slopes, in an area of cropland, 1,400 feet Chroma: 2 to 4 north and 1,800 feet west of the southeast corner of Sweet Grass County Area, Montana—Part I 81

sec. 29, T. 3 N., R. 15 E.; USGS Otter Creek School Content of rock fragments: 0 to 5 percent gravel topographic quadrangle (lat. 45o58'38" N.; long. Calcium carbonate equivalent: 1 to 5 percent 109o52'57" W.) Reaction: pH 6.6 to 8.4 Ap—0 to 5 inches; grayish brown (10YR 5/2) loam, C horizons very dark grayish brown (10YR 3/2) moist; Hue: 10YR, 2.5Y, or 5Y moderate medium platy structure parting to Value: 4 to 7 dry; 3 to 6 moist moderate fine granular; soft, very friable, slightly Chroma: 2 to 4 sticky, slightly plastic; common very fine roots; Texture (less than 2 mm): Stratified loam, fine common very fine pores; slightly effervescent; sandy loam, silt loam, silty clay loam, sandy slightly alkaline (pH 7.6); abrupt smooth loam, or very fine sandy loam boundary. Clay content: 18 to 35 percent C1—5 to 12 inches; light brownish gray (2.5Y 6/2) Content of rock fragments: 0 to 5 percent gravel stratified loam, dark grayish brown (2.5Y 4/2) Calcium carbonate equivalent: 5 to 10 percent moist; moderate medium angular blocky Electrical conductivity: 0 to 4 mmhos/cm structure; moderately hard, firm, slightly sticky, Reaction: pH 7.4 to 9.0 slightly plastic; common very fine roots; common very fine pores; strongly effervescent; moderately alkaline (pH 8.4); abrupt wavy boundary. Kremlin Series C2—12 to 22 inches; light brownish gray (2.5Y 6/2) stratified loam, dark grayish brown (2.5Y 4/2) Depth class: Very deep (greater than 60 inches) moist; moderate fine subangular blocky structure; Drainage class: Well drained moderately hard, friable, slightly sticky, slightly Permeability: Moderate (0.6 to 2.0 inches/hour) plastic; common very fine roots; common very Landform: Fan, stream terrace, terrace, swale on fan, fine pores; strongly effervescent; slightly alkaline and swale on plain (pH 7.8); abrupt smooth boundary. Parent material: Loamy alluvium C3—22 to 34 inches; light brownish gray (2.5Y 6/2) Slope range: 0 to 15 percent stratified very fine sandy loam and loam, grayish Elevation range: 3,750 to 5,200 feet brown (2.5Y 5/2) moist; massive; slightly hard, Mean annual precipitation: 10 to 14 inches friable, slightly sticky, slightly plastic; common Mean annual air temperature: 43 to 46 degrees F very fine roots; many very fine pores; strongly Frost-free period: 95 to 125 days effervescent; moderately alkaline (pH 8.2); abrupt smooth boundary. Taxonomic Class: Fine-loamy, mixed, superactive, C4—34 to 60 inches; grayish brown (2.5Y 5/2) frigid Aridic Haplustolls stratified loam and very fine sandy loam, dark Typical Pedon grayish brown (2.5Y 4/2) moist; massive; slightly hard, very friable, slightly sticky, slightly plastic; Kremlin loam, 1,000 feet south and 1,700 feet east few very fine and fine roots; few very fine and fine of the northwest corner of sec. 23, T. 30 N., R. 10 E.; pores; strongly effervescent; moderately alkaline Hill County, Montana. (pH 8.2). Ap—0 to 6 inches; grayish brown (10YR 5/2) loam, Range in Characteristics very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; soft, very Soil temperature: 42 to 47 degrees F friable, moderately sticky, moderately plastic; Moisture control section: Between 4 and 12 inches many very fine and fine roots; neutral (pH 6.8); Thickness of the mollic epipedon: 5 to 15 inches abrupt smooth boundary. Notes: The C horizons are stratified with finer and A2—6 to 11 inches; dark grayish brown (2.5Y 4/2) coarser materials. loam, very dark grayish brown (2.5Y 3/2) moist; A horizon moderate medium prismatic structure parting to Hue: 10YR or 2.5Y moderate fine and medium subangular blocky; Value: 4 or 5 dry; 2 or 3 moist slightly hard, very friable, moderately sticky, Chroma: 2 or 3 moderately plastic; many very fine roots; many Texture (less than 2 mm): Loam very fine pores; neutral (pH 6.8); clear smooth Clay content: 18 to 27 percent boundary. 82 Soil Survey

Bw—11 to 19 inches; grayish brown (2.5Y 5/2) loam, Calcium carbonate equivalent: 5 to 15 percent dark grayish brown (2.5Y 4/2) moist; weak Reaction: pH 7.0 to 8.4 medium subangular blocky structure; slightly Bk1 horizon hard, friable, moderately sticky, moderately Hue: 10YR or 2.5Y plastic; many very fine roots; many very fine Value: 5 to 7 dry; 4 to 6 moist pores; neutral (pH 7.0); clear smooth boundary. Chroma: 2 to 4 Bk1—19 to 31 inches; light brownish gray (2.5Y 6/2) Texture (less than 2 mm): Loam, silt loam, clay loam, dark grayish brown (2.5Y 4/4) moist; weak loam, or sandy clay loam fine subangular blocky structure; hard, friable, Clay content: 18 to 32 percent moderately sticky, moderately plastic; many very Content of rock fragments: 0 to 5 percent gravel fine roots; many very fine pores; few fine masses Calcium carbonate equivalent: 5 to 15 percent of lime; strongly effervescent; moderately alkaline Reaction: pH 7.4 to 8.4 (pH 8.4); clear smooth boundary. Bk2—31 to 60 inches; light yellowish brown (2.5Y Bk2 horizon 6/4) loam, grayish brown (2.5Y 5/2) moist; weak Hue: 10YR, 2.5Y, or 5Y fine subangular blocky structure; hard, friable, Value: 6 to 8 dry; 4 to 6 moist moderately sticky, moderately plastic; common Chroma: 2 to 4 very fine roots; common very fine pores; common Texture (less than 2 mm): Stratified loam, silt fine masses of lime; violently effervescent; loam, clay loam, or sandy clay loam moderately alkaline (pH 8.2). Clay content: 18 to 30 percent Content of rock fragments: 0 to 5 percent gravel Range in Characteristics Calcium carbonate equivalent: 3 to 12 percent Soil temperature: 41 to 47 degrees F Reaction: pH 7.4 to 8.4 Moisture control section: Between 4 and 12 inches Thickness of the mollic epipedon: 7 to 12 inches Depth to the Bk horizon: 10 to 24 inches Laceycreek Series Ap horizon Depth class: Very deep (greater than 60 inches) Hue: 10YR or 2.5Y Drainage class: Well drained Value: 2 or 3 moist Permeability: Moderate (0.6 to 2.0 inches/hour) Chroma: 2 or 3 Landform: Drainageway on escarpment, swale on Texture (less than 2 mm): Loam or clay loam escarpment, drainageway on hill, swale on hill, Clay content: 18 to 32 percent drainageway on stream terrace, and swale on Content of rock fragments: 0 to 5 percent gravel stream terrace Calcium carbonate equivalent: 0 to 10 percent Parent material: Loamy alluvium Reaction: pH 6.1 to 8.4 Slope range: 2 to 45 percent Elevation range: 4,200 to 6,200 feet A2 horizon Mean annual precipitation: 15 to 20 inches Hue: 10YR or 2.5Y Mean annual air temperature: 39 to 45 degrees F Value: 4 or 5 dry; 3 or 4 moist Frost-free period: 70 to 115 days Chroma: 2 or 3 Texture (less than 2 mm): Loam, silt loam, clay Taxonomic Class: Fine-loamy, mixed, superactive, loam, or sandy clay loam frigid Pachic Argiustolls Clay content: 18 to 32 percent Content of rock fragments: 0 to 5 percent gravel Typical Pedon Calcium carbonate equivalent: 0 to 10 percent Reaction: pH 6.6 to 8.4 Laceycreek loam, in an area of Castner-Laceycreek- Bowery complex, 25 to 60 percent slopes, in an area Bw horizon of rangeland, 1,200 feet south and 1,000 feet east Hue: 10YR or 2.5Y of the northwest corner of sec. 24, T. 2 S., R. 13 E.; Value: 4 to 6 dry; 3 to 5 moist USGS McLeod topographic quadrangle (lat. Chroma: 2 to 4 45o39'04" N.; long. 110o04'11" W.) Texture (less than 2 mm): Loam, silt loam, clay loam, or sandy clay loam A1—0 to 4 inches; very dark gray (10YR 3/1) sandy Clay content: 18 to 32 percent loam, black (10YR 2/1) moist; moderate fine and Content of rock fragments: 0 to 5 percent gravel medium granular structure; soft, very friable, Sweet Grass County Area, Montana—Part I 83

slightly sticky, slightly plastic; common medium Texture (less than 2 mm): Loam or sandy loam and many very fine and fine roots; common very Clay content: 10 to 24 percent fine and fine pores; neutral (pH 7.0); clear wavy Content of rock fragments: 0 to 15 percent—0 to boundary. 5 percent cobbles; 0 to 10 percent gravel A2—4 to 12 inches; dark gray (10YR 4/1) loam, very Reaction: pH 6.1 to 7.3 dark gray (10YR 3/1) moist; weak medium A2 and A3 horizon subangular blocky structure parting to moderate Hue: 10YR, 2.5Y, or N fine granular; slightly hard, friable, slightly sticky, Value: 3 or 4 dry; 2 or 3 moist slightly plastic; common very fine and fine Chroma: 1 to 3 roots; common very fine and fine pores; neutral Texture (less than 2 mm): Loam or very fine (pH 7.0); clear wavy boundary. sandy loam A3—12 to 23 inches; dark grayish brown (10YR 4/2) Clay content: 15 to 24 percent loam, dark brown (10YR 3/3) dry; moderate Content of rock fragments: 0 to 15 percent—0 to medium subangular blocky structure; slightly 5 percent cobbles; 0 to 10 percent gravel hard, friable, slightly sticky, slightly plastic; few Reaction: pH 6.1 to 7.3 very fine and fine roots; common very fine and fine pores; neutral (pH 7.0); gradual wavy Bt1 horizon boundary. Hue: 10YR or 2.5Y Bt1—23 to 32 inches; brown (10YR 5/3) clay loam, Value: 3 to 5 dry; 3 or 4 moist dark yellowish brown (10YR 4/4) moist; moderate Chroma: 2 to 4 medium and coarse subangular blocky structure; Texture (less than 2 mm): Loam or clay loam hard, very firm, moderately sticky, moderately Clay content: 24 to 35 percent plastic; few very fine roots; few very fine and fine Content of rock fragments: 0 to 10 percent—0 to pores; few distinct discontinuous dark grayish 5 percent cobbles; 0 to 5 percent gravel brown (10YR 4/3) moist; clay films on faces of Reaction: pH 6.1 to 7.3 peds and lining pores; neutral (pH 7.2); clear Bt2 horizon wavy boundary. Hue: 10YR or 2.5Y Bt2—32 to 58 inches; yellowish brown (10YR 5/4) Value: 4 or 5 dry; 3 or 4 moist gravelly clay loam, dark yellowish brown (10YR Chroma: 2 to 4 3/4) moist; moderate medium and coarse Texture (less than 2 mm): Loam, clay loam, or subangular blocky structure; hard, very firm, sandy clay loam moderately sticky, moderately plastic; few very Clay content: 20 to 35 percent fine roots; few very fine and fine pores; common Content of rock fragments: 0 to 25 percent—0 to distinct discontinuous dark brown (10YR 3/3) 5 percent cobbles; 0 to 20 percent gravel moist; clay films on faces of peds and lining Reaction: pH 6.6 to 7.3 pores; 20 percent gravel; slightly alkaline (pH 7.4); clear smooth boundary. 2BC horizon 2BC—58 to 60 inches; yellowish brown (10YR 5/4) Hue: 10YR or 2.5Y very channery sandy loam, dark yellowish brown Value: 4 to 6 dry; 3 to 5 moist (10YR 3/4) moist; weak medium subangular Chroma: 2 to 4 blocky structure; soft, very friable, nonsticky, Texture (less than 2 mm): Sandy loam or loam nonplastic; 35 percent channers; 10 percent Clay content: 5 to 20 percent flagstones; slightly alkaline (pH 7.4). Content of rock fragments: 15 to 60 percent—0 to 10 percent flagstones or cobbles; 15 to Range in Characteristics 50 percent gravel or channers Soil temperature: 40 to 43 degrees F Calcium carbonate equivalent: 0 to 2 percent Moisture control section: Between 4 and 12 inches Reaction: pH 6.6 to 7.3 Thickness of the mollic epipedon: 16 to 60 inches Depth to the BC horizon: 40 inches or more Note: Some pedons do not have a 2BC horizon. Lallie Family A1 horizon Depth class: Very deep (greater than 60 inches) Hue: 10YR, 2.5Y, or N Drainage class: Poorly drained Value: 3 or 4 dry; 2 or 3 moist Permeability: Slow (0.06 to 0.20 inch/hour) Chroma: 0 or 1 Landform: Flood plain and depression on flood plain 84 Soil Survey

Parent material: Clayey alluvium Range in Characteristics Slope range: 0 to 2 percent Soil temperature: 36 to 47 degrees F Elevation range: 3,750 to 6,200 feet Moisture control section: Between 4 and 12 inches Mean annual precipitation: 10 to 20 inches Depth to the seasonal high water table: 0 to Mean annual air temperature: 39 to 46 degrees F 12 inches Frost-free period: 70 to 125 days A horizon Taxonomic Class: Fine, smectitic, calcareous, frigid Hue: 10YR, 2.5Y, or 5Y Vertic Fluvaquents Value: 2 to 4 moist; 3 to 6 dry Chroma: 1 or 2 Typical Pedon Texture (less than 2 mm): Silty clay Clay content: 40 to 60 percent Lallie silty clay loam, in an area of grassland, 150 feet Calcium carbonate equivalent: 5 to 10 percent south and 600 feet west of the northeast corner sec. Gypsum content: 0 to 1 percent 35, T. 21 N., R. 1 W.; Cascade County, Montana. Electrical conductivity: 0 to 8 mmhos/cm Reaction: pH 6.6 to 9.0 A—0 to 2 inches; grayish brown (10YR 5/2) silty clay, very dark grayish brown (10YR 3/2) moist; Cg horizons moderate medium granular structure; extremely Hue: 2.5Y, 5Y, or N hard, friable, moderately sticky, moderately Value: 3 to 6 moist; 4 to 8 dry plastic; many very fine and fine roots; slightly Chroma: 0 to 2 effervescent; strongly alkaline (pH 8.5); gradual Texture (less than 2 mm): Silty clay loam or silty wavy boundary. clay with strata of silt loam Cg1—2 to 12 inches; gray (N 6/) silty clay, gray, (N 5/) Clay content: 35 to 60 percent moist; common fine to medium prominent dark Calcium carbonate equivalent: 5 to 10 percent yellowish brown (10YR 4/4) moist, mottles; strong Gypsum content: 0 to 5 percent very fine subangular blocky structure; extremely Electrical conductivity: 0 to 8 mmhos/cm hard, firm, moderately sticky, very plastic; Reaction: pH 7.4 to 9.0 common very fine and fine roots; many very fine 2Cg horizon and fine pores; many very fine masses of Hue: 2.5Y or 5Y gypsum; strongly effervescent; moderately Value: 4 to 6 moist; 5 to 8 dry alkaline (pH 8.2); gradual wavy boundary. Chroma: 1 or 2 Cg2—12 to 45 inches; light gray (N 7/) silty clay, gray Texture (less than 2 mm): Sand, coarse sand, or (N 5/) and greenish gray (5GY 6/1) moist; many loamy sand fine to coarse prominent olive brown (2.5Y 4/4) Clay content: 0 to 10 percent moist, mottles; massive; extremely hard, firm, Content of rock fragments: 35 to 55 percent—0 to moderately sticky, very plastic; common very 10 percent cobbles; 35 to 45 percent gravel fine and fine roots; many very fine and fine Calcium carbonate equivalent: 5 to 10 percent pores; strongly effervescent; moderately alkaline Reaction: pH 7.4 to 9.0 (pH 8.2); gradual smooth boundary. Cg3—45 to 50 inches; gray (N 6/) clay loam, gray (N 5/) moist; few fine and medium distinct dark Lap Series gray (N 1/) moist, mottles; massive; extremely hard, friable, moderately sticky, moderately Depth class: Shallow (10 to 20 inches) plastic; few very fine and fine roots; common Drainage class: Well drained very fine and fine pores; strongly effervescent; Permeability: Moderate (0.6 to 2.0 inches/hour) moderately alkaline (pH 8.2); gradual wavy Landform: Hill and mountain boundary. Parent material: Residuum weathered from limestone 2Cg4—50 to 60 inches; light gray (5Y 6/1) very Slope range: 8 to 70 percent gravelly sand, dark gray (5Y 4/1) moist; single Elevation range: 5,300 to 6,200 feet grain; loose, nonsticky, nonplastic; strongly Mean annual precipitation: 17 to 20 inches effervescent; 40 percent gravel; 5 percent Mean annual air temperature: 39 to 42 degrees F cobbles; moderately alkaline (pH 8.2). Frost-free period: 70 to 90 days Sweet Grass County Area, Montana—Part I 85

Taxonomic Class: Loamy-skeletal, carbonatic, frigid Calcium carbonate equivalent: 0 to 15 percent in Lithic Calciustolls the less than 2-mm particle size class and more than 40 percent in the less than 20-mm Typical Pedon particle size class Lap channery loam, in an area of Lap-Winspect-Rock Reaction: pH 6.6 to 7.8 outcrop complex, 8 to 35 percent slopes, in an area Bk horizon of rangeland, 300 feet north and 600 feet west of Hue: 7.5YR, 10YR, or 2.5Y the southeast corner of sec. 23, T. 3 S., R. 12 E.; Value: 5 to 8 dry; 4 to 6 moist USGS McLeod Basin topographic quadrangle (lat. Chroma: 2 or 3 45o33'12" N.; long. 110o11'58" W.) Texture (less than 2 mm): Loam or clay loam A1—0 to 4 inches; dark grayish brown (10YR 4/2) Clay content: 20 to 30 percent channery loam, very dark brown (10YR 2/2) Content of rock fragments: 35 to 70 percent—0 to moist; weak fine granular structure; soft, very 30 percent stones, flagstones, or cobbles; friable, slightly sticky, nonplastic; many very fine 35 to 55 percent gravel or channers and fine roots; many very fine and fine pores; Calcium carbonate equivalent: 40 to 60 percent in 20 percent angular channers; strongly the less than 2-mm particle size class and effervescent; moderately alkaline (pH 8.4); clear more than 40 percent in the less than 20-mm smooth boundary. particle size class. A2—4 to 8 inches; brown (10YR 4/3) very channery Reaction: pH 7.9 to 8.4 loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure; soft, very friable, slightly sticky, nonplastic; many very Larry Series fine and fine roots; many very fine and fine pores; Depth class: Very deep (greater than 60 inches) 35 percent channers; 5 percent cobbles; strongly Drainage class: Poorly drained effervescent; moderately alkaline (pH 8.4); abrupt Permeability: Moderately slow (0.2 to 0.6 inch/hour) smooth boundary. Landform: Flood plain and flood-plain step Bk—8 to 14 inches; light brownish gray (10YR 6/2) Parent material: Loamy alluvium very channery loam, grayish brown (10YR 5/2) Slope range: 0 to 4 percent moist; weak fine and medium granular structure; Elevation range: 3,750 to 6,200 feet slightly hard, friable, slightly sticky, slightly plastic; Mean annual precipitation: 10 to 20 inches common very fine and fine roots; many very fine Mean annual air temperature: 39 to 46 degrees F and fine pores; 40 percent channers; 15 percent Frost-free period: 70 to 130 days cobbles; lime casts on undersides of channers and cobbles; violently effervescent; strongly Taxonomic Class: Fine-loamy, mixed, superactive, alkaline (pH 8.6); abrupt smooth boundary. frigid Typic Endoaquolls R—14 inches; hard limestone bedrock with some cracks. Typical Pedon Larry clay loam, in an area of Larry clay loam, 0 to Range in Characteristics 2 percent slopes, in an area of tame pasture, 700 feet Soil temperature: 38 to 47 degrees F north and 1,800 feet east of the southwest corner of Moisture control section: Between 4 and 12 inches sec. 29, T. 2 N., R. 14 E.; USGS Grosfield Ranch Thickness of the mollic epipedon: 7 to 12 inches topographic quadrangle (lat. 45o53'19" N.; long. Depth to bedrock: 10 to 20 inches 110o00'50" W.) A horizons A—0 to 7 inches; gray (5Y 5/1) clay loam, very dark Hue: 10YR or 2.5Y gray (5Y 3/1) moist; moderate very fine granular Value: 3 to 5 dry; 2 or 3 moist structure; extremely hard, friable, moderately Chroma: 1 to 3 sticky, moderately plastic; few medium and Texture (less than 2 mm): Loam coarse and many very fine and fine roots; Clay content: 15 to 25 percent common very fine and fine pores; slightly alkaline Content of rock fragments: 10 to 60 percent—0 to (pH 7.4); clear wavy boundary. 20 percent stones, flagstones, or cobbles; Bg—7 to 15 inches; gray (5Y 6/1) clay loam, gray 10 to 40 percent gravel or channers (5Y 5/1) moist; few fine prominent yellowish 86 Soil Survey

brown (10YR 5/4) moist, redox concentrations; Bg horizon weak fine granular structure; extremely hard, Hue: 5Y or N friable, moderately sticky, moderately plastic; Value: 4 to 6 dry; 3 to 6 moist few fine and medium and common very fine Chroma: 0 to 2 roots; common very fine and fine pores; strongly Redox concentrations: None to common; chroma effervescent; moderately alkaline (pH 8.4); of 4 or 6 gradual wavy boundary. Texture (less than 2 mm): Clay loam, silt loam, or Cg1—15 to 31 inches; light gray (5Y 7/1) clay loam, loam gray (5Y 6/1) moist; few fine prominent yellowish Clay content: 20 to 35 percent brown (10YR 5/4) moist, redox concentrations; Content of rock fragments: 0 to 15 percent gravel massive; extremely hard, friable, moderately Calcium carbonate equivalent: 1 to 15 percent sticky, moderately plastic; few very fine to Reaction: pH 6.6 to 8.4 medium roots; common very fine and fine pores; Cg1 horizon disseminated lime; strongly effervescent; Hue: 10YR, 2.5Y, 5Y, or N moderately alkaline (pH 8.4); clear wavy Value: 5 to dry; 5 or 6 moist boundary. Chroma: 0 to 2 Cg2—31 to 36 inches; light olive gray (5Y 6/2) Redox concentrations: Few to many; chroma of 4 gravelly loam, olive gray (5Y 5/2) moist; few fine or 6 prominent yellowish brown (10YR 5/4) moist, Redox depletions: None to common; chroma of 0 redox concentrations; massive; extremely hard, or 1 friable, moderately sticky, moderately plastic; few Texture (less than 2 mm): Clay loam, silt loam, or very fine roots; common very fine and fine pores; loam with strata of sandy loam 15 percent gravel; strongly effervescent; Clay content: 20 to 35 percent moderately alkaline (pH 8.4); clear wavy Content of rock fragments: 0 to 15 percent gravel boundary. Calcium carbonate equivalent: 1 to 15 percent Cg3—36 to 44 inches; light olive gray (5Y 6/2) Reaction: pH 6.6 to 8.4 gravelly sandy loam, olive gray (5Y 5/2) moist; massive; extremely hard, friable, moderately Cg2 and Cg3 horizons sticky, moderately plastic; few very fine roots; Hue: 5Y, 2.5Y, or N common very fine and fine pores; 20 percent Value: 5 to 7 dry; 4 to 6 moist gravel; strongly effervescent; moderately alkaline Chroma: 0 to 2 (pH 8.4); clear wavy boundary. Redox concentrations: None to many; chroma of Cg4—44 to 60 inches; light olive gray (5Y 6/2) clay 4 or 6 loam, olive gray (5Y 4/2) moist; few medium Redox depletions: None to common; chroma of 0 prominent gray (N 6/) moist, redox depletions; or 1 massive; extremely hard, extremely firm, very Texture (less than 2 mm): Clay loam, silt loam, or sticky, very plastic; few very fine pores; strongly loam with strata of sandy loam effervescent; moderately alkaline (pH 8.2). Clay content: 20 to 35 percent Content of rock fragments: 0 to 35 percent—0 to Range in Characteristics 10 percent cobbles; 0 to 25 percent gravel Soil temperature: 42 to 46 degrees F Calcium carbonate equivalent: 1 to 15 percent Moisture control section: Between 4 and 12 inches Reaction: pH 6.6 to 8.4 Thickness of the mollic epipedon: 7 to 18 inches Cg4 horizon Depth to the seasonal high water table: +6 to Hue: 5Y, 2.5Y, or N 24 inches Value: 5 to 7 dry; 4 to 6 moist Note: Some pedons do not have a Cg4 horizon. Chroma: 0 to 2 A horizon Redox concentrations: None to many; chroma of Hue: 5Y or N 4 or 6 Value: 3 to 5 dry; 2 or 3 moist Redox depletions: None to common; chroma of 0 Chroma: 0 or 1 or 1 Texture (less than 2 mm): Clay loam or loam Texture (less than 2 mm): Clay loam or clay Clay content: 18 to 35 percent Clay content: 28 to 40 percent Content of rock fragments: 0 to 15 percent gravel Content of rock fragments: 0 to 35 percent—0 to Reaction: pH 6.1 to 7.8 10 percent cobbles; 0 to 25 percent gravel Sweet Grass County Area, Montana—Part I 87

Calcium carbonate equivalent: 1 to 15 percent plastic; common very fine and fine roots; common Reaction: pH 7.4 to 8.4 very fine and fine pores; common very fine masses of salt; strongly effervescent; strongly alkaline (pH 8.8); clear smooth boundary. Ledger Family Cgz1—22 to 41 inches; light brownish gray (2.5Y 6/2) clay, grayish brown (2.5Y 5/2) moist; common fine Depth class: Very deep (greater than 60 inches) faint yellowish brown (10YR 5/4) moist, redox Drainage class: Somewhat poorly drained concentrations; massive; very hard, firm, very Permeability: Slow (0.06 to 0.20 inch/hour) sticky, very plastic; few very fine and fine roots; Landform: Flood plain few very fine and fine pores; few very fine masses Parent material: Clayey alluvium of salt; strongly effervescent; strongly alkaline Slope range: 0 to 4 percent (pH 8.8); gradual smooth boundary. Elevation range: 3,750 to 5,200 feet Cgz2—41 to 60 inches; light brownish gray (2.5Y 6/2) Mean annual precipitation: 10 to 14 inches silty clay loam, grayish brown (2.5Y 5/2) moist; Mean annual air temperature: 43 to 46 degrees F common fine distinct brown (7.5YR 5/4) moist, Frost-free period: 95 to 125 days redox concentrations; massive; moderately hard, firm, very sticky, very plastic; few very fine Taxonomic Class: Fine, mixed, superactive, masses of salt; strongly effervescent; very calcareous, frigid Oxyaquic Ustifluvents strongly alkaline (pH 9.6). Typical Pedon Range in Characteristics Ledger clay loam, in an area of Ledger family clay loam, 1 to 4 percent slopes, in an area of Soil temperature: 42 to 47 degrees F rangeland, 1,500 feet north and 1,300 feet west of Moisture control section: Between 4 and 12 inches the southeast corner of sec. 18, T. 4 N., R. 16 E.; Depth to the seasonal high water table: 24 to USGS Upper Glasston Lake topographic quadrangle 42 inches (lat. 46o05'35" N.; long. 109o46'34" W.) Az horizon Az—0 to 6 inches; grayish brown (10YR 5/2) clay Hue: 10YR or 2.5Y loam, dark grayish brown (10YR 4/2) moist; Value: 4 to 6 dry; 4 or 5 moist moderate medium granular structure; moderately Chroma: 2 or 3 hard, friable, moderately sticky, moderately Texture (less than 2 mm): Clay loam plastic; many very fine and fine roots; many very Clay content: 30 to 40 percent fine and fine pores; few very fine masses of salt; Content of rock fragments: 0 to 5 percent gravel moderately alkaline (pH 8.2); abrupt smooth Calcium carbonate equivalent: 1 to 7 percent boundary. Electrical conductivity: 2 to 8 mmhos/cm ACz—6 to 11 inches; grayish brown (10YR 5/2) clay Sodium adsorption ratio: 0 to 8 loam, dark grayish brown (10YR 4/2) moist; Reaction: pH 7.4 to 8.4 strong fine and medium angular blocky structure; Cz horizons moderately hard, firm, moderately sticky, Hue: 10YR, 2.5Y, or 5Y moderately plastic; many very fine and fine roots; Value: 4 to 7 dry; 4 or 5 moist many very fine and fine pores; few very fine Chroma: 2 or 3 masses of salt; strongly effervescent; moderately Texture (less than 2 mm): Clay loam, silty clay alkaline (pH 8.2); clear smooth boundary. loam, silty clay, or clay consisting of stratified Cz1—11 to 15 inches; grayish brown (10YR 5/2) silty layers clay, dark grayish brown (10YR 4/2) moist; strong Clay content: 35 to 55 percent fine and medium angular blocky structure; very Content of rock fragments: 0 to 5 percent gravel hard, very firm, very sticky, very plastic; many Calcium carbonate equivalent: 5 to 10 percent very fine and fine roots; common very fine and Electrical conductivity: 2 to 16 mmhos/cm fine pores; common very fine masses of salt; Sodium adsorption ratio: 1 to 30 strongly effervescent; strongly alkaline (pH 8.6); Reaction: pH 7.4 to 9.0 clear smooth boundary. Cz2—15 to 22 inches; light brownish gray (2.5Y 6/2) Cgz horizons clay loam, grayish brown (2.5Y 5/2) moist; Hue: 10YR, 2.5Y, or 5Y massive; moderately hard, firm, very sticky, very Value: 4 to 7 dry; 4 or 5 moist 88 Soil Survey

Chroma: 2 or 3 Bt2—15 to 25 inches; brown (10YR 5/3) very gravelly Texture (less than 2 mm): Loam, silty clay loam, loam, brown (10YR 4/3) moist; weak medium and silt loam, or fine sandy loam coarse subangular blocky structure; soft, friable, Clay content: 15 to 35 percent moderately sticky, moderately plastic; common Content of rock fragments: 0 to 5 percent gravel very fine and fine roots; common very fine and Calcium carbonate equivalent: 5 to 10 percent fine pores; few faint patchy brown (7.5YR 4/4) Electrical conductivity: 4 to 16 mmhos/cm moist; clay films on faces of peds; 40 percent Sodium adsorption ratio: 5 to 30 gravel; 15 percent cobbles; neutral (pH 7.0); Reaction: pH 7.9 to 9.6 gradual wavy boundary. Bt3—25 to 35 inches; pale brown (10YR 6/3) very gravelly loam, brown (10YR 5/3) moist; weak Libeg Series medium and coarse subangular blocky structure; soft, friable, moderately sticky, moderately plastic; Depth class: Very deep (greater than 60 inches) few very fine roots; common very fine and fine Drainage class: Well drained pores; few faint patchy brown (7.5YR 5/4) moist; Permeability: Moderate (0.6 to 2.0 inches/hour) clay films on faces of peds; 40 percent gravel; Landform: Fan, landslide, mountain, outwash plain, 15 percent cobbles; neutral (pH 7.0); gradual stream terrace, and terrace wavy boundary. Parent material: Gravelly alluvium or gravelly till BC—35 to 60 inches; light brownish gray (10YR 6/2) Slope range: 12 to 60 percent very gravelly sandy loam, brown (10YR 5/3) Elevation range: 5,500 to 7,500 feet moist; weak coarse subangular blocky structure; Mean annual precipitation: 20 to 25 inches soft, friable, moderately sticky, moderately plastic; Mean annual air temperature: 36 to 38 degrees F common very fine and fine pores; 40 percent Frost-free period: 50 to 70 days gravel; 15 percent cobbles; neutral (pH 6.8). Range in Characteristics Taxonomic Class: Loamy-skeletal, mixed, superactive Ustic Argicryolls Soil temperature: 36 to 44 degrees F Moisture control section: Between 4 and 12 inches Typical Pedon Thickness of the mollic epipedon: 7 to 15 inches A horizon Libeg very cobbly sandy loam, in an area of Libeg Hue: 7.5YR or 10YR very cobbly sandy loam, 2 to 15 percent slopes, in an Value: 3 to 5 dry; 2 or 3 moist area of rangeland, 1,800 feet north and 1,600 feet Chroma: 1 or 2 west of the southeast corner of sec. 1, T. 4 N., Texture (less than 2 mm): Sandy loam or loam R. 12 E.; USGS Amelong Creek topographic Clay content: 5 to 35 percent quadrangle (lat. 46o07'27" N.; long. 110o10'24" W.) Content of rock fragments: 15 to 60 percent—5 to A—0 to 6 inches; very dark grayish brown (10YR 3/2) 50 percent stones and cobbles; 10 to very cobbly sandy loam, black (10YR 2/1) moist; 50 percent gravel moderate fine granular structure; soft, friable, Reaction: pH 6.6 to 7.3 nonsticky, nonplastic; common medium and many Bt1 and Bt2 horizons very fine and fine roots; many very fine and fine Hue: 5YR, 7.5YR, or 10YR pores; 20 percent gravel; 20 percent cobbles; Value: 4 to 6 dry; 3 to 5 moist 5 percent stones; neutral (pH 7.2); clear wavy Chroma: 2 to 4, or 6 boundary. Texture (less than 2 mm): Loam, clay loam, or Bt1—6 to 15 inches; dark yellowish brown (10YR 4/4) sandy loam very gravelly loam, dark brown (10YR 3/3) moist; Clay content: 15 to 35 percent weak fine and medium subangular blocky Content of rock fragments: 35 to 80 percent— structure; soft, friable, moderately sticky, 10 to 50 percent stones and cobbles; 25 to moderately plastic; common fine and medium 45 percent gravel and many very fine roots; common very fine and Reaction: pH 6.6 to 7.3 fine pores; few distinct discontinuous dark brown (7.5YR 3/4) moist; clay films on faces of peds; Bt3 horizon 30 percent gravel; 15 percent cobbles; neutral Hue: 5YR, 7.5YR, or 10YR (pH 7.0); gradual wavy boundary. Value: 5 or 6 dry; 4 or 5 moist Sweet Grass County Area, Montana—Part I 89

Chroma: 3, 4, or 6 moderate fine and medium subangular blocky; Texture (less than 2 mm): Loam or sandy clay hard, friable, moderately sticky, moderately loam plastic; few medium and coarse and many very Clay content: 15 to 27 percent fine and fine roots; few medium and many very Content of rock fragments: 35 to 85 percent—5 to fine and fine pores; few worm casts; slightly 35 percent stones and cobbles; 30 to effervescent; slightly alkaline (pH 7.6); clear wavy 50 percent gravel boundary. Reaction: pH 6.1 to 7.3 Bk1—11 to 15 inches; grayish brown (2.5Y 5/2) silty clay loam, dark grayish brown (2.5Y 4/2) moist; BC horizon moderate medium prismatic structure parting to Hue: 5YR, 7.5YR, or 10YR moderate fine subangular blocky; hard, friable, Value: 5 or 6 dry; 4 or 5 moist moderately sticky, moderately plastic; few Chroma: 2 to 4, or 6 medium and coarse and many very fine and fine Texture (less than 2 mm): Sandy loam or loam roots; few medium and many very fine and fine Clay content: 10 to 25 percent pores; few worm casts; common very fine and Content of rock fragments: 40 to 85 percent— fine masses of lime; strongly effervescent; slightly 10 to 50 percent stones and cobbles; 30 to alkaline (pH 7.8); clear wavy boundary. 50 percent gravel Bk2—15 to 28 inches; light brownish gray (2.5Y 6/2) Reaction: pH 6.6 to 7.8 silty clay loam, dark grayish brown (2.5Y 4/2) moist; moderate medium prismatic structure Linwell Series parting to moderate fine and medium subangular blocky; hard, friable, moderately sticky, Depth class: Very deep (greater than 60 inches) moderately plastic; few medium and coarse and Drainage class: Well drained common very fine and fine roots; few medium Permeability: Slow (0.06 to 0.20 inch/hour) and coarse and many very fine and fine pores; Landform: Fan, stream terrace, terrace, and swale on few worm casts; few medium masses of lime; plain strongly effervescent; moderately alkaline Parent material: Clayey alluvium (pH 7.9); gradual wavy boundary. Slope range: 0 to 35 percent Bk3—28 to 39 inches; light brownish gray (2.5Y 6/2) Elevation range: 4,200 to 6,200 feet silty clay loam, dark grayish brown (2.5Y 4/2) Mean annual precipitation: 15 to 20 inches moist; weak medium prismatic structure; very Mean annual air temperature: 39 to 45 degrees F hard, friable, moderately sticky, moderately Frost-free period: 70 to 115 days plastic; few medium and coarse and many very fine and fine roots; few medium and coarse and Taxonomic Class: Fine, smectitic, frigid Entic many very fine and fine pores; few worm casts; Haplustolls common medium masses of lime; strongly effervescent; moderately alkaline (pH 7.9); diffuse Typical Pedon wavy boundary. Linwell silty clay loam, in a cultivated field, 60 feet C—39 to 67 inches; light brownish gray (2.5Y 6/2) south and 590 feet west of the northeast corner of silty clay loam, dark grayish brown (2.5Y 4/2) sec. 15, T. 18 N., R. 15 E.; Fergus County, Montana. moist; few distinct yellowish brown (10YR 5/6) redox concentrations; massive; very hard, friable, Ap—0 to 6 inches; dark grayish brown (2.5Y 4/2) silty moderately sticky, moderately plastic; few very clay loam, very dark grayish brown (10YR 3/2) fine and fine roots; few medium and many very moist; the surface 1 inch has moderate fine fine and fine pores; few fine masses and seams granular structure, and the lower 5 inches has of lime; strongly effervescent; moderately alkaline moderate very fine and fine subangular blocky (pH 7.9). structure; hard, friable, moderately sticky, moderately plastic; few medium and many very Range in Characteristics fine and fine roots; many very fine and fine pores; slightly effervescent; slightly alkaline (pH 7.7); Soil temperature: 42 to 47 degrees F clear wavy boundary. Moisture control section: Between 4 and 12 inches Bw—6 to 11 inches; grayish brown (2.5Y 5/2) silty Thickness of the mollic epipedon: 7 to 15 inches clay loam, dark grayish brown (10YR 4/2) moist; Depth to the Bk horizon: 12 to 24 inches moderate medium prismatic structure parting to Note: Some pedons do not have a C horizon. 90 Soil Survey

A horizon A—0 to 2 inches; grayish brown (2.5Y 5/2) silt loam, Hue: 10YR or 2.5Y dark grayish brown (2.5Y 4/2) moist; moderate Value: 4 or 5 dry; 2 or 3 moist fine subangular blocky structure; soft, friable, Chroma: 1 or 2 nonsticky, nonplastic; many very fine and fine Texture (less than 2 mm): Clay loam, silty clay roots; neutral (pH 7.2); clear smooth boundary. loam, or loam Bw—2 to 11 inches; grayish brown (2.5Y 5/2) silt Clay content: 30 to 40 percent loam, dark grayish brown (2.5Y 4/2) moist; strong Content of rock fragments: 0 to 15 percent—0 to medium angular blocky structure; slightly hard, 5 percent stones and cobbles; 0 to 15 percent friable, nonsticky, nonplastic; many very fine and gravel fine roots and pores; neutral (pH 7.4); clear Reaction: pH 6.6 to 7.8 smooth boundary. Bk—11 to 28 inches; light brownish gray (2.5Y 6/2) Bw horizon silt loam, grayish brown (2.5Y 4/2) moist; Hue: 10YR or 2.5Y massive; slightly hard, friable, nonsticky, Value: 5 or 6 dry; 4 or 5 moist nonplastic; common very fine roots; many fine Chroma: 2 or 3 pores; common distinct masses of lime; strongly Texture (less than 2 mm): Clay loam, silty clay effervescent; moderately alkaline (pH 8.4); loam, or silty clay gradual smooth boundary. Clay content: 35 to 45 percent By—28 to 60 inches; light brownish gray (2.5Y 6/2) Content of rock fragments: 0 to 15 percent gravel silt loam, dark grayish brown (2.5Y 4/2) moist; Calcium carbonate equivalent: 1 to 10 percent massive; slightly hard, friable, moderately sticky Reaction: pH 7.4 to 8.4 and nonplastic; thin lenses of very fine sandy Bk and C horizons loam; few very fine roots; common threads and Hue: 10YR or 2.5Y nodules of gypsum; strongly effervescent; Value: 5 or 6 dry; 4 or 5 moist moderately alkaline (pH 8.4). Chroma: 2 or 3 Range in Characteristics Texture (less than 2 mm): Clay loam, silty clay loam, silty clay, or clay Soil temperature: 42 to 47 degrees F Clay content: 35 to 45 percent Moisture control section: Between 4 and 12 inches Content of rock fragments: 0 to 15 percent gravel Depth to the Bk horizon: 10 to 12 inches Calcium carbonate equivalent: 5 to 15 percent A horizon Reaction: pH 7.9 to 8.4 Hue: 10YR or 2.5Y Value: 5 or 6 dry; 3 to 5 moist Lonna Series Chroma: 2 to 4 Texture (less than 2 mm): Silt loam Depth class: Very deep (greater than 60 inches) Clay content: 18 to 27 percent Drainage class: Well drained Calcium carbonate equivalent: 5 to 10 percent Permeability: Moderate (0.6 to 2.0 inches/hour) Reaction: pH 7.4 to 8.4 Landform: Fan and stream terrace Bw horizon Parent material: Silty alluvium Hue: 10YR or 2.5Y Slope range: 2 to 8 percent Value: 5 or 6 dry; 4 or 5 moist Elevation range: 3,750 to 5,200 feet Chroma: 2 to 4 Mean annual precipitation: 10 to 14 inches Texture (less than 2 mm): Silt loam or silty clay Mean annual air temperature: 43 to 46 degrees F loam Frost-free period: 95 to 125 days Clay content: 18 to 35 percent Calcium carbonate equivalent: 0 to 10 percent Taxonomic Class: Fine-silty, mixed, superactive, Reaction: pH 7.4 to 8.4 frigid Aridic Haplustepts Bk horizon Typical Pedon Hue: 10YR or 2.5Y Lonna silt loam, in an area of Lonna silt loam, 2 to Value: 5 to 7 dry; 4 to 6 moist 8 percent slopes, 1,800 feet south and 100 feet west Chroma: 2 to 4 of the northeast corner of sec. 6, T. 3 N., R. 20 E.; Texture (less than 2 mm): Silt loam or silty clay Stillwater County, Montana. loam Sweet Grass County Area, Montana—Part I 91

Clay content: 18 to 35 percent fine roots; many very fine and fine pores; slightly Calcium carbonate equivalent: 5 to 12 percent acid (pH 6.2); clear smooth boundary. Electrical conductivity: 2 to 8 mmhos/cm Bt1—8 to 15 inches; brown (10YR 5/3) clay loam, Sodium adsorption ratio: 1 to 13 brown (10YR 4/3) moist; moderate medium Reaction: pH 7.9 to 9.0 subangular blocky structure; slightly hard, friable, moderately sticky, moderately plastic; many very By horizon fine and fine roots; many very fine and fine pores; Hue: 10YR or 2.5Y common distinct discontinuous dark yellowish Value: 5 to 7 dry; 4 to 6 moist brown (10YR 4/4) moist; clay films on faces of Chroma: 2 to 4 peds and lining pores; neutral (pH 6.8); clear Texture (less than 2 mm): Stratified silt loam and smooth boundary. very fine sandy loam Bt2—15 to 21 inches; pale brown (10YR 6/3) clay Clay content: 18 to 27 percent loam; brown (10YR 5/3) moist; moderate medium Calcium carbonate equivalent: 5 to 15 percent and coarse subangular blocky structure; slightly Electrical conductivity: 2 to 8 mmhos/cm hard, friable, moderately sticky, moderately Sodium adsorption ratio: 1 to 13 plastic; many fine roots; many fine pores; Reaction: pH 7.9 to 9.0 common faint discontinuous yellowish brown (10YR 5/4) moist; clay films on faces of peds and Lymanson Series lining pores; neutral (pH 7.0); abrupt smooth boundary. Depth class: Moderately deep (20 to 40 inches) Bk—21 to 31 inches; light gray (2.5Y 7/2) gravelly Drainage class: Well drained loam, light brownish gray (2.5Y 6/2) moist; weak Permeability: Moderate (0.6 to 2.0 inches/hour) coarse prismatic structure; soft, very friable, Landform: Mountain slightly sticky, slightly plastic; common fine roots; Parent material: Loamy residuum weathered from many very fine and fine pores; fine and medium sandstone and siltstone soft masses of lime; 17 percent gravel; strongly Slope range: 2 to 50 percent effervescent; moderately alkaline (pH 8.0); clear Elevation range: 5,500 to 7,500 feet smooth boundary. Mean annual precipitation: 20 to 25 inches Cr—31 to 60 inches; thinly bedded calcareous Mean annual air temperature: 36 to 38 degrees F sandstone and siltstone. Frost-free period: 50 to 70 days Range in Characteristics Taxonomic Class: Fine-loamy, mixed, superactive Soil temperature: 39 to 44 degrees F Ustic Argicryolls Moisture control section: Between 4 and 12 inches Typical Pedon Thickness of the mollic epipedon: 7 to 15 inches Depth to the Bk horizon: 10 to 23 inches Lymanson loam, in an area of Cheadle-Lymanson- Depth to the Cr horizon: 20 to 40 inches Gilispie complex, 2 to 15 percent slopes, in an area Note: Some pedons have a Btk horizon. of rangeland, 2,200 feet south and 1,100 feet west of the northeast corner of sec. 36, T. 2 S., R. 12 E.; A horizons USGS McLeod Basin topographic quadrangle (lat. Hue: 7.5YR, 10YR, or 2.5Y 45o37'12" N.; long. 110o10'51" W.) Value: 3 to 5 dry; 2 or 3 moist Chroma: 1 to 3 A1—0 to 4 inches; very dark grayish brown (10YR Texture (less than 2 mm): Loam 3/2) loam, black (10YR 2/1) moist; weak very fine Clay content: 20 to 27 percent and fine granular structure; soft, very friable, Content of rock fragments: 0 to 35 percent—0 to nonsticky, slightly plastic; many very fine and fine 20 percent stones and cobbles; 0 to 15 percent roots; many very fine and fine pores; slightly acid gravel (pH 6.2); clear smooth boundary. Reaction: pH 6.6 to 8.4 A2—4 to 8 inches; very dark grayish brown (10YR 3/2), loam, very dark brown (10YR 2/2) moist; Bt horizons weak medium subangular blocky structure Hue: 7.5YR, 10YR, or 2.5Y parting to weak fine granular; soft, very friable, Value: 4 to 6 dry; 3 to 5 moist slightly sticky, slightly plastic; many very fine and Chroma: 2 to 4 92 Soil Survey

Texture (less than 2 mm): Loam, clay loam, or friable, slightly sticky, slightly plastic; common sandy clay loam very fine and fine roots; common very fine and Clay content: 20 to 35 percent fine pores; slightly effervescent; slightly alkaline Content of rock fragments: 0 to 35 percent gravel (pH 7.8); clear smooth boundary. or channers Bk1—12 to 33 inches; light brownish gray (2.5Y 6/2) Reaction: pH 7.4 to 8.4 loam, grayish brown (2.5Y 5/2) moist; weak coarse prismatic structure parting to weak Bk horizon medium subangular blocky; slightly hard, very Hue: 7.5YR, 10YR, or 2.5Y friable, slightly sticky, slightly plastic; common Value: 5 to 7 dry; 4 to 6 moist very fine and fine roots; common very fine and Chroma: 2 to 4 fine pores; few fine threads of lime; strongly Texture (less than 2 mm): Loam, sandy loam, fine effervescent; moderately alkaline (pH 8.2); sandy loam, or sandy clay loam gradual smooth boundary. Clay content: 15 to 27 percent Bk2—33 to 48 inches; light gray (2.5Y 7/2) loam, light Content of rock fragments: 0 to 35 percent gravel brownish gray (2.5Y 6/2) moist; weak coarse or channers prismatic structure; slightly hard, very friable, Calcium carbonate equivalent: 5 to 15 percent slightly sticky, slightly plastic; few fine roots; few Reaction: pH 7.9 to 9.0 fine pores; common fine threads and medium soft masses of lime; strongly effervescent; moderately Macar Series alkaline (pH 8.4); gradual smooth boundary. Bk3—48 to 60 inches; light gray (2.5Y 7/2) loam, light Depth class: Very deep (greater than 60 inches) brownish gray (2.5Y 6/2) moist; weak coarse Drainage class: Well drained prismatic structure; slightly hard, very friable, Permeability: Moderate (0.6 to 2.0 inches/hour) slightly sticky, slightly plastic; few fine roots; few Landform: Fan, hill, stream terrace, fan on fine pores; common fine threads and medium soft escarpment, swale on escarpment, fan on plain, masses of lime; 10 percent gravel; violently and swale on plain effervescent; strongly alkaline (pH 8.6). Parent material: Loamy alluvium Slope range: 0 to 25 percent Range in Characteristics Elevation range: 3,900 to 6,200 feet Soil temperature: 42 to 47 degrees F Mean annual precipitation: 15 to 20 inches Moisture control section: Between 4 and 12 inches Mean annual air temperature: 39 to 45 degrees F Depth to the Bk horizon: 11 to 24 inches Frost-free period: 70 to 115 days Note: Some pedons have a BC horizon. Taxonomic Class: Fine-loamy, mixed, superactive, A horizon frigid Typic Haplustepts Hue: 10YR, 2.5Y, or 5Y Value: 4 to 6 dry; 3 to 5 moist Typical Pedon Chroma: 2 to 4 Macar loam, in an area of Macar loam, calcareous Texture (less than 2 mm): Loam surface, 4 to 8 percent slopes, in an area of Clay content: 18 to 27 percent rangeland, 1,000 feet south and 2,000 feet east of Content of rock fragments: 0 to 30 percent—0 to the northwest corner of sec. 36, T. 5 N., R. 14 E.; 5 percent cobbles; 0 to 25 percent gravel USGS Melville NW topographic quadrangle (lat. Calcium carbonate equivalent: 0 to 10 percent 46o08'41" N.; long. 109o55'02" W.) Reaction: pH 6.6 to 8.4 A—0 to 4 inches; grayish brown (10YR 5/2) loam, Bw horizon dark grayish brown (10YR 4/2) moist; weak fine Hue: 10YR, 2.5Y, or 5Y granular structure; soft, very friable, slightly sticky, Value: 5 to 7 dry; 4 or 5 moist slightly plastic; many very fine and fine roots; Chroma: 2 to 4 or 6 many very fine and fine pores; slightly Texture (less than 2 mm): Loam, clay loam, or effervescent; slightly alkaline (pH 7.4); clear silty clay loam smooth boundary. Clay content: 18 to 35 percent Bw—4 to 12 inches; grayish brown (2.5Y 5/2) loam, Content of rock fragments: 0 to 5 percent gravel dark grayish brown (2.5Y 4/2) moist; weak Calcium carbonate equivalent: 0 to 10 percent medium subangular blocky structure; soft, very Reaction: pH 6.6 to 8.4 Sweet Grass County Area, Montana—Part I 93

Bk1 horizon southwest corner of sec. 16, T. 1 N., R. 14 E.; USGS Hue: 10YR, 2.5Y, or 5Y Big Timber topographic quadrangle (lat. 45o49'59" N.; Value: 5 to 7 dry; 4 to 6 moist long. 109o59'38" W.) Chroma: 2 to 4 or 6 Texture (less than 2 mm): Loam, clay loam, or Az—0 to 5 inches; dark grayish brown (10YR 4/2) silty clay loam gravelly loam, very dark grayish brown (10YR Clay content: 18 to 35 percent 3/2) moist; weak medium platy structure; slightly Content of rock fragments: 0 to 5 percent gravel hard, friable, slightly sticky, slightly plastic; many Calcium carbonate equivalent: 8 to 15 percent very fine and fine roots; many very fine and fine Reaction: pH 7.4 to 8.4 pores; few fine masses of salt; 20 percent gravel; slightly effervescent; slightly alkaline (pH 7.6); Bk2 and Bk3 horizons abrupt smooth boundary. Hue: 10YR, 2.5Y, or 5Y Bz1—5 to 9 inches; grayish brown (10YR 5/2) loam, Value: 5 to 7 dry; 4 to 6 moist dark grayish brown (10YR 4/2) moist; moderate Chroma: 2 to 4 or 6 medium angular blocky structure; moderately Texture (less than 2 mm): Loam, clay loam, or hard, friable, moderately sticky, slightly plastic; silty clay loam many very fine and fine roots; many very fine and Clay content: 15 to 30 percent fine pores; common fine threads of salt; 5 percent Content of rock fragments: 0 to 5 percent gravel gravel; strongly effervescent; moderately alkaline Calcium carbonate equivalent: 5 to 12 percent (pH 8.4); clear wavy boundary. Reaction: pH 7.4 to 9.0 Bz2—9 to 22 inches; light brownish gray (10YR 6/2) loam, grayish brown (10YR 5/2) moist; weak Marcott Taxadjunct coarse prismatic structure; slightly hard, very friable, slightly sticky, slightly plastic; common Depth class: Very deep (greater than 60 inches) very fine roots; many very fine and fine pores; Drainage class: Somewhat poorly drained common fine and medium masses of salt; 5 Permeability: In the upper 0 to 32 inches = slow percent gravel; strongly effervescent; strongly (0.06 to 0.20 inch/hour); below this depth = alkaline (pH 8.8); clear wavy boundary. moderately rapid (2 to 6 inches/hour) Bkgz—22 to 32 inches; light brownish gray (10YR Landform: Fan, flood plain, and stream terrace 6/2) loam, grayish brown (10YR 5/2) moist; Parent material: Clayey alluvium common fine and medium faint yellowish brown Slope range: 0 to 4 percent (10YR 5/4) moist, redox concentrations; weak Elevation range: 3,750 to 6,000 feet coarse prismatic structure; slightly hard, very Mean annual precipitation: 10 to 19 inches friable, slightly sticky, slightly plastic; few very fine Mean annual air temperature: 43 to 46 degrees F roots; many very fine and fine pores; common Frost-free period: 85 to 130 days fine and medium threads of lime; common fine masses of salt; 5 percent gravel; strongly Taxonomic Class: Fine-loamy, mixed, superactive, effervescent; strongly alkaline (pH 9.0); clear frigid Oxyaquic Haplustolls smooth boundary. 2Cg1—32 to 41 inches; grayish brown (10YR 5/2) The Marcott soils as mapped in this survey area are gravelly fine sandy loam, dark grayish brown taxadjunct to the series. They are outside the series (10YR 4/2) moist; common medium and coarse range in that they have a mixed mineralogy class and distinct strong brown (7.5YR 4/6) moist, redox the linear extensibility is not 6.0 or more between the concentrations; single grain; soft, loose, mineral soil surface and a depth of 40 inches. Use nonsticky, nonplastic; 25 percent gravel; slightly and management are not significantly affected. effervescent; strongly alkaline (pH 8.6); abrupt Marcott series classifies as Fine, smectitic, frigid smooth boundary. Aquertic Haplustolls. 3Cg2—41 to 60 inches; light brownish gray (2.5Y 6/2) very gravelly loamy coarse sand, dark grayish Typical Pedon brown (2.5Y 4/2) moist; single grain; loose, Marcott gravelly loam, in an area of Marcott-Larry nonsticky, nonplastic; thin strata of finer textured complex, 0 to 4 percent slopes, in an area of material; slightly effervescent; strongly alkaline rangeland, 1,500 feet north and 1,700 feet east of the (pH 8.6). 94 Soil Survey

Range in Characteristics Calcium carbonate equivalent: 5 to 15 percent Electrical conductivity: 4 to 8 mmhos/cm Soil temperature: 41 to 47 degrees F Sodium adsorption ratio: 0 to 30 Moisture control section: Between 4 and 12 inches Reaction: pH 7.4 to 9.0 Thickness of the mollic epipedon: 7 to 15 inches; the upper 7 inches, when mixed, meet the 3Cg horizon requirements of a mollic epipedon. Hue: 10YR, 2.5Y, or 5Y Depth to the seasonal high water table: 24 to Value: 4 to 7 dry; 4 to 6 moist 60 inches Chroma: 1 to 3 Depth to the Bk horizon: 12 to 24 inches Texture (less than 2 mm): Loamy sand, loamy Depth to the 3C horizon: 36 to 50 inches coarse sand, or sand Clay content: 10 to 15 percent Az horizon Content of rock fragments: 35 to 60 percent—0 to Hue: 10YR, 2.5Y, or 5Y 10 percent cobbles; 0 to 60 percent gravel Value: 3 to 5 dry; 2 or 3 moist Calcium carbonate equivalent: 5 to 15 percent Chroma: 1 or 2 Electrical conductivity: 2 to 8 mmhos/cm Texture (less than 2 mm): Clay loam or loam Sodium adsorption ratio: 0 to 20 Clay content: 15 to 35 percent Reaction: pH 7.4 to 9.0 Content of rock fragments: 0 to 35 percent—0 to 5 percent cobbles; 0 to 30 percent gravel Electrical conductivity: 4 to 8 mmhos/cm Marmarth Series Sodium adsorption ratio: 0 to 20 Reaction: pH 6.6 to 8.4 Depth class: Moderately deep (20 to 40 inches) Drainage class: Well drained Bz horizons Permeability: Moderate (0.6 to 2.0 inches/hour) Hue: 10YR, 2.5Y, or 5Y Landform: Hill, terrace, and swale on plain Value: 4 to 7 dry; 4 to 6 moist Parent material: Loamy residuum weathered from Chroma: 1 to 3 sandstone and siltstone Texture (less than 2 mm): Loam or clay loam Slope range: 2 to 15 percent Clay content: 18 to 35 percent Elevation range: 3,750 to 5,200 feet Content of rock fragments: 0 to 15 percent gravel Mean annual precipitation: 10 to 14 inches Electrical conductivity: 2 to 8 mmhos/cm Mean annual air temperature: 43 to 46 degrees F Sodium adsorption ratio: 0 to 25 Frost-free period: 95 to 125 days Calcium carbonate equivalent: 3 to 12 percent Reaction: pH 7.4 to 8.4 Taxonomic Class: Fine-loamy, mixed, superactive, Bkgz horizon frigid Aridic Argiustolls Hue: 10YR, 2.5Y, or 5Y Typical Pedon Value: 4 to 7 dry; 4 to 6 moist Chroma: 1 to 3 Marmarth loam, in an area of Marmarth loam, 2 to Texture (less than 2 mm): Loam or clay loam 8 percent slopes, in an area of rangeland, 1,200 feet Clay content: 18 to 35 percent south and 400 feet east of the northwest corner of Content of rock fragments: 0 to 15 percent gravel sec. 11, T. 3 N., R. 17 E.; USGS Gibson topographic Calcium carbonate equivalent: 3 to 12 percent quadrangle (lat. 46o01'42" N.; long. 109o35'16" W.) Electrical conductivity: 2 to 8 mmhos/cm A—0 to 5 inches; grayish brown (10YR 5/2) loam, Sodium adsorption ratio: 0 to 25 very dark grayish brown (10YR 3/2) moist; weak Reaction: pH 7.4 to 8.4 fine granular structure; soft, very friable, slightly 2Cg horizon sticky, slightly plastic; many very fine and fine Hue: 10YR, 2.5Y, or 5Y roots; many very fine and fine pores; neutral Value: 4 to 7 dry; 4 to 6 moist (pH 6.7); clear smooth boundary. Chroma: 1 to 3 Bt1—5 to 9 inches; brown (10YR 4/3) loam, dark Texture (less than 2 mm): Sandy loam, fine sandy brown (10YR 3/3) moist; weak fine and medium loam, or loam subangular blocky structure; slightly hard, very Clay content: 10 to 27 percent friable, slightly sticky, slightly plastic; many very Content of rock fragments: 10 to 35 percent fine and fine roots; many very fine pores; gravel common faint discontinuous dark yellowish brown Sweet Grass County Area, Montana—Part I 95

(10YR 3/4) moist; clay films on faces of peds and Content of rock fragments: 0 to 5 percent gravel lining pores; slightly alkaline (pH 7.6); clear Reaction: pH 6.1 to 7.8 smooth boundary. Bk horizons Bt2—9 to 15 inches; brown (10YR 5/3) clay loam, Hue: 10YR, 2.5Y, or 5Y dark brown (10YR 4/3) moist; moderate coarse Value: 5 to 7 dry; 4 to 6 moist subangular blocky structure parting to moderate Chroma: 2 to 4 fine and medium subangular blocky; slightly hard, Texture (less than 2 mm): Loam, very fine sandy very friable, moderately sticky, moderately plastic; loam, or clay loam common very fine and fine roots; common very Clay content: 15 to 30 percent fine pores; common distinct discontinuous brown Content of rock fragments: 0 to 15 percent gravel (7.5YR 4/2) moist; clay films on faces of peds and or channers lining pores; slightly alkaline (pH 7.8); abrupt Calcium carbonate equivalent: 5 to 15 percent smooth boundary. Reaction: pH 7.4 to 8.4 Bk1—15 to 25 inches; light gray (10YR 7/2) loam, light brownish gray (10YR 6/2) moist; weak coarse prismatic structure; soft, very friable, slightly sticky, slightly plastic; few fine roots; Martinsdale Series common very fine and fine pores; few fine Depth class: Very deep (greater than 60 inches) threads and fine and medium soft masses of Drainage class: Well drained lime; 5 percent gravel; strongly effervescent; Permeability: Moderately slow (0.2 to 0.6 inch/hour) moderately alkaline (pH 8.2); clear smooth Landform: Fan and terrace boundary. Parent material: Loamy alluvium Bk2—25 to 34 inches; light gray (2.5Y 7/2) very fine Slope range: 0 to 15 percent sandy loam, light brownish gray (2.5Y 6/2) moist; Elevation range: 4,200 to 6,000 feet weak coarse prismatic structure; soft, very friable, Mean annual precipitation: 15 to 19 inches nonsticky, nonplastic; few fine roots; common Mean annual air temperature: 43 to 45 degrees F very fine and fine pores; few fine threads and soft Frost-free period: 85 to 115 days masses of lime; 10 percent gravel; strongly effervescent; moderately alkaline (pH 8.2); clear Taxonomic Class: Fine-loamy, mixed, superactive, smooth boundary. frigid Typic Argiustolls Cr—34 to 60 inches; soft calcareous sandstone. Typical Pedon Range in Characteristics Martinsdale gravelly loam, in an area of Martinsdale Soil temperature: 42 to 46 degrees F gravelly loam, 0 to 4 percent slopes, in an area of Moisture control section: Between 4 and 12 inches rangeland, 800 feet south and 500 feet west of Thickness of the mollic epipedon: 7 to 15 inches the northeast corner of sec. 32, T. 5 N., R. 14 E.; Depth to the Bk horizon: 11 to 20 inches USGS Melville NW topographic quadrangle (lat. Depth to the Cr horizon: 20 to 40 inches 46o08'44" N.; long. 109o59'24" W.) A horizon A—0 to 4 inches; brown (10YR 4/3) gravelly loam, Hue: 10YR very dark brown (10YR 2/2) moist; weak fine Value: 5 dry; 2 or 3 moist granular structure; slightly hard, very friable, Chroma: 2 or 3 slightly sticky, slightly plastic; many very fine Texture (less than 2 mm): Loam and fine roots; many very fine and fine pores; Clay content: 20 to 27 percent 15 percent gravel; neutral (pH 7.0); clear smooth Content of rock fragments: 0 to 5 percent gravel boundary. Reaction: pH 6.1 to 7.3 Bt1—4 to 10 inches; brown (7.5YR 4/4) clay loam, Bt horizons dark brown (7.5YR 3/3) moist; moderate fine and Hue: 10YR or 2.5Y medium prismatic structure parting to moderate Value: 4 to 6 dry; 3 or 4 moist very fine and fine subangular blocky; very hard, Chroma: 2 to 4 friable, moderately sticky, moderately plastic; Texture (less than 2 mm): Loam, clay loam, or many very fine and fine roots; many very fine and sandy clay loam fine pores; many prominent continuous dark Clay content: 18 to 35 percent brown (7.5YR 3/4) moist; clay films on faces of 96 Soil Survey

peds and lining pores; 10 percent gravel; neutral Clay content: 25 to 35 percent (pH 7.0); clear smooth boundary. Content of rock fragments: 0 to 15 percent gravel Bt2—10 to 16 inches; yellowish brown (10YR 5/4) Reaction: pH 6.6 to 8.4 loam, brown (10YR 4/3) moist; strong medium Bt2 horizon and coarse subangular blocky structure parting to Hue: 7.5YR, 10YR, or 2.5Y strong fine and medium subangular blocky; very Value: 4 to 6 dry; 3 or 4 moist hard, friable, slightly sticky, slightly plastic; many Chroma: 3 or 4 very fine and fine roots; many very fine pores; Texture (less than 2 mm): Loam, clay loam, or common distinct discontinuous (7.5YR 3/4) moist; sandy clay loam clay films on faces of peds; 10 percent gravel; Clay content: 25 to 35 percent slightly alkaline (pH 7.4); abrupt smooth Content of rock fragments: 0 to 15 percent gravel boundary. Reaction: pH 6.6 to 8.4 Bk1—16 to 29 inches; light gray (10YR 7/2) gravelly sandy loam, brown (10YR 5/3) moist; moderate Bk horizons medium and coarse subangular blocky structure; Hue: 10YR or 2.5Y moderately hard, very friable, slightly sticky, Value: 6 to 8 dry; 4 to 7 moist slightly plastic; common very fine and fine roots; Chroma: 2 to 4 common very fine and fine pores; carbonate Texture (less than 2 mm): Sandy loam, loam, clay coats on rock fragments; few soft masses of lime; loam, or sandy clay loam 20 percent gravel; violently effervescent; Clay content: 15 to 35 percent moderately alkaline (pH 8.4); clear wavy Content of rock fragments: 0 to 35 percent—0 to boundary. 15 percent cobbles; 0 to 20 percent gravel Bk2—29 to 60 inches; light brownish gray (10YR 6/2) Calcium carbonate equivalent: 15 to 35 percent gravelly sandy loam, grayish brown (10YR 5/2) Electrical conductivity: 0 to 4 mmhos/cm moist; weak fine and medium subangular blocky Gypsum content: 0 to 1 percent structure; slightly hard, very friable, slightly sticky, Reaction: pH 7.4 to 9.0 slightly plastic; few very fine and fine roots; common very fine and fine pores; carbonate coats on rock fragments; few soft masses of lime McIlwaine Series and thin threads of lime; 20 percent gravel; Depth class: Very deep (greater than 60 inches) violently effervescent; strongly alkaline (pH 8.6). Drainage class: Somewhat poorly drained Permeability: In the upper 0 to 24 inches = Range in Characteristics moderately rapid (2 to 6 inches/hour); below this Soil temperature: 38 to 47 degrees F depth = rapid (6 to 20 inches/hour) Moisture control section: Between 4 and 12 inches Landform: Flood plain Thickness of the mollic epipedon: 7 to 16 inches Parent material: Coarse loamy over sandy and Depth to the calcic horizon: 11 to 30 inches gravelly alluvium Note: Some pedons have a Btk horizon and, below a Slope range: 0 to 2 percent depth of 40 inches, a BC horizon. Elevation range: 3,750 to 6,000 feet Mean annual precipitation: 10 to 19 inches A horizon Mean annual air temperature: 43 to 46 degrees F Hue: 7.5YR or 10YR Frost-free period: 85 to 130 days Value: 4 or 5 dry; 2 or 3 moist Chroma: 2 or 3 Taxonomic Class: Coarse-loamy over sandy or Texture (less than 2 mm): Loam sandy-skeletal, mixed, superactive, frigid Cumulic Clay content: 15 to 35 percent Haplustolls Content of rock fragments: 0 to 25 percent—0 to 10 percent cobbles; 0 to 15 percent gravel Typical Pedon Reaction: pH 6.6 to 7.8 McIlwaine loam, in an area of Nesda-McIlwaine Bt1 horizon loams, 0 to 2 percent slopes, in an area of deciduous Hue: 7.5YR, 10YR, or 2.5Y forest, 2,300 feet north and 1,300 feet west of the Value: 4 or 5 dry; 2 or 3 moist southeast corner of sec. 34, T. 1 N., R. 14 E.; USGS Chroma: 2 to 4 Big Timber topographic quadrangle (lat. 45o47'30" N.; Texture (less than 2 mm): Clay loam long. 109o57'53" W.) Sweet Grass County Area, Montana—Part I 97

A—0 to 9 inches; dark grayish brown (10YR 4/2) Clay content: 5 to 18 percent loam, very dark brown (10YR 2/2) moist; weak Content of rock fragments: 0 to 15 percent—0 to very fine and fine granular structure; soft, very 5 percent cobbles; 0 to 10 percent gravel friable, slightly sticky, slightly plastic; common Calcium carbonate equivalent: 5 to 10 percent very fine and fine roots; common very fine pores; Reaction: pH 6.6 to 7.8 5 percent gravel; slightly effervescent; slightly 2C horizon alkaline (pH 7.6); clear smooth boundary. Hue: 7.5YR, 10YR, or 2.5Y A2—9 to 21 inches; dark grayish brown (10YR 4/2) Value: 6 to 8 dry; 4 to 6 moist fine sandy loam, very dark brown (10YR 2/2) Chroma: 1 to 3 moist; massive; slightly hard, very friable, Texture (less than 2 mm): Coarse sand or loamy nonsticky, nonplastic; common very fine roots; sand common very fine pores; thin strata of light Clay content: 1 to 5 percent brownish gray (10YR 6/2) loam and loamy fine Content of rock fragments: 35 to 80 percent—0 to sand, grayish brown (10YR 5/2) moist; 5 percent 10 percent stones; 5 to 20 percent cobbles; gravel; slightly effervescent; slightly alkaline 30 to 50 percent gravel (pH 7.8); clear smooth boundary. Calcium carbonate equivalent: 5 to 10 percent A3—21 to 25 inches; dark grayish brown and grayish Reaction: pH 6.6 to 7.8 brown (10YR 4/2 and 5/2) fine sandy loam, very dark brown and grayish brown (10YR 2/2 and 4/2) moist; massive; soft, very friable, nonsticky, nonplastic; few very fine roots; common very fine Meadowcreek Series pores; thin strata of grayish brown (10YR 5/2) Depth class: Very deep (greater than 60 inches) moist, loam and loamy fine sand; 10 percent Drainage class: Somewhat poorly drained gravel; slightly effervescent; slightly alkaline Permeability: In the upper 0 to 31 inches = moderate (pH 7.8); abrupt wavy boundary. (0.6 to 2.0 inches/hour); below this depth = rapid 2C—25 to 60 inches; light brownish gray (10YR 7/2) (6 to 20 inches/hour) extremely gravelly coarse sand, grayish brown Landform: Flood plain, stream terrace, drainageway (10YR 5/2) moist; single grain; loose, nonsticky, on fan nonplastic; 45 percent gravel; 20 percent cobbles; Parent material: Fine-loamy over sandy and gravelly 5 percent stones; disseminated lime with alluvium segregated lime around rock fragments; slightly Slope range: 0 to 2 percent to strongly effervescent; slightly alkaline (pH 7.4). Elevation range: 3,750 to 6,200 feet Range in Characteristics Mean annual precipitation: 10 to 20 inches Mean annual air temperature: 39 to 46 degrees F Soil temperature: 40 to 43 degrees F Frost-free period: 70 to 130 days Moisture control section: Between 8 and 24 inches Depth to the seasonal high water table: 24 to Taxonomic Class: Fine-loamy over sandy or sandy- 42 inches skeletal, mixed, superactive, frigid Fluvaquentic Depth to the 2C horizon: 20 to 40 inches Haplustolls A horizon Hue: 7.5YR, 10YR, or 2.5Y Typical Pedon Value: 4 or 5 dry; 2 or 3 moist Chroma: 2 or 3 Meadowcreek loam, in an area of Meadowcreek- Texture (less than 2 mm): Loam Nesda loams, 0 to 2 percent slopes, in an area of Clay content: 7 to 15 percent hayland, 2,900 feet north and 1,400 feet west of the Content of rock fragments: 0 to 15 percent—0 to southeast corner of sec. 8, T. 1 S., R. 13 E.; USGS 5 percent cobbles; 0 to 10 percent gravel Kelly Hills topographic quadrangle (lat. 45o45'49" N.; Reaction: pH 6.6 to 7.8 long. 110o08'31" W.) A2 and A3 horizons Ap—0 to 5 inches; grayish brown (10YR 5/2) loam, Hue: 7.5YR, 10YR, or 2.5Y very dark grayish brown (10YR 3/2) moist; Value: 4 or 5 dry; 2 to 4 moist moderate very fine and fine granular structure; Chroma: 2 or 3 soft, very friable, slightly sticky, slightly plastic; Texture (less than 2 mm): Fine sandy loam or common very fine and fine roots; few very fine loam with strata of finer and coarser material pores; 5 percent gravel; 2 percent cobbles; 98 Soil Survey

slightly alkaline (pH 7.4); abrupt smooth A horizons boundary. Hue: 10YR or 2.5Y A2—5 to 10 inches; grayish brown (10YR 5/2) loam, Value: 4 or 5 dry; 2 or 3 moist very dark grayish brown (10YR 3/2) moist; weak Chroma: 1 or 2 very fine and fine subangular blocky structure; Texture (less than 2 mm): Loam or clay loam slightly hard, friable, slightly sticky, slightly plastic; Clay content: 18 to 35 percent common very fine and fine roots; few very fine Content of rock fragments: 0 to 15 percent—0 to pores; slightly alkaline (pH 7.6); clear smooth 5 percent cobbles; 0 to 10 percent gravel boundary. Reaction: pH 7.4 to 8.4 A3—10 to 15 inches; grayish brown (2.5Y 5/2) clay Bg horizons loam, very dark grayish brown (2.5Y 3/2) moist; Hue: 10YR, 2.5Y, or 5Y weak medium prismatic structure parting to weak Value: 5 or 6 dry; 3 or 4 moist fine subangular blocky; slightly hard, friable, Chroma: 1 to 3 slightly sticky, slightly plastic; few very fine roots; Redox concentrations: Few to many; chroma of 6 few very fine pores; slightly effervescent; Redox depletions: None to common; chroma of 0 moderately alkaline (pH 8.2); clear smooth or 1 boundary. Texture (less than 2 mm): Loam, sandy loam, fine Bg1—15 to 26 inches; grayish brown and light sandy loam, or sandy clay loam brownish gray (2.5Y 5/2 and 6/2) stratified loam, Clay content: 18 to 25 percent dark grayish brown (2.5Y 4/2) moist; few fine Content of rock fragments: 0 to 5 percent gravel distinct strong brown (7.5YR 4/6) moist, redox Calcium carbonate equivalent: 0 to 10 percent concentrations; weak coarse prismatic structure; Reaction: pH 6.6 to 7.8 slightly hard, friable, slightly sticky, slightly plastic; few very fine roots; few very fine pores; slightly 2C horizon effervescent; slightly alkaline (pH 7.8); clear Hue: 10YR, 2.5Y, or 5Y smooth boundary. Value: 5 to 7 dry; 3 to 6 moist Bg2—26 to 32 inches; brown (10YR 5/3) fine sandy Chroma: 1 to 3 loam, dark brown (10YR 4/3) moist; common Texture (less than 2 mm): Loamy sand or sand medium prominent strong brown (7.5YR 4/6) Clay content: 0 to 10 percent moist, redox concentrations, common medium Content of rock fragments: 35 to 75 percent—0 to faint dark gray (2.5Y 4/1) moist, redox depletions; 15 percent stones and cobbles; 35 to weak coarse prismatic structure; soft, very friable, 70 percent gravel nonsticky, nonplastic; few very fine roots; Calcium carbonate equivalent: 0 to 10 percent common very fine pores; slightly effervescent; Reaction: pH 6.1 to 7.3 slightly alkaline (pH 7.6); abrupt smooth boundary. 2C—32 to 60 inches; light gray (10YR 7/2) very Meagher Series gravelly coarse sand, grayish brown and light brownish gray (10YR 5/2 and 6/2) moist; single Depth class: Very deep (greater than 60 inches) grain; loose, nonsticky, nonplastic; common Drainage class: Well drained carbonate coats on undersides of rock fragments; Permeability: In the upper 0 to 30 inches = moderate 40 percent gravel; 5 percent cobbles; 3 percent (0.6 to 2.0 inches/hour); below this depth = stones; slightly to strongly effervescent; moderately rapid (2 to 6 inches/hour) moderately alkaline (pH 8.4). Landform: Terrace Parent material: Loamy alluvium Range in Characteristics Slope range: 2 to 8 percent Elevation range: 4,200 to 6,000 feet Soil temperature: 42 to 47 degrees F Mean annual precipitation: 15 to 19 inches Moisture control section: Between 4 and 12 inches Mean annual air temperature: 43 to 45 degrees F Thickness of the mollic epipedon: 10 to 15 inches Frost-free period: 85 to 115 days Depth to the seasonal high water table: 24 to 42 inches Taxonomic Class: Fine-loamy, mixed, superactive, Depth to the 2C horizon: 20 to 40 inches frigid Typic Argiustolls Sweet Grass County Area, Montana—Part I 99

Typical Pedon fine pores; many carbonate coats on rock fragments; many fine and medium masses of Meagher gravelly loam, in an area of Meagher lime; 40 percent gravel; 10 percent cobbles; gravelly loam, 2 to 8 percent slopes, in an area of violently effervescent; moderately alkaline rangeland, 2,800 feet south and 2,200 feet west of (pH 8.4). the northeast corner of sec. 6, T. 2 S., R. 13 E.; USGS McLeod topographic quadrangle (lat. 45o41'22" N.; Range in Characteristics long. 110o02'29" W.) Soil temperature: 40 to 45 degrees F A—0 to 7 inches; dark grayish brown (10YR 4/2) Moisture control section: Between 4 and 12 inches gravelly loam, very dark grayish brown (10YR Thickness of the mollic epipedon: 7 to 12 inches 3/2) moist; moderate medium subangular blocky Depth to the Bk horizon: 11 to 20 inches structure parting to weak fine and medium Depth to the 2Bk horizon: 20 to 35 inches granular; slightly hard, friable, slightly sticky, A horizon slightly plastic; common fine and many very fine Hue: 7.5YR or 10YR roots; common fine and many very fine pores; Value: 3 to 5 dry; 2 or 3 moist 10 percent gravel; 5 percent cobbles; neutral Chroma: 2 or 3 (pH 6.6); abrupt smooth boundary. Texture (less than 2 mm): Loam Bt1—7 to 12 inches; yellowish brown (10YR 5/4) clay Clay content: 18 to 27 percent loam, brown (10YR 4/3) moist; moderate coarse Content of rock fragments: 0 to 35 percent—0 to prismatic structure parting to moderate fine and 15 percent stones and cobbles; 0 to medium subangular blocky; moderately hard, 20 percent gravel firm, moderately sticky, moderately plastic; Reaction: pH 6.6 to 7.8 common very fine and fine roots; common fine and many very fine pores; common faint Bt horizons discontinuous dark yellowish brown (10YR 4/4), Hue: 7.5YR or 10YR moist; clay films on faces of peds and lining Value: 5 or 6 dry; 3 or 4 moist pores; 10 percent gravel; neutral (pH 6.8); clear Chroma: 3 or 4 smooth boundary. Texture (less than 2 mm): Clay loam or loam Bt2—12 to 19 inches; light yellowish brown (10YR Clay content: 20 to 35 percent 6/4) clay loam, dark yellowish brown (10YR 4/4) Content of rock fragments: 0 to 35 percent—0 to moist; moderate coarse prismatic structure 5 percent stones and cobbles; 0 to 30 percent parting to moderate medium and coarse gravel subangular blocky; moderately hard, firm, Reaction: pH 6.6 to 7.8 moderately sticky, moderately plastic; common Bk1 horizon very fine and fine roots; common fine and many Hue: 10YR or 2.5Y very fine pores; common faint discontinuous dark Value: 7 or 8 dry; 6 or 7 moist yellowish brown (10YR 4/4) moist; clay films on Chroma: 2 to 4 faces of peds and lining pores; 10 percent gravel; Texture (less than 2 mm): Loam or sandy loam 2 percent cobbles; neutral (pH 7.2); abrupt Clay content: 18 to 27 percent smooth boundary. Content of rock fragments: 5 to 35 percent—0 to Bk1—19 to 30 inches; very pale brown (10YR 8/3) 5 percent cobbles; 5 to 30 percent gravel gravelly loam, pale brown (10YR 6/3) moist; weak Calcium carbonate equivalent: 15 to 40 percent medium and coarse subangular blocky structure; Gypsum content: 0 to 1 percent soft, friable, slightly sticky, slightly plastic; few Reaction: pH 7.4 to 8.4 very fine roots; common fine and many very fine pores; 20 percent gravel; common fine and 2Bk2 horizon medium masses of lime; violently effervescent; Hue: 10YR or 2.5Y moderately alkaline (pH 8.2); clear smooth Value: 7 or 8 dry; 5 to 7 moist boundary. Chroma: 2 to 4 2Bk2—30 to 60 inches; very pale brown (10YR 8/2) Texture (less than 2 mm): Sandy loam, loam, or very gravelly sandy loam, light brownish gray sandy clay loam (10YR 6/2) moist; weak medium and coarse Clay content: 10 to 25 percent subangular blocky structure; soft, friable, slightly Content of rock fragments: 35 to 70 percent—0 to sticky, slightly plastic; few fine and many very 10 percent cobbles; 35 to 60 percent gravel 100 Soil Survey

Calcium carbonate equivalent: 15 to 40 percent Bky—20 to 31 inches; light brownish gray (2.5Y 6/2) Gypsum content: 0 to 1 percent silty clay, dark grayish brown (2.5Y 4/2) moist; Reaction: pH 7.9 to 8.4 weak coarse prismatic structure; very hard, firm, very sticky, very plastic; few very fine roots; common very fine pores; few very fine platelike Megonot Series crystals of gypsum; few fine masses of lime; 5 percent gravel; strongly effervescent; Depth class: Moderately deep (40 to 60 inches) moderately alkaline (pH 8.4); clear smooth Drainage class: Well drained boundary. Permeability: Slow (0.06 to 0.20 inch/hour) Cr—31 to 60 inches; bedrock; clayey siltstone that Landform: Escarpment, hill, and swale on plain crushes to clay; strongly effervescent. Parent material: Clayey residuum weathered from shale Range in Characteristics Slope range: 2 to 25 percent Elevation range: 3,750 to 5,200 feet Soil temperature: 41 to 47 degrees F Mean annual precipitation: 10 to 14 inches Moisture control section: Between 4 and 12 inches Mean annual air temperature: 43 to 46 degrees F Depth to the Bk horizon: 11 to 17 inches Frost-free period: 95 to 125 days Depth to the Cr horizon: 20 to 40 inches Taxonomic Class: Fine, smectitic, frigid Torrertic A horizon Haplustepts Hue: 10YR or 2.5Y Value: 5 or 6 dry; 4 or 5 moist Typical Pedon Chroma: 2 or 3 Megonot clay loam, in an area of Cabbart-Megonot- Texture (less than 2 mm): Clay loam Kobase clay loams, 2 to 15 percent slopes, in an Clay content: 35 to 40 percent area of rangeland, 2,600 feet south and 1,550 feet Content of rock fragments: 0 to 15 percent gravel west of the northeast corner of sec. 25, T. 4 N., Reaction: pH 6.6 to 7.8 R. 14 E.; USGS Melville topographic quadrangle Bw horizon (lat. 46o04'04" N.; long. 109o55'16" W.) Hue: 10YR or 2.5Y A—0 to 3 inches; light brownish gray (2.5Y 6/2) clay Value: 5 or 6 dry; 4 or 5 moist loam, dark grayish brown (2.5Y 4/2) moist; weak Chroma: 2 or 3 coarse prismatic structure parting to moderate Texture (less than 2 mm): Clay loam, silty clay very fine and fine granular; slightly hard, very loam, silty clay, or clay friable, slightly sticky, moderately plastic; common Clay content: 35 to 45 percent very fine roots; many very fine pores; slightly Content of rock fragments: 0 to 15 percent gravel effervescent; moderately alkaline (pH 8.2); abrupt Calcium carbonate equivalent: 1 to 10 percent smooth boundary. Electrical conductivity: 0 to 4 mmhos/cm Bw—3 to 11 inches; light brownish gray (2.5Y 6/2) Reaction: pH 7.4 to 8.4 clay, dark grayish brown (2.5Y 4/2) moist; Bk horizon moderate coarse prismatic structure parting to Hue: 10YR, 2.5Y, or 5Y strong very fine and fine subangular blocky; Value: 5 or 6 dry; 4 or 5 moist moderately hard, friable, moderately sticky, Chroma: 2 or 3 moderately plastic; common very fine and fine Texture (less than 2 mm): Clay loam, silty clay roots; many very fine pores; strongly effervescent; loam, silty clay, or clay moderately alkaline (pH 8.4); clear smooth Clay content: 35 to 45 percent boundary. Content of rock fragments: 0 to 15 percent gravel Bk—11 to 20 inches; light brownish gray (2.5Y 6/2) Calcium carbonate equivalent: 1 to 15 percent silty clay, grayish brown (2.5Y 5/2) moist; Electrical conductivity: 0 to 4 mmhos/cm moderate fine and medium subangular blocky Reaction: pH 7.4 to 8.4 structure; very hard, friable, very sticky, very plastic; common very fine roots; common very Bky horizon fine pores; common fine and medium soft Hue: 10YR, 2.5Y, or 5Y masses of lime; strongly effervescent; moderately Value: 4 to 6 dry; 4 or 5 moist alkaline (pH 8.4); gradual smooth boundary. Chroma: 2 or 3 Sweet Grass County Area, Montana—Part I 101

Texture (less than 2 mm): Clay loam, silty clay fine and fine subangular blocky; hard, friable, loam, silty clay, or clay moderately sticky, moderately plastic; continuous Clay content: 35 to 45 percent distinct clay films on faces of peds; few unstained Content of rock fragments: 5 to 30 percent gravel sand grains; 10 percent gravel; 5 percent cobbles; Calcium carbonate equivalent: 0 to 5 percent neutral; clear smooth boundary. Electrical conductivity: 0 to 4 mmhos/cm Bt3—8 to 14 inches; dark brown (7.5YR 4/4) clay Gypsum content: 1 to 5 percent loam, dark brown (7.5YR 3/4) moist; strong fine Reaction: pH 6.6 to 8.4 and medium prismatic structure parting to strong very fine and fine subangular blocky; very hard, friable, very sticky, very plastic; discontinuous Melville Series prominent clay films on faces of peds; 5 percent gravel; 5 percent cobbles; neutral; gradual wavy Depth class: Very deep (greater than 60 inches) boundary. Drainage class: Well drained Bt4—14 to 18 inches; brown (10YR 5/3) clay loam, Permeability: In the upper 0 to 23 inches = dark brown (10YR 3/3) moist; strong fine and moderately slow (0.2 to 0.6 inch/hour); below this medium prismatic structure parting to strong very depth = moderate (0.6 to 2.0 inches/hour) fine and fine subangular blocky; very hard, Landform: Outwash plain and terrace friable, moderately sticky, very plastic; continuous Parent material: Gravelly alluvium, gravelly prominent clay films on faces of peds; 5 percent glaciofluvial deposits or gravelly till gravel; 5 percent cobbles; neutral; gradual wavy Slope range: 0 to 15 percent boundary. Elevation range: 5,500 to 7,500 feet Bt5—18 to 23 inches; yellowish brown (10YR 5/4) Mean annual precipitation: 20 to 25 inches gravelly clay loam, dark yellowish brown (10YR Mean annual air temperature: 36 to 38 degrees F 4/4) moist; moderate medium prismatic structure Frost-free period: 50 to 70 days parting to strong fine subangular blocky; hard friable, slightly sticky, slightly plastic; continuous Taxonomic Class: Fine, mixed, superactive Ustic faint clay films on horizontal and distinct on Argicryolls vertical faces of peds; 20 percent gravel; 5 percent cobbles; neutral; abrupt wavy boundary. Typical Pedon Bk1—23 to 30 inches; light gray and white (2.5Y 7/2 and 8/2) very gravelly loam, light olive brown and Melville cobbly loam, in an area of rangeland, pale yellow (2.5Y 5/3 and 7/3) moist; massive; currently Denied Access, 20 feet south and 1,480 feet very hard, friable, slightly sticky, slightly plastic; east of the northwest corner of sec. 3, T. 5 N., many carbonate coats on rock fragments; many R. 13 E.; USGS Porcupine Butte topographic soft masses of lime; 30 percent gravel; 5 percent quadrangle (lat. 46o13'13" N.; long. 110o05'09" W.) cobbles; strongly effervescent; moderately A—0 to 2 inches; dark grayish brown (10YR 4/2) alkaline; clear wavy boundary. cobbly loam, very dark brown (10YR 2/2) moist; 2Bk2—30 to 40 inches; light yellowish brown and weak thin platy structure parting to moderate white (2.5Y 6/3 and 8/3) very gravelly coarse very fine granular; soft, very friable, slightly sandy loam, olive brown and pale yellow (2.5Y sticky, nonplastic; very few clean quartz grains; 4/3 and 7/2) moist; massive; very hard, friable, 10 percent gravel; 15 percent cobbles; neutral; slightly sticky, slightly plastic; many threads of clear smooth boundary. lime throughout and carbonate coats on rock Bt1—2 to 5 inches; dark grayish brown (10YR 4/2) fragments; 40 percent gravel; 10 percent cobbles; gravelly clay loam, very dark brown (10YR 2/2) strongly effervescent; moderately alkaline; moist; weak fine and medium subangular blocky gradual wavy boundary. structure parting to moderate fine granular; soft 2Bk3—40 to 60 inches; light yellowish brown and very friable, slightly sticky, slightly plastic; white (2.5Y 6/3 and 8/3) very cobbly coarse continuous faint clay films on faces of peds; sandy loam, light olive brown and pale yellow few unstained sand grains; 10 percent gravel; (2.5Y 4/3 and 7/3) moist; massive; hard, friable, 5 percent cobbles; neutral; clear wavy boundary. slightly sticky, slightly plastic; many threads of Bt2—5 to 8 inches; dark brown (7.5YR 4/3) gravelly lime throughout and carbonate coats on rock clay, dark brown (7.5YR 3/3) moist; moderate fragments; 30 percent gravel; 20 percent cobbles; medium prismatic structure parting to strong very strongly effervescent; moderately alkaline. 102 Soil Survey

Range in Characteristics Taxonomic Class: Loamy-skeletal, mixed, superactive Lithic Eutrocryepts Soil temperature: 36 to 44 degrees F Typical Pedon Moisture control section: Between 4 and 12 inches Thickness of the mollic epipedon: 7 to 16 inches Merino very gravelly sandy loam, in an area of Depth to the 2Bk horizon: 17 to 35 inches Merino-Elve-Rock outcrop complex, 25 to 80 percent slopes, in an area of rangeland, 2,600 feet south and A horizon 1,200 feet east of the northwest corner of sec. 1, Hue: 10YR or 2.5Y T. 3 S., R. 13 E.; USGS Squaw Peak topographic Value: 4 or 5 dry; 2 or 3 moist quadrangle (lat. 45o36'15" N.; long. 110o04'09" W.) Chroma: 1 to 3 Texture (less than 2 mm): Loam A—0 to 2 inches; grayish brown (10YR 5/2) very Clay content: 15 to 27 percent gravelly sandy loam, very dark grayish brown Content of rock fragments: 0 to 35 percent—0 to (10YR 3/2) moist; weak fine granular structure; 5 percent stones; 0 to 15 percent cobbles; 0 to soft, very friable, slightly sticky, nonplastic; many 15 percent gravel fine and medium roots; many very fine and fine Reaction: pH 6.1 to 7.8 pores; 40 percent gravel; neutral (pH 6.6); clear smooth boundary. Bt horizons AC—2 to 7 inches; grayish brown (10YR 5/2) very Hue: 10YR, 7.5YR, or 2.5Y gravelly sandy loam, dark grayish brown (10YR Value: 4 to 6 dry; 2 to 4 moist 4/2) moist; weak medium subangular blocky Chroma: 2 to 4 structure parting to weak fine granular; soft, very Texture (less than 2 mm): Clay loam, silty clay friable, slightly sticky, nonplastic; many fine and loam, silty clay, or clay medium roots; many very fine and fine pores; Clay content: 35 to 50 percent 40 percent gravel; 5 percent cobbles; slightly acid Content of rock fragments: 0 to 35 percent—0 to (pH 6.4); clear smooth boundary. 10 percent cobbles; 0 to 25 percent gravel C—7 to 12 inches; light brownish gray (10YR 6/2) Reaction: pH 6.1 to 7.8 very gravelly sandy loam, brown (10YR 4/3) Bk and 2Bk horizons moist; weak fine and medium subangular blocky Hue: 10YR or 2.5Y structure; soft, very friable, nonsticky, nonplastic; Value: 6 to 8 dry; 4 to 7 moist common fine and medium roots; many very fine Chroma: 2 to 4 and fine pores; 40 percent gravel; 5 percent Texture (less than 2 mm): Loam, clay loam, or cobbles; 5 percent stones; moderately acid (pH sandy loam 6.0); abrupt smooth boundary. Clay content: 15 to 35 percent R—12 inches; unweathered bedrock; volcanic Content of rock fragments: 35 to 60 percent—0 to mudflow breccia. 5 percent stones; 5 to 25 percent cobbles; Range in Characteristics 15 to 40 percent gravel Calcium carbonate equivalent: 5 to 15 percent Soil temperature: 38 to 46 degrees F Reaction: pH 7.4 to 8.4 Depth to bedrock: 6 to 20 inches A horizon Hue: 7.5YR, 10YR, or 2.5Y Merino Series Value: 5 or 6 dry; 3 or 4 moist Chroma: 2 or 3 Depth class: Shallow (10 to 20 inches) Texture (less than 2 mm): Sandy loam Drainage class: Well drained Clay content: 12 to 20 percent Permeability: Moderately rapid (2 to 6 inches/hour) Content of rock fragments: 35 to 70 percent—0 to Landform: Mountain 10 percent stones and cobbles; 35 to Parent material: Loamy residuum weathered from 60 percent gravel volcanic breccia Reaction: pH 6.1 to 7.3 Slope range: 8 to 50 percent Elevation range: 5,500 to 7,500 feet AC and C horizons Mean annual precipitation: 20 to 25 inches Hue: 7.5YR, 10YR, or 2.5Y Mean annual air temperature: 37 to 38 degrees F Value: 5 to 7 dry; 4 to 6 moist Frost-free period: 50 to 70 days Chroma: 2 to 4 Sweet Grass County Area, Montana—Part I 103

Texture (less than 2 mm): Sandy loam or loam distinct discontinuous dark brown (10YR 3/3) Clay content: 12 to 20 percent moist; clay films on faces of peds; 5 percent Content of rock fragments: 35 to 80 percent—0 to gravel; neutral (pH 7.2); clear smooth boundary. 10 percent stones and cobbles; 35 to Bk—24 to 60 inches; light brownish gray (10YR 6/2) 70 percent gravel gravelly clay loam, grayish brown (10YR 5/2) Reaction: pH 5.6 to 6.5 moist; weak coarse prismatic structure; slightly hard, friable, moderately sticky, moderately plastic; few very fine roots; common very fine Millerlake Series and fine pores; common fine threads and soft masses of lime; 10 percent gravel; 5 percent Depth class: Very deep (greater than 60 inches) cobbles; strongly effervescent; moderately Drainage class: Well drained alkaline (pH 8.2). Permeability: Moderate (0.6 to 2.0 inches/hour) Landform: Fan, mountain, terrace, and fan on Range in Characteristics mountain Soil temperature: 36 to 42 degrees F Parent material: Loamy alluvium or colluvium Moisture control section: Between 4 and 12 inches Slope range: 4 to 35 percent Thickness of the mollic epipedon: 16 to 20 inches Elevation range: 5,500 to 7,500 feet Depth to the Bk horizon: 20 to 39 inches Mean annual precipitation: 20 to 25 inches Mean annual air temperature: 36 to 38 degrees F A horizon Frost-free period: 50 to 70 days Hue: 7.5YR or 10YR Value: 3 to 5 dry; 2 or 3 moist Taxonomic Class: Fine-loamy, mixed, superactive Chroma: 1 to 3 Pachic Argicryolls Texture (less than 2 mm): Loam Clay content: 20 to 27 percent Typical Pedon Content of rock fragments: 0 to 30 percent—0 to Millerlake loam, in an area of Millerlake-Arrowpeak- 5 percent cobbles; 0 to 25 percent gravel Adel complex, 8 to 35 percent slopes, in an area of Reaction: pH 6.1 to 7.3 rangeland, 1,300 feet south and 1,400 feet west of Bt horizons the northeast corner of sec. 21, T. 2 N., R. 12 E.; Hue: 7.5YR, 10YR, or 2.5Y USGS Raspberry Butte topographic quadrangle Value: 5 or 6 dry; 3 to 5 moist (lat. 45o54'40" N.; long. 110o14'08" W.) Chroma: 2 to 4 A—0 to 7 inches; brown (10YR 5/3) loam, dark brown Texture (less than 2 mm): Clay loam or loam (10YR 3/3) moist; weak fine subangular blocky Clay content: 25 to 35 percent structure parting to moderate fine granular; soft, Content of rock fragments: 0 to 35 percent—0 to very friable, slightly sticky, slightly plastic; few 10 percent cobbles; 0 to 25 percent gravel medium, common fine, and many very fine roots; Reaction: pH 6.1 to 8.4 many very fine and fine pores; 5 percent gravel; Bk horizon neutral (pH 7.0); clear smooth boundary. Hue: 10YR or 2.5Y Bt1—7 to 16 inches; brown (10YR 5/3) clay loam, Value: 6 or 7 dry; 5 or 6 moist dark grayish brown (10YR 4/2) moist; moderate Chroma: 2 to 4 medium subangular blocky structure; slightly Texture (less than 2 mm): Clay loam or loam hard, friable, moderately sticky, moderately Clay content: 20 to 30 percent plastic; common very fine and fine roots; common Content of rock fragments: 10 to 35 percent—0 to very fine and fine pores; common faint 15 percent cobbles; 10 to 20 percent gravel discontinuous dark brown (10YR 3/3) moist; clay Calcium carbonate equivalent: 5 to 15 percent films on faces of peds; 5 percent gravel; neutral Reaction: pH 7.9 to 9.0 (pH 7.2); clear wavy boundary. Bt2—16 to 24 inches; light yellowish brown (2.5Y 6/4) clay loam, grayish brown (2.5Y 5/2) moist; Monaberg Taxadjunct moderate fine subangular blocky structure; slightly hard, friable, moderately sticky, Depth class: Very deep (greater than 60 inches) moderately plastic; common very fine and fine Drainage class: Well drained roots; common very fine and fine pores; few Permeability: Moderate (0.6 to 2.0 inches/hour) 104 Soil Survey

Landform: Fan and mountain slightly hard, friable, slightly sticky, slightly plastic; Parent material: Loamy alluvium or colluvium few very fine and fine roots; common very fine Slope range: 2 to 45 percent and fine pores; distinct continuous dark yellowish Elevation range: 5,500 to 7,500 feet brown (10YR 3/4) moist; clay films on faces of Mean annual precipitation: 20 to 25 inches peds and rock fragments; 20 percent gravel; 10 Mean annual air temperature: 36 to 38 degrees F percent cobbles; neutral (pH 6.8); clear smooth Frost-free period: 50 to 70 days boundary. 2Bt3—37 to 60 inches; brown (10YR 5/3) cobbly clay Taxonomic Class: Fine-loamy, mixed, superactive loam, dark grayish brown (10YR 4/2) moist; weak Pachic Argicryolls fine and medium subangular blocky structure; slightly hard, firm, moderately sticky, moderately The Monaberg soils as mapped in this survey area plastic; few fine roots; common very fine and fine are taxadjunct to the series. They are outside the pores; faint discontinuous dark yellowish brown series range with a mollic epipedon that is 16-inches (10YR 4/4) moist; clay films on rock fragments; or more thick and has a texture finer than loamy fine 15 percent gravel and 15 percent cobbles; slightly sand. Use and management are not significantly acid (pH 6.2). affected. Monaberg series classifies Fine-loamy, mixed, superactive Ustic Argicryolls. Range in Characteristics Typical Pedon Soil temperature: 38 to 42 degrees F Monaberg loam, in an area of Monaberg loam, 4 to Moisture control section: Between 4 and 12 inches 15 percent slopes, in an area of tame pasture, Thickness of the mollic epipedon: 10 to 15 inches 2,200 feet south and 1,300 feet east of the northwest Note: Some pedons have a BC horizon, and some corner of sec. 6, T. 2 N., R. 13 E.; USGS Raspberry pedons do not have a 2Bt horizon. Butte topographic quadrangle (lat. 45o57'12" N.; A horizons long. 110o09'42" W.) Hue: 7.5YR or 10YR A1—0 to 9 inches; very dark grayish brown (10YR Value: 3 or 4 dry; 2 or 3 moist 3/2) loam, very dark gray (10YR 3/1) moist; Chroma: 1 or 2 moderate very fine and fine granular structure; Texture (less than 2 mm): Loam soft, very friable, nonsticky, nonplastic; few Clay content: 18 to 27 percent coarse, common medium, and many very fine Content of rock fragments: 5 to 25 percent—0 to and fine roots; many very fine and fine pores; 5 percent cobbles; 5 to 20 percent gravel 10 percent gravel; neutral (pH 6.6); clear smooth Reaction: pH 5.6 to 7.3 boundary. Bt horizons A2—9 to 15 inches; dark grayish brown (10YR 4/2) Hue: 7.5YR, 10YR, or 2.5Y gravelly loam, very dark grayish brown (10YR Value: 4 to 6 dry; 3 or 4 moist 3/2) moist; moderate very fine and fine granular Chroma: 2 to 4 structure; soft, very friable, nonsticky, nonplastic; Texture (less than 2 mm): Loam, clay loam, or common very fine and fine roots; many very sandy clay loam fine and fine pores; 15 percent gravel; neutral Clay content: 22 to 35 percent (pH 6.8); clear smooth boundary. Content of rock fragments: 10 to 35 percent—0 to Bt1—15 to 25 inches; brown (10YR 5/3) gravelly clay 10 percent cobbles; 10 to 25 percent gravel loam, brown (10YR 4/3) moist; moderate fine Reaction: pH 5.6 to 7.3 subangular blocky structure parting to moderate very fine and fine granular; slightly hard, friable, 2Bt horizon: slightly sticky, moderately plastic; few medium Hue: 7.5YR, 10YR, or 2.5Y and common very fine and fine roots; many very Value: 4 to 6 dry; 3 or 4 moist fine and fine pores; distinct continuous dark Chroma: 2 to 4 yellowish brown (10YR 3/4) moist; clay films on Texture (less than 2 mm): Loam, clay loam, or faces of peds and rock fragments; 20 percent sandy clay loam gravel; neutral (pH 7.2); clear smooth boundary. Clay content: 27 to 35 percent Bt2—25 to 37 inches; brown (10YR 5/3) gravelly clay Content of rock fragments: 15 to 35 percent—0 to loam, dark grayish brown (10YR 4/2) moist; weak 15 percent cobbles; 15 to 20 percent gravel fine and medium subangular blocky structure; Reaction: pH 6.6 to 7.8 Sweet Grass County Area, Montana—Part I 105

Mowbray Series slightly hard, friable, slightly sticky, slightly plastic; few very fine, fine, and coarse roots; common Depth class: Very deep (greater than 60 inches) fine soft masses of lime; 40 percent channers; Drainage class: Well drained 15 percent cobbles; strongly effervescent; Permeability: Moderate (0.6 to 2.0 inches/hour) moderately alkaline (pH 8.0); clear smooth Landform: Landslide and fan on escarpment boundary. Parent material: Gravelly colluvium weathered from BCk—37 to 60 inches; light brownish gray (2.5Y 6/2) calcareous sandstone extremely channery loam, dark grayish brown Slope range: 15 to 60 percent (2.5Y 4/2) moist; massive; moderately hard, Elevation range: 4,200 to 7,900 feet friable, nonsticky, nonplastic; common fine Mean annual precipitation: 15 to 25 inches threads of lime; 40 percent channers; 25 percent Mean annual air temperature: 36 to 45 degrees F cobbles; strongly effervescent; moderately Frost-free period: 50 to 115 days alkaline (pH 8.0). Range in Characteristics Taxonomic Class: Loamy-skeletal, mixed, superactive, frigid Typic Haplustepts Soil temperature: 42 to 47 degrees F Moisture control section: Between 8 and 24 inches Typical Pedon Depth to the Bk horizon: 10 to 20 inches Mowbray channery loam, in an area of Castner- Mowbray-Rock outcrop complex, 25 to 60 percent A horizon slopes, in an area of rangeland, 900 feet north and Hue: 10YR or 2.5Y 700 feet east of the southwest corner of sec. 31, Value: 4 to 6 dry; 3 to 5 moist T. 3 S., R. 13 E.; USGS McLeod Basin topographic Chroma: 2 or 3 quadrangle (lat. 45o36'49" N.; long. 110o10'24" W.) Texture (less than 2 mm): Loam Clay content: 15 to 25 percent A—0 to 6 inches; grayish brown (10YR 5/2) channery Content of rock fragments: 15 to 60 percent—0 to loam, dark grayish brown (10YR 4/2) moist; 10 percent flagstones; 0 to 10 percent cobbles; moderate very fine and fine granular structure; 15 to 45 percent gravel or channers soft, very friable, nonsticky, nonplastic; few Reaction: pH 6.6 to 7.8 coarse and many very fine and fine roots; 25 percent channers; 5 percent cobbles; strongly Bw horizon effervescent; slightly alkaline (pH 7.6); clear Hue: 10YR, 2.5Y, or 5Y smooth boundary. Value: 5 or 6 dry; 4 or 5 moist Bw—6 to 14 inches; grayish brown (2.5Y 5/2) very Chroma: 2 or 3 channery loam, dark grayish brown (2.5Y 4/2) Texture (less than 2 mm): Loam or sandy loam moist; moderate very fine and fine subangular Clay content: 15 to 27 percent blocky structure parting to moderate very fine and Content of rock fragments: 30 to 60 percent—5 to fine granular; soft, friable, slightly sticky, 25 percent flagstones or cobbles; 25 to slightly plastic; common very fine and fine roots; 35 percent gravel or channers 30 percent channers; 5 percent cobbles; slightly Reaction: pH 6.6 to 7.8 effervescent; slightly alkaline (pH 7.6); clear Bk horizons smooth boundary. Hue: 10YR, 2.5Y, or 5Y Bk1—14 to 29 inches; grayish brown (2.5Y 5/2) very Value: 5 or 6 dry; 4 or 5 moist channery sandy loam, very dark grayish brown Chroma: 2 or 3 (2.5Y 4/2) moist; weak fine subangular blocky Texture (less than 2 mm): Loam or sandy loam structure parting to weak very fine and fine Clay content: 15 to 27 percent granular; soft, friable, nonsticky, nonplastic; Content of rock fragments: 40 to 80 percent— common very fine and fine roots; common fine 10 to 35 percent flagstones or cobbles; 30 to and medium soft masses of lime; 25 percent 45 percent gravel or channers channers; 20 percent cobbles; strongly Calcium carbonate equivalent: 5 to 15 percent effervescent; moderately alkaline (pH 7.8); clear Reaction: pH 7.4 to 8.4 smooth boundary. Bk2—29 to 37 inches; grayish brown (2.5Y 5/2) very BCk horizon channery loam, dark grayish brown (2.5Y 4/2) Hue: 10YR, 2.5Y, or 5Y moist; weak medium subangular blocky structure; Value: 5 or 6 dry; 4 or 5 moist 106 Soil Survey

Chroma: 2 or 3 blocky structure parting to moderate very fine Texture (less than 2 mm): Loam or sandy loam and fine granular; soft, friable, slightly sticky, Clay content: 15 to 27 percent slightly plastic; common very fine and fine roots; Content of rock fragments: 40 to 80 percent— 30 percent channers; 5 percent cobbles; slightly 10 to 35 percent flagstones or cobbles; 30 to effervescent; slightly alkaline (pH 7.6); clear 45 percent gravel or channers smooth boundary. Calcium carbonate equivalent: 5 to 15 percent Bk1—14 to 29 inches; grayish brown (2.5Y 5/2) very Reaction: pH 7.4 to 8.4 channery sandy loam, very dark grayish brown (2.5Y 4/2) moist; weak fine subangular blocky structure parting to weak very fine and fine Mowbray Taxadjunct granular; soft, friable, nonsticky, nonplastic; common very fine and fine roots; common fine Depth class: Very deep (greater than 60 inches) and medium soft masses of lime; 25 percent Drainage class: Well drained channers; 20 percent cobbles; strongly Permeability: Moderate (0.6 to 2.0 inches/hour) effervescent; moderately alkaline (pH 7.8); clear Landform: Hills and escarpments smooth boundary. Parent material: Gravelly colluvium weathered from Bk2—29 to 37 inches; grayish brown (2.5Y 5/2) very calcareous sandstone channery loam, dark grayish brown (2.5Y 4/2) Slope range: 15 to 35 percent moist; weak medium subangular blocky structure; Elevation range: 6,000 to 7,500 feet slightly hard, friable, slightly sticky, slightly plastic; Mean annual precipitation: 20 to 25 inches few very fine, fine, and coarse roots; common Mean annual air temperature: 36 to 39 degrees F fine soft masses of lime; 40 percent channers; Frost-free period: 50 to 70 days 15 percent cobbles; strongly effervescent; moderately alkaline (pH 8.0); clear smooth Taxonomic Class: Loamy-skeletal, mixed, boundary. superactive Ustic Eutrocryepts BCk—37 to 60 inches; light brownish gray (2.5Y 6/2) extremely channery loam, dark grayish brown The Mowbray soils as mapped in map unit 430E are (2.5Y 4/2) moist; massive; moderately hard, a taxadjunct to the series. They are outside the series friable, nonsticky, nonplastic; common fine range with a cryic temperature regime, and the mean threads of lime; 40 percent channers; 25 percent summer soil temperature at a depth of 20 inches from cobbles; strongly effervescent; moderately the soil surface is lower than 15 degrees C. Use and alkaline (pH 8.0). management are not significantly affected. Mowbray series classifies Loamy-skeletal, mixed, superactive, Range in Characteristics frigid Typic Haplustepts. Soil temperature: 38 to 41 degrees F Typical Pedon Moisture control section: Between 8 and 24 inches Depth to the Bk horizon: 10 to 20 inches Mowbray channery loam, in an area of Castner- Mowbray-Rock outcrop complex, 25 to 60 percent A horizon slopes, in an area of rangeland, 900 feet north and Hue: 10YR or 2.5Y 700 feet east of the southwest corner of sec. 31, Value: 4 to 6 dry; 3 to 5 moist T. 3 S., R. 13 E.; USGS McLeod Basin topographic Chroma: 2 or 3 quadrangle (lat. 45o36'49" N.; long. 110o10'24" W.) Texture (less than 2 mm): Loam Clay content: 15 to 25 percent A—0 to 6 inches; grayish brown (10YR 5/2) channery Content of rock fragments: 15 to 60 percent—0 to loam, dark grayish brown (10YR 4/2) moist; 10 percent flagstones; 0 to 10 percent cobbles; moderate very fine and fine granular structure; 15 to 45 percent gravel or channers soft, very friable, nonsticky, nonplastic; many very Reaction: pH 6.6 to 7.8 fine and fine, few coarse roots; 25 percent channers; 5 percent cobbles; strongly Bw horizon effervescent; slightly alkaline (pH 7.6); clear Hue: 10YR, 2.5Y, or 5Y smooth boundary. Value: 5 or 6 dry; 4 or 5 moist Bw—6 to 14 inches; grayish brown (2.5Y 5/2) very Chroma: 2 or 3 channery loam, dark grayish brown (2.5Y 4/2) Texture (less than 2 mm): Loam or sandy loam moist; moderate very fine and fine subangular Clay content: 15 to 27 percent Sweet Grass County Area, Montana—Part I 107

Content of rock fragments: 30 to 60 percent—5 to A1—0 to 2 inches; dark grayish brown (10YR 4/2) 25 percent flagstones or cobbles; 25 to loam, very dark grayish brown (10YR 3/2) moist; 35 percent gravel or channers moderate fine granular structure; soft, very Reaction: pH 6.6 to 7.8 friable, nonsticky, nonplastic; many very fine to medium roots; many very fine and fine pores; Bk horizons 10 percent gravel; neutral (pH 7.2); abrupt Hue: 10YR, 2.5Y, or 5Y smooth boundary. Value: 5 or 6 dry; 4 or 5 moist A2—2 to 12 inches; dark grayish brown (10YR 4/2) Chroma: 2 or 3 gravelly loam, very dark grayish brown (10YR Texture (less than 2 mm): Loam or sandy loam 3/2) moist; weak fine and medium subangular Clay content: 15 to 27 percent blocky structure; soft, very friable, nonsticky, Content of rock fragments: 40 to 80 percent— nonplastic; many very fine and fine roots; many 10 to 35 percent flagstones or cobbles; 30 to very fine and fine pores; 15 percent gravel; 45 percent gravel or channers 5 percent cobbles; neutral (pH 7.2); abrupt Calcium carbonate equivalent: 5 to 15 percent smooth boundary. Reaction: pH 7.4 to 8.4 2C1—12 to 28 inches; grayish brown (10YR 5/2) BCk horizon very gravelly loamy sand, dark grayish brown Hue: 10YR, 2.5Y, or 5Y (10YR 4/2) moist; single grain; loose, nonsticky, Value: 5 or 6 dry; 4 or 5 moist nonplastic; few very fine and fine roots; Chroma: 2 or 3 30 percent gravel; 10 percent cobbles; few Texture (less than 2 mm): Loam or sandy loam distinct carbonate coats on rock fragments; Clay content: 15 to 27 percent slightly effervescent; moderately alkaline Content of rock fragments: 40 to 80 percent— (pH 8.2); clear smooth boundary. 10 to 35 percent flagstones or cobbles; 30 to 2C2—28 to 60 inches; grayish brown (10YR 5/2) 45 percent gravel or channers extremely gravelly sand, dark grayish brown Calcium carbonate equivalent: 5 to 15 percent (10YR 4/2) moist; single grain; loose, nonsticky, Reaction: pH 7.4 to 8.4 nonplastic; 45 percent gravel; 15 percent cobbles; common distinct carbonate coats on rock fragments; strongly effervescent; moderately Nesda Series alkaline (pH 8.2). Range in Characteristics Depth class: Very deep (greater than 60 inches) Drainage class: Well drained Soil temperature: 41 to 47 degrees F Permeability: In the upper 0 to 12 inches = moderate Moisture control section: Between 12 and 35 inches (0.6 to 2.0 inches/hour); below this depth = rapid Thickness of the mollic epipedon: 10 to 16 inches (6 to 20 inches/hour) Depth to the 2C horizon: 10 to 20 inches Landform: Flood plain A horizons Parent material: Sandy and gravelly alluvium Hue: 10YR, 2.5Y, or 5Y Slope range: 0 to 4 percent Value: 3 to 5 dry; 2 or 3 moist Elevation range: 3,750 to 6,200 feet Chroma: 1 to 3 Mean annual precipitation: 10 to 20 inches Texture (less than 2 mm): Loam Mean annual air temperature: 39 to 46 degrees F Clay content: 10 to 20 percent Frost-free period: 70 to 130 days Content of rock fragments: 0 to 60 percent—0 to 15 percent stones and cobbles; 0 to 45 percent Taxonomic Class: Sandy-skeletal, mixed, frigid gravel Fluventic Haplustolls Calcium carbonate equivalent: 1 to 5 percent Typical Pedon Reaction: pH 6.6 to 7.8 Nesda loam, in an area of Nesda-McIlwaine loams, 2C horizons 0 to 2 percent slopes, in an area of deciduous forest, Hue: 10YR, 2.5Y, or 5Y 200 feet north and 300 feet west of the southeast Value: 4 to 7 dry; 3 to 5 moist corner of sec. 15, T. 2 N., R. 13 E.; USGS Grosfield Chroma: 2 to 4 Ranch topographic quadrangle (lat. 45o54'58" N.; Texture (less than 2 mm): Loamy sand or sand long. 110o05'04" W.) Clay content: 0 to 10 percent 108 Soil Survey

Content of rock fragments: 35 to 80 percent—0 to Ag—11 to 22 inches; very dark gray (5Y 3/1) loam, 15 percent stones and cobbles; 35 to dark gray (5Y 4/1) dry; common fine and medium 60 percent gravel prominent olive (5Y 5/6) moist, redox Calcium carbonate equivalent: 1 to 5 percent concentrations; weak fine granular structure; Reaction: pH 7.4 to 8.4 moderately hard, very friable, slightly sticky, slightly plastic; common very fine and fine roots; common very fine and fine pores; neutral Newtman Taxadjunct (pH 6.6); gradual smooth boundary. Cg1—22 to 36 inches; very dark gray (5Y 3/1) loam, Depth class: Very deep (greater than 60 inches) gray (5Y 5/1) dry; common fine and medium Drainage class: Very poorly drained prominent olive (5Y 5/6) moist, redox Permeability: Moderately slow (0.2 to 0.6 inch/hour) concentrations; massive; moderately hard, very Landform: Flood plain, depression on terrace friable, slightly sticky, slightly plastic; few fine Parent material: Alluvium roots; 5 percent gravel; neutral (pH 6.8); gradual Slope range: 0 to 2 percent smooth boundary. Elevation range: 3,750 to 6,000 feet 2Cg2—36 to 60 inches; dark gray (5Y 4/1) very Mean annual precipitation: 10 to 19 inches gravelly loam, gray (5Y 6/1) dry; common fine Mean annual air temperature: 43 to 46 degrees F and medium prominent olive (5Y 5/6) moist, Frost-free period: 85 to 125 days redox concentrations; massive; moderately hard, very friable, slightly sticky, slightly plastic; Taxonomic Class: Fine-loamy, mixed, superactive, 35 percent gravel; 5 percent cobbles; neutral nonacid, frigid Histic Endoaquolls (pH 7.2). Range in Characteristics Newtman soils as mapped in this survey area are taxadjunct to the series. They are outside the series Soil temperature: 39 to 43 degrees F range with a mollic epipedon directly below the histic Moisture control section: Between 4 and 12 inches epipedon and lower reaction and calcium carbonate Thickness of the histic epipedon: 8 to 16 inches equivalent in the 10- to 20-inch calcareous and Depth to the 2C horizon: 24 to 40 inches reaction class control section. Use and management Depth to the seasonal high water table: +6 to are not significantly affected. Newtman series 12 inches classifies Fine-loamy, mixed, superactive, calcareous, Oa horizons frigid Histic Humaquepts. Hue: 10YR or N Typical Pedon Value: 2 or 3 moist Chroma: 0 or 1 Newtman muck, in an area of Newtman muck, 0 to Reaction: pH 6.1 to 7.8 2 percent slopes, in an area of rangeland, 1,300 feet south and 600 feet east of the northwest corner of A horizon sec. 3, T. 4 N., R. 13 E.; USGS Melville NW Hue: 10YR, 5Y, or N topographic quadrangle (lat. 46o07'46" N.; long. Value: 3 to 5 dry; 2 or 3 moist 109o58'29" W.) (Colors are for moist soil unless Chroma: 0 or 1 otherwise noted.) Redox concentrations: None to common; chroma of 4 or 6 Oa1—0 to 4 inches; black (10YR 2/1) muck, very Texture (less than 2 mm): Loam, silt loam, or clay dark gray (10YR 3/1) dry; about 30 percent fibers loam unrubbed, 10 percent rubbed; soft, very friable, Clay content: 20 to 35 percent nonsticky, nonplastic; many fine and medium Content of rock fragments: 0 to 15 percent gravel roots; slightly acid (pH 6.4); clear smooth Reaction: pH 6.6 to 7.8 boundary. Oa2—4 to 11 inches; black (10YR 2/1) muck, very Cg horizon dark gray (10YR 3/1) dry; about 25 percent fibers Hue: 5Y or N unrubbed, 5 percent rubbed; soft, very friable, Value: 4 to dry; 2 to 6 moist nonsticky, nonplastic; many fine and medium Chroma: 0 to 2 roots; slightly acid (pH 6.4); clear smooth Redox concentrations: None to common; chroma boundary. of 4 or 6 Sweet Grass County Area, Montana—Part I 109

Texture (less than 2 mm): Clay loam, silt loam, or and many very fine and fine roots; many very fine loam and fine pores; 5 percent gravel; 5 percent Clay content: 25 to 35 percent cobbles; strongly effervescent; slightly alkaline Content of rock fragments: 0 to 15 percent gravel (pH 7.4); clear smooth boundary. Calcium carbonate equivalent: 0 to 10 percent A2—9 to 13 inches; very dark gray (10YR 3/1) loam, Reaction: pH 6.6 to 7.8 black (10YR 2/1) moist; few fine distinct dark yellowish brown (10YR 4/6) moist, redox 2Cg horizon concentrations; moderate medium subangular Hue: 5Y, 2.5Y, or N blocky structure; moderately hard, friable, slightly Value: 4 to 6 dry; 2 to 5 moist sticky, slightly plastic; common medium and many Chroma: 0 to 2 very fine and fine roots; many very fine and fine Redox concentrations: None to many; chroma of pores; 5 percent gravel; 5 percent cobbles; 4 or 6 strongly effervescent; slightly alkaline (pH 7.4); Redox depletions: None to common; chroma of 0 clear smooth boundary. or 1 A3—13 to 21 inches; very dark gray (10YR 3/1) clay Texture (less than 2 mm): Clay loam, sandy loam, loam, black (10YR 2/1) moist; many fine distinct or loam dark yellowish brown (10YR 4/6) moist, redox Clay content: 18 to 30 percent concentrations; moderate medium subangular Content of rock fragments: 25 to 60 percent—5 to blocky structure; moderately hard, friable, 15 percent cobbles; 20 to 45 percent gravel moderately sticky, moderately plastic; common Calcium carbonate equivalent: 0 to 10 percent medium and many very fine and fine roots; Reaction: pH 6.6 to 7.8 common very fine and fine pores; 5 percent gravel; 5 percent cobbles; strongly effervescent; slightly alkaline (pH 7.4); clear smooth boundary. Novary Series A4—21 to 29 inches; very dark grayish brown (10YR 3/2) gravelly clay loam, very dark brown (10YR Depth class: Very deep (greater than 60 inches) 2/2) moist; common fine and medium distinct Drainage class: Poorly drained dark yellowish brown (10YR 4/6) moist, redox Permeability: Moderate (0.6 to 2.0 inches/hour) concentrations; weak medium subangular blocky Landform: Flood plain, pothole on landslide, swale on structure; moderately hard, friable, moderately landslide, and drainageway on mountain sticky, moderately plastic; common very fine and Parent material: Loamy alluvium fine roots; common very fine and fine pores; Slope range: 0 to 6 percent 10 percent gravel; 5 percent cobbles; slightly Elevation range: 5,500 to 7,500 feet effervescent; slightly alkaline (pH 7.4); clear Mean annual precipitation: 20 to 25 inches smooth boundary. Mean annual air temperature: 36 to 38 degrees F Cgk1—29 to 38 inches; grayish brown (10YR 5/2) Frost-free period: 50 to 70 days gravelly loam, very dark grayish brown (10YR 4/2) moist; few fine and medium faint olive (5Y Taxonomic Class: Fine-loamy, mixed, superactive, 5/4) moist, redox concentrations; massive; calcareous Cumulic Cryaquolls moderately hard, friable, slightly sticky, slightly plastic; common very fine and fine roots; common Typical Pedon very fine and fine pores; few carbonate coats on rock fragments; 20 percent gravel; 5 percent Novary loam, in an area of Mowbray-Bridger-Novary cobbles; strongly effervescent; slightly alkaline complex, 0 to 35 percent slopes, in an area of (pH 7.4); clear smooth boundary. rangeland, 2,000 feet south and 100 feet east of Cgk2—38 to 49 inches; grayish brown (2.5Y 5/2) the northwest corner of sec. 11, T. 3 S., R. 12 E.; cobbly clay loam, dark grayish brown (2.5Y 4/2) USGS McLeod Basin topographic quadrangle moist; common fine distinct olive (5Y 5/6) moist, (lat. 45o35'25" N.; long. 110o12'58" W.) redox concentrations; massive; moderately hard, A1—0 to 9 inches; very dark gray (10YR 3/1) loam, friable, moderately sticky, moderately plastic; few black (10YR 2/1) moist; weak medium very fine and fine roots; common carbonate coats subangular blocky structure parting to moderate on rock fragments; 10 percent gravel; 10 percent fine and medium granular; slightly hard, friable, cobbles; violently effervescent; slightly alkaline slightly sticky, slightly plastic; common medium (pH 7.6); clear smooth boundary. 110 Soil Survey

Cgk3—49 to 60 inches; grayish brown (2.5Y 5/2) Content of rock fragments: 5 to 35 percent—0 to cobbly clay loam, dark grayish brown (2.5Y 4/2) 15 percent stones and cobbles; 5 to 20 percent moist; common fine distinct olive (5Y 5/6) moist, gravel redox concentrations; massive; moderately hard, Calcium carbonate equivalent: 1 to 15 percent friable, moderately sticky, moderately plastic; Reaction: pH 7.4 to 8.4 common carbonate coats on rock fragments, common fine and medium masses of lime; 10 percent gravel; 15 percent cobbles; strongly Overfelt Series effervescent; slightly alkaline (pH 7.4). Depth class: Very deep (greater than 60 inches) Range in Characteristics Drainage class: Well drained Permeability: In the upper 0 to 27 inches = very slow Soil temperature: 38 to 45 degrees F (less than 0.6 inch/hour) Moisture control section: Between 4 and 12 inches Landform: Fan, stream terrace, and terrace Thickness of the mollic epipedon: 20 to 40 inches Parent material: Clayey over gravelly alluvium Depth to the seasonal high water table: 6 to Slope range: 0 to 4 percent 24 inches Elevation range: 4,200 to 6,000 feet Note: Some pedons have a 2Cg horizon below a Mean annual precipitation: 15 to 19 inches depth of 40 inches. Mean annual air temperature: 43 to 45 degrees F A1 horizon Frost-free period: 85 to 115 days Hue: 10YR, 2.5Y, 5Y, or N Value: 3 to 5 dry; 2 or 3 moist Taxonomic Class: Clayey over loamy-skeletal, Chroma: 0 to 2 smectitic over mixed, superactive, frigid Vertic Texture (less than 2 mm): Loam Argiustolls Clay content: 18 to 27 percent Typical Pedon Content of rock fragments: 0 to 35 percent—0 to 10 percent stones and cobbles; 0 to 25 percent Overfelt clay loam, in an area of Overfelt-Roy gravel complex, 0 to 4 percent slopes, in an area of pasture, Calcium carbonate equivalent: 1 to 15 percent 2,000 feet north and 2,400 feet east of the southwest Reaction: pH 6.6 to 8.4 corner of sec. 8, T. 1 S., R. 16 E.; USGS Greycliff topographic quadrangle (lat. 45o45'33" N.; long. A2, A3, and A4 horizons 109o46'41" W.) Hue: 10YR, 2.5Y, 5Y, or N Value: 3 to 5 dry; 2 or 3 moist A—0 to 8 inches; brown (7.5YR 4/2) clay loam, dark Chroma: 0 to 2 brown (7.5YR 3/2) moist; weak fine subangular Redox concentrations: Few to many; chroma of 4 blocky structure parting to moderate fine or 6 granular; slightly hard, friable, slightly sticky, Texture (less than 2 mm): Loam, clay loam, or silt slightly plastic; few medium and common fine loam roots; many very fine and fine pores; 2 percent Clay content: 18 to 35 percent gravel; 3 percent cobbles; neutral (pH 7.0); abrupt Content of rock fragments: 0 to 35 percent—0 to smooth boundary. 10 percent stones and cobbles; 0 to 25 percent Bt1—8 to 16 inches; brown (7.5YR 5/2) clay, dark gravel brown (7.5YR 4/2) moist; moderate medium Calcium carbonate equivalent: 1 to 15 percent prismatic structure parting to strong medium Reaction: pH 6.6 to 8.4 subangular blocky; very hard, firm, very sticky, Cgk horizons very plastic; common fine roots; common very Hue: N, 10YR, 2.5Y, or 5Y fine and fine pores; common pressure faces and 1 1 Value: 5 or 6 dry; 4 or 5 moist cracks /4- to /2-inch wide; many distinct Chroma: 0 to 2 continuous grayish brown (10YR 5/2) moist; clay Redox concentrations: None to many; chroma of films on faces of peds and lining pores; 5 percent 4 or 6 gravel; neutral (pH 7.2); clear smooth boundary. Texture (less than 2 mm): Clay loam, silt loam, or Bt2—16 to 27 inches; brown (7.5YR 5/2) clay, dark loam brown (7.5YR 4/2) moist; moderate medium Clay content: 18 to 35 percent prismatic structure parting to strong medium Sweet Grass County Area, Montana—Part I 111

subangular blocky; very hard, firm, very sticky, Chroma: 2 to 4 very plastic; common fine roots; common very Texture (less than 2 mm): Sandy clay loam, clay fine and fine pores; common pressure faces and loam, loam, or sandy loam 1 1 cracks /4- to /2-inch wide; many distinct Clay content: 15 to 35 percent continuous grayish brown (10YR 5/2) moist; clay Content of rock fragments: 35 to 70 percent—0 to films on faces of peds and lining pores; 5 percent 5 percent stones; 5 to 20 percent cobbles; gravel; slightly alkaline (pH 7.4); clear smooth 30 to 45 percent gravel boundary. Calcium carbonate equivalent: 5 to 15 percent 2Bk1—27 to 42 inches; brown (10YR 5/3) very Reaction: pH 7.4 to 8.4 gravelly sandy clay loam, dark brown (10YR 4/3) 3Bk2 horizon moist; weak coarse prismatic structure; slightly Hue: 7.5YR, 10YR, or 2.5Y hard, very friable, slightly sticky, slightly plastic; Value: 5 to 7 dry; 4 to 6 moist few very fine and fine roots; common fine and Chroma: 2 to 4 medium pores; many distinct carbonate coats on Texture (less than 2 mm): Coarse sand, sand, undersides of rock fragments; 35 percent gravel; loamy sand, or loamy coarse sand 15 percent cobbles; 5 percent stones; strongly Clay content: 1 to 10 percent effervescent; moderately alkaline (pH 8.4); Content of rock fragments: 35 to 80 percent—0 to gradual smooth boundary. 10 percent stones; 5 to 25 percent cobbles; 3Bk2—42 to 60 inches; pale brown (10YR 6/3) very 30 to 45 percent gravel gravelly coarse sand, brown (10YR 5/3) moist; Calcium carbonate equivalent: 1 to 10 percent single grain; loose, nonsticky, nonplastic; few faint Reaction: pH 7.4 to 8.4 carbonate coats on undersides of rock fragments; 35 percent gravel; 15 percent cobbles; 5 percent stones; strongly effervescent; moderately alkaline Perma Series (pH 8.4). Depth class: Very deep (greater than 60 inches) Range in Characteristics Drainage class: Somewhat excessively drained Soil temperature: 42 to 47 degrees F Permeability: Moderate (0.6 to 2.0 inches/hour) Moisture control section: Between 4 and 12 inches Landform: Fan, hill, landslide, stream terrace, and fan Thickness of the mollic epipedon: 7 to 15 inches on escarpment Depth to the 2Bk horizon: 20 to 36 inches Parent material: Gravelly alluvium or colluvium Depth to the 3Bk horizon: 40 to over 60 inches Slope range: 0 to 60 percent Elevation range: 3,900 to 6,200 feet A horizon Annual precipitation: 15 to 20 inches Hue: 7.5YR or 10YR Mean annual air temperature: 43 to 45 degrees F Value: 4 or 5 dry; 2 or 3 moist Frost-free period: 70 to 115 days Chroma: 2 or 3 Texture (less than 2 mm): Clay loam Taxonomic Class: Loamy-skeletal, mixed, Clay content: 27 to 40 percent superactive, frigid Typic Haplustolls Content of rock fragments: 0 to 25 percent—0 to 5 percent cobbles; 0 to 20 percent gravel Typical Pedon Reaction: pH 6.6 to 7.8 Bt horizons Perma cobbly loam, in an area of Perma, stony- Hue: 7.5YR or 10YR Whitlash, very stony complex, 15 to 35 percent Value: 5 or 6 dry; 4 or 5 moist slopes, in an area of rangeland, 1,520 feet north and Chroma: 2 to 4 2,590 feet east of the southwest corner of sec. 28, Texture (less than 2 mm): Clay or silty clay T. 7 N., R. 4 W.; Jefferson County, Montana. Clay content: 40 to 60 percent A1—0 to 7 inches; dark grayish brown (10YR 4/2) Content of rock fragments: 0 to 15 percent—0 to cobbly loam, very dark grayish brown (10YR 3/2) 5 percent cobbles; 0 to 10 percent gravel moist; moderate fine granular structure; soft, very Reaction: pH 6.6 to 7.8 friable, slightly sticky, slightly plastic; many very 2Bk1 horizon fine and fine roots; 15 percent angular cobbles; Hue: 7.5YR or 10YR 15 percent angular gravel; neutral (pH 6.6); clear Value: 5 to 7 dry; 4 to 6 moist wavy boundary. 112 Soil Survey

A2—7 to 13 inches; brown (10YR 4/3) very gravelly Content of rock fragments: 35 to 85 percent—0 to loam, dark brown (10YR 3/3) moist; moderate 50 percent stones and cobbles; 25 to medium subangular blocky structure; slightly 65 percent gravel hard, very friable, slightly sticky, slightly plastic; Reaction: pH 6.6 to 7.8 many very fine and fine roots; many very fine BC horizon pores; 10 percent angular cobbles; 45 percent Hue: 10YR or 7.5YR rounded gravel; neutral (pH 6.8); clear wavy Value: 4 to 7 dry; 3 to 5 moist boundary. Chroma: 2 to 4 Bw1—13 to 28 inches; brown (10YR 5/3) very Texture (less than 2 mm): Loam, loamy sand, or gravelly loam, brown (10YR 4/3) moist; moderate sandy loam fine and medium subangular blocky structure; Clay content: 0 to 15 percent slightly hard, very friable, slightly sticky, slightly Content of rock fragments: 60 to 85 percent— plastic; many very fine and fine roots; common 10 to 25 percent stones and cobbles; 50 to very fine pores; 15 percent angular cobbles; 60 percent gravel 35 percent angular gravel; neutral (pH 7.0); Reaction: pH 6.6 to 7.8 gradual wavy boundary. Bw2—28 to 44 inches; pale brown (10YR 6/3) very gravelly sandy loam, brown (10YR 4/3) moist; Pianohill Series weak fine subangular blocky structure; slightly hard, very friable, nonsticky, nonplastic; common Depth class: Moderately deep (20 to 40 inches) very fine and fine roots; common very fine pores; Drainage class: Well drained 15 percent angular cobbles; 40 percent angular Permeability: Moderate (0.6 to 2.0 inches/hour) gravel; slightly alkaline (pH 7.4); gradual wavy Landform: Hill and structural bench boundary. Parent material: Residuum weathered from tuff BC—44 to 60 inches; very pale brown (10YR 7/3) breccia extremely gravelly sandy loam, grayish brown Slope range: 4 to 35 percent (10YR 5/2) moist; massive; slightly hard, very Elevation range: 4,200 to 6,200 feet friable, nonsticky, nonplastic; few very fine roots; Mean annual precipitation: 15 to 20 inches 20 percent angular cobbles; 50 percent angular Mean annual air temperature: 39 to 45 degrees F gravel; common faint carbonate coats on Frost-free period: 70 to 115 days undersides of rock fragments; slightly alkaline (pH 7.4). Taxonomic Class: Fine-loamy, mixed, superactive, frigid Typic Argiustolls Range in Characteristics Typical Pedon Soil temperature: 38 to 42 degrees F Pianohill loam, in an area of Whitlash-Pianohill Moisture control section: Between 8 and 24 inches complex, 4 to 15 percent slopes, in an area of Thickness of the mollic epipedon: 10 to 15 inches rangeland, 800 feet north and 2,100 feet east of A horizons the southwest corner of sec. 23, T. 2 S., R. 15 E.; Value: 4 or 5 dry; 2 or 3 moist USGS Packsaddle Butte topographic quadrangle Chroma: 2 or 3 (lat. 45o38'27" N.; long. 109o50'28" W.) Clay content: 7 to 27 percent A1—0 to 6 inches; grayish brown (10YR 5/2) loam, Content of rock fragments: 15 to 60 percent—0 to very dark grayish brown (10YR 3/2) moist; weak 30 percent stones and cobbles; 10 to fine granular structure; soft, very friable, slightly 50 percent gravel sticky, slightly plastic; many very fine and fine Reaction: pH 6.1 to 7.3 roots; many very fine and fine pores; 5 percent Surface stones or boulders: .01 to 3 percent cobbles; slightly acid (pH 6.4); abrupt smooth Bw horizons boundary. Hue: 10YR or 7.5YR A2—6 to 10 inches; brown (10YR 5/3) loam, dark Value: 4 to 6 dry; 3 to 5 moist brown (10YR 3/3) moist; weak medium Chroma: 2 to 4 subangular blocky structure parting to weak fine Texture (less than 2 mm): Loam or sandy loam and medium granular; soft, very friable, slightly Clay content: 7 to 20 percent sticky, slightly plastic; many very fine and fine Sweet Grass County Area, Montana—Part I 113

roots; many very fine and fine pores; slightly acid Bt1 horizon (pH 6.2); clear smooth boundary. Hue: 10YR or 2.5Y Bw—10 to 16 inches; pale brown (10YR 6/3) loam, Value: 5 or 6 dry; 4 or 5 moist brown (10YR 4/3) moist; weak medium Chroma: 3 or 4 subangular blocky structure; soft, very friable, Texture (less than 2 mm): Loam, clay loam, or slightly sticky, slightly plastic; many very fine and sandy clay loam fine roots; many very fine and fine pores; neutral Clay content: 20 to 35 percent (pH 6.6); clear smooth boundary. Content of rock fragments: 0 to 15 percent—0 to Bt1—16 to 21 inches; pale brown (10YR 6/3) clay 5 percent cobbles; 0 to 10 percent gravel loam, brown (10YR 5/3) moist; moderate medium Reaction: pH 6.1 to 7.3 subangular blocky structure; slightly hard, friable, Bt2 horizon moderately sticky, moderately plastic; many very Hue: 10YR or 2.5Y fine and fine roots; many very fine and fine pores; Value: 5 to 7 dry; 4 to 6 moist common faint discontinuous dark yellowish brown Chroma: 3 or 4 (10YR 4/4) moist; clay films on faces of peds and Texture (less than 2 mm): Loam, clay loam, or lining pores; 5 percent gravel; neutral (pH 6.6); sandy clay loam clear smooth boundary. Clay content: 20 to 35 percent Bt2—21 to 29 inches; very pale brown (10YR 7/4) Content of rock fragments: 0 to 35 percent—0 to loam, yellowish brown (10YR 6/4) moist; 10 percent cobbles; 0 to 25 percent gravel moderate medium subangular blocky structure; Reaction: pH 6.1 to 7.3 soft, friable, moderately sticky, moderately plastic; common very fine and fine roots; common very fine and fine pores; few faint discontinuous dark Pintlar Series yellowish brown (10YR 4/4) moist; clay films on faces of peds and lining pores; 12 percent gravel; Depth class: Very deep (greater than 60 inches) neutral (pH 6.8); abrupt smooth boundary. Drainage class: Well drained R—29 inches; volcanic mudflow breccia bedrock. Permeability: Moderate (0.6 to 2.0 inches/hour) Landform: Swale on mountain Range in Characteristics Parent material: Loamy alluvium Slope range: 4 to 35 percent Soil temperature: 42 to 47 degrees F Elevation range: 5,500 to 7,500 feet Moisture control section: Between 4 and 12 inches Mean annual precipitation: 20 to 25 inches Thickness of the mollic epipedon: 7 to 15 inches Mean annual air temperature: 36 to 38 degrees F Depth to bedrock: 20 to 40 inches Frost-free period: 50 to 70 days Note: Some pedons have a BC horizon, and some pedons do not have a Bw horizon. Taxonomic Class: Fine-loamy, mixed, superactive A horizons Ustic Palecryolls Hue: 10YR or 2.5Y Typical Pedon Value: 3 to 5 dry; 2 or 3 moist Chroma: 2 or 3 Pintlar loam, in an area of Pintlar-Bridger complex, Texture (less than 2 mm): Loam 4 to 35 percent slopes, in an area of deciduous Clay content: 15 to 27 percent forest, 1,900 feet north and 100 feet east of the Content of rock fragments: 0 to 15 percent—0 to southwest corner of sec. 13, T. 3 S., R. 13 E.; 5 percent cobbles; 0 to 10 percent gravel USGS Squaw peak topographic quadrangle Reaction: pH 6.1 to 7.3 (lat. 45o34'23" N.; long. 110o04'24" W.) Bw horizon: A1—0 to 7 inches; very dark gray (10YR 3/1) loam, Hue: 10YR or 2.5Y black (10YR 2/1) moist; strong very fine and fine Value: 5 or 6 dry; 3 to 5 moist granular structure; soft, very friable, slightly sticky, Chroma: 2 to 4 slightly plastic; common medium and coarse and Texture (less than 2 mm): Loam many very fine and fine roots; many very fine and Clay content: 15 to 27 percent fine pores; neutral (pH 6.8); clear smooth Content of rock fragments: 0 to 15 percent—0 to boundary. 5 percent cobbles; 0 to 10 percent gravel A2—7 to 15 inches; dark gray (10YR 4/1) loam, very Reaction: pH 6.1 to 7.3 dark gray (10YR 3/1) moist; weak fine and 114 Soil Survey

medium subangular blocky structure; slightly Content of rock fragments: 0 to 20 percent—0 to hard, friable, slightly sticky, slightly plastic; 5 percent stones and cobbles; 0 to 15 percent common very fine and fine roots; few fine and gravel medium and many very fine pores; neutral Reaction: pH 5.6 to 7.3 (pH 6.8); clear wavy boundary. E/Bt horizon E—15 to 31 inches; light brownish gray (10YR 6/2) Hue: 5YR, 7.5YR, or 10YR gravelly loam, dark grayish brown (10YR 4/2) Value: E part—5 to 7, Bt part—4 to 6 dry; E moist; weak medium and coarse subangular part—4 or 5, Bt part—3 to 5 moist blocky structure; slightly hard, friable, slightly Chroma: 2 to 4 sticky, slightly plastic; common very fine and fine Texture (less than 2 mm): Loam, silt loam, or clay roots; few medium and common very fine and loam fine pores; 15 percent gravel; neutral (pH 6.8); Clay content: 15 to 35 percent clear wavy boundary. Content of rock fragments: 0 to 20 percent—0 to E/Bt—31 to 36 inches; E part (70 percent) light 5 percent cobbles; 0 to 15 percent gravel brownish gray (10YR 6/2) gravelly loam, dark Reaction: pH 5.6 to 7.3 grayish brown (10YR 4/2) moist tongues; Bt part (30 percent) brown (10YR 5/3) gravelly clay loam, Bt horizon dark yellowish brown (10YR 3/4) moist; weak Hue: 5YR, 7.5YR, or 10YR medium subangular blocky structure; moderately Value: 5 to 7 dry; 4 or 5 moist hard, friable, slightly sticky, slightly plastic; few Chroma: 2 to 4 or 6 very fine roots; common very fine and fine pores; Texture (less than 2 mm): Clay loam or loam 15 percent gravel; neutral (pH 6.8); clear wavy Clay content: 20 to 35 percent boundary. Content of rock fragments: 5 to 35 percent—0 to Bt—36 to 60 inches; brown (10YR 5/3) gravelly clay 15 percent stones and cobbles; 5 to 20 percent loam, brown (10YR 4/3) moist; moderate medium gravel subangular blocky structure; moderately hard, Reaction: pH 6.1 to 7.3 friable, moderately sticky, moderately plastic; few very fine roots; few very fine pores; few faint discontinuous dark yellowish brown (10YR 3/4) Radersburg Series moist; clay films on faces of peds and lining Depth class: Very deep (greater than 60 inches) pores; 25 percent gravel; neutral (pH 6.8). Drainage class: Well drained Range in Characteristics Permeability: Moderately slow (0.2 to 0.6 inch/hour) Landform: Fan, stream terrace, terrace, and fan on Soil temperature: 43 to 46 degrees F escarpment Moisture control section: Between 4 and 12 inches Parent material: Gravelly alluvium Thickness of the mollic epipedon: 10 to 15 inches Slope range: 0 to 60 percent Depth to the top of the argillic horizon: 24 to Elevation range: 3,750 to 5,200 feet 40 inches Mean annual precipitation: 10 to 14 inches A horizons Mean annual air temperature: 43 to 46 degrees F Hue: 7.5YR or 10YR Frost-free period: 95 to 130 days Value: 3 or 4 dry; 2 or 3 moist Chroma: 1 or 2 Taxonomic Class: Clayey-skeletal, mixed, Texture (less than 2 mm): Loam superactive, frigid Aridic Argiustolls Clay content: 15 to 25 percent Typical Pedon Content of rock fragments: 0 to 20 percent—0 to 5 percent cobbles; 0 to 15 percent gravel Radersburg very cobbly loam, 300 feet west of the Reaction: pH 5.6 to 7.3 center of sec. 28, T. 8 N., R. 1 E.; Broadwater County, Montana. E horizon Hue: 5YR, 7.5YR, or 10YR A—0 to 4 inches; grayish brown (10YR 5/2) very Value: 5 to 7 dry; 4 or 5 moist cobbly loam, very dark grayish brown (10YR 3/2) Chroma: 1 to 3 moist; moderate thin platy structure parting to Texture (less than 2 mm): Loam or silt loam moderate very fine granular; slightly hard, very Clay content: 15 to 27 percent friable, slightly sticky, slightly plastic; 55 percent Sweet Grass County Area, Montana—Part I 115

cobbles and gravel; many very fine and fine roots Chroma: 2 to 4 and pores; slightly alkaline (pH 7.8); abrupt Texture (less than 2 mm): Silt loam or clay loam smooth boundary. Clay content: 20 to 35 percent Bt—4 to 15 inches; brown (10YR 5/3) very cobbly Content of rock fragments: 25 to 45 percent—5 to clay, dark brown (10YR 3/3) moist; moderate 10 percent stones; 10 to 20 percent cobbles; medium prismatic structure parting to strong fine 10 to 15 percent gravel angular blocky; hard, firm, moderately sticky, Calcium carbonate equivalent: 5 to 15 percent moderately plastic; 40 percent cobbles and Reaction: pH 7.9 to 9.0 gravel; common distinct clay films on faces of C horizon peds; many very fine and fine roots and pores; Hue: 10YR or 2.5Y slightly alkaline (pH 7.8); clear smooth boundary. Value: 5 to 8 dry; 4 to 6 moist Bk—15 to 30 inches; light gray (10YR 7/2) very Chroma: 2 to 4 cobbly silt loam, grayish brown (2.5Y 5/2) moist; Texture (less than 2 mm): Loam or clay loam massive; hard, friable, slightly sticky, slightly Clay content: 20 to 35 percent plastic; 45 percent cobbles and gravel; common Content of rock fragments: 25 to 45 percent—5 to distinct carbonate coats on undersides of rock 10 percent stones; 10 to 20 percent cobbles; fragments; strongly effervescent; moderately 10 to 15 percent gravel alkaline (pH 8.2); clear wavy boundary. Calcium carbonate equivalent: 5 to 15 percent C—30 to 60 inches; light yellowish brown (2.5Y 6/4) Reaction: pH 7.9 to 9.0 cobbly loam, olive brown (2.5Y 4/4) moist; massive; slightly hard, very friable, slightly sticky, slightly plastic; 55 percent cobbles and gravel; Redchief Series strongly effervescent; moderately alkaline (pH 8.2). Depth class: Very deep (greater than 60 inches) Drainage class: Well drained Range in Characteristics Permeability: Slow (0.06 to 0.20 inch/hour) Soil temperature: 40 to 47 degrees F Landform: Mountain, outwash plain, and terrace Moisture control section: Between 4 and 12 inches Parent material: Gravelly alluvium, gravelly Thickness of the mollic epipedon: 7 to 12 inches glaciofluvial deposits, or gravelly till Depth to the Bk horizon: 10 to 20 inches Slope range: 2 to 60 percent Elevation range: 5,500 to 7,500 feet A horizon Mean annual precipitation: 20 to 25 inches Hue: 10YR or 2.5Y Mean annual air temperature: 36 to 38 degrees F Value: 4 or 5 dry; 2 or 3 moist Frost-free period: 50 to 70 days Chroma: 2 or 3 Texture (less than 2 mm): Loam Taxonomic Class: Clayey-skeletal, smectitic Ustic Clay content: 15 to 27 percent Argicryolls Content of rock fragments: 0 to 60 percent—0 to 10 percent stones; 0 to 30 percent cobbles; Typical Pedon 0 to 20 percent gravel Redchief gravelly loam, in an area of Redchief Reaction: pH 6.6 to 7.8 gravelly loam, 4 to 15 percent slopes, in an area of Bt horizon rangeland, 300 feet south and 2,600 feet east of Hue: 10YR or 2.5Y the northwest corner of sec. 14, T. 2 N., R. 12 E.; Value: 4 or 5 dry; 3 moist USGS Raspberry Butte topographic quadrangle Chroma: 2 or 3 (lat. 45o55'44" N.; long. 110o11'58" W.) Texture (less than 2 mm): Clay or clay loam A—0 to 8 inches; brown (10YR 4/3) gravelly loam, Clay content: 35 to 55 percent very dark grayish brown (10YR 3/2) moist; strong Content of rock fragments: 35 to 65 percent—5 to fine granular structure; hard, friable, slightly 20 percent stones; 20 to 30 percent cobbles; sticky, slightly plastic; many very fine to medium 10 to 15 percent gravel roots; common fine pores; 20 percent gravel; Reaction: pH 7.4 to 8.4 5 cobbles; neutral (pH 6.8); clear wavy boundary. Bk horizon Bt1—8 to 14 inches; brown (7.5YR 4/2) very gravelly Hue: 10YR or 2.5Y clay loam, dark brown (7.5YR 3/3) moist; strong Value: 6 or 7 dry; 4 to 6 moist fine and medium subangular blocky structure; 116 Soil Survey

very hard, firm, very sticky, very plastic; common Texture (less than 2 mm): Clay loam or clay very fine and fine roots; common very fine and Clay content: 35 to 60 percent fine pores; common prominent continuous brown Content of rock fragments: 35 to 70 percent—5 to (7.5YR 4/4) moist; clay films on faces of peds and 20 percent stones and cobbles; 30 to lining pores; 25 percent gravel; 10 percent 50 percent gravel cobbles; neutral (pH 6.8); clear wavy boundary. Reaction: pH 5.1 to 7.3 Bt2—14 to 25 inches; brown (7.5YR 5/4) very gravelly Bt3 horizon clay loam, brown (7.5YR 4/4) moist; strong Hue: 2.5YR, 5YR, 7.5YR, or 10YR medium subangular blocky structure; very hard, Value: 4 to 6 dry; 4 or 5 moist firm, very sticky, very plastic; few very fine and Chroma: 2 to 4, 6, or 8 fine roots; few very fine and fine pores; many Texture (less than 2 mm): Clay loam or clay prominent continuous dark reddish brown (5YR Clay content: 35 to 60 percent 4/4) moist; clay films on faces of peds and lining Content of rock fragments: 35 to 70 percent—5 to pores; 30 percent gravel; 15 percent cobbles; 20 percent stones and cobbles; 30 to neutral (pH 6.8); clear wavy boundary. 60 percent gravel Bt3—25 to 60 inches; light yellowish brown (10YR 6/ Reaction: pH 5.1 to 7.3 4) very gravelly clay loam, brown (10YR 5/3) moist; weak medium and coarse subangular blocky structure; extremely hard, firm, very sticky, very plastic; common distinct patchy dark Redfern Series yellowish brown (10YR 4/4) moist; clay films on Depth class: Shallow (10 to 20 inches) faces of peds and rock fragments; 25 percent Drainage class: Well drained gravel; 15 percent cobbles; neutral (pH 6.8). Permeability: Moderate (0.6 to 2.0 inches/hour) Range in Characteristics Landform: Mountain Parent material: Loamy residuum weathered from Soil temperature: 36 to 45 degrees F sandstone and siltstone Moisture control section: Between 4 and 12 inches Slope range: 15 to 60 percent Thickness of the mollic epipedon: 10 to 16 inches Elevation range: 5,500 to 7,500 feet A horizon Mean annual precipitation: 20 to 25 inches Hue: 7.5YR or 10YR Mean annual air temperature: 36 to 38 degrees F Value: 2 to 4 dry; 2 or 3 moist Frost-free period: 50 to 70 days Chroma: 1 to 3 Texture (less than 2 mm): Loam Taxonomic Class: Loamy-skeletal, mixed, Clay content: 20 to 35 percent superactive Lithic Haplocryalfs Content of rock fragments: 15 to 40 percent—0 to 15 percent stones and cobbles; 15 to Typical Pedon 25 percent gravel Redfern very channery loam, in an area of Redfern- Reaction: pH 5.1 to 7.3 Fifer complex, 25 to 60 percent slopes, in an area of Bt1 horizon coniferous forest, 2,500 feet north and 1,500 feet Hue: 5YR, 7.5YR, or 10YR west of the southeast corner of sec. 12, T. 4 N., Value: 4 or 5 dry; 3 or 4 moist R. 12 E.; USGS Amelong Creek topographic Chroma: 2 to 4, 6 or 8 quadrangle (lat. 46o06'40" N.; long. 110o10'12" W.) Texture (less than 2 mm): Clay loam or clay Oi—0 to 2 inches; partially decomposed needles, Clay content: 35 to 60 percent twigs, and leaves. Content of rock fragments: 25 to 60 percent—0 to E—2 to 7 inches; very dark grayish brown (2.5Y 3/2) 20 percent stones and cobbles; 25 to very channery loam, grayish brown (2.5Y 5/2) 50 percent gravel dry; weak thin and medium platy structure and Reaction: pH 5.1 to 7.3 moderate very fine and fine subangular blocky; Bt2 horizon soft, friable, moderately sticky, moderately plastic; Hue: 5YR, 7.5YR, or 10YR common medium and coarse and many very fine Value: 4 to 6 dry; 4 or 5 moist and fine roots; common very fine and fine Chroma: 4, 6, or 8 interstitial and tubular pores; 35 percent angular Sweet Grass County Area, Montana—Part I 117

sandstone channers; neutral (pH 6.8); clear wavy Reedpoint Series boundary. E/Bt—7 to 11 inches; 60 percent, very dark grayish Depth class: Very shallow (0 to 10 inches) brown (2.5Y 3/2) very channery loam, grayish Drainage class: Well drained brown (2.5Y 5/2) dry (E); 40 percent, olive brown Permeability: Moderate (0.6 to 2.0 inches/hour) (2.5Y 4/3) very channery clay loam, light olive Landform: Escarpment, hill, knoll on plain, and brown (2.5Y 5/3) dry (Bt); weak fine and medium structural bench on plain subangular blocky structure; slightly hard, friable, Parent material: Residuum weathered from slightly sticky, slightly plastic; common fine and sandstone medium and many very fine roots; common Slope range: 2 to 60 percent very fine and fine interstitial and tubular pores; Elevation range: 3,750 to 5,200 feet 40 percent angular sandstone channers; neutral Mean annual precipitation: 10 to 14 inches (pH 6.8); clear wavy boundary. Mean annual air temperature: 43 to 46 degrees F Bt—11 to 20 inches; olive brown (2.5Y 4/3) very Frost-free period: 95 to 125 days channery clay loam, light olive brown (2.5Y 5/3) dry; moderate fine and medium subangular Taxonomic Class: Loamy-skeletal, mixed, blocky structure; slightly hard, friable, slightly superactive, frigid Lithic Haplustolls sticky, slightly plastic; common very fine and fine Typical Pedon roots; common very fine and fine interstitial and tubular pores; unspecified; 45 percent angular Reedpoint very channery loam, in an area of sandstone channers; neutral (pH 6.8); abrupt Ethridge-Reedpoint complex, 2 to 8 percent slopes, irregular boundary. in an area of rangeland, 900 feet south and 100 feet R—20 inches; bedrock; noneffervescent. east of the northwest corner of sec. 26, T. 4 N., R. 16 E.; USGS Gibson SW topographic quadrangle Range in Characteristics (lat. 46o04'17" N.; long. 109o42'26" W.) Soil temperature: 38 to 42 degrees F A—0 to 5 inches; grayish brown (10YR 5/3) very Moisture control section: Between 4 and 12 inches channery loam, dark brown (10YR 3/3) moist; Depth to the argillic horizon: 3 to 13 inches weak fine granular structure; soft, very friable, Depth to bedrock: 8 to 20 inches slightly sticky, slightly plastic; common very fine Surface stones or boulders: 0 to 20 percent and fine roots; many fine pores; 38 percent E horizon sandstone channers; neutral (pH 7.2); abrupt Hue: 10YR or 2.5Y smooth boundary. Value: 5 to 7 dry; 3, 5, or 6 moist R—5 inches; hard noncalcareous sandstone. Chroma: 2 or 3 Range in Characteristics Texture (less than 2 mm): Loam or sandy loam Clay content: 15 to 25 percent Soil temperature: 42 to 47 degrees F Content of rock fragments: 35 to 65 percent—0 to Moisture control section: Between 4 inches and 5 percent stones; 10 to 20 percent cobbles; 25 bedrock to 40 percent gravel or channers Thickness of the mollic epipedon: 4 to 9 inches Reaction: pH 6.1 to 7.3 Depth to bedrock: 4 to 10 inches Note: Some pedons have a Bw horizon. Bt horizon Hue: 10YR or 2.5Y A horizon Value: 5 or 6 dry; 4 or 5 moist Hue: 7.5YR or 10YR Chroma: 2 to 4 Value: 4 or 5 dry; 2 or 3 moist Texture (less than 2 mm): Clay loam or sandy Chroma: 2 or 3 clay loam Texture (less than 2 mm): Loam Clay content: 23 to 35 percent Clay content: 10 to 27 percent Content of rock fragments: 35 to 70 percent—0 to Content of rock fragments: 35 to 60 percent—0 to 15 percent stones; 15 to 30 percent cobbles; 15 percent flagstones; 35 to 45 percent 20 to 45 percent gravel or channers channers Reaction: pH 5.6 to 7.3 Reaction: pH 6.6 to 7.8 118 Soil Survey

Reedwest Series medium subangular blocky structure; slightly hard, very friable, slightly sticky, slightly plastic; Depth class: Moderately deep (20 to 40 inches) common very fine and fine pores; common Drainage class: Well drained medium soft masses of lime; strongly Permeability: Moderate (0.6 to 2.0 inches/hour) effervescent; moderately alkaline (pH 8.4); abrupt Landform: Escarpment, hill, terrace, and swale on smooth boundary. plain Cr—27 to 60 inches; calcareous soft sandstone. Parent material: Loamy residuum weathered from Range in Characteristics sandstone and siltstone Slope range: 0 to 60 percent Soil temperature: 41 to 47 degrees F Elevation range: 3,900 to 6,200 feet Moisture control section: Between 4 and 12 inches Mean annual precipitation: 15 to 20 inches Thickness of the mollic epipedon: 7 to 15 inches Mean annual air temperature: 39 to 45 degrees F Depth to the Bk horizon: 11 to 30 inches Frost-free period: 70 to 115 days Depth to bedrock: 20 to 40 inches A horizon Taxonomic Class: Fine-loamy, mixed, superactive, Hue: 10YR or 2.5Y frigid Typic Argiustolls Value: 3 to 5 dry; 2 or 3 moist Typical Pedon Chroma: 2 or 3 Texture (less than 2 mm): Loam Reedwest loam, in an area of Reedwest-Castner Clay content: 15 to 27 percent complex, 2 to 8 percent slopes, in an area of Content of rock fragments: 0 to 15 percent gravel rangeland, 200 feet south and 1,300 feet east of Reaction: pH 6.1 to 7.8 the northwest corner of sec. 33, T. 5 N., R. 15 E.; USGS Gougley Creek topographic quadrangle Bt horizons (lat. 46o08'48" N.; long. 109o51'25" W.) Hue: 10YR or 2.5Y Value: 4 to 6 dry; 3 to 5 moist A—0 to 6 inches; dark grayish brown (10YR 4/2) Chroma: 2 to 4 loam, very dark grayish brown (10YR 3/2) moist; Texture (less than 2 mm): Loam, sandy clay loam, moderate fine subangular blocky structure or clay loam parting to weak fine and medium granular; soft, Clay content: 18 to 35 percent very friable, slightly sticky, nonplastic; few Content of rock fragments: 0 to 15 percent gravel medium and common very fine and fine roots; Reaction: pH 6.6 to 7.8 many very fine and fine pores; slightly alkaline (pH 7.6); abrupt smooth boundary. Bk horizon Bt1—6 to 13 inches; dark grayish brown (10YR 4/2) Hue: 10YR, 2.5Y, or 5Y loam, very dark grayish brown (10YR 3/2) moist; Value: 6 to 8 dry; 4 to 6 moist moderate fine prismatic structure; slightly hard, Chroma: 2 to 4 friable, slightly sticky, slightly plastic; common Texture (less than 2 mm): Loam, sandy clay loam, very fine and fine roots; common very fine and fine sandy loam, or clay loam fine pores; common faint discontinuous dark Clay content: 15 to 30 percent brown (10YR 3/3) moist; clay films on faces of Content of rock fragments: 0 to 15 percent gravel peds and lining pores; slightly alkaline (pH 7.6); Calcium carbonate equivalent: 5 to 15 percent clear smooth boundary. Reaction: pH 7.4 to 8.4 Bt2—13 to 19 inches; brown (10YR 5/3) clay loam, dark brown (10YR 4/3) moist; moderate medium prismatic structure parting to strong medium Rentsac Series subangular blocky; slightly hard, friable, moderately sticky, moderately plastic; few very Depth class: Shallow (10 to 20 inches) fine and fine roots; common very fine and fine Drainage class: Well drained pores; common distinct discontinuous dark brown Permeability: Moderate (0.6 to 2.0 inches/hour) (10YR 3/3) moist; clay films on faces of peds and Landform: Escarpment, hill, and knoll on plain lining pores; slightly alkaline (pH 7.6); clear Parent material: Residuum weathered from smooth boundary. calcareous sandstone Bk—19 to 27 inches; light brownish gray (2.5Y 6/2) Slope range: 2 to 60 percent loam, grayish brown (2.5Y 4/2) moist; moderate Elevation range: 3,750 to 5,200 feet Sweet Grass County Area, Montana—Part I 119

Mean annual precipitation: 10 to 14 inches Content of rock fragments: 0 to 60 percent gravel Mean annual air temperature: 43 to 46 degrees F or channers Frost-free period: 95 to 125 days Calcium carbonate equivalent: 0 to 5 percent Reaction: pH 6.6 to 8.4 Taxonomic Class: Loamy-skeletal, mixed, Bk1 horizon superactive, frigid Lithic Calciustepts Hue: 7.5YR, 10YR, or 2.5Y Typical Pedon Value: 5 to 7 dry; 4 or 5 moist Chroma: 2 to 4 Rentsac channery loam, in an area of Yawdim- Texture (less than 2 mm): Loam, sandy loam, or Rentsac-Cabbart complex, 2 to 15 percent slopes, in fine sandy loam an area of pasture, 2,000 feet south and 400 feet Clay content: 7 to 18 percent west of the northeast corner of sec. 6, T. 3 N., Content of rock fragments: 0 to 80 percent—0 to R. 17 E.; USGS Gibson SW topographic quadrangle 30 percent flagstones or cobbles; 0 to (lat. 46o02'21" N.; long. 109o39'14" W.) 50 percent gravel or channers A—0 to 2 inches; grayish brown (10YR 5/2) channery Calcium carbonate equivalent: 5 to 15 percent loam, brown (10YR 4/3) moist; weak fine granular Reaction: pH 6.6 to 8.4 structure; soft, very friable, slightly sticky, Bk2 horizon nonplastic; many very fine and fine roots; many Hue: 7.5YR, 10YR, or 2.5Y very fine pores; 15 percent sandstone channers; Value: 5 to 7 dry; 4 to 6 moist slightly effervescent; slightly alkaline (pH 7.6); Chroma: 2 to 4 or 6 clear smooth boundary. Texture (less than 2 mm): Loam, sandy loam, or Bk1—2 to 5 inches; pale brown (10YR 6/3) channery fine sandy loam loam, grayish brown (10YR 5/2) moist; weak Clay content: 7 to 18 percent medium subangular blocky structure; soft, very Content of rock fragments: 35 to 70 percent—0 to friable, slightly sticky, nonplastic; common fine 35 percent flagstones or cobbles; 25 to roots; common very fine and fine pores; few fine 55 percent gravel or channers soft masses of lime; common carbonate coats on Calcium carbonate equivalent: 5 to 15 percent undersides of rock fragments; 20 percent Electrical conductivity: 0 to 4 mmhos/cm sandstone channers; slightly effervescent; slightly Reaction: pH 7.4 to 8.4 alkaline (pH 7.6); abrupt smooth boundary. Bk2—5 to 16 inches; light gray (10YR 7/2) very channery fine sandy loam, light brownish gray Richey Series (10YR 6/2) moist; weak medium subangular blocky structure; soft, very friable, nonsticky, Depth class: Very deep (greater than 60 inches) nonplastic; few fine and medium roots; common Drainage class: Well drained fine soft masses of lime; common carbonate Permeability: Slow (0.06 to 0.20 inch/hour) coats on undersides of rock fragments; 5 percent Landform: Fan, hill, stream terrace, terrace, and flagstones; 5 percent cobbles; 45 percent swale on plain channers; strongly effervescent; moderately Parent material: Clayey alluvium alkaline (pH 8.2); abrupt wavy boundary. Slope range: 0 to 8 percent R—16 inches; hard calcareous sandstone. Elevation range: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Range in Characteristics Mean annual air temperature: 43 to 46 degrees F Frost-free period: 95 to 125 days Soil temperature: 42 to 47 degrees F Moisture control section: Between 8 inches and the Taxonomic Class: Fine, smectitic, frigid Torrertic lithic contact Haplustolls Depth to bedrock: 10 to 20 inches Typical Pedon A horizon Hue: 7.5YR, 10YR, or 2.5Y Richey silty clay, 0 to 4 percent slopes, in an area of Value: 5 or 6 dry; 3 or 4 moist rangeland, 1,300 feet south and 500 feet west of the Chroma: 2 or 3 northeast corner of sec. 22, T. 5 N., R. 16 E.; USGS Texture (less than 2 mm): Loam or sandy loam Jim Creek topographic quadrangle (lat. 46o10'20" N.; Clay content: 7 to 18 percent long. 109o41'48" W.) 120 Soil Survey

A—0 to 7 inches; grayish brown (10YR 5/2) silty clay, Calcium carbonate equivalent: 5 to 10 percent dark brown (10YR 3/3) moist; moderate medium Reaction: pH 7.9 to 9.0 granular structure; slightly hard, friable, Bk horizon moderately sticky, moderately plastic; many very Hue: 10YR or 2.5Y fine and fine roots; many very fine and fine pores; Value: 5 or 6 dry; 4 or 5 moist slightly alkaline (pH 7.4); abrupt smooth Chroma: 2 or 3 boundary. Texture (less than 2 mm): Silty clay or silty clay Bw—7 to 13 inches; light brownish gray (10YR 6/2) loam silty clay, dark grayish brown (10YR 4/2) moist; Clay content: 35 to 45 percent moderate coarse angular blocky structure parting Content of rock fragments: 0 to 5 percent gravel to strong fine and medium angular blocky; very Calcium carbonate equivalent: 5 to 15 percent hard, firm, very sticky, very plastic; many fine Reaction: pH 7.9 to 9.0 roots; common very fine and fine pores; strongly effervescent; moderately alkaline (pH 8.2); clear Bky horizon smooth boundary. Hue: 10YR or 2.5Y Bk—13 to 23 inches; light brownish gray (2.5Y 6/2) Value: 5 to 7 dry; 4 or 5 moist silty clay, grayish brown (2.5Y 5/2) moist; Chroma: 2 or 3 moderate coarse prismatic structure; very hard, Texture (less than 2 mm): Silty clay, clay loam, or firm, very sticky, very plastic; common fine roots; silty clay loam common very fine and fine pores; few fine and Clay content: 35 to 45 percent medium carbonate threads; strongly effervescent; Content of rock fragments: 0 to 5 percent gravel strongly alkaline (pH 8.6); clear smooth boundary. Calcium carbonate equivalent: 5 to 10 percent Bky—23 to 60 inches; light gray (2.5Y 7/2) silty clay, Electrical conductivity: 0 to 4 mmhos/cm light olive brown (2.5Y 5/3) moist; moderate Gypsum content: 1 to 5 percent coarse prismatic structure; very hard, firm, very Reaction: pH 7.9 to 9.0 sticky, very plastic; few fine and medium roots; common very fine pores; few fine gypsum crystals; many fine and medium carbonate Rocko Series threads; strongly effervescent; strongly alkaline Depth class: Very deep (greater than 60 inches) (pH 8.6). Drainage class: Well drained Permeability: Moderate (0.6 to 2.0 inches/hour) Range in Characteristics Landform: Mountain Parent material: Gravelly colluvium Soil temperature: 41 to 46 degrees F Slope range: 15 to 45 percent Moisture control section: Between 4 and 12 inches Elevation range: 5,500 to 7,500 feet Thickness of the mollic epipedon: 7 to 12 inches Mean annual precipitation: 20 to 25 inches Depth to the Bk horizon: 12 to 20 inches Mean annual air temperature: 36 to 38 degrees F A horizon Frost-free period: 50 to 70 days Hue: 10YR or 2.5Y Value: 5 dry; 2 or 3 moist Taxonomic Class: Loamy-skeletal, mixed, Chroma: 2 or 3 superactive Ustollic Haplocryalfs Texture (less than 2 mm): Silty clay or clay loam Typical Pedon Clay content: 30 to 55 percent Content of rock fragments: 0 to 5 percent gravel Rocko cobbly loam, in an area of Rocko-Adel Reaction: pH 6.6 to 7.8 complex, 15 to 45 percent slopes, in an area of coniferous forest, 500 feet south and 800 feet west Bw horizon of the northeast corner of sec. 2, T. 2 N., R. 12 E.; Hue: 10YR or 2.5Y USGS Raspberry Butte quadrangle (lat. 45o57'26" N.; Value: 5 or 6 dry; 3 to 5 moist long. 110o11'31" W.) Chroma: 2 or 3 Texture (less than 2 mm): Silty clay or silty clay Oi—0 to 2 inches; slightly decomposed needles and loam twigs. Clay content: 35 to 45 percent A—2 to 7 inches; dark gray (2.5Y 4/1) cobbly loam, Content of rock fragments: 0 to 5 percent gravel black (2.5Y 2/1) moist; strong very fine and fine Sweet Grass County Area, Montana—Part I 121

granular structure; soft, very friable, nonsticky, A horizon nonplastic; common medium and coarse and Hue: 10YR or 2.5Y many very fine and fine roots; many very fine and Value: 3 to 5 dry; 2 or 3 moist fine pores; 13 percent gravel; 7 percent cobbles; Chroma: 1 to 3 3 percent stones; moderately acid (pH 6.0); clear Texture (less than 2 mm): Loam smooth boundary. Clay content: 18 to 27 percent E—7 to 11 inches; grayish brown (2.5Y 5/2) cobbly Content of rock fragments: 15 to 35 percent— loam, dark grayish brown (2.5Y 4/2) moist; 10 to 20 percent stones and cobbles; 5 to moderate very fine and fine granular structure; 15 percent gravel slightly hard, friable, slightly sticky, slightly plastic; Reaction: pH 5.6 to 7.3 common medium and coarse and many very fine E horizon and fine roots; many very fine and fine pores; Hue: 10YR or 2.5Y 13 percent gravel; 13 percent cobbles; Value: 5 or 6 dry; 4 or 5 moist moderately acid (pH 6.0); gradual smooth Chroma: 1 or 2 boundary. Texture (less than 2 mm): Loam Bt1—11 to 26 inches; light yellowish brown (2.5Y 6/3) Clay content: 18 to 27 percent very cobbly sandy clay loam, olive brown (2.5Y Content of rock fragments: 15 to 40 percent— 4/3) moist; moderate fine and medium 10 to 20 percent stones and cobbles; 5 to subangular blocky structure; moderately hard, 20 percent gravel friable, slightly sticky, slightly plastic; few very fine Reaction: pH 5.6 to 7.3 to coarse roots; few distinct discontinuous dark yellowish brown (10YR 3/4) moist; clay films on Bt horizons rock fragments; 17 percent gravel; 13 percent Hue: 10YR or 2.5Y cobbles; 7 percent stones; slightly acid (pH 6.2); Value: 4 to 6 dry; 3 to 5 moist gradual smooth boundary. Chroma: 2 to 4 Bt2—26 to 35 inches; light yellowish brown (2.5Y 6/3) Texture (less than 2 mm): Sandy clay loam, clay very cobbly clay loam, olive brown (2.5Y 4/3) loam, or loam moist; moderate fine and medium subangular Clay content: 25 to 35 percent blocky structure; moderately hard, friable, slightly Content of rock fragments: 35 to 60 percent— sticky, slightly plastic; few very fine to coarse 20 to 30 percent stones and cobbles; 15 to roots; common distinct discontinuous dark 30 percent gravel yellowish brown (10YR 3/4) moist; clay films on Reaction: pH 6.1 to 7.8 faces of peds and rock fragments; 23 percent BC horizon gravel; 17 percent cobbles; 7 percent stones; Hue: 10YR or 2.5Y slightly acid (pH 6.4); gradual wavy boundary. Value: 5 or 6 dry; 4 or 5 moist Bt3—35 to 41 inches; light yellowish brown (2.5Y 6/4) Chroma: 3 or 4 very cobbly sandy clay loam, olive brown (2.5Y Texture (less than 2 mm): Sandy clay loam, 4/3) moist; moderate fine and medium sandy loam, or loam subangular blocky structure; moderately hard, Clay content: 18 to 27 percent friable, slightly sticky, slightly plastic; few medium Content of rock fragments: 35 to 70 percent— and coarse roots; few distinct discontinuous dark 20 to 35 percent stones and cobbles; 15 to yellowish brown (10YR 3/4) moist; clay films on 35 percent gravel rock fragments; 23 percent gravel; 20 percent Reaction: pH 6.6 to 7.8 cobbles; 4 percent stones; neutral (pH 6.6); gradual wavy boundary. BC—41 to 62 inches; light yellowish brown (2.5Y 6/4) Roy Series very gravelly sandy clay loam, light olive brown (2.5Y 5/3) moist; massive; slightly hard, friable, Depth class: Very deep (greater than 60 inches) slightly sticky, slightly plastic; few medium roots; Drainage class: Well drained 33 percent gravel; 10 percent cobbles; 13 percent Permeability: Moderately slow (0.2 to 0.6 inch/hour) stones; neutral (pH 6.6). Landform: Escarpment, fan, landslide, stream terrace, terrace Range in Characteristics Parent material: Gravelly alluvium or gravelly Soil temperature: 36 to 40 degrees F glaciofluvial deposits Moisture control section: Between 4 and 12 inches Slope range: 0 to 60 percent 122 Soil Survey

Elevation range: 4,200 to 6,200 feet Thickness of the mollic epipedon: 10 to 16 inches Mean annual precipitation: 15 to 20 inches Depth to the Bk horizon: 20 to 40 inches Mean annual air temperature: 39 to 45 degrees F A horizon Frost-free period: 70 to 115 days Hue: 7.5YR or 10YR Value: 4 or 5 dry; 2 or 3 moist Taxonomic Class: Clayey-skeletal, mixed, Chroma: 2 or 3 superactive, frigid Typic Argiustolls Texture (less than 2 mm): Loam or clay loam Typical Pedon Clay content: 12 to 40 percent Content of rock fragments: 5 to 55 percent—5 to Roy very gravelly loam, in an area of Roy-Tamaneen 20 percent stones and cobbles; 0 to complex, 2 to 8 percent slopes, in an area of 35 percent gravel rangeland, 800 feet north and 1,500 feet west of Reaction: pH 6.1 to 7.8 the southeast corner of sec. 20, T. 5 N., R. 13 E. USGS Porcupine Butte topographic quadrangle Bt1 horizon (lat. 46o09'52" N.; long. 110o07'07" W.) Hue: 7.5YR or 10YR Value: 4 or 5 dry; 3 or 4 moist A—0 to 4 inches; brown (10YR 4/3) very gravelly Chroma: 2 to 4 loam, dark brown (10YR 3/2) moist; moderate Texture (less than 2 mm): Clay loam or clay fine granular structure; slightly hard, very friable, Clay content: 35 to 50 percent slightly sticky, nonplastic; few fine and many very Content of rock fragments: 35 to 80 percent— fine roots; few fine and common very fine pores; 15 to 40 percent stones and cobbles; 20 to 13 percent cobbles; 31 percent gravel; neutral 40 percent gravel (pH 7.2); clear smooth boundary. Reaction: pH 6.6 to 7.8 Bt1—4 to 10 inches; brown (10YR 5/3) very cobbly clay loam, dark brown (10YR 3/3) moist; Bt2 horizon moderate medium prismatic structure parting to Hue: 7.5YR or 10YR moderate fine subangular blocky; moderately Value: 4 or 5 dry; 3 or 4 moist hard, friable, moderately sticky, moderately Chroma: 2 to 4 or 6 plastic; few fine and common very fine roots; few Texture (less than 2 mm): Clay loam or clay fine and common very fine pores; common Clay content: 35 to 50 percent distinct dark brown (10YR 4/3) moist; clay films Content of rock fragments: 35 to 80 percent— on faces of peds; 17 percent cobbles; 22 percent 15 to 40 percent stones and cobbles; 20 to gravel; neutral (pH 7.2); clear smooth boundary. 40 percent gravel Bt2—10 to 21 inches; brown (10YR 5/3) very cobbly Reaction: pH 6.6 to 7.8 clay loam, dark brown (10YR 3/3) moist; weak Bk horizon fine subangular blocky structure; moderately Hue: 7.5YR, 10YR, or 2.5Y hard, friable, moderately sticky, moderately Value: 5 or 6 dry; 4 or 5 moist plastic; few very fine and fine roots; few very fine Chroma: 2 to 4 or 6 pores; few faint dark brown (10YR 4/3) moist; Texture (less than 2 mm): Clay loam or sandy clay films on faces of peds; 21 percent cobbles; clay loam 32 percent gravel; neutral (pH 7.2); clear wavy Clay content: 27 to 40 percent boundary. Content of rock fragments: 35 to 80 percent— Bk—21 to 60 inches; light brownish gray (10YR 6/2) 20 to 50 percent stones and cobbles; 15 to very cobbly clay loam, dark grayish brown (10YR 30 percent gravel 4/2) moist; weak medium subangular blocky Calcium carbonate equivalent: 2 to 15 percent structure; moderately hard, friable, slightly sticky, Electrical conductivity: 0 to 4 mmhos/cm slightly plastic; few very fine roots; few very fine Reaction: pH 7.4 to 8.4 pores; common carbonate coats on undersides of rock fragments; 25 percent cobbles; 15 percent gravel; strongly effervescent; moderately alkaline Roy Taxadjunct (pH 8.2). Depth class: Very deep (greater than 60 inches) Range in Characteristics Drainage class: Well drained Soil temperature: 40 to 47 degrees F Permeability: Slow (0.06 to 0.20 inch/hour) Moisture control section: Between 4 and 12 inches Landform: Landslide in foothills and mountains Sweet Grass County Area, Montana—Part I 123

Parent material: Clayey colluvium weathered from Bt2—22 to 32 inches; grayish brown (2.5Y 5/2) sandstone and shale extremely gravelly clay loam, brown (2.5Y 4/3) Slope range: 8 to 35 percent moist; weak fine granular structure; moderately Elevation range: 5,300 to 6,200 feet hard, friable, moderately sticky, moderately Mean annual precipitation: 17 to 20 inches plastic; few medium and common fine roots; Mean annual air temperature: 39 to 43 degrees F common distinct dark yellowish brown (10YR 4/4) Frost-free period: 70 to 90 days moist; clay films on faces of peds; many fine to coarse pores; 55 percent gravel; 10 percent Taxonomic Class: Clayey-skeletal, smectitic, frigid cobbles; 5 percent stones; moderately acid Typic Argiustolls (pH 5.8); clear smooth boundary. C—32 to 60 inches; light brownish gray (2.5Y 6/2) The Roy soils as mapped in map unit 429E are very gravelly clay loam, olive brown (2.5Y 4/3) taxadjunct to the series. They are outside the series moist; massive; moderately hard, friable, range with a smectitic mineralogy class in the 10- to moderately sticky, moderately plastic; few fine 40-inch particle size control section. Use and and medium roots; many fine to coarse pores; management are not significantly affected. Roy series 25 percent channers; 10 percent cobbles; classifies Clayey-skeletal, mixed, superactive, frigid 5 percent stones; moderately acid (pH 5.6). Typic Argiustolls. Range in Characteristics Typical Pedon Roy very stony clay loam, in an area of Work-Roy, Soil temperature: 41 to 45 degrees F bouldery-Bigsag family complex, 2 to 35 percent Moisture control section: Between 4 and 12 inches slopes, in an area of rangeland, 700 feet north and A1 horizon 1,500 feet east of the southwest corner of sec. 14, Hue: 10YR, 2.5Y, or 5Y T. 3 S., R. 12 E.; USGS McLeod Basin topographic Value: 3 to 5 dry; 2 or 3 moist quadrangle (lat. 45o33'11" N.; long. 110o12'40" W.) Chroma: 2 or 3 A1—0 to 4 inches; grayish brown (2.5Y 5/2) very Texture (less than 2 mm): Clay loam stony clay loam, very dark grayish brown (2.5Y Clay content: 30 to 40 percent 3/2) moist; weak fine granular structure; slightly Content of rock fragments: 15 to 60 percent—0 to hard, friable, moderately sticky, moderately 5 percent boulders; 5 to 30 percent stones and plastic; many very fine and fine roots; many very cobbles; 10 to 25 percent gravel fine and fine pores; 10 percent gravel; 10 percent Reaction: pH 6.1 to 7.3 cobbles; 20 percent stones; 1 percent boulders; A2 horizon neutral (pH 6.8); clear smooth boundary. Hue: 10YR or 2.5Y A2—4 to 12 inches; grayish brown (2.5Y 5/2) very Value: 5 or 6 dry; 3 or 4 moist gravelly clay, very dark grayish brown (2.5Y 3/2) Chroma: 2 or 3 moist; weak fine and medium subangular blocky Texture (less than 2 mm): Clay loam structure; moderately hard, friable, moderately Clay content: 30 to 40 percent sticky, moderately plastic; common very fine and Content of rock fragments: 15 to 60 percent—0 to fine roots; many fine to coarse pores; 30 percent 5 percent boulders; 5 to 30 percent stones and gravel; 5 percent cobbles; 5 percent stones; cobbles; 10 to 25 percent gravel slightly effervescent; neutral (pH 6.8); clear Reaction: pH 6.1 to 7.3 smooth boundary. Bt1—12 to 22 inches; grayish brown (2.5Y 5/2) very Bt horizons gravelly clay loam, dark grayish brown (2.5Y 4/2) Hue: 10YR or 2.5Y moist; weak coarse prismatic structure parting to Value: 4 or 5 dry; 3 or 4 moist weak fine granular; moderately hard, friable, Chroma: 2 to 4 moderately sticky, moderately plastic; common Texture (less than 2 mm): Clay loam or clay fine roots; common distinct dark brown (10YR 4/ Clay content: 35 to 55 percent 3) moist; clay films on faces of peds; many fine to Content of rock fragments: 35 to 80 percent— coarse pores; 30 percent gravel; 5 percent 15 to 40 percent stones and cobbles; 20 to cobbles; 5 percent stones; slightly acid (pH 6.4); 40 percent gravel clear smooth boundary. Reaction: pH 6.6 to 7.3 124 Soil Survey

C horizon Bw2—8 to 15 inches; grayish brown (2.5Y 5/2) clay Hue: 10YR or 2.5Y loam, dark grayish brown (2.5Y 4/2) moist; Value: 4 to 6 dry; 3 or 4 moist moderate medium prismatic structure; slightly Chroma: 2 or 3 hard, friable, moderately sticky, moderately Texture (less than 2 mm): Clay loam or clay plastic; few medium and common very fine and Clay content: 35 to 55 percent fine roots; common very fine and fine pores; Content of rock fragments: 35 to 80 percent—0 to strongly effervescent; moderately alkaline 5 percent boulders; 10 to 30 percent stones (pH 8.4); clear wavy boundary. and cobbles; 25 to 45 percent gravel Bk1—15 to 36 inches; light brownish gray (2.5Y 6/2) Reaction: pH 6.6 to 7.3 clay loam, grayish brown (2.5Y 5/2) moist; moderate coarse subangular blocky structure; moderately hard, firm, very sticky, moderately Sagedale Series plastic; common very fine and fine roots; common very fine and fine pores; few fine and medium soft Depth class: Very deep (60 inches or more) masses and fine threads of lime; 5 percent gravel; Drainage class: Well drained strongly effervescent; strongly alkaline (pH 8.4); Permeability: Moderate (0.6 to 2.0 inches/hour) gradual smooth boundary. Landform: Fan, hill, stream terrace, terrace, fan on Bk2—36 to 60 inches; light brownish gray (2.5Y 6/2) escarpment, swale on escarpment, and swale on clay loam, grayish brown (2.5Y 5/2) moist; weak plain coarse subangular blocky structure; moderately Parent material: Clayey alluvium weathered from hard, firm, very sticky, moderately plastic; few shale and siltstone very fine and fine roots; common fine soft masses Slope range: 0 to 35 percent and threads of lime; 5 percent gravel; strongly Elevation range: 3,900 to 6,000 feet effervescent; strongly alkaline (pH 8.4). Mean annual precipitation: 15 to 19 inches Range in Characteristics Mean annual air temperature: 43 to 45 degrees F Frost-free period: 85 to 115 days Soil temperature: 42 to 47 degrees F Moisture control section: Between 4 and 12 inches Taxonomic Class: Fine, smectitic, frigid Typic Depth to the Bk horizon: 10 to 18 inches Haplustepts A horizon Typical Pedon Hue: 10YR or 2.5Y Value: 5 or 6 dry; 4 or 5 moist Sagedale clay loam, in an area of Sagedale clay Chroma: 2 or 3 loam, 8 to 15 percent slopes, in an area of hayland, Texture (less than 2 mm): Clay loam 2,000 south and 2,430 west of the northeast corner Clay content: 30 to 40 percent of sec. 29, T. 4 N., R. 14 E.; USGS Battleship Butte Content of rock fragments: 0 to 5 percent gravel topographic quadrangle (lat. 46o04'11" N.; long. Reaction: pH 7.4 to 8.4 110o00'23" W.) Bw horizons Ap—0 to 4 inches; grayish brown (2.5Y 5/2) clay Hue: 10YR or 2.5Y loam, dark grayish brown (2.5Y 4/2) moist; Value: 5 or 6 dry; 4 or 5 moist moderate thick platy structure; slightly hard, firm, Chroma: 2 to 4 moderately sticky, moderately plastic; common Texture (less than 2 mm): Clay loam, silty clay very fine and fine roots; common very fine and loam, or silty clay fine pores; slightly effervescent; moderately Clay content: 35 to 45 percent alkaline (pH 8.4); clear smooth boundary. Content of rock fragments: 0 to 5 percent gravel Bw1—4 to 8 inches; grayish brown (2.5Y 5/2) clay Reaction: pH 7.4 to 8.4 loam, dark grayish brown (2.5Y 4/2) moist; weak medium prismatic structure parting to moderate Bk horizons coarse angular blocky; slightly hard, friable, Hue: 10YR or 2.5Y moderately sticky, moderately plastic; few Value: 5 to 7 dry; 4 to 6 moist medium and common very fine and fine roots; Chroma: 2 to 4 common very fine and fine pores; slightly Texture (less than 2 mm): Clay loam, silty clay effervescent; moderately alkaline (pH 8.4); clear loam, or silty clay smooth boundary. Clay content: 35 to 45 percent Sweet Grass County Area, Montana—Part I 125

Content of rock fragments: 0 to 5 percent gravel pores; faint patchy dark yellowish brown (10YR Calcium carbonate equivalent: 5 to 15 percent 3/4) moist; clay films on faces of peds; 27 percent Electrical conductivity: 0 to 4 mmhos/cm gravel; 23 percent cobbles; 7 percent stones; Reaction: pH 7.4 to 8.4 neutral (pH 6.8); clear smooth boundary. C—29 to 60 inches; light olive brown (2.5Y 5/4) extremely cobbly loam, olive brown (2.5Y 4/4) Sawicki Series moist; massive; soft, very friable, nonsticky, nonplastic; few very fine and fine roots; Depth class: Very deep (greater than 60 inches) 30 percent gravel; 30 percent subrounded Drainage class: Well drained cobbles; 7 percent stones; neutral (pH 6.8). Permeability: Moderate (0.6 to 2.0 inches/hour) Landform: Hill Range in Characteristics Parent material: Gravelly alluvium, gravelly colluvium Soil temperature: 40 to 45 degrees F or gravelly till Moisture control section: Between 4 and 12 inches Slope range: 4 to 25 percent Thickness of the mollic epipedon: 7 to 16 inches Elevation range: 5,300 to 6,200 feet Note: Some pedons have a BC horizon. Mean annual precipitation: 17 to 20 inches Mean annual air temperature: 39 to 43 degrees F A horizon Frost-free period: 70 to 90 days Hue: 10YR or 2.5Y Value: 3 or 4 dry; 2 or 3 moist Taxonomic Class: Loamy-skeletal, mixed, Chroma: 2 or 3 superactive, frigid Typic Argiustolls Texture (less than 2 mm): Loam Clay content: 12 to 27 percent Typical Pedon Content of rock fragments: 10 to 50 percent—0 to Sawicki very gravelly loam, in an area of Sawicki, 5 percent boulders; 5 to 20 percent stones and extremely bouldery-Bowery complex, 4 to 25 percent cobbles; 5 to 30 percent gravel slopes, in an area of rangeland, 900 feet south and Reaction: pH 6.6 to 7.3 1,000 feet east of the northwest corner of sec. 35, Bt1 horizon T. 2 S., R. 12 E.; USGS McLeod Basin topographic Hue: 10YR or 2.5Y quadrangle (lat. 45o37'21" N.; long. 110o12'48" W.) Value: 4 or 5 dry; 3 or 4 moist A—0 to 8 inches; very dark grayish brown (10YR 3/2) Chroma: 2 to 4 very gravelly loam, very dark brown (10YR 2/2) Texture (less than 2 mm): Clay loam, sandy clay moist; moderate very fine and fine granular loam, or loam structure; soft, very friable, nonsticky, nonplastic; Clay content: 20 to 30 percent few medium and many very fine and fine roots; Content of rock fragments: 15 to 60 percent— many very fine and fine pores; 25 percent gravel; 10 to 35 percent stones and cobbles; 5 to 10 percent cobbles; 5 percent stones; slightly 40 percent gravel acid (pH 6.4); clear smooth boundary. Reaction: pH 6.6 to 7.8 Bt1—8 to 15 inches; brown (10YR 4/3) very cobbly Bt2 horizon clay loam, very dark grayish brown (10YR 3/2) Hue: 10YR or 2.5Y moist; moderate fine and medium subangular Value: 4 to 6 dry; 3 to 5 moist blocky structure; slightly hard, firm, slightly sticky, Chroma: 2 to 4 slightly plastic; few medium and common very Texture (less than 2 mm): Sandy clay loam, fine and fine roots; common very fine and fine sandy loam, or loam pores; common distinct discontinuous dark Clay content: 15 to 25 percent yellowish brown (10YR 3/4) moist; clay films on Content of rock fragments: 35 to 60 percent— faces of peds; 20 percent gravel; 17 percent 15 to 45 percent stones and cobbles; 20 to cobbles; 3 percent stones; neutral (pH 6.8); clear 40 percent gravel smooth boundary. Reaction: pH 6.6 to 7.8 Bt2—15 to 29 inches; brown (10YR 5/3) very cobbly sandy clay loam, brown (10YR 4/3) moist; weak C horizon fine and medium subangular blocky structure; Hue: 10YR or 2.5Y slightly hard, friable, slightly sticky, slightly plastic; Value: 4 to 7 dry; 3 to 6 moist few very fine to medium roots; few very fine Chroma: 2 to 4 126 Soil Survey

Texture (less than 2 mm): Loam, sandy loam, 5 percent gravel; strongly effervescent; sandy clay loam, or loamy coarse sand moderately alkaline (pH 8.4); gradual wavy Clay content: 10 to 22 percent boundary. Content of rock fragments: 35 to 70 percent— Bk1—17 to 29 inches; light brownish gray (2.5Y 6/2) 15 to 55 percent stones and cobbles; 20 to clay loam, grayish brown (2.5Y 5/2) moist; 40 percent gravel moderate coarse subangular blocky structure; Reaction: pH 6.6 to 7.8 slightly hard, friable, slightly sticky, slightly plastic; few fine and medium roots; common very fine pores; 5 percent gravel; few fine soft masses and Shambo Series threads of lime; strongly effervescent; moderately alkaline (pH 8.4); clear wavy boundary. Depth class: Very deep (greater than 60 inches) Bk2—29 to 38 inches; light olive gray (5Y 6/2) clay Drainage class: Well drained loam, olive gray (5Y 5/2) moist; moderate coarse Permeability: Moderate (0.6 to 2.0 inches/hour) subangular blocky structure; slightly hard, friable, Landform: Fan, hill, landslide, moraine, stream slightly sticky, slightly plastic; few fine and terrace, terrace, fan on escarpment, swale on medium roots; few very fine pores; 5 percent escarpment, swale on plain gravel; common fine soft masses and threads of Parent material: Loamy alluvium lime; strongly effervescent; moderately alkaline Slope range: 0 to 35 percent (pH 8.4); clear wavy boundary. Elevation range: 4,200 to 6,200 feet BCk—38 to 60 inches; light olive gray (5Y 6/2) clay Mean annual precipitation: 15 to 20 inches loam, olive gray (5Y 4/2) moist; weak coarse Mean annual air temperature: 39 to 45 degrees F subangular blocky structure; moderately hard, Frost-free period: 70 to 115 days firm, moderately sticky, moderately plastic; few fine roots; few very fine pores; 8 percent gravel; Taxonomic Class: Fine-loamy, mixed, superactive, few fine threads of lime; strongly effervescent; frigid Typic Haplustolls moderately alkaline (pH 8.4). Typical Pedon Range in Characteristics Shambo loam, in an area of Shambo loam, 8 to Soil temperature: 42 to 47 degrees F 15 percent slopes, in an area of hayland, 500 feet Moisture control section: Between 4 and 12 inches south and 1,900 feet east of the northwest corner of Thickness of the mollic epipedon: 7 to 15 inches sec. 21, T. 3 N., R. 13 E.; USGS Battleship Butte Depth to the Bk horizon: 10 to 20 inches topographic quadrangle (lat. 46o00'06" N.; long. A horizon 110o06'56" W.) Hue: 10YR or 2.5Y Ap—0 to 5 inches; dark grayish brown (2.5Y 4/2) Value: 3 to 5 dry; 2 or 3 moist loam, very dark grayish brown (2.5Y 3/2) moist; Chroma: 2 or 3 moderate medium granular structure; soft, very Texture (less than 2 mm): Loam or clay loam friable, slightly sticky, slightly plastic; many fine Clay content: 10 to 35 percent roots; many very fine pores; neutral (pH 7.2); Content of rock fragments: 0 to 35 percent gravel clear smooth boundary. Reaction: pH 6.6 to 7.8 Bw1—5 to 10 inches; grayish brown (2.5Y 5/2) loam, Bw horizons very dark grayish brown (2.5Y 3/2) moist; weak Hue: 10YR or 2.5Y medium prismatic structure parting to moderate Value: 4 to 6 dry; 3 or 4 moist coarse subangular blocky; slightly hard, friable, Chroma: 2 to 4 slightly sticky, slightly plastic; many fine roots; Texture (less than 2 mm): Loam, silt loam, or clay many very fine pores; slightly effervescent; loam moderately alkaline (pH 8.0); clear smooth Clay content: 18 to 35 percent boundary. Content of rock fragments: 0 to 5 percent gravel Bw2—10 to 17 inches; grayish brown (2.5Y 5/2) clay Reaction: pH 6.6 to 8.4 loam, dark grayish brown (2.5Y 4/2) moist; weak medium prismatic structure parting to moderate Bk horizons coarse subangular blocky; slightly hard, friable, Hue: 10YR, 2.5Y, or 5Y slightly sticky, slightly plastic; few fine and Value: 5 to 7 dry; 4 to 6 moist common medium roots; common very fine pores; Chroma: 2 to 4 Sweet Grass County Area, Montana—Part I 127

Texture (less than 2 mm): Clay loam, silt loam, Bt—3 to 11 inches; very dark grayish brown (10YR silty clay loam, or loam 3/2) very gravelly clay loam, very dark brown Clay content: 18 to 35 percent (10YR 2/2) moist; weak medium subangular Content of rock fragments: 0 to 15 percent gravel blocky structure parting to moderate fine Calcium carbonate equivalent: 10 to 15 percent subangular blocky; moderately hard, friable, Sodium adsorption ratio: 1 to 5 moderately sticky, moderately plastic; common Reaction: pH 7.4 to 8.4 very fine roots; common very fine and fine pores; many distinct discontinuous very dark brown BCk horizon (10YR 2/2) moist; clay films on faces of peds; Hue: 10YR, 2.5Y, or 5Y 35 percent gravel; neutral (pH 7.2); clear smooth Value: 5 to 7 dry; 4 to 6 moist boundary. Chroma: 2 to 4 Btk—11 to 15 inches; grayish brown (10YR 5/2) very Texture (less than 2 mm): Clay loam, silt loam, gravelly clay loam, dark grayish brown (10YR 4/2) fine sandy loam, or loam moist; weak medium prismatic structure parting Clay content: 15 to 35 percent to weak very fine and fine subangular blocky; Content of rock fragments: 0 to 15 percent gravel moderately hard, friable, moderately sticky, Calcium carbonate equivalent: 5 to 10 percent moderately plastic; common very fine roots; Sodium adsorption ratio: 1 to 5 common very fine and fine pores; common faint Reaction: pH 7.4 to 8.4 dark brown (10YR 3/3) moist; clay films on faces of peds; common threads and soft masses of lime; 35 percent gravel; 5 percent cobbles; Shawmut Series strongly effervescent; slightly alkaline (pH 7.6); clear smooth boundary. Depth class: Very deep (greater than 60 inches) Bk1—15 to 25 inches; light brownish gray (10YR 6/2) Drainage class: Well drained very gravelly loam, brown (10YR 5/3) moist; weak Permeability: Moderate (0.6 to 2.0 inches/hour) medium subangular blocky structure; slightly Landform: Escarpment, fan, hill, stream terrace, hard, very friable, slightly sticky, slightly plastic; terrace, swale on fan, swale on moraine few very fine roots; few very fine pores; common Parent material: Gravelly alluvium or glacial fluvial carbonate coats on undersides of rock fragments; deposits 45 percent gravel; 5 percent cobbles; violently Slope range: 0 to 60 percent effervescent; moderately alkaline (pH 8.2); Elevation range: 4,200 to 6,200 feet gradual smooth boundary. Mean annual precipitation: 15 to 20 inches Bk2—25 to 60 inches; light brownish gray (10YR 6/2) Mean annual air temperature: 39 to 45 degrees F extremely gravelly loam, brown (10YR 5/3) moist; Frost-free period: 70 to 115 days weak fine and medium subangular blocky structure; slightly hard, very friable, slightly sticky, Taxonomic Class: Loamy-skeletal, mixed, slightly plastic; few very fine roots; few very fine superactive, frigid Typic Argiustolls pores; common carbonate coats on undersides of rock fragments; 50 percent gravel; 15 percent Typical Pedon cobbles; violently effervescent; moderately Shawmut gravelly loam, in an area of Shawmut alkaline (pH 8.2). gravelly loam, 2 to 8 percent slopes, in an area of Range in Characteristics rangeland, 800 feet north and 1,400 feet east of the southwest corner of sec. 6, T. 1 S., R. 16 E.; USGS Soil temperature: 41 to 47 degrees F Greycliff topographic quadrangle (lat. 45o46'12" N.; Moisture control section: Between 4 and 12 inches long. 109o48'06" W.) Thickness of the mollic epipedon: 7 to 16 inches Depth to the calcic horizon: 10 to 20 inches A—0 to 3 inches; very dark grayish brown (10YR 3/2) Note: Some pedons do not have a Btk horizon. gravelly loam, very dark brown (10YR 2/2) moist; moderate fine granular structure; slightly hard, A horizon very friable, slightly sticky, slightly plastic; Hue: 7.5YR or 10YR common very fine and fine roots; common very Value: 3 or 4 dry; 2 or 3 moist fine pores; 20 percent gravel; neutral (pH 7.0); Chroma: 2 or 3 abrupt smooth boundary. Texture (less than 2 mm): Loam 128 Soil Survey

Clay content: 15 to 27 percent Sieben Series Content of rock fragments: 15 to 80 percent—0 to 30 percent stones and cobbles; 15 to Depth class: Very deep (greater than 60 inches) 50 percent gravel Drainage class: Well drained Reaction: pH 6.6 to 7.3 Permeability: Moderate (0.6 to 2.0 inches/hour) Landform: Fan, stream terrace, and terrace Bt horizon Parent material: Gravelly alluvium Hue: 7.5YR or 10YR Slope range: 2 to 15 percent Value: 3 to 5 dry; 2 to 4 moist Elevation range: 3,750 to 5,200 feet Chroma: 2 to 4 Mean annual precipitation: 10 to 14 inches Texture (less than 2 mm): Clay loam or sandy Mean annual air temperature: 43 to 46 degrees F clay loam Frost-free period: 95 to 125 days Clay content: 20 to 35 percent Content of rock fragments: 35 to 80 percent—0 to Taxonomic Class: Loamy-skeletal, mixed, 35 percent stones and cobbles; 30 to superactive, frigid Calcidic Argiustolls 45 percent gravel Reaction: pH 6.6 to 7.8 Typical Pedon Btk horizon: Sieben gravelly loam, 1,900 feet south and 50 feet Hue: 7.5YR or 10YR east of the northwest corner of sec. 15, T. 13 N., Value: 3 to 6 dry; 2 to 5 moist R. 4 W.; Lewis and Clark County, Montana. Chroma: 2 to 4 Texture (less than 2 mm): Clay loam, loam, sandy A1—0 to 5 inches; grayish brown (10YR 5/2) gravelly clay loam, or sandy loam loam, very grayish brown (10YR 3/2) moist; Clay content: 18 to 30 percent moderate very thin platy structure parting to Content of rock fragments: 35 to 80 percent—0 to moderate very fine granular; slightly hard, very 40 percent stones and cobbles; 30 to friable, slightly sticky, slightly plastic; many very 60 percent gravel fine roots; 20 percent angular gravel; slightly acid Calcium carbonate equivalent: 15 to 30 percent (pH 6.2); clear smooth boundary. Reaction: pH 6.6 to 7.9 A2—5 to 9 inches; grayish brown (10YR 5/2) gravelly loam, very dark grayish brown (10YR 3/2) moist; Bk1 horizon moderate medium prismatic structure parting to Hue: 10YR or 2.5Y moderate fine and medium subangular blocky; Value: 5 to 7 dry; 4 to 6 moist slightly hard, very friable, slightly sticky, slightly Chroma: 2 to 4 plastic; many very fine roots; many very fine Texture (less than 2 mm): Loam, sandy loam, tubular and interstitial pores; 20 percent angular sandy clay loam, or clay loam gravel; slightly acid (pH 6.2); clear smooth Clay content: 18 to 30 percent boundary. Content of rock fragments: 35 to 80 percent—0 to Bt1—9 to 17 inches; pale brown (10YR 6/3) very 40 percent stones and cobbles; 30 to gravelly clay loam, dark brown (10YR 4/3) moist; 60 percent gravel moderate medium prismatic structure parting to Calcium carbonate equivalent: 15 to 30 percent moderate fine and medium subangular blocky; Reaction: pH 7.9 to 8.4 hard, friable, moderately sticky, moderately Bk2 horizon plastic; common very fine roots; many very Hue: 10YR or 2.5Y fine tubular and interstitial pores; many distinct Value: 5 to 8 dry; 4 to 7 moist brown (10YR 5/3) clay films on faces of peds; Chroma: 2 to 4 45 percent angular gravel; slightly acid (pH 6.4); Texture (less than 2 mm): Loam, sandy loam, or gradual smooth boundary. sandy clay loam Bt2—17 to 21 inches; pale brown (10YR 6/3) very Clay content: 5 to 25 percent gravelly loam, dark brown (10YR 4/3) moist; weak Content of rock fragments: 50 to 85 percent—0 to fine subangular blocky structure; slightly hard, 40 percent stones and cobbles; 45 to very friable, moderately sticky, slightly plastic; 70 percent gravel common very fine roots; many very fine tubular Calcium carbonate equivalent: 10 to 25 percent and interstitial pores; few faint clay films on faces Reaction: pH 7.9 to 9.0 of peds and rock fragments; 55 percent angular Sweet Grass County Area, Montana—Part I 129

gravel; 5 percent angular cobbles; few faint Texture (less than 2 mm): Clay loam or sandy carbonate coatings on undersides of rock clay loam fragments; slightly alkaline (pH 7.8); gradual Clay content: 30 to 35 percent smooth boundary. Content of rock fragments: 35 to 60 percent—0 to Bk1—21 to 30 inches; very pale brown (10YR 7/3) 5 percent stones; 0 to 5 percent angular very gravelly loam, pale brown (10YR 6/3) moist; cobbles; 35 to 50 percent angular gravel weak fine and medium subangular blocky Reaction: pH 6.6 to 7.3 structure; slightly hard, very friable, slightly sticky, Bt2 horizon slightly plastic; common very fine roots; many Hue: 10YR or 2.5Y very fine tubular and interstitial pores; 45 percent Value: 5 or 6 dry angular gravel; 10 percent angular cobbles; Chroma: 3 or 4 continuous distinct lime casts on undersides of Texture (less than 2 mm): Loam or sandy loam fragments; many fine seams and masses of Clay content: 15 to 25 percent lime; violently effervescent; moderately alkaline Content of rock fragments: 40 to 70 percent—0 to (pH 8.0); gradual smooth boundary. 5 percent angular cobbles; 35 to 65 percent Bk2—30 to 41 inches; very pale brown (10YR 7/3) angular gravel extremely gravelly loam, yellowish brown (10YR Reaction: pH 6.6 to 7.8 5/4) moist; massive; slightly hard, very friable, slightly sticky, slightly plastic; few very fine roots; Bk1 and Bk2 horizons 55 percent angular gravel; 20 percent angular Hue: 10YR or 2.5Y cobbles; continuous prominent lime casts on rock Value: 5 to 7 dry; 4 to 6 moist fragments; lime cemented sand and fine gravel Chroma: 2 to 4 on undersides of some fragments; violently Texture (less than 2 mm): Loam, sandy loam, or effervescent; moderately alkaline (pH 8.0); coarse sandy loam gradual smooth boundary. Clay content: 10 to 25 percent Bk3—41 to 60 inches; pale brown (10YR 6/3) Content of rock fragments: 50 to 80 percent—5 to extremely gravelly sandy loam, dark brown 20 percent angular cobbles; 45 to 60 percent (10YR 4/3) moist; massive; slightly hard, very angular gravel friable, slightly sticky, slightly plastic; 60 percent Calcium carbonate equivalent: 15 to 25 percent angular gravel; 15 percent angular cobbles; Reaction: pH 7.9 to 8.4 continuous faint lime casts on undersides of rock Bk3 horizon fragments; strongly effervescent; moderately Hue: 10YR or 2.5Y alkaline (pH 8.0). Value: 6 or 7 dry; 4 or 5 moist Chroma: 2 to 4 Range in Characteristics Texture (less than 2 mm): Sandy loam or loam Clay content: 5 to 15 percent Soil temperature: 42 to 47 degrees F Content of rock fragments: 50 to 80 percent—5 to Moisture control section: Between 4 and 12 inches 20 percent angular cobbles; 45 to 60 percent Thickness of the mollic epipedon: 7 to 10 inches angular gravel Depth to the Bk horizon: 15 to 25 inches Calcium carbonate equivalent: 15 to 25 percent A horizons Reaction: pH 7.4 to 8.4 Hue: 10YR or 2.5Y Chroma: 2 or 3 Texture (less than 2 mm): Loam Sinnigam Series Clay content: 15 to 25 percent Depth class: Shallow (10 to 20 inches) Content of rock fragments: 10 to 60 percent—0 to Drainage class: Well drained 10 percent stones; 0 to 20 percent angular Permeability: Moderately slow (0.2 to 0.6 inch/hour) cobbles; 10 to 30 percent angular gravel Landform: Hill Reaction: pH 6.1 to 7.3 Parent material: Clayey residuum weathered from Bt1 horizon sandstone and shale Hue: 10YR or 2.5Y Slope range: 15 to 45 percent Value: 4 to 6 dry; 3 or 4 moist Elevation range: 4,200 to 6,000 feet Chroma: 3 or 4 Mean annual precipitation: 15 to 19 inches 130 Soil Survey

Mean annual air temperature: 43 to 45 degrees F Chroma: 2 or 3 Frost-free period: 85 to 115 days Texture (less than 2 mm): Clay loam Clay content: 27 to 35 percent Taxonomic Class: Clayey-skeletal, mixed, Content of rock fragments: 5 to 50 percent—0 to superactive, frigid Lithic Argiustolls 30 percent stones and cobbles; 5 to 40 percent channers Typical Pedon Reaction: pH 6.1 to 7.8 Sinnigam very channery clay loam, in an area of Bt1 horizon Sinnigam-Wayden complex, moist, 15 to 45 percent Hue: 7.5YR or 10YR slopes, in an area of coniferous forest, 2,500 feet Value: 4 or 5 dry; 2 or 3 moist north and 1,850 feet east of the southwest corner of Chroma: 2 or 3 sec. 11, T. 1 S., R. 16 E.; USGS Lone Indian Butte Texture (less than 2 mm): Clay, silty clay, or clay topographic quadrangle (lat. 45o45'42" N.; long. loam 109o43'08" W.) Clay content: 35 to 50 percent Content of rock fragments: 35 to 70 percent—5 to Oi—0 to 1 inch; slightly decomposed needles, twigs, 20 percent stones and cobbles; 30 to and grass. 60 percent channers A—1 to 5 inches; grayish brown (10YR 5/2) very Reaction: pH 6.1 to 7.8 channery clay loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; Bt2 horizon soft, very friable, slightly sticky, moderately Hue: 7.5YR or 10YR plastic; many very fine and fine roots; many fine Value: 5 or 6 dry; 4 or 5 moist pores; 40 percent channers; neutral (pH 6.6); Chroma: 2 to 4 abrupt smooth boundary. Texture (less than 2 mm): Clay, silty clay, or clay Bt1—5 to 12 inches; grayish brown (10YR 5/2) very loam channery clay, dark brown (10YR 3/3) moist; Clay content: 35 to 50 percent moderate fine and medium subangular blocky Content of rock fragments: 35 to 70 percent—5 to structure; moderately hard, friable, very sticky, 20 percent stones and cobbles; 30 to moderately plastic; many very fine and fine roots; 65 percent channers common medium and many fine pores; many Reaction: pH 6.1 to 7.8 distinct continuous dark yellowish brown (10YR 3/4) moist; clay films on faces of peds and rock fragments; 40 percent channers; 5 percent Sixbeacon Series cobbles; neutral (pH 6.8); clear smooth boundary. Depth class: Very deep (greater than 60 inches) Bt2—12 to 19 inches; pale brown (10YR 6/3) very Drainage class: Well drained channery clay, brown (10YR 5/3) moist; moderate Permeability: In the upper 0 to 24 inches = moderate medium and coarse subangular blocky structure; (0.6 to 2.0 inches/hour); below this depth = rapid very hard, firm, very sticky, very plastic; many (6 to 20 inches/hour) very fine and fine roots; common medium pores; Landform: Fan, stream terrace, terrace, and fan on common distinct discontinuous brown (10YR 5/3) escarpment moist; clay films on faces of peds and rock Parent material: Gravelly alluvium fragments; 45 percent channers; 10 percent Slope range: 2 to 60 percent cobbles; neutral (pH 7.2); abrupt wavy boundary. Elevation range: 3,750 to 5,200 feet R—19 inches; hard, fractured argillaceous Mean annual precipitation: 10 to 14 inches sandstone. Mean annual air temperature: 43 to 46 degrees F Range in Characteristics Frost-free period: 95 to 125 days Soil temperature: 42 to 47 degrees F Taxonomic Class: Loamy-skeletal, mixed, Moisture control section: Between 4 and 12 inches superactive, frigid Aridic Haplustolls Thickness of the mollic epipedon: 7 to 12 inches Depth to bedrock: 10 to 20 inches Typical Pedon A horizon Sixbeacon gravelly loam, 100 feet north and Hue: 7.5YR or 10YR 1,000 feet west of the southeast corner of sec. 23, Value: 4 or 5 dry; 2 or 3 moist T. 8 N., R. 9 W.; Powell County, Montana. Sweet Grass County Area, Montana—Part I 131

Ap—0 to 4 inches; grayish brown (10YR 5/2) gravelly Texture (less than 2 mm): Loam or sandy loam loam, very dark grayish brown (10YR 3/2) moist; Clay content: 19 to 27 percent moderate fine granular structure; soft, very Content of rock fragments: 0 to 35 percent—0 to friable, nonsticky, nonplastic; many fine roots; 10 percent cobbles; 0 to 25 percent gravel many fine irregular pores; 15 percent gravel; Reaction: pH 6.6 to 8.4 neutral (pH 6.8); abrupt smooth boundary. Bk1 horizon Bw—4 to 10 inches; brown (10YR 5/3) loam, dark Hue: 10YR or 2.5Y brown (10YR 3/3) moist; moderate medium Value: 5 to 8 dry, 4 to 7 moist subangular blocky structure; hard, friable, slightly Chroma: 1 to 4 sticky, slightly plastic; many fine roots; many very Texture (less than 2 mm): Loam or sandy loam fine and fine tubular pores; 5 percent gravel; Clay content: 20 to 27 percent neutral (pH 7.2); clear wavy boundary. Content of rock fragments: 5 to 35 percent—0 to Bk1—10 to 12 inches; light brownish gray (10YR 6/2) 5 percent cobbles; 5 to 30 percent gravel loam, brown (10YR 5/3) moist; weak fine and Calcium carbonate equivalent: 5 to 25 percent medium subangular blocky structure; slightly Reaction: pH 6.6 to 8.4 hard, very friable, slightly sticky, slightly plastic; common fine roots; many very fine and fine 2Bk2 horizon pores; 10 percent gravel; disseminated lime; Hue: 10YR or 2.5Y strongly effervescent; moderately alkaline Value: 6 to 8 dry; 6 or 7 moist (pH 8.0); clear wavy boundary. Chroma: 2 to 4 2Bk2—12 to 24 inches; white (10YR 8/2) very Texture (less than 2 mm): Sandy loam or loam gravelly sandy loam, light gray (10YR 7/2) moist; Clay content: 10 to 20 percent weak fine subangular blocky structure; slightly Content of rock fragments: 35 to 60 percent—0 to hard, very friable, nonsticky, nonplastic; common 10 percent cobbles; 35 to 50 percent gravel fine roots; many very fine and fine tubular pores; Calcium carbonate equivalent: 20 to 40 percent 50 percent gravel; disseminated lime; violently Reaction: pH 7.9 to 8.4 effervescent; moderately alkaline (pH 8.4); clear 3Bk3 horizon wavy boundary. Value: 5 to 7 dry; 4 to 6 moist 3Bk3—24 to 60 inches; light gray (10YR 7/2) Chroma: 2 to 4 extremely gravelly loamy sand, pale brown (10YR Texture (less than 2 mm): Loamy sand, sandy 6/3) moist; single grain; loose, nonsticky, loam, or loam nonplastic; few fine roots; many fine irregular Clay content: 0 to 7 percent pores; 60 percent gravel; 10 percent cobbles; Content of rock fragments: 50 to 80 percent— disseminated lime; violently effervescent; 10 to 20 percent cobbles; 40 to 60 percent moderately alkaline (pH 8.4). gravel Range in Characteristics Calcium carbonate equivalent: 15 to 30 percent Reaction: pH 7.4 to 8.4 Soil temperature: 41 to 46 degrees F Moisture control section: Between 4 and 12 inches Thickness of the mollic epipedon: 7 to 15 inches Soapcreek Series Depth to the Bk horizon: 8 to 13 inches Depth class: Very deep (greater than 60 inches) Ap horizon Drainage class: Somewhat poorly drained Hue: 10YR or 2.5Y Permeability: Slow (0.06 to 0.20 inch/hour) Chroma: 2 or 3 Landform: Flood plain and flood-plain step Texture (less than 2 mm): Loam Parent material: Clayey alluvium Clay content: 20 to 27 percent Slope range: 0 to 2 percent Content of rock fragments: 0 to 35 percent—0 to Elevation range: 3,750 to 6,200 feet 15 percent cobbles; 0 to 20 percent gravel Mean annual precipitation: 10 to 20 inches Reaction: pH 6.1 to 7.8 Mean annual air temperature: 39 to 46 degrees F Bw horizon Frost-free period: 70 to 125 days Hue: 10YR or 2.5Y Value: 4 to 6 dry; 3 or 4 moist Taxonomic Class: Fine, mixed, superactive, frigid Chroma: 2 to 4 Fluvaquentic Haplustolls 132 Soil Survey

Typical Pedon sticky, slightly plastic; few fine roots; 10 percent gravel; violently effervescent; slightly alkaline Soapcreek clay loam, in an area of Soapcreek clay (pH 7.6); clear smooth boundary. loam, 0 to 2 percent slopes, in an area of hayland, 2Cg—48 to 60 inches; olive gray (5Y 5/2) very 800 feet south and 400 feet west of the northeast gravelly sandy clay loam, olive gray (5Y 4/2) corner of sec. 19, T. 4 N., R. 15 E.; USGS Melville moist; common medium and coarse prominent topographic quadrangle (lat. 46o05'14" N.; long. olive yellow (2.5Y 6/6) moist, redox 109o53'47" W.) concentrations; massive; very hard, friable, moderately sticky, moderately plastic; 35 percent Ap—0 to 4 inches; gray (10YR 5/1) clay loam, very gravel; 5 percent cobbles; violently effervescent; dark gray (10YR 3/1) moist; moderate fine and slightly alkaline (pH 7.6). medium granular structure; slightly hard, friable, moderately sticky, moderately plastic; common Range in Characteristics medium and many very fine and fine roots; many Soil temperature: 41 to 47 degrees F very fine and fine pores; strongly effervescent; Moisture control section: Between 4 and 12 inches moderately alkaline (pH 8.4); abrupt smooth Thickness of the mollic epipedon: 10 to 15 inches boundary. Depth to the seasonal high water table: 24 to A1—4 to 8 inches; gray (2.5Y 5/1) clay loam, very 42 inches dark gray (2.5Y 3/1) moist; moderate medium Depth to the 2Cg horizon: Greater than 40 inches angular blocky structure; moderately hard, firm, Note: Some pedons do not have a 2Cg horizon. moderately sticky, moderately plastic; common medium and many very fine and fine roots; A horizons common very fine pores; strongly effervescent; Hue: 10YR or 2.5Y moderately alkaline (pH 8.4); clear smooth Value: 3 to 5 dry; 2 or 3 moist boundary. Chroma: 1 or 2 A2—8 to 14 inches; gray (10YR 5/1) silty clay, very Texture (less than 2 mm): Clay loam dark gray (10YR 3/1) moist; moderate medium Clay content: 27 to 35 percent angular blocky structure; very hard, firm, very Content of rock fragments: 0 to 15 percent gravel sticky, very plastic; common medium and many Electrical conductivity: 0 to 4 mmhos/cm very fine and fine roots; common very fine pores; Reaction: pH 7.4 to 8.4 strongly effervescent; moderately alkaline Bk horizon (pH 8.4); clear smooth boundary. Hue: 10YR, 2.5Y, or 5Y Bk—14 to 25 inches; gray (10YR 6/1) silty clay, dark Value: 4 to 6 dry; 3 to 5 moist gray (10YR 4/1) moist; moderate coarse prismatic Chroma: 1 or 2 structure parting to moderate fine and medium Texture (less than 2 mm): Silty clay or silty clay angular blocky; very hard, firm, very sticky, very loam plastic; few medium and common very fine and Clay content: 35 to 50 percent fine roots; common very fine and fine pores; Content of rock fragments: 0 to 15 percent gravel common fine irregular masses of lime; strongly Calcium carbonate equivalent: 1 to 15 percent effervescent; moderately alkaline (pH 8.2); clear Electrical conductivity: 0 to 4 mmhos/cm smooth boundary. Reaction: pH 7.4 to 8.4 Bkg—25 to 34 inches; gray (2.5Y 6/1) clay, dark gray (2.5Y 4/1) moist; common medium prominent Bkg horizon olive yellow (2.5Y 6/8) moist, redox Hue: 10YR, 2.5Y, or 5Y concentrations; moderate coarse prismatic Value: 5 or 6 dry; 4 moist structure; very hard, firm, very sticky, very plastic; Chroma: 1 or 2 few medium and common fine roots; many fine Redox concentrations: Few to many; chroma of 6 and medium irregular masses of lime; violently or 8 effervescent; slightly alkaline (pH 7.8); clear Texture (less than 2 mm): Clay, silty clay, or silty smooth boundary. clay loam Bg1—34 to 48 inches; light olive gray (5Y 6/2) clay Clay content: 35 to 50 percent loam, olive gray (5Y 5/2) moist; common medium Content of rock fragments: 0 to 15 percent gravel and coarse prominent olive yellow (2.5Y 6/6) Calcium carbonate equivalent: 1 to 15 percent moist, redox concentrations; weak coarse Electrical conductivity: 0 to 4 mmhos/cm prismatic structure; very hard, friable, slightly Reaction: pH 7.4 to 8.4 Sweet Grass County Area, Montana—Part I 133

Bg horizon T. 3 S., R. 13 E.; USGS McLeod Basin topographic Hue: 2.5Y or 5Y quadrangle (lat. 45o33'18" N.; long. 110o10'07" W.) Value: 5 or 6 dry; 4 or 5 moist Oi—0 to 2 inches; partially decayed needles and Chroma: 1 or 2 twigs. Redox concentrations: Few to many; chroma of 6 E1—2 to 8 inches; brown (10YR 5/3) very cobbly or 8 loam, brown (10YR 4/3) moist; weak medium Redox depletions: None to common; chroma of 0 platy structure parting to weak fine and medium or 1 granular; soft, very friable, nonsticky, nonplastic; Texture (less than 2 mm): Clay loam, silty clay, or common medium and many very fine and clay fine roots; common very fine and fine pores; Clay content: 25 to 45 percent 15 percent gravel; 15 percent cobbles; 5 percent Content of rock fragments: 0 to 15 percent gravel stones; moderately acid (pH 6.0); clear wavy Calcium carbonate equivalent: 1 to 15 percent boundary. Electrical conductivity: 0 to 4 mmhos/cm E2—8 to 28 inches; light gray (10YR 7/2) very cobbly Reaction: pH 7.4 to 8.4 loam, light brownish gray (10YR 6/2) moist; weak 2Cg horizon: fine and medium granular structure; soft, very Hue: 2.5Y or 5Y friable, nonsticky, nonplastic; common very fine to Value: 5 to 7 dry; 4 or 5 moist medium roots; many very fine and fine pores; Chroma: 1 or 2 20 percent gravel; 25 percent cobbles; 5 percent Redox concentrations: Few to many; chroma of 6 stones; slightly acid (pH 6.4); clear wavy or 8 boundary. Redox depletions: None to common; chroma of 0 E/Bt—28 to 37 inches; E part (70 percent) light gray or 1 (10YR 7/2) very cobbly loam, light brownish gray Texture (less than 2 mm): Sandy clay loam, clay (10YR 6/2) moist tongues; Bt part (30 percent) loam, or clay yellowish brown (10YR 5/6) very cobbly sandy Clay content: 25 to 45 percent clay loam, dark yellowish brown (10YR 4/6) Content of rock fragments: 15 to 60 percent—0 to moist; weak fine and medium prismatic structure 10 percent cobbles; 15 to 50 percent gravel parting to moderate medium subangular blocky; Calcium carbonate equivalent: 1 to 15 percent slightly hard, friable, slightly sticky, slightly plastic; Electrical conductivity: 0 to 4 mmhos/cm few very fine roots; common very fine and fine Reaction: pH 7.4 to 8.4 pores; 20 percent gravel; 25 percent cobbles; 5 percent stones; neutral (pH 6.6); gradual smooth boundary. Stemple Series Bt—37 to 62 inches; yellowish brown (10YR 5/6) very cobbly sandy clay loam, dark yellowish brown Depth class: Very deep (greater than 60 inches) (10YR 4/6) moist; moderate medium and coarse Drainage class: Well drained subangular blocky structure; very hard, firm, Permeability: Moderate (0.6 to 2.0 inches/hour) moderately sticky, moderately plastic; few very Landform: Mountain fine roots; common very fine pores; common Parent material: Gravelly colluvium or gravelly till distinct discontinuous brown (7.5YR 4/4) moist; Slope range: 25 to 70 percent clay films on faces of peds and rock fragments; Elevation range: 5,500 to 7,500 feet 20 percent gravel; 20 percent cobbles; 5 percent Mean annual precipitation: 20 to 25 inches stones; neutral (pH 6.6). Mean annual air temperature: 36 to 38 degrees F Range in Characteristics Frost-free period: 50 to 70 days Soil temperature: 36 to 42 degrees F Taxonomic Class: Loamy-skeletal, mixed, Moisture control section: Between 4 and 12 inches superactive Typic Palecryalfs Depth to the Bt horizon: 25 to 50 inches Typical Pedon E1 horizon Stemple very cobbly loam, in an area of Stemple- Hue: 7.5YR, 10YR, or 2.5Y Worock complex, 35 to 70 percent slopes, very stony, Value: 5 to 7 dry; 4 to 6 moist in an area of coniferous forest, 700 feet north and Chroma: 2 or 3 2,000 feet east of the southwest corner of sec. 19, Texture (less than 2 mm): Loam or sandy loam 134 Soil Survey

Clay content: 10 to 20 percent Mean annual air temperature: 43 to 46 degrees F Content of rock fragments: 20 to 60 percent—5 to Frost-free period: 85 to 130 days 25 percent stones, flagstones, or cobbles; 15 to 45 percent gravel or channers Taxonomic Class: Loamy-skeletal, mixed, Reaction: pH 5.1 to 6.5 superactive, frigid Typic Endoaquolls E2 horizon Typical Pedon Hue: 7.5YR, 10YR, or 2.5Y Value: 6 to 8 dry; 4 to 6 moist Swampcreek gravelly sandy clay loam, in an area of Chroma: 2 or 3 Roy-Swampcreek complex, 0 to 4 percent slopes, in Texture (less than 2 mm): Loam or sandy loam an area of rangeland, 1,500 feet south and 100 feet Clay content: 10 to 20 percent east of the northwest corner of sec. 32, T. 5 N., Content of rock fragments: 35 to 80 percent— R. 14 E.; USGS Porcupine Butte topographic 15 to 30 percent stones, flagstones, or quadrangle (lat. 46o08'36" N.; long. 110o00'28" W.) cobbles; 20 to 60 percent gravel or channers A—0 to 8 inches; dark grayish brown (10YR 4/2) Reaction: pH 5.1 to 6.5 gravelly sandy clay loam, very dark grayish brown E/Bt horizons (10YR 3/2) moist; weak fine granular structure; Hue: 7.5YR, 10YR, or 2.5Y slightly hard, friable, slightly sticky, moderately Value: E part—6 or 7, Bt part—5 or 6 dry; plastic; many very fine to medium roots; common E part—4 to 6, Bt part—4 or 5 moist very fine and fine pores; 5 percent cobbles; Chroma: E part—2 or 3; Bt part—4 to 6 25 percent gravel; slightly alkaline (pH 7.8); Texture (less than 2 mm): Loam, clay loam, or abrupt smooth boundary. sandy clay loam Bw—8 to 18 inches; grayish brown (10YR 5/2) loam, Clay content: 15 to 30 percent dark grayish brown (10YR 4/2) moist; common Content of rock fragments: 35 to 80 percent— medium and coarse prominent strong brown 15 to 40 percent stones, flagstones, or (7.5YR 5/6) moist, redox concentrations; few fine cobbles; 20 to 40 percent gravel distinct gray (10YR 5/1) moist, redox depletions; Reaction: pH 5.1 to 7.3 weak medium prismatic structure parting to moderate fine and medium subangular blocky; Bt horizon slightly hard, friable, slightly sticky, slightly Hue: 7.5YR, 10YR, or 2.5Y plastic; common very fine and fine and many Value: 5 to 7 dry; 4 or 5 moist medium roots; common very fine and fine pores; Chroma: 3, 4, or 6 10 percent gravel; moderately alkaline (pH 7.2); Texture (less than 2 mm): Sandy clay loam or clay gradual smooth boundary. loam 2Bkg1—18 to 30 inches; grayish brown (2.5Y 5/2) Clay content: 27 to 35 percent very gravelly coarse sandy loam, dark grayish Content of rock fragments: 35 to 80 percent—0 to brown (2.5Y 4/2) moist; common fine distinct 10 percent stones and flagstones; 15 to dark yellowish brown (10YR 4/6) moist, redox 30 percent cobbles; 20 to 40 percent gravel concentrations; weak fine and medium angular Reaction: pH 5.6 to 7.3 blocky structure; soft, very friable, nonsticky, nonplastic; common fine and medium roots; few Swampcreek Series medium and many very fine and fine pores; common fine irregular masses of lime; common Depth class: Very deep (greater than 60 inches) distinct carbonate coats on undersides of rock Drainage class: Poorly drained fragments; 35 percent gravel; 5 percent cobbles; Permeability: Moderate (0.6 to 2.0 inches/hour) strongly effervescent; moderately alkaline Landform: Flood plain, stream terrace, swale on (pH 8.4); clear smooth boundary. terrace 3Bkg2—30 to 60 inches; light gray (5Y 6/1) extremely Parent material: Loamy over gravelly alluvium gravelly loamy coarse sand, olive gray (5Y 4/2) Slope range: 0 to 4 percent moist; single grain; loose, nonsticky, nonplastic; Elevation range: 3,750 to 6,000 feet few fine roots; common fine soft masses of lime; Mean annual precipitation: 10 to 19 inches common distinct carbonate coats on undersides Sweet Grass County Area, Montana—Part I 135

of rock fragments; 50 percent gravel; 15 percent 3Bkg horizon cobbles; strongly effervescent; moderately Hue: 5Y, 2.5Y, or N alkaline (pH 8.4). Value: 5 to 7 dry; 4 to 6 moist Chroma: 0 to 2 Range in Characteristics Texture (less than 2 mm): Loamy coarse sand, Soil temperature: 42 to 47 degrees F sand, coarse sand, or loamy sand Moisture control section: Between 4 and 12 inches Clay content: 1 to 10 percent Thickness of the mollic epipedon: 7 to 14 inches Content of rock fragments: 50 to 80 percent—0 to Depth to the 3Bk horizon: 20 to 40 inches 15 percent stones; 10 to 25 percent cobbles; Depth to the seasonal high water table: 8 to 40 to 55 percent gravel 24 inches Calcium carbonate equivalent: 5 to 15 percent Reaction: pH 7.4 to 8.4 A horizon Hue: 10YR or 2.5Y Value: 3 to 5 dry; 2 or 3 moist Chroma: 1 or 2 Sweetgrass Series Texture (less than 2 mm): Sandy clay loam or Depth class: Very deep (greater than 60 inches) loam Drainage class: Well drained Clay content: 18 to 35 percent Permeability: In the upper 0 to 28 inches = Content of rock fragments: 15 to 35 percent—0 to moderately slow (0.2 to 0.6 inch/hour); below this 5 percent cobbles; 15 to 30 percent gravel depth = rapid (6 to 20 inches/hour) Reaction: pH 6.6 to 7.8 Landform: Fan and terrace Bw horizon Parent material: Clayey over sandy and gravelly Hue: 10YR or 2.5Y alluvium Value: 4 to 6 dry; 3 to 5 moist Slope range: 0 to 8 percent Chroma: 2 Elevation range: 4,200 to 6,000 feet Redox concentrations: Few to many; chroma of 6 Mean annual precipitation: 15 to 19 inches or 8 Mean annual air temperature: 43 to 45 degrees F Redox depletions: None to common; chroma of 0 Frost-free period: 85 to 115 days or 1 Texture (less than 2 mm): Loam, sandy clay loam, Taxonomic Class: Clayey over sandy or sandy- or clay loam skeletal, smectitic over mixed, frigid Typic Clay content: 20 to 35 percent Argiustolls Content of rock fragments: 0 to 35 percent—0 to Typical Pedon 5 percent stones and cobbles; 0 to 30 percent gravel Sweetgrass gravelly loam, in an area of Sweetgrass Reaction: pH 6.6 to 8.4 gravelly loam, 0 to 4 percent slopes, in an area of rangeland, 1,450 feet south and 2,400 feet east of the 2Bkg horizon northwest corner of sec. 27, T. 1 N., R. 14 E.; USGS Hue: 2.5Y or 5Y Big Timber topographic quadrangle (lat. 45o48'39" N.; Value: 5 to 7 dry; 4 to 6 moist long. 109o58'11" W.) Chroma: 1 or 2 Redox concentrations: Few to many; chroma of 6 A—0 to 7 inches; dark grayish brown (10YR 4/2) or 8 gravelly loam, very dark grayish brown (10YR Redox depletions: None to common; chroma of 0 3/2) moist; weak fine granular structure; soft, very or 1 friable, slightly sticky, slightly plastic; common fine Texture (less than 2 mm): Coarse sandy loam, and medium roots; many very fine and fine pores; sandy loam, or loam 15 percent gravel; 2 percent cobbles; slightly Clay content: 5 to 20 percent alkaline (pH 7.4); abrupt smooth boundary. Content of rock fragments: 35 to 60 percent—5 to Bt—7 to 13 inches; brown (10YR 5/3) clay, dark 15 percent cobbles; 30 to 45 percent gravel brown (10YR 4/3) moist; moderate medium Calcium carbonate equivalent: 5 to 15 percent subangular blocky structure parting to weak fine Reaction: pH 7.4 to 8.4 subangular blocky; moderately hard, friable, 136 Soil Survey

moderately sticky, moderately plastic; many Texture (less than 2 mm): Loam, clay loam, or continuous distinct dark brown (7.5YR 3/2) moist; clay clay films on faces of peds and lining pores; few Clay content: 20 to 50 percent fine and medium roots; many very fine pores; Content of rock fragments: 0 to 25 percent—0 to 1 percent gravel; slightly alkaline (pH 7.6); abrupt 5 percent cobbles; 0 to 20 percent gravel smooth boundary. Reaction: pH 6.6 to 7.8 2Bk1—13 to 19 inches; light gray (10YR 7/2) sandy Bt horizon clay loam, pale brown (10YR 6/3) moist; weak Hue: 7.5YR or 10YR coarse prismatic structure; slightly hard, very Value: 4 to 6 dry; 3 to 5 moist friable, slightly sticky, slightly plastic; few fine Chroma: 2 to 4 roots; common fine pores; common large masses Texture (less than 2 mm): Clay loam or clay of lime; 5 percent gravel; violently effervescent; Clay content: 35 to 45 percent moderately alkaline (pH 8.4); clear smooth Content of rock fragments: 0 to 25 percent—0 to boundary. 5 percent cobbles; 0 to 20 percent gravel 2Bk2—19 to 28 inches; white (10YR 8/2) gravelly Reaction: pH 6.6 to 7.8 sandy loam, light gray (10YR 7/2) moist; weak coarse prismatic structure; soft, very friable, 2Bk horizons nonsticky, nonplastic; common fine and medium Hue: 10YR or 2.5Y pores; common large masses of lime; many Value: 5 to 8 dry; 4 to 7 moist distinct carbonate coats on rock fragments; Chroma: 2 to 4 15 percent gravel; 5 percent cobbles; violently Texture (less than 2 mm): Sandy clay loam, loam, effervescent; moderately alkaline (pH 8.4); clear clay loam, or sandy loam smooth boundary. Clay content: 10 to 30 percent 3Bk3—28 to 43 inches; light gray (10YR 7/2) very Content of rock fragments: 5 to 35 percent—0 to gravelly loamy coarse sand, yellowish brown 10 percent cobbles; 5 to 25 percent gravel (10YR 5/4) moist; single grain; loose, nonsticky, Calcium carbonate equivalent: 15 to 50 percent nonplastic; continuous distinct carbonate coats Reaction: pH 7.4 to 8.4 on undersides of rock fragments; 35 percent 3Bk horizon gravel; 10 percent cobbles; violently effervescent; Hue: 10YR or 2.5Y moderately alkaline (pH 8.4); gradual smooth Value: 5 to 7 dry; 4 to 6 moist boundary. Chroma: 2 to 4 3C—43 to 60 inches; pale brown (10YR 6/3) Texture (less than 2 mm): Loamy coarse sand, extremely gravelly coarse sand, yellowish brown loamy sand, sand, or coarse sand (10YR 5/4) moist; single grain; loose, nonsticky, Clay content: 0 to 10 percent nonplastic; few distinct carbonate coats on Content of rock fragments: 35 to 80 percent—0 to undersides of rock fragments; 45 percent gravel; 15 percent stones; 5 to 25 percent cobbles; 20 percent cobbles; 10 percent stones; strongly 30 to 45 percent gravel effervescent; moderately alkaline (pH 8.4). Calcium carbonate equivalent: 5 to 20 percent Reaction: pH 7.4 to 8.4 Range in Characteristics 3C horizon Soil temperature: 42 to 47 degrees F Hue: 10YR or 2.5Y Moisture control section: Between 4 and 12 inches Value: 5 to 7 dry; 4 to 6 moist Thickness of the mollic epipedon: 7 to 15 inches Chroma: 2 to 4 Depth to the 2Bk horizon: 10 to 20 inches Texture (less than 2 mm): Coarse sand, sand, or Depth to the 3Bk horizon: 20 to 40 inches loamy coarse sand A horizon Clay content: 0 to 10 percent Hue: 7.5YR or 10YR Content of rock fragments: 35 to 80 percent—0 to Value: 4 or 5 dry; 2 or 3 moist 15 percent stones; 5 to 25 percent cobbles; Chroma: 2 or 3 30 to 45 percent gravel Sweet Grass County Area, Montana—Part I 137

Calcium carbonate equivalent: 5 to 20 percent faint discontinuous dark yellowish brown (10YR Reaction: pH 7.4 to 8.4 3/4) moist; clay films on faces of peds; 5 percent gravel; slightly acid (pH 6.2); clear smooth boundary. Sweetweed Series Bt2—27 to 46 inches; pale brown (10YR 6/3) loam, brown (10YR 5/3) moist; moderate medium and Depth class: Very deep (greater than 60 inches) coarse subangular blocky structure; slightly hard, Drainage class: Well drained friable, moderately sticky, moderately plastic; Permeability: Moderate (0.6 to 2.0 inches/hour) common fine and medium roots; many very fine Landform: Hill and fine pores; common distinct discontinuous Parent material: Loamy alluvium or colluvium dark yellowish brown (10YR 4/4) moist; clay films Slope range: 25 to 60 percent on faces of peds and lining pores; 5 percent Elevation range: 3,900 to 6,200 feet gravel; slightly acid (pH 6.4); gradual smooth Mean annual precipitation: 15 to 20 inches boundary. Mean annual air temperature: 39 to 45 degrees F BC—46 to 61 inches; very pale brown (10YR 7/3) Frost-free period: 70 to 115 days channery loam, pale brown (10YR 6/3) moist; weak coarse prismatic structure; slightly hard, Taxonomic Class: Fine-loamy, mixed, superactive, friable, slightly sticky, slightly plastic; few medium frigid Typic Haplustalfs and coarse roots; many very fine and fine pores; Typical Pedon 15 percent channers; 5 percent cobbles; slightly acid (pH 6.4). Sweetweed loam, in an area of Vision-Sweetweed- Whitlash complex, 25 to 60 percent slopes, in an area Range in Characteristics of coniferous forest, 800 feet north and 2,400 feet east of the southwest corner of sec. 3, T. 2 S., Soil temperature: 38 to 47 degrees F R. 15 E.; USGS Packsaddle Butte topographic Moisture control section: Between 4 and 12 inches quadrangle (lat. 45o41'02" N.; long. 109o51'40" W.) Note: Some pedons do not have a BC horizon. Oi—0 to 1 inch; partially decomposed twigs and A horizon needles; moderately acid (pH 6.0). Hue: 7.5YR, 10YR, or 2.5Y A—1 to 7 inches; dark grayish brown (10YR 4/2) Value: 4 or 5 dry; 2 or 3 moist loam, very dark grayish brown (10YR 3/2) moist; Chroma: 2 or 3 weak fine granular structure; soft, very friable, Texture (less than 2 mm): Loam slightly sticky, nonplastic; many fine and medium Clay content: 18 to 27 percent roots; many very fine and fine pores; 2 percent Content of rock fragments: 0 to 15 percent gravel gravel; moderately acid (pH 6.0); clear smooth Reaction: pH 5.6 to 6.5 boundary. E/Bt horizons E/Bt—7 to 15 inches; E part (75 percent) light Hue: 7.5YR, 10YR, or 2.5Y brownish gray (10YR 6/2) loam, dark grayish Value: E part—5 to 7 dry, 4 or 5 moist; Bt part— brown (10YR 4/2) moist tongues; Bt part 4 to 6 dry, 3 to 5 moist (25 percent) pale brown (10YR 6/3) loam, brown Chroma: 2 to 4 (10YR 4/3) moist; weak fine granular structure; Texture (less than 2 mm): Loam or clay loam soft, very friable, slightly sticky, slightly plastic; Clay content: 18 to 35 percent many fine and medium roots; many very fine and Content of rock fragments: 0 to 15 percent gravel fine pores; common faint patchy dark yellowish Reaction: pH 5.6 to 7.3 brown (10YR 4/4) moist; clay films on subangular blocks of the Bt horizon; 2 percent gravel; Bt1 horizon moderately acid (pH 6.2); clear smooth boundary. Hue: 7.5YR, 10YR, or 2.5Y Bt1—15 to 27 inches; light brownish gray (10YR 6/2) Value: 5 or 6 dry; 4 or 5 moist loam, dark grayish brown (10YR 4/2) moist; Chroma: 2 to 4 moderate medium subangular blocky structure; Texture (less than 2 mm): Loam or clay loam slightly hard, friable, moderately sticky, Clay content: 18 to 35 percent moderately plastic; common fine and medium Content of rock fragments: 0 to 15 percent gravel roots; many very fine and fine pores; common Reaction: pH 5.6 to 7.3 138 Soil Survey

Bt2 horizon Bt—7 to 14 inches; brown (10YR 4/3) clay loam, very Hue: 7.5YR, 10YR, or 2.5Y dark brown (10YR 3/3) moist; strong medium Value: 5 to 7 dry; 4 or 5 moist subangular blocky structure; very hard, firm, very Chroma: 2 to 4 sticky, very plastic; common very fine and fine Texture (less than 2 mm): Loam, clay loam, or roots; many very fine to medium pores; common sandy clay loam distinct discontinuous dark yellowish brown Clay content: 18 to 35 percent (10YR 3/4) moist; clay films on faces of peds; Content of rock fragments: 5 to 15 percent gravel neutral (pH 7.2); clear wavy boundary. Reaction: pH 5.6 to 7.3 Bk1—14 to 28 inches; very pale brown (10YR 8/2) clay loam, light brownish gray (10YR 6/2) moist; BC horizon: moderate fine and medium subangular blocky Hue: 10YR or 2.5Y structure; moderately hard, friable, moderately Value: 5 to 7 dry; 4 to 6 moist sticky, moderately plastic; common very fine and Chroma: 2 to 4 fine roots; few very fine and fine pores; medium Texture (less than 2 mm): Loam, sandy loam, or and coarse soft masses of lime; violently fine sandy loam effervescent; strongly alkaline (pH 8.6); abrupt Clay content: 10 to 27 percent smooth boundary. Content of rock fragments: 5 to 35 percent—0 to 2Bk2—28 to 42 inches; light gray (10YR 7/2) very 10 percent cobbles; 5 to 25 percent gravel or gravelly loam, light brownish gray (10YR 6/2) channers moist; weak medium subangular blocky structure; Reaction: pH 5.6 to 7.3 soft, very friable, slightly sticky, slightly plastic; few very fine roots; common continuous carbonate coats on rock fragments; 30 percent Tamaneen Series gravel; 10 percent cobbles; violently effervescent; strongly alkaline (pH 8.6); gradual smooth Depth class: Very deep (greater than 60 inches) boundary. Drainage class: Well drained 2Bk3—42 to 60 inches; light gray (10YR 7/2) very Permeability: Moderately slow (0.2 to 0.6 inch/hour) gravelly sandy loam, light brownish gray (10YR Landform: Fan, stream terrace, and terrace 6/2) moist; weak fine subangular blocky structure; Parent material: Clayey over gravelly alluvium or slightly hard, very friable, nonsticky, nonplastic; clayey over gravelly glaciofluvial deposits common continuous carbonate coats rock Slope range: 0 to 8 percent fragments; 35 percent gravel; 15 percent cobbles; Elevation range: 4,200 to 6,200 feet violently effervescent; strongly alkaline (pH 8.6). Mean annual precipitation: 15 to 20 inches Mean annual air temperature: 39 to 45 degrees F Range in Characteristics Frost-free period: 70 to 115 days Soil temperature: 41 to 47 degrees F Moisture control section: Between 4 and 12 inches Taxonomic Class: Fine, smectitic, frigid Typic Thickness of the mollic epipedon: 7 to 15 inches Argiustolls Depth to the Bk horizon: 10 to 16 inches Typical Pedon Depth to the 2Bk horizon: 20 to 40 inches Tamaneen gravelly loam, in an area of Tamaneen A horizon gravelly loam, 0 to 2 percent slopes, in an area of Hue: 10YR or 2.5Y rangeland, 1,200 feet north and 2,600 feet west of Value: 4 or 5 dry; 2 or 3 moist the southeast corner of sec. 14, T. 1 S., R. 14 E.; Chroma: 2 or 3 USGS Ross Canyon topographic quadrangle Texture (less than 2 mm): Loam or clay loam (lat. 45o44'39" N.; long. 109o57'37" W.) Clay content: 20 to 35 percent Content of rock fragments: 0 to 35 percent—0 to A—0 to 7 inches; dark grayish brown (10YR 4/2) 10 percent cobbles; 0 to 25 percent gravel gravelly loam, very dark grayish brown (10YR Reaction: pH 6.6 to 7.8 3/2) moist; strong very fine and fine granular structure; moderately hard, friable, slightly sticky, Bt horizon slightly plastic; many very fine to coarse roots; Hue: 10YR or 2.5Y 15 percent gravel; neutral (pH 7.2); abrupt Value: 4 to 6 dry; 3 or 4 moist smooth boundary. Chroma: 2 or 3 Sweet Grass County Area, Montana—Part I 139

Texture (less than 2 mm): Clay loam, silty clay, Mean annual air temperature: 43 to 46 degrees F clay, or silty clay loam Frost-free period: 95 to 125 days Clay content: 35 to 50 percent Content of rock fragments: 0 to 15 percent—0 to Taxonomic Class: Fine, smectitic, frigid Aridic 5 percent cobbles; 0 to 10 percent gravel Argiustolls Reaction: pH 6.6 to 7.8 Typical Pedon Bk1 horizon Tanna clay loam, in an area of Tanna-Hinterland clay Hue: 10YR or 2.5Y loams, 2 to 8 percent slopes, in an area of rangeland, Value: 5 to 8 dry; 4 to 6 moist 2,200 feet north and 2,100 feet west of the southeast Chroma: 2 or 3 corner of sec. 23, T. 1 N., R. 16 E.; USGS Lone Indian Texture (less than 2 mm): Clay loam, silty clay, or Butte topographic quadrangle (lat. 45o49'07" N.; long. silty clay loam 109o41'56" W.) Clay content: 30 to 45 percent Content of rock fragments: 0 to 25 percent—0 to A—0 to 5 inches; grayish brown (10YR 5/2) clay 5 percent cobbles; 0 to 20 percent gravel loam, very dark grayish brown (10YR 3/2) moist; Calcium carbonate equivalent: 20 to 30 percent weak fine subangular blocky structure parting to Reaction: pH 7.4 to 9.0 moderate fine granular; slightly hard, friable, slightly sticky, slightly plastic; common very 2Bk2 horizon fine and fine roots; common fine pores; neutral Hue: 10YR or 2.5Y (pH 6.8); abrupt smooth boundary. Value: 6 to 8 dry; 4 to 7 moist Bt1—5 to 12 inches; brown (10YR 5/3) clay, dark Chroma: 2 to 4 brown (10YR 3/3) moist; moderate fine Texture (less than 2 mm): Loam or clay loam subangular blocky structure; moderately hard, Clay content: 18 to 35 percent firm, moderately sticky, moderately plastic; Content of rock fragments: 20 to 45 percent—0 to common very fine and fine roots; common 10 percent cobbles; 20 to 35 percent gravel fine pores; continuous distinct dark brown (10YR Calcium carbonate equivalent: 25 to 40 percent 4/3) moist; clay films on faces of peds; neutral Reaction: pH 7.9 to 9.0 (pH 7.0); gradual smooth boundary. 2Bk3 horizon Bt2—12 to 19 inches; grayish brown (10YR 5/2) clay Hue: 10YR or 2.5Y loam, dark grayish brown (10YR 4/2) moist; Value: 6 to 8 dry; 5 to 7 moist moderate medium prismatic structure parting to Chroma: 2 to 4 moderate fine subangular blocky structure; very Texture (less than 2 mm): Sandy loam, sandy hard, very firm, moderately sticky, moderately clay loam, or loam plastic; few fine roots; few fine pores; many Clay content: 8 to 25 percent distinct brown (10YR 4/3) moist; clay films on Content of rock fragments: 50 to 80 percent—5 to faces of peds; slightly alkaline (pH 7.4); clear 20 percent cobbles; 35 to 60 percent gravel smooth boundary. Calcium carbonate equivalent: 25 to 40 percent Bk—19 to 27 inches; light brownish gray (10YR 6/2) Reaction: pH 7.9 to 9.0 clay loam, brown (10YR 5/3) moist; weak coarse prismatic structure; moderately hard, firm, slightly sticky, slightly plastic; few fine roots; few very fine Tanna Series pores; common fine threads of lime; strongly effervescent; moderately alkaline (pH 8.2); clear Depth class: Moderately deep (20 to 40 inches) wavy boundary. Drainage class: Well drained Cr—27 to 60 inches; semiconsolidated shale Permeability: Slow (0.06 to 0.20 inch/hour) interbedded with layers of sandstone. Landform: Escarpment, fan, hill, strath terrace, Range in Characteristics terrace, and swale on plain Parent material: Clayey residuum weathered from Soil temperature: 40 to 47 degrees F sandstone and shale Moisture control section: Between 4 and 12 inches Slope range: 2 to 35 percent Thickness of the mollic epipedon: 7 to 12 inches Elevation range: 3,750 to 5,200 feet Depth to the Bk horizon: 10 to 20 inches Mean annual precipitation: 10 to 14 inches Depth to the Cr horizon: 20 to 40 inches 140 Soil Survey

A horizon corner of sec. 11, T. 35 N., R. 12 E.; Hill County, Hue: 10YR or 2.5Y Montana. Value: 5 dry; 2 or 3 moist A—0 to 2 inches; grayish brown (2.5Y 5/2) clay loam, Chroma: 2 or 3 dark grayish brown (2.5Y 4/2) moist; weak very Texture (less than 2 mm): Clay loam fine granular structure; soft, very friable, Clay content: 27 to 35 percent moderately sticky, moderately plastic; many very Content of rock fragments: 0 to 25 percent gravel fine roots; common very fine pores; strongly or channers alkaline (pH 8.8); clear smooth boundary. Calcium carbonate equivalent: 0 to 10 percent C—2 to 14 inches; grayish brown (2.5Y 5/2) clay loam Reaction: pH 6.6 to 7.8 consisting of thin layers of loam and fine sandy Bt horizons loam, dark grayish brown (2.5Y 4/2) moist; Hue: 10YR or 2.5Y massive; slightly hard, friable, moderately sticky, Value: 4 to 6 dry; 3 or 4 moist moderately plastic; many very fine roots; common Chroma: 2 or 3 very fine pores; strongly effervescent; strongly Texture (less than 2 mm): Clay loam, clay, or silty alkaline (pH 8.8); clear wavy boundary. clay Cyz—14 to 60 inches; light olive brown (2.5Y 5/4) Clay content: 35 to 50 percent clay loam consisting of thin layers of loam and Content of rock fragments: 0 to 10 percent gravel fine sandy loam, olive brown (2.5Y 4/4) moist; or channers many fine distinct yellowish brown (10YR 5/6) dry Electrical conductivity: 0 to 4 mmhos/cm redox concentrations below 20 inches and few Reaction: pH 6.6 to 8.4 faint above 20 inches; massive; hard, friable, moderately sticky, moderately plastic; few very Bk horizon fine roots; common very fine pores; common fine Hue: 10YR or 2.5Y masses and seams of gypsum and other salts; Value: 5 or 6 dry; 4 or 5 moist strongly effervescent; very strongly alkaline Chroma: 2 or 3 (pH 9.6). Texture (less than 2 mm): Clay loam, silty clay loam, or clay Range in Characteristics Clay content: 25 to 45 percent Soil temperature: 42 to 47 degrees F Content of rock fragments: 0 to 15 percent gravel Moisture control section: Between 4 and 12 inches or channers Depth to the seasonal high water table: 24 to Calcium carbonate equivalent: 5 to 15 percent 42 inches Electrical conductivity: 0 to 4 mmhos/cm Note: Gypsum and other salts are inherent in the Reaction: pH 7.4 to 8.4 parent material. A horizon Thibadeau Series Hue: 10YR or 2.5Y Value: 5 to 7 dry; 3 to 5 moist Depth class: Very deep (greater than 60 inches) Chroma: 2 to 4 Drainage class: Somewhat poorly drained Texture (less than 2 mm): Loam or clay loam Permeability: Moderately slow (0.2 to 0.6 inch/hour) Clay percent: 15 to 35 percent Landform: Flood plain Calcium carbonate equivalent: 1 to 5 percent Parent material: Loamy alluvium Electrical conductivity: 8 to 16 mmhos/cm Slope range: 0 to 4 percent Sodium adsorption ratio: 0 to 4 Elevation range: 3,750 to 5,200 feet Reaction: pH 7.4 to 9.0 Mean annual precipitation: 10 to 14 inches Mean annual air temperature: 43 to 46 degrees F C horizon Frost-free period: 95 to 125 days Hue: 10YR or 2.5Y Value: 5 or 6 dry; 4 or 5 moist Taxonomic Class: Fine-loamy, mixed, superactive, Chroma: 2 to 4 calcareous, frigid Oxyaquic Ustifluvents Texture (less than 2 mm): Clay loam, loam, or silty clay loam with or without thin strata of Typical Pedon loam, clay loam, silty clay loam, fine sandy Thibadeau clay loam, in an area of rangeland, loam, or silt loam 1,600 feet north and 600 feet east of the southwest Clay content: 18 to 35 percent Sweet Grass County Area, Montana—Part I 141

Calcium carbonate equivalent: 1 to 5 percent slightly plastic; few medium and many very fine Electrical conductivity: 8 to 16 mmhos/cm and fine roots; many very fine and fine pores; Sodium adsorption ratio: 0 to 20 25 percent gravel; 5 percent cobbles; slightly Reaction: pH 7.4 to 9.0 alkaline (pH 7.4); clear wavy boundary. Bk—10 to 60 inches; light brownish gray (10YR 6/2) Cyz horizon very gravelly loam, dark grayish brown (10YR Hue: 10YR or 2.5Y 4/2) moist; weak medium subangular blocky Value: 5 or 6 dry; 4 or 5 moist structure; soft, very friable, slightly sticky, slightly Chroma: 3 or 4 plastic; few very fine and fine roots; common very Texture (less than 2 mm): Clay loam, loam, or fine and fine pores; 35 percent gravel; 10 percent silty clay loam with or without thin strata of fine cobbles; carbonate coats on undersides of rock sandy loam, loam, clay loam, silty clay loam, or fragments; many fine and medium soft masses of silt loam lime; strongly effervescent; moderately alkaline Clay content: 18 to 35 percent (pH 8.2). Calcium carbonate equivalent: 1 to 5 percent Electrical conductivity: 8 to 16 mmhos/cm Range in Characteristics Sodium adsorption ratio: 0 to 30 Gypsum content: 2 to 5 percent Soil temperature: 36 to 45 degrees F Reaction: pH 7.4 to 9.0 Moisture control section: Between 4 and 12 inches Thickness of the mollic epipedon: 7 to 15 inches Tiban Series Depth to the Bk horizon: 10 to 24 inches Note: Some pedons have a C horizon. Depth class: Very deep (greater than 60 inches) A horizon Drainage class: Well drained Hue: 7.5YR or 10YR Permeability: Moderate (0.6 to 2.0 inches/hour) Value: 3 to 5 dry; 2 or 3 moist Landform: Stream terrace Chroma: 1 to 3 Parent material: Gravelly colluvium Texture (less than 2 mm): Loam Slope range: 0 to 8 percent Clay content: 18 to 27 percent Elevation range: 6,000 to 7,500 feet Content of rock fragments: 15 to 70 percent—0 to Mean annual precipitation: 20 to 25 inches 30 percent stones and cobbles; 15 to Mean annual air temperature: 36 to 43 degrees F 40 percent gravel or channers Frost-free period: 50 to 70 days Reaction: pH 6.6 to 7.3 Taxonomic Class: Loamy-skeletal, mixed, Bw horizon superactive Ustic Haplocryolls Hue: 7.5YR or 10YR Value: 4 to 6 dry; 3 or 4 moist Typical Pedon Chroma: 2 to 4 Tiban gravelly loam, in an area of Bearmouth-Tiban- Texture (less than 2 mm): Loam or clay loam Beehive complex, 0 to 8 percent slopes, in an area of Clay content: 18 to 35 percent coniferous forest, 1,700 feet south and 900 feet west Content of rock fragments: 15 to 60 percent—0 to of the northeast corner of sec. 25, T. 3 S., R. 13 E.; 20 percent stones and cobbles; 15 to USGS Squaw Peak topographic quadrangle (lat. 40 percent gravel or channers 45o32'56" N.; long. 110o03'24" W.) Reaction: pH 7.4 to 8.4 A—0 to 3 inches; dark grayish brown (10YR 4/2) Bk horizon gravelly loam, black (10YR 2/1) moist; weak very Hue: 7.5YR or 10YR fine and fine granular structure; soft, very friable, Value: 5 to 8 dry; 4 to 6 moist nonsticky, slightly plastic; common medium and Chroma: 2 to 4 many very fine and fine roots; many very fine and Texture (less than 2 mm): Loam or clay loam fine pores; 15 percent gravel; neutral (pH 7.2); Clay content: 18 to 35 percent abrupt smooth boundary. Content of rock fragments: 35 to 80 percent—5 to Bw—3 to 10 inches; grayish brown (10YR 5/2) 20 percent stones and cobbles; 30 to gravelly loam, very dark grayish brown (10YR 3/ 60 percent gravel 2) moist; weak fine and medium subangular Calcium carbonate equivalent: 5 to 15 percent blocky structure; soft, very friable, nonsticky, Reaction: pH 7.4 to 8.4 142 Soil Survey

Tibson Series fine roots; few very fine and fine pores; many fine and medium masses of lime; 30 percent gravel; Depth class: Very deep (greater than 60 inches) 15 percent cobbles; violently effervescent; Drainage class: Well drained moderately alkaline (pH 8.4). Permeability: Moderate (0.6 to 2.0 inches/hour) Range in Characteristics Landform: Landslide, moraine, and mountain Parent material: Gravelly till Soil temperature: 37 to 45 degrees F Slope range: 4 to 70 percent Moisture control section: Between 4 and 12 inches Elevation range: 6,000 to 7,500 feet Thickness of the mollic epipedon: 7 to 12 inches Mean annual precipitation: 20 to 25 inches Depth to the Bk horizon: 6 to 12 inches Mean annual air temperature: 36 to 38 degrees F Note: Some pedons have a Bw horizon. Frost-free period: 50 to 70 days A horizon Hue: 10YR Taxonomic Class: Loamy-skeletal, mixed, Value: 3 or 4 dry; 2 or 3 moist superactive Calcic Haplocryolls Chroma: 1 or 2 Texture (less than 2 mm): Loam Typical Pedon Clay content: 18 to 27 percent Tibson gravelly loam, in an area of Tibson, extremely Content of rock fragments: 15 to 60 percent—0 to bouldery-Bridger, extremely bouldery-Adel complex, 15 percent stones and cobbles; 15 to 8 to 35 percent slopes, extremely bouldery, in an area 45 percent gravel or channers of rangeland, 100 feet north and 1,600 feet east of Reaction: pH 7.4 to 7.8 the southwest corner of sec. 13, T. 3 S., R. 13 E.; Bk1 horizon USGS Squaw Peak topographic quadrangle (lat. Hue: 10YR or 2.5Y 45o34'06" N.; long. 110o04'03" W.) Value: 5 to 8 dry; 4 to 6 moist A—0 to 7 inches; dark grayish brown (10YR 4/2) Chroma: 2 to 4 or 6 gravelly loam, very dark gray (10YR 3/1) moist; Texture (less than 2 mm): Loam, clay loam, or weak fine granular structure; soft, very friable, sandy clay loam slightly sticky, slightly plastic; many very fine and Clay content: 18 to 30 percent fine roots; common very fine and fine pores; Content of rock fragments: 35 to 60 percent—0 to 15 percent gravel; 5 percent cobbles; slightly 25 percent stones and cobbles; 20 to alkaline (pH 7.6); abrupt wavy boundary. 50 percent gravel or channers Bk1—7 to 19 inches; pale brown (10YR 6/3) very Calcium carbonate equivalent: 20 to 35 percent gravelly loam, dark grayish brown (10YR 4/2) Reaction: pH 7.9 to 8.4 moist; weak fine subangular blocky structure; soft, Bk2 and Bk3 horizons friable, slightly sticky, slightly plastic; common fine Hue: 10YR or 2.5Y and many very fine roots; common very fine and Value: 5 to 8 dry; 4 to 6 moist fine pores; few fine and medium soft masses of Chroma: 2 to 4 lime; 25 percent gravel; 10 percent cobbles; Texture (less than 2 mm): Loam, clay loam, or violently effervescent; moderately alkaline sandy clay loam (pH 8.0); clear wavy boundary. Clay content: 18 to 30 percent Bk2—19 to 31 inches; very pale brown (10YR 7/3) Content of rock fragments: 35 to 60 percent—0 to very gravelly loam, brown (10YR 4/3) moist; weak 25 percent stones and cobbles; 20 to medium subangular blocky structure; soft, friable, 50 percent gravel or channers slightly sticky, slightly plastic; common very fine Calcium carbonate equivalent: 15 to 40 percent and fine roots; few very fine and fine pores; Reaction: pH 7.9 to 8.4 common fine and medium masses of lime; 25 percent gravel; 15 percent cobbles; violently effervescent; moderately alkaline (pH 8.2); clear Ticell Series wavy boundary. Bk3—31 to 60 inches; very pale brown (10YR 8/3) Depth class: Shallow (10 to 20 inches) very gravelly loam, pale brown (10YR 6/3) moist; Drainage class: Well drained weak coarse prismatic structure; soft, friable, Permeability: Moderate (0.6 to 2.0 inches/hour) slightly sticky, slightly plastic; few very fine and Landform: Hill and knoll on plain Sweet Grass County Area, Montana—Part I 143

Parent material: Residuum weathered from Range in Characteristics calcareous sandstone or sandstone and siltstone Soil temperature: 42 to 47 degrees F Slope range: 2 to 35 percent Moisture control section: Between 4 and 12 inches Elevation range: 4,200 to 6,200 feet Thickness of the mollic epipedon: 5 to 10 inches Mean annual precipitation: 15 to 20 inches Depth to bedrock: 10 to 20 inches Mean annual air temperature: 43 to 45 degrees F Frost-free period: 70 to 115 days A horizons Hue: 10YR or 2.5Y Taxonomic Class: Loamy, mixed, superactive, frigid Value: 5 dry; 2 or 3 moist Lithic Calciustolls Chroma: 2 or 3 Texture (less than 2 mm): Loam Typical Pedon Clay content: 10 to 22 percent Ticell loam, in an area of Ticell-Castner complex, 2 to Content of rock fragments: 0 to 20 percent—0 to 15 percent slopes, in an area of rangeland, 400 feet 5 percent cobbles; 0 to 15 percent gravel or south and 400 feet west of the northeast corner of channers sec. 21, T. 5 N., R. 15 E.; USGS Gougley Creek Calcium carbonate equivalent: 5 to 10 percent topographic quadrangle (lat. 46o10'28" N.; long. Reaction: pH 7.4 to 8.4 109o50'34" W.) Bk horizons A1—0 to 4 inches; grayish brown (2.5Y 5/2) loam, Hue: 10YR or 2.5Y dark olive brown (2.5Y 3/3) moist; weak fine and Value: 6 to 8 dry; 4 to 6 moist medium granular structure; slightly hard, very Chroma: 1 to 4 friable, slightly sticky, nonplastic; many very fine Texture (less than 2 mm): Silt loam or loam and fine roots; many very fine and fine pores; Clay content: 10 to 22 percent 3 percent cobbles; slightly effervescent; slightly Content of rock fragments: 0 to 15 percent gravel alkaline (pH 7.8); clear smooth boundary. or channers A2—4 to 8 inches; light olive brown (2.5Y 5/3) loam, Calcium carbonate equivalent: 15 to 30 percent dark olive brown (2.5Y 3/3) moist; weak fine and Reaction: pH 7.4 to 8.4 medium subangular blocky structure; slightly hard, very friable, slightly sticky, nonplastic; many very fine and fine roots; many very fine and fine Timberlin Series pores; 5 percent gravel; strongly effervescent; slightly alkaline (pH 7.8); abrupt wavy boundary. Depth class: Moderately deep (20 to 40 inches) Bk1—8 to 12 inches; pale yellow (2.5Y 8/2) silt loam, Drainage class: Well drained light brownish gray (2.5Y 6/2) moist; weak Permeability: Moderately slow (0.2 to 0.6 inch/hour) medium subangular blocky structure; moderately Landform: Mountain hard, very friable, slightly sticky, slightly plastic; Parent material: Loamy colluvium and/or residuum common fine and many very fine roots; common weathered from tuff breccia very fine and fine pores; common fine and Slope range: 8 to 60 percent medium masses of lime; 3 percent gravel; Elevation range: 5,500 to 7,500 feet violently effervescent; moderately alkaline Mean annual precipitation: 20 to 25 inches (pH 8.4); clear smooth boundary. Mean annual air temperature: 36 to 38 degrees F Bk2—12 to 17 inches; white (2.5Y 8/1) silt loam, light Frost-free period: 50 to 70 days brownish gray (2.5Y 6/2) moist; weak fine and medium platy structure parting to moderate Taxonomic Class: Loamy-skeletal, mixed, medium subangular blocky; very hard, friable, superactive Ustollic Haplocryalfs slightly sticky, slightly plastic; common very fine Typical Pedon and fine roots; common very fine and fine pores; many fine and medium masses of lime; Timberlin gravelly loam, in an area of Adel-Timberlin 10 percent gravel; violently effervescent; complex, 8 to 35 percent slopes, in an area of moderately alkaline (pH 8.4); abrupt wavy coniferous forest, 2,200 feet south and 2,500 feet boundary. east of the northwest corner of sec. 12, T. 3 S., R—17 inches; unweathered bedrock, calcareous R. 13 E.; USGS Squaw Peak topographic quadrangle sandstone. (lat. 45o35'27" N.; long. 110o03'50" W.) 144 Soil Survey

Oi—0 to 1 inch; slightly decomposed needles, twigs, A horizons and leaves. Hue: 10YR A1—1 to 3 inches; dark gray (10YR 4/1) gravelly Value: 4 or 5 dry; 2 or 3 moist loam, black, (10YR 2/1) moist; weak thin platy Chroma: 1 or 2 structure parting to weak fine granular; soft, very Texture (less than 2 mm): Loam friable, nonsticky, nonplastic; many fine and Clay content: 18 to 27 percent medium roots; many very fine and fine pores; Content of rock fragments: 5 to 35 percent—0 to 20 percent gravel; slightly acid (pH 6.2); abrupt 20 percent stones and cobbles; 5 to smooth boundary. 20 percent gravel or channers A2—3 to 6 inches; dark grayish brown (10YR 4/2) Reaction: pH 6.1 to 7.3 gravelly loam, black (10YR 2/1) moist; weak thin E horizon: platy structure parting to weak fine and medium Hue: 10YR or 2.5Y subangular blocky; soft, very friable, nonsticky, Value: 5 or 6 dry; 4 or 5 moist nonplastic; many fine and medium roots; many Chroma: 1 or 2 very fine and fine pores; 25 percent gravel; Texture (less than 2 mm): Loam slightly acid (pH 6.2); clear smooth boundary. Clay content: 18 to 27 percent E—6 to 12 inches; grayish brown (10YR 5/2) gravelly Content of rock fragments: 15 to 40 percent—0 to loam, dark gray (10YR 4/1) moist; weak medium 20 percent stones and cobbles; 15 to platy structure parting to weak medium 30 percent gravel or channers subangular blocky; soft, very friable, slightly Reaction: pH 6.1 to 7.3 sticky, slightly plastic; few coarse and many fine and medium roots; many very fine and fine pores; Bt1 horizon 30 percent gravel; slightly acid (pH 6.2); gradual Hue: 10YR or 2.5Y smooth boundary. Value: 5 or 6 dry; 4 or 5 moist Bt1—12 to 22 inches; brown (10YR 5/3) very gravelly Chroma: 3 or 4 loam, brown (10YR 4/3) moist; moderate fine and Texture (less than 2 mm): Loam, sandy clay loam, medium subangular blocky structure; slightly or clay loam hard, friable, moderately sticky, moderately Clay content: 25 to 35 percent plastic; many fine and medium roots; many very Content of rock fragments: 35 to 60 percent— fine and fine pores; common distinct 10 to 30 percent stones and cobbles; 30 to discontinuous dark brown (7.5YR 3/4) moist; 45 percent gravel or channers clay films on faces of peds and lining pores; Reaction: pH 6.1 to 7.3 40 percent gravel; 5 percent cobbles; neutral Bt2 horizon (pH 6.6); clear smooth boundary. Hue: 10YR or 2.5Y Bt2—22 to 33 inches; brown (10YR 5/3) very gravelly Value: 5 or 6 dry; 4 or 5 moist loam, brown (10YR 4/3) moist; moderate fine and Chroma: 3 or 4 medium subangular blocky structure; slightly Texture (less than 2 mm): Loam, sandy clay loam, hard, friable, moderately sticky, moderately or clay loam plastic; few coarse and common fine and medium Clay content: 25 to 35 percent roots; many very fine and fine pores; common Content of rock fragments: 35 to 70 percent— distinct discontinuous dark brown (7.5YR 3/4) 10 to 30 percent stones and cobbles; 30 to moist; clay films on faces of peds and lining 45 percent gravel or channers pores; 45 percent gravel; 10 percent cobbles; Reaction: pH 6.1 to 7.3 coarse fragments increasing with depth; neutral (pH 6.8); abrupt smooth boundary. R—33 to 61 inches; unweathered bedrock; hard Tongue River Series sandstone and gabbro. Depth class: Moderately deep (20 to 40 inches) Range in Characteristics Drainage class: Well drained Permeability: Moderate (0.6 to 2.0 inches/hour) Soil temperature: 36 to 40 degrees F Landform: Mountain Moisture control section: Between 4 and 12 inches Parent material: Loamy colluvium and/or residuum Depth to bedrock: 20 to 40 inches weathered from sandstone and siltstone Note: Some pedons do not have an E horizon. Slope range: 15 to 60 percent Sweet Grass County Area, Montana—Part I 145

Elevation range: 5,500 to 7,500 feet E horizon Mean annual precipitation: 20 to 25 inches Hue: 7.5YR, 10YR, or 2.5Y Mean annual air temperature: 36 to 38 degrees F Value: 5 to 7 dry; 4 to 6 moist Frost-free period: 50 to 70 days Chroma: 2 to 4 Texture (less than 2 mm): Loam Taxonomic Class: Fine-loamy, mixed, superactive Clay content: 15 to 25 percent Eutric Haplocryalfs Content of rock fragments: 0 to 15 percent gravel Reaction: pH 5.6 to 7.3 Typical Pedon Bt horizons Hue: 10YR, 2.5Y, or 5Y Tongue River loam, in an area of Tongue River- Value: 5 to 7 dry; 4 or 5 moist Cabba, moist-Adel complex, 15 to 60 percent slopes, Chroma: 2 to 4 or 6 in an area of coniferous forest, 400 feet north and Texture (less than 2 mm): Clay loam, loam, or 100 feet west of the southeast corner of sec. 16, sandy clay loam T. 2 N., R. 12 E.; USGS Raspberry Butte topographic Clay content: 25 to 35 percent quadrangle (lat. 45o54'56" N.; long. 110o13'52" W.) Content of rock fragments: 0 to 25 percent gravel Oi—0 to 2 inches; slightly decomposed twigs, leaves or channers; 10 to 50 percent soft shale chips and needles; clear smooth boundary. Reaction: pH 5.6 to 7.3 E—2 to 10 inches; light brownish gray (10YR 6/2) loam, dark grayish brown (10YR 4/2) moist; weak medium subangular blocky structure parting to Turner Series strong fine granular; soft, very friable, slightly Depth class: Very deep (greater than 60 inches) sticky, slightly plastic; few fine to coarse and Drainage class: Well drained common very fine roots; common very fine and Permeability: In the upper 0 to 20 inches = moderate fine pores; 10 percent gravel; neutral (pH 7.0); (0.6 to 2.0 inches/hour); below this depth = rapid clear smooth boundary. (6 to 20 inches/hour) Bt1—10 to 22 inches; pale brown (10YR 6/3) clay Landform: Fan, stream terrace, and terrace loam, grayish brown (10YR 5/2) moist; moderate Parent material: Loamy over sandy and gravelly medium subangular blocky structure; slightly alluvium hard, friable, moderately sticky, moderately Slope range: 0 to 8 percent plastic; few fine to coarse and common very fine Elevation range: 4,200 to 6,000 feet roots; common very fine pores; common faint Mean annual precipitation: 15 to 19 inches discontinuous brown (10YR 4/3) moist; clay films Mean annual air temperature: 43 to 45 degrees F on faces of peds; 10 percent gravel; neutral Frost-free period: 85 to 115 days (pH 7.0); clear wavy boundary. Bt2—22 to 35 inches; pale brown (10YR 6/3) loam, Taxonomic Class: Fine-loamy over sandy or sandy- grayish brown (10YR 5/2) moist; weak medium skeletal, mixed, superactive, frigid Typic subangular blocky structure; slightly hard, friable, Argiustolls moderately sticky, moderately plastic; few very fine and fine roots; common very fine pores; Typical Pedon common faint discontinuous brown (10YR 4/3) Turner sandy clay loam, in an area of Roy-Turner moist; clay films on faces of peds; 40 to complex, 0 to 4 percent slopes, in an area of 50 percent soft shale chips; 10 percent gravel; rangeland, 700 feet north and 1,800 feet east of the neutral (pH 6.8); clear wavy boundary. southwest corner of sec. 26, T. 1 N., R. 14 E.; USGS Cr—35 to 62 inches; soft, gray calcareous shale; Big Timber topographic quadrangle (lat. 45o48'05" N.; strongly effervescent. long. 109o57'08" W.) Range in Characteristics A—0 to 5 inches; dark grayish brown (10YR 4/2) sandy clay loam, very dark grayish brown (10YR Soil temperature: 34 to 40 degrees F 3/2) moist; weak fine granular structure; soft, Moisture control section: Between 4 and 12 inches friable, slightly sticky, slightly plastic; common Depth to the Cr horizon: 20 to 40 inches very fine and fine roots; common fine pores; Note: Some pedons have a thin A horizon, and some 10 percent gravel; 3 percent cobbles; neutral pedons have a BC horizon. (pH 6.8); abrupt smooth boundary. 146 Soil Survey

Bt1—5 to 11 inches; brown (10YR 4/3) clay loam, A horizon dark brown (10YR 3/3) moist; weak medium Hue: 7.5YR, 10YR, or 2.5Y prismatic structure parting to moderate fine and Value: 4 or 5 dry; 2 or 3 moist medium subangular blocky; moderately hard, Chroma: 2 or 3 friable, moderately sticky, moderately plastic; Texture (less than 2 mm): Sandy loam, sandy common very fine and fine roots; common fine clay loam, or loam and medium pores; common prominent Clay content: 15 to 30 percent discontinuous dark reddish brown (5YR 3/3) Content of rock fragments: 0 to 35 percent—0 to moist; clay films on faces of peds; 5 percent 3 percent stones; 0 to 10 percent cobbles; 0 to gravel; neutral (pH 7.2); clear smooth boundary. 25 percent gravel Bt2—11 to 17 inches; brown (10YR 5/3) sandy clay Reaction: pH 6.1 to 7.8 loam, brown (10YR 4/3) moist; weak medium Bt horizons prismatic structure parting to moderate medium Hue: 7.5YR, 10YR, or 2.5Y subangular blocky; moderately hard, friable, Value: 4 to 6 dry; 3 to 5 moist moderately sticky, moderately plastic; common Chroma: 2 or 3 very fine and fine roots; common fine and Texture (less than 2 mm): Clay loam, loam, or medium pores; common prominent discontinuous sandy clay loam dark reddish brown (5YR 3/3), moist; clay films on Clay content: 25 to 35 percent faces of peds; 5 percent gravel; slightly alkaline Content of rock fragments: 0 to 30 percent—0 to (pH 7.6); clear smooth boundary. 5 percent cobbles; 0 to 25 percent gravel Bk1—17 to 26 inches; light gray (2.5Y 7/2) fine sandy Calcium carbonate equivalent: 0 to 15 percent loam, grayish brown (2.5Y 5/2) moist; weak Reaction: pH 6.6 to 8.4 coarse prismatic structure; slightly hard, friable, slightly sticky, slightly plastic; few fine roots; Bk horizon common fine pores; common fine threads and Hue: 7.5YR, 10YR, or 2.5Y soft masses of lime; 10 percent gravel; 4 percent Value: 5 to 7 dry; 4 to 6 moist cobbles; strongly effervescent; moderately Chroma: 2 to 4 alkaline (pH 8.4); abrupt smooth boundary. Texture (less than 2 mm): Fine sandy loam, loam, 2Bk2—26 to 51 inches; pale brown (10YR 6/3) very or clay loam gravelly loamy sand, brown (10YR 5/3) moist; Clay content: 18 to 35 percent single grain; loose, nonsticky, nonplastic; few fine Content of rock fragments: 0 to 30 percent—0 to roots; common distinct carbonate coats on 5 percent cobbles; 0 to 25 percent gravel undersides of rock fragments; 35 percent gravel; Calcium carbonate equivalent: 8 to 15 percent 15 percent cobbles; slightly effervescent; Reaction: pH 7.4 to 8.4 moderately alkaline (pH 8.4); gradual smooth 2Bk horizons boundary. Hue: 10YR or 2.5Y 2Bk3—51 to 60 inches; pale brown (10YR 6/3) Value: 5 to 7 dry; 4 to 6 moist extremely gravelly coarse sand, brown (10YR Chroma: 2 to 4 5/3) moist; single grain; loose, nonsticky, Texture (less than 2 mm): Loamy sand, sand, or nonplastic; 40 percent gravel; 20 percent cobbles; coarse sand 10 percent stones; few carbonate coats on Clay content: 0 to 5 percent undersides of rock fragments; slightly Content of rock fragments: 35 to 80 percent—5 to effervescent; moderately alkaline (pH 8.4). 30 percent stones and cobbles; 30 to Range in Characteristics 60 percent gravel Calcium carbonate equivalent: 2 to 12 percent Soil temperature: 41 to 47 degrees F Reaction: pH 7.4 to 8.4 Moisture control section: Between 4 and 12 inches Thickness of the mollic epipedon: 7 to 15 inches 2C horizon Depth to the Bk horizon: 11 to 20 inches Hue: 10YR or 2.5Y Depth to the 2Bk horizon: 20 to 35 inches Value: 5 to 7 dry; 4 to 6 moist Depth to the seasonal high water table (seeped Chroma: 2 to 4 phase): 0 to 12 inches Texture (less than 2 mm): Sand or coarse sand Note: Some pedons do not have a 2C horizon. Clay content: 0 to 5 percent Sweet Grass County Area, Montana—Part I 147

Content of rock fragments: 35 to 80 percent—5 to structure; slightly hard, friable, nonsticky, 20 percent stones and cobbles; 30 to nonplastic; few fine and medium roots; few very 60 percent gravel fine and fine pores; few fine threads and soft Calcium carbonate equivalent: 2 to 12 percent masses of lime; 10 percent gravel; strongly Reaction: pH 7.4 to 8.4 effervescent; slightly alkaline (pH 7.8); abrupt smooth boundary. Cr—26 inches; light yellowish brown (2.5Y 6/3) Twilight Series semiconsolidated sandstone. Depth class: Moderately deep (20 to 40 inches) Range in Characteristics Drainage class: Well drained Soil temperature: 42 to 47 degrees F Permeability: Moderately rapid (2 to 6 inches/hour) Moisture control section: Between 8 and 24 inches Landform: Escarpment, hill, and swale on plain Depth to the Bk horizon: 10 to 20 inches Parent material: Sandy residuum weathered from Depth to the Cr horizon: 20 to 40 inches calcareous sandstone Slope range: 2 to 25 percent A horizon Elevation range: 3,750 to 5,200 feet Hue: 10YR or 2.5Y Mean annual precipitation: 10 to 14 inches Value: 4 or 5 dry; 3 or 4 moist Mean annual air temperature: 43 to 46 degrees F Chroma: 2 or 3 Frost-free period: 95 to 125 days Texture (less than 2 mm): Fine sandy loam Clay content: 5 to 18 percent Taxonomic Class: Coarse-loamy, mixed, Content of rock fragments: 0 to 5 percent gravel superactive, frigid Haplocalcidic Haplustepts Reaction: pH 6.6 to 7.8 Bw horizons Typical Pedon Hue: 10YR or 2.5Y Value: 5 or 6 dry; 4 or 5 moist Twilight fine sandy loam, in an area of Chinook- Chroma: 2 to 4 Twilight fine sandy loams, 8 to 25 percent slopes, in Texture (less than 2 mm): Fine sandy loam or an area of rangeland, 700 feet north and 750 feet sandy loam east of the southwest corner of sec. 4, T. 5 N., Clay content: 5 to 18 percent R. 15 E.; USGS Gougley Creek topographic Content of rock fragments: 0 to 5 percent gravel quadrangle (lat. 46o12'26" N.; long. 109o51'32" W.) Reaction: pH 6.6 to 7.8 A—0 to 6 inches; grayish brown (10YR 5/2) fine Bk horizon sandy loam, dark grayish brown (10YR 4/2) Hue: 10YR or 2.5Y moist; weak fine granular structure; soft, friable, Value: 5 to 7 dry; 4 to 6 moist nonsticky, nonplastic; many very fine and fine Chroma: 2 to 4 roots; many very fine and fine pores; 5 percent Texture (less than 2 mm): Fine sandy loam, gravel; neutral (pH 6.8); clear smooth boundary. loamy sand, or sandy loam Bw1—6 to 13 inches; brown (10YR 5/3) fine sandy Clay content: 5 to 18 percent loam, dark grayish brown (10YR 4/2) moist; weak Content of rock fragments: 0 to 10 percent gravel medium prismatic structure parting to weak Calcium carbonate equivalent: 5 to 10 percent coarse subangular blocky; soft, very friable, Electrical conductivity: 0 to 4 mmhos/cm nonsticky, nonplastic; common very fine and fine Reaction: pH 7.4 to 8.4 roots; common very fine and fine pores; neutral (pH 7.0); clear smooth boundary. Bw2—13 to 20 inches; yellowish brown (10YR 5/4) Vebar Series fine sandy loam, brown (10YR 4/3) moist; weak fine and medium subangular blocky structure; Depth class: Moderately deep (20 to 40 inches) soft, very friable, nonsticky, nonplastic; few very Drainage class: Well drained fine and fine roots; common very fine and fine Permeability: Moderately rapid (2 to 6 inches/hour) pores; neutral (pH 7.2); clear smooth boundary. Landform: Swale on plain Bk—20 to 26 inches; pale brown (10YR 6/3) loamy Parent material: Coarse-loamy alluvium over sand, dark yellowish brown (10YR 4/4) moist; residuum weathered from calcareous sandstone weak fine and medium subangular blocky Slope range: 2 to 8 percent 148 Soil Survey

Elevation range: 5,300 to 6,200 feet Cr—38 to 42 inches; light brownish gray (2.5Y 6/2) Mean annual precipitation: 17 to 20 inches sandstone, dark grayish brown (2.5Y 4/2) moist; Mean annual air temperature: 39 to 42 degrees F violently effervescent. Frost-free period: 70 to 90 days Range in Characteristics Taxonomic Class: Coarse-loamy, mixed, Soil temperature: 40 to 47 degrees F superactive, frigid Typic Haplustolls Moisture control section: Between 8 and 24 inches Thickness of the mollic epipedon: 7 to 16 inches Typical Pedon Depth to the Bk horizon: 11 to 36 inches Vebar fine sandy loam, in an area of Vebar-Castner Depth to the Cr horizon: 20 to 40 inches complex, 2 to 8 percent slopes, in an area of A horizon rangeland, 1,600 feet north and 600 feet east of Hue: 10YR the southwest corner of sec. 23, T. 5 N., R. 14 E.; Value: 3 to 5 dry; 2 or 3 moist USGS Melville NW topographic quadrangle Chroma: 2 or 3 (lat. 46o10'01" N.; long. 109o56'37" W.) Texture (less than 2 mm): Fine sandy loam, loam, A—0 to 5 inches; dark grayish brown (10YR 4/2) fine or sandy loam sandy loam, very dark brown (10YR 2/2) moist; Clay content: 10 to 18 percent moderate very fine granular structure; soft, very Content of rock fragments: 0 to 15 percent gravel friable, nonsticky, nonplastic; few medium and or channers coarse and many very fine and fine roots; many Reaction: pH 6.1 to 7.8 very fine and fine pores; neutral (pH 7.2); clear Bw horizons wavy boundary. Hue: 10YR or 2.5Y Bw1—5 to 12 inches; brown (10YR 4/3) fine sandy Value: 4 to 6 dry; 3 or 4 moist loam, dark brown (10YR 3/3) moist; weak fine Chroma: 2 to 4 and medium subangular blocky structure parting Texture (less than 2 mm): Fine sandy loam to moderate very fine and fine granular; soft, very Clay content: 10 to 18 percent friable, nonsticky, nonplastic; common fine and Content of rock fragments: 0 to 15 percent gravel medium and many very fine roots; many very fine or channers and fine pores; neutral (pH 7.2); clear wavy Reaction: pH 6.1 to 8.4 boundary. Bw2—12 to 22 inches; brown (10YR 5/3) fine sandy Bk horizons loam, brown (10YR 4/3) moist; weak coarse Hue: 10YR, 2.5Y, or 5Y subangular blocky structure; soft, very friable, Value: 5 to 7 dry; 4 to 6 moist nonsticky, nonplastic; common very fine and fine Chroma: 2 to 4 roots; many very fine and fine pores; neutral Texture (less than 2 mm): Fine sandy loam or (pH 7.2); gradual wavy boundary. sandy loam Bk1—22 to 28 inches; light brownish gray (10YR 6/2) Clay content: 5 to 18 percent fine sandy loam, brown (10YR 5/3) moist; weak Content of rock fragments: 0 to 20 percent gravel coarse subangular blocky structure; soft, very or channers friable, nonsticky, nonplastic; few fine and Calcium carbonate equivalent: 5 to 15 percent common very fine roots; many very fine and fine Reaction: pH 6.6 to 8.4 pores; few fine and medium irregular soft masses of lime; strongly effervescent; moderately alkaline (pH 8.2); clear wavy boundary. Vershal Series Bk2—28 to 38 inches; light brownish gray (2.5Y 6/2) gravelly fine sandy loam, light olive brown (2.5Y Depth class: Very shallow (0 to 10 inches) 5/3) moist; weak coarse subangular blocky Drainage class: Well drained structure; soft, very friable, nonsticky, nonplastic; Permeability: Moderate (0.6 to 2.0 inches/hour) few very fine and fine roots; many very fine and Landform: Escarpment, hill, and knoll on plain fine pores; common fine and medium irregular Parent material: Residuum weathered from soft masses of lime; 20 percent gravel; violently sandstone effervescent; moderately alkaline (pH 8.4); clear Slope range: 2 to 60 percent wavy boundary. Elevation range: 3,900 to 6,000 feet Sweet Grass County Area, Montana—Part I 149

Mean annual precipitation: 15 to 19 inches Landform: Fan, terrace, and fan on escarpment Mean annual air temperature: 43 to 45 degrees F Parent material: Clayey over gravelly alluvium Frost-free period: 85 to 115 days Slope range: 0 to 8 percent Elevation range: 3,750 to 5,200 feet Taxonomic Class: Loamy-skeletal, mixed, Mean annual precipitation: 10 to 14 inches superactive, frigid Lithic Haplustolls Mean annual air temperature: 43 to 46 degrees F Frost-free period: 95 to 125 days Typical Pedon Vershal very channery loam, 20 percent slopes, in an Taxonomic Class: Clayey over loamy-skeletal, area of rangeland, 1,300 feet south and 1,900 feet smectitic over mixed, superactive, frigid Aridic west of the northeast corner of sec. 15, T. 5 N., Argiustolls R. 8 E.; Meagher County, Montana. Typical Pedon A1—0 to 4 inches; brown (10YR 5/3) very channery loam, dark brown (10YR 3/3) moist; weak very Verson loam, in an area of Verson loam, 0 to fine granular structure; soft, very friable, slightly 4 percent slopes, in an area of rangeland, 1,500 feet sticky, slightly plastic; many very fine roots; south and 500 feet east of the northwest corner of 5 percent cobbles; 40 percent channers; neutral sec. 27, T. 3 N., R. 18 E.; USGS Russell Gulch (pH 6.8); clear smooth boundary. topographic quadrangle (lat. 45o59'07" N.; long. A2—4 to 8 inches; brown (7.5YR 5/2) extremely 109o28'58" W.) channery loam, dark brown (7.5YR 3/2) moist; moderate very fine granular structure; soft, very A—0 to 5 inches; dark grayish brown (10YR 5/2) friable, slightly sticky, nonplastic; many very fine loam, dark brown (10YR 3/2) moist; weak fine roots; 15 percent cobbles; 55 percent channers; granular structure; soft, friable, slightly sticky, neutral (pH 7.0). (The combined thickness of the slightly plastic; few fine and common very fine A horizons is 5 to 10 inches.) roots; common very fine and fine pores; 5 percent R—8 inches; hard sandstone bedrock with a few gravel; neutral (pH 7.2); abrupt smooth boundary. cracks; few fine roots in some cracks. Bt1—5 to 9 inches; brown (7.5YR 5/2) clay, dark brown (7.5YR 3/2) moist; moderate medium Range in Characteristics subangular blocky structure; moderately hard, Soil temperature: 42 to 47 degrees F firm, moderately sticky, moderately plastic; Moisture control section: Between 4 inches and common very fine roots; common very fine and bedrock fine pores; common distinct dark brown (10YR Thickness of the mollic epipedon: 4 to 9 inches 3/3) moist; clay films on faces of peds; 5 percent Depth to bedrock: 4 to 10 inches gravel; slightly alkaline (pH 7.4); clear smooth Note: Some pedons have a Bw horizon. boundary. Bt2—9 to 13 inches; brown (7.5YR 5/2) clay loam, A horizons dark brown (7.5YR 4/2) moist; weak medium Hue: 7.5YR or 10YR subangular blocky structure parting to moderate Value: 4 or 5 dry; 2 or 3 moist fine subangular blocky; moderately hard, firm, Chroma: 2 or 3 moderately sticky, moderately plastic; common Texture (less than 2 mm): Loam very fine roots; common very fine and fine pores; Clay content: 18 to 27 percent common distinct dark yellowish brown (10YR 3/4) Content of rock fragments: 35 to 60 percent—0 to moist; clay films on faces of peds; 10 percent 15 percent flagstones; 35 to 45 percent gravel; slightly alkaline (pH 7.4); clear smooth channers boundary. Reaction: pH 5.6 to 7.3 Bt3—13 to 21 inches; brown (10YR 5/3) gravelly clay loam, dark grayish brown (10YR 4/2) moist; weak Verson Series medium prismatic structure; moderately hard, firm, slightly sticky, slightly plastic; few very fine Depth class: Very deep (greater than 60 inches) roots; few very fine and fine pores; common faint Drainage class: Well drained dark yellowish brown (10YR 4/4) moist; clay films Permeability: In the upper 0 to 22 inches = slow lining pores; 10 percent gravel; 5 percent (0.06 to 0.20 inch/hour); below this depth = channers; slightly alkaline (pH 7.6); gradual moderately rapid (2 to 6 inches/hour) smooth boundary. 150 Soil Survey

2Bk—21 to 60 inches; light brownish gray (10YR 6/2) Vision Series very gravelly loam, grayish brown (10YR 5/2) moist; weak medium prismatic structure; soft, Depth class: Very deep (greater than 60 inches) friable, slightly sticky, slightly plastic; few fine Drainage class: Well drained roots; discontinuous carbonate coats on Permeability: Moderate (0.6 to 2.0 inches/hour) undersides of rock fragments; few fine soft Landform: Hill masses of lime; 40 percent gravel; 10 percent Parent material: Gravelly colluvium weathered from cobbles; strongly effervescent; moderately tuff breccia alkaline (pH 8.0). Slope range: 35 to 60 percent Elevation range: 3,900 to 6,000 feet Range in Characteristics Mean annual precipitation: 15 to 19 inches Soil temperature: 43 to 47 degrees F Mean annual air temperature: 43 to 45 degrees F Moisture control section: Between 4 and 12 inches Frost-free period: 85 to 115 days Thickness of the mollic epipedon: 7 to 12 inches Depth to the Bk horizon (where present): 11 to Taxonomic Class: Loamy-skeletal, mixed, 21 inches superactive, frigid Typic Haplustalfs Depth to the 2Bk horizon: 15 to 36 inches Note: Some pedons have a Bk horizon. Typical Pedon A horizon Vision gravelly loam, in an area of Vision-Sweetweed- Hue: 10YR or 2.5Y Whitlash complex, 25 to 60 percent slopes, in an area Value: 5 dry; 2 or 3 moist of coniferous forest, 2,400 feet south and 250 feet Chroma: 2 or 3 east of the northwest corner of sec. 19, T. 2 S., Texture (less than 2 mm): Loam or clay loam R. 16 E.; USGS Packsaddle Butte topographic Clay content: 20 to 35 percent quadrangle (lat. 45o38'46" N.; long. 109o48'28" W.) Content of rock fragments: 0 to 15 percent—0 to 5 percent cobbles; 0 to 10 percent gravel or Oi—0 to 1 inch; slightly decomposed needles, twigs, channers and leaves. Reaction: pH 6.1 to 7.3 A1—1 to 4 inches; dark grayish brown (10YR 4/2) gravelly loam, very dark brown (10YR 2/2) moist; Bt horizons weak thin platy structure parting to weak fine Hue: 7.5YR, 10YR, or 2.5Y granular; soft, very friable, slightly sticky, slightly Value: 4 or 5 dry; 3 or 4 moist plastic; many very fine and fine roots; many very Chroma: 2 to 4 fine and fine pores; 13 percent gravel; 5 percent Texture (less than 2 mm): Clay loam, silty clay, cobbles; slightly acid (pH 6.4); abrupt smooth clay, or silty clay loam boundary. Clay content: 35 to 55 percent A2—4 to 8 inches; dark grayish brown (10YR 4/2) Content of rock fragments: 0 to 15 percent—0 to gravelly loam, very dark brown (10YR 2/2) moist; 5 percent cobbles; 0 to 15 percent gravel or weak medium subangular blocky structure; soft, channers very friable, slightly sticky, slightly plastic; Reaction: pH 6.1 to 7.8 common medium and many fine roots; many very 2Bk horizon fine and fine pores; 20 percent gravel; 5 percent Hue: 10YR or 2.5Y cobbles; slightly acid (pH 6.4); clear wavy Value: 5 to 7 dry; 4 or 5 moist boundary. Chroma: 2 to 4 Bt1—8 to 13 inches; grayish brown (10YR 5/2) Texture (less than 2 mm): Loam or sandy loam gravelly loam, dark grayish brown (10YR 4/2) Clay content: 5 to 25 percent moist; weak medium subangular blocky structure; Content of rock fragments: 50 to 85 percent—5 to slightly hard, friable, slightly sticky, slightly plastic; 10 percent cobbles; 40 to 75 percent gravel common fine and medium roots; many very fine Calcium carbonate equivalent: 5 to 15 percent and fine pores; common faint discontinuous dark Reaction: pH 7.4 to 8.4 brown (10YR 3/3) moist; clay films on faces Sweet Grass County Area, Montana—Part I 151

of peds and lining pores; 25 percent gravel; Clay content: 20 to 35 percent 5 percent cobbles; slightly acid (pH 6.4); clear Content of rock fragments: 15 to 35 percent—5 to smooth boundary. 15 percent stones and cobbles; 10 to Bt2—13 to 21 inches; brown (10YR 5/3) very gravelly 25 percent gravel or channers clay loam, brown (10YR 4/3) moist; moderate Reaction: pH 5.6 to 7.3 medium subangular blocky structure; slightly Bt2 and Bt3 horizons hard, friable, moderately sticky, moderately Hue: 10YR or 2.5Y plastic; common fine and medium roots; many Value: 5 to 7 dry; 4 or 5 moist very fine and fine pores; common distinct Chroma: 2 to 4 discontinuous dark yellowish brown (10YR 4/4) Texture (less than 2 mm): Clay loam, loam, or moist; clay films on faces of peds and lining sandy clay loam pores; 35 percent gravel; 5 percent cobbles; Clay content: 25 to 35 percent slightly acid (pH 6.4); clear smooth boundary. Content of rock fragments: 35 to 60 percent—5 to Bt3—21 to 37 inches; very pale brown (10YR 7/3) 30 percent stones and cobbles; 30 to very gravelly clay loam, brown (10YR 5/3) moist; 50 percent gravel or channers moderate medium and coarse subangular blocky Reaction: pH 5.6 to 7.3 structure; slightly hard, friable, moderately sticky, moderately plastic; few coarse and common fine BC horizon and medium roots; many very fine and fine pores; Hue: 10YR or 2.5Y common distinct discontinuous dark yellowish Value: 5 to 7 dry; 4 or 5 moist brown and yellowish brown (10YR 4/4 and 5/4) Chroma: 2 to 4 moist; clay films on faces of peds and lining Texture (less than 2 mm): Loam or sandy loam pores; 40 percent gravel; 10 percent cobbles; Clay content: 10 to 27 percent slightly acid (pH 6.4); clear wavy boundary. Content of rock fragments: 35 to 80 percent— BC—37 to 61 inches; very pale brown (10YR 7/3) 15 to 30 percent stones and cobbles; 20 to extremely gravelly loam, yellowish brown (10YR 50 percent gravel or channers 5/4) moist; weak fine and medium subangular Reaction: pH 5.6 to 7.3 blocky structure; soft, very friable, slightly sticky, slightly plastic; few coarse and common medium roots; many very fine and fine pores; common Warwood Series distinct dark yellowish brown (10YR 4/4) moist, stains on coarse fragments; 45 percent gravel; Depth class: Very deep (greater than 60 inches) 15 percent cobbles; 5 percent stones; neutral Drainage class: Well drained (pH 6.6). Permeability: Moderate (0.6 to 2.0 inches/hour) Landform: Mountain Range in Characteristics Parent material: Loamy alluvium or colluvium Soil temperature: 40 to 45 degrees F Slope range: 4 to 45 percent Moisture control section: Between 4 and 12 inches Elevation range: 5,500 to 7,500 feet Mean annual precipitation: 20 to 25 inches A horizons Mean annual air temperature: 36 to 38 degrees F Hue: 10YR Frost-free period: 50 to 70 days Value: 4 or 5 dry; 2 or 3 moist Chroma: 1 to 3 Taxonomic Class: Fine-loamy, mixed, superactive Texture (less than 2 mm): Loam Eutric Glossocryalfs Clay content: 10 to 20 percent Content of rock fragments: 15 to 35 percent—5 to Typical Pedon 15 percent stones and cobbles; 10 to 25 percent gravel or channers Warwood loam, in an area of Warwood-Timberlin- Reaction: pH 5.6 to 7.3 Cowood complex, 8 to 35 percent slopes, in an area of coniferous forest, 600 feet south and 2,300 feet Bt1 horizon west of the northeast corner of sec. 12, T. 3 S., Hue: 10YR or 2.5Y R. 13 E.; USGS Squaw Peak topographic quadrangle Value: 5 or 6 dry; 4 or 5 moist (lat. 45o35'42" N.; long. 110o03'44" W.) Chroma: 2 or 3 Texture (less than 2 mm): Loam, sandy clay loam, Oi—0 to 2 inches; forest litter of partially decomposed or clay loam needles, twigs, and leaves. 152 Soil Survey

A—2 to 5 inches; grayish brown (10YR 5/2) loam, Range in Characteristics dark grayish brown (10YR 4/2) moist; weak thin Soil temperature: 40 to 44 degrees F platy structure parting to weak very fine and fine Moisture control section: Between 4 and 12 inches granular; soft, very friable, nonsticky, nonplastic; Depth to the Bt horizon: 4 to 24 inches many very fine and fine roots; many very fine and Note: Some pedons have an A horizon. Some pedons fine pores; 5 percent gravel; moderately acid do not have a BC horizon. (pH 5.6); clear smooth boundary. E—5 to 13 inches; light brownish gray (10YR 6/2) A horizon loam, brown (10YR 5/3) moist; weak thin platy Hue: 10YR or 2.5Y structure parting to weak fine and medium Value: 4 to 6 dry; 3 or 4 moist granular; soft, very friable, slightly sticky, slightly Chroma: 2 or 3 plastic; many very fine and fine roots; many very Texture (less than 2 mm): Loam fine and fine pores; 5 percent gravel; moderately Clay content: 20 to 27 percent acid (pH 6.0); clear smooth boundary. Content of rock fragments: 5 to 15 percent—0 to E/Bt—13 to 20 inches; E part (75 percent) light 5 percent cobbles; 5 to 10 percent gravel brownish gray (10YR 6/2) loam, brown (10YR Reaction: pH 5.6 to 6.5 5/3) moist tongues; Bt part (25 percent) brown E horizon (10YR 5/3) loam, brown (10YR 4/3) moist; weak Hue: 10YR or 2.5Y medium and moderate medium subangular Value: 5 or 6 dry; 3 to 5 moist blocky structure; slightly hard, very friable, slightly Chroma: 2 or 3 sticky, slightly plastic; many fine and medium Texture (less than 2 mm): Loam or sandy loam roots; many very fine and fine pores; faint patchy Clay content: 15 to 27 percent dark yellowish brown (10YR 4/4) moist; clay films Content of rock fragments: 5 to 15 percent—0 to on faces of peds in Bt part; 5 percent gravel; 5 percent cobbles; 5 to 15 percent gravel slightly acid (pH 6.2); gradual irregular boundary. Reaction: pH 5.6 to 6.5 Bt1—20 to 30 inches; brown (10YR 5/3) clay loam, brown (10YR 4/3) moist; moderate medium E/Bt horizon subangular blocky structure; slightly hard, friable, Hue: 10YR or 2.5Y moderately sticky, moderately plastic; common Value: E part—5 or 6, Bt part—4 or 5 dry; fine and medium roots; common very fine and E part—4 or 5, Bt part—3 or 4 moist fine pores; common distinct discontinuous dark Chroma: 2 or 3 yellowish brown (10YR 4/4) moist; clay films on Texture (less than 2 mm): Loam, sandy loam, or faces of peds and lining pores; 10 percent gravel; sandy clay loam slightly acid (pH 6.2); clear smooth boundary. Clay content: 15 to 30 percent Bt2—30 to 43 inches; pale brown (10YR 6/3) gravelly Content of rock fragments: 5 to 15 percent—0 to clay loam, brown (10YR 4/3) moist; moderate 5 percent cobbles; 5 to 15 percent gravel medium subangular blocky structure; slightly Reaction: pH 5.6 to 6.5 hard, friable, moderately sticky, slightly plastic; Bt1 horizon few coarse and common medium roots; common Hue: 10YR or 2.5Y very fine and fine pores; common distinct Value: 5 or 6 dry; 3 or 4 moist discontinuous yellowish brown (10YR 5/4) moist; Chroma: 2 or 3 clay films on faces of peds and lining pores; Texture (less than 2 mm): Clay loam or sandy 25 percent gravel; slightly acid (pH 6.2); gradual clay loam wavy boundary. Clay content: 27 to 35 percent BC—43 to 62 inches; light brownish gray (10YR 6/2) Content of rock fragments: 5 to 25 percent—0 to very gravelly sandy loam, grayish brown (10YR 5 percent cobbles; 5 to 20 percent gravel 5/2) moist; weak fine and medium subangular Reaction: pH 6.1 to 7.3 blocky structure parting to single grain; soft, very friable, nonsticky, nonplastic; few medium and Bt2 horizon coarse roots; many very fine and fine pores; Hue: 10YR or 2.5Y 40 percent gravel; slightly acid (pH 6.2). Value: 5 or 6 dry; 3 or 4 moist Sweet Grass County Area, Montana—Part I 153

Chroma: 2 or 3 fragments; strongly effervescent; moderately Texture (less than 2 mm): Clay loam or sandy alkaline (pH 8.0); clear smooth boundary. clay loam Cr1—14 to 20 inches; weathered shale with pockets Clay content: 27 to 35 percent of gypsum crystals between shale layers; strongly Content of rock fragments: 5 to 25 percent—0 to effervescent; moderately alkaline (pH 8.0); abrupt 5 percent cobbles; 5 to 20 percent gravel smooth boundary. Reaction: pH 6.1 to 7.3 Cr2—20 to 60 inches; calcareous shale. BC horizon: Range in Characteristics Hue: 10YR or 2.5Y Value: 5 or 6 dry; 4 or 5 moist Soil temperature: 40 to 44 degrees F Chroma: 2 or 3 Moisture control section: Between 4 and 12 inches Texture (less than 2 mm): Sandy loam or loam Depth to the Bk horizon: 4 to 10 inches Clay content: 10 to 27 percent Depth to the Cr horizon: 10 to 20 inches Content of rock fragments: 15 to 60 percent—0 to 10 percent cobbles; 15 to 50 percent gravel A horizon Reaction: pH 6.1 to 7.3 Hue: 2.5Y or 5Y Value: 5 to 7 dry; 3 to 5 moist Chroma: 2 or 3 Wayden Series Texture (less than 2 mm): Clay or clay loam Clay content: 27 to 50 percent Depth class: Shallow (10 to 20 inches) Content of rock fragments: 0 to 5 percent gravel Drainage class: Well drained or channers Permeability: Slow (0.06 to 0.20 inch/hour) Calcium carbonate equivalent: 0 to 5 percent Landform: Escarpment, fan, hill, terrace, and knoll on Electrical conductivity: 0 to 4 mmhos/cm plain Reaction: pH 7.4 to 8.4 Parent material: Clayey residuum weathered from shale and siltstone Bk horizon Slope range: 2 to 60 percent Hue: 2.5Y or 5Y Elevation range: 3,900 to 6,200 feet Value: 5 to 8 dry; 4 to 6 moist Mean annual precipitation: 15 to 20 inches Chroma: 1 to 4 Mean annual air temperature: 39 to 45 degrees F Texture (less than 2 mm): Clay, clay loam, or silty Frost-free period: 70 to 115 days clay Clay content: 35 to 50 percent Taxonomic Class: Clayey, smectitic, calcareous, Content of rock fragments: 0 to 15 percent gravel frigid, shallow Typic Ustorthents or channers; 0 to 50 percent soft shale chips Calcium carbonate equivalent: 5 to 10 percent Typical Pedon Electrical conductivity: 0 to 8 mmhos/cm Wayden clay loam, in an area of Wayden-Castner Reaction: pH 7.4 to 8.4 complex, 15 to 60 percent slopes, in an area of rangeland, 1,200 feet north and 2,400 feet west of the southeast corner of sec. 17, T. 4 S., R. 19 E.; Weedzunit Series Stillwater County, Montana. Depth class: Moderately deep (20 to 40 inches) A—0 to 6 inches; grayish brown (2.5Y 5/2) clay loam, Drainage class: Well drained dark grayish brown (2.5Y 4/2) moist; moderate Permeability: Moderately rapid (2 to 6 inches/hour) fine and medium granular structure; hard, firm, Landform: Hill moderately sticky, moderately plastic; many very Parent material: Residuum from tuff breccia fine and fine roots; many very fine and fine pores; Slope range: 8 to 35 percent slightly effervescent; slightly alkaline (pH 7.6); Elevation range: 3,900 to 6,200 feet gradual wavy boundary. Mean annual precipitation: 15 to 20 inches Bk—6 to 14 inches; light brownish gray (2.5Y 6/2) Mean annual air temperature: 39 to 45 degrees F clay loam, grayish brown (2.5Y 5/2) moist; Frost-free period: 70 to 115 days massive; hard, friable, moderately sticky, moderately plastic; many very fine and fine roots; Taxonomic Class: Coarse-loamy, mixed, about 2 percent clayey and sandy soft shale superactive, frigid Typic Haplustolls 154 Soil Survey

Typical Pedon A horizons Hue: 10YR or 2.5Y Weedzunit fine sandy loam, in an area of Weedzunit- Value: 4 or 5 dry; 2 or 3 moist Ashbon complex, 4 to 15 percent slopes, in an area Chroma: 2 or 3 of rangeland, 300 feet south and 1,100 feet west Texture (less than 2 mm): Fine sandy loam of the northeast corner of sec. 8, T. 2 S., R. 15 E.; Clay content: 10 to 18 percent USGS Ross Canyon topographic quadrangle Content of rock fragments: 0 to 15 percent gravel (lat. 45o40'49" N.; long. 109o53'44" W.) Reaction: pH 5.6 to 7.3 A1—0 to 7 inches; grayish brown (10YR 5/2) fine Bw1 horizon sandy loam, very dark grayish brown (10YR 3/2) Hue: 10YR or 2.5Y moist; weak fine granular structure; soft, very Value: 4 or 5 dry; 3 or 4 moist friable, slightly sticky, slightly plastic; many very Chroma: 2 or 3 fine and fine roots; many very fine and fine pores; Texture (less than 2 mm): Fine sandy loam or slightly acid (pH 6.2); clear smooth boundary. loam A2—7 to 11 inches; grayish brown (10YR 5/2) fine Clay content: 10 to 18 percent sandy loam, very dark grayish brown (10YR 3/2) Content of rock fragments: 0 to 15 percent gravel moist; weak medium subangular blocky structure Reaction: pH 5.6 to 7.3 parting to weak fine and medium granular; soft, very friable, slightly sticky, slightly plastic; many Bw2 horizon very fine and fine roots; many very fine and fine Hue: 10YR or 2.5Y pores; slightly acid (pH 6.2); clear smooth Value: 5 or 6 dry; 4 or 5 moist boundary. Chroma: 2 or 3 Bw1—11 to 17 inches; grayish brown (10YR 5/2) fine Texture (less than 2 mm): Fine sandy loam or sandy loam, brown (10YR 4/3) moist; weak loam medium subangular blocky structure; slightly Clay content: 10 to 18 percent hard, friable, slightly sticky, slightly plastic; many Content of rock fragments: 0 to 15 percent gravel very fine and fine roots; many very fine and fine Reaction: pH 5.6 to 7.3 pores; 5 percent gravel; slightly acid (pH 6.4); BC horizon clear smooth boundary. Hue: 10YR or 2.5Y Bw2—17 to 24 inches; brown (10YR 5/3) fine sandy Value: 5 or 6 dry; 4 or 5 moist loam, brown (10YR 4/3) moist; weak medium Chroma: 2 to 4 subangular blocky structure; slightly hard, friable, Texture (less than 2 mm): Fine sandy loam, slightly sticky, slightly plastic; common fine and sandy loam, or loam medium roots; many very fine and fine pores; Clay content: 10 to 18 percent 10 percent gravel; slightly acid (pH 6.4); gradual Content of rock fragments: 15 to 60 percent smooth boundary. gravel BC—24 to 29 inches; light brownish gray (10YR 6/2) Reaction: pH 5.6 to 7.3 gravelly fine sandy loam, grayish brown (10YR 5/2) moist; weak coarse prismatic structure; slightly hard, friable, nonsticky, nonplastic; few Whitlash Series fine and medium roots; many very fine and fine pores; 25 percent gravel; neutral (pH 6.6); abrupt Depth class: Shallow (10 to 20 inches) smooth boundary. Drainage class: Well drained R—29 to 33 inches; gray volcanic mudflow breccia. Permeability: Moderate (0.6 to 2.0 inches/hour) Landform: Hill, structural bench, and knoll on plain Range in Characteristics Parent material: Residuum weathered from gabbro or Soil temperature: 42 to 47 degrees F tuff breccia Moisture control section: Between 4 and 12 inches Slope range: 4 to 60 percent Thickness of the mollic epipedon: 7 to 15 inches Elevation range: 3,900 to 6,200 feet Depth to bedrock: 20 to 40 inches Mean annual precipitation: 15 to 20 inches Sweet Grass County Area, Montana—Part I 155

Mean annual air temperature: 39 to 45 degrees F Chroma: 2 or 3 Frost-free period: 70 to 115 days Texture (less than 2 mm): Loam, sandy clay loam, or sandy loam Taxonomic Class: Loamy-skeletal, mixed, Clay content: 10 to 27 percent superactive, frigid Lithic Haplustolls Content of rock fragments: 35 to 80 percent—5 to 50 percent stones, flagstones, or cobbles; 15 Typical Pedon to 60 percent gravel or channers Whitlash gravelly loam, in an area of Vision- Reaction: pH 6.1 to 7.3 Sweetweed-Whitlash complex, 25 to 60 percent slopes, in an area of coniferous forest, 1,200 feet south and 700 feet west of the northeast corner of Whitore Series sec. 9, T. 2 S., R. 15 E.; USGS Packsaddle Butte topographic quadrangle (lat. 45o40'41" N.; long. Depth class: Very deep (greater than 60 inches) 109o52'23" W.) Drainage class: Well drained Permeability: Moderate (0.6 to 2.0 inches/hour) Oi—0 to 1 inch; undecomposed needles, plant Landform: Moraine and mountain material, bark, twigs, and cones. Parent material: Gravelly colluvium weathered from A—1 to 8 inches; dark grayish brown (10YR 4/2) limestone and sandstone or gravelly till gravelly loam, very dark brown (10YR 2/2) moist; Slope range: 35 to 60 percent moderate fine and medium granular structure; Elevation range: 6,000 to 7,500 feet soft, friable, slightly sticky, slightly plastic; few Mean annual precipitation: 20 to 25 inches medium and many very fine and fine roots; Mean annual air temperature: 36 to 38 degrees F common very fine and fine pores; 20 percent Frost-free period: 50 to 70 days gravel; 10 percent cobbles; neutral (pH 7.0); clear smooth boundary. Taxonomic Class: Loamy-skeletal, carbonatic Typic Bw—8 to 16 inches; brown (10YR 5/3) very gravelly Eutrocryepts loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure parting to Typical Pedon moderate fine subangular blocky and weak fine Whitore loam, in an area of Tibson-Whitore-Rock granular; soft, friable, slightly sticky, slightly outcrop complex, 35 to 70 percent slopes, in an area plastic; common very fine and fine roots; common of coniferous forest, 320 feet north and 1,800 feet very fine and fine pores; 40 percent gravel; west of the southeast corner of sec. 24, T. 3 S., 15 percent cobbles; neutral (pH 6.8); abrupt R. 13 E.; USGS Squaw Peak topographic quadrangle smooth boundary. (lat. 45o33'32" N.; long. 110o03'17" W.) R—16 inches; hard, fine grained igneous rock. A—0 to 4 inches; grayish brown (10YR 5/2) loam, Range in Characteristics very dark grayish brown (10YR 3/2) moist; weak Soil temperature: 41 to 47 degrees F fine granular structure; soft, very friable, slightly Moisture control section: Between 4 and 12 inches sticky, slightly plastic; few medium and common Thickness of the mollic epipedon: 7 to 15 inches very fine and fine roots; many very fine and fine Depth to bedrock: 10 to 20 inches pores; 10 percent channers; strongly effervescent; slightly alkaline (pH 7.6); abrupt A horizon smooth boundary. Hue: 10YR or 2.5Y Bw—4 to 12 inches; brown (7.5YR 5/3) channery Value: 3 to 5 dry; 2 or 3 moist loam, brown (7.5YR 4/3) moist; weak fine and Chroma: 1 to 3 medium subangular blocky structure; soft, very Texture (less than 2 mm): Loam friable, slightly sticky, slightly plastic; common fine Clay content: 10 to 27 percent to coarse roots; many very fine and fine pores; Content of rock fragments: 15 to 60 percent—0 to 16 percent channers; strongly effervescent; 30 percent stones, flagstones, or cobbles; 15 moderately alkaline (pH 8.0); clear smooth to 35 percent gravel or channers boundary. Reaction: pH 6.1 to 7.3 Bk1—12 to 28 inches; light brown (7.5YR 6/3) very Bw horizon channery loam, brown (7.5YR 5/3) moist; weak Hue: 10YR or 2.5Y fine and medium subangular blocky structure; Value: 4 to 6 dry; 3 to 5 moist soft, very friable, slightly sticky, slightly plastic; 156 Soil Survey

common fine to coarse roots; many very fine and Chroma: 2 to 4 fine pores; common continuous carbonate coats Texture (less than 2 mm): Clay loam or loam on rock fragments; 40 percent channers; violently Clay content: 20 to 35 percent effervescent; moderately alkaline (pH 8.2); clear Content of rock fragments: 35 to 85 percent—0 to smooth boundary. 40 percent stones and cobbles; 25 to Bk2—28 to 42 inches; pinkish gray (7.5YR 7/2) very 65 percent gravel or channers channery loam, pinkish gray (7.5YR 6/2) moist; Calcium carbonate equivalent: 40 to 60 percent weak medium subangular blocky structure; soft, Reaction: pH 7.9 to 9.0 very friable, slightly sticky, slightly plastic; few fine to coarse roots; many very fine and fine pores; common continuous carbonate coats on rock Winifred Series fragments; 40 percent channers; 5 percent cobbles; violently effervescent; strongly alkaline Depth class: Moderately deep (20 to 40 inches) (pH 8.6); gradual smooth boundary. Drainage class: Well drained Bk3—42 to 60 inches; pinkish gray (7.5YR 7/2) very Permeability: Slow (0.06 to 0.20 inch/hour) channery loam, pinkish gray (7.5YR 6/2) moist; Landform: Escarpment, hill, and swale on plain weak medium subangular blocky structure; soft, Parent material: Clayey residuum weathered from very friable, slightly sticky, slightly plastic; few fine sandstone and shale and medium roots; common continuous Slope range: 2 to 45 percent carbonate coats on rock fragments; 45 percent Elevation range: 4,200 to 6,200 feet channers; 10 percent cobbles; violently Mean annual precipitation: 15 to 20 inches effervescent; strongly alkaline (pH 8.6). Mean annual air temperature: 39 to 45 degrees F Frost-free period: 70 to 115 days Range in Characteristics Soil temperature: 36 to 42 degrees F Taxonomic Class: Fine, smectitic, frigid Entic Moisture control section: Between 4 and 12 inches Haplustolls Depth to the Bk horizon: 5 to 15 inches Typical Pedon A horizon Winifred clay loam, in an area of Cabba-Winifred clay Hue: 7.5YR, 10YR, or 2.5Y loams, 2 to 8 percent slopes, in an area of rangeland, Value: 4 to 6 dry; 3 or 4 moist 500 feet north and 1,050 feet east of the southwest Chroma: 1 to 3 corner of sec. 16, T. 4 N., R. 14 E.; USGS Melville Texture (less than 2 mm): Loam topographic quadrangle (lat. 46o05'28" N.; long. Clay content: 18 to 27 percent 109o59'37" W.) Content of rock fragments: 5 to 60 percent—0 to 25 percent stones and cobbles; 5 to 35 percent A—0 to 4 inches; dark grayish brown (2.5Y 5/2) clay gravel or channers loam, very dark grayish brown (2.5Y 3/2) moist; Calcium carbonate equivalent: 0 to 15 percent moderate fine and medium granular structure; Reaction: pH 6.6 to 7.8 moderately hard, friable, moderately sticky, moderately plastic; many very fine and fine roots; Bw horizon many very fine and fine pores; slightly alkaline Hue: 7.5YR, 10YR, or 2.5Y (pH 7.6); abrupt smooth boundary. Value: 5 or 6 dry; 3 to 5 moist Bw—4 to 11 inches; grayish brown (2.5Y 5/2) clay, Chroma: 2 to 4 very dark grayish brown (2.5Y 3/2) moist; strong Texture (less than 2 mm): Loam or clay loam fine and medium subangular blocky structure; Clay content: 20 to 35 percent moderately hard, firm, very sticky, very plastic; Content of rock fragments: 15 to 60 percent—0 to many very fine and fine roots; many very fine and 25 percent stones and cobbles; 5 to 40 percent fine pores; strongly effervescent; moderately gravel or channers alkaline (pH 8.2); clear smooth boundary. Calcium carbonate equivalent: 35 to 50 percent Bk1—11 to 22 inches; grayish brown (2.5Y 5/2) clay, Electrical conductivity: 0 to 4 mmhos/cm dark grayish brown (2.5Y 4/2) moist; strong Reaction: pH 7.4 to 8.4 medium and coarse angular blocky structure; Bk horizons very hard, firm, very sticky, very plastic; common Hue: 7.5YR, 10YR, or 2.5Y very fine and fine roots; common very fine pores; Value: 6 to 8 dry; 4 to 7 moist common fine threads of lime; strongly Sweet Grass County Area, Montana—Part I 157

effervescent; moderately alkaline (pH 8.4); clear Clay content: 35 to 50 percent smooth boundary. Content of rock fragments: 0 to 15 percent gravel Bk2—22 to 30 inches; light brownish gray (2.5Y 6/2) or channers clay, grayish brown (2.5Y 5/2) moist; moderate Calcium carbonate equivalent: 5 to 15 percent coarse angular blocky structure; very hard, firm, Electrical conductivity: 0 to 4 mmhos/cm very sticky, very plastic; few fine and medium Sodium adsorption ratio: 1 to 5 roots; few very fine and fine pores; common fine Gypsum content: 1 to 5 percent and medium soft masses threads of lime; Reaction: pH 7.4 to 9.0 violently effervescent; strongly alkaline (pH 8.6); BC horizon: abrupt smooth boundary. Hue: 10YR or 2.5Y BC—30 to 35 inches; light gray (2.5Y 7/2) loam, light Value: 5 to 7 dry; 4 to 6 moist brownish gray (2.5Y 6/2) moist; weak coarse Chroma: 2 or 3 prismatic structure; soft, very friable, slightly Texture (less than 2 mm): Loam or clay loam sticky, slightly plastic; few fine and medium roots; Clay content: 20 to 40 percent 10 percent gravel; violently effervescent; strongly Content of rock fragments: 0 to 35 percent gravel alkaline (pH 8.8); clear smooth boundary. or channers Cr—35 to 60 inches; weathered bedrock; soft, Calcium carbonate equivalent: 5 to 15 percent calcareous siltstone; violently effervescent. Electrical conductivity: 0 to 4 mmhos/cm Range in Characteristics Sodium adsorption ratio: 1 to 5 Gypsum content: 1 to 5 percent Soil temperature: 42 to 47 degrees F Reaction: pH 7.4 to 9.0 Moisture control section: Between 4 and 12 inches Thickness of the mollic epipedon: 7 to 15 inches Depth to the Bk horizon: 11 to 22 inches Winkler Series Depth to the Cr horizon: 20 to 40 inches Note: Some pedons do not have a BC horizon. Depth class: Very deep (greater than 60 inches) Drainage class: Somewhat excessively drained A horizon Permeability: Moderately rapid (2 to 6 inches/hour) Hue: 10YR or 2.5Y Landform: Hill Value: 4 or 5 dry; 2 or 3 moist Parent material: Gravelly colluvium Chroma: 2 or 3 Slope range: 15 to 60 percent Texture (less than 2 mm): Clay loam Elevation range: 3,900 to 6,200 feet Clay content: 27 to 40 percent Mean annual precipitation: 15 to 20 inches Content of rock fragments: 0 to 35 percent—0 to Mean annual air temperature: 39 to 45 degrees F 20 percent cobbles; 0 to 15 percent gravel Frost-free period: 70 to 115 days Reaction: pH 6.6 to 7.8 Bw horizon Taxonomic Class: Loamy-skeletal, mixed, Hue: 10YR or 2.5Y superactive, frigid Lamellic Haplustepts Value: 4 or 5 dry; 3 or 4 moist Typical Pedon Chroma: 2 or 3 Texture (less than 2 mm): Clay loam, clay, or silty Winkler very gravelly sandy loam, in an area of clay Ashbon-Winkler-Rock outcrop complex, 35 to Clay content: 35 to 50 percent 60 percent slopes, in an area of coniferous forest, Content of rock fragments: 0 to 15 percent gravel 150 feet north and 2,500 feet east of the southwest or channers corner of sec. 18, T. 2 S., R. 16 E.; USGS Packsaddle Calcium carbonate equivalent: 1 to 5 percent Butte topographic quadrangle (lat. 45o39'13" N.; Electrical conductivity: 1 to 2 mmhos/cm long. 109o47'54" W.) Reaction: pH 7.4 to 8.4 A—0 to 4 inches; dark grayish brown (10YR 4/2) very Bk horizons gravelly sandy loam, very dark grayish brown Hue: 10YR or 2.5Y (10YR 3/2) moist; weak fine granular structure; Value: 5 to 7 dry; 4 to 6 moist soft, very friable, nonsticky, nonplastic; many very Chroma: 2 or 3 fine and fine roots; many very fine and fine pores; Texture (less than 2 mm): Clay loam, silty clay 40 percent gravel; neutral (pH 7.2); abrupt loam, or clay smooth boundary. 158 Soil Survey

E1—4 to 12 inches; grayish brown (10YR 5/2) very E2 horizon gravelly sandy loam, dark grayish brown (10YR Hue: 7.5YR, 10YR, or 2.5Y 4/2) moist; weak fine and medium subangular Value: 6 to 8 dry; 4 to 7 moist blocky structure; soft, very friable, slightly sticky, Chroma: 2 to 4 slightly plastic; many very fine and fine roots; Texture (less than 2 mm): Sandy loam or loam many very fine and fine pores; 45 percent gravel; Clay content: 5 to 15 percent neutral (pH 7.2); clear smooth boundary. Content of rock fragments: 35 to 70 percent—0 to E2—12 to 27 inches; light brownish gray (10YR 6/2) 10 percent cobbles; 35 to 60 percent gravel very gravelly sandy loam, dark grayish brown Reaction: pH 5.6 to 7.3 (10YR 4/2) moist; weak fine and medium E&Bt horizon subangular blocky structure; soft, very friable, Hue: 7.5YR, 10YR, or 2.5Y nonsticky, nonplastic; common fine roots; Value: E part 6 to 8, Bt part 4 to 6 dry; E part 4 to many very fine and fine pores; 45 percent gravel; 7, Bt part 4 or 5 moist 5 percent cobbles; neutral (pH 7.2); gradual Chroma: E part 2 to 4; Bt part 3 or 4 smooth boundary. Texture (less than 2 mm): Sandy loam, fine sandy E&Bt—27 to 45 inches; E part (80 percent) light loam, or loam brownish gray (10YR 6/2) extremely gravelly Clay content: 5 to 15 percent; lamellae have less sandy loam, dark grayish brown (10YR 4/2) than 5 percent clay increase moist; B part (20 percent) pale brown (10YR 6/3) 1 Content of rock fragments: 60 to 80 percent— sandy loam lamellae /4- to 1-inch thick, brown 10 to 25 percent cobbles; 40 to 55 percent (10YR 4/3) moist; weak medium and coarse gravel prismatic structure; soft, very friable, nonsticky, Reaction: pH 5.6 to 7.3 nonplastic; 50 percent gravel; 10 percent cobbles; neutral (pH 7.0); gradual smooth boundary. C horizon C—45 to 60 inches; light brownish gray (10YR 6/2) Hue: 7.5YR, 10YR, or 2.5Y extremely gravelly sandy loam, dark grayish Value: 5 to 7 dry; 4 or 5 moist brown (10YR 4/2) moist; massive; soft, very Chroma: 2 or 3 friable, nonsticky, nonplastic; few fine and Texture (less than 2 mm): Sandy loam or fine medium roots; many very fine and fine pores; sandy loam 50 percent gravel; 10 percent cobbles; neutral Clay content: 5 to 15 percent (pH 6.8). Content of rock fragments: 60 to 85 percent— 10 to 25 percent cobbles; 50 to 60 percent Range in Characteristics gravel Reaction: pH 5.6 to 7.3 Soil temperature: 42 to 47 degrees F Moisture control section: Between 8 and 24 inches A horizon Winspect Series Hue: 7.5YR or 10YR Depth class: Very deep (greater than 60 inches) Value: 4 to 6 dry; 3 or 4 moist Drainage class: Well drained Chroma: 2 or 3 Permeability: Moderate (0.6 to 2.0 inches/hour) Texture (less than 2 mm): Sandy loam Landform: Fan, hill, landslide, moraine, mountain, and Clay content: 7 to 15 percent fan on escarpment Content of rock fragments: 15 to 60 percent—0 to Parent material: Gravelly colluvium or alluvium 5 percent cobbles; 15 to 55 percent gravel weathered from limestone; gravelly glaciofluvial Reaction: pH 5.6 to 6.1 deposits; gravelly till; or gravelly colluvium E1 horizon weathered from limestone and sandstone Hue: 7.5YR or 10YR Slope range: 4 to 70 percent Value: 5 to 8 dry; 4 to 7 moist Elevation range: 4,200 to 6,200 feet Chroma: 2 to 4 Mean annual precipitation: 15 to 20 inches Texture (less than 2 mm): Sandy loam or loam Mean annual air temperature: 39 to 45 degrees F Clay content: 7 to 15 percent Frost-free period: 70 to 115 days Content of rock fragments: 15 to 60 percent—0 to 5 percent cobbles; 15 to 55 percent gravel Taxonomic Class: Loamy-skeletal, mixed, Reaction: pH 5.6 to 6.1 superactive, frigid Typic Calciustolls Sweet Grass County Area, Montana—Part I 159

Typical Pedon A horizon Hue: 10YR or 2.5Y Winspect cobbly loam, in an area of Winspect cobbly Value: 4 or 5 dry; 2 or 3 moist loam, 4 to 15 percent slopes, in an area of rangeland, Chroma: 1 or 2 1,400 feet north and 2,600 feet west of the southeast Texture (less than 2 mm): Loam corner of sec. 13, T. 3 S., R. 12 E.; USGS McLeod Clay content: 20 to 25 percent Basin topographic quadrangle (lat. 45o34'16" N.; long. Content of rock fragments: 15 to 35 percent—0 to 110o11'40" W.) 10 percent stones and cobbles; 10 to A1—0 to 6 inches; dark grayish brown (10YR 4/2) 15 percent gravel cobbly loam, black (10YR 2/1) moist; weak fine Calcium carbonate equivalent: 5 to 10 percent granular structure; soft, very friable, slightly Reaction: pH 7.4 to 8.4 sticky, nonplastic; many fine and medium roots; Ak horizon many very fine and fine pores; 15 percent gravel; Hue: 10YR or 2.5Y 8 percent cobbles; strongly effervescent; Value: 4 or 5 dry; 2 or 3 moist moderately alkaline (pH 8.2); abrupt smooth Chroma: 1 to 3 boundary. Texture (less than 2 mm): Loam or clay loam Ak—6 to 14 inches; dark gray (10YR 4/1) very cobbly Clay content: 20 to 30 percent loam, black (10YR 2/1) moist; weak medium Content of rock fragments: 20 to 60 percent—5 to subangular blocky structure; soft, very friable, 30 percent stones; 5 to 15 percent cobbles; slightly sticky, nonplastic; many fine and medium 10 to 30 percent gravel roots; many very fine and fine pores; few fine Calcium carbonate equivalent: 10 to 40 percent carbonate threads; 25 percent gravel; 10 percent Reaction: pH 7.4 to 8.4 cobbles; 5 percent stones; strongly effervescent; moderately alkaline pH 8.2); clear smooth Bk1 horizon boundary. Hue: 10YR or 2.5Y Bk1—14 to 27 inches; light brownish gray (10YR 6/2) Value: 5 or 6 dry; 4 or 5 moist very cobbly loam, dark grayish brown (10YR 4/2) Chroma: 2 to 4 moist; weak medium subangular blocky structure; Texture (less than 2 mm): Loam, clay loam, or soft, very friable, slightly sticky, slightly plastic; sandy clay loam common fine roots; many very fine and fine Clay content: 20 to 35 percent pores; common carbonate coats on undersides Content of rock fragments: 35 to 60 percent—5 to of rock fragments; common fine and medium 30 percent stones and cobbles; 20 to threads and soft masses of lime; 25 percent 35 percent gravel gravel; 15 percent cobbles; 5 percent stones; Calcium carbonate equivalent: 15 to 40 percent violently effervescent; moderately alkaline Reaction: pH 7.9 to 9.0 (pH 8.4); gradual smooth boundary. Bk2 horizon Bk2—27 to 60 inches; light brownish gray (10YR 6/2) Hue: 10YR or 2.5Y very cobbly loam, dark grayish brown (10YR 4/2) Value: 5 to 7 dry; 4 to 6 moist moist; weak medium and coarse subangular Chroma: 2 to 4 blocky structure; soft, very friable, slightly sticky, Texture (less than 2 mm): Loam, clay loam, or slightly plastic; few fine and medium roots; many sandy clay loam very fine and fine pores; common carbonate Clay content: 20 to 35 percent coats on undersides of rock fragments; many Content of rock fragments: 35 to 60 percent— fine and medium threads and soft masses of 10 to 30 percent stones and cobbles; 25 to lime; 30 percent gravel; 15 percent cobbles; 35 percent gravel 10 percent stones; violently effervescent; Calcium carbonate equivalent: 15 to 40 percent moderately alkaline (pH 8.4). Reaction: pH 7.9 to 9.0 Range in Characteristics Work Series Soil temperature: 41 to 47 degrees F Moisture control section: Between 4 and 12 inches Depth class: Deep (40 to 60 inches or more) Thickness of the mollic epipedon: 7 to 14 inches Drainage class: Well drained 160 Soil Survey

Permeability: Moderately slow (0.2 to 0.6 inch/hour) Bk2—30 to 60 inches; light brownish gray (10YR 6/2) Landform: Fan, hill, landslide, moraine, stream clay loam, grayish brown (10YR 5/2) moist; weak terrace, terrace, fan on escarpment, and swale on medium subangular blocky structure; moderately plain hard, firm, very sticky, very plastic; few very fine Parent material: Clayey alluvium or colluvium roots; common very fine pores; common coarse weathered from sandstone and shale soft masses of lime; strongly effervescent; slightly Slope range: 0 to 35 percent alkaline (pH 7.8). Elevation range: 4,200 to 6,200 feet Range in Characteristics Mean annual precipitation: 15 to 20 inches Mean annual air temperature: 39 to 45 degrees F Soil temperature: 41 to 47 degrees F Frost-free period: 70 to 115 days Moisture control section: Between 4 and 12 inches Thickness of the mollic epipedon: 7 to 16 inches Taxonomic Class: Fine, smectitic, frigid Typic Depth to the Bk horizon: 12 to 30 inches Argiustolls Note: Some pedons have a Btk horizon. A horizon Typical Pedon Hue: 7.5YR, 10YR, or 2.5Y Value: 4 or 5 dry; 2 or 3 moist Work clay loam, in an area of Work clay loam, 4 to Chroma: 2 or 3 8 percent slopes, in an area of rangeland, 1,900 feet Texture (less than 2 mm): Clay loam or loam south and 1,800 feet west of the northeast corner of Clay content: 15 to 40 percent sec. 18, T. 1 S., R. 16 E.; USGS Packsaddle Butte Content of rock fragments: 0 to 60 percent—0 to topographic quadrangle (lat. 45o44'56" N.; long. 30 percent stones and cobbles; 0 to 109o47'39" W.) 30 percent gravel A—0 to 5 inches; grayish brown (10YR 5/2) clay Reaction: pH 6.1 to 7.8 loam, very dark grayish brown (10YR 3/2) moist; Bt horizons strong medium granular structure; slightly hard, Hue: 7.5YR, 10YR, or 2.5Y friable, moderately sticky, moderately plastic; Value: 4 or 5 dry; 2 to 4 moist many very fine and fine roots; many very fine and Chroma: 2 or 3 fine pores; neutral (pH 7.2); abrupt smooth Texture (less than 2 mm): Clay loam or clay boundary. Clay content: 35 to 50 percent Bt1—5 to 14 inches; brown (10YR 5/3) clay loam, Content of rock fragments: 0 to 15 percent—0 to dark brown (10YR 3/3) moist; strong medium 5 percent stones and cobbles; 0 to 10 percent subangular blocky structure; moderately hard, gravel firm, very sticky, very plastic; common very fine Reaction: pH 6.6 to 7.8 and fine roots; many very fine and fine pores; common distinct continuous dark olive brown Bk horizons (2.5Y 3/3) moist; clay films on faces of peds; Hue: 10YR or 2.5Y neutral (pH 7.2); abrupt wavy boundary. Value: 5 to 7 dry; 4 to 6 moist Bt2—14 to 18 inches; grayish brown (10YR 5/2) clay Chroma: 2 to 4 loam, brown (10YR 4/3) moist; moderate medium Texture (less than 2 mm): Clay loam or loam subangular blocky structure; moderately hard, Clay content: 15 to 40 percent firm, very sticky, very plastic; common very fine Content of rock fragments: 0 to 35 percent—0 to and fine roots; many very fine and fine pores; 5 percent stones and cobbles; 0 to 30 percent common faint discontinuous dark olive brown gravel (2.5Y 3/3) moist; clay films on faces of peds; Calcium carbonate equivalent: 3 to 15 percent neutral (pH 7.2); abrupt wavy boundary. Electrical conductivity: 0 to 3 mmhos/cm Bk1—18 to 30 inches; light brownish gray (10YR 6/2), Reaction: pH 7.4 to 8.4 clay loam, grayish brown (10YR 5/2), crushed, moist; weak medium subangular blocky structure; moderately hard, firm, very sticky, very plastic; Worock Series few very fine and fine roots; many very fine and fine pores; few fine soft masses of lime; slightly Depth class: Very deep (greater than 60 inches) effervescent; slightly alkaline (pH 7.8); clear wavy Drainage class: Well drained boundary. Permeability: Moderately slow (0.2 to 0.6 inch/hour) Sweet Grass County Area, Montana—Part I 161

Landform: Mountain very fine and fine pores; common distinct Parent material: Gravelly colluvium or till discontinuous dark brown (10YR 3/3) moist; Slope range: 25 to 70 percent clay films on faces of peds and lining pores; Elevation range: 5,500 to 7,500 feet 35 percent gravel; 5 percent cobbles; slightly Mean annual precipitation: 20 to 25 inches acid (pH 6.2); clear smooth boundary. Mean annual air temperature: 36 to 38 degrees F Bt2—28 to 36 inches; brown (10YR 5/3) very gravelly Frost-free period: 50 to 70 days clay loam, dark yellowish brown (10YR 4/4) moist; weak medium and coarse subangular Taxonomic Class: Loamy-skeletal, mixed, blocky structure; slightly hard, firm, moderately superactive Eutric Haplocryalfs sticky, moderately plastic; few fine and medium roots; few very fine and fine pores; common faint Typical Pedon patchy brown (10YR 4/3) moist; clay films on Worock gravelly loam, in an area of Stemple-Worock faces of peds and lining pores; 35 percent gravel; complex, 35 to 70 percent slopes, very stony, in 10 percent cobbles; slightly acid (pH 6.4); clear an area of coniferous forest, 600 feet north and smooth boundary. 1,800 feet west of the southeast corner of sec. 13, BC—36 to 61 inches; light yellowish brown (10YR T. 3 S., R. 13 E.; USGS Squaw Peak topographic 6/4) very gravelly loam, brown (10YR 5/3) moist; quadrangle (lat. 45o34'12" N.; long. 110o03'36" W.) massive; slightly hard, friable, moderately sticky, moderately plastic; few fine roots; few very fine O—0 to 1 inch; partially decomposed forest litter; pores; 35 percent gravel; 10 percent cobbles; abrupt smooth boundary. 5 percent stones; slightly acid (pH 6.4). E1—1 to 4 inches; pale brown (10YR 6/3) gravelly loam, brown (10YR 4/3) dry; weak medium platy Range in Characteristics structure parting to weak fine granular; soft, very friable, slightly sticky, slightly plastic; few Soil temperature: 37 to 45 degrees F medium and common fine roots; common very Moisture control section: Between 4 and 12 inches fine and fine, few medium pores; 15 percent Depth to the Bt horizon: 6 to 20 inches gravel; 5 percent stones; slightly acid (pH 6.4); abrupt smooth boundary. E horizons E2—4 to 10 inches; light gray (10YR 7/2) gravelly Hue: 7.5YR, 10YR, or 2.5Y loam, brown (10YR 5/3) dry; weak fine and Value: 6 or 7 dry; 3 to 5 moist medium subangular blocky structure; soft, very Chroma: 2 to 4 or 6 friable, slightly sticky, slightly plastic; few medium Texture (less than 2 mm): Loam and coarse and common fine roots; common very Clay content: 18 to 27 percent fine and fine pores; 15 percent gravel; 5 percent Content of rock fragments: 10 to 50 percent—5 to cobbles; moderately acid (pH 6.0); clear smooth 35 percent stones and cobbles; 5 to boundary. 15 percent gravel E/Bt—10 to 17 inches; E part (70 percent) light Reaction: pH 5.1 to 6.5 brownish gray (10YR 6/2) very gravelly loam, E/Bt horizon brown (10YR 5/3) moist; Bt part (30 percent) Hue: 10YR or 2.5Y yellowish brown (10YR 5/4) gravelly clay loam, Value: E part—6 or 7, Bt part—5 or 6 dry; E dark yellowish brown (10YR 4/4) moist; weak fine part—3 to 5, Bt part—4 or 5 moist and medium subangular blocky structure; slightly Chroma: E part—2 to 4 or 6; Bt part—3, 4, or 6 hard, friable, slightly sticky, slightly plastic; few Texture (less than 2 mm): E part—loam or sandy fine to coarse roots; common very fine and fine loam; Bt part—clay loam or loam pores; common distinct discontinuous dark brown Clay content: 18 to 30 percent (10YR 3/3) moist; clay films on faces of peds and Content of rock fragments: 20 to 60 percent— lining pores; 30 percent gravel; 10 percent 10 to 35 percent stones and cobbles; 10 to cobbles; slightly acid (pH 6.2); clear smooth 35 percent gravel boundary. Reaction: pH 5.1 to 6.5 Bt1—17 to 28 inches; yellowish brown (10YR 5/4) very gravelly clay loam, brown (10YR 4/3) moist; Bt horizons moderate medium and coarse subangular blocky Hue: 7.5YR or 10YR structure; slightly hard, firm, very sticky, very Value: 5 to 7 dry; 4 or 5 moist plastic; few fine to coarse roots; common Chroma: 3, 4, or 6 162 Soil Survey

Texture (less than 2 mm): Clay loam, loam, or pores; moderately alkaline (pH 8.0); clear smooth sandy clay loam boundary. Clay content: 25 to 35 percent Bw2—10 to 18 inches; light brownish gray (2.5Y 6/2) Content of rock fragments: 35 to 65 percent—5 to loam, grayish brown (2.5Y 5/2) moist; weak 25 percent cobbles; 25 to 35 percent gravel coarse prismatic structure; slightly hard, very Reaction: pH 5.6 to 6.5 friable, slightly sticky, slightly plastic; many very fine and fine roots; common very fine and fine BC horizon pores; slightly effervescent; moderately alkaline Hue: 7.5YR or 10YR (pH 8.2); abrupt smooth boundary. Value: 6 or 7 dry; 4 to 6 moist Bk1—18 to 24 inches; grayish brown (2.5Y 5/2) loam, Chroma: 3, 4, or 6 dark grayish brown (2.5Y 4/2) moist; weak coarse Texture (less than 2 mm): Loam, clay loam, or prismatic structure; slightly hard, very friable, sandy clay loam slightly sticky, slightly plastic; common fine roots; Clay content: 20 to 35 percent common very fine and fine pores; many fine Content of rock fragments: 35 to 60 percent— threads and soft masses of lime; strongly 10 to 25 percent stones and cobbles; 25 to effervescent; moderately alkaline (pH 8.2); clear 45 percent gravel smooth boundary. Reaction: pH 5.6 to 6.5 Bk2—24 to 36 inches; light olive brown (2.5Y 5/4) silt loam, dark grayish brown (2.5Y 4/2) moist; weak coarse prismatic structure; soft, very friable, Yamacall Series slightly sticky, slightly plastic; common fine roots; common very fine and fine pores; common fine Depth class: Very deep (greater than 60 inches) soft masses of lime; strongly effervescent; Drainage class: Well drained moderately alkaline (pH 8.2); clear smooth Permeability: Moderate (0.6 to 2.0 inches/hour) boundary. Landform: Escarpment, fan, hill, stream terrace, and Bk3—36 to 60 inches; light olive brown (2.5Y 5/4) silt swale on plain loam, dark grayish brown (2.5Y 4/2) moist; weak Parent material: Loamy alluvium coarse prismatic structure; soft, very friable, Slope range: 1 to 15 percent slightly sticky, slightly plastic; few very fine roots; Elevation range: 3,750 to 5,600 feet common very fine pores; common fine soft Mean annual precipitation: 10 to 14 inches masses of lime; 5 percent gravel; strongly Mean annual air temperature: 43 to 46 degrees F effervescent; moderately alkaline (pH 8.4). Frost-free period: 95 to 125 days Range in Characteristics Taxonomic Class: Fine-loamy, mixed, superactive, Soil temperature: 42 to 47 degrees F frigid Aridic Haplustepts Moisture control section: Between 4 and 12 inches Typical Pedon Depth to the Bk horizon: 10 to 20 inches Note: Some pedons have a BC horizon with a clay Yamacall loam, in an area of Yamacall loam, 1 to content of 5 to 15 percent. 4 percent slopes, in an area of cropland, 2,600 feet south and 1,500 feet east of the northwest corner of A horizon sec. 5, T. 4 N., R. 16 E.; USGS Gougley Creek Hue: 10YR, 2.5Y, or 5Y topographic quadrangle (lat. 46o07'31" N.; long. Value: 5 or 6 dry; 3 to 5 moist 109o45'51" W.) Chroma: 2 to 4 Texture (less than 2 mm): Loam or clay loam Ap—0 to 6 inches; grayish brown (2.5Y 5/2) loam, Clay content: 18 to 35 percent dark grayish brown (2.5Y 4/2) moist; weak fine Content of rock fragments: 0 to 15 percent—0 to granular structure; slightly hard, very friable, 5 percent cobbles; 0 to 10 percent gravel slightly sticky, slightly plastic; many very fine Reaction: pH 6.6 to 8.4 roots; many fine pores; slightly alkaline (pH 7.6); abrupt smooth boundary. Bw horizons Bw1—6 to 10 inches; grayish brown (2.5Y 5/2) loam, Hue: 10YR, 2.5Y, or 5Y dark grayish brown (2.5Y 4/2) moist; moderate Value: 5 to 7 dry; 4 to 6 moist medium subangular blocky structure; soft, very Chroma: 2 to 4 friable, slightly sticky, slightly plastic; many very Texture (less than 2 mm): Loam, clay loam, or silt fine and fine roots; common very fine and fine loam Sweet Grass County Area, Montana—Part I 163

Clay content: 18 to 30 percent medium subangular blocky structure; moderately Content of rock fragments: 0 to 15 percent—0 to hard, friable, very sticky, very plastic; many very 5 percent cobbles; 0 to 10 percent gravel fine and fine roots; common very fine pores; Calcium carbonate equivalent: 0 to 5 percent 10 percent channers; slightly effervescent; Reaction: pH 6.6 to 8.4 moderately alkaline (pH 8.2); abrupt wavy boundary. Bk horizons Bk—6 to 14 inches; olive gray (5Y 5/2) clay, olive gray Hue: 10YR, 2.5Y, or 5Y (5Y 4/2) moist; moderate coarse prismatic Value: 5 to 8 dry; 4 to 6 moist structure parting to moderate medium subangular Chroma: 2 to 4 blocky; very hard, friable, very sticky, very Texture (less than 2 mm): Loam, clay loam, or silt plastic; common very fine roots; few very fine loam tubular pores; common fine soft masses of lime; Clay content: 18 to 30 percent 10 percent channers; strongly effervescent; Content of rock fragments: 0 to 15 percent—0 to strongly alkaline (pH 8.6); abrupt wavy boundary. 5 percent cobbles; 0 to 10 percent gravel Cr—14 to 60 inches; fractured calcareous shale; Calcium carbonate equivalent: 5 to 15 percent breaks into small angular blocks; violently Electrical conductivity: 0 to 4 mmhos/cm effervescent. Sodium adsorption ratio: 1 to 5 Gypsum content: 0 to 1 percent Range in Characteristics Reaction: pH 7.9 to 9.0 Soil temperature: 42 to 47 degrees F Moisture control section: Between 4 and 12 inches Yawdim Series Depth to the Bk horizon: 4 to 9 inches Depth to the Cr horizon: 10 to 20 inches Depth class: Shallow (10 to 20 inches) A horizon Drainage class: Well drained Hue: 10YR or 2.5Y Permeability: Slow (0.06 to 0.20 inch/hour) Value: 5 or 6 dry; 3 or 4 moist Landform: Escarpment, hill, and knoll on plain Chroma: 2 Parent material: Clayey residuum weathered from Texture (less than 2 mm): Clay or clay loam calcareous shale Clay content: 27 to 50 percent Slope range: 2 to 60 percent Content of rock fragments: 0 to 15 percent gravel Elevation range: 3,750 to 5,200 feet or channers Mean annual precipitation: 10 to 14 inches Reaction: pH 6.6 to 7.8 Mean annual air temperature: 43 to 46 degrees F Frost-free period: 95 to 125 days Bw horizon Hue: 10YR, 2.5Y, or 5Y Taxonomic Class: Clayey, smectitic, calcareous, Value: 5 to 7 dry; 4 or 5 moist frigid, shallow Aridic Ustorthents Chroma: 2 or 3 Texture (less than 2 mm): Clay, clay loam, or silty Typical Pedon clay Yawdim clay, in an area of Tanna-Yawdim complex, Clay content: 35 to 50 percent 2 to 8 percent slopes, in an area of rangeland, Content of rock fragments: 0 to 15 percent gravel 1,600 feet north and 500 feet west of the southeast or channers corner of sec. 30, T. 3 N., R. 15 E.; USGS Otter Creek Calcium carbonate equivalent: 5 to 10 percent School topographic quadrangle (lat. 45o58'41" N.; Reaction: pH 7.4 to 8.4 long. 109o53'53" W.) Bk horizon A—0 to 2 inches; grayish brown (2.5Y 5/2) clay, dark Hue: 10YR, 2.5Y, or 5Y grayish brown (2.5Y 4/2) moist; moderate thick Value: 5 to 8 dry; 4 to 6 moist platy structure parting to weak fine granular; Chroma: 1 to 4 moderately hard, friable, very sticky, very plastic; Texture (less than 2 mm): Clay, clay loam, or silty common very fine and fine roots; common very clay fine pores; 10 percent channers; slightly Clay content: 35 to 50 percent effervescent; slightly alkaline (pH 7.8); abrupt Content of rock fragments: 0 to 15 percent gravel wavy boundary. or channers; 0 to 50 percent soft shale chips Bw—2 to 6 inches; grayish brown (2.5Y 5/2) clay, Calcium carbonate equivalent: 5 to 10 percent dark grayish brown (2.5Y 4/2) moist; moderate Reaction: pH 7.4 to 8.6 173

Detailed Soil Map Units

The map units delineated on the detailed soil they are not mentioned in the descriptions, especially maps in this survey represent the soils or where the pattern was so complex that it was miscellaneous areas in the survey area. The map unit impractical to make enough observations to identify descriptions in this section, along with the maps, can all of the soils and miscellaneous areas on the be used to determine the suitability and potential of a landscape. unit for specific uses. They also can be used to plan The presence of minor components in a map unit the management needed for those uses. in no way diminishes the usefulness or accuracy of A map unit delineation on a soil map represents an the data. The objective of mapping is not to delineate area dominated by one or more major kinds of soil or pure taxonomic classes but rather to separate the miscellaneous areas. A map unit is identified and landscape into landforms or landform segments that named according to the taxonomic classification of have similar use and management requirements. The the dominant soils. Within a taxonomic class, there delineation of such segments on the map provides are precisely defined limits for the properties of the sufficient information for the development of resource soils. On the landscape, however, the soils are plans. If intensive use of small areas is planned, natural phenomena, and they have the characteristic however, onsite investigation is needed to define and variability of all natural phenomena. Thus, the range locate the soils and miscellaneous areas. of some observed properties may extend beyond the An identifying symbol precedes the map unit name limits defined for a taxonomic class. Areas of soils of in the map unit descriptions. Each description a single taxonomic class rarely, if ever, can be includes general facts about the unit. mapped without including areas of other taxonomic Soils that have profiles that are almost alike make classes. Consequently, every map unit is made up of up a soil series. Except for differences in texture of the soils or miscellaneous areas for which it is named the surface layer, all of the soils of a series have and some minor components that belong to major horizons that are similar in composition, taxonomic classes other than those of the major thickness, and arrangement. soils. Soils of one series can differ in texture of the Most minor soils have properties similar to those of surface layer, slope, stoniness, salinity, degree of the dominant soil or soils in the map unit, and thus erosion, and other characteristics that affect their use. they do not affect use and management. These are On the basis of such differences, a soil series is called noncontrasting, or similar, components. They divided into soil phases. Most of the areas shown on may or may not be mentioned in a particular map unit the detailed soil maps are phases of soil series. The description. Other minor components, however, have name of a soil phase commonly indicates a feature properties and behavioral characteristics divergent that affects use or management. For example, enough to affect use or to require different Hinterland clay loam, 0 to 8 percent slopes, is a management. These are called contrasting, or phase of the Hinterland series. dissimilar, components. They generally are in small Some map units are made up of two or more major areas and could not be mapped separately because soils or miscellaneous areas. These map units are of the scale used. Some small areas of strongly complexes, associations, or undifferentiated groups. contrasting soils or miscellaneous areas are This survey includes complexes. They consist of identified by a special symbol on the maps. The two or more soils or miscellaneous areas in such an contrasting components are mentioned in the map intricate pattern or in such small areas that they unit descriptions. A few areas of minor components cannot be shown separately on the maps. The may not have been observed, and, consequently, pattern and proportion of the soils or miscellaneous 174 Soil Survey

areas are somewhat similar in all areas. Cabbart- Clunton and similar soils Tanna complex, 2 to 8 percent slopes, is an example. Composition: 25 percent This survey includes miscellaneous areas. They Geomorphic description: Depression and flood plain have little or no soil material and support little or no Slope: 0 to 4 percent vegetation. Rock outcrop is an example. Elevation: 3,750 to 4,300 feet The “Acreage and Proportionate Extent of the Effective annual precipitation: 10 to 14 inches Soils” table gives the acreage and proportionate Frost-free period: 95 to 130 days extent of each map unit. Other tables (see “Summary Surface layer texture: Muck of Tables”) give properties of the soils and the Drainage class: Very poorly drained limitations, capabilities, and potentials for many uses. Parent material: Fine-loamy alluvium over sandy and Many of the terms used in describing the soils or gravelly alluvium miscellaneous areas are defined in the “Glossary.” Native plant cover type: Rangeland Flooding: Frequent Water table: Present 100B—Nesda-Meadowcreek-Clunton Ponding duration: Brief loams, 0 to 4 percent slopes Available water capacity: Mainly 10.2 inches

Setting Additional Components Field investigation intensity: Order 2 McIlwaine and similar soils: 5 percent Elevation: 3,750 to 4,300 feet Mean annual precipitation: 10 to 14 inches Management Frost-free period: 95 to 130 days For management information about this map unit, Major Component Description see appropriate sections in Part II of this publication. Nesda and similar soils Composition: 40 percent Geomorphic description: Flood plain 102B—Ledger family, clay loam, Slope: 0 to 4 percent 1 to 4 percent slopes Elevation: 3,750 to 4,300 feet Effective annual precipitation: 10 to 14 inches Setting Frost-free period: 95 to 130 days Surface layer texture: Loam Elevation: 3,750 to 5,200 feet Drainage class: Well drained Mean annual precipitation: 10 to 14 inches Parent material: Sandy and gravelly alluvium Frost-free period: 95 to 125 days Native plant cover type: Forestland Flooding: Occasional Major Component Description Available water capacity: Mainly 3.8 inches Ledger and similar soils Meadowcreek and similar soils Composition: 85 percent Composition: 30 percent Geomorphic description: Flood plain Geomorphic description: Flood plain Slope: 1 to 4 percent Slope: 0 to 2 percent Elevation: 3,750 to 5,200 feet Elevation: 3,750 to 4,300 feet Effective annual precipitation: 10 to 14 inches Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Frost-free period: 95 to 130 days Surface layer texture: Clay loam Surface layer texture: Loam Drainage class: Somewhat poorly drained Drainage class: Somewhat poorly drained Parent material: Clayey alluvium Parent material: Fine-loamy over sandy and gravelly Native plant cover type: Rangeland alluvium Flooding: Rare Native plant cover type: Rangeland Water table: Present Flooding: Rare Salt affected: Saline within 30 inches Water table: Present Sodium affected: Sodic within 30 inches Available water capacity: Mainly 6.3 inches Available water capacity: Mainly 6.9 inches Sweet Grass County Area, Montana—Part I 175

Additional Components Major Component Description Klayent and similar soils: 5 percent Meadowcreek and similar soils Kobase and similar soils: 5 percent Composition: 85 percent Thibadeau and similar soils: 5 percent Geomorphic description: Flood plain Slope: 0 to 2 percent Management Elevation: 3,750 to 6,000 feet For management information about this map unit, Effective annual precipitation: 10 to 19 inches see appropriate sections in Part II of this publication. Frost-free period: 85 to 125 days Surface layer texture: Loam Drainage class: Somewhat poorly drained 103A—Havre loam, 0 to 2 percent slopes Parent material: Fine-loamy over sandy and gravelly alluvium Native plant cover type: Rangeland Setting Flooding: Rare Elevation: 3,750 to 5,200 feet Water table: Present Mean annual precipitation: 10 to 14 inches Available water capacity: Mainly 6.3 inches Frost-free period: 95 to 125 days Additional Components Major Component Description Fairway and similar soils: 5 percent Nesda and similar soils: 5 percent Havre and similar soils Swampcreek and similar soils: 5 percent Composition: 85 percent Management Geomorphic description: Flood plain Slope: 0 to 2 percent For management information about this map unit, Elevation: 3,750 to 5,200 feet see appropriate sections in Part II of this publication. Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Surface layer texture: Loam 106B—Thibadeau loam, channeled, Drainage class: Well drained saline, 0 to 4 percent slopes Parent material: Loamy alluvium Native plant cover type: Rangeland Setting Flooding: Rare Elevation: 3,750 to 5,200 feet Available water capacity: Mainly 9.6 inches Mean annual precipitation: 10 to 14 inches Additional Components Frost-free period: 95 to 125 days Ledger and similar soils: 7 percent Major Component Description Klayent and similar soils: 4 percent Thibadeau and similar soils Yamacall and similar soils: 4 percent Composition: 85 percent Management Geomorphic description: Flood plain Slope: 0 to 4 percent For management information about this map unit, Elevation: 3,750 to 5,200 feet see appropriate sections in Part II of this publication. Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days 104A—Meadowcreek loam, 0 to 2 percent Surface layer texture: Loam slopes Drainage class: Moderately well drained Parent material: Loamy alluvium Native plant cover type: Rangeland Setting Flooding: Rare Elevation: 3,750 to 6,000 feet Water table: Present Mean annual precipitation: 10 to 19 inches Salt affected: Saline within 30 inches Frost-free period: 85 to 125 days Available water capacity: Mainly 6.5 inches 176 Soil Survey

Additional Components Management Lallie and similar soils: 5 percent For management information about this map unit, Ledger and similar soils: 5 percent see appropriate sections in Part II of this publication. Yamacall and similar soils: 5 percent Management 109A—Meadowcreek-Nesda loams, For management information about this map unit, 0 to 2 percent slopes see appropriate sections in Part II of this publication.

Setting 107A—Nesda-McIlwaine loams, 0 to 2 percent slopes Field investigation intensity: Order 2 Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Setting Frost-free period: 85 to 115 days Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Major Component Description Frost-free period: 85 to 115 days Meadowcreek and similar soils Major Component Description Composition: 50 percent Nesda and similar soils Geomorphic description: Flood plain Composition: 50 percent Slope: 0 to 2 percent Geomorphic description: Flood plain Elevation: 4,200 to 6,000 feet Slope: 0 to 2 percent Effective annual precipitation: 15 to 19 inches Elevation: 4,200 to 6,000 feet Frost-free period: 85 to 115 days Effective annual precipitation: 15 to 19 inches Surface layer texture: Loam Frost-free period: 85 to 115 days Drainage class: Somewhat poorly drained Surface layer texture: Loam Parent material: Fine-loamy over sandy and gravelly Drainage class: Well drained alluvium Parent material: Sandy and gravelly alluvium Native plant cover type: Rangeland Native plant cover type: Forestland Flooding: Rare Flooding: Occasional Water table: Present Available water capacity: Mainly 3.8 inches Available water capacity: Mainly 6.3 inches

McIlwaine and similar soils Nesda and similar soils Composition: 40 percent Composition: 40 percent Geomorphic description: Flood plain Geomorphic description: Flood plain Slope: 0 to 2 percent Slope: 0 to 2 percent Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Surface layer texture: Loam Surface layer texture: Loam Drainage class: Somewhat poorly drained Drainage class: Well drained Parent material: Coarse-loamy over sandy and Parent material: Sandy and gravelly alluvium gravelly alluvium Native plant cover type: Forestland Native plant cover type: Forestland Flooding: Occasional Flooding: Rare Available water capacity: Mainly 3.8 inches Water table: Present Additional Components Available water capacity: Mainly 5.4 inches Albicalis and similar soils: 3 percent Additional Components Fairway and similar soils: 3 percent Albicalis and similar soils: 5 percent Korchea and similar soils: 2 percent Meadowcreek and similar soils: 5 percent McIlwaine and similar soils: 2 percent Sweet Grass County Area, Montana—Part I 177

Management Major Component Description For management information about this map unit, Cabbart and similar soils see appropriate sections in Part II of this publication. Composition: 85 percent Geomorphic description: • Nose slope summit on hill 110D—Cabbart loam, 2 to 15 percent • Nose slope backslope on hill slopes • Interfluve summit on hill • Side slope backslope on hill Setting Slope: 15 to 35 percent Elevation: 3,750 to 5,200 feet Field investigation intensity: Order 2 Effective annual precipitation: 10 to 14 inches Elevation: 3,750 to 5,200 feet Frost-free period: 95 to 125 days Mean annual precipitation: 10 to 14 inches Surface layer texture: Loam Frost-free period: 95 to 125 days Depth to bedrock (paralithic): 10 to 20 inches Major Component Description Drainage class: Well drained Parent material: Loamy residuum weathered from Cabbart and similar soils sandstone and siltstone Composition: 85 percent Native plant cover type: Rangeland Geomorphic description: Knoll and plain Available water capacity: Mainly 3.0 inches Slope: 2 to 15 percent Elevation: 3,750 to 5,200 feet Additional Components Effective annual precipitation: 10 to 14 inches Delpoint and similar soils: 5 percent Frost-free period: 95 to 125 days Rock outcrop: 4 percent Surface layer texture: Loam Rentsac and similar soils: 3 percent Depth to bedrock (paralithic): 10 to 20 inches Yawdim and similar soils: 3 percent Drainage class: Well drained Parent material: Loamy residuum weathered from Management sandstone and siltstone For management information about this map unit, Native plant cover type: Rangeland see appropriate sections in Part II of this publication. Available water capacity: Mainly 3.0 inches Additional Components Delpoint and similar soils: 5 percent 112C—Cabbart-Delpoint, calcareous, Megonot and similar soils: 4 percent loams, 2 to 8 percent slopes Rentsac and similar soils: 2 percent Rock outcrop: 2 percent Setting Yawdim and similar soils: 2 percent Field investigation intensity: Order 2 Management Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches For management information about this map unit, Frost-free period: 95 to 125 days see appropriate sections in Part II of this publication. Major Component Description 110E—Cabbart loam, 15 to 35 percent Cabbart and similar soils slopes Composition: 50 percent Geomorphic description: Knoll and plain Slope: 2 to 8 percent Setting Elevation: 3,750 to 5,200 feet Field investigation intensity: Order 2 Effective annual precipitation: 10 to 14 inches Elevation: 3,750 to 5,200 feet Frost-free period: 95 to 125 days Mean annual precipitation: 10 to 14 inches Surface layer texture: Loam Frost-free period: 95 to 125 days Depth to bedrock (paralithic): 10 to 20 inches 178 Soil Survey

Drainage class: Well drained Native plant cover type: Rangeland Parent material: Loamy residuum weathered from Available water capacity: Mainly 3.0 inches sandstone and siltstone Native plant cover type: Rangeland Delpoint and similar soils Available water capacity: Mainly 3.0 inches Composition: 40 percent Geomorphic description: Plain and swale Delpoint and similar soils Slope: 8 to 15 percent Composition: 40 percent Elevation: 3,750 to 5,200 feet Geomorphic description: Plain and swale Effective annual precipitation: 10 to 14 inches Slope: 2 to 8 percent Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Surface layer texture: Loam Effective annual precipitation: 10 to 14 inches Depth to bedrock (paralithic): 20 to 40 inches Frost-free period: 95 to 125 days Drainage class: Well drained Surface layer texture: Loam Parent material: Loamy residuum weathered from Depth to bedrock (paralithic): 20 to 40 inches sandstone and siltstone Drainage class: Well drained Native plant cover type: Rangeland Parent material: Loamy residuum weathered from Available water capacity: Mainly 4.6 inches sandstone and siltstone Additional Components Native plant cover type: Rangeland Available water capacity: Mainly 4.6 inches Yamacall and similar soils: 4 percent Rentsac and similar soils: 2 percent Additional Components Rock outcrop: 2 percent Yamacall and similar soils: 4 percent Yawdim and similar soils: 2 percent Boxwell and similar soils: 2 percent Management Rentsac and similar soils: 2 percent Yawdim and similar soils: 2 percent For management information about this map unit, see appropriate sections in Part II of this publication. Management For management information about this map unit, see appropriate sections in Part II of this publication. 112E—Cabbart-Delpoint, calcareous loams, 15 to 35 percent slopes 112D—Cabbart-Delpoint, calcareous, loams, 8 to 15 percent slopes Setting Elevation: 3,750 to 5,200 feet Setting Mean annual precipitation: 10 to 14 inches Field investigation intensity: Order 2 Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Major Component Description Mean annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Cabbart and similar soils Composition: 50 percent Major Component Description Geomorphic description: Cabbart and similar soils • Nose slope summit on hill Composition: 50 percent • Nose slope backslope on hill Geomorphic description: Knoll and plain • Side slope backslope on hill Slope: 8 to 15 percent Slope: 15 to 35 percent Elevation: 3,750 to 5,200 feet Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Frost-free period: 95 to 125 days Surface layer texture: Loam Surface layer texture: Loam Depth to bedrock (paralithic): 10 to 20 inches Depth to bedrock (paralithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained Parent material: Loamy residuum weathered from Parent material: Loamy residuum weathered from sandstone and siltstone sandstone and siltstone Sweet Grass County Area, Montana—Part I 179

Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 3.0 inches Available water capacity: Mainly 2.4 inches

Delpoint and similar soils Rentsac and similar soils Composition: 40 percent Composition: 30 percent Geomorphic description: Geomorphic description: Knoll and plain • Base slope backslope on hill Slope: 2 to 15 percent • Base slope footslope on hill Elevation: 3,750 to 5,200 feet • Side slope backslope on hill Effective annual precipitation: 10 to 14 inches Slope: 15 to 35 percent Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Surface layer texture: Channery loam Effective annual precipitation: 10 to 14 inches Depth to bedrock (lithic): 10 to 20 inches Frost-free period: 95 to 125 days Drainage class: Well drained Surface layer texture: Loam Parent material: Residuum weathered from Depth to bedrock (paralithic): 20 to 40 inches calcareous sandstone Drainage class: Well drained Native plant cover type: Rangeland Parent material: Loamy residuum weathered from Available water capacity: Mainly 1.4 inches sandstone and siltstone Native plant cover type: Rangeland Cabbart and similar soils Available water capacity: Mainly 3.8 inches Composition: 20 percent Geomorphic description: Knoll and plain Additional Components Slope: 2 to 15 percent Rock outcrop: 4 percent Elevation: 3,750 to 5,200 feet Yamacall and similar soils: 4 percent Effective annual precipitation: 10 to 14 inches Rentsac and similar soils: 2 percent Frost-free period: 95 to 125 days Surface layer texture: Loam Management Depth to bedrock (paralithic): 10 to 20 inches For management information about this map unit, Drainage class: Well drained see appropriate sections in Part II of this publication. Parent material: Loamy residuum weathered from sandstone and siltstone Native plant cover type: Rangeland 115D—Yawdim-Rentsac-Cabbart complex, Available water capacity: Mainly 3.0 inches 2 to 15 percent slopes Additional Components Reedpoint and similar soils: 3 percent Setting Delpoint and similar soils: 2 percent Hinterland and similar soils: 2 percent Elevation: 3,750 to 5,200 feet Tanna and similar soils: 2 percent Mean annual precipitation: 10 to 14 inches Rock outcrop: 1 percent Frost-free period: 95 to 125 days Management Major Component Description For management information about this map unit, Yawdim and similar soils see appropriate sections in Part II of this publication. Composition: 40 percent Geomorphic description: Knoll and plain Slope: 2 to 15 percent 116F—Cabbart-Rock outcrop complex, Elevation: 3,750 to 5,200 feet 15 to 60 percent slopes Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Setting Surface layer texture: Clay loam Depth to bedrock (paralithic): 10 to 20 inches Field investigation intensity: Order 2 Drainage class: Well drained Elevation: 3,750 to 5,200 feet Parent material: Clayey residuum weathered from Mean annual precipitation: 10 to 14 inches calcareous shale Frost-free period: 95 to 125 days 180 Soil Survey

Major Component Description Drainage class: Well drained Parent material: Loamy residuum weathered from Cabbart and similar soils sandstone and siltstone Composition: 70 percent Native plant cover type: Rangeland Geomorphic description: Available water capacity: Mainly 3.0 inches • Nose slope summit on escarpment • Nose slope backslope on escarpment Tanna and similar soils • Side slope backslope on escarpment Composition: 40 percent Slope: 15 to 60 percent Geomorphic description: Plain and swale Elevation: 3,750 to 5,200 feet Slope: 2 to 8 percent Effective annual precipitation: 10 to 14 inches Elevation: 3,750 to 5,200 feet Frost-free period: 95 to 125 days Effective annual precipitation: 10 to 14 inches Surface layer texture: Loam Frost-free period: 95 to 125 days Depth to bedrock (paralithic): 10 to 20 inches Surface layer texture: Clay loam Drainage class: Well drained Depth to bedrock (paralithic): 20 to 40 inches Parent material: Loamy residuum weathered from Drainage class: Well drained sandstone and siltstone Parent material: Clayey residuum weathered from Native plant cover type: Rangeland sandstone and shale Available water capacity: Mainly 3.0 inches Native plant cover type: Rangeland Available water capacity: Mainly 4.2 inches Rock outcrop Composition: 20 percent Additional Components Definition: Rock outcrop consists mainly of areas of Hinterland and similar soils: 4 percent exposed hard bedrock. Ethridge and similar soils: 2 percent Geomorphic description: Escarpment Yawdim and similar soils: 2 percent Additional Components Delpoint and similar soils: 1 percent Reedpoint and similar soils: 1 percent Delpoint and similar soils: 4 percent Rentsac and similar soils: 3 percent Management Yamacall and similar soils: 3 percent For management information about this map unit, Management see appropriate sections in Part II of this publication. For management information about this map unit, see appropriate sections in Part II of this publication. 118C—Hinterland clay loam, 0 to 8 percent slopes

117C—Cabbart-Tanna complex, Setting 2 to 8 percent slopes Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Setting Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Major Component Description Mean annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Hinterland and similar soils Composition: 85 percent Major Component Description Geomorphic description: Knoll and plain Cabbart and similar soils Slope: 0 to 8 percent Composition: 50 percent Elevation: 3,750 to 5,200 feet Geomorphic description: Knoll and plain Effective annual precipitation: 10 to 14 inches Slope: 2 to 8 percent Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Surface layer texture: Clay loam Effective annual precipitation: 10 to 14 inches Depth to bedrock (lithic): 10 to 20 inches Frost-free period: 95 to 125 days Drainage class: Well drained Surface layer texture: Loam Parent material: Residuum weathered from Depth to bedrock (paralithic): 10 to 20 inches sandstone Sweet Grass County Area, Montana—Part I 181

Native plant cover type: Rangeland 129C—Tanna-Cabbart complex, Available water capacity: Mainly 2.0 inches 2 to 8 percent slopes Additional Components Setting Tanna and similar soils: 7 percent Cabbart and similar soils: 5 percent Elevation: 3,750 to 5,200 feet Boxwell and similar soils: 2 percent Mean annual precipitation: 10 to 14 inches Reedpoint and similar soils: 1 percent Frost-free period: 95 to 125 days Management Major Component Description For management information about this map unit, Tanna and similar soils see appropriate sections in Part II of this publication. Composition: 50 percent Geomorphic description: Plain and swale Slope: 2 to 8 percent 127C—Marmarth loam, 2 to 8 percent Elevation: 3,750 to 5,200 feet slopes Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Surface layer texture: Clay loam Setting Depth to bedrock (paralithic): 20 to 40 inches Drainage class: Well drained Elevation: 3,750 to 5,200 feet Parent material: Clayey residuum weathered from Mean annual precipitation: 10 to 14 inches sandstone and shale Frost-free period: 95 to 125 days Native plant cover type: Rangeland Available water capacity: Mainly 4.2 inches Major Component Description Marmarth and similar soils Cabbart and similar soils Composition: 85 percent Composition: 40 percent Geomorphic description: Plain and swale Geomorphic description: Knoll and plain Slope: 2 to 8 percent Slope: 2 to 8 percent Elevation: 3,750 to 5,200 feet Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Frost-free period: 95 to 125 days Surface layer texture: Loam Surface layer texture: Loam Depth to bedrock (paralithic): 20 to 40 inches Depth to bedrock (paralithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained Parent material: Loamy residuum weathered from Parent material: Loamy residuum weathered from sandstone and siltstone sandstone and siltstone Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 5.6 inches Available water capacity: Mainly 3.0 inches Additional Components Additional Components Hinterland and similar soils: 4 percent Boxwell and similar soils: 4 percent Tanna and similar soils: 4 percent Delpoint and similar soils: 2 percent Delpoint and similar soils: 3 percent Kremlin and similar soils: 2 percent Cabbart and similar soils: 2 percent Marmarth and similar soils: 1 percent Reedpoint and similar soils: 2 percent Yawdim and similar soils: 1 percent Management Management For management information about this map unit, For management information about this map unit, see appropriate sections in Part II of this publication. see appropriate sections in Part II of this publication. 182 Soil Survey

129D—Tanna-Cabbart complex, 130C—Tanna-Hinterland clay loams, 8 to 15 percent slopes 2 to 8 percent slopes

Setting Setting Elevation: 3,750 to 5,200 feet Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Mean annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Frost-free period: 95 to 125 days Major Component Description Major Component Description Tanna and similar soils Tanna and similar soils Composition: 50 percent Composition: 50 percent Geomorphic description: Plain and swale Geomorphic description: Plain and swale Slope: 8 to 15 percent Slope: 2 to 8 percent Elevation: 3,750 to 5,200 feet Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Frost-free period: 95 to 125 days Surface layer texture: Clay loam Surface layer texture: Clay loam Depth to bedrock (paralithic): 20 to 40 inches Depth to bedrock (paralithic): 20 to 40 inches Drainage class: Well drained Drainage class: Well drained Parent material: Clayey residuum weathered from Parent material: Clayey residuum weathered from sandstone and shale sandstone and shale Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 4.2 inches Available water capacity: Mainly 4.2 inches

Cabbart and similar soils Hinterland and similar soils Composition: 40 percent Composition: 40 percent Geomorphic description: Knoll and plain Geomorphic description: Knoll and plain Slope: 8 to 15 percent Slope: 2 to 8 percent Elevation: 3,750 to 5,200 feet Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Frost-free period: 95 to 125 days Surface layer texture: Loam Surface layer texture: Clay loam Depth to bedrock (paralithic): 10 to 20 inches Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained Parent material: Loamy residuum weathered from Parent material: Residuum weathered from sandstone and siltstone sandstone Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 3.0 inches Available water capacity: Mainly 2.0 inches Additional Components Additional Components Boxwell and similar soils: 3 percent Marmarth and similar soils: 3 percent Delpoint and similar soils: 2 percent Reedpoint and similar soils: 3 percent Marmarth and similar soils: 2 percent Cabbart and similar soils: 2 percent Yawdim and similar soils: 2 percent Delpoint and similar soils: 1 percent Ethridge and similar soils: 1 percent Yawdim and similar soils: 1 percent Management Management For management information about this map unit, For management information about this map unit, see appropriate sections in Part II of this publication. see appropriate sections in Part II of this publication. Sweet Grass County Area, Montana—Part I 183

130D—Tanna-Hinterland clay loams, 131D—Reedpoint very channery loam, 8 to 15 percent slopes 2 to 15 percent slopes

Setting Setting Elevation: 3,750 to 5,200 feet Field investigation intensity: Order 2 Mean annual precipitation: 10 to 14 inches Elevation: 3,750 to 5,200 feet Frost-free period: 95 to 125 days Mean annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Major Component Description Tanna and similar soils Major Component Description Composition: 50 percent Geomorphic description: Plain and swale Reedpoint and similar soils Slope: 8 to 15 percent Composition: 85 percent Elevation: 3,750 to 5,200 feet Geomorphic description: Plain and structural bench Effective annual precipitation: 10 to 14 inches Slope: 2 to 15 percent Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Surface layer texture: Clay loam Effective annual precipitation: 10 to 14 inches Depth to bedrock (paralithic): 20 to 40 inches Frost-free period: 95 to 125 days Drainage class: Well drained Surface layer texture: Very channery loam Parent material: Clayey residuum weathered from Depth to bedrock (lithic): 4 to 10 inches sandstone and shale Drainage class: Well drained Native plant cover type: Rangeland Parent material: Residuum weathered from Available water capacity: Mainly 4.2 inches sandstone Native plant cover type: Rangeland Hinterland and similar soils Available water capacity: Mainly 0.4 inches Composition: 40 percent Geomorphic description: Knoll and plain Additional Components Slope: 8 to 15 percent Elevation: 3,750 to 5,200 feet Hinterland and similar soils: 6 percent Effective annual precipitation: 10 to 14 inches Rock outcrop: 4 percent Frost-free period: 95 to 125 days Tanna and similar soils: 3 percent Surface layer texture: Clay loam Cabbart and similar soils: 1 percent Depth to bedrock (lithic): 10 to 20 inches Rentsac and similar soils: 1 percent Drainage class: Well drained Parent material: Residuum weathered from Management sandstone For management information about this map unit, Native plant cover type: Rangeland see appropriate sections in Part II of this publication. Available water capacity: Mainly 2.0 inches Additional Components Cabbart and similar soils: 3 percent 131F—Reedpoint very channery loam, Marmarth and similar soils: 3 percent 15 to 60 percent slopes Reedpoint and similar soils: 2 percent Delpoint and similar soils: 1 percent Setting Yawdim and similar soils: 1 percent Field investigation intensity: Order 2 Management Elevation: 3,750 to 5,200 feet For management information about this map unit, Mean annual precipitation: 10 to 14 inches see appropriate sections in Part II of this publication. Frost-free period: 95 to 125 days 184 Soil Survey

Major Component Description Additional Components Reedpoint and similar soils Lonna and similar soils: 4 percent Composition: 85 percent Delpoint and similar soils: 3 percent Geomorphic description: Havre and similar soils: 3 percent • Nose slope summit on escarpment Kobase and similar soils: 3 percent • Nose slope shoulder on escarpment Kremlin and similar soils: 2 percent Slope: 15 to 60 percent Management Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches For management information about this map unit, Frost-free period: 95 to 125 days see appropriate sections in Part II of this publication. Surface layer texture: Very channery loam Depth to bedrock (lithic): 4 to 10 inches Drainage class: Well drained 134C—Yamacall loam, 4 to 8 percent Parent material: Residuum weathered from slopes sandstone Native plant cover type: Rangeland Setting Available water capacity: Mainly 0.4 inches Elevation: 3,750 to 5,200 feet Additional Components Mean annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Rentsac and similar soils: 6 percent Rock outcrop: 5 percent Major Component Description Cabbart and similar soils: 2 percent Yamacall and similar soils Tanna and similar soils: 2 percent Composition: 85 percent Management Geomorphic description: Fan Slope: 4 to 8 percent For management information about this map unit, Elevation: 3,750 to 5,200 feet see appropriate sections in Part II of this publication. Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Surface layer texture: Loam 134B—Yamacall loam, 1 to 4 percent Drainage class: Well drained slopes Parent material: Loamy alluvium Native plant cover type: Rangeland Setting Available water capacity: Mainly 9.6 inches Elevation: 3,750 to 5,200 feet Additional Components Mean annual precipitation: 10 to 14 inches Yamacall and similar soils: 9 percent Frost-free period: 95 to 125 days Kremlin and similar soils: 6 percent Major Component Description Management Yamacall and similar soils For management information about this map unit, Composition: 85 percent see appropriate sections in Part II of this publication. Geomorphic description: Tread on stream terrace Slope: 1 to 4 percent Elevation: 3,750 to 5,200 feet 134D—Yamacall loam, 8 to 15 percent Effective annual precipitation: 10 to 14 inches slopes Frost-free period: 95 to 125 days Surface layer texture: Loam Setting Drainage class: Well drained Parent material: Loamy alluvium Elevation: 3,750 to 5,200 feet Native plant cover type: Rangeland Mean annual precipitation: 10 to 14 inches Available water capacity: Mainly 9.6 inches Frost-free period: 95 to 125 days Sweet Grass County Area, Montana—Part I 185

Major Component Description Macar and similar soils: 0 to 2 percent Yamacall and similar soils: 0 to 2 percent Yamacall and similar soils Composition: 85 percent Management Geomorphic description: Fan For management information about this map unit, Slope: 8 to 15 percent see appropriate sections in Part II of this publication. Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Surface layer texture: Loam 138D—Cabbart-Megonot-Kobase clay Drainage class: Well drained loams, 2 to 15 percent slopes Parent material: Loamy alluvium Native plant cover type: Rangeland Setting Available water capacity: Mainly 9.6 inches Elevation: 3,750 to 5,200 feet Additional Components Mean annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Yamacall and similar soils: 9 percent Kremlin and similar soils: 6 percent Major Component Description Management Cabbart and similar soils Composition: 40 percent For management information about this map unit, Geomorphic description: Knoll and plain see appropriate sections in Part II of this publication. Slope: 2 to 15 percent Elevation: 3,750 to 5,200 feet 135A—Fairway loam, 0 to 2 percent Effective annual precipitation: 10 to 14 inches slopes Frost-free period: 95 to 125 days Surface layer texture: Loam Depth to bedrock (paralithic): 10 to 20 inches Setting Drainage class: Well drained Field investigation intensity: Order 2 Parent material: Loamy residuum weathered from Elevation: 3,750 to 6,000 feet sandstone and siltstone Mean annual precipitation: 10 to 19 inches Native plant cover type: Rangeland Frost-free period: 85 to 125 days Available water capacity: Mainly 3.0 inches Major Component Description Megonot and similar soils Fairway and similar soils Composition: 30 percent Composition: 85 percent Geomorphic description: Plain and swale Geomorphic description: Flood plain Slope: 2 to 15 percent Slope: 0 to 2 percent Elevation: 3,750 to 5,200 feet Elevation: 3,750 to 6,000 feet Effective annual precipitation: 10 to 14 inches Effective annual precipitation: 10 to 19 inches Frost-free period: 95 to 125 days Frost-free period: 85 to 125 days Surface layer texture: Clay loam Surface layer texture: Loam Depth to bedrock (paralithic): 20 to 40 inches Drainage class: Somewhat poorly drained Drainage class: Well drained Parent material: Loamy alluvium Parent material: Clayey residuum weathered from Native plant cover type: Rangeland shale Flooding: Rare Native plant cover type: Rangeland Water table: Present Available water capacity: Mainly 3.9 inches Available water capacity: Mainly 9.1 inches Kobase and similar soils Additional Components Composition: 20 percent Meadowcreek and similar soils: 5 percent Geomorphic description: Plain and swale Soapcreek and similar soils: 4 percent Slope: 2 to 15 percent Swampcreek and similar soils: 4 percent Elevation: 3,750 to 5,200 feet 186 Soil Survey

Effective annual precipitation: 10 to 14 inches Native plant cover type: Rangeland Frost-free period: 95 to 125 days Available water capacity: Mainly 4.6 inches Surface layer texture: Clay loam Additional Components Drainage class: Well drained Parent material: Clayey alluvium weathered from Boxwell and similar soils: 4 percent shale and siltstone Reedpoint and similar soils: 2 percent Native plant cover type: Rangeland Rentsac and similar soils: 2 percent Available water capacity: Mainly 9.4 inches Yamacall and similar soils: 2 percent Additional Components Management Delpoint and similar soils: 5 percent For management information about this map unit, Yawdim and similar soils: 5 percent see appropriate sections in Part II of this publication. Management For management information about this map unit, 139D—Cabbart-Delpoint loams, see appropriate sections in Part II of this publication. 8 to 15 percent slopes

139C—Cabbart-Delpoint loams, Setting 2 to 8 percent slopes Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Setting Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Major Component Description Frost-free period: 95 to 125 days Cabbart and similar soils Major Component Description Composition: 50 percent Cabbart and similar soils Geomorphic description: Knoll and plain Composition: 50 percent Slope: 8 to 15 percent Geomorphic description: Knoll and plain Elevation: 3,750 to 5,200 feet Slope: 2 to 8 percent Effective annual precipitation: 10 to 14 inches Elevation: 3,750 to 5,200 feet Frost-free period: 95 to 125 days Effective annual precipitation: 10 to 14 inches Surface layer texture: Loam Frost-free period: 95 to 125 days Depth to bedrock (paralithic): 10 to 20 inches Surface layer texture: Loam Drainage class: Well drained Depth to bedrock (paralithic): 10 to 20 inches Parent material: Loamy residuum weathered from Drainage class: Well drained sandstone and siltstone Parent material: Loamy residuum weathered from Native plant cover type: Rangeland sandstone and siltstone Available water capacity: Mainly 3.0 inches Native plant cover type: Rangeland Available water capacity: Mainly 3.0 inches Delpoint and similar soils Composition: 40 percent Delpoint and similar soils Geomorphic description: Plain and swale Composition: 40 percent Slope: 8 to 15 percent Geomorphic description: Plain and swale Elevation: 3,750 to 5,200 feet Slope: 2 to 8 percent Effective annual precipitation: 10 to 14 inches Elevation: 3,750 to 5,200 feet Frost-free period: 95 to 125 days Effective annual precipitation: 10 to 14 inches Surface layer texture: Loam Frost-free period: 95 to 125 days Depth to bedrock (paralithic): 20 to 40 inches Surface layer texture: Loam Drainage class: Well drained Depth to bedrock (paralithic): 20 to 40 inches Parent material: Loamy residuum weathered from Drainage class: Well drained sandstone and siltstone Parent material: Loamy residuum weathered from Native plant cover type: Rangeland sandstone and siltstone Available water capacity: Mainly 4.6 inches Sweet Grass County Area, Montana—Part I 187

Additional Components Native plant cover type: Rangeland Available water capacity: Mainly 3.8 inches Boxwell and similar soils: 4 percent Reedpoint and similar soils: 2 percent Additional Components Rentsac and similar soils: 2 percent Rentsac and similar soils: 3 percent Yamacall and similar soils: 2 percent Yamacall and similar soils: 3 percent Management Reedpoint and similar soils: 2 percent Rock outcrop: 2 percent For management information about this map unit, see appropriate sections in Part II of this publication. Management For management information about this map unit, see appropriate sections in Part II of this publication. 139E—Cabbart-Delpoint loams, 15 to 35 percent slopes 140F—Yawdim-Rentsac complex, Setting 15 to 60 percent slopes Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Setting Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Major Component Description Mean annual precipitation: 10 to 14 inches Cabbart and similar soils Frost-free period: 95 to 125 days Composition: 50 percent Major Component Description Geomorphic description: • Nose slope summit on hill Yawdim and similar soils • Nose slope backslope on hill Composition: 50 percent • Side slope backslope on hill Geomorphic description: Slope: 15 to 35 percent • Nose slope summit on escarpment Elevation: 3,750 to 5,200 feet • Nose slope shoulder on escarpment Effective annual precipitation: 10 to 14 inches • Side slope shoulder on escarpment Frost-free period: 95 to 125 days Slope: 15 to 60 percent Surface layer texture: Loam Elevation: 3,750 to 5,200 feet Depth to bedrock (paralithic): 10 to 20 inches Effective annual precipitation: 10 to 14 inches Drainage class: Well drained Frost-free period: 95 to 125 days Parent material: Loamy residuum weathered from Surface layer texture: Clay loam sandstone and siltstone Depth to bedrock (paralithic): 10 to 20 inches Native plant cover type: Rangeland Drainage class: Well drained Available water capacity: Mainly 3.0 inches Parent material: Clayey residuum weathered from calcareous shale Delpoint and similar soils Native plant cover type: Rangeland Composition: 40 percent Available water capacity: Mainly 2.0 inches Geomorphic description: • Base slope backslope on hill Rentsac and similar soils • Base slope footslope on hill Composition: 40 percent • Side slope backslope on hill Geomorphic description: Slope: 15 to 35 percent • Nose slope summit on escarpment Elevation: 3,750 to 5,200 feet • Nose slope shoulder on escarpment Effective annual precipitation: 10 to 14 inches Slope: 15 to 60 percent Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Surface layer texture: Loam Effective annual precipitation: 10 to 14 inches Depth to bedrock (paralithic): 20 to 40 inches Frost-free period: 95 to 125 days Drainage class: Well drained Surface layer texture: Channery loam Parent material: Loamy residuum weathered from Depth to bedrock (lithic): 10 to 20 inches sandstone and siltstone Drainage class: Well drained 188 Soil Survey

Parent material: Residuum weathered from Native plant cover type: Rangeland calcareous sandstone Available water capacity: Mainly 3.0 inches Native plant cover type: Rangeland Additional Components Available water capacity: Mainly 1.4 inches Delpoint and similar soils: 2 percent Additional Components Hinterland and similar soils: 2 percent Rock outcrop: 4 percent Rentsac and similar soils: 2 percent Cabbart and similar soils: 2 percent Tanna and similar soils: 2 percent Delpoint and similar soils: 2 percent Yawdim and similar soils: 2 percent Megonot and similar soils: 2 percent Management Management For management information about this map unit, For management information about this map unit, see appropriate sections in Part II of this publication. see appropriate sections in Part II of this publication. 141D—Marmarth-Cabbart loams, 141C—Marmarth-Cabbart loams, 8 to 15 percent slopes 2 to 8 percent slopes Setting Field investigation intensity: Order 2 Setting Elevation: 3,750 to 5,200 feet Field investigation intensity: Order 2 Mean annual precipitation: 10 to 14 inches Elevation: 3,750 to 5,200 feet Frost-free period: 95 to 125 days Mean annual precipitation: 10 to 14 inches Major Component Description Frost-free period: 95 to 125 days Marmarth and similar soils Major Component Description Composition: 50 percent Marmarth and similar soils Geomorphic description: Plain and swale Composition: 50 percent Slope: 8 to 15 percent Geomorphic description: Plain and swale Elevation: 3,750 to 5,200 feet Slope: 2 to 8 percent Effective annual precipitation: 10 to 14 inches Elevation: 3,750 to 5,200 feet Frost-free period: 95 to 125 days Effective annual precipitation: 10 to 14 inches Surface layer texture: Loam Frost-free period: 95 to 125 days Depth to bedrock (paralithic): 20 to 40 inches Surface layer texture: Loam Drainage class: Well drained Depth to bedrock (paralithic): 20 to 40 inches Parent material: Loamy residuum weathered from Drainage class: Well drained sandstone and siltstone Parent material: Loamy residuum weathered from Native plant cover type: Rangeland sandstone and siltstone Available water capacity: Mainly 5.6 inches Native plant cover type: Rangeland Available water capacity: Mainly 5.6 inches Cabbart and similar soils Composition: 40 percent Cabbart and similar soils Geomorphic description: Knoll and plain Composition: 40 percent Slope: 8 to 15 percent Geomorphic description: Knoll and plain Elevation: 3,750 to 5,200 feet Slope: 2 to 8 percent Effective annual precipitation: 10 to 14 inches Elevation: 3,750 to 5,200 feet Frost-free period: 95 to 125 days Effective annual precipitation: 10 to 14 inches Surface layer texture: Loam Frost-free period: 95 to 125 days Depth to bedrock (paralithic): 10 to 20 inches Surface layer texture: Loam Drainage class: Well drained Depth to bedrock (paralithic): 10 to 20 inches Parent material: Loamy residuum weathered from Drainage class: Well drained sandstone and siltstone Parent material: Loamy residuum weathered from Native plant cover type: Rangeland sandstone and siltstone Available water capacity: Mainly 3.0 inches Sweet Grass County Area, Montana—Part I 189

Additional Components Major Component Description Delpoint and similar soils: 2 percent Evanston and similar soils Reedpoint and similar soils: 2 percent Composition: 85 percent Rentsac and similar soils: 2 percent Geomorphic description: Tread on terrace Tanna and similar soils: 2 percent Slope: 0 to 4 percent Yawdim and similar soils: 2 percent Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Management Frost-free period: 95 to 125 days For management information about this map unit, Surface layer texture: Loam see appropriate sections in Part II of this publication. Drainage class: Well drained Parent material: Loamy alluvium Native plant cover type: Rangeland 142C—Tanna clay loam, 2 to 8 percent Available water capacity: Mainly 9.9 inches slopes Additional Components Setting Ethridge and similar soils: 5 percent Elevation: 3,750 to 5,200 feet Kremlin and similar soils: 5 percent Mean annual precipitation: 10 to 14 inches Marmarth and similar soils: 3 percent Frost-free period: 95 to 125 days Tanna and similar soils: 2 percent Major Component Description Management Tanna and similar soils Composition: 85 percent For management information about this map unit, Geomorphic description: Plain and swale see appropriate sections in Part II of this publication. Slope: 2 to 8 percent Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches 144C—Evanston loam, 4 to 8 percent Frost-free period: 95 to 125 days slopes Surface layer texture: Clay loam Depth to bedrock (paralithic): 20 to 40 inches Drainage class: Well drained Setting Parent material: Clayey residuum weathered from Elevation: 3,750 to 5,200 feet sandstone and shale Mean annual precipitation: 10 to 14 inches Native plant cover type: Rangeland Frost-free period: 95 to 125 days Available water capacity: Mainly 4.2 inches Additional Components Major Component Description Ethridge and similar soils: 8 percent Evanston and similar soils Marmarth and similar soils: 4 percent Composition: 85 percent Cabbart and similar soils: 3 percent Geomorphic description: Microlow on fan Management Slope: 4 to 8 percent Elevation: 3,750 to 5,200 feet For management information about this map unit, Effective annual precipitation: 10 to 14 inches see appropriate sections in Part II of this publication. Frost-free period: 95 to 125 days Surface layer texture: Loam 144B—Evanston loam, 0 to 4 percent Drainage class: Well drained slopes Parent material: Loamy alluvium Native plant cover type: Rangeland Available water capacity: Mainly 9.9 inches Setting Additional Components Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Ethridge and similar soils: 8 percent Frost-free period: 95 to 125 days Kremlin and similar soils: 7 percent 190 Soil Survey

Management Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days For management information about this map unit, Surface layer texture: Loam see appropriate sections in Part II of this publication. Depth to bedrock (paralithic): 20 to 40 inches Drainage class: Well drained 144D—Evanston loam, 8 to 15 percent Parent material: Loamy residuum weathered from slopes sandstone and siltstone Native plant cover type: Rangeland Available water capacity: Mainly 4.9 inches Setting Elevation: 3,750 to 5,200 feet Cabbart and similar soils Mean annual precipitation: 10 to 14 inches Composition: 40 percent Frost-free period: 95 to 125 days Geomorphic description: Knoll and plain Slope: 2 to 8 percent Major Component Description Elevation: 3,750 to 5,200 feet Evanston and similar soils Effective annual precipitation: 10 to 14 inches Composition: 85 percent Frost-free period: 95 to 125 days Geomorphic description: Microlow on fan Surface layer texture: Loam Slope: 8 to 15 percent Depth to bedrock (paralithic): 10 to 20 inches Elevation: 3,750 to 5,200 feet Drainage class: Well drained Effective annual precipitation: 10 to 14 inches Parent material: Loamy residuum weathered from Frost-free period: 95 to 125 days sandstone and siltstone Surface layer texture: Loam Native plant cover type: Rangeland Drainage class: Well drained Available water capacity: Mainly 3.0 inches Parent material: Loamy alluvium Additional Components Native plant cover type: Rangeland Available water capacity: Mainly 9.9 inches Delpoint and similar soils: 3 percent Tanna and similar soils: 3 percent Additional Components Marmarth and similar soils: 2 percent Ethridge and similar soils: 8 percent Rentsac and similar soils: 2 percent Kremlin and similar soils: 7 percent Management Management For management information about this map unit, For management information about this map unit, see appropriate sections in Part II of this publication. see appropriate sections in Part II of this publication.

145C—Boxwell, calcareous-Cabbart 146B—Ethridge clay loam, 1 to 4 percent loams, 2 to 8 percent slopes slopes

Setting Setting Field investigation intensity: Order 2 Elevation: 3,750 to 5,200 feet Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Mean annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Frost-free period: 95 to 125 days Major Component Description Major Component Description Ethridge and similar soils Boxwell and similar soils Composition: 85 percent Composition: 50 percent Geomorphic description: Tread on terrace Geomorphic description: Plain and swale Slope: 1 to 4 percent Slope: 2 to 8 percent Elevation: 3,750 to 5,200 feet Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Sweet Grass County Area, Montana—Part I 191

Frost-free period: 95 to 125 days 147B—Kremlin loam, 0 to 4 percent Surface layer texture: Clay loam slopes Drainage class: Well drained Parent material: Clayey alluvium Setting Native plant cover type: Rangeland Available water capacity: Mainly 9.7 inches Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Additional Components Frost-free period: 95 to 125 days Evanston and similar soils: 5 percent Major Component Description Richey and similar soils: 4 percent Creed and similar soils: 3 percent Kremlin and similar soils Kremlin and similar soils: 2 percent Composition: 85 percent Gerdrum and similar soils: 1 percent Geomorphic description: Tread on stream terrace Slope: 0 to 4 percent Management Elevation: 3,750 to 5,200 feet For management information about this map unit, Effective annual precipitation: 10 to 14 inches see appropriate sections in Part II of this publication. Frost-free period: 95 to 125 days Surface layer texture: Loam Drainage class: Well drained 146C—Ethridge clay loam, 4 to 8 percent Parent material: Loamy alluvium slopes Native plant cover type: Rangeland Available water capacity: Mainly 10.3 inches Additional Components Setting Evanston and similar soils: 4 percent Elevation: 3,750 to 5,200 feet Yamacall and similar soils: 4 percent Mean annual precipitation: 10 to 14 inches Delpoint and similar soils: 2 percent Frost-free period: 95 to 125 days Ethridge and similar soils: 2 percent Major Component Description Tanna and similar soils: 2 percent Cabbart and similar soils: 1 percent Ethridge and similar soils Composition: 87 percent Management Geomorphic description: Fan and swale For management information about this map unit, Slope: 4 to 8 percent see appropriate sections in Part II of this publication. Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days 147C—Kremlin loam, 4 to 8 percent Surface layer texture: Clay loam slopes Drainage class: Well drained Parent material: Clayey alluvium Setting Native plant cover type: Rangeland Available water capacity: Mainly 9.7 inches Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Additional Components Frost-free period: 95 to 125 days Tanna and similar soils: 6 percent Major Component Description Note: This soil exists on the upper one third of the landform. Kremlin and similar soils Evanston and similar soils: 5 percent Composition: 85 percent Creed and similar soils: 2 percent Geomorphic description: Fan Slope: 4 to 8 percent Management Elevation: 3,750 to 5,200 feet For management information about this map unit, Effective annual precipitation: 10 to 14 inches see appropriate sections in Part II of this publication. Frost-free period: 95 to 125 days 192 Soil Survey

Surface layer texture: Loam 148E—Cabbart-Cambeth complex, Drainage class: Well drained 4 to 35 percent slopes Parent material: Loamy alluvium Native plant cover type: Rangeland Setting Available water capacity: Mainly 10.3 inches Elevation: 3,750 to 5,200 feet Additional Components Mean annual precipitation: 10 to 14 inches Yamacall and similar soils: 7 percent Frost-free period: 95 to 125 days Evanston and similar soils: 4 percent Kremlin and similar soils: 4 percent Major Component Description Management Cabbart and similar soils Composition: 50 percent For management information about this map unit, Geomorphic description: see appropriate sections in Part II of this publication. • Nose slope summit on hill • Nose slope backslope on hill 147D—Kremlin loam, 8 to 15 percent • Side slope backslope on hill slopes Slope: 4 to 35 percent Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Setting Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Surface layer texture: Loam Mean annual precipitation: 10 to 14 inches Depth to bedrock (paralithic): 10 to 20 inches Frost-free period: 95 to 125 days Drainage class: Well drained Parent material: Loamy residuum weathered from Major Component Description sandstone and siltstone Kremlin and similar soils Native plant cover type: Rangeland Composition: 88 percent Available water capacity: Mainly 3.0 inches Geomorphic description: Fan Slope: 8 to 15 percent Cambeth and similar soils Elevation: 3,750 to 5,200 feet Composition: 40 percent Effective annual precipitation: 10 to 14 inches Geomorphic description: Base slope footslope on hill Frost-free period: 95 to 125 days Slope: 4 to 15 percent Surface layer texture: Loam Elevation: 3,750 to 5,200 feet Drainage class: Well drained Effective annual precipitation: 10 to 14 inches Parent material: Loamy alluvium Frost-free period: 95 to 125 days Native plant cover type: Rangeland Surface layer texture: Silt loam Available water capacity: Mainly 10.3 inches Depth to bedrock (paralithic): 20 to 40 inches Drainage class: Well drained Additional Components Parent material: Silty residuum weathered from Yamacall and similar soils: 5 percent sandstone and siltstone Ethridge and similar soils: 4 percent Native plant cover type: Rangeland Evanston and similar soils: 3 percent Available water capacity: Mainly 6.2 inches Management Additional Components For management information about this map unit, Delpoint and similar soils: 5 percent see appropriate sections in Part II of this publication. Tanna and similar soils: 5 percent Sweet Grass County Area, Montana—Part I 193

Management Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches For management information about this map unit, Frost-free period: 95 to 125 days see appropriate sections in Part II of this publication. Surface layer texture: Clay loam Drainage class: Well drained 150C—Kobase clay loam, 2 to 8 percent Parent material: Clayey alluvium weathered from slopes shale and siltstone Native plant cover type: Rangeland Available water capacity: Mainly 9.4 inches Setting Additional Components Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Megonot and similar soils: 4 percent Frost-free period: 95 to 125 days Yamacall and similar soils: 4 percent Richey and similar soils: 3 percent Major Component Description Delpoint and similar soils: 2 percent Kobase and similar soils Ethridge and similar soils: 2 percent Composition: 85 percent Management Geomorphic description: Plain and swale Slope: 2 to 8 percent For management information about this map unit, Elevation: 3,750 to 5,200 feet see appropriate sections in Part II of this publication. Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Surface layer texture: Clay loam 151C—Cabbart-Boxwell loams, Drainage class: Well drained 2 to 8 percent slopes Parent material: Clayey alluvium weathered from shale and siltstone Setting Native plant cover type: Rangeland Elevation: 3,750 to 5,200 feet Available water capacity: Mainly 9.4 inches Mean annual precipitation: 10 to 14 inches Additional Components Frost-free period: 95 to 125 days Ethridge and similar soils: 4 percent Major Component Description Megonot and similar soils: 4 percent Cabbart and similar soils Yamacall and similar soils: 3 percent Composition: 50 percent Cabbart and similar soils: 2 percent Geomorphic description: Knoll and plain Yawdim and similar soils: 2 percent Slope: 2 to 8 percent Management Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches For management information about this map unit, Frost-free period: 95 to 125 days see appropriate sections in Part II of this publication. Surface layer texture: Loam Depth to bedrock (paralithic): 10 to 20 inches 150D—Kobase clay loam, 8 to 15 percent Drainage class: Well drained slopes Parent material: Loamy residuum weathered from sandstone and siltstone Native plant cover type: Rangeland Setting Available water capacity: Mainly 3.0 inches Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Boxwell and similar soils Frost-free period: 95 to 125 days Composition: 40 percent Geomorphic description: Plain and swale Major Component Description Slope: 2 to 8 percent Kobase and similar soils Elevation: 3,750 to 5,200 feet Composition: 85 percent Effective annual precipitation: 10 to 14 inches Geomorphic description: Plain and swale Frost-free period: 95 to 125 days Slope: 8 to 15 percent Surface layer texture: Loam 194 Soil Survey

Depth to bedrock (paralithic): 20 to 40 inches Drainage class: Well drained Drainage class: Well drained Parent material: Loamy residuum weathered from Parent material: Loamy residuum weathered from sandstone and siltstone sandstone and siltstone Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 5.0 inches Available water capacity: Mainly 5.0 inches Additional Components Additional Components Delpoint and similar soils: 3 percent Delpoint and similar soils: 3 percent Tanna and similar soils: 3 percent Kremlin and similar soils: 2 percent Kremlin and similar soils: 2 percent Marmarth and similar soils: 2 percent Rock outcrop: 2 percent Megonot and similar soils: 2 percent Management Hinterland and similar soils: 1 percent For management information about this map unit, Management see appropriate sections in Part II of this publication. For management information about this map unit, see appropriate sections in Part II of this publication. 153C—Ethridge-Reedpoint complex, 2 to 8 percent slopes 151D—Cabbart-Boxwell loams, 8 to 15 percent slopes Setting Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Setting Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Major Component Description Mean annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Ethridge and similar soils Composition: 50 percent Major Component Description Geomorphic description: Knoll and plain Cabbart and similar soils Slope: 2 to 8 percent Composition: 50 percent Elevation: 3,750 to 5,200 feet Geomorphic description: Knoll and plain Effective annual precipitation: 10 to 14 inches Slope: 8 to 15 percent Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Surface layer texture: Clay loam Effective annual precipitation: 10 to 14 inches Drainage class: Well drained Frost-free period: 95 to 125 days Parent material: Clayey alluvium Surface layer texture: Loam Native plant cover type: Rangeland Depth to bedrock (paralithic): 10 to 20 inches Available water capacity: Mainly 9.7 inches Drainage class: Well drained Parent material: Loamy residuum weathered from Reedpoint and similar soils sandstone and siltstone Composition: 40 percent Native plant cover type: Rangeland Geomorphic description: Plain and swale Available water capacity: Mainly 3.0 inches Slope: 2 to 8 percent Elevation: 3,750 to 5,200 feet Boxwell and similar soils Effective annual precipitation: 10 to 14 inches Composition: 40 percent Frost-free period: 95 to 125 days Geomorphic description: Plain and swale Surface layer texture: Very channery loam Slope: 8 to 15 percent Depth to bedrock (lithic): 4 to 10 inches Elevation: 3,750 to 5,200 feet Drainage class: Well drained Effective annual precipitation: 10 to 14 inches Parent material: Residuum weathered from Frost-free period: 95 to 125 days sandstone Surface layer texture: Loam Native plant cover type: Rangeland Depth to bedrock (paralithic): 20 to 40 inches Available water capacity: Mainly 0.4 inches Sweet Grass County Area, Montana—Part I 195

Additional Components Tanna and similar soils: 2 percent Rock outcrop: 1 percent Dimmick and similar soils: 3 percent Kremlin and similar soils: 3 percent Management Hinterland and similar soils: 2 percent For management information about this map unit, Tanna and similar soils: 2 percent see appropriate sections in Part II of this publication. Management For management information about this map unit, see appropriate sections in Part II of this publication. 154E—Evanston-Reedpoint complex, 8 to 35 percent slopes

153D—Ethridge-Reedpoint complex, Setting 8 to 15 percent slopes Field investigation intensity: Order 2 Elevation: 3,750 to 5,200 feet Setting Mean annual precipitation: 10 to 14 inches Field investigation intensity: Order 2 Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Major Component Description Mean annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Evanston and similar soils Composition: 45 percent Major Component Description Geomorphic description: Base slope toeslope on hill Ethridge and similar soils Slope: 8 to 35 percent Composition: 50 percent Elevation: 3,750 to 5,200 feet Geomorphic description: Plain and swale Effective annual precipitation: 10 to 14 inches Slope: 8 to 15 percent Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Surface layer texture: Loam Effective annual precipitation: 10 to 14 inches Drainage class: Well drained Frost-free period: 95 to 125 days Parent material: Loamy alluvium Surface layer texture: Clay loam Native plant cover type: Rangeland Drainage class: Well drained Available water capacity: Mainly 9.9 inches Parent material: Clayey alluvium Native plant cover type: Rangeland Reedpoint and similar soils Available water capacity: Mainly 9.7 inches Composition: 40 percent Geomorphic description: Reedpoint and similar soils • Nose slope summit on hill Composition: 40 percent • Nose slope shoulder on hill Geomorphic description: Knoll and plain Slope: 8 to 35 percent Slope: 8 to 15 percent Elevation: 3,750 to 5,200 feet Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Frost-free period: 95 to 125 days Surface layer texture: Very channery loam Surface layer texture: Very channery loam Depth to bedrock (lithic): 4 to 10 inches Depth to bedrock (lithic): 4 to 10 inches Drainage class: Well drained Drainage class: Well drained Parent material: Residuum weathered from Parent material: Residuum weathered from sandstone sandstone Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 0.4 inches Available water capacity: Mainly 0.4 inches Additional Components Additional Components Marmarth and similar soils: 5 percent Dimmick and similar soils: 3 percent Delpoint and similar soils: 3 percent Hinterland and similar soils: 2 percent Hinterland and similar soils: 2 percent Kremlin and similar soils: 2 percent Tanna and similar soils: 2 percent 196 Soil Survey

Yamacall and similar soils: 2 percent Additional Components Rock outcrop: 1 percent Reedpoint and similar soils: 3 percent Management Yamacall and similar soils: 3 percent Yawdim and similar soils: 2 percent For management information about this map unit, Rentsac and similar soils: 1 percent see appropriate sections in Part II of this publication. Rock outcrop: 1 percent Management 155E—Cabbart-Delpoint loams, moist, 15 to 35 percent slopes For management information about this map unit, see appropriate sections in Part II of this publication. Setting Elevation: 3,750 to 5,200 feet 156C—Twilight-Blacksheep fine sandy Mean annual precipitation: 10 to 14 inches loams, 2 to 8 percent slopes Frost-free period: 95 to 125 days Major Component Description Setting Cabbart and similar soils Elevation: 3,750 to 5,200 feet Composition: 50 percent Mean annual precipitation: 10 to 14 inches Geomorphic description: Frost-free period: 95 to 125 days • Nose slope summit on hill • Nose slope backslope on hill Major Component Description • Side slope backslope on hill Slope: 15 to 35 percent Twilight and similar soils Elevation: 3,750 to 5,200 feet Composition: 50 percent Effective annual precipitation: 10 to 14 inches Geomorphic description: Plain and swale Frost-free period: 95 to 125 days Slope: 2 to 8 percent Surface layer texture: Loam Elevation: 3,750 to 5,200 feet Depth to bedrock (paralithic): 10 to 20 inches Effective annual precipitation: 10 to 14 inches Drainage class: Well drained Frost-free period: 95 to 125 days Parent material: Loamy residuum weathered from Surface layer texture: Fine sandy loam sandstone and siltstone Depth to bedrock (paralithic): 20 to 40 inches Native plant cover type: Forestland Drainage class: Well drained Available water capacity: Mainly 3.0 inches Parent material: Sandy residuum weathered from calcareous sandstone Delpoint and similar soils Native plant cover type: Rangeland Composition: 40 percent Available water capacity: Mainly 3.8 inches Geomorphic description: • Base slope backslope on hill Blacksheep and similar soils • Base slope footslope on hill Composition: 40 percent • Side slope backslope on hill Geomorphic description: Knoll and plain Slope: 15 to 35 percent Slope: 2 to 8 percent Elevation: 3,750 to 5,200 feet Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Frost-free period: 95 to 125 days Surface layer texture: Loam Surface layer texture: Fine sandy loam Depth to bedrock (paralithic): 20 to 40 inches Depth to bedrock (paralithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained Parent material: Loamy residuum weathered from Parent material: Sandy residuum weathered from sandstone and siltstone calcareous sandstone Native plant cover type: Forestland Native plant cover type: Rangeland Available water capacity: Mainly 3.8 inches Available water capacity: Mainly 2.2 inches Sweet Grass County Area, Montana—Part I 197

Additional Components Parent material: Loamy residuum weathered from sandstone and siltstone Cabbart and similar soils: 3 percent Native plant cover type: Rangeland Delpoint and similar soils: 3 percent Available water capacity: Mainly 3.8 inches Chinook and similar soils: 2 percent Reedpoint and similar soils: 2 percent Rock outcrop Management Composition: 15 percent Definition: Rock outcrop consists mainly of areas of For management information about this map unit, exposed hard bedrock. see appropriate sections in Part II of this publication. Geomorphic description: Escarpment Additional Components 157F—Cabbart, moist-Delpoint-Rock outcrop complex, 15 to 60 percent Reedpoint and similar soils: 3 percent slopes Yamacall and similar soils: 3 percent Yawdim and similar soils: 3 percent Tanna and similar soils: 1 percent Setting Management Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches For management information about this map unit, Frost-free period: 95 to 125 days see appropriate sections in Part II of this publication. Major Component Description Cabbart and similar soils 159A—Marcott cobbly clay loam, Composition: 60 percent 0 to 2 percent slopes Geomorphic description: • Nose slope summit on escarpment Setting • Nose slope backslope on escarpment • Side slope backslope on escarpment Elevation: 3,750 to 4,300 feet Slope: 15 to 60 percent Mean annual precipitation: 10 to 14 inches Elevation: 3,750 to 5,200 feet Frost-free period: 95 to 130 days Effective annual precipitation: 10 to 14 inches Major Component Description Frost-free period: 95 to 125 days Surface layer texture: Loam Marcott and similar soils Depth to bedrock (paralithic): 10 to 20 inches Composition: 85 percent Drainage class: Well drained Geomorphic description: Flood plain Parent material: Loamy residuum weathered from Slope: 0 to 2 percent sandstone and siltstone Elevation: 3,750 to 4,300 feet Native plant cover type: Forestland Effective annual precipitation: 10 to 14 inches Available water capacity: Mainly 3.0 inches Frost-free period: 95 to 130 days Surface layer texture: Cobbly clay loam Delpoint and similar soils Drainage class: Somewhat poorly drained Composition: 15 percent Parent material: Clayey alluvium Geomorphic description: Native plant cover type: Rangeland • Base slope backslope on escarpment Flooding: Rare • Base slope footslope on escarpment Water table: Present • Side slope backslope on escarpment Salt affected: Saline within 30 inches Slope: 15 to 60 percent Sodium affected: Sodic within 30 inches Elevation: 3,750 to 5,200 feet Available water capacity: Mainly 6.7 inches Effective annual precipitation: 10 to 14 inches Additional Components Frost-free period: 95 to 125 days Surface layer texture: Loam Beaverell and similar soils: 5 percent Depth to bedrock (paralithic): 20 to 40 inches Larry and similar soils: 5 percent Drainage class: Well drained Swampcreek and similar soils: 5 percent 198 Soil Survey

Management Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days For management information about this map unit, Surface layer texture: Gravelly loam see appropriate sections in Part II of this publication. Drainage class: Well drained Parent material: Loamy alluvium Native plant cover type: Rangeland 161B—Martinsdale gravelly loam, Available water capacity: Mainly 9.0 inches 0 to 4 percent slopes Additional Components Fairfield and similar soils: 4 percent Setting Farnuf and similar soils: 4 percent Elevation: 4,200 to 6,000 feet Shawmut and similar soils: 4 percent Mean annual precipitation: 15 to 19 inches Tamaneen and similar soils: 3 percent Frost-free period: 85 to 115 days Management Major Component Description For management information about this map unit, Martinsdale and similar soils see appropriate sections in Part II of this publication. Composition: 85 percent Geomorphic description: Tread on terrace Slope: 0 to 4 percent 163C—Absher clay, 0 to 8 percent slopes Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Setting Frost-free period: 85 to 115 days Landscape: Sedimentary plains Surface layer texture: Gravelly loam Elevation: 3,750 to 5,200 feet Drainage class: Well drained Mean annual precipitation: 10 to 14 inches Parent material: Loamy alluvium Frost-free period: 95 to 125 days Native plant cover type: Rangeland Available water capacity: Mainly 7.7 inches Major Component Description Additional Components Absher and similar soils Composition: 85 percent Fairfield and similar soils: 4 percent Geomorphic description: Tread on stream terrace Farnuf and similar soils: 4 percent Slope: 0 to 8 percent Shawmut and similar soils: 4 percent Elevation: 3,750 to 5,200 feet Tamaneen and similar soils: 3 percent Effective annual precipitation: 10 to 14 inches Management Frost-free period: 95 to 125 days Surface layer texture: Clay For management information about this map unit, Drainage class: Well drained see appropriate sections in Part II of this publication. Parent material: Silty and clayey alluvium weathered from igneous and sedimentary rock 161C—Martinsdale gravelly loam, 4 to 8 Native plant cover type: Rangeland percent slopes Salt affected: Saline within 30 inches Sodium affected: Sodic within 30 inches Available water capacity: Mainly 3.9 inches Setting Additional Components Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Creed and similar soils: 4 percent Frost-free period: 85 to 115 days Gerdrum and similar soils: 4 percent Lallie and similar soils: 3 percent Major Component Description Ledger and similar soils: 2 percent Martinsdale and similar soils Thibadeau and similar soils: 2 percent Composition: 85 percent Management Geomorphic description: Fan Slope: 4 to 8 percent For management information about this map unit, Elevation: 4,200 to 6,000 feet see appropriate sections in Part II of this publication. Sweet Grass County Area, Montana—Part I 199

166B—Richey silty clay, 0 to 4 percent Native plant cover type: Rangeland slopes Available water capacity: Mainly 8.7 inches Additional Components Setting Tanna and similar soils: 5 percent Elevation: 3,750 to 5,200 feet Note: This soil exists on the upper one third of the Mean annual precipitation: 10 to 14 inches landform. Frost-free period: 95 to 125 days Kremlin and similar soils: 4 percent Ethridge and similar soils: 3 percent Major Component Description Management Richey and similar soils Composition: 86 percent For management information about this map unit, Geomorphic description: Tread on stream terrace see appropriate sections in Part II of this publication. Slope: 0 to 4 percent Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches 167F—Yawdim-Birney-Rock outcrop Frost-free period: 95 to 125 days complex, 15 to 60 percent slopes Surface layer texture: Silty clay Drainage class: Well drained Setting Parent material: Clayey alluvium Elevation: 3,750 to 5,200 feet Native plant cover type: Rangeland Mean annual precipitation: 10 to 14 inches Available water capacity: Mainly 8.7 inches Frost-free period: 95 to 125 days Additional Components Major Component Description Ethridge and similar soils: 9 percent Yawdim and similar soils Kremlin and similar soils: 5 percent Composition: 40 percent Management Geomorphic description: • Nose slope summit on escarpment For management information about this map unit, • Nose slope shoulder on escarpment see appropriate sections in Part II of this publication. • Side slope shoulder on escarpment Slope: 15 to 60 percent 166C—Richey silty clay, 4 to 8 percent Elevation: 3,750 to 5,200 feet slopes Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Surface layer texture: Clay Setting Depth to bedrock (paralithic): 10 to 20 inches Elevation: 3,750 to 5,200 feet Drainage class: Well drained Mean annual precipitation: 10 to 14 inches Parent material: Clayey residuum weathered from Frost-free period: 95 to 125 days calcareous shale Native plant cover type: Rangeland Major Component Description Available water capacity: Mainly 2.0 inches Richey and similar soils Composition: 88 percent Birney and similar soils Geomorphic description: Fan Composition: 30 percent Slope: 4 to 8 percent Geomorphic description: Elevation: 3,750 to 5,200 feet • Base slope toeslope on escarpment Effective annual precipitation: 10 to 14 inches • Base slope footslope on escarpment Frost-free period: 95 to 125 days Slope: 15 to 60 percent Surface layer texture: Silty clay Elevation: 3,750 to 5,200 feet Drainage class: Well drained Effective annual precipitation: 10 to 14 inches Parent material: Clayey alluvium Frost-free period: 95 to 125 days 200 Soil Survey

Surface layer texture: Loam Management Drainage class: Well drained For management information about this map unit, Parent material: Gravelly colluvium see appropriate sections in Part II of this publication. Native plant cover type: Forestland Available water capacity: Mainly 4.7 inches

Rock outcrop 169C—Ethridge-Tanna clay loams, Composition: 20 percent 2 to 8 percent slopes Definition: Rock outcrop consists mainly of areas of exposed hard bedrock. Setting Geomorphic description: Escarpment Elevation: 3,750 to 5,200 feet Additional Components Mean annual precipitation: 10 to 14 inches Cabbart and similar soils: 4 percent Frost-free period: 95 to 125 days Rentsac and similar soils: 3 percent Yamacall and similar soils: 3 percent Major Component Description Management Ethridge and similar soils Composition: 53 percent For management information about this map unit, Geomorphic description: Plain and swale see appropriate sections in Part II of this publication. Slope: 4 to 8 percent Elevation: 3,750 to 5,200 feet 168D—Chinook fine sandy loam, Effective annual precipitation: 10 to 14 inches 8 to 15 percent slopes Frost-free period: 95 to 125 days Surface layer texture: Clay loam Drainage class: Well drained Setting Parent material: Clayey alluvium Elevation: 3,750 to 5,200 feet Native plant cover type: Rangeland Mean annual precipitation: 10 to 14 inches Available water capacity: Mainly 9.7 inches Frost-free period: 95 to 125 days Tanna and similar soils Major Component Description Composition: 43 percent Chinook and similar soils Geomorphic description: Plain and swale Composition: 85 percent Slope: 2 to 8 percent Geomorphic description: Plain and swale Elevation: 3,750 to 5,200 feet Slope: 8 to 15 percent Effective annual precipitation: 10 to 14 inches Elevation: 3,750 to 5,200 feet Frost-free period: 95 to 125 days Effective annual precipitation: 10 to 14 inches Surface layer texture: Clay loam Frost-free period: 95 to 125 days Depth to bedrock (paralithic): 20 to 40 inches Surface layer texture: Fine sandy loam Drainage class: Well drained Drainage class: Well drained Parent material: Clayey residuum weathered from Parent material: Sandy residuum weathered from sandstone and shale sandstone Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 4.2 inches Available water capacity: Mainly 8.2 inches Additional Components Additional Components Cabbart and similar soils: 4 percent Twilight and similar soils: 5 percent Management Blacksheep and similar soils: 4 percent Cabbart and similar soils: 3 percent For management information about this map unit, Delpoint and similar soils: 3 percent see appropriate sections in Part II of this publication. Sweet Grass County Area, Montana—Part I 201

170C—Gerdrum-Creed complex, 172C—Tanna-Boxwell, calcareous, 0 to 8 percent slopes complex, 2 to 8 percent slopes

Setting Setting Elevation: 3,750 to 5,200 feet Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Mean annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Frost-free period: 95 to 125 days Major Component Description Major Component Description Tanna and similar soils Gerdrum and similar soils Composition: 50 percent Composition: 50 percent Geomorphic description: Plain and swale Geomorphic description: Microlow on plain Slope: 2 to 8 percent Slope: 0 to 8 percent Elevation: 3,750 to 5,200 feet Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Frost-free period: 95 to 125 days Surface layer texture: Clay loam Surface layer texture: Clay loam Depth to bedrock (paralithic): 20 to 40 inches Drainage class: Well drained Drainage class: Well drained Parent material: Clayey alluvium Parent material: Clayey residuum weathered from Native plant cover type: Rangeland sandstone and shale Salt affected: Saline within 30 inches Native plant cover type: Rangeland Sodium affected: Sodic within 30 inches Available water capacity: Mainly 4.2 inches Available water capacity: Mainly 6.0 inches Boxwell and similar soils Creed and similar soils Composition: 40 percent Composition: 40 percent Geomorphic description: Plain and swale Geomorphic description: Microhigh on plain Slope: 2 to 8 percent Slope: 0 to 8 percent Elevation: 3,750 to 5,200 feet Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Frost-free period: 95 to 125 days Surface layer texture: Loam Surface layer texture: Loam Depth to bedrock (paralithic): 20 to 40 inches Drainage class: Well drained Drainage class: Well drained Parent material: Clayey alluvium Parent material: Loamy residuum weathered from Native plant cover type: Rangeland sandstone and siltstone Sodium affected: Sodic within 30 inches Native plant cover type: Rangeland Available water capacity: Mainly 6.4 inches Available water capacity: Mainly 5.0 inches Additional Components Additional Components Ethridge and similar soils: 4 percent Cabbart and similar soils: 5 percent Tanna and similar soils: 3 percent Ethridge and similar soils: 2 percent Absher and similar soils: 2 percent Marmarth and similar soils: 2 percent Yawdim and similar soils: 1 percent Kremlin and similar soils: 1 percent Management Management For management information about this map unit, For management information about this map unit, see appropriate sections in Part II of this publication. see appropriate sections in Part II of this publication. 202 Soil Survey

172D—Tanna-Boxwell, calcareous, 174C—Sweetgrass clay loam, complex, 8 to 15 percent slopes 2 to 8 percent slopes

Setting Setting Elevation: 3,750 to 5,200 feet Elevation: 4,200 to 6,000 feet Mean annual precipitation: 10 to 14 inches Mean annual precipitation: 15 to 19 inches Frost-free period: 95 to 125 days Frost-free period: 85 to 115 days Major Component Description Major Component Description Tanna and similar soils Sweetgrass and similar soils Composition: 50 percent Composition: 85 percent Geomorphic description: Plain and swale Geomorphic description: Fan Slope: 8 to 15 percent Slope: 2 to 8 percent Elevation: 3,750 to 5,200 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 10 to 14 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 95 to 125 days Frost-free period: 85 to 115 days Surface layer texture: Clay loam Surface layer texture: Clay loam Depth to bedrock (paralithic): 20 to 40 inches Drainage class: Well drained Drainage class: Well drained Parent material: Clayey over sandy and gravelly Parent material: Clayey residuum weathered from alluvium sandstone and shale Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 5.6 inches Available water capacity: Mainly 4.2 inches Additional Components Boxwell and similar soils Danvers and similar soils: 3 percent Composition: 40 percent Roy and similar soils: 3 percent Geomorphic description: Plain and swale Shawmut and similar soils: 3 percent Slope: 8 to 15 percent Tamaneen and similar soils: 3 percent Elevation: 3,750 to 5,200 feet Work and similar soils: 3 percent Effective annual precipitation: 10 to 14 inches Management Frost-free period: 95 to 125 days Surface layer texture: Loam For management information about this map unit, Depth to bedrock (paralithic): 20 to 40 inches see appropriate sections in Part II of this publication. Drainage class: Well drained Parent material: Loamy residuum weathered from sandstone and siltstone 176C—Reedwest-Cabba loams, Native plant cover type: Rangeland 2 to 8 percent slopes Available water capacity: Mainly 5.0 inches Additional Components Setting Cabbart and similar soils: 5 percent Elevation: 4,200 to 6,000 feet Ethridge and similar soils: 2 percent Mean annual precipitation: 15 to 19 inches Marmarth and similar soils: 2 percent Frost-free period: 85 to 115 days Kremlin and similar soils: 1 percent Major Component Description Management Reedwest and similar soils For management information about this map unit, Composition: 50 percent see appropriate sections in Part II of this publication. Geomorphic description: Plain and swale Sweet Grass County Area, Montana—Part I 203

Slope: 2 to 8 percent Slope: 15 to 60 percent Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Surface layer texture: Loam Surface layer texture: Channery loam Depth to bedrock (paralithic): 20 to 40 inches Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained Parent material: Loamy residuum weathered from Parent material: Residuum weathered from sandstone and siltstone sandstone Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 4.6 inches Available water capacity: Mainly 1.4 inches Note: This soil exists on the lower one third of the Cabba and similar soils landform. Composition: 40 percent Geomorphic description: Knoll and plain Roy and similar soils Slope: 2 to 8 percent Composition: 40 percent Elevation: 4,200 to 6,000 feet Geomorphic description: Side slope backslope on Effective annual precipitation: 15 to 19 inches escarpment Frost-free period: 85 to 115 days Slope: 15 to 60 percent Surface layer texture: Loam Elevation: 4,200 to 6,000 feet Depth to bedrock (paralithic): 10 to 20 inches Effective annual precipitation: 15 to 19 inches Drainage class: Well drained Frost-free period: 85 to 115 days Parent material: Loamy residuum weathered from Surface layer texture: Gravelly clay loam sandstone and siltstone Drainage class: Well drained Native plant cover type: Rangeland Parent material: Gravelly alluvium Available water capacity: Mainly 2.5 inches Native plant cover type: Rangeland Available water capacity: Mainly 4.5 inches Additional Components Note: This soil exists on the upper one third of the Amherst and similar soils: 3 percent landform. Farnuf and similar soils: 3 percent Absarokee and similar soils: 2 percent Additional Components Castner and similar soils: 2 percent Wayden and similar soils: 5 percent Management Note: This soil exists on the lower two thirds of the landform. For management information about this map unit, Absarokee and similar soils: 3 percent see appropriate sections in Part II of this publication. Amherst and similar soils: 2 percent Management 178F—Castner-Roy complex, 15 to 60 percent slopes For management information about this map unit, see appropriate sections in Part II of this publication. Setting Elevation: 4,200 to 6,000 feet 179F—Cabba-Rock outcrop complex, Mean annual precipitation: 15 to 19 inches 15 to 60 percent slopes Frost-free period: 85 to 115 days Major Component Description Setting Castner and similar soils Field investigation intensity: Order 2 Composition: 50 percent Elevation: 4,200 to 6,000 feet Geomorphic description: Side slope backslope on Mean annual precipitation: 15 to 19 inches escarpment Frost-free period: 85 to 115 days 204 Soil Survey

Major Component Description Depth to bedrock (paralithic): 10 to 20 inches Drainage class: Well drained Cabba and similar soils Parent material: Loamy residuum weathered from Composition: 70 percent sandstone and siltstone Geomorphic description: Native plant cover type: Rangeland • Nose slope summit on escarpment Available water capacity: Mainly 2.4 inches • Nose slope backslope on escarpment • Side slope backslope on escarpment Winifred and similar soils Slope: 15 to 60 percent Composition: 40 percent Elevation: 4,200 to 6,000 feet Geomorphic description: Plain and swale Effective annual precipitation: 15 to 19 inches Slope: 2 to 8 percent Frost-free period: 85 to 115 days Elevation: 4,200 to 6,000 feet Surface layer texture: Loam Effective annual precipitation: 15 to 19 inches Depth to bedrock (paralithic): 10 to 20 inches Frost-free period: 85 to 115 days Drainage class: Well drained Surface layer texture: Clay loam Parent material: Loamy residuum weathered from Depth to bedrock (paralithic): 20 to 40 inches sandstone and siltstone Drainage class: Well drained Native plant cover type: Rangeland Parent material: Clayey residuum weathered from Available water capacity: Mainly 2.0 inches sandstone and shale Native plant cover type: Rangeland Rock outcrop Available water capacity: Mainly 5.3 inches Composition: 20 percent Definition: Rock outcrop consists mainly of areas of Additional Components exposed hard bedrock. Castner and similar soils: 3 percent Geomorphic description: Escarpment Wayden and similar soils: 3 percent Additional Components Linwell and similar soils: 2 percent Work and similar soils: 2 percent Doney and similar soils: 3 percent Macar and similar soils: 3 percent Management Castner and similar soils: 2 percent For management information about this map unit, Wayden and similar soils: 2 percent see appropriate sections in Part II of this publication. Management For management information about this map unit, 181D—Cabba-Winifred clay loams, see appropriate sections in Part II of this publication. 8 to 15 percent slopes

Setting 181C—Cabba-Winifred clay loams, 2 to 8 percent slopes Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Setting Major Component Description Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Cabba and similar soils Frost-free period: 85 to 115 days Composition: 50 percent Geomorphic description: Major Component Description • Nose slope summit on hill Cabba and similar soils • Nose slope backslope on hill Composition: 50 percent • Side slope backslope on hill Geomorphic description: Knoll and plain Slope: 8 to 15 percent Slope: 2 to 8 percent Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Surface layer texture: Clay loam Surface layer texture: Clay loam Depth to bedrock (paralithic): 10 to 20 inches Sweet Grass County Area, Montana—Part I 205

Drainage class: Well drained Frost-free period: 85 to 115 days Parent material: Loamy residuum weathered from Surface layer texture: Gravelly clay loam sandstone and siltstone Drainage class: Well drained Native plant cover type: Rangeland Parent material: Gravelly glaciofluvial deposits Available water capacity: Mainly 2.4 inches Native plant cover type: Rangeland Available water capacity: Mainly 4.5 inches Winifred and similar soils Additional Components Composition: 40 percent Geomorphic description: Tamaneen and similar soils: 5 percent • Base slope backslope on hill Bacbuster and similar soils: 3 percent • Base slope footslope on hill Danvers and similar soils: 3 percent • Side slope backslope on hill Shawmut and similar soils: 3 percent Slope: 8 to 15 percent Turner and similar soils: 1 percent Elevation: 4,200 to 6,000 feet Management Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days For management information about this map unit, Surface layer texture: Clay loam see appropriate sections in Part II of this publication. Depth to bedrock (paralithic): 20 to 40 inches Drainage class: Well drained Parent material: Clayey residuum weathered from 182D—Roy gravelly clay loam, sandstone and shale 8 to 15 percent slopes Native plant cover type: Rangeland Available water capacity: Mainly 5.3 inches Setting Additional Components Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Wayden and similar soils: 3 percent Frost-free period: 85 to 115 days Amherst and similar soils: 2 percent Castner and similar soils: 2 percent Major Component Description Work and similar soils: 2 percent Roy and similar soils Rock outcrop: 1 percent Composition: 85 percent Management Geomorphic description: Fan Slope: 8 to 15 percent For management information about this map unit, Elevation: 4,200 to 6,000 feet see appropriate sections in Part II of this publication. Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days 182C—Roy gravelly clay loam, Surface layer texture: Gravelly clay loam 2 to 8 percent slopes Drainage class: Well drained Parent material: Gravelly glaciofluvial deposits Native plant cover type: Rangeland Setting Available water capacity: Mainly 4.5 inches Elevation: 4,200 to 6,000 feet Additional Components Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Shawmut and similar soils: 5 percent Roy and similar soils: 3 percent Major Component Description Tamaneen and similar soils: 3 percent Roy and similar soils Danvers and similar soils: 2 percent Composition: 85 percent Turner and similar soils: 2 percent Geomorphic description: Tread on terrace Management Slope: 2 to 8 percent Elevation: 4,200 to 6,000 feet For management information about this map unit, Effective annual precipitation: 15 to 19 inches see appropriate sections in Part II of this publication. 206 Soil Survey

183A—Tamaneen gravelly loam, Native plant cover type: Rangeland 0 to 2 percent slopes Available water capacity: Mainly 6.7 inches Additional Components Setting Roy and similar soils: 9 percent Elevation: 4,200 to 6,000 feet Danvers and similar soils: 5 percent Mean annual precipitation: 15 to 19 inches Sagedale and similar soils: 1 percent Frost-free period: 85 to 115 days Management Major Component Description For management information about this map unit, Tamaneen and similar soils see appropriate sections in Part II of this publication. Composition: 85 percent Geomorphic description: Tread on terrace Slope: 0 to 2 percent 183C—Tamaneen gravelly clay loam, Elevation: 4,200 to 6,000 feet 2 to 8 percent slopes Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Setting Surface layer texture: Gravelly loam Elevation: 4,200 to 6,000 feet Drainage class: Well drained Mean annual precipitation: 15 to 19 inches Parent material: Clayey over gravelly alluvium Frost-free period: 85 to 115 days Native plant cover type: Rangeland Available water capacity: Mainly 6.5 inches Major Component Description Additional Components Tamaneen and similar soils Composition: 85 percent Fairfield and similar soils: 5 percent Geomorphic description: Tread on terrace Roy and similar soils: 5 percent Slope: 2 to 8 percent Danvers and similar soils: 3 percent Elevation: 4,200 to 6,000 feet Shawmut and similar soils: 2 percent Effective annual precipitation: 15 to 19 inches Management Frost-free period: 85 to 115 days Surface layer texture: Gravelly clay loam For management information about this map unit, Drainage class: Well drained see appropriate sections in Part II of this publication. Parent material: Clayey over gravelly alluvium Native plant cover type: Rangeland Available water capacity: Mainly 6.5 inches 183B—Tamaneen clay loam, 0 to 4 percent slopes Additional Components Danvers and similar soils: 6 percent Setting Martinsdale and similar soils: 3 percent Roy and similar soils: 3 percent Elevation: 4,200 to 6,000 feet Shawmut and similar soils: 3 percent Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Management Major Component Description For management information about this map unit, see appropriate sections in Part II of this publication. Tamaneen and similar soils Composition: 85 percent Geomorphic description: Tread on terrace 184D—Absarokee-Shambo loams, Slope: 0 to 4 percent 8 to 15 percent slopes Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Setting Frost-free period: 85 to 115 days Surface layer texture: Clay loam Elevation: 4,200 to 6,000 feet Drainage class: Well drained Mean annual precipitation: 15 to 19 inches Parent material: Clayey over gravelly alluvium Frost-free period: 85 to 115 days Sweet Grass County Area, Montana—Part I 207

Major Component Description Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Absarokee and similar soils Surface layer texture: Loam Composition: 50 percent Depth to bedrock (paralithic): 20 to 40 inches Geomorphic description: Plain and swale Drainage class: Well drained Slope: 8 to 15 percent Parent material: Loamy residuum weathered from Elevation: 4,200 to 6,000 feet sandstone and siltstone Effective annual precipitation: 15 to 19 inches Native plant cover type: Rangeland Frost-free period: 85 to 115 days Available water capacity: Mainly 6.1 inches Surface layer texture: Loam Depth to bedrock (lithic): 20 to 40 inches Castner and similar soils Drainage class: Well drained Composition: 40 percent Parent material: Silty and clayey residuum weathered Geomorphic description: Knoll and plain from sandstone and shale Slope: 2 to 8 percent Native plant cover type: Rangeland Elevation: 4,200 to 6,000 feet Available water capacity: Mainly 4.1 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Shambo and similar soils Surface layer texture: Channery loam Composition: 40 percent Depth to bedrock (lithic): 10 to 20 inches Geomorphic description: Plain and swale Drainage class: Well drained Slope: 8 to 15 percent Parent material: Residuum weathered from Elevation: 4,200 to 6,000 feet sandstone Effective annual precipitation: 15 to 19 inches Native plant cover type: Rangeland Frost-free period: 85 to 115 days Available water capacity: Mainly 1.6 inches Surface layer texture: Loam Drainage class: Well drained Additional Components Parent material: Loamy alluvium Ticell and similar soils: 4 percent Native plant cover type: Rangeland Wayden and similar soils: 4 percent Available water capacity: Mainly 10.7 inches Reedwest and similar soils: 2 percent Additional Components Management Work and similar soils: 5 percent For management information about this map unit, Reedwest and similar soils: 3 percent see appropriate sections in Part II of this publication. Castner and similar soils: 2 percent Management 185D—Amor-Castner complex, For management information about this map unit, 8 to 15 percent slopes see appropriate sections in Part II of this publication. Setting 185C—Amor-Castner complex, Elevation: 4,200 to 6,000 feet 2 to 8 percent slopes Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Setting Major Component Description Elevation: 4,200 to 6,000 feet Amor and similar soils Mean annual precipitation: 15 to 19 inches Composition: 50 percent Frost-free period: 85 to 115 days Geomorphic description: Plain and swale Slope: 8 to 15 percent Major Component Description Elevation: 4,200 to 6,000 feet Amor and similar soils Effective annual precipitation: 15 to 19 inches Composition: 50 percent Frost-free period: 85 to 115 days Geomorphic description: Plain and swale Surface layer texture: Loam Slope: 2 to 8 percent Depth to bedrock (paralithic): 20 to 40 inches Elevation: 4,200 to 6,000 feet Drainage class: Well drained 208 Soil Survey

Parent material: Loamy residuum weathered from Native plant cover type: Rangeland sandstone and siltstone Available water capacity: Mainly 1.6 inches Native plant cover type: Rangeland Additional Components Available water capacity: Mainly 6.1 inches Rock outcrop: 5 percent Castner and similar soils Absarokee and similar soils: 3 percent Composition: 40 percent Cabba and similar soils: 3 percent Geomorphic description: Knoll and plain Amherst and similar soils: 2 percent Slope: 8 to 15 percent Farnuf and similar soils: 2 percent Elevation: 4,200 to 6,000 feet Management Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days For management information about this map unit, Surface layer texture: Channery loam see appropriate sections in Part II of this publication. Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Parent material: Residuum weathered from 186E—Castner channery loam, sandstone 15 to 35 percent slopes Native plant cover type: Rangeland Available water capacity: Mainly 1.6 inches Setting Additional Components Elevation: 4,200 to 6,000 feet Cabba and similar soils: 4 percent Mean annual precipitation: 15 to 19 inches Wayden and similar soils: 3 percent Frost-free period: 85 to 115 days Reedwest and similar soils: 2 percent Rock outcrop: 1 percent Major Component Description Management Castner and similar soils Composition: 85 percent For management information about this map unit, Geomorphic description: see appropriate sections in Part II of this publication. • Nose slope summit on hill • Nose slope shoulder on hill 186D—Castner channery loam, Slope: 15 to 35 percent 2 to 15 percent slopes Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Setting Surface layer texture: Channery loam Elevation: 4,200 to 6,000 feet Depth to bedrock (lithic): 10 to 20 inches Mean annual precipitation: 15 to 19 inches Drainage class: Well drained Frost-free period: 85 to 115 days Parent material: Residuum weathered from sandstone Major Component Description Native plant cover type: Rangeland Castner and similar soils Available water capacity: Mainly 1.4 inches Composition: 85 percent Additional Components Geomorphic description: Knoll and plain Slope: 2 to 15 percent Rock outcrop: 4 percent Elevation: 4,200 to 6,000 feet Absarokee and similar soils: 3 percent Effective annual precipitation: 15 to 19 inches Shawmut and similar soils: 3 percent Frost-free period: 85 to 115 days Wayden and similar soils: 3 percent Surface layer texture: Channery loam Cabba and similar soils: 2 percent Depth to bedrock (lithic): 10 to 20 inches Management Drainage class: Well drained Parent material: Residuum weathered from For management information about this map unit, sandstone see appropriate sections in Part II of this publication. Sweet Grass County Area, Montana—Part I 209

188C—Linwell clay loam, 2 to 8 percent Native plant cover type: Rangeland slopes Available water capacity: Mainly 10.4 inches Additional Components Setting Farnuf and similar soils: 8 percent Elevation: 4,200 to 6,000 feet Linwell and similar soils: 4 percent Mean annual precipitation: 15 to 19 inches Work and similar soils: 3 percent Frost-free period: 85 to 115 days Management Major Component Description For management information about this map unit, Linwell and similar soils see appropriate sections in Part II of this publication. Composition: 85 percent Geomorphic description: Fan Slope: 2 to 8 percent 190C—Danvers gravelly clay loam, Elevation: 4,200 to 6,000 feet 2 to 8 percent slopes Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Setting Surface layer texture: Clay loam Drainage class: Well drained Elevation: 4,200 to 6,000 feet Parent material: Clayey alluvium Mean annual precipitation: 15 to 19 inches Native plant cover type: Rangeland Frost-free period: 85 to 115 days Available water capacity: Mainly 9.1 inches Major Component Description Additional Components Danvers and similar soils Overfelt and similar soils: 4 percent Composition: 85 percent Shambo and similar soils: 4 percent Geomorphic description: Fan Work and similar soils: 4 percent Slope: 2 to 8 percent Roy and similar soils: 3 percent Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Management Frost-free period: 85 to 115 days For management information about this map unit, Surface layer texture: Gravelly clay loam see appropriate sections in Part II of this publication. Drainage class: Well drained Parent material: Loamy alluvium Native plant cover type: Rangeland 189C—Shambo gravelly clay loam, Available water capacity: Mainly 6.4 inches 2 to 8 percent slopes Additional Components Setting Tamaneen and similar soils: 7 percent Sagedale and similar soils: 4 percent Elevation: 4,200 to 6,000 feet Shawmut and similar soils: 4 percent Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Management Major Component Description For management information about this map unit, see appropriate sections in Part II of this publication. Shambo and similar soils Composition: 85 percent Geomorphic description: Fan 191C—Castner-Farnuf complex, Slope: 2 to 8 percent 2 to 8 percent slopes Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Setting Frost-free period: 85 to 115 days Surface layer texture: Gravelly clay loam Elevation: 4,200 to 6,000 feet Drainage class: Well drained Mean annual precipitation: 15 to 19 inches Parent material: Loamy alluvium Frost-free period: 85 to 115 days 210 Soil Survey

Major Component Description Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Castner and similar soils Surface layer texture: Channery loam Composition: 50 percent Depth to bedrock (lithic): 10 to 20 inches Geomorphic description: Knoll and plain Drainage class: Well drained Slope: 2 to 8 percent Parent material: Residuum weathered from Elevation: 4,200 to 6,000 feet sandstone Effective annual precipitation: 15 to 19 inches Native plant cover type: Rangeland Frost-free period: 85 to 115 days Available water capacity: Mainly 1.6 inches Surface layer texture: Channery loam Depth to bedrock (lithic): 10 to 20 inches Shambo and similar soils Drainage class: Well drained Composition: 40 percent Parent material: Residuum weathered from Geomorphic description: Plain and swale sandstone Slope: 8 to 15 percent Native plant cover type: Rangeland Elevation: 4,200 to 6,000 feet Available water capacity: Mainly 1.6 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Farnuf and similar soils Surface layer texture: Loam Composition: 40 percent Drainage class: Well drained Geomorphic description: Plain and swale Parent material: Loamy alluvium Slope: 2 to 8 percent Native plant cover type: Rangeland Elevation: 4,200 to 6,000 feet Available water capacity: Mainly 10.7 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Additional Components Surface layer texture: Loam Amherst and similar soils: 3 percent Drainage class: Well drained Reedwest and similar soils: 3 percent Parent material: Loamy alluvium Cabba and similar soils: 2 percent Native plant cover type: Rangeland Wayden and similar soils: 2 percent Available water capacity: Mainly 9.6 inches Management Additional Components For management information about this map unit, Cabba and similar soils: 4 percent see appropriate sections in Part II of this publication. Absarokee and similar soils: 3 percent Wayden and similar soils: 3 percent Management 193C—Farnuf-Winifred complex, For management information about this map unit, 2 to 8 percent slopes see appropriate sections in Part II of this publication. Setting 192D—Castner-Shambo complex, Elevation: 4,200 to 6,000 feet 8 to 15 percent slopes Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Setting Major Component Description Elevation: 4,200 to 6,000 feet Farnuf and similar soils Mean annual precipitation: 15 to 19 inches Composition: 50 percent Frost-free period: 85 to 115 days Geomorphic description: Plain and swale Slope: 2 to 8 percent Major Component Description Elevation: 4,200 to 6,000 feet Castner and similar soils Effective annual precipitation: 15 to 19 inches Composition: 50 percent Frost-free period: 85 to 115 days Geomorphic description: Knoll and plain Surface layer texture: Loam Slope: 8 to 15 percent Drainage class: Well drained Elevation: 4,200 to 6,000 feet Parent material: Loamy alluvium Sweet Grass County Area, Montana—Part I 211

Native plant cover type: Rangeland Elevation: 4,200 to 6,000 feet Available water capacity: Mainly 9.6 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Winifred and similar soils Surface layer texture: Loam Composition: 40 percent Depth to bedrock (paralithic): 20 to 40 inches Geomorphic description: Plain and swale Drainage class: Well drained Slope: 2 to 8 percent Parent material: Loamy residuum weathered from Elevation: 4,200 to 6,000 feet sandstone and siltstone Effective annual precipitation: 15 to 19 inches Native plant cover type: Rangeland Frost-free period: 85 to 115 days Available water capacity: Mainly 6.1 inches Surface layer texture: Clay loam Additional Components Depth to bedrock (paralithic): 20 to 40 inches Drainage class: Well drained Doney and similar soils: 4 percent Parent material: Clayey residuum weathered from Ticell and similar soils: 4 percent sandstone and shale Macar and similar soils: 2 percent Native plant cover type: Rangeland Management Available water capacity: Mainly 5.3 inches For management information about this map unit, Additional Components see appropriate sections in Part II of this publication. Wayden and similar soils: 4 percent Reedwest and similar soils: 3 percent Work and similar soils: 3 percent 196B—Yamacall-Bigsag family complex, 0 to 4 percent slopes Management For management information about this map unit, Setting see appropriate sections in Part II of this publication. Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches 194C—Linwell-Amor complex, Frost-free period: 95 to 125 days 2 to 8 percent slopes Major Component Description Yamacall and similar soils Setting Composition: 50 percent Elevation: 4,200 to 6,000 feet Geomorphic description: Stream terrace Mean annual precipitation: 15 to 19 inches Slope: 1 to 4 percent Frost-free period: 85 to 115 days Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Major Component Description Frost-free period: 95 to 125 days Linwell and similar soils Surface layer texture: Loam Composition: 50 percent Drainage class: Well drained Geomorphic description: Plain and swale Parent material: Loamy alluvium Slope: 2 to 8 percent Native plant cover type: Rangeland Elevation: 4,200 to 6,000 feet Available water capacity: Mainly 9.6 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Bigsag and similar soils Surface layer texture: Clay loam Composition: 40 percent Drainage class: Well drained Geomorphic description: Depression and flood plain Parent material: Clayey alluvium Slope: 0 to 4 percent Native plant cover type: Rangeland Elevation: 3,750 to 5,200 feet Available water capacity: Mainly 9.1 inches Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Amor and similar soils Surface layer texture: Clay Composition: 40 percent Drainage class: Very poorly drained Geomorphic description: Plain and swale Parent material: Clayey colluvium weathered from Slope: 2 to 8 percent sandstone and shale 212 Soil Survey

Native plant cover type: Rangeland Additional Components Water table: Present Absarokee and similar soils: 5 percent Ponding duration: Long Cabba and similar soils: 3 percent Salt affected: Saline within 30 inches Amherst and similar soils: 2 percent Available water capacity: Mainly 7.8 inches Management Additional Components For management information about this map unit, Lallie and similar soils: 5 percent see appropriate sections in Part II of this publication. Kobase and similar soils: 3 percent Klayent and similar soils: 2 percent Management 197D—Work-Castner complex, 8 to 15 percent slopes For management information about this map unit, see appropriate sections in Part II of this publication. Setting Elevation: 4,200 to 6,000 feet 197C—Work-Castner complex, Mean annual precipitation: 15 to 19 inches 2 to 8 percent slopes Frost-free period: 85 to 115 days Major Component Description Setting Work and similar soils Elevation: 4,200 to 6,000 feet Composition: 60 percent Mean annual precipitation: 15 to 19 inches Geomorphic description: Plain and swale Frost-free period: 85 to 115 days Slope: 8 to 15 percent Elevation: 4,200 to 6,000 feet Major Component Description Effective annual precipitation: 15 to 19 inches Work and similar soils Frost-free period: 85 to 115 days Composition: 60 percent Surface layer texture: Clay loam Geomorphic description: Plain and swale Drainage class: Well drained Slope: 2 to 8 percent Parent material: Clayey alluvium Elevation: 4,200 to 6,000 feet Native plant cover type: Rangeland Effective annual precipitation: 15 to 19 inches Available water capacity: Mainly 8.6 inches Frost-free period: 85 to 115 days Surface layer texture: Clay loam Castner and similar soils Drainage class: Well drained Composition: 30 percent Parent material: Clayey alluvium Geomorphic description: Knoll and plain Native plant cover type: Rangeland Slope: 8 to 15 percent Available water capacity: Mainly 8.6 inches Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Castner and similar soils Frost-free period: 85 to 115 days Composition: 30 percent Surface layer texture: Channery loam Geomorphic description: Knoll and plain Depth to bedrock (lithic): 10 to 20 inches Slope: 2 to 8 percent Drainage class: Well drained Elevation: 4,200 to 6,000 feet Parent material: Residuum weathered from Effective annual precipitation: 15 to 19 inches sandstone Frost-free period: 85 to 115 days Native plant cover type: Rangeland Surface layer texture: Channery loam Available water capacity: Mainly 1.6 inches Depth to bedrock (lithic): 10 to 20 inches Additional Components Drainage class: Well drained Parent material: Residuum weathered from Absarokee and similar soils: 4 percent sandstone Cabba and similar soils: 2 percent Native plant cover type: Rangeland Farnuf and similar soils: 2 percent Available water capacity: Mainly 1.6 inches Macar and similar soils: 2 percent Sweet Grass County Area, Montana—Part I 213

Management 202C—Castner-Absarokee complex, For management information about this map unit, 2 to 8 percent slopes see appropriate sections in Part II of this publication. Setting 201F—Yawdim-Rock outcrop complex, Elevation: 4,200 to 6,000 feet 15 to 60 percent slopes Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Setting Major Component Description Elevation: 3,750 to 5,200 feet Castner and similar soils Mean annual precipitation: 10 to 14 inches Composition: 50 percent Frost-free period: 95 to 125 days Geomorphic description: Knoll and plain Slope: 2 to 8 percent Major Component Description Elevation: 4,200 to 6,000 feet Yawdim and similar soils Effective annual precipitation: 15 to 19 inches Composition: 70 percent Frost-free period: 85 to 115 days Geomorphic description: Surface layer texture: Channery loam • Nose slope summit on escarpment Depth to bedrock (lithic): 10 to 20 inches • Nose slope shoulder on escarpment Drainage class: Well drained • Side slope shoulder on escarpment Parent material: Residuum weathered from Slope: 15 to 60 percent sandstone Elevation: 3,750 to 5,200 feet Native plant cover type: Rangeland Effective annual precipitation: 10 to 14 inches Available water capacity: Mainly 1.6 inches Frost-free period: 95 to 125 days Surface layer texture: Clay Absarokee and similar soils Depth to bedrock (paralithic): 10 to 20 inches Composition: 40 percent Drainage class: Well drained Geomorphic description: Plain and swale Parent material: Clayey residuum weathered from Slope: 2 to 8 percent calcareous shale Elevation: 4,200 to 6,000 feet Native plant cover type: Rangeland Effective annual precipitation: 15 to 19 inches Available water capacity: Mainly 2.0 inches Frost-free period: 85 to 115 days Surface layer texture: Loam Depth to bedrock (lithic): 20 to 40 inches Rock outcrop Drainage class: Well drained Composition: 20 percent Parent material: Silty and clayey residuum weathered Definition: Rock outcrop consists mainly of areas of from sandstone and shale exposed hard bedrock. Native plant cover type: Rangeland Geomorphic description: Escarpment Available water capacity: Mainly 4.1 inches Additional Components Additional Components Rentsac and similar soils: 4 percent Work and similar soils: 4 percent Cabbart and similar soils: 2 percent Amherst and similar soils: 2 percent Megonot and similar soils: 2 percent Cabba and similar soils: 2 percent Reedpoint and similar soils: 2 percent Wayden and similar soils: 2 percent Management Management For management information about this map unit, For management information about this map unit, see appropriate sections in Part II of this publication. see appropriate sections in Part II of this publication. 214 Soil Survey

202D—Castner-Absarokee complex, 202E—Castner-Absarokee complex, 8 to 15 percent slopes 15 to 35 percent slopes

Setting Setting Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Major Component Description Major Component Description Castner and similar soils Castner and similar soils Composition: 50 percent Composition: 50 percent Geomorphic description: Knoll and plain Geomorphic description: Slope: 8 to 15 percent • Nose slope summit on hill Elevation: 4,200 to 6,000 feet • Nose slope shoulder on hill Effective annual precipitation: 15 to 19 inches Slope: 15 to 35 percent Frost-free period: 85 to 115 days Elevation: 4,200 to 6,000 feet Surface layer texture: Channery loam Effective annual precipitation: 15 to 19 inches Depth to bedrock (lithic): 10 to 20 inches Frost-free period: 85 to 115 days Drainage class: Well drained Surface layer texture: Channery loam Parent material: Residuum weathered from Depth to bedrock (lithic): 10 to 20 inches sandstone Drainage class: Well drained Native plant cover type: Rangeland Parent material: Residuum weathered from Available water capacity: Mainly 1.6 inches sandstone Native plant cover type: Rangeland Absarokee and similar soils Available water capacity: Mainly 1.4 inches Composition: 40 percent Geomorphic description: Plain and swale Absarokee and similar soils Slope: 8 to 15 percent Composition: 40 percent Elevation: 4,200 to 6,000 feet Geomorphic description: Effective annual precipitation: 15 to 19 inches • Side slope backslope on hill Frost-free period: 85 to 115 days • Base slope backslope on hill Surface layer texture: Loam • Base slope footslope on hill Depth to bedrock (lithic): 20 to 40 inches Slope: 15 to 35 percent Drainage class: Well drained Elevation: 4,200 to 6,000 feet Parent material: Silty and clayey residuum weathered Effective annual precipitation: 15 to 19 inches from sandstone and shale Frost-free period: 85 to 115 days Native plant cover type: Rangeland Surface layer texture: Loam Available water capacity: Mainly 4.1 inches Depth to bedrock (lithic): 20 to 40 inches Drainage class: Well drained Additional Components Parent material: Silty and clayey residuum weathered Work and similar soils: 3 percent from sandstone and shale Amherst and similar soils: 2 percent Native plant cover type: Rangeland Cabba and similar soils: 2 percent Available water capacity: Mainly 4.1 inches Wayden and similar soils: 2 percent Additional Components Rock outcrop: 1 percent Work and similar soils: 5 percent Management Amherst and similar soils: 2 percent For management information about this map unit, Amor and similar soils: 2 percent see appropriate sections in Part II of this publication. Rock outcrop: 1 percent Sweet Grass County Area, Montana—Part I 215

Management Major Component Description For management information about this map unit, Hinterland and similar soils see appropriate sections in Part II of this publication. Composition: 40 percent Geomorphic description: Knoll and plain Slope: 2 to 15 percent 204A—Dimmick silty clay, 0 to 2 percent Elevation: 3,750 to 5,200 feet slopes Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Surface layer texture: Clay loam Setting Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Elevation: 4,200 to 5,600 feet Parent material: Residuum weathered from Mean annual precipitation: 10 to 19 inches sandstone Frost-free period: 95 to 125 days Native plant cover type: Rangeland Major Component Description Available water capacity: Mainly 2.0 inches Dimmick and similar soils Rentsac and similar soils Composition: 85 percent Composition: 30 percent Geomorphic description: Depression and plain Geomorphic description: Knoll and plain Slope: 0 to 2 percent Slope: 2 to 15 percent Elevation: 4,200 to 5,600 feet Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Frost-free period: 95 to 125 days Surface layer texture: Silty clay Surface layer texture: Channery loam Drainage class: Very poorly drained Depth to bedrock (lithic): 10 to 20 inches Parent material: Clayey alluvium Drainage class: Well drained Native plant cover type: Rangeland Parent material: Residuum weathered from Water table: Present calcareous sandstone Ponding duration: Long Native plant cover type: Rangeland Available water capacity: Mainly 10.3 inches Available water capacity: Mainly 1.4 inches Additional Components Cabbart and similar soils Gerdrum and similar soils: 6 percent Composition: 20 percent Ethridge and similar soils: 5 percent Geomorphic description: Knoll and plain Macar and similar soils: 0 to 4 percent Slope: 2 to 15 percent Yamacall and similar soils: 0 to 4 percent Elevation: 3,750 to 5,200 feet Management Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days For management information about this map unit, Surface layer texture: Loam see appropriate sections in Part II of this publication. Depth to bedrock (paralithic): 10 to 20 inches Drainage class: Well drained 206D—Hinterland-Rentsac-Cabbart Parent material: Loamy residuum weathered from complex, 2 to 15 percent slopes sandstone and siltstone Native plant cover type: Rangeland Available water capacity: Mainly 3.0 inches Setting Additional Components Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Reedpoint and similar soils: 4 percent Frost-free period: 95 to 125 days Delpoint and similar soils: 2 percent 216 Soil Survey

Marmarth and similar soils: 2 percent Additional Components Tanna and similar soils: 2 percent Doney and similar soils: 3 percent Management Bacbuster and similar soils: 2 percent Rock outcrop: 2 percent For management information about this map unit, see appropriate sections in Part II of this publication. Management For management information about this map unit, 208F—Cabba-Castner complex, see appropriate sections in Part II of this publication. 15 to 60 percent slopes

Setting 209C—Fairfield gravelly loam, 2 to 8 percent slopes Field investigation intensity: Order 2 Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Setting Frost-free period: 85 to 115 days Elevation: 4,200 to 6,000 feet Major Component Description Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Cabba and similar soils Composition: 50 percent Major Component Description Geomorphic description: Fairfield and similar soils • Nose slope backslope on escarpment Composition: 85 percent • Nose slope summit on escarpment Geomorphic description: Tread on terrace • Side slope backslope on escarpment Slope: 2 to 8 percent Slope: 15 to 60 percent Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Surface layer texture: Gravelly loam Surface layer texture: Loam Drainage class: Well drained Depth to bedrock (paralithic): 10 to 20 inches Parent material: Loamy alluvium Drainage class: Well drained Native plant cover type: Rangeland Parent material: Loamy residuum weathered from Available water capacity: Mainly 8.9 inches sandstone and siltstone Native plant cover type: Rangeland Additional Components Available water capacity: Mainly 2.0 inches Shawmut and similar soils: 7 percent Reedwest and similar soils: 4 percent Castner and similar soils Tamaneen and similar soils: 4 percent Composition: 43 percent Geomorphic description: Management • Nose slope summit on escarpment For management information about this map unit, • Nose slope shoulder on escarpment see appropriate sections in Part II of this publication. Slope: 15 to 60 percent Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days 209D—Fairfield gravelly loam, Surface layer texture: Channery loam 8 to 15 percent slopes Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Setting Parent material: Residuum weathered from sandstone Elevation: 4,200 to 6,000 feet Native plant cover type: Rangeland Mean annual precipitation: 15 to 19 inches Available water capacity: Mainly 1.4 inches Frost-free period: 85 to 115 days Sweet Grass County Area, Montana—Part I 217

Major Component Description Doney and similar soils: 2 percent Rock outcrop: 2 percent Fairfield and similar soils Composition: 85 percent Management Geomorphic description: Fan For management information about this map unit, Slope: 8 to 15 percent see appropriate sections in Part II of this publication. Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days 210E—Cabba loam, 15 to 35 percent Surface layer texture: Gravelly loam slopes Drainage class: Well drained Parent material: Loamy alluvium Setting Native plant cover type: Rangeland Available water capacity: Mainly 8.9 inches Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Additional Components Frost-free period: 85 to 115 days Martinsdale and similar soils: 6 percent Major Component Description Tamaneen and similar soils: 5 percent Shawmut and similar soils: 4 percent Cabba and similar soils Composition: 85 percent Management Geomorphic description: For management information about this map unit, • Nose slope summit on hill see appropriate sections in Part II of this publication. • Nose slope backslope on hill • Side slope backslope on hill Slope: 15 to 35 percent 210D—Cabba loam, 2 to 15 percent Elevation: 4,200 to 6,000 feet slopes Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Surface layer texture: Loam Setting Depth to bedrock (paralithic): 10 to 20 inches Drainage class: Well drained Elevation: 4,200 to 6,000 feet Parent material: Loamy residuum weathered from Mean annual precipitation: 15 to 19 inches sandstone and siltstone Frost-free period: 85 to 115 days Native plant cover type: Rangeland Major Component Description Available water capacity: Mainly 2.5 inches Cabba and similar soils Additional Components Composition: 85 percent Vershal and similar soils: 5 percent Geomorphic description: Knoll and plain Castner and similar soils: 3 percent Slope: 2 to 15 percent Doney and similar soils: 3 percent Elevation: 4,200 to 6,000 feet Rock outcrop: 2 percent Effective annual precipitation: 15 to 19 inches Shawmut and similar soils: 2 percent Frost-free period: 85 to 115 days Surface layer texture: Loam Management Depth to bedrock (paralithic): 10 to 20 inches For management information about this map unit, Drainage class: Well drained see appropriate sections in Part II of this publication. Parent material: Loamy residuum weathered from sandstone and siltstone Native plant cover type: Rangeland 213A—Korchea-Fairway-Albicalis loams, Available water capacity: Mainly 2.5 inches channeled, 0 to 4 percent slopes Additional Components Setting Vershal and similar soils: 4 percent Ticell and similar soils: 3 percent Elevation: 3,750 to 5,200 feet Absarokee and similar soils: 2 percent Mean annual precipitation: 10 to 14 inches Amor and similar soils: 2 percent Frost-free period: 95 to 125 days 218 Soil Survey

Major Component Description 215B—Macar loam, calcareous surface, Fairway and similar soils 0 to 4 percent slopes Composition: 45 percent Geomorphic description: Flood plain Setting Slope: 0 to 4 percent Elevation: 4,200 to 6,000 feet Elevation: 3,750 to 5,200 feet Mean annual precipitation: 15 to 19 inches Effective annual precipitation: 10 to 14 inches Frost-free period: 85 to 115 days Frost-free period: 95 to 125 days Surface layer texture: Loam Major Component Description Drainage class: Somewhat poorly drained Macar and similar soils Parent material: Loamy alluvium Composition: 85 percent Native plant cover type: Rangeland Geomorphic description: Tread on stream terrace Flooding: Rare Slope: 0 to 4 percent Water table: Present Elevation: 4,200 to 6,000 feet Available water capacity: Mainly 9.1 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Korchea and similar soils Surface layer texture: Loam Composition: 30 percent Drainage class: Well drained Geomorphic description: Flood-plain step Parent material: Loamy alluvium Slope: 0 to 4 percent Native plant cover type: Rangeland Elevation: 3,750 to 5,200 feet Available water capacity: Mainly 9.4 inches Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Additional Components Surface layer texture: Loam Sagedale and similar soils: 5 percent Drainage class: Well drained Work and similar soils: 4 percent Parent material: Loamy alluvium Shambo and similar soils: 3 percent Native plant cover type: Rangeland Shawmut and similar soils: 3 percent Flooding: Rare Available water capacity: Mainly 10.1 inches Management For management information about this map unit, Albicalis and similar soils see appropriate sections in Part II of this publication. Composition: 15 percent Geomorphic description: Flood plain Slope: 0 to 2 percent 215C—Macar loam, calcareous surface, Elevation: 3,750 to 5,200 feet 4 to 8 percent slopes Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Setting Surface layer texture: Loam Drainage class: Poorly drained Elevation: 4,200 to 6,000 feet Parent material: Fine-loamy alluvium Mean annual precipitation: 15 to 19 inches Native plant cover type: Rangeland Frost-free period: 85 to 115 days Flooding: Rare Major Component Description Water table: Present Available water capacity: Mainly 10.7 inches Macar and similar soils Composition: 85 percent Additional Components Geomorphic description: Fan Kobase and similar soils: 5 percent Slope: 4 to 8 percent Kremlin and similar soils: 5 percent Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Management Frost-free period: 85 to 115 days For management information about this map unit, Surface layer texture: Loam see appropriate sections in Part II of this publication. Drainage class: Well drained Sweet Grass County Area, Montana—Part I 219

Parent material: Loamy alluvium Major Component Description Native plant cover type: Rangeland Clunton and similar soils Available water capacity: Mainly 9.4 inches Composition: 90 percent Additional Components Geomorphic description: Depression and flood plain Slope: 0 to 2 percent Shambo and similar soils: 7 percent Elevation: 3,750 to 6,000 feet Sagedale and similar soils: 5 percent Effective annual precipitation: 10 to 19 inches Shawmut and similar soils: 3 percent Frost-free period: 85 to 125 days Management Surface layer texture: Muck Drainage class: Very poorly drained For management information about this map unit, Parent material: Fine-loamy alluvium over sandy and see appropriate sections in Part II of this publication. gravelly alluvium Native plant cover type: Rangeland Flooding: Frequent 215D—Macar loam, 8 to 15 percent slopes Water table: Present Ponding duration: Brief Setting Available water capacity: Mainly 10.2 inches Elevation: 4,200 to 6,000 feet Additional Components Mean annual precipitation: 15 to 19 inches Fairway and similar soils: 5 percent Frost-free period: 85 to 115 days Soapcreek and similar soils: 5 percent Major Component Description Management Macar and similar soils For management information about this map unit, Composition: 85 percent see appropriate sections in Part II of this publication. Geomorphic description: Fan Slope: 8 to 15 percent Elevation: 4,200 to 6,000 feet 217A—Korchea loam, 0 to 2 percent Effective annual precipitation: 15 to 19 inches slopes Frost-free period: 85 to 115 days Surface layer texture: Loam Setting Drainage class: Well drained Parent material: Loamy alluvium Elevation: 4,200 to 6,000 feet Native plant cover type: Rangeland Mean annual precipitation: 15 to 19 inches Available water capacity: Mainly 9.4 inches Frost-free period: 85 to 115 days Additional Components Major Component Description Shambo and similar soils: 8 percent Korchea and similar soils Sagedale and similar soils: 5 percent Composition: 85 percent Linwell and similar soils: 2 percent Geomorphic description: Stream terrace Slope: 0 to 2 percent Management Elevation: 4,200 to 6,000 feet For management information about this map unit, Effective annual precipitation: 15 to 19 inches see appropriate sections in Part II of this publication. Frost-free period: 85 to 115 days Surface layer texture: Loam Drainage class: Well drained 216A—Clunton clay loam, 0 to 2 percent Parent material: Loamy alluvium slopes Native plant cover type: Rangeland Flooding: Rare Available water capacity: Mainly 10.1 inches Setting Additional Components Elevation: 3,750 to 6,000 feet Mean annual precipitation: 10 to 19 inches Fairway and similar soils: 8 percent Frost-free period: 85 to 125 days Shambo and similar soils: 7 percent 220 Soil Survey

Management Slope: 8 to 15 percent Elevation: 4,200 to 6,000 feet For management information about this map unit, Effective annual precipitation: 15 to 19 inches see appropriate sections in Part II of this publication. Frost-free period: 85 to 115 days Surface layer texture: Sandy loam 218C—Breeton sandy loam, 2 to 8 percent Drainage class: Well drained slopes Parent material: Coarse-loamy alluvium Native plant cover type: Rangeland Available water capacity: Mainly 7.9 inches Setting Additional Components Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Farnuf and similar soils: 5 percent Frost-free period: 85 to 115 days Perma and similar soils: 5 percent Winspect and similar soils: 5 percent Major Component Description Management Breeton and similar soils Composition: 85 percent For management information about this map unit, Geomorphic description: Fan see appropriate sections in Part II of this publication. Slope: 2 to 8 percent Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches 219A—Klayent clay loam, 0 to 2 percent Frost-free period: 85 to 115 days slopes Surface layer texture: Sandy loam Drainage class: Well drained Setting Parent material: Coarse-loamy alluvium Elevation: 3,750 to 6,000 feet Native plant cover type: Rangeland Mean annual precipitation: 10 to 19 inches Available water capacity: Mainly 7.9 inches Frost-free period: 85 to 125 days Additional Components Major Component Description Perma and similar soils: 5 percent Klayent and similar soils Turner and similar soils: 4 percent Composition: 85 percent Beaverton and similar soils: 3 percent Geomorphic description: Flood plain Farnuf and similar soils: 3 percent Slope: 0 to 2 percent Management Elevation: 3,750 to 6,000 feet Effective annual precipitation: 10 to 19 inches For management information about this map unit, Frost-free period: 85 to 125 days see appropriate sections in Part II of this publication. Surface layer texture: Clay loam Drainage class: Poorly drained 218D—Breeton sandy loam, Parent material: Clayey alluvium 8 to 15 percent slopes Native plant cover type: Rangeland Flooding: Rare Water table: Present Setting Available water capacity: Mainly 8.5 inches Elevation: 4,200 to 6,000 feet Additional Components Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Lallie and similar soils: 10 percent Fairway and similar soils: 5 percent Major Component Description Management Breeton and similar soils Composition: 85 percent For management information about this map unit, Geomorphic description: Fan see appropriate sections in Part II of this publication. Sweet Grass County Area, Montana—Part I 221

220C—Amor-Work complex, 220D—Amor-Work complex, 2 to 8 percent slopes 8 to 15 percent slopes

Setting Setting Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Major Component Description Major Component Description Amor and similar soils Amor and similar soils Composition: 50 percent Composition: 50 percent Geomorphic description: Plain and swale Geomorphic description: Plain and swale Slope: 2 to 8 percent Slope: 8 to 15 percent Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Surface layer texture: Loam Surface layer texture: Loam Depth to bedrock (paralithic): 20 to 40 inches Depth to bedrock (paralithic): 20 to 40 inches Drainage class: Well drained Drainage class: Well drained Parent material: Loamy residuum weathered from Parent material: Loamy residuum weathered from sandstone and siltstone sandstone and siltstone Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 6.1 inches Available water capacity: Mainly 6.1 inches

Work and similar soils Work and similar soils Composition: 40 percent Composition: 40 percent Geomorphic description: Plain and swale Geomorphic description: Plain and swale Slope: 2 to 8 percent Slope: 8 to 15 percent Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Surface layer texture: Clay loam Surface layer texture: Clay loam Drainage class: Well drained Drainage class: Well drained Parent material: Clayey alluvium Parent material: Clayey alluvium Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 8.6 inches Available water capacity: Mainly 8.6 inches Additional Components Additional Components Cabba and similar soils: 2 percent Cabba and similar soils: 2 percent Castner and similar soils: 2 percent Castner and similar soils: 2 percent Linwell and similar soils: 2 percent Ticell and similar soils: 2 percent Vershal and similar soils: 2 percent Vershal and similar soils: 2 percent Absarokee and similar soils: 1 percent Absarokee and similar soils: 1 percent Winifred and similar soils: 1 percent Winifred and similar soils: 1 percent Management Management For management information about this map unit, For management information about this map unit, see appropriate sections in Part II of this publication. see appropriate sections in Part II of this publication. 222 Soil Survey

221C—Amor-Farnuf loams, 2 to 8 percent 224B—Shambo loam, 0 to 4 percent slopes slopes

Setting Setting Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Major Component Description Major Component Description Shambo and similar soils Amor and similar soils Composition: 85 percent Composition: 50 percent Geomorphic description: Tread on stream terrace Geomorphic description: Plain and swale Slope: 0 to 4 percent Slope: 2 to 8 percent Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Surface layer texture: Loam Surface layer texture: Loam Drainage class: Well drained Depth to bedrock (paralithic): 20 to 40 inches Parent material: Loamy alluvium Drainage class: Well drained Native plant cover type: Rangeland Parent material: Loamy residuum weathered from Available water capacity: Mainly 10.7 inches sandstone and siltstone Native plant cover type: Rangeland Additional Components Available water capacity: Mainly 6.1 inches Linwell and similar soils: 4 percent Sagedale and similar soils: 4 percent Farnuf and similar soils Work and similar soils: 4 percent Composition: 42 percent Fairway and similar soils: 3 percent Geomorphic description: Plain and swale Slope: 2 to 8 percent Management Elevation: 4,200 to 6,000 feet For management information about this map unit, Effective annual precipitation: 15 to 19 inches see appropriate sections in Part II of this publication. Frost-free period: 85 to 115 days Surface layer texture: Loam Drainage class: Well drained 224C—Shambo loam, 4 to 8 percent Parent material: Loamy alluvium slopes Native plant cover type: Rangeland Available water capacity: Mainly 9.6 inches Setting Additional Components Elevation: 4,200 to 6,000 feet Cabba and similar soils: 3 percent Mean annual precipitation: 15 to 19 inches Reedwest and similar soils: 3 percent Frost-free period: 85 to 115 days Work and similar soils: 2 percent Major Component Description Management Shambo and similar soils For management information about this map unit, Composition: 85 percent see appropriate sections in Part II of this publication. Geomorphic description: Fan Sweet Grass County Area, Montana—Part I 223

Slope: 4 to 8 percent Management Elevation: 4,200 to 6,000 feet For management information about this map unit, Effective annual precipitation: 15 to 19 inches see appropriate sections in Part II of this publication. Frost-free period: 85 to 115 days Surface layer texture: Loam Drainage class: Well drained Parent material: Loamy alluvium 225C—Amor-Cabba loams, 2 to 8 percent Native plant cover type: Rangeland slopes Available water capacity: Mainly 10.7 inches Setting Additional Components Elevation: 4,200 to 6,000 feet Farnuf and similar soils: 6 percent Mean annual precipitation: 15 to 19 inches Work and similar soils: 3 percent Frost-free period: 85 to 115 days Fairfield and similar soils: 2 percent Linwell and similar soils: 2 percent Major Component Description Roy and similar soils: 2 percent Amor and similar soils Management Composition: 50 percent Geomorphic description: Plain and swale For management information about this map unit, Slope: 2 to 8 percent see appropriate sections in Part II of this publication. Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches 224D—Shambo loam, 8 to 15 percent Frost-free period: 85 to 115 days slopes Surface layer texture: Loam Depth to bedrock (paralithic): 20 to 40 inches Drainage class: Well drained Setting Parent material: Loamy residuum weathered from Elevation: 4,200 to 6,000 feet sandstone and siltstone Mean annual precipitation: 15 to 19 inches Native plant cover type: Rangeland Frost-free period: 85 to 115 days Available water capacity: Mainly 6.1 inches Major Component Description Cabba and similar soils Shambo and similar soils Composition: 40 percent Composition: 85 percent Geomorphic description: Knoll and plain Geomorphic description: Fan Slope: 2 to 8 percent Slope: 8 to 15 percent Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Surface layer texture: Loam Surface layer texture: Loam Depth to bedrock (paralithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained Parent material: Loamy alluvium Parent material: Loamy residuum weathered from Native plant cover type: Rangeland sandstone and siltstone Available water capacity: Mainly 10.7 inches Native plant cover type: Rangeland Available water capacity: Mainly 2.5 inches Additional Components Additional Components Farnuf and similar soils: 7 percent Linwell and similar soils: 3 percent Castner and similar soils: 4 percent Shawmut and similar soils: 3 percent Reedwest and similar soils: 3 percent Bowery and similar soils: 2 percent Ticell and similar soils: 3 percent 224 Soil Survey

Management 227F—Cabba, moist-Rock outcrop For management information about this map unit, complex, 15 to 60 percent slopes see appropriate sections in Part II of this publication. Setting Field investigation intensity: Order 2 225D—Amor-Cabba loams, Elevation: 3,900 to 6,000 feet 8 to 15 percent slopes Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Setting Major Component Description Elevation: 4,200 to 6,000 feet Cabba and similar soils Mean annual precipitation: 15 to 19 inches Composition: 70 percent Frost-free period: 85 to 115 days Geomorphic description: • Nose slope backslope on escarpment Major Component Description • Nose slope summit on escarpment • Side slope backslope on escarpment Amor and similar soils Slope: 15 to 60 percent Composition: 50 percent Elevation: 3,900 to 6,000 feet Geomorphic description: Plain and swale Effective annual precipitation: 15 to 19 inches Slope: 8 to 15 percent Frost-free period: 85 to 115 days Elevation: 4,200 to 6,000 feet Surface layer texture: Loam Effective annual precipitation: 15 to 19 inches Depth to bedrock (paralithic): 10 to 20 inches Frost-free period: 85 to 115 days Drainage class: Well drained Surface layer texture: Loam Parent material: Loamy residuum weathered from Depth to bedrock (paralithic): 20 to 40 inches sandstone and siltstone Drainage class: Well drained Native plant cover type: Forestland Parent material: Loamy residuum weathered from Available water capacity: Mainly 2.0 inches sandstone and siltstone Native plant cover type: Rangeland Available water capacity: Mainly 6.1 inches Rock outcrop Composition: 20 percent Cabba and similar soils Definition: Rock outcrop consists mainly of areas of Composition: 40 percent exposed hard bedrock. Geomorphic description: Knoll and plain Geomorphic description: Escarpment Slope: 8 to 15 percent Elevation: 4,200 to 6,000 feet Additional Components Effective annual precipitation: 15 to 19 inches Castner and similar soils: 3 percent Frost-free period: 85 to 115 days Vershal and similar soils: 3 percent Surface layer texture: Loam Doney and similar soils: 2 percent Depth to bedrock (paralithic): 10 to 20 inches Wayden and similar soils: 2 percent Drainage class: Well drained Parent material: Loamy residuum weathered from Management sandstone and siltstone For management information about this map unit, Native plant cover type: Rangeland see appropriate sections in Part II of this publication. Available water capacity: Mainly 2.5 inches Additional Components 229C—Absarokee-Cabba loams, Castner and similar soils: 4 percent 2 to 8 percent slopes Reedwest and similar soils: 3 percent Ticell and similar soils: 3 percent Setting Management Elevation: 4,200 to 6,000 feet For management information about this map unit, Mean annual precipitation: 15 to 19 inches see appropriate sections in Part II of this publication. Frost-free period: 85 to 115 days Sweet Grass County Area, Montana—Part I 225

Major Component Description Major Component Description Absarokee and similar soils Absarokee and similar soils Composition: 50 percent Composition: 50 percent Geomorphic description: Plain and swale Geomorphic description: Plain and swale Slope: 2 to 8 percent Slope: 8 to 15 percent Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Surface layer texture: Loam Surface layer texture: Loam Depth to bedrock (lithic): 20 to 40 inches Depth to bedrock (lithic): 20 to 40 inches Drainage class: Well drained Drainage class: Well drained Parent material: Silty and clayey residuum weathered Parent material: Silty and clayey residuum weathered from sandstone and shale from sandstone and shale Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 4.1 inches Available water capacity: Mainly 4.1 inches

Cabba and similar soils Cabba and similar soils Composition: 40 percent Composition: 40 percent Geomorphic description: Knoll and plain Geomorphic description: Knoll and plain Slope: 2 to 8 percent Slope: 8 to 15 percent Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Surface layer texture: Loam Surface layer texture: Loam Depth to bedrock (paralithic): 10 to 20 inches Depth to bedrock (paralithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained Parent material: Loamy residuum weathered from Parent material: Loamy residuum weathered from sandstone and siltstone sandstone and siltstone Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 2.5 inches Available water capacity: Mainly 2.5 inches Additional Components Additional Components Winifred and similar soils: 4 percent Castner and similar soils: 2 percent Castner and similar soils: 3 percent Linwell and similar soils: 2 percent Winifred and similar soils: 3 percent Ticell and similar soils: 2 percent Linwell and similar soils: 2 percent Ticell and similar soils: 2 percent Management For management information about this map unit, Management see appropriate sections in Part II of this publication. For management information about this map unit, see appropriate sections in Part II of this publication. 229D—Absarokee-Cabba loams, 8 to 15 percent slopes 230B—Farnuf loam, 0 to 4 percent slopes Setting Setting Field investigation intensity: Order 2 Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days 226 Soil Survey

Major Component Description Management Farnuf and similar soils For management information about this map unit, Composition: 85 percent see appropriate sections in Part II of this publication. Geomorphic description: Tread on terrace Slope: 0 to 4 percent Elevation: 4,200 to 6,000 feet 230D—Farnuf loam, 8 to 15 percent Effective annual precipitation: 15 to 19 inches slopes Frost-free period: 85 to 115 days Surface layer texture: Loam Setting Drainage class: Well drained Elevation: 4,200 to 6,000 feet Parent material: Loamy alluvium Mean annual precipitation: 15 to 19 inches Native plant cover type: Rangeland Frost-free period: 85 to 115 days Available water capacity: Mainly 9.6 inches Major Component Description Additional Components Farnuf and similar soils Shambo and similar soils: 5 percent Composition: 85 percent Work and similar soils: 4 percent Geomorphic description: Fan Absarokee and similar soils: 3 percent Slope: 8 to 15 percent Reedwest and similar soils: 3 percent Elevation: 4,200 to 6,000 feet Management Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days For management information about this map unit, Surface layer texture: Loam see appropriate sections in Part II of this publication. Drainage class: Well drained Parent material: Loamy alluvium Native plant cover type: Rangeland 230C—Farnuf loam, 4 to 8 percent slopes Available water capacity: Mainly 9.6 inches Additional Components Setting Winspect and similar soils: 6 percent Elevation: 4,200 to 6,000 feet Bowery and similar soils: 5 percent Mean annual precipitation: 15 to 19 inches Breeton and similar soils: 3 percent Frost-free period: 85 to 115 days Work and similar soils: 1 percent Major Component Description Management Farnuf and similar soils For management information about this map unit, Composition: 85 percent see appropriate sections in Part II of this publication. Geomorphic description: Fan Slope: 4 to 8 percent Elevation: 4,200 to 6,000 feet 231C—Doney-Cabba loams, 2 to 8 percent Effective annual precipitation: 15 to 19 inches slopes Frost-free period: 85 to 115 days Surface layer texture: Loam Setting Drainage class: Well drained Parent material: Loamy alluvium Field investigation intensity: Order 2 Native plant cover type: Rangeland Elevation: 4,200 to 6,000 feet Available water capacity: Mainly 9.6 inches Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Additional Components Major Component Description Beaverton and similar soils: 5 percent Shambo and similar soils: 4 percent Doney and similar soils Turner and similar soils: 3 percent Composition: 50 percent Work and similar soils: 3 percent Geomorphic description: Plain and swale Sweet Grass County Area, Montana—Part I 227

Slope: 2 to 8 percent Frost-free period: 85 to 115 days Elevation: 4,200 to 6,000 feet Surface layer texture: Loam Effective annual precipitation: 15 to 19 inches Depth to bedrock (paralithic): 20 to 40 inches Frost-free period: 85 to 115 days Drainage class: Well drained Surface layer texture: Loam Parent material: Loamy residuum weathered from Depth to bedrock (paralithic): 20 to 40 inches sandstone and siltstone Drainage class: Well drained Native plant cover type: Rangeland Parent material: Loamy residuum weathered from Available water capacity: Mainly 5.4 inches sandstone and siltstone Native plant cover type: Rangeland Cabba and similar soils Available water capacity: Mainly 5.4 inches Composition: 40 percent Geomorphic description: Knoll and plain Cabba and similar soils Slope: 8 to 15 percent Composition: 40 percent Elevation: 4,200 to 6,000 feet Geomorphic description: Knoll and plain Effective annual precipitation: 15 to 19 inches Slope: 2 to 8 percent Frost-free period: 85 to 115 days Elevation: 4,200 to 6,000 feet Surface layer texture: Loam Effective annual precipitation: 15 to 19 inches Depth to bedrock (paralithic): 10 to 20 inches Frost-free period: 85 to 115 days Drainage class: Well drained Surface layer texture: Loam Parent material: Loamy residuum weathered from Depth to bedrock (paralithic): 10 to 20 inches sandstone and siltstone Drainage class: Well drained Native plant cover type: Rangeland Parent material: Loamy residuum weathered from Available water capacity: Mainly 2.5 inches sandstone and siltstone Additional Components Native plant cover type: Rangeland Available water capacity: Mainly 2.5 inches Sagedale and similar soils: 4 percent Castner and similar soils: 3 percent Additional Components Macar and similar soils: 3 percent Castner and similar soils: 3 percent Management Wayden and similar soils: 3 percent Ticell and similar soils: 2 percent For management information about this map unit, Reedwest and similar soils: 1 percent see appropriate sections in Part II of this publication. Sagedale and similar soils: 1 percent Management 232B—Work loam, 0 to 4 percent slopes For management information about this map unit, see appropriate sections in Part II of this publication. Setting Elevation: 4,200 to 6,000 feet 231D—Doney-Cabba loams, Mean annual precipitation: 15 to 19 inches 8 to 15 percent slopes Frost-free period: 85 to 115 days Major Component Description Setting Work and similar soils Elevation: 4,200 to 6,000 feet Composition: 85 percent Mean annual precipitation: 15 to 19 inches Geomorphic description: Tread on terrace Frost-free period: 85 to 115 days Slope: 0 to 4 percent Elevation: 4,200 to 6,000 feet Major Component Description Effective annual precipitation: 15 to 19 inches Doney and similar soils Frost-free period: 85 to 115 days Composition: 50 percent Surface layer texture: Loam Geomorphic description: Plain and swale Drainage class: Well drained Slope: 8 to 15 percent Parent material: Clayey alluvium Elevation: 4,200 to 6,000 feet Native plant cover type: Rangeland Effective annual precipitation: 15 to 19 inches Available water capacity: Mainly 8.7 inches 228 Soil Survey

Additional Components Major Component Description Absarokee and similar soils: 3 percent Verson and similar soils Castner and similar soils: 3 percent Composition: 89 percent Farnuf and similar soils: 3 percent Geomorphic description: Tread on terrace Linwell and similar soils: 3 percent Slope: 0 to 4 percent Tamaneen and similar soils: 3 percent Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Management Frost-free period: 95 to 125 days For management information about this map unit, Surface layer texture: Loam see appropriate sections in Part II of this publication. Drainage class: Well drained Parent material: Clayey over gravelly alluvium Native plant cover type: Rangeland 232C—Work loam, 4 to 8 percent slopes Available water capacity: Mainly 6.3 inches Additional Components Setting Ethridge and similar soils: 6 percent Elevation: 4,200 to 6,000 feet Radersburg and similar soils: 5 percent Mean annual precipitation: 15 to 19 inches Management Frost-free period: 85 to 115 days For management information about this map unit, Major Component Description see appropriate sections in Part II of this publication. Work and similar soils Composition: 85 percent Geomorphic description: Fan 236C—Verson loam, 4 to 8 percent slopes Slope: 4 to 8 percent Elevation: 4,200 to 6,000 feet Setting Effective annual precipitation: 15 to 19 inches Elevation: 3,750 to 5,200 feet Frost-free period: 85 to 115 days Mean annual precipitation: 10 to 14 inches Surface layer texture: Loam Frost-free period: 95 to 125 days Drainage class: Well drained Parent material: Clayey alluvium Major Component Description Native plant cover type: Rangeland Verson and similar soils Available water capacity: Mainly 8.7 inches Composition: 85 percent Additional Components Geomorphic description: Fan Slope: 4 to 8 percent Linwell and similar soils: 9 percent Elevation: 3,750 to 5,200 feet Shawmut and similar soils: 4 percent Effective annual precipitation: 10 to 14 inches Shambo and similar soils: 2 percent Frost-free period: 95 to 125 days Management Surface layer texture: Loam Drainage class: Well drained For management information about this map unit, Parent material: Clayey over gravelly alluvium see appropriate sections in Part II of this publication. Native plant cover type: Rangeland Available water capacity: Mainly 5.6 inches 236B—Verson loam, 0 to 4 percent slopes Additional Components Sieben and similar soils: 4 percent Setting Ethridge and similar soils: 3 percent Elevation: 3,750 to 5,200 feet Evanston and similar soils: 3 percent Mean annual precipitation: 10 to 14 inches Radersburg and similar soils: 3 percent Frost-free period: 95 to 125 days Kremlin and similar soils: 2 percent Sweet Grass County Area, Montana—Part I 229

Management Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches For management information about this map unit, Frost-free period: 85 to 115 days see appropriate sections in Part II of this publication. Surface layer texture: Clay loam Drainage class: Well drained 237B—Thibadeau loam, saline, Parent material: Clayey alluvium weathered from 0 to 4 percent slopes shale and siltstone Native plant cover type: Rangeland Available water capacity: Mainly 9.6 inches Setting Elevation: 3,750 to 5,200 feet Cabba and similar soils Mean annual precipitation: 10 to 14 inches Composition: 30 percent Frost-free period: 95 to 125 days Geomorphic description: Knoll and plain Slope: 2 to 8 percent Major Component Description Elevation: 4,200 to 6,000 feet Thibadeau and similar soils Effective annual precipitation: 15 to 19 inches Composition: 85 percent Frost-free period: 85 to 115 days Geomorphic description: Flood plain Surface layer texture: Loam Slope: 0 to 4 percent Depth to bedrock (paralithic): 10 to 20 inches Elevation: 3,750 to 5,200 feet Drainage class: Well drained Effective annual precipitation: 10 to 14 inches Parent material: Loamy residuum weathered from Frost-free period: 95 to 125 days sandstone and siltstone Surface layer texture: Loam Native plant cover type: Rangeland Drainage class: Moderately well drained Available water capacity: Mainly 2.5 inches Parent material: Loamy alluvium Additional Components Native plant cover type: Rangeland Flooding: Rare Doney and similar soils: 4 percent Water table: Present Wayden and similar soils: 4 percent Salt affected: Saline within 30 inches Castner and similar soils: 2 percent Available water capacity: Mainly 6.5 inches Management Additional Components For management information about this map unit, Absher and similar soils: 5 percent see appropriate sections in Part II of this publication. Lallie and similar soils: 5 percent Ledger and similar soils: 5 percent 238F—Sagedale-Cabba complex, Management 8 to 35 percent slopes For management information about this map unit, see appropriate sections in Part II of this publication. Setting Elevation: 4,200 to 6,000 feet 238C—Sagedale-Cabba complex, Mean annual precipitation: 15 to 19 inches 2 to 8 percent slopes Frost-free period: 85 to 115 days Major Component Description Setting Sagedale and similar soils Elevation: 4,200 to 6,000 feet Composition: 60 percent Mean annual precipitation: 15 to 19 inches Geomorphic description: Base slope on escarpment Frost-free period: 85 to 115 days and fan Slope: 8 to 35 percent Major Component Description Elevation: 4,200 to 6,000 feet Sagedale and similar soils Effective annual precipitation: 15 to 19 inches Composition: 60 percent Frost-free period: 85 to 115 days Geomorphic description: Plain and swale Surface layer texture: Clay loam Slope: 2 to 8 percent Drainage class: Well drained 230 Soil Survey

Parent material: Clayey alluvium weathered from Surface layer texture: Gravelly loam shale and siltstone Drainage class: Well drained Native plant cover type: Rangeland Parent material: Gravelly alluvium Available water capacity: Mainly 9.6 inches Native plant cover type: Rangeland Available water capacity: Mainly 4.4 inches Cabba and similar soils Additional Components Composition: 30 percent Geomorphic description: Kremlin and similar soils: 5 percent • Nose slope backslope on escarpment Sieben and similar soils: 5 percent • Nose slope summit on escarpment Yamacall and similar soils: 5 percent • Side slope backslope on escarpment Management Slope: 8 to 35 percent Elevation: 4,200 to 6,000 feet For management information about this map unit, Effective annual precipitation: 15 to 19 inches see appropriate sections in Part II of this publication. Frost-free period: 85 to 115 days Surface layer texture: Loam Depth to bedrock (paralithic): 10 to 20 inches 241D—Yawdim clay loam, 2 to 15 percent Drainage class: Well drained slopes Parent material: Loamy residuum weathered from sandstone and siltstone Setting Native plant cover type: Rangeland Elevation: 3,750 to 5,200 feet Available water capacity: Mainly 2.0 inches Mean annual precipitation: 10 to 14 inches Additional Components Frost-free period: 95 to 125 days Doney and similar soils: 4 percent Major Component Description Wayden and similar soils: 3 percent Yawdim and similar soils Castner and similar soils: 2 percent Composition: 85 percent Rock outcrop: 1 percent Geomorphic description: Knoll and plain Management Slope: 2 to 15 percent Elevation: 3,750 to 5,200 feet For management information about this map unit, Effective annual precipitation: 10 to 14 inches see appropriate sections in Part II of this publication. Frost-free period: 95 to 125 days Surface layer texture: Clay loam 239C—Sixbeacon gravelly loam, Depth to bedrock (paralithic): 10 to 20 inches 2 to 8 percent slopes Drainage class: Well drained Parent material: Clayey residuum weathered from calcareous shale Setting Native plant cover type: Rangeland Elevation: 3,750 to 5,200 feet Available water capacity: Mainly 2.4 inches Mean annual precipitation: 10 to 14 inches Additional Components Frost-free period: 95 to 125 days Megonot and similar soils: 4 percent Major Component Description Cabbart and similar soils: 3 percent Sixbeacon and similar soils Delpoint and similar soils: 3 percent Composition: 85 percent Rentsac and similar soils: 3 percent Geomorphic description: Fan Rock outcrop: 2 percent Slope: 2 to 8 percent Management Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches For management information about this map unit, Frost-free period: 95 to 125 days see appropriate sections in Part II of this publication. Sweet Grass County Area, Montana—Part I 231

245C—Lonna silt loam, 2 to 8 percent Drainage class: Somewhat poorly drained slopes Parent material: Clayey alluvium Native plant cover type: Rangeland Flooding: Rare Setting Water table: Present Elevation: 3,750 to 5,200 feet Available water capacity: Mainly 9.4 inches Mean annual precipitation: 10 to 14 inches Additional Components Frost-free period: 95 to 125 days Fairway and similar soils: 5 percent Major Component Description Lallie and similar soils: 5 percent Lonna and similar soils Meadowcreek and similar soils: 3 percent Composition: 85 percent Richey and similar soils: 2 percent Geomorphic description: Fan Management Slope: 2 to 8 percent Elevation: 3,750 to 5,200 feet For management information about this map unit, Effective annual precipitation: 10 to 14 inches see appropriate sections in Part II of this publication. Frost-free period: 95 to 125 days Surface layer texture: Silt loam Drainage class: Well drained 250A—Lallie family, silty clay, Parent material: Silty alluvium 0 to 2 percent slopes Native plant cover type: Rangeland Salt affected: Saline within 30 inches Setting Sodium affected: Sodic within 30 inches Elevation: 3,750 to 6,000 feet Available water capacity: Mainly 9.0 inches Mean annual precipitation: 10 to 19 inches Additional Components Frost-free period: 85 to 125 days Ethridge and similar soils: 8 percent Major Component Description Yamacall and similar soils: 7 percent Lallie and similar soils Management Composition: 85 percent Geomorphic description: Flood plain For management information about this map unit, Slope: 0 to 2 percent see appropriate sections in Part II of this publication. Elevation: 3,750 to 6,000 feet Effective annual precipitation: 10 to 19 inches 249B—Soapcreek clay loam, Frost-free period: 85 to 125 days 0 to 2 percent slopes Surface layer texture: Silty clay Drainage class: Poorly drained Parent material: Clayey alluvium Setting Native plant cover type: Rangeland Elevation: 3,750 to 5,200 feet Flooding: Frequent Mean annual precipitation: 10 to 14 inches Water table: Present Frost-free period: 95 to 125 days Salt affected: Saline within 30 inches Available water capacity: Mainly 9.3 inches Major Component Description Additional Components Soapcreek and similar soils Composition: 85 percent Fairway and similar soils: 5 percent Geomorphic description: Flood plain Soapcreek and similar soils: 5 percent Slope: 0 to 2 percent Swampcreek and similar soils: 5 percent Elevation: 3,750 to 5,200 feet Management Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days For management information about this map unit, Surface layer texture: Clay loam see appropriate sections in Part II of this publication. 232 Soil Survey

251B—Radersburg gravelly loam, Native plant cover type: Rangeland 0 to 4 percent slopes Available water capacity: Mainly 4.5 inches Swampcreek and similar soils Setting Composition: 40 percent Elevation: 3,750 to 5,200 feet Geomorphic description: Swale and tread on terrace Mean annual precipitation: 10 to 14 inches Slope: 0 to 4 percent Frost-free period: 95 to 125 days Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Major Component Description Frost-free period: 85 to 115 days Radersburg and similar soils Surface layer texture: Gravelly sandy clay loam Composition: 85 percent Drainage class: Poorly drained Geomorphic description: Tread on terrace Parent material: Loamy over gravelly alluvium Slope: 0 to 4 percent Native plant cover type: Rangeland Elevation: 3,750 to 5,200 feet Flooding: Rare Effective annual precipitation: 10 to 14 inches Water table: Present Frost-free period: 95 to 125 days Available water capacity: Mainly 4.6 inches Surface layer texture: Gravelly loam Additional Components Drainage class: Well drained Parent material: Gravelly alluvium Beaverton and similar soils: 5 percent Native plant cover type: Rangeland Newtman and similar soils: 5 percent Available water capacity: Mainly 7.4 inches Management Additional Components For management information about this map unit, Verson and similar soils: 5 percent see appropriate sections in Part II of this publication. Ethridge and similar soils: 4 percent Sieben and similar soils: 4 percent Tanna and similar soils: 2 percent 253C—Reedwest-Castner complex, 2 to 8 percent slopes Management For management information about this map unit, Setting see appropriate sections in Part II of this publication. Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days 252B—Roy-Swampcreek complex, 0 to 4 percent slopes Major Component Description Reedwest and similar soils Composition: 60 percent Setting Geomorphic description: Plain and swale Elevation: 4,200 to 6,000 feet Slope: 2 to 8 percent Mean annual precipitation: 15 to 19 inches Elevation: 4,200 to 6,000 feet Frost-free period: 85 to 115 days Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Major Component Description Surface layer texture: Loam Roy and similar soils Depth to bedrock (paralithic): 20 to 40 inches Composition: 50 percent Drainage class: Well drained Geomorphic description: Tread on terrace Parent material: Loamy residuum weathered from Slope: 0 to 4 percent sandstone and siltstone Elevation: 4,200 to 6,000 feet Native plant cover type: Rangeland Effective annual precipitation: 15 to 19 inches Available water capacity: Mainly 4.6 inches Frost-free period: 85 to 115 days Surface layer texture: Gravelly clay loam Castner and similar soils Drainage class: Well drained Composition: 30 percent Parent material: Gravelly glaciofluvial deposits Geomorphic description: Knoll and plain Sweet Grass County Area, Montana—Part I 233

Slope: 2 to 8 percent Effective annual precipitation: 15 to 19 inches Elevation: 4,200 to 6,000 feet Frost-free period: 85 to 115 days Effective annual precipitation: 15 to 19 inches Surface layer texture: Channery loam Frost-free period: 85 to 115 days Depth to bedrock (lithic): 10 to 20 inches Surface layer texture: Channery loam Drainage class: Well drained Depth to bedrock (lithic): 10 to 20 inches Parent material: Residuum weathered from Drainage class: Well drained sandstone Parent material: Residuum weathered from Native plant cover type: Rangeland sandstone Available water capacity: Mainly 1.6 inches Native plant cover type: Rangeland Additional Components Available water capacity: Mainly 1.6 inches Farnuf and similar soils: 6 percent Additional Components Beenom and similar soils: 2 percent Cabba and similar soils: 3 percent Ticell and similar soils: 2 percent Vershal and similar soils: 3 percent Management Ticell and similar soils: 2 percent Absarokee and similar soils: 1 percent For management information about this map unit, Work and similar soils: 1 percent see appropriate sections in Part II of this publication. Management For management information about this map unit, 253E—Reedwest-Castner complex, see appropriate sections in Part II of this publication. 15 to 35 percent slopes

Setting 253D—Reedwest-Castner complex, 8 to 15 percent slopes Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Setting Major Component Description Field investigation intensity: Order 2 Elevation: 4,200 to 6,000 feet Reedwest and similar soils Mean annual precipitation: 15 to 19 inches Composition: 50 percent Frost-free period: 85 to 115 days Geomorphic description: • Base slope backslope on hill Major Component Description • Base slope footslope on hill Reedwest and similar soils • Side slope backslope on hill Composition: 50 percent Slope: 15 to 35 percent Geomorphic description: Plain and swale Elevation: 4,200 to 6,000 feet Slope: 8 to 15 percent Effective annual precipitation: 15 to 19 inches Elevation: 4,200 to 6,000 feet Frost-free period: 85 to 115 days Effective annual precipitation: 15 to 19 inches Surface layer texture: Loam Frost-free period: 85 to 115 days Depth to bedrock (paralithic): 20 to 40 inches Surface layer texture: Loam Drainage class: Well drained Depth to bedrock (paralithic): 20 to 40 inches Parent material: Loamy residuum weathered from Drainage class: Well drained sandstone and siltstone Parent material: Loamy residuum weathered from Native plant cover type: Rangeland sandstone and siltstone Available water capacity: Mainly 4.6 inches Native plant cover type: Rangeland Available water capacity: Mainly 4.6 inches Castner and similar soils Composition: 43 percent Castner and similar soils Geomorphic description: Composition: 40 percent • Nose slope summit on hill Geomorphic description: Knoll and plain • Nose slope shoulder on hill Slope: 8 to 15 percent Slope: 15 to 35 percent Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet 234 Soil Survey

Effective annual precipitation: 15 to 19 inches Management Frost-free period: 85 to 115 days For management information about this map unit, Surface layer texture: Channery loam see appropriate sections in Part II of this publication. Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Parent material: Residuum weathered from sandstone 255B—Thibadeau, saline-Absher family Native plant cover type: Rangeland complex, 0 to 8 percent slopes Available water capacity: Mainly 1.4 inches Setting Additional Components Elevation: 3,750 to 5,200 feet Farnuf and similar soils: 4 percent Mean annual precipitation: 10 to 14 inches Ticell and similar soils: 3 percent Frost-free period: 95 to 125 days Management Major Component Description For management information about this map unit, Thibadeau and similar soils see appropriate sections in Part II of this publication. Composition: 50 percent Geomorphic description: Flood plain 254C—Winifred clay loam, 2 to 8 percent Slope: 0 to 4 percent slopes Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Setting Surface layer texture: Loam Elevation: 4,200 to 6,000 feet Drainage class: Moderately well drained Mean annual precipitation: 15 to 19 inches Parent material: Loamy alluvium Frost-free period: 85 to 115 days Native plant cover type: Rangeland Flooding: Occasional Major Component Description Water table: Present Winifred and similar soils Salt affected: Saline within 30 inches Composition: 85 percent Available water capacity: Mainly 6.5 inches Geomorphic description: Plain and swale Slope: 2 to 8 percent Absher and similar soils Elevation: 4,200 to 6,000 feet Composition: 40 percent Effective annual precipitation: 15 to 19 inches Geomorphic description: Stream terrace Frost-free period: 85 to 115 days Slope: 0 to 4 percent Surface layer texture: Clay loam Elevation: 3,750 to 5,200 feet Depth to bedrock (paralithic): 20 to 40 inches Effective annual precipitation: 10 to 14 inches Drainage class: Well drained Frost-free period: 95 to 125 days Parent material: Clayey residuum weathered from Surface layer texture: Clay sandstone and shale Drainage class: Somewhat poorly drained Native plant cover type: Rangeland Parent material: Silty and clayey alluvium Available water capacity: Mainly 5.3 inches Native plant cover type: Rangeland Water table: Present Additional Components Salt affected: Saline within 30 inches Cabba and similar soils: 4 percent Sodium affected: Sodic within 30 inches Wayden and similar soils: 3 percent Available water capacity: Mainly 3.8 inches Absarokee and similar soils: 2 percent Additional Components Amor and similar soils: 2 percent Doney and similar soils: 2 percent Albicalis and similar soils: 5 percent Linwell and similar soils: 2 percent Gerdrum and similar soils: 5 percent Sweet Grass County Area, Montana—Part I 235

Management Management For management information about this map unit, For management information about this map unit, see appropriate sections in Part II of this publication. see appropriate sections in Part II of this publication.

256F—Sixbeacon-Reedpoint complex, 257B—Absher-Bigsag families, clays, 15 to 60 percent slopes 0 to 4 percent slopes

Setting Setting Elevation: 3,750 to 5,200 feet Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Mean annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Frost-free period: 95 to 125 days Major Component Description Major Component Description Sixbeacon and similar soils Absher and similar soils Composition: 60 percent Composition: 60 percent Geomorphic description: Base slope on escarpment Geomorphic description: Flood plain and fan Slope: 0 to 4 percent Slope: 15 to 60 percent Elevation: 3,750 to 5,200 feet Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Frost-free period: 95 to 125 days Surface layer texture: Clay Surface layer texture: Gravelly loam Drainage class: Somewhat poorly drained Drainage class: Well drained Parent material: Silty and clayey alluvium Parent material: Gravelly alluvium Native plant cover type: Rangeland Native plant cover type: Rangeland Water table: Present Available water capacity: Mainly 4.4 inches Salt affected: Saline within 30 inches Sodium affected: Sodic within 30 inches Available water capacity: Mainly 3.8 inches Reedpoint and similar soils Composition: 30 percent Bigsag and similar soils Geomorphic description: Composition: 25 percent • Nose slope summit on escarpment Geomorphic description: Flood plain • Nose slope shoulder on escarpment Slope: 2 to 4 percent Slope: 15 to 60 percent Elevation: 3,750 to 5,200 feet Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Frost-free period: 95 to 125 days Surface layer texture: Clay Surface layer texture: Very channery loam Drainage class: Very poorly drained Depth to bedrock (lithic): 4 to 10 inches Parent material: Clayey alluvium weathered from Drainage class: Well drained sandstone and shale Parent material: Residuum weathered from Native plant cover type: Rangeland sandstone Water table: Present Native plant cover type: Rangeland Ponding duration: Long Available water capacity: Mainly 0.4 inches Salt affected: Saline within 30 inches Available water capacity: Mainly 7.8 inches Additional Components Additional Components Verson and similar soils: 4 percent Rentsac and similar soils: 3 percent Havre and similar soils: 10 percent Yawdim and similar soils: 3 percent Yamacall and similar soils: 5 percent 236 Soil Survey

Management Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches For management information about this map unit, Frost-free period: 85 to 115 days see appropriate sections in Part II of this publication. Surface layer texture: Clay Depth to bedrock (paralithic): 10 to 20 inches 259D—Wayden clay, 2 to 15 percent Drainage class: Well drained slopes Parent material: Clayey residuum weathered from shale and siltstone Native plant cover type: Rangeland Setting Available water capacity: Mainly 2.7 inches Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Doney and similar soils Frost-free period: 85 to 115 days Composition: 40 percent Geomorphic description: Plain and swale Major Component Description Slope: 2 to 8 percent Wayden and similar soils Elevation: 4,200 to 6,000 feet Composition: 85 percent Effective annual precipitation: 15 to 19 inches Geomorphic description: Knoll and plain Frost-free period: 85 to 115 days Slope: 2 to 15 percent Surface layer texture: Loam Elevation: 4,200 to 6,000 feet Depth to bedrock (paralithic): 20 to 40 inches Effective annual precipitation: 15 to 19 inches Drainage class: Well drained Frost-free period: 85 to 115 days Parent material: Loamy residuum weathered from Surface layer texture: Clay sandstone and siltstone Depth to bedrock (paralithic): 10 to 20 inches Native plant cover type: Rangeland Drainage class: Well drained Available water capacity: Mainly 5.4 inches Parent material: Clayey residuum weathered from Additional Components shale and siltstone Native plant cover type: Rangeland Cabba and similar soils: 5 percent Available water capacity: Mainly 2.7 inches Sagedale and similar soils: 5 percent Additional Components Management Cabba and similar soils: 5 percent For management information about this map unit, Sagedale and similar soils: 5 percent see appropriate sections in Part II of this publication. Winifred and similar soils: 3 percent Castner and similar soils: 2 percent 261C—Absarokee-Wayden complex, Management 2 to 8 percent slopes For management information about this map unit, see appropriate sections in Part II of this publication. Setting Elevation: 4,200 to 6,000 feet 260C—Wayden-Doney complex, Mean annual precipitation: 15 to 19 inches 2 to 8 percent slopes Frost-free period: 85 to 115 days Major Component Description Setting Absarokee and similar soils Elevation: 4,200 to 6,000 feet Composition: 50 percent Mean annual precipitation: 15 to 19 inches Geomorphic description: Plain and swale Frost-free period: 85 to 115 days Slope: 2 to 8 percent Elevation: 4,200 to 6,000 feet Major Component Description Effective annual precipitation: 15 to 19 inches Wayden and similar soils Frost-free period: 85 to 115 days Composition: 50 percent Surface layer texture: Clay loam Geomorphic description: Knoll and plain Depth to bedrock (lithic): 20 to 40 inches Slope: 2 to 8 percent Drainage class: Well drained Sweet Grass County Area, Montana—Part I 237

Parent material: Silty and clayey residuum weathered Parent material: Clayey residuum weathered from from sandstone and shale shale and siltstone Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 4.1 inches Available water capacity: Mainly 2.7 inches

Wayden and similar soils Castner and similar soils Composition: 40 percent Composition: 30 percent Geomorphic description: Knoll and plain Geomorphic description: Knoll and plain Slope: 2 to 8 percent Slope: 2 to 15 percent Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Surface layer texture: Clay Surface layer texture: Channery loam Depth to bedrock (paralithic): 10 to 20 inches Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained Parent material: Clayey residuum weathered from Parent material: Residuum weathered from shale and siltstone sandstone Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 2.7 inches Available water capacity: Mainly 1.6 inches

Additional Components Cabba and similar soils Composition: 20 percent Work and similar soils: 3 percent Geomorphic description: Knoll and plain Cabba and similar soils: 2 percent Slope: 2 to 15 percent Castner and similar soils: 2 percent Elevation: 4,200 to 6,000 feet Sagedale and similar soils: 2 percent Effective annual precipitation: 15 to 19 inches Amherst and similar soils: 1 percent Frost-free period: 85 to 115 days Surface layer texture: Loam Management Depth to bedrock (paralithic): 10 to 20 inches For management information about this map unit, Drainage class: Well drained see appropriate sections in Part II of this publication. Parent material: Loamy residuum weathered from sandstone and siltstone Native plant cover type: Rangeland 262D—Wayden-Castner-Cabba complex, Available water capacity: Mainly 2.5 inches 2 to 15 percent slopes Additional Components Sagedale and similar soils: 3 percent Setting Doney and similar soils: 2 percent Rock outcrop: 2 percent Field investigation intensity: Order 2 Vershal and similar soils: 2 percent Elevation: 4,200 to 6,000 feet Ticell and similar soils: 1 percent Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Management Major Component Description For management information about this map unit, see appropriate sections in Part II of this publication. Wayden and similar soils Composition: 40 percent Geomorphic description: Knoll and plain 265C—Sagedale clay loam, 2 to 8 percent Slope: 2 to 15 percent slopes Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Setting Frost-free period: 85 to 115 days Surface layer texture: Clay Elevation: 4,200 to 6,000 feet Depth to bedrock (paralithic): 10 to 20 inches Mean annual precipitation: 15 to 19 inches Drainage class: Well drained Frost-free period: 85 to 115 days 238 Soil Survey

Major Component Description Management Sagedale and similar soils For management information about this map unit, Composition: 85 percent see appropriate sections in Part II of this publication. Geomorphic description: Fan Slope: 2 to 8 percent Elevation: 4,200 to 6,000 feet 266B—Sweetgrass clay, 0 to 4 percent Effective annual precipitation: 15 to 19 inches slopes Frost-free period: 85 to 115 days Surface layer texture: Clay loam Setting Drainage class: Well drained Elevation: 4,200 to 6,000 feet Parent material: Clayey alluvium weathered from Mean annual precipitation: 15 to 19 inches shale and siltstone Frost-free period: 85 to 115 days Native plant cover type: Rangeland Available water capacity: Mainly 9.6 inches Major Component Description Additional Components Sweetgrass and similar soils Composition: 85 percent Macar and similar soils: 7 percent Geomorphic description: Tread on terrace Work and similar soils: 6 percent Slope: 0 to 4 percent Marcott and similar soils: 2 percent Elevation: 4,200 to 6,000 feet Management Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days For management information about this map unit, Surface layer texture: Clay see appropriate sections in Part II of this publication. Drainage class: Well drained Parent material: Clayey over sandy and gravelly alluvium 265D—Sagedale clay loam, Native plant cover type: Rangeland 8 to 15 percent slopes Available water capacity: Mainly 5.6 inches Additional Components Setting Roy and similar soils: 4 percent Elevation: 4,200 to 6,000 feet Shawmut and similar soils: 4 percent Mean annual precipitation: 15 to 19 inches Work and similar soils: 4 percent Frost-free period: 85 to 115 days Danvers and similar soils: 3 percent Major Component Description Management Sagedale and similar soils For management information about this map unit, Composition: 85 percent see appropriate sections in Part II of this publication. Geomorphic description: Fan Slope: 8 to 15 percent Elevation: 4,200 to 6,000 feet 267B—Beaverton gravelly sandy clay Effective annual precipitation: 15 to 19 inches loam, 0 to 4 percent slopes Frost-free period: 85 to 115 days Surface layer texture: Clay loam Setting Drainage class: Well drained Parent material: Clayey alluvium weathered from Elevation: 4,200 to 6,000 feet shale and siltstone Mean annual precipitation: 15 to 19 inches Native plant cover type: Rangeland Frost-free period: 85 to 115 days Available water capacity: Mainly 9.6 inches Major Component Description Additional Components Beaverton and similar soils Work and similar soils: 8 percent Composition: 85 percent Macar and similar soils: 4 percent Geomorphic description: Tread on stream terrace Marcott and similar soils: 3 percent Slope: 0 to 4 percent Sweet Grass County Area, Montana—Part I 239

Elevation: 4,200 to 6,000 feet Additional Components Effective annual precipitation: 15 to 19 inches Linwell and similar soils: 5 percent Frost-free period: 85 to 115 days Surface layer texture: Gravelly sandy clay loam Management Drainage class: Well drained For management information about this map unit, Parent material: Gravelly alluvium see appropriate sections in Part II of this publication. Native plant cover type: Rangeland Available water capacity: Mainly 3.5 inches Additional Components 269C—Danvers loam, 2 to 8 percent slopes Beaverton and similar soils: 5 percent Meadowcreek and similar soils: 5 percent Setting Roy and similar soils: 3 percent Turner and similar soils: 2 percent Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Management Frost-free period: 85 to 115 days For management information about this map unit, Major Component Description see appropriate sections in Part II of this publication. Danvers and similar soils Composition: 85 percent 268B—Overfelt-Roy complex, Geomorphic description: Tread on terrace 0 to 4 percent slopes Slope: 2 to 8 percent Elevation: 4,200 to 6,000 feet Setting Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Elevation: 4,200 to 6,000 feet Surface layer texture: Loam Mean annual precipitation: 15 to 19 inches Drainage class: Well drained Frost-free period: 85 to 115 days Parent material: Loamy alluvium Major Component Description Native plant cover type: Rangeland Available water capacity: Mainly 6.8 inches Overfelt and similar soils Composition: 50 percent Additional Components Geomorphic description: Tread on terrace Tamaneen and similar soils: 7 percent Slope: 0 to 4 percent Absarokee and similar soils: 4 percent Elevation: 4,200 to 6,000 feet Martinsdale and similar soils: 4 percent Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Management Surface layer texture: Clay loam For management information about this map unit, Drainage class: Well drained see appropriate sections in Part II of this publication. Parent material: Clayey over gravelly alluvium Native plant cover type: Rangeland Available water capacity: Mainly 6.2 inches 270C—Bacbuster-Castner complex, 2 to 8 percent slopes Roy and similar soils Composition: 45 percent Setting Geomorphic description: Tread on terrace Slope: 0 to 4 percent Field investigation intensity: Order 2 Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Surface layer texture: Gravelly clay loam Major Component Description Drainage class: Well drained Parent material: Gravelly alluvium Bacbuster and similar soils Native plant cover type: Rangeland Composition: 60 percent Available water capacity: Mainly 4.5 inches Geomorphic description: Plain and swale 240 Soil Survey

Slope: 4 to 8 percent Surface layer texture: Clay loam Elevation: 4,200 to 6,000 feet Depth to bedrock (paralithic): 20 to 40 inches Effective annual precipitation: 15 to 19 inches Drainage class: Well drained Frost-free period: 85 to 115 days Parent material: Clayey residuum weathered from Surface layer texture: Clay loam sandstone and shale Depth to bedrock (paralithic): 20 to 40 inches Native plant cover type: Rangeland Drainage class: Well drained Available water capacity: Mainly 5.0 inches Parent material: Clayey residuum weathered from sandstone and shale Castner and similar soils Native plant cover type: Rangeland Composition: 30 percent Available water capacity: Mainly 5.0 inches Geomorphic description: Knoll and plain Slope: 8 to 15 percent Castner and similar soils Elevation: 4,200 to 6,000 feet Composition: 30 percent Effective annual precipitation: 15 to 19 inches Geomorphic description: Knoll and plain Frost-free period: 85 to 115 days Slope: 2 to 8 percent Surface layer texture: Channery loam Elevation: 4,200 to 6,000 feet Depth to bedrock (lithic): 10 to 20 inches Effective annual precipitation: 15 to 19 inches Drainage class: Well drained Frost-free period: 85 to 115 days Parent material: Residuum weathered from Surface layer texture: Channery loam sandstone Depth to bedrock (lithic): 10 to 20 inches Native plant cover type: Rangeland Drainage class: Well drained Available water capacity: Mainly 1.6 inches Parent material: Residuum weathered from Additional Components sandstone Native plant cover type: Rangeland Bigsag and similar soils: 4 percent Available water capacity: Mainly 1.6 inches Korchea and similar soils: 3 percent Linwell and similar soils: 3 percent Additional Components Management Cabba and similar soils: 4 percent Linwell and similar soils: 3 percent For management information about this map unit, Vershal and similar soils: 3 percent see appropriate sections in Part II of this publication. Management For management information about this map unit, 271B—Sweetgrass gravelly loam, see appropriate sections in Part II of this publication. 0 to 4 percent slopes

270D—Bacbuster-Castner complex, Setting 8 to 15 percent slopes Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Setting Frost-free period: 85 to 115 days Field investigation intensity: Order 2 Major Component Description Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Sweetgrass and similar soils Frost-free period: 85 to 115 days Composition: 85 percent Geomorphic description: Tread on terrace Major Component Description Slope: 0 to 4 percent Bacbuster and similar soils Elevation: 4,200 to 6,000 feet Composition: 60 percent Effective annual precipitation: 15 to 19 inches Geomorphic description: Plain and swale Frost-free period: 85 to 115 days Slope: 8 to 15 percent Surface layer texture: Gravelly loam Elevation: 4,200 to 6,000 feet Drainage class: Well drained Effective annual precipitation: 15 to 19 inches Parent material: Clayey over sandy and gravelly Frost-free period: 85 to 115 days alluvium Sweet Grass County Area, Montana—Part I 241

Native plant cover type: Rangeland Major Component Description Available water capacity: Mainly 5.4 inches Work and similar soils Additional Components Composition: 85 percent Geomorphic description: Fan Tamaneen and similar soils: 5 percent Slope: 4 to 8 percent Turner and similar soils: 5 percent Elevation: 4,200 to 6,000 feet Wayden and similar soils: 5 percent Effective annual precipitation: 15 to 19 inches Management Frost-free period: 85 to 115 days Surface layer texture: Clay loam For management information about this map unit, Drainage class: Well drained see appropriate sections in Part II of this publication. Parent material: Clayey alluvium Native plant cover type: Rangeland 274B—Work clay loam, 0 to 4 percent Available water capacity: Mainly 8.6 inches slopes Additional Components Roy and similar soils: 4 percent Setting Danvers and similar soils: 3 percent Elevation: 4,200 to 6,000 feet Sagedale and similar soils: 3 percent Mean annual precipitation: 15 to 19 inches Shambo and similar soils: 3 percent Frost-free period: 85 to 115 days Marcott and similar soils: 2 percent Major Component Description Management Work and similar soils For management information about this map unit, Composition: 85 percent see appropriate sections in Part II of this publication. Geomorphic description: Tread on terrace Slope: 0 to 4 percent Elevation: 4,200 to 6,000 feet 274D—Work clay loam, 8 to 15 percent Effective annual precipitation: 15 to 19 inches slopes Frost-free period: 85 to 115 days Surface layer texture: Clay loam Setting Drainage class: Well drained Field investigation intensity: Order 2 Parent material: Clayey alluvium Elevation: 4,200 to 6,000 feet Native plant cover type: Rangeland Mean annual precipitation: 15 to 19 inches Available water capacity: Mainly 8.6 inches Frost-free period: 85 to 115 days Additional Components Major Component Description Roy and similar soils: 7 percent Work and similar soils Danvers and similar soils: 3 percent Composition: 85 percent Sagedale and similar soils: 3 percent Geomorphic description: Fan Shambo and similar soils: 2 percent Slope: 8 to 15 percent Management Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches For management information about this map unit, Frost-free period: 85 to 115 days see appropriate sections in Part II of this publication. Surface layer texture: Clay loam Drainage class: Well drained 274C—Work clay loam, 4 to 8 percent Parent material: Clayey alluvium slopes Native plant cover type: Rangeland Available water capacity: Mainly 8.6 inches Setting Additional Components Elevation: 4,200 to 6,000 feet Shambo and similar soils: 4 percent Mean annual precipitation: 15 to 19 inches Fairfield and similar soils: 3 percent Frost-free period: 85 to 115 days Linwell and similar soils: 3 percent 242 Soil Survey

Shawmut and similar soils: 3 percent Slope: 0 to 4 percent Macar and similar soils: 2 percent Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Management Frost-free period: 85 to 115 days For management information about this map unit, Surface layer texture: Clay loam see appropriate sections in Part II of this publication. Drainage class: Well drained Parent material: Clayey over gravelly alluvium Native plant cover type: Rangeland 274E—Work clay loam, 15 to 35 percent Available water capacity: Mainly 6.2 inches slopes Additional Components Setting Roy and similar soils: 5 percent Tamaneen and similar soils: 4 percent Elevation: 4,200 to 6,000 feet Marcott and similar soils: 3 percent Mean annual precipitation: 15 to 19 inches Work and similar soils: 3 percent Frost-free period: 85 to 115 days Management Major Component Description For management information about this map unit, Work and similar soils see appropriate sections in Part II of this publication. Composition: 85 percent Geomorphic description: Fan Slope: 15 to 35 percent 276A—Larry clay loam, 0 to 2 percent Elevation: 4,200 to 6,000 feet slopes Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Setting Surface layer texture: Clay loam Drainage class: Well drained Elevation: 3,750 to 6,000 feet Parent material: Clayey alluvium Mean annual precipitation: 10 to 19 inches Native plant cover type: Rangeland Frost-free period: 85 to 125 days Available water capacity: Mainly 8.6 inches Major Component Description Additional Components Larry and similar soils Linwell and similar soils: 7 percent Composition: 85 percent Farnuf and similar soils: 5 percent Geomorphic description: Flood plain Shambo and similar soils: 3 percent Slope: 0 to 2 percent Elevation: 3,750 to 6,000 feet Management Effective annual precipitation: 10 to 19 inches For management information about this map unit, Frost-free period: 85 to 125 days see appropriate sections in Part II of this publication. Surface layer texture: Clay loam Drainage class: Poorly drained Parent material: Loamy alluvium 275B—Overfelt clay loam, 0 to 4 percent Native plant cover type: Rangeland slopes Flooding: Rare Water table: Present Available water capacity: Mainly 10.3 inches Setting Additional Components Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Marcott and similar soils: 5 percent Frost-free period: 85 to 115 days Soapcreek and similar soils: 5 percent Swampcreek and similar soils: 5 percent Major Component Description Management Overfelt and similar soils Composition: 85 percent For management information about this map unit, Geomorphic description: Tread on stream terrace see appropriate sections in Part II of this publication. Sweet Grass County Area, Montana—Part I 243

277B—Marcott-Larry complex, 278B—Perma gravelly loam, 0 to 4 percent slopes 0 to 4 percent slopes

Setting Setting Elevation: 3,750 to 4,300 feet Elevation: 4,200 to 6,000 feet Mean annual precipitation: 10 to 14 inches Mean annual precipitation: 15 to 19 inches Frost-free period: 95 to 130 days Frost-free period: 85 to 115 days Major Component Description Major Component Description Marcott and similar soils Perma and similar soils Composition: 50 percent Composition: 85 percent Geomorphic description: Flood plain Geomorphic description: Tread on stream terrace Slope: 0 to 4 percent Slope: 0 to 4 percent Elevation: 3,750 to 4,300 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 10 to 14 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 95 to 130 days Frost-free period: 85 to 115 days Surface layer texture: Cobbly clay loam Surface layer texture: Gravelly loam Drainage class: Somewhat poorly drained Drainage class: Somewhat excessively drained Parent material: Clayey alluvium Parent material: Gravelly alluvium Native plant cover type: Rangeland Native plant cover type: Rangeland Flooding: Rare Available water capacity: Mainly 4.6 inches Water table: Present Salt affected: Saline within 30 inches Additional Components Sodium affected: Sodic within 30 inches Meadowcreek and similar soils: 5 percent Available water capacity: Mainly 6.7 inches Nesda and similar soils: 5 percent Roy and similar soils: 5 percent Larry and similar soils Composition: 40 percent Management Geomorphic description: Flood plain For management information about this map unit, Slope: 0 to 4 percent see appropriate sections in Part II of this publication. Elevation: 3,750 to 4,300 feet Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 130 days 278C—Perma gravelly loam, Surface layer texture: Clay loam 4 to 8 percent slopes Drainage class: Poorly drained Parent material: Loamy alluvium Setting Native plant cover type: Rangeland Flooding: Rare Elevation: 4,200 to 6,000 feet Water table: Present Mean annual precipitation: 15 to 19 inches Available water capacity: Mainly 10.3 inches Frost-free period: 85 to 115 days Additional Components Major Component Description Beaverell and similar soils: 4 percent Perma and similar soils Fairway and similar soils: 3 percent Composition: 85 percent Swampcreek and similar soils: 3 percent Geomorphic description: Tread on stream terrace Slope: 4 to 8 percent Management Elevation: 4,200 to 6,000 feet For management information about this map unit, Effective annual precipitation: 15 to 19 inches see appropriate sections in Part II of this publication. Frost-free period: 85 to 115 days 244 Soil Survey

Surface layer texture: Gravelly loam 281F—Shawmut-Castner complex, Drainage class: Somewhat excessively drained 15 to 60 percent slopes Parent material: Gravelly alluvium Native plant cover type: Rangeland Setting Available water capacity: Mainly 4.6 inches Elevation: 4,200 to 6,000 feet Additional Components Mean annual precipitation: 15 to 19 inches Shawmut and similar soils: 5 percent Frost-free period: 85 to 115 days Roy and similar soils: 4 percent Major Component Description Breeton and similar soils: 3 percent Shambo and similar soils: 3 percent Shawmut and similar soils Composition: 60 percent Management Geomorphic description: Side slope backslope on For management information about this map unit, escarpment see appropriate sections in Part II of this publication. Slope: 15 to 60 percent Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches 279C—Shambo clay loam, calcareous, Frost-free period: 85 to 115 days 4 to 8 percent slopes Surface layer texture: Gravelly loam Drainage class: Well drained Parent material: Gravelly glaciofluvial deposits Setting Native plant cover type: Rangeland Available water capacity: Mainly 4.3 inches Elevation: 4,200 to 6,000 feet Note: This soil exists on the upper one third of the Mean annual precipitation: 15 to 19 inches landform. Frost-free period: 85 to 115 days Castner and similar soils Major Component Description Composition: 30 percent Geomorphic description: Shambo and similar soils • Nose slope summit on escarpment Composition: 85 percent • Nose slope shoulder on escarpment Geomorphic description: Fan Slope: 15 to 60 percent Slope: 4 to 8 percent Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Surface layer texture: Channery loam Surface layer texture: Loam Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained Parent material: Loamy alluvium Parent material: Residuum weathered from Native plant cover type: Rangeland sandstone Available water capacity: Mainly 10.7 inches Native plant cover type: Rangeland Available water capacity: Mainly 1.4 inches Additional Components Additional Components Linwell and similar soils: 8 percent Sagedale and similar soils: 7 percent Winifred and similar soils: 3 percent Amor and similar soils: 2 percent Management Rock outcrop: 2 percent For management information about this map unit, Wayden and similar soils: 2 percent see appropriate sections in Part II of this publication. Sagedale and similar soils: 1 percent Sweet Grass County Area, Montana—Part I 245

Management Slope: 15 to 60 percent Elevation: 4,200 to 6,000 feet For management information about this map unit, Effective annual precipitation: 15 to 19 inches see appropriate sections in Part II of this publication. Frost-free period: 85 to 115 days Surface layer texture: Channery loam 282B—Bowery clay loam, 0 to 4 percent Depth to bedrock (lithic): 10 to 20 inches slopes Drainage class: Well drained Parent material: Residuum weathered from sandstone Setting Native plant cover type: Rangeland Field investigation intensity: Order 2 Available water capacity: Mainly 1.4 inches Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Wayden and similar soils Frost-free period: 85 to 115 days Composition: 40 percent Geomorphic description: Major Component Description • Side slope shoulder on escarpment Bowery and similar soils • Nose slope summit on escarpment Composition: 85 percent • Nose slope shoulder on escarpment Geomorphic description: Tread on stream terrace Slope: 15 to 60 percent Slope: 0 to 4 percent Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Surface layer texture: Clay Surface layer texture: Clay loam Depth to bedrock (paralithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained Parent material: Loamy alluvium Parent material: Clayey residuum weathered from Native plant cover type: Rangeland shale and siltstone Available water capacity: Mainly 9.4 inches Native plant cover type: Rangeland Available water capacity: Mainly 2.7 inches Additional Components Additional Components Laceycreek and similar soils: 5 percent Shambo and similar soils: 4 percent Cabba and similar soils: 2 percent Farnuf and similar soils: 3 percent Mowbray and similar soils: 2 percent Korchea and similar soils: 3 percent Rock outcrop: 2 percent Vershal and similar soils: 2 percent Management Work and similar soils: 2 percent For management information about this map unit, Management see appropriate sections in Part II of this publication. For management information about this map unit, see appropriate sections in Part II of this publication. 283F—Castner-Wayden complex, moist, 15 to 60 percent slopes 284C—Shawmut gravelly loam, Setting 2 to 8 percent slopes Elevation: 4,200 to 6,000 feet Setting Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Major Component Description Frost-free period: 85 to 115 days Castner and similar soils Major Component Description Composition: 50 percent Geomorphic description: Shawmut and similar soils • Nose slope summit on escarpment Composition: 93 percent • Nose slope shoulder on escarpment Geomorphic description: Tread on terrace 246 Soil Survey

Slope: 2 to 8 percent 286F—Wayden-Rock outcrop complex, Elevation: 4,200 to 6,000 feet 15 to 60 percent slopes Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Setting Surface layer texture: Gravelly loam Drainage class: Well drained Elevation: 4,200 to 6,000 feet Parent material: Gravelly glaciofluvial deposits Mean annual precipitation: 15 to 19 inches Native plant cover type: Rangeland Frost-free period: 85 to 115 days Available water capacity: Mainly 4.3 inches Major Component Description Additional Components Wayden and similar soils Tamaneen and similar soils: 7 percent Composition: 70 percent Geomorphic description: Management • Side slope shoulder on escarpment For management information about this map unit, • Nose slope summit on escarpment see appropriate sections in Part II of this publication. • Nose slope shoulder on escarpment Slope: 15 to 60 percent Elevation: 4,200 to 6,000 feet 284D—Shawmut gravelly loam, Effective annual precipitation: 15 to 19 inches 8 to 15 percent slopes Frost-free period: 85 to 115 days Surface layer texture: Clay Depth to bedrock (paralithic): 10 to 20 inches Setting Drainage class: Well drained Parent material: Clayey residuum weathered from Elevation: 4,200 to 6,000 feet shale and siltstone Mean annual precipitation: 15 to 19 inches Native plant cover type: Rangeland Frost-free period: 85 to 115 days Available water capacity: Mainly 2.7 inches Major Component Description Rock outcrop Composition: 20 percent Shawmut and similar soils Definition: Rock outcrop consists mainly of areas of Composition: 88 percent exposed hard bedrock. Geomorphic description: Fan Geomorphic description: Escarpment Slope: 8 to 15 percent Elevation: 4,200 to 6,000 feet Additional Components Effective annual precipitation: 15 to 19 inches Farnuf and similar soils: 6 percent Frost-free period: 85 to 115 days Albicalis and similar soils: 4 percent Surface layer texture: Gravelly loam Drainage class: Well drained Management Parent material: Gravelly glaciofluvial deposits For management information about this map unit, Native plant cover type: Rangeland see appropriate sections in Part II of this publication. Available water capacity: Mainly 4.3 inches Additional Components 288B—Turner sandy clay loam, Tamaneen and similar soils: 5 percent 0 to 4 percent slopes Roy and similar soils: 4 percent Work and similar soils: 3 percent Setting Management Elevation: 4,200 to 6,000 feet For management information about this map unit, Mean annual precipitation: 15 to 19 inches see appropriate sections in Part II of this publication. Frost-free period: 85 to 115 days Sweet Grass County Area, Montana—Part I 247

Major Component Description Management Turner and similar soils For management information about this map unit, Composition: 85 percent see appropriate sections in Part II of this publication. Geomorphic description: Tread on stream terrace Slope: 0 to 4 percent Elevation: 4,200 to 6,000 feet 290C—Breeton loam, 2 to 8 percent Effective annual precipitation: 15 to 19 inches slopes Frost-free period: 85 to 115 days Surface layer texture: Sandy clay loam Setting Drainage class: Well drained Elevation: 4,200 to 6,000 feet Parent material: Loamy over sandy and gravelly Mean annual precipitation: 15 to 19 inches alluvium Frost-free period: 85 to 115 days Native plant cover type: Rangeland Available water capacity: Mainly 5.0 inches Major Component Description Additional Components Breeton and similar soils Composition: 85 percent Roy and similar soils: 9 percent Geomorphic description: Fan Meadowcreek and similar soils: 3 percent Slope: 2 to 8 percent Shawmut and similar soils: 3 percent Elevation: 4,200 to 6,000 feet Management Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days For management information about this map unit, Surface layer texture: Loam see appropriate sections in Part II of this publication. Drainage class: Well drained Parent material: Coarse-loamy alluvium Native plant cover type: Rangeland 289A—Swampcreek gravelly sandy clay Available water capacity: Mainly 7.9 inches loam, 0 to 2 percent slopes Additional Components Setting Turner and similar soils: 6 percent Korchea and similar soils: 5 percent Elevation: 4,200 to 6,000 feet Fairway and similar soils: 4 percent Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Management Major Component Description For management information about this map unit, see appropriate sections in Part II of this publication. Swampcreek and similar soils Composition: 85 percent Geomorphic description: Tread on stream terrace 291B—Beaverton very cobbly loam, Slope: 0 to 2 percent 0 to 4 percent slopes Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Setting Frost-free period: 85 to 115 days Surface layer texture: Gravelly sandy clay loam Elevation: 4,200 to 6,000 feet Drainage class: Poorly drained Mean annual precipitation: 15 to 19 inches Parent material: Loamy over gravelly alluvium Frost-free period: 85 to 115 days Native plant cover type: Rangeland Major Component Description Flooding: Rare Water table: Present Beaverton and similar soils Available water capacity: Mainly 4.6 inches Composition: 85 percent Geomorphic description: Tread on stream terrace Additional Components Slope: 0 to 4 percent Beaverton and similar soils: 5 percent Elevation: 4,200 to 6,000 feet Lallie and similar soils: 5 percent Effective annual precipitation: 15 to 19 inches Meadowcreek and similar soils: 5 percent Frost-free period: 85 to 115 days 248 Soil Survey

Surface layer texture: Very cobbly loam 295B—Roy-Turner complex, 0 to 4 percent Drainage class: Well drained slopes Parent material: Gravelly alluvium Native plant cover type: Rangeland Setting Available water capacity: Mainly 3.3 inches Elevation: 4,200 to 6,000 feet Additional Components Mean annual precipitation: 15 to 19 inches Roy and similar soils: 10 percent Frost-free period: 85 to 115 days Turner and similar soils: 5 percent Major Component Description Management Roy and similar soils For management information about this map unit, Composition: 60 percent see appropriate sections in Part II of this publication. Geomorphic description: Tread on stream terrace Slope: 0 to 4 percent Elevation: 4,200 to 6,000 feet 294B—Roy gravelly loam, 0 to 4 percent Effective annual precipitation: 15 to 19 inches slopes Frost-free period: 85 to 115 days Surface layer texture: Gravelly clay loam Drainage class: Well drained Setting Parent material: Gravelly alluvium Elevation: 4,200 to 6,000 feet Native plant cover type: Rangeland Mean annual precipitation: 15 to 19 inches Available water capacity: Mainly 4.5 inches Frost-free period: 85 to 115 days Turner and similar soils Major Component Description Composition: 30 percent Roy and similar soils Geomorphic description: Tread on stream terrace Composition: 91 percent Slope: 0 to 4 percent Geomorphic description: Tread on stream terrace Elevation: 4,200 to 6,000 feet Slope: 0 to 4 percent Effective annual precipitation: 15 to 19 inches Elevation: 4,200 to 6,000 feet Frost-free period: 85 to 115 days Effective annual precipitation: 15 to 19 inches Surface layer texture: Sandy clay loam Frost-free period: 85 to 115 days Drainage class: Well drained Surface layer texture: Gravelly loam Parent material: Loamy over sandy and gravelly Drainage class: Well drained alluvium Parent material: Gravelly alluvium Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 5.0 inches Available water capacity: Mainly 4.6 inches Additional Components Additional Components Beaverton and similar soils: 4 percent Turner and similar soils: 5 percent Beaverton and similar soils: 3 percent Turner, seeped and similar soils: 4 percent Turner, seeped and similar soils: 3 percent Management Management For management information about this map unit, For management information about this map unit, see appropriate sections in Part II of this publication. see appropriate sections in Part II of this publication. Sweet Grass County Area, Montana—Part I 249

296B—Blossberg cobbly loam, Major Component Description 0 to 4 percent slopes Winspect and similar soils Composition: 85 percent Setting Geomorphic description: Nose slope summit on moraine Elevation: 3,750 to 4,300 feet Slope: 4 to 15 percent Mean annual precipitation: 10 to 14 inches Elevation: 5,300 to 6,200 feet Frost-free period: 95 to 130 days Effective annual precipitation: 17 to 20 inches Note: This map unit is strongly influenced by water Frost-free period: 70 to 90 days seepage from irrigation ditches. It is mainly Surface layer texture: Cobbly loam located in an area near the confluence of the Drainage class: Well drained Yellowstone and Boulder Rivers. Parent material: Gravelly glaciofluvial deposits Major Component Description Native plant cover type: Rangeland Available water capacity: Mainly 6.1 inches Blossberg and similar soils Composition: 85 percent Additional Components Geomorphic description: Tread on stream terrace Slope: 0 to 4 percent Shawmut and similar soils: 6 percent Elevation: 3,750 to 4,300 feet Shambo and similar soils: 4 percent Effective annual precipitation: 10 to 14 inches Work and similar soils: 4 percent Frost-free period: 95 to 130 days Fairfield, stony and similar soils: 1 percent Surface layer texture: Cobbly loam Management Rock fragments on the soil surface: 0.01 to 0.10 percent cobbles For management information about this map unit, Drainage class: Poorly drained see appropriate sections in Part II of this publication. Parent material: Loamy over sandy and gravelly alluvium Native plant cover type: Rangeland 303E—Winspect very cobbly loam, Water table: Present 15 to 35 percent slopes Available water capacity: Mainly 5.1 inches Note: This soil becomes supersaturated in the fine- loamy A and Bt horizons before starting to drain Setting through the sandy-skeletal substratum. The soil is Elevation: 5,300 to 6,200 feet wet throughout the growing season. Mean annual precipitation: 17 to 20 inches Additional Components Frost-free period: 70 to 90 days Swampcreek and similar soils: 10 percent Major Component Description Radersburg and similar soils: 5 percent Management Winspect and similar soils Composition: 85 percent For management information about this map unit, Geomorphic description: Nose slope summit on see appropriate sections in Part II of this publication. moraine Slope: 15 to 35 percent 303D—Winspect cobbly loam, Elevation: 5,300 to 6,200 feet 4 to 15 percent slopes Effective annual precipitation: 17 to 20 inches Frost-free period: 70 to 90 days Surface layer texture: Very cobbly loam Setting Drainage class: Well drained Elevation: 4,200 to 6,200 feet Parent material: Gravelly glaciofluvial deposits Mean annual precipitation: 17 to 20 inches Native plant cover type: Rangeland Frost-free period: 70 to 90 days Available water capacity: Mainly 6.2 inches 250 Soil Survey

Additional Components Management Shambo and similar soils: 4 percent For management information about this map unit, Work and similar soils: 4 percent see appropriate sections in Part II of this publication. Shawmut and similar soils: 3 percent Fairfield, stony and similar soils: 2 percent Winspect, bouldery and similar soils: 2 percent 304D—Shawmut-Shambo complex, Management 8 to 15 percent slopes For management information about this map unit, see appropriate sections in Part II of this publication. Setting Elevation: 5,300 to 6,200 feet 304C—Shawmut-Shambo complex, Mean annual precipitation: 17 to 20 inches 2 to 8 percent slopes Frost-free period: 70 to 90 days Major Component Description Setting Elevation: 5,300 to 6,200 feet Shawmut and similar soils Mean annual precipitation: 17 to 20 inches Composition: 50 percent Frost-free period: 70 to 90 days Geomorphic description: Fan Slope: 8 to 15 percent Major Component Description Elevation: 5,300 to 6,200 feet Shawmut and similar soils Effective annual precipitation: 17 to 20 inches Composition: 53 percent Frost-free period: 70 to 90 days Geomorphic description: Fan Surface layer texture: Gravelly loam Slope: 2 to 8 percent Drainage class: Well drained Elevation: 5,300 to 6,200 feet Parent material: Gravelly glaciofluvial deposits Effective annual precipitation: 17 to 20 inches Native plant cover type: Rangeland Frost-free period: 70 to 90 days Available water capacity: Mainly 4.3 inches Surface layer texture: Gravelly loam Drainage class: Well drained Shambo and similar soils Parent material: Gravelly glaciofluvial deposits Composition: 40 percent Native plant cover type: Rangeland Geomorphic description: Fan Available water capacity: Mainly 4.3 inches Slope: 8 to 15 percent Elevation: 5,300 to 6,200 feet Shambo and similar soils Effective annual precipitation: 17 to 20 inches Composition: 40 percent Frost-free period: 70 to 90 days Geomorphic description: Fan Surface layer texture: Loam Slope: 2 to 8 percent Drainage class: Well drained Elevation: 5,300 to 6,200 feet Parent material: Loamy alluvium Effective annual precipitation: 17 to 20 inches Native plant cover type: Rangeland Frost-free period: 70 to 90 days Available water capacity: Mainly 10.7 inches Surface layer texture: Loam Drainage class: Well drained Additional Components Parent material: Loamy alluvium Native plant cover type: Rangeland Farnuf and similar soils: 4 percent Available water capacity: Mainly 10.7 inches Winspect and similar soils: 4 percent Tamaneen and similar soils: 2 percent Additional Components Management Tamaneen and similar soils: 3 percent Meadowcreek and similar soils: 2 percent For management information about this map unit, Winspect and similar soils: 2 percent see appropriate sections in Part II of this publication. Sweet Grass County Area, Montana—Part I 251

307E—Cabba-Doney loams, Management 8 to 35 percent slopes For management information about this map unit, see appropriate sections in Part II of this publication. Setting Field investigation intensity: Order 2 308C—Meagher gravelly loam, Elevation: 4,200 to 6,000 feet 2 to 8 percent slopes Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Setting Major Component Description Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Cabba and similar soils Frost-free period: 85 to 115 days Composition: 50 percent Major Component Description Geomorphic description: • Nose slope summit on hill Meagher and similar soils • Nose slope backslope on hill Composition: 85 percent • Side slope backslope on hill Geomorphic description: Tread on terrace Slope: 8 to 35 percent Slope: 2 to 8 percent Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Surface layer texture: Loam Surface layer texture: Gravelly loam Depth to bedrock (paralithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained Parent material: Loamy alluvium Parent material: Loamy residuum weathered from Native plant cover type: Rangeland sandstone and siltstone Available water capacity: Mainly 6.1 inches Native plant cover type: Rangeland Additional Components Available water capacity: Mainly 2.5 inches Farnuf and similar soils: 5 percent Doney and similar soils Martinsdale and similar soils: 5 percent Composition: 40 percent Shawmut and similar soils: 5 percent Geomorphic description: Management • Base slope backslope on hill • Base slope footslope on hill For management information about this map unit, • Side slope backslope on hill see appropriate sections in Part II of this publication. Slope: 8 to 35 percent Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches 309E—Ticell-Amor loams, 8 to 35 percent Frost-free period: 85 to 115 days slopes Surface layer texture: Loam Depth to bedrock (paralithic): 20 to 40 inches Setting Drainage class: Well drained Elevation: 4,200 to 6,000 feet Parent material: Loamy residuum weathered from Mean annual precipitation: 15 to 19 inches sandstone and siltstone Frost-free period: 85 to 115 days Native plant cover type: Rangeland Available water capacity: Mainly 4.6 inches Major Component Description Ticell and similar soils Additional Components Composition: 50 percent Castner and similar soils: 4 percent Geomorphic description: Rock outcrop: 3 percent • Nose slope summit on hill Wayden and similar soils: 3 percent • Nose slope shoulder on hill 252 Soil Survey

Slope: 8 to 35 percent Slope: 15 to 35 percent Elevation: 4,200 to 6,000 feet Elevation: 5,300 to 6,200 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 17 to 20 inches Frost-free period: 85 to 115 days Frost-free period: 70 to 90 days Surface layer texture: Loam Surface layer texture: Cobbly loam Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained Parent material: Gravelly glaciofluvial deposits Parent material: Residuum weathered from Native plant cover type: Rangeland calcareous sandstone Available water capacity: Mainly 6.5 inches Native plant cover type: Rangeland Available water capacity: Mainly 2.9 inches Ticell and similar soils Composition: 30 percent Amor and similar soils Geomorphic description: Composition: 40 percent • Nose slope summit on hill Geomorphic description: • Nose slope shoulder on hill • Base slope backslope on hill Slope: 15 to 35 percent • Base slope footslope on hill Elevation: 5,300 to 6,200 feet • Side slope backslope on hill Effective annual precipitation: 17 to 20 inches Slope: 8 to 35 percent Frost-free period: 70 to 90 days Elevation: 4,200 to 6,000 feet Surface layer texture: Loam Effective annual precipitation: 15 to 19 inches Depth to bedrock (lithic): 10 to 20 inches Frost-free period: 85 to 115 days Drainage class: Well drained Surface layer texture: Loam Parent material: Residuum weathered from Depth to bedrock (paralithic): 20 to 40 inches calcareous sandstone Drainage class: Well drained Native plant cover type: Rangeland Parent material: Loamy residuum weathered from Available water capacity: Mainly 2.9 inches sandstone and siltstone Additional Components Native plant cover type: Rangeland Available water capacity: Mainly 6.1 inches Amor and similar soils: 6 percent Ticell, stony and similar soils: 3 percent Additional Components Winspect, bouldery and similar soils: 1 percent Macar and similar soils: 5 percent Management Castner and similar soils: 3 percent Cabba and similar soils: 2 percent For management information about this map unit, see appropriate sections in Part II of this publication. Management For management information about this map unit, see appropriate sections in Part II of this publication. 311C—Roy, extremely stony-Turner complex, 2 to 8 percent slopes

310E—Winspect-Ticell complex, Setting 15 to 35 percent slopes Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Setting Frost-free period: 85 to 115 days Elevation: 5,300 to 6,200 feet Major Component Description Mean annual precipitation: 17 to 20 inches Frost-free period: 70 to 90 days Roy and similar soils Composition: 65 percent Major Component Description Geomorphic description: Tread on stream terrace Winspect and similar soils Slope: 0 to 4 percent Composition: 60 percent Elevation: 4,200 to 6,000 feet Geomorphic description: Effective annual precipitation: 15 to 19 inches • Base slope footslope on hill Frost-free period: 85 to 115 days • Base slope toeslope on hill Surface layer texture: Gravelly clay loam Sweet Grass County Area, Montana—Part I 253

Rock fragments on the soil surface: 3 to 15 percent Native plant cover type: Rangeland stones, 2 to 3 feet apart Available water capacity: Mainly 0.6 inches Drainage class: Well drained Additional Components Parent material: Gravelly alluvium Native plant cover type: Rangeland Cabba and similar soils: 3 percent Available water capacity: Mainly 4.5 inches Castner and similar soils: 3 percent Ticell and similar soils: 3 percent Turner and similar soils Amor and similar soils: 2 percent Composition: 30 percent Doney and similar soils: 2 percent Geomorphic description: Tread on stream terrace Rock outcrop: 2 percent Slope: 2 to 8 percent Management Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches For management information about this map unit, Frost-free period: 85 to 115 days see appropriate sections in Part II of this publication. Surface layer texture: Sandy clay loam Rock fragments on the soil surface: 3 to 15 percent stones, 2 to 3 feet apart 312F—Vershal very channery loam, Drainage class: Well drained 15 to 60 percent slopes Parent material: Loamy over sandy and gravelly alluvium Native plant cover type: Rangeland Setting Available water capacity: Mainly 4.9 inches Field investigation intensity: Order 2 Additional Components Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Turner, seeped and similar soils: 5 percent Frost-free period: 85 to 115 days Management Major Component Description For management information about this map unit, Vershal and similar soils see appropriate sections in Part II of this publication. Composition: 85 percent Geomorphic description: 312D—Vershal very channery loam, • Nose slope summit on escarpment 2 to 15 percent slopes • Nose slope shoulder on escarpment Slope: 15 to 60 percent Elevation: 4,200 to 6,000 feet Setting Effective annual precipitation: 15 to 19 inches Field investigation intensity: Order 2 Frost-free period: 85 to 115 days Elevation: 4,200 to 6,000 feet Surface layer texture: Very channery loam Mean annual precipitation: 15 to 19 inches Depth to bedrock (lithic): 4 to 10 inches Frost-free period: 85 to 115 days Drainage class: Well drained Parent material: Residuum weathered from Major Component Description sandstone Vershal and similar soils Native plant cover type: Rangeland Composition: 85 percent Available water capacity: Mainly 0.6 inches Geomorphic description: Knoll and plain Additional Components Slope: 2 to 15 percent Elevation: 4,200 to 6,000 feet Amor and similar soils: 4 percent Effective annual precipitation: 15 to 19 inches Castner and similar soils: 4 percent Frost-free period: 85 to 115 days Wayden and similar soils: 4 percent Surface layer texture: Very channery loam Rock outcrop: 3 percent Depth to bedrock (lithic): 4 to 10 inches Management Drainage class: Well drained Parent material: Residuum weathered from For management information about this map unit, sandstone see appropriate sections in Part II of this publication. 254 Soil Survey

313C—Roy-Tamaneen complex, Major Component Description 2 to 8 percent slopes Absarokee and similar soils Composition: 50 percent Setting Geomorphic description: Plain and swale Slope: 2 to 8 percent Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Major Component Description Surface layer texture: Loam Depth to bedrock (lithic): 20 to 40 inches Roy and similar soils Drainage class: Well drained Composition: 50 percent Parent material: Silty and clayey residuum weathered Geomorphic description: Tread on terrace from sandstone and shale Slope: 2 to 8 percent Native plant cover type: Rangeland Elevation: 4,200 to 6,000 feet Available water capacity: Mainly 4.1 inches Effective annual precipitation: 15 to 19 inches Amherst and similar soils Frost-free period: 85 to 115 days Composition: 40 percent Surface layer texture: Very gravelly loam Geomorphic description: Knoll and plain Drainage class: Well drained Slope: 2 to 8 percent Parent material: Gravelly glaciofluvial deposits Elevation: 4,200 to 6,000 feet Native plant cover type: Rangeland Effective annual precipitation: 15 to 19 inches Available water capacity: Mainly 4.5 inches Frost-free period: 85 to 115 days Surface layer texture: Gravelly clay loam Tamaneen and similar soils Depth to bedrock (lithic): 10 to 20 inches Composition: 40 percent Drainage class: Well drained Geomorphic description: Tread on terrace Parent material: Clayey residuum weathered from Slope: 2 to 8 percent sandstone Elevation: 4,200 to 6,000 feet Native plant cover type: Rangeland Effective annual precipitation: 15 to 19 inches Available water capacity: Mainly 2.5 inches Frost-free period: 85 to 115 days Surface layer texture: Cobbly loam Additional Components Drainage class: Well drained Castner and similar soils: 4 percent Parent material: Clayey over gravelly glaciofluvial Beenom and similar soils: 2 percent deposits Wayden and similar soils: 2 percent Native plant cover type: Rangeland Winifred and similar soils: 2 percent Available water capacity: Mainly 6.5 inches Management Additional Components For management information about this map unit, Farnuf and similar soils: 4 percent see appropriate sections in Part II of this publication. Shawmut and similar soils: 4 percent Beaverton and similar soils: 2 percent Management 330D—Absarokee-Amherst complex, For management information about this map unit, 8 to 15 percent slopes see appropriate sections in Part II of this publication. Setting 330C—Absarokee-Amherst complex, Elevation: 4,200 to 6,000 feet 2 to 8 percent slopes Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Setting Major Component Description Elevation: 4,200 to 6,000 feet Absarokee and similar soils Mean annual precipitation: 15 to 19 inches Composition: 51 percent Frost-free period: 85 to 115 days Geomorphic description: Plain and swale Sweet Grass County Area, Montana—Part I 255

Slope: 8 to 15 percent Slope: 15 to 60 percent Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Surface layer texture: Loam Surface layer texture: Clay Depth to bedrock (lithic): 20 to 40 inches Depth to bedrock (paralithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained Parent material: Silty and clayey residuum weathered Parent material: Clayey residuum weathered from from sandstone and shale shale and siltstone Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 4.1 inches Available water capacity: Mainly 2.7 inches

Amherst and similar soils Castner and similar soils Composition: 40 percent Composition: 40 percent Geomorphic description: Knoll and plain Geomorphic description: Slope: 8 to 15 percent • Nose slope summit on escarpment Elevation: 4,200 to 6,000 feet • Nose slope shoulder on escarpment Effective annual precipitation: 15 to 19 inches Slope: 15 to 60 percent Frost-free period: 85 to 115 days Elevation: 4,200 to 6,000 feet Surface layer texture: Gravelly clay loam Effective annual precipitation: 15 to 19 inches Depth to bedrock (lithic): 10 to 20 inches Frost-free period: 85 to 115 days Drainage class: Well drained Surface layer texture: Channery loam Parent material: Clayey residuum weathered from Depth to bedrock (lithic): 10 to 20 inches sandstone Drainage class: Well drained Native plant cover type: Rangeland Parent material: Residuum weathered from Available water capacity: Mainly 2.5 inches sandstone Native plant cover type: Rangeland Additional Components Available water capacity: Mainly 1.4 inches Castner and similar soils: 3 percent Additional Components Rock outcrop: 2 percent Wayden and similar soils: 2 percent Cabba and similar soils: 3 percent Winifred and similar soils: 2 percent Shambo and similar soils: 3 percent Farnuf and similar soils: 2 percent Management Rock outcrop: 2 percent For management information about this map unit, Management see appropriate sections in Part II of this publication. For management information about this map unit, see appropriate sections in Part II of this publication. 331F—Wayden-Castner complex, 15 to 60 percent slopes 332D—Ticell loam, 2 to 15 percent slopes Setting Setting Field investigation intensity: Order 2 Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Major Component Description Major Component Description Wayden and similar soils Ticell and similar soils Composition: 50 percent Composition: 85 percent Geomorphic description: Geomorphic description: Knoll and plain • Side slope shoulder on escarpment Slope: 2 to 15 percent • Nose slope summit on escarpment Elevation: 4,200 to 6,000 feet • Nose slope shoulder on escarpment Effective annual precipitation: 15 to 19 inches 256 Soil Survey

Frost-free period: 85 to 115 days Vershal and similar soils: 3 percent Surface layer texture: Loam Castner and similar soils: 2 percent Depth to bedrock (lithic): 10 to 20 inches Management Drainage class: Well drained Parent material: Residuum weathered from For management information about this map unit, calcareous sandstone see appropriate sections in Part II of this publication. Native plant cover type: Rangeland Available water capacity: Mainly 2.9 inches 333F—Shawmut-Castner-Rock outcrop Additional Components complex, 15 to 60 percent slopes Cabba and similar soils: 3 percent Castner and similar soils: 3 percent Setting Work and similar soils: 3 percent Elevation: 5,300 to 6,200 feet Amor and similar soils: 2 percent Mean annual precipitation: 17 to 20 inches Reedwest and similar soils: 2 percent Frost-free period: 70 to 90 days Rock outcrop: 2 percent Major Component Description Management Shawmut and similar soils For management information about this map unit, Composition: 40 percent see appropriate sections in Part II of this publication. Geomorphic description: Base slope backslope on escarpment Slope: 15 to 60 percent 332E—Ticell loam, 15 to 35 percent Elevation: 5,300 to 6,200 feet slopes Effective annual precipitation: 17 to 20 inches Frost-free period: 70 to 90 days Surface layer texture: Gravelly loam Setting Drainage class: Well drained Elevation: 4,200 to 6,000 feet Parent material: Gravelly alluvium Mean annual precipitation: 15 to 19 inches Native plant cover type: Forestland Frost-free period: 85 to 115 days Available water capacity: Mainly 4.3 inches Major Component Description Castner and similar soils Ticell and similar soils Composition: 33 percent Composition: 85 percent Geomorphic description: Geomorphic description: • Nose slope summit on escarpment • Nose slope summit on hill • Nose slope shoulder on escarpment • Nose slope shoulder on hill Slope: 15 to 60 percent Slope: 15 to 35 percent Elevation: 5,300 to 6,200 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 17 to 20 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 70 to 90 days Frost-free period: 85 to 115 days Surface layer texture: Stony loam Surface layer texture: Loam Depth to bedrock (lithic): 10 to 20 inches Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained Parent material: Residuum weathered from Parent material: Residuum weathered from sandstone calcareous sandstone Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 1.6 inches Available water capacity: Mainly 2.9 inches Rock outcrop Additional Components Composition: 20 percent Cabba and similar soils: 4 percent Definition: Rock outcrop consists mainly of areas of Amor and similar soils: 3 percent exposed hard bedrock. Doney and similar soils: 3 percent Geomorphic description: Escarpment Sweet Grass County Area, Montana—Part I 257

Additional Components Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Cabba and similar soils: 4 percent Surface layer texture: Gravelly clay loam Reedwest and similar soils: 3 percent Depth to bedrock (lithic): 10 to 20 inches Management Drainage class: Well drained Parent material: Clayey residuum weathered from For management information about this map unit, sandstone see appropriate sections in Part II of this publication. Native plant cover type: Rangeland Available water capacity: Mainly 2.5 inches 335D—Cabba-Castner-Amherst complex, Additional Components 2 to 15 percent slopes Absarokee and similar soils: 3 percent Reedwest and similar soils: 3 percent Setting Wayden and similar soils: 3 percent Rock outcrop: 1 percent Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Management Frost-free period: 85 to 115 days For management information about this map unit, Major Component Description see appropriate sections in Part II of this publication. Cabba and similar soils Composition: 40 percent 336E—Sinnigam-Wayden complex, moist, Geomorphic description: Knoll and plain 15 to 45 percent slopes Slope: 2 to 15 percent Elevation: 4,200 to 6,000 feet Setting Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Elevation: 4,200 to 6,000 feet Surface layer texture: Loam Mean annual precipitation: 15 to 19 inches Depth to bedrock (paralithic): 10 to 20 inches Frost-free period: 85 to 115 days Drainage class: Well drained Major Component Description Parent material: Loamy residuum weathered from sandstone and siltstone Sinnigam and similar soils Native plant cover type: Rangeland Composition: 50 percent Available water capacity: Mainly 2.5 inches Geomorphic description: • Nose slope summit on hill Castner and similar soils • Nose slope shoulder on hill Composition: 30 percent Slope: 15 to 45 percent Geomorphic description: Knoll and plain Elevation: 4,200 to 6,000 feet Slope: 2 to 15 percent Effective annual precipitation: 15 to 19 inches Elevation: 4,200 to 6,000 feet Frost-free period: 85 to 115 days Effective annual precipitation: 15 to 19 inches Surface layer texture: Very channery clay loam Frost-free period: 85 to 115 days Depth to bedrock (lithic): 10 to 20 inches Surface layer texture: Channery loam Drainage class: Well drained Depth to bedrock (lithic): 10 to 20 inches Parent material: Clayey residuum weathered from Drainage class: Well drained sandstone and shale Parent material: Residuum weathered from Native plant cover type: Rangeland sandstone Available water capacity: Mainly 2.0 inches Native plant cover type: Rangeland Available water capacity: Mainly 1.6 inches Wayden and similar soils Composition: 40 percent Amherst and similar soils Geomorphic description: Composition: 20 percent • Nose slope summit on hill Geomorphic description: Knoll and plain • Nose slope shoulder on hill Slope: 2 to 15 percent • Side slope shoulder on hill Elevation: 4,200 to 6,000 feet Slope: 15 to 45 percent 258 Soil Survey

Elevation: 4,200 to 6,000 feet 337D—Work gravelly clay loam, Effective annual precipitation: 15 to 19 inches 8 to 15 percent slopes Frost-free period: 85 to 115 days Surface layer texture: Clay Setting Depth to bedrock (paralithic): 10 to 20 inches Drainage class: Well drained Elevation: 4,200 to 6,000 feet Parent material: Clayey residuum weathered from Mean annual precipitation: 15 to 19 inches shale and siltstone Frost-free period: 85 to 115 days Native plant cover type: Rangeland Major Component Description Available water capacity: Mainly 2.7 inches Work and similar soils Additional Components Composition: 85 percent Absarokee and similar soils: 3 percent Geomorphic description: Fan Castner and similar soils: 3 percent Slope: 8 to 15 percent Amherst and similar soils: 2 percent Elevation: 4,200 to 6,000 feet Rock outcrop: 2 percent Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Management Surface layer texture: Gravelly clay loam For management information about this map unit, Drainage class: Well drained see appropriate sections in Part II of this publication. Parent material: Clayey alluvium Native plant cover type: Rangeland Available water capacity: Mainly 8.4 inches 337C—Work gravelly clay loam, 2 to 8 percent slopes Additional Components Shawmut and similar soils: 5 percent Setting Danvers and similar soils: 4 percent Roy and similar soils: 3 percent Elevation: 4,200 to 6,000 feet Tamaneen and similar soils: 3 percent Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Management Major Component Description For management information about this map unit, see appropriate sections in Part II of this publication. Work and similar soils Composition: 85 percent Geomorphic description: Fan Slope: 2 to 8 percent 342E—Ashbon-Winkler-Weedzunit Elevation: 4,200 to 6,000 feet complex, 15 to 35 percent slopes Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Setting Surface layer texture: Gravelly clay loam Drainage class: Well drained Elevation: 3,900 to 6,000 feet Parent material: Clayey alluvium Mean annual precipitation: 15 to 19 inches Native plant cover type: Rangeland Frost-free period: 85 to 115 days Available water capacity: Mainly 8.4 inches Major Component Description Additional Components Shawmut and similar soils: 5 percent Ashbon and similar soils Danvers and similar soils: 4 percent Composition: 40 percent Roy and similar soils: 3 percent Geomorphic description: Tamaneen and similar soils: 3 percent • Nose slope summit on hill • Nose slope shoulder on hill Management Slope: 15 to 25 percent For management information about this map unit, Elevation: 3,900 to 6,000 feet see appropriate sections in Part II of this publication. Effective annual precipitation: 15 to 19 inches Sweet Grass County Area, Montana—Part I 259

Frost-free period: 85 to 115 days 343F—Ashbon-Winkler-Rock outcrop Surface layer texture: Very gravelly sandy loam complex, 35 to 60 percent slopes Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Setting Parent material: Residuum weathered from tuff breccia Elevation: 3,900 to 6,000 feet Native plant cover type: Forestland Mean annual precipitation: 15 to 19 inches Available water capacity: Mainly 1.2 inches Frost-free period: 85 to 115 days Major Component Description Winkler and similar soils Composition: 30 percent Ashbon and similar soils Geomorphic description: Composition: 40 percent • Side slope backslope on hill Geomorphic description: • Base slope footslope on hill • Nose slope summit on hill • Base slope backslope on hill • Nose slope shoulder on hill Slope: 15 to 35 percent Slope: 35 to 60 percent Elevation: 3,900 to 6,000 feet Elevation: 3,900 to 6,000 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Surface layer texture: Very gravelly sandy loam Surface layer texture: Very gravelly sandy loam Drainage class: Somewhat excessively drained Depth to bedrock (lithic): 10 to 20 inches Parent material: Gravelly colluvium weathered from Drainage class: Well drained tuff breccia Parent material: Residuum weathered from tuff Native plant cover type: Forestland breccia Available water capacity: Mainly 3.6 inches Native plant cover type: Forestland Available water capacity: Mainly 1.2 inches Weedzunit and similar soils Composition: 20 percent Winkler and similar soils Geomorphic description: Composition: 30 percent • Base slope backslope on hill Geomorphic description: • Base slope footslope on hill • Side slope backslope on hill • Side slope backslope on hill • Base slope footslope on hill Slope: 15 to 35 percent • Base slope backslope on hill Elevation: 3,900 to 6,000 feet Slope: 35 to 60 percent Effective annual precipitation: 15 to 19 inches Elevation: 3,900 to 6,000 feet Frost-free period: 85 to 115 days Effective annual precipitation: 15 to 19 inches Surface layer texture: Fine sandy loam Frost-free period: 85 to 115 days Depth to bedrock (lithic): 20 to 40 inches Surface layer texture: Very gravelly sandy loam Drainage class: Well drained Drainage class: Somewhat excessively drained Parent material: Residuum weathered from tuff Parent material: Gravelly colluvium weathered from breccia tuff breccia Native plant cover type: Rangeland Native plant cover type: Forestland Available water capacity: Mainly 4.0 inches Available water capacity: Mainly 3.6 inches

Additional Components Rock outcrop Composition: 20 percent Work and similar soils: 4 percent Definition: Rock outcrop consists mainly of areas of Farnuf and similar soils: 3 percent exposed hard bedrock. Perma and similar soils: 3 percent Geomorphic description: Hill Management Additional Components For management information about this map unit, Perma and similar soils: 5 percent see appropriate sections in Part II of this publication. Weedzunit and similar soils: 5 percent 260 Soil Survey

Management Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days For management information about this map unit, Surface layer texture: Gravelly loam see appropriate sections in Part II of this publication. Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained 344F—Vision-Sweetweed-Whitlash Parent material: Residuum weathered from tuff complex, 25 to 60 percent slopes breccia Native plant cover type: Forestland Available water capacity: Mainly 2.0 inches Setting Additional Components Elevation: 3,900 to 6,000 feet Mean annual precipitation: 15 to 19 inches Rock outcrop: 5 percent Frost-free period: 85 to 115 days Winkler and similar soils: 3 percent Ashbon and similar soils: 2 percent Major Component Description Management Vision and similar soils Composition: 40 percent For management information about this map unit, Geomorphic description: see appropriate sections in Part II of this publication. • Base slope backslope on hill • Base slope footslope on hill Slope: 35 to 60 percent 345D—Weedzunit-Ashbon complex, Elevation: 3,900 to 6,000 feet 4 to 15 percent slopes Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Setting Surface layer texture: Gravelly loam Drainage class: Well drained Elevation: 4,200 to 6,000 feet Parent material: Gravelly colluvium weathered from Mean annual precipitation: 15 to 19 inches tuff breccia Frost-free period: 85 to 115 days Native plant cover type: Forestland Major Component Description Available water capacity: Mainly 5.8 inches Weedzunit and similar soils Sweetweed and similar soils Composition: 50 percent Composition: 30 percent Geomorphic description: Geomorphic description: • Side slope footslope on hill • Base slope footslope on hill • Side slope backslope on hill • Base slope toeslope on hill Slope: 8 to 15 percent Slope: 25 to 35 percent Elevation: 4,200 to 6,000 feet Elevation: 3,900 to 6,000 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Surface layer texture: Fine sandy loam Surface layer texture: Loam Depth to bedrock (lithic): 20 to 40 inches Drainage class: Well drained Drainage class: Well drained Parent material: Loamy alluvium or colluvium Parent material: Residuum weathered from tuff weathered from tuff breccia breccia Native plant cover type: Forestland Native plant cover type: Rangeland Available water capacity: Mainly 9.1 inches Available water capacity: Mainly 4.0 inches

Whitlash and similar soils Ashbon and similar soils Composition: 20 percent Composition: 40 percent Geomorphic description: Geomorphic description: • Nose slope summit on hill • Nose slope summit on hill • Nose slope shoulder on hill • Nose slope shoulder on hill Slope: 35 to 60 percent Slope: 8 to 15 percent Elevation: 3,900 to 6,000 feet Elevation: 4,200 to 6,000 feet Sweet Grass County Area, Montana—Part I 261

Effective annual precipitation: 15 to 19 inches Elevation: 4,200 to 6,000 feet Frost-free period: 85 to 115 days Effective annual precipitation: 15 to 19 inches Surface layer texture: Very gravelly sandy loam Frost-free period: 85 to 115 days Depth to bedrock (lithic): 10 to 20 inches Surface layer texture: Very gravelly sandy loam Drainage class: Well drained Depth to bedrock (lithic): 10 to 20 inches Parent material: Residuum weathered from tuff Drainage class: Well drained breccia Parent material: Residuum weathered from tuff Native plant cover type: Rangeland breccia Available water capacity: Mainly 1.3 inches Native plant cover type: Rangeland Available water capacity: Mainly 1.2 inches Additional Components Additional Components Shambo and similar soils: 4 percent Farnuf and similar soils: 3 percent Breeton and similar soils: 4 percent Pianohill and similar soils: 3 percent Shambo and similar soils: 4 percent Pianohill and similar soils: 2 percent Management Management For management information about this map unit, see appropriate sections in Part II of this publication. For management information about this map unit, see appropriate sections in Part II of this publication. 345E—Weedzunit-Ashbon complex, 15 to 45 percent slopes 346E—Farnuf-Reedwest-Shawmut complex, 15 to 35 percent slopes Setting Setting Field investigation intensity: Order 2 Elevation: 4,200 to 6,000 feet Elevation: 5,300 to 6,200 feet Mean annual precipitation: 15 to 19 inches Mean annual precipitation: 17 to 20 inches Frost-free period: 85 to 115 days Frost-free period: 70 to 90 days Major Component Description Major Component Description Weedzunit and similar soils Farnuf and similar soils Composition: 50 percent Composition: 43 percent Geomorphic description: Geomorphic description: Base slope toeslope on hill • Base slope backslope on hill Slope: 15 to 25 percent • Base slope footslope on hill Elevation: 5,300 to 6,200 feet • Side slope backslope on hill Effective annual precipitation: 17 to 20 inches Slope: 15 to 35 percent Frost-free period: 70 to 90 days Elevation: 4,200 to 6,000 feet Surface layer texture: Stony loam Effective annual precipitation: 15 to 19 inches Drainage class: Well drained Frost-free period: 85 to 115 days Parent material: Loamy alluvium Surface layer texture: Fine sandy loam Native plant cover type: Rangeland Depth to bedrock (lithic): 20 to 40 inches Available water capacity: Mainly 9.1 inches Drainage class: Well drained Parent material: Residuum weathered from tuff Reedwest and similar soils breccia Composition: 33 percent Native plant cover type: Rangeland Geomorphic description: Available water capacity: Mainly 4.0 inches • Side slope backslope on hill • Base slope backslope on hill Ashbon and similar soils • Base slope footslope on hill Composition: 40 percent Slope: 15 to 35 percent Geomorphic description: Elevation: 5,300 to 6,200 feet • Nose slope summit on hill Effective annual precipitation: 17 to 20 inches • Nose slope shoulder on hill Frost-free period: 70 to 90 days Slope: 15 to 45 percent Surface layer texture: Loam 262 Soil Survey

Depth to bedrock (paralithic): 20 to 40 inches Native plant cover type: Rangeland Drainage class: Well drained Available water capacity: Mainly 1.4 inches Parent material: Loamy residuum weathered from sandstone and siltstone Lymanson and similar soils Native plant cover type: Rangeland Composition: 30 percent Available water capacity: Mainly 4.6 inches Geomorphic description: Mountainflank backslope on mountain Shawmut and similar soils Slope: 2 to 15 percent Composition: 20 percent Elevation: 6,000 to 7,500 feet Geomorphic description: Side slope backslope on hill Effective annual precipitation: 20 to 25 inches Slope: 15 to 35 percent Frost-free period: 50 to 70 days Elevation: 5,300 to 6,200 feet Surface layer texture: Loam Effective annual precipitation: 17 to 20 inches Depth to bedrock (paralithic): 20 to 40 inches Frost-free period: 70 to 90 days Drainage class: Well drained Surface layer texture: Gravelly loam Parent material: Loamy residuum weathered from Drainage class: Well drained sandstone and siltstone Parent material: Gravelly alluvium Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 4.6 inches Available water capacity: Mainly 4.3 inches Gilispie and similar soils Additional Components Composition: 20 percent Winspect and similar soils: 4 percent Geomorphic description: • Mountaintop summit on mountain Management • Mountaintop shoulder on mountain For management information about this map unit, • Mountainflank shoulder on mountain see appropriate sections in Part II of this publication. Slope: 2 to 15 percent Elevation: 6,000 to 7,500 feet Effective annual precipitation: 20 to 25 inches 347D—Cheadle-Lymanson-Gilispie Frost-free period: 50 to 70 days complex, 2 to 15 percent slopes Surface layer texture: Gravelly loam Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Setting Parent material: Clayey residuum weathered from sandstone Elevation: 6,000 to 7,500 feet Native plant cover type: Rangeland Mean annual precipitation: 20 to 25 inches Available water capacity: Mainly 2.0 inches Frost-free period: 50 to 70 days Additional Components Major Component Description Adel and similar soils: 5 percent Bridger and similar soils: 5 percent Cheadle and similar soils Composition: 40 percent Management Geomorphic description: For management information about this map unit, • Mountaintop summit on mountain see appropriate sections in Part II of this publication. • Mountaintop shoulder on mountain Slope: 2 to 15 percent Elevation: 6,000 to 7,500 feet 347E—Cheadle-Lymanson-Gilispie Effective annual precipitation: 20 to 25 inches complex, 15 to 35 percent slopes Frost-free period: 50 to 70 days Surface layer texture: Channery loam Setting Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Elevation: 6,000 to 7,500 feet Parent material: Residuum weathered from Mean annual precipitation: 20 to 25 inches sandstone or gabbro Frost-free period: 50 to 70 days Sweet Grass County Area, Montana—Part I 263

Major Component Description Additional Components Lymanson and similar soils Adel and similar soils: 4 percent Composition: 40 percent Bridger and similar soils: 4 percent Geomorphic description: Mountainflank backslope on Rock outcrop: 2 percent mountain Management Slope: 15 to 35 percent Elevation: 6,000 to 7,500 feet For management information about this map unit, Effective annual precipitation: 20 to 25 inches see appropriate sections in Part II of this publication. Frost-free period: 50 to 70 days Surface layer texture: Loam Depth to bedrock (paralithic): 20 to 40 inches 348E—Lymanson-Cheadle-Adel complex, Drainage class: Well drained 8 to 35 percent slopes Parent material: Loamy residuum weathered from sandstone and siltstone Setting Native plant cover type: Rangeland Available water capacity: Mainly 4.6 inches Field investigation intensity: Order 2 Elevation: 6,000 to 7,500 feet Cheadle and similar soils Mean annual precipitation: 20 to 25 inches Composition: 30 percent Frost-free period: 50 to 70 days Geomorphic description: Major Component Description • Mountaintop summit on mountain • Mountaintop shoulder on mountain Lymanson and similar soils Slope: 15 to 35 percent Composition: 40 percent Elevation: 6,000 to 7,500 feet Geomorphic description: Mountainflank backslope on Effective annual precipitation: 20 to 25 inches mountain Frost-free period: 50 to 70 days Slope: 8 to 35 percent Surface layer texture: Channery loam Elevation: 6,000 to 7,500 feet Depth to bedrock (lithic): 10 to 20 inches Effective annual precipitation: 20 to 25 inches Drainage class: Well drained Frost-free period: 50 to 70 days Parent material: Residuum weathered from Surface layer texture: Loam sandstone Depth to bedrock (paralithic): 20 to 40 inches Native plant cover type: Rangeland Drainage class: Well drained Available water capacity: Mainly 1.1 inches Parent material: Loamy residuum weathered from sandstone and siltstone Gilispie and similar soils Native plant cover type: Rangeland Composition: 20 percent Available water capacity: Mainly 4.6 inches Geomorphic description: • Mountaintop summit on mountain Cheadle and similar soils • Mountaintop shoulder on mountain Composition: 30 percent • Mountainflank shoulder on mountain Geomorphic description: Slope: 15 to 35 percent • Mountaintop summit on mountain Elevation: 6,000 to 7,500 feet • Mountaintop shoulder on mountain Effective annual precipitation: 20 to 25 inches Slope: 8 to 35 percent Frost-free period: 50 to 70 days Elevation: 6,000 to 7,500 feet Surface layer texture: Gravelly loam Effective annual precipitation: 20 to 25 inches Depth to bedrock (lithic): 10 to 20 inches Frost-free period: 50 to 70 days Drainage class: Well drained Surface layer texture: Channery loam Parent material: Clayey residuum weathered from Depth to bedrock (lithic): 10 to 20 inches sandstone Drainage class: Well drained Native plant cover type: Rangeland Parent material: Residuum weathered from Available water capacity: Mainly 2.0 inches sandstone 264 Soil Survey

Native plant cover type: Rangeland Additional Components Available water capacity: Mainly 1.1 inches Gilispie and similar soils: 5 percent Lymanson and similar soils: 4 percent Adel and similar soils Merino and similar soils: 4 percent Composition: 20 percent Tongue River and similar soils: 2 percent Geomorphic description: Mountain and swale Slope: 8 to 35 percent Management Elevation: 6,000 to 7,500 feet For management information about this map unit, Effective annual precipitation: 20 to 25 inches see appropriate sections in Part II of this publication. Frost-free period: 50 to 70 days Surface layer texture: Loam Drainage class: Well drained 350F—Castner-Mowbray-Rock outcrop Parent material: Loamy alluvium or colluvium complex, 25 to 60 percent slopes Native plant cover type: Rangeland Available water capacity: Mainly 10.2 inches Setting Additional Components Field investigation intensity: Order 2 Bridger and similar soils: 4 percent Elevation: 5,300 to 6,200 feet Pintlar and similar soils: 4 percent Mean annual precipitation: 17 to 20 inches Gilispie and similar soils: 2 percent Frost-free period: 70 to 90 days Management Major Component Description For management information about this map unit, Castner and similar soils see appropriate sections in Part II of this publication. Composition: 40 percent Geomorphic description: • Nose slope summit on escarpment 349D—Cheadle channery loam, • Nose slope shoulder on escarpment 2 to 15 percent slopes Slope: 25 to 60 percent Elevation: 5,300 to 6,200 feet Effective annual precipitation: 17 to 20 inches Setting Frost-free period: 70 to 90 days Surface layer texture: Channery loam Elevation: 6,000 to 7,500 feet Depth to bedrock (lithic): 10 to 20 inches Mean annual precipitation: 20 to 25 inches Drainage class: Well drained Frost-free period: 50 to 70 days Parent material: Residuum weathered from sandstone Major Component Description Native plant cover type: Rangeland Cheadle and similar soils Available water capacity: Mainly 1.4 inches Composition: 85 percent Geomorphic description: Mowbray and similar soils • Mountaintop summit on mountain Composition: 32 percent • Mountaintop shoulder on mountain Geomorphic description: Base slope on escarpment Slope: 2 to 15 percent and fan Elevation: 6,000 to 7,500 feet Slope: 25 to 60 percent Effective annual precipitation: 20 to 25 inches Elevation: 5,300 to 6,200 feet Frost-free period: 50 to 70 days Effective annual precipitation: 17 to 20 inches Surface layer texture: Channery loam Frost-free period: 70 to 90 days Depth to bedrock (lithic): 10 to 20 inches Surface layer texture: Channery loam Drainage class: Well drained Drainage class: Well drained Parent material: Residuum weathered from Parent material: Gravelly colluvium weathered from sandstone calcareous sandstone Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 1.4 inches Available water capacity: Mainly 4.7 inches Sweet Grass County Area, Montana—Part I 265

Rock outcrop Depth to bedrock (lithic): 20 to 40 inches Composition: 20 percent Drainage class: Well drained Definition: Rock outcrop consists mainly of areas of Parent material: Residuum weathered from tuff exposed hard bedrock. breccia Geomorphic description: Escarpment Native plant cover type: Rangeland Available water capacity: Mainly 5.2 inches Additional Components Additional Components Winspect and similar soils: 3 percent Perma and similar soils: 2 percent Ashbon and similar soils: 5 percent Reedwest and similar soils: 2 percent Weedzunit and similar soils: 5 percent Wayden and similar soils: 1 percent Management Management For management information about this map unit, For management information about this map unit, see appropriate sections in Part II of this publication. see appropriate sections in Part II of this publication. 351E—Whitlash-Pianohill complex, 351D—Whitlash-Pianohill complex, 15 to 35 percent slopes 4 to 15 percent slopes Setting Setting Field investigation intensity: Order 2 Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Major Component Description Major Component Description Whitlash and similar soils Whitlash and similar soils Composition: 50 percent Composition: 50 percent Geomorphic description: Geomorphic description: • Nose slope shoulder on hill • Nose slope summit on hill • Nose slope summit on hill • Nose slope shoulder on hill Slope: 4 to 15 percent Slope: 15 to 45 percent Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Surface layer texture: Gravelly loam Surface layer texture: Gravelly loam Depth to bedrock (lithic): 10 to 20 inches Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained Parent material: Residuum weathered from tuff Parent material: Residuum weathered from tuff breccia breccia Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 2.0 inches Available water capacity: Mainly 2.0 inches

Pianohill and similar soils Pianohill and similar soils Composition: 40 percent Composition: 40 percent Geomorphic description: Geomorphic description: • Side slope backslope on hill • Side slope backslope on hill • Base slope backslope on hill • Base slope backslope on hill • Base slope footslope on hill • Base slope footslope on hill Slope: 4 to 15 percent Slope: 15 to 35 percent Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Surface layer texture: Loam Surface layer texture: Loam 266 Soil Survey

Depth to bedrock (lithic): 20 to 40 inches Management Drainage class: Well drained For management information about this map unit, Parent material: Residuum weathered from tuff see appropriate sections in Part II of this publication. breccia Native plant cover type: Rangeland Available water capacity: Mainly 5.2 inches 353F—Ashbon-Rock outcrop-Winkler Additional Components complex, 35 to 60 percent slopes Ashbon and similar soils: 5 percent Setting Weedzunit and similar soils: 5 percent Elevation: 3,900 to 6,000 feet Management Mean annual precipitation: 15 to 19 inches For management information about this map unit, Frost-free period: 85 to 115 days see appropriate sections in Part II of this publication. Major Component Description Ashbon and similar soils 352E—Perma-Rock outcrop complex, Composition: 40 percent 15 to 45 percent slopes Geomorphic description: • Nose slope summit on hill • Nose slope shoulder on hill Setting Slope: 35 to 60 percent Elevation: 5,300 to 6,200 feet Elevation: 3,900 to 6,000 feet Mean annual precipitation: 17 to 20 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 70 to 90 days Frost-free period: 85 to 115 days Surface layer texture: Very gravelly sandy loam Major Component Description Depth to bedrock (lithic): 10 to 20 inches Perma and similar soils Drainage class: Well drained Composition: 70 percent Parent material: Residuum weathered from tuff Geomorphic description: breccia • Base slope footslope on hill Native plant cover type: Forestland • Base slope toeslope on hill Available water capacity: Mainly 1.2 inches • Side slope backslope on hill Slope: 15 to 45 percent Rock outcrop Elevation: 5,300 to 6,200 feet Composition: 30 percent Effective annual precipitation: 17 to 20 inches Definition: Rock outcrop consists mainly of areas of Frost-free period: 70 to 90 days exposed hard bedrock. Surface layer texture: Cobbly loam Geomorphic description: Hill Drainage class: Somewhat excessively drained Parent material: Gravelly colluvium Winkler and similar soils Native plant cover type: Rangeland Composition: 20 percent Available water capacity: Mainly 4.6 inches Geomorphic description: • Side slope backslope on hill Rock outcrop • Base slope footslope on hill Composition: 15 percent • Base slope backslope on hill Definition: Rock outcrop consists mainly of areas of Slope: 35 to 60 percent exposed hard bedrock. Elevation: 3,900 to 6,000 feet Geomorphic description: Hill Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Additional Components Surface layer texture: Very gravelly sandy loam Breeton and similar soils: 5 percent Drainage class: Somewhat excessively drained Shambo and similar soils: 5 percent Parent material: Gravelly colluvium weathered from Weedzunit and similar soils: 5 percent tuff breccia Sweet Grass County Area, Montana—Part I 267

Native plant cover type: Forestland Rock outcrop Available water capacity: Mainly 3.6 inches Composition: 20 percent Definition: Rock outcrop consists mainly of areas of Additional Components exposed hard bedrock. Sweetweed and similar soils: 5 percent Geomorphic description: Hill Whitlash and similar soils: 5 percent Additional Components Management Sweetweed and similar soils: 4 percent For management information about this map unit, Ashbon and similar soils: 3 percent see appropriate sections in Part II of this publication. Winkler and similar soils: 3 percent Management 354F—Vision-Whitlash-Rock outcrop For management information about this map unit, complex, 35 to 60 percent slopes see appropriate sections in Part II of this publication.

Setting 355F—Doney-Cabba, moist loams, Elevation: 3,900 to 6,000 feet 35 to 60 percent slopes Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Setting Major Component Description Elevation: 3,900 to 6,000 feet Vision and similar soils Mean annual precipitation: 15 to 19 inches Composition: 40 percent Frost-free period: 85 to 115 days Geomorphic description: Major Component Description • Base slope backslope on hill • Base slope footslope on hill Doney and similar soils Slope: 35 to 60 percent Composition: 50 percent Elevation: 3,900 to 6,000 feet Geomorphic description: Effective annual precipitation: 15 to 19 inches • Base slope footslope on escarpment Frost-free period: 85 to 115 days • Base slope backslope on escarpment Surface layer texture: Gravelly loam • Side slope backslope on escarpment Drainage class: Well drained Slope: 35 to 60 percent Parent material: Gravelly colluvium weathered from Elevation: 3,900 to 6,000 feet tuff breccia Effective annual precipitation: 15 to 19 inches Native plant cover type: Forestland Frost-free period: 85 to 115 days Available water capacity: Mainly 5.8 inches Surface layer texture: Loam Depth to bedrock (paralithic): 20 to 40 inches Whitlash and similar soils Drainage class: Well drained Composition: 30 percent Parent material: Loamy residuum weathered from Geomorphic description: sandstone and siltstone • Nose slope summit on hill Native plant cover type: Rangeland • Nose slope shoulder on hill Available water capacity: Mainly 4.6 inches Slope: 35 to 60 percent Elevation: 3,900 to 6,000 feet Cabba and similar soils Effective annual precipitation: 15 to 19 inches Composition: 40 percent Frost-free period: 85 to 115 days Geomorphic description: Surface layer texture: Gravelly loam • Nose slope backslope on escarpment Depth to bedrock (lithic): 10 to 20 inches • Nose slope summit on escarpment Drainage class: Well drained • Side slope backslope on escarpment Parent material: Residuum weathered from tuff Slope: 35 to 60 percent breccia Elevation: 3,900 to 6,000 feet Native plant cover type: Forestland Effective annual precipitation: 15 to 19 inches Available water capacity: Mainly 2.0 inches Frost-free period: 85 to 115 days 268 Soil Survey

Surface layer texture: Loam 357D—Cabba-Vershal complex, Depth to bedrock (paralithic): 10 to 20 inches 4 to 15 percent slopes Drainage class: Well drained Parent material: Loamy residuum weathered from Setting sandstone and siltstone Native plant cover type: Forestland Field investigation intensity: Order 2 Available water capacity: Mainly 2.0 inches Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Additional Components Frost-free period: 85 to 115 days Castner and similar soils: 5 percent Major Component Description Macar and similar soils: 5 percent Cabba and similar soils Management Composition: 50 percent For management information about this map unit, Geomorphic description: Knoll and plain see appropriate sections in Part II of this publication. Slope: 4 to 15 percent Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches 356D—Redchief gravelly loam, Frost-free period: 85 to 115 days 4 to 15 percent slopes Surface layer texture: Loam Depth to bedrock (paralithic): 10 to 20 inches Drainage class: Well drained Setting Parent material: Loamy residuum weathered from sandstone and siltstone Elevation: 6,000 to 7,500 feet Native plant cover type: Rangeland Mean annual precipitation: 20 to 25 inches Available water capacity: Mainly 2.5 inches Frost-free period: 50 to 70 days Vershal and similar soils Major Component Description Composition: 40 percent Redchief and similar soils Geomorphic description: Knoll and plain Composition: 90 percent Slope: 4 to 15 percent Geomorphic description: Microhigh on outwash plain Elevation: 4,200 to 6,000 feet Slope: 4 to 15 percent Effective annual precipitation: 15 to 19 inches Elevation: 6,000 to 7,500 feet Frost-free period: 85 to 115 days Effective annual precipitation: 20 to 25 inches Surface layer texture: Very channery loam Frost-free period: 50 to 70 days Depth to bedrock (lithic): 4 to 10 inches Surface layer texture: Gravelly loam Drainage class: Well drained Drainage class: Well drained Parent material: Residuum weathered from Parent material: Gravelly glaciofluvial deposits sandstone Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 4.9 inches Available water capacity: Mainly 0.6 inches Additional Components Additional Components Libeg and similar soils: 4 percent Amherst and similar soils: 5 percent Adel and similar soils: 3 percent Reedwest and similar soils: 3 percent Melville and similar soils: 3 percent Beenom and similar soils: 2 percent Management Management For management information about this map unit, For management information about this map unit, see appropriate sections in Part II of this publication. see appropriate sections in Part II of this publication. Sweet Grass County Area, Montana—Part I 269

357E—Cabba-Vershal complex, Management 15 to 45 percent slopes For management information about this map unit, see appropriate sections in Part II of this publication. Setting Elevation: 3,900 to 6,000 feet 358E—Tongue River-Danaher loams, Mean annual precipitation: 15 to 19 inches 15 to 35 percent slopes Frost-free period: 85 to 115 days Major Component Description Setting Cabba and similar soils Elevation: 5,500 to 7,500 feet Composition: 50 percent Mean annual precipitation: 20 to 25 inches Geomorphic description: Frost-free period: 50 to 70 days • Nose slope summit on hill Major Component Description • Nose slope backslope on hill • Side slope backslope on hill Tongue River and similar soils Slope: 15 to 45 percent Composition: 50 percent Elevation: 3,900 to 6,000 feet Geomorphic description: Effective annual precipitation: 15 to 19 inches • Mountainflank backslope on mountain Frost-free period: 85 to 115 days • Mountainflank footslope on mountain Surface layer texture: Loam Slope: 15 to 35 percent Depth to bedrock (paralithic): 10 to 20 inches Elevation: 5,500 to 7,500 feet Drainage class: Well drained Effective annual precipitation: 20 to 25 inches Parent material: Loamy residuum weathered from Frost-free period: 50 to 70 days sandstone and siltstone Surface layer texture: Loam Native plant cover type: Rangeland Depth to bedrock (paralithic): 20 to 40 inches Available water capacity: Mainly 2.5 inches Drainage class: Well drained Parent material: Loamy residuum weathered from Vershal and similar soils sandstone and siltstone Composition: 40 percent Native plant cover type: Forestland Geomorphic description: Available water capacity: Mainly 5.8 inches • Nose slope summit on hill • Nose slope shoulder on hill Danaher and similar soils Slope: 15 to 45 percent Composition: 40 percent Elevation: 3,900 to 6,000 feet Geomorphic description: Effective annual precipitation: 15 to 19 inches • Mountainbase footslope on mountain Frost-free period: 85 to 115 days • Mountainbase toeslope on mountain Surface layer texture: Very channery loam Slope: 15 to 35 percent Depth to bedrock (lithic): 4 to 10 inches Elevation: 5,500 to 7,500 feet Drainage class: Well drained Effective annual precipitation: 20 to 25 inches Parent material: Residuum weathered from Frost-free period: 50 to 70 days sandstone Surface layer texture: Loam Native plant cover type: Rangeland Drainage class: Well drained Available water capacity: Mainly 0.6 inches Parent material: Silty and clayey colluvium or alluvium Native plant cover type: Forestland Additional Components Available water capacity: Mainly 9.3 inches Doney and similar soils: 4 percent Additional Components Rock outcrop: 3 percent Macar and similar soils: 2 percent Cheadle and similar soils: 5 percent Farnuf and similar soils: 1 percent Knep and similar soils: 5 percent 270 Soil Survey

Management Slope: 25 to 45 percent Elevation: 5,500 to 7,500 feet For management information about this map unit, Effective annual precipitation: 20 to 25 inches see appropriate sections in Part II of this publication. Frost-free period: 50 to 70 days Surface layer texture: Loam 359F—Fifer-Cheadle-Monaberg complex, Drainage class: Well drained 25 to 60 percent slopes Parent material: Loamy alluvium or colluvium Native plant cover type: Forestland Available water capacity: Mainly 9.0 inches Setting Elevation: 5,500 to 7,500 feet Additional Components Mean annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Adel and similar soils: 3 percent Knep and similar soils: 2 percent Major Component Description Management Fifer and similar soils Composition: 40 percent For management information about this map unit, Geomorphic description: see appropriate sections in Part II of this publication. • Mountaintop summit on mountain • Mountaintop shoulder on mountain • Mountainflank shoulder on mountain 360D—Knep family-Warwood loams, Slope: 35 to 60 percent 4 to 15 percent slopes Elevation: 5,500 to 7,500 feet Effective annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Setting Surface layer texture: Loam Elevation: 6,000 to 7,500 feet Depth to bedrock (paralithic): 10 to 20 inches Mean annual precipitation: 20 to 25 inches Drainage class: Well drained Frost-free period: 50 to 70 days Parent material: Loamy residuum weathered from sandstone and shale Major Component Description Native plant cover type: Rangeland Available water capacity: Mainly 2.7 inches Knep and similar soils Composition: 50 percent Cheadle and similar soils Geomorphic description: Composition: 30 percent • Mountainbase toeslope on mountain Geomorphic description: • Mountainflank backslope on mountain • Mountaintop summit on mountain Slope: 8 to 15 percent • Mountaintop shoulder on mountain Elevation: 6,000 to 7,500 feet Slope: 35 to 60 percent Effective annual precipitation: 20 to 25 inches Elevation: 5,500 to 7,500 feet Frost-free period: 50 to 70 days Effective annual precipitation: 20 to 25 inches Surface layer texture: Loam Frost-free period: 50 to 70 days Drainage class: Well drained Surface layer texture: Channery loam Parent material: Loamy alluvium or colluvium Depth to bedrock (lithic): 10 to 20 inches Native plant cover type: Forestland Drainage class: Well drained Available water capacity: Mainly 9.7 inches Parent material: Residuum weathered from sandstone Warwood and similar soils Native plant cover type: Rangeland Composition: 40 percent Available water capacity: Mainly 1.1 inches Geomorphic description: • Mountainbase footslope on mountain Monaberg and similar soils • Mountainbase toeslope on mountain Composition: 25 percent Slope: 4 to 15 percent Geomorphic description: Mountainbase toeslope on Elevation: 6,000 to 7,500 feet mountain Effective annual precipitation: 20 to 25 inches Sweet Grass County Area, Montana—Part I 271

Frost-free period: 50 to 70 days 362F—Wayden-Castner-Rock outcrop Surface layer texture: Loam complex, 25 to 60 percent slopes Drainage class: Well drained Parent material: Loamy alluvium Setting Native plant cover type: Forestland Available water capacity: Mainly 9.3 inches Field investigation intensity: Order 2 Elevation: 2,620 to 6,000 feet Additional Components Mean annual precipitation: 15 to 19 inches Danaher and similar soils: 5 percent Frost-free period: 85 to 115 days Monaberg and similar soils: 5 percent Major Component Description Management Wayden and similar soils For management information about this map unit, Composition: 40 percent see appropriate sections in Part II of this publication. Geomorphic description: • Side slope shoulder on escarpment • Nose slope summit on escarpment 361E—Cowood very channery loam, • Nose slope shoulder on escarpment 4 to 25 percent slopes Slope: 25 to 60 percent Elevation: 2,620 to 4,590 feet Effective annual precipitation: 15 to 19 inches Setting Frost-free period: 85 to 115 days Elevation: 5,500 to 7,500 feet Surface layer texture: Clay Mean annual precipitation: 20 to 25 inches Depth to bedrock (paralithic): 10 to 20 inches Frost-free period: 50 to 70 days Drainage class: Well drained Parent material: Clayey residuum weathered from Major Component Description shale and siltstone Cowood and similar soils Native plant cover type: Rangeland Composition: 85 percent Available water capacity: Mainly 2.7 inches Geomorphic description: • Mountaintop summit on mountain Castner and similar soils • Mountaintop shoulder on mountain Composition: 30 percent Slope: 4 to 25 percent Geomorphic description: Elevation: 5,500 to 7,500 feet • Nose slope summit on escarpment Effective annual precipitation: 20 to 25 inches • Nose slope shoulder on escarpment Frost-free period: 50 to 70 days Slope: 25 to 60 percent Surface layer texture: Very channery loam Elevation: 4,200 to 6,000 feet Depth to bedrock (lithic): 10 to 20 inches Effective annual precipitation: 15 to 19 inches Drainage class: Well drained Frost-free period: 85 to 115 days Parent material: Residuum weathered from Surface layer texture: Very channery loam sandstone over gabbro Depth to bedrock (lithic): 10 to 20 inches Native plant cover type: Forestland Drainage class: Well drained Available water capacity: Mainly 1.6 inches Parent material: Residuum weathered from sandstone Additional Components Native plant cover type: Rangeland Arrowpeak and similar soils: 5 percent Available water capacity: Mainly 1.3 inches Timberlin and similar soils: 5 percent Worock and similar soils: 5 percent Rock outcrop Composition: 20 percent Management Definition: Rock outcrop consists mainly of areas of For management information about this map unit, exposed hard bedrock. see appropriate sections in Part II of this publication. Geomorphic description: Escarpment 272 Soil Survey

Additional Components Megonot and similar soils Composition: 20 percent Sagedale and similar soils: 5 percent Geomorphic description: Winifred and similar soils: 5 percent • Base slope backslope on hill Management • Base slope footslope on hill • Side slope backslope on hill For management information about this map unit, Slope: 8 to 25 percent see appropriate sections in Part II of this publication. Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days 363E—Kobase-Rentsac-Megonot Surface layer texture: Clay loam complex, 4 to 25 percent slopes Depth to bedrock (paralithic): 20 to 40 inches Drainage class: Well drained Parent material: Clayey residuum weathered from Setting shale Field investigation intensity: Order 2 Native plant cover type: Rangeland Elevation: 3,750 to 5,200 feet Available water capacity: Mainly 3.9 inches Mean annual precipitation: 10 to 14 inches Additional Components Frost-free period: 95 to 125 days Richey and similar soils: 3 percent Major Component Description Yamacall and similar soils: 3 percent Kobase and similar soils Cabbart and similar soils: 2 percent Composition: 40 percent Delpoint and similar soils: 1 percent Geomorphic description: Reedpoint and similar soils: 1 percent • Base slope footslope on hill Management • Base slope toeslope on hill Slope: 4 to 15 percent For management information about this map unit, Elevation: 3,750 to 5,200 feet see appropriate sections in Part II of this publication. Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Surface layer texture: Clay loam 364E—Absarokee-Bowery loams, Drainage class: Well drained 15 to 45 percent slopes Parent material: Clayey alluvium weathered from shale and siltstone Setting Native plant cover type: Rangeland Available water capacity: Mainly 9.4 inches Elevation: 5,300 to 6,200 feet Mean annual precipitation: 17 to 20 inches Rentsac and similar soils Frost-free period: 70 to 90 days Composition: 30 percent Major Component Description Geomorphic description: • Nose slope summit on hill Absarokee and similar soils • Nose slope shoulder on hill Composition: 60 percent Slope: 4 to 25 percent Geomorphic description: Elevation: 3,750 to 5,200 feet • Side slope backslope on hill Effective annual precipitation: 10 to 14 inches • Base slope backslope on hill Frost-free period: 95 to 125 days • Base slope footslope on hill Surface layer texture: Very channery loam Slope: 15 to 45 percent Depth to bedrock (lithic): 10 to 20 inches Elevation: 5,300 to 6,200 feet Drainage class: Well drained Effective annual precipitation: 17 to 20 inches Parent material: Residuum weathered from Frost-free period: 70 to 90 days calcareous sandstone Surface layer texture: Loam Native plant cover type: Rangeland Depth to bedrock (lithic): 20 to 40 inches Available water capacity: Mainly 1.3 inches Drainage class: Well drained Sweet Grass County Area, Montana—Part I 273

Parent material: Silty and clayey residuum weathered Cabbart and similar soils from sandstone and shale Composition: 40 percent Native plant cover type: Rangeland Geomorphic description: Knoll and plain Available water capacity: Mainly 4.1 inches Slope: 2 to 8 percent Elevation: 3,750 to 5,200 feet Bowery and similar soils Effective annual precipitation: 10 to 14 inches Composition: 30 percent Frost-free period: 95 to 125 days Geomorphic description: Hill and swale Surface layer texture: Loam Slope: 15 to 35 percent Depth to bedrock (paralithic): 10 to 20 inches Elevation: 5,300 to 6,200 feet Drainage class: Well drained Effective annual precipitation: 17 to 20 inches Parent material: Loamy residuum weathered from Frost-free period: 70 to 90 days sandstone and siltstone Surface layer texture: Loam Native plant cover type: Rangeland Drainage class: Well drained Available water capacity: Mainly 3.0 inches Parent material: Loamy alluvium or colluvium Additional Components Native plant cover type: Rangeland Available water capacity: Mainly 10.6 inches Kobase and similar soils: 4 percent Yawdim and similar soils: 4 percent Additional Components Delpoint and similar soils: 2 percent Bacbuster and similar soils: 3 percent Management Work and similar soils: 3 percent Farnuf and similar soils: 2 percent For management information about this map unit, Reedwest and similar soils: 2 percent see appropriate sections in Part II of this publication. Management For management information about this map unit, 366C—Tanna, calcareous,-Rentsac see appropriate sections in Part II of this publication. complex, 2 to 8 percent slopes

Setting 365C—Megonot-Cabbart complex, Elevation: 3,750 to 5,200 feet 2 to 8 percent slopes Mean annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Setting Major Component Description Elevation: 3,750 to 5,200 feet Tanna, calcareous and similar soils Mean annual precipitation: 10 to 14 inches Composition: 50 percent Frost-free period: 95 to 125 days Geomorphic description: Plain and swale Slope: 2 to 8 percent Major Component Description Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Megonot and similar soils Frost-free period: 95 to 125 days Composition: 50 percent Surface layer texture: Clay loam Geomorphic description: Plain and swale Depth to bedrock (paralithic): 20 to 40 inches Slope: 2 to 8 percent Drainage class: Well drained Elevation: 3,750 to 5,200 feet Parent material: Clayey residuum weathered from Effective annual precipitation: 10 to 14 inches sandstone and shale Frost-free period: 95 to 125 days Native plant cover type: Rangeland Surface layer texture: Clay loam Available water capacity: Mainly 4.2 inches Depth to bedrock (paralithic): 20 to 40 inches Drainage class: Well drained Rentsac and similar soils Parent material: Clayey residuum weathered from Composition: 40 percent shale Geomorphic description: Knoll and plain Native plant cover type: Rangeland Slope: 2 to 8 percent Available water capacity: Mainly 3.9 inches Elevation: 3,750 to 5,200 feet 274 Soil Survey

Effective annual precipitation: 10 to 14 inches Parent material: Residuum weathered from Frost-free period: 95 to 125 days calcareous sandstone Surface layer texture: Very channery loam Native plant cover type: Rangeland Depth to bedrock (lithic): 10 to 20 inches Available water capacity: Mainly 1.3 inches Drainage class: Well drained Additional Components Parent material: Residuum weathered from calcareous sandstone Greybear and similar soils: 4 percent Native plant cover type: Rangeland Reedpoint and similar soils: 3 percent Available water capacity: Mainly 1.3 inches Yawdim and similar soils: 3 percent Additional Components Management Greybear and similar soils: 4 percent For management information about this map unit, Reedpoint and similar soils: 3 percent see appropriate sections in Part II of this publication. Yawdim and similar soils: 3 percent Management 367D—Rentsac-Reedpoint complex, For management information about this map unit, 2 to 15 percent slopes see appropriate sections in Part II of this publication.

Setting 366D—Tanna, calcareous,-Rentsac complex, 8 to 15 percent slopes Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Setting Major Component Description Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Rentsac and similar soils Frost-free period: 95 to 125 days Composition: 50 percent Geomorphic description: Knoll and plain Major Component Description Slope: 2 to 15 percent Tanna, calcareous and similar soils Elevation: 3,750 to 5,200 feet Composition: 50 percent Effective annual precipitation: 10 to 14 inches Geomorphic description: Plain and swale Frost-free period: 95 to 125 days Slope: 8 to 15 percent Surface layer texture: Channery loam Elevation: 3,750 to 5,200 feet Depth to bedrock (lithic): 10 to 20 inches Effective annual precipitation: 10 to 14 inches Drainage class: Well drained Frost-free period: 95 to 125 days Parent material: Residuum weathered from Surface layer texture: Clay loam calcareous sandstone Depth to bedrock (paralithic): 20 to 40 inches Native plant cover type: Rangeland Drainage class: Well drained Available water capacity: Mainly 1.4 inches Parent material: Clayey residuum weathered from sandstone and shale Reedpoint and similar soils Native plant cover type: Rangeland Composition: 40 percent Available water capacity: Mainly 4.2 inches Geomorphic description: Knoll and plain Slope: 2 to 15 percent Rentsac and similar soils Elevation: 3,750 to 5,200 feet Composition: 40 percent Effective annual precipitation: 10 to 14 inches Geomorphic description: Knoll and plain Frost-free period: 95 to 125 days Slope: 8 to 15 percent Surface layer texture: Very channery loam Elevation: 3,750 to 5,200 feet Depth to bedrock (lithic): 4 to 10 inches Effective annual precipitation: 10 to 14 inches Drainage class: Well drained Frost-free period: 95 to 125 days Parent material: Residuum weathered from Surface layer texture: Very channery loam sandstone Depth to bedrock (lithic): 10 to 20 inches Native plant cover type: Rangeland Drainage class: Well drained Available water capacity: Mainly 0.4 inches Sweet Grass County Area, Montana—Part I 275

Additional Components Additional Components Cabbart and similar soils: 4 percent Cabbart and similar soils: 3 percent Delpoint and similar soils: 3 percent Delpoint and similar soils: 2 percent Yawdim and similar soils: 2 percent Megonot and similar soils: 2 percent Megonot and similar soils: 1 percent Yawdim and similar soils: 2 percent Rock outcrop: 1 percent Management Management For management information about this map unit, see appropriate sections in Part II of this publication. For management information about this map unit, see appropriate sections in Part II of this publication. 367E—Rentsac-Reedpoint complex, 15 to 35 percent slopes 368E—Rentsac-Tanna-Rock outcrop complex, 8 to 35 percent slopes Setting Setting Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Elevation: 3,750 to 5,200 feet Frost-free period: 95 to 125 days Mean annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Major Component Description Major Component Description Rentsac and similar soils Composition: 50 percent Rentsac and similar soils Geomorphic description: Composition: 40 percent • Nose slope summit on hill Geomorphic description: • Nose slope shoulder on hill • Nose slope summit on hill Slope: 15 to 35 percent • Nose slope shoulder on hill Elevation: 3,750 to 5,200 feet Slope: 8 to 35 percent Effective annual precipitation: 10 to 14 inches Elevation: 3,750 to 5,200 feet Frost-free period: 95 to 125 days Effective annual precipitation: 10 to 14 inches Surface layer texture: Channery loam Frost-free period: 95 to 125 days Depth to bedrock (lithic): 10 to 20 inches Surface layer texture: Very channery loam Drainage class: Well drained Depth to bedrock (lithic): 10 to 20 inches Parent material: Residuum weathered from Drainage class: Well drained calcareous sandstone Parent material: Residuum weathered from Native plant cover type: Rangeland calcareous sandstone Available water capacity: Mainly 1.4 inches Native plant cover type: Rangeland Available water capacity: Mainly 1.3 inches Reedpoint and similar soils Composition: 40 percent Tanna and similar soils Geomorphic description: Composition: 30 percent • Nose slope summit on hill Geomorphic description: • Nose slope shoulder on hill • Base slope footslope on hill Slope: 15 to 35 percent • Base slope backslope on hill Elevation: 3,750 to 5,200 feet • Side slope backslope on hill Effective annual precipitation: 10 to 14 inches Slope: 8 to 15 percent Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Surface layer texture: Very channery loam Effective annual precipitation: 10 to 14 inches Depth to bedrock (lithic): 4 to 10 inches Frost-free period: 95 to 125 days Drainage class: Well drained Surface layer texture: Clay loam Parent material: Residuum weathered from Depth to bedrock (paralithic): 20 to 40 inches sandstone Drainage class: Well drained Native plant cover type: Rangeland Parent material: Clayey residuum weathered from Available water capacity: Mainly 0.4 inches sandstone and shale 276 Soil Survey

Native plant cover type: Rangeland Depth to bedrock (paralithic): 20 to 40 inches Available water capacity: Mainly 4.2 inches Drainage class: Well drained Parent material: Clayey residuum weathered from Rock outcrop sandstone and shale Composition: 15 percent Native plant cover type: Rangeland Definition: Rock outcrop consists mainly of areas of Available water capacity: Mainly 4.2 inches exposed hard bedrock. Additional Components Geomorphic description: Hill Hinterland and similar soils: 4 percent Additional Components Cabbart and similar soils: 3 percent Cabbart and similar soils: 5 percent Reedpoint and similar soils: 2 percent Megonot and similar soils: 4 percent Ethridge and similar soils: 1 percent Ethridge and similar soils: 3 percent Management Yawdim and similar soils: 3 percent For management information about this map unit, Management see appropriate sections in Part II of this publication. For management information about this map unit, see appropriate sections in Part II of this publication. 369E—Rentsac-Tanna complex, 15 to 35 percent slopes 369D—Rentsac-Tanna complex, 2 to 15 percent slopes Setting Elevation: 3,750 to 5,200 feet Setting Mean annual precipitation: 10 to 14 inches Elevation: 3,750 to 5,200 feet Frost-free period: 95 to 125 days Mean annual precipitation: 10 to 14 inches Major Component Description Frost-free period: 95 to 125 days Rentsac and similar soils Major Component Description Composition: 50 percent Rentsac and similar soils Geomorphic description: Composition: 50 percent • Nose slope summit on hill Geomorphic description: Knoll and plain • Nose slope shoulder on hill Slope: 2 to 15 percent Slope: 15 to 35 percent Elevation: 3,750 to 5,200 feet Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Frost-free period: 95 to 125 days Surface layer texture: Very channery loam Surface layer texture: Very channery loam Depth to bedrock (lithic): 10 to 20 inches Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained Parent material: Residuum weathered from Parent material: Residuum weathered from calcareous sandstone calcareous sandstone Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 1.3 inches Available water capacity: Mainly 1.3 inches

Tanna and similar soils Tanna and similar soils Composition: 40 percent Composition: 40 percent Geomorphic description: Plain and swale Geomorphic description: Slope: 2 to 15 percent • Base slope footslope on hill Elevation: 3,750 to 5,200 feet • Base slope backslope on hill Effective annual precipitation: 10 to 14 inches • Side slope backslope on hill Frost-free period: 95 to 125 days Slope: 15 to 35 percent Surface layer texture: Clay loam Elevation: 3,750 to 5,200 feet Sweet Grass County Area, Montana—Part I 277

Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Frost-free period: 95 to 125 days Surface layer texture: Channery loam Surface layer texture: Clay loam Depth to bedrock (lithic): 10 to 20 inches Depth to bedrock (paralithic): 20 to 40 inches Drainage class: Well drained Drainage class: Well drained Parent material: Residuum weathered from Parent material: Clayey residuum weathered from calcareous sandstone sandstone and shale Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 1.4 inches Available water capacity: Mainly 4.2 inches Additional Components Additional Components Ethridge and similar soils: 4 percent Reedpoint and similar soils: 3 percent Megonot and similar soils: 2 percent Cabbart and similar soils: 2 percent Reedpoint and similar soils: 2 percent Ethridge and similar soils: 2 percent Yawdim and similar soils: 2 percent Hinterland and similar soils: 2 percent Management Rock outcrop: 1 percent For management information about this map unit, Management see appropriate sections in Part II of this publication. For management information about this map unit, see appropriate sections in Part II of this publication. 371D—Whitlash cobbly sandy loam, 2 to 15 percent slopes 370D—Greybear-Rentsac complex, 2 to 15 percent slopes Setting Elevation: 4,200 to 6,000 feet Setting Mean annual precipitation: 15 to 19 inches Elevation: 3,750 to 5,200 feet Frost-free period: 85 to 115 days Mean annual precipitation: 10 to 14 inches Major Component Description Frost-free period: 95 to 125 days Whitlash and similar soils Major Component Description Composition: 90 percent Greybear and similar soils Geomorphic description: Knoll and plain Composition: 50 percent Slope: 2 to 15 percent Geomorphic description: Plain and swale Elevation: 4,200 to 6,000 feet Slope: 2 to 8 percent Effective annual precipitation: 15 to 19 inches Elevation: 3,750 to 5,200 feet Frost-free period: 85 to 115 days Effective annual precipitation: 10 to 14 inches Surface layer texture: Gravelly loam Frost-free period: 95 to 125 days Depth to bedrock (lithic): 10 to 20 inches Surface layer texture: Clay loam Drainage class: Well drained Depth to bedrock (paralithic): 40 to 60 inches Parent material: Residuum weathered from gabbro Drainage class: Well drained Native plant cover type: Rangeland Parent material: Clayey alluvium over clayey Available water capacity: Mainly 2.0 inches residuum weathered from shale Additional Components Native plant cover type: Rangeland Available water capacity: Mainly 8.3 inches Beenom and similar soils: 4 percent Reedwest and similar soils: 3 percent Rentsac and similar soils Amherst and similar soils: 2 percent Composition: 40 percent Castner and similar soils: 1 percent Geomorphic description: Knoll and plain Management Slope: 2 to 15 percent Elevation: 3,750 to 5,200 feet For management information about this map unit, Effective annual precipitation: 10 to 14 inches see appropriate sections in Part II of this publication. 278 Soil Survey

371E—Whitlash cobbly sandy loam, Frost-free period: 85 to 115 days 15 to 35 percent slopes Surface layer texture: Channery loam Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Setting Parent material: Residuum weathered from Field investigation intensity: Order 2 sandstone Elevation: 4,200 to 6,000 feet Native plant cover type: Rangeland Mean annual precipitation: 15 to 19 inches Available water capacity: Mainly 1.6 inches Frost-free period: 85 to 115 days Amherst and similar soils Major Component Description Composition: 40 percent Whitlash and similar soils Geomorphic description: Knoll and plain Composition: 90 percent Slope: 2 to 15 percent Geomorphic description: Elevation: 4,200 to 6,000 feet • Nose slope summit on hill Effective annual precipitation: 15 to 19 inches • Nose slope shoulder on hill Frost-free period: 85 to 115 days Slope: 15 to 35 percent Surface layer texture: Gravelly clay loam Elevation: 4,200 to 6,000 feet Depth to bedrock (lithic): 10 to 20 inches Effective annual precipitation: 15 to 19 inches Drainage class: Well drained Frost-free period: 85 to 115 days Parent material: Clayey residuum weathered from Surface layer texture: Gravelly loam andesite Depth to bedrock (lithic): 10 to 20 inches Native plant cover type: Rangeland Drainage class: Well drained Available water capacity: Mainly 2.5 inches Parent material: Residuum weathered from gabbro Additional Components Native plant cover type: Rangeland Available water capacity: Mainly 2.0 inches Absarokee and similar soils: 3 percent Beenom and similar soils: 3 percent Additional Components Reedwest and similar soils: 2 percent Beenom and similar soils: 3 percent Rock outcrop: 2 percent Amherst and similar soils: 2 percent Management Castner and similar soils: 2 percent Reedwest and similar soils: 2 percent For management information about this map unit, Rock outcrop: 1 percent see appropriate sections in Part II of this publication. Management For management information about this map unit, 372E—Castner-Amherst complex, see appropriate sections in Part II of this publication. 15 to 35 percent slopes

Setting 372D—Castner-Amherst complex, 2 to 15 percent slopes Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Setting Major Component Description Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Castner and similar soils Frost-free period: 85 to 115 days Composition: 50 percent Geomorphic description: Major Component Description • Nose slope summit on hill Castner and similar soils • Nose slope shoulder on hill Composition: 50 percent Slope: 15 to 35 percent Geomorphic description: Knoll and plain Elevation: 4,200 to 6,000 feet Slope: 2 to 15 percent Effective annual precipitation: 15 to 19 inches Elevation: 4,200 to 6,000 feet Frost-free period: 85 to 115 days Effective annual precipitation: 15 to 19 inches Surface layer texture: Channery loam Sweet Grass County Area, Montana—Part I 279

Depth to bedrock (lithic): 10 to 20 inches Parent material: Residuum weathered from Drainage class: Well drained calcareous sandstone Parent material: Residuum weathered from Native plant cover type: Rangeland sandstone Available water capacity: Mainly 2.9 inches Native plant cover type: Rangeland Available water capacity: Mainly 1.4 inches Castner and similar soils Composition: 20 percent Amherst and similar soils Geomorphic description: Knoll and plain Composition: 40 percent Slope: 2 to 15 percent Geomorphic description: Elevation: 4,200 to 6,000 feet • Nose slope summit on hill Effective annual precipitation: 15 to 19 inches • Nose slope shoulder on hill Frost-free period: 85 to 115 days Slope: 15 to 35 percent Surface layer texture: Channery loam Elevation: 4,200 to 6,000 feet Depth to bedrock (lithic): 10 to 20 inches Effective annual precipitation: 15 to 19 inches Drainage class: Well drained Frost-free period: 85 to 115 days Parent material: Residuum weathered from Surface layer texture: Gravelly clay loam sandstone Depth to bedrock (lithic): 10 to 20 inches Native plant cover type: Rangeland Drainage class: Well drained Available water capacity: Mainly 1.6 inches Parent material: Clayey residuum weathered from Additional Components andesite Native plant cover type: Rangeland Doney and similar soils: 5 percent Available water capacity: Mainly 2.5 inches Cabba and similar soils: 3 percent Vershal and similar soils: 2 percent Additional Components Management Absarokee and similar soils: 3 percent Beenom and similar soils: 3 percent For management information about this map unit, Reedwest and similar soils: 2 percent see appropriate sections in Part II of this publication. Rock outcrop: 2 percent Management 374F—Cabbart, moist-Delpoint-Rock For management information about this map unit, outcrop complex, 15 to 45 percent see appropriate sections in Part II of this publication. slopes

373D—Ticell-Castner complex, Setting 2 to 15 percent slopes Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Setting Frost-free period: 95 to 125 days Elevation: 4,200 to 6,000 feet Major Component Description Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Cabbart and similar soils Composition: 40 percent Major Component Description Geomorphic description: Ticell and similar soils • Nose slope summit on escarpment Composition: 70 percent • Nose slope shoulder on escarpment Geomorphic description: Knoll and plain • Side slope backslope on escarpment Slope: 2 to 15 percent Slope: 15 to 45 percent Elevation: 4,200 to 6,000 feet Elevation: 3,750 to 5,200 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 10 to 14 inches Frost-free period: 85 to 115 days Frost-free period: 95 to 125 days Surface layer texture: Loam Surface layer texture: Loam Depth to bedrock (lithic): 10 to 20 inches Depth to bedrock (paralithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained 280 Soil Survey

Parent material: Loamy residuum weathered from Frost-free period: 95 to 125 days sandstone and siltstone Surface layer texture: Loam Native plant cover type: Forestland Depth to bedrock (paralithic): 10 to 20 inches Available water capacity: Mainly 3.0 inches Drainage class: Well drained Parent material: Loamy residuum weathered from Delpoint and similar soils sandstone and siltstone Composition: 30 percent Native plant cover type: Rangeland Geomorphic description: Available water capacity: Mainly 3.0 inches • Base slope backslope on escarpment • Base slope footslope on escarpment Rentsac and similar soils • Side slope backslope on escarpment Composition: 30 percent Slope: 15 to 35 percent Geomorphic description: Knoll and plain Elevation: 3,750 to 5,200 feet Slope: 2 to 15 percent Effective annual precipitation: 10 to 14 inches Elevation: 3,750 to 5,200 feet Frost-free period: 95 to 125 days Effective annual precipitation: 10 to 14 inches Surface layer texture: Loam Frost-free period: 95 to 125 days Depth to bedrock (paralithic): 20 to 40 inches Surface layer texture: Channery loam Drainage class: Well drained Depth to bedrock (lithic): 10 to 20 inches Parent material: Loamy residuum weathered from Drainage class: Well drained sandstone and siltstone Parent material: Residuum weathered from Native plant cover type: Rangeland calcareous sandstone Available water capacity: Mainly 3.8 inches Native plant cover type: Forestland Available water capacity: Mainly 1.4 inches Rock outcrop Additional Components Composition: 15 percent Definition: Rock outcrop consists mainly of areas of Blacksheep and similar soils: 3 percent exposed hard bedrock. Twilight and similar soils: 3 percent Geomorphic description: Escarpment Delpoint and similar soils: 2 percent Rock outcrop: 2 percent Additional Components Management Blacksheep and similar soils: 5 percent Twilight and similar soils: 5 percent For management information about this map unit, Yamacall and similar soils: 5 percent see appropriate sections in Part II of this publication. Management For management information about this map unit, 376E—Chinook-Twilight fine sandy loams, see appropriate sections in Part II of this publication. 8 to 25 percent slopes

Setting 375D—Cabbart-Rentsac, moist, complex, 2 to 15 percent slopes Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Setting Major Component Description Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Chinook and similar soils Frost-free period: 95 to 125 days Composition: 50 percent Geomorphic description: Major Component Description • Base slope footslope on hill Cabbart and similar soils • Base slope toeslope on hill Composition: 60 percent • Plain Geomorphic description: Knoll and plain • Swale Slope: 2 to 15 percent Slope: 8 to 25 percent Elevation: 3,750 to 5,200 feet Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Effective annual precipitation: 10 to 14 inches Sweet Grass County Area, Montana—Part I 281

Frost-free period: 95 to 125 days Major Component Description Surface layer texture: Fine sandy loam Tongue River and similar soils Drainage class: Well drained Composition: 50 percent Parent material: Sandy residuum weathered from Geomorphic description: sandstone • Mountainflank backslope on mountain Native plant cover type: Rangeland • Mountainflank footslope on mountain Available water capacity: Mainly 8.1 inches Slope: 15 to 60 percent Elevation: 5,500 to 7,500 feet Twilight and similar soils Effective annual precipitation: 20 to 25 inches Composition: 40 percent Frost-free period: 50 to 70 days Geomorphic description: Surface layer texture: Loam • Base slope backslope on hill Depth to bedrock (paralithic): 20 to 40 inches • Base slope footslope on hill Drainage class: Well drained • Side slope backslope on hill Parent material: Loamy residuum weathered from • Plain sandstone and siltstone • Swale Native plant cover type: Forestland Slope: 8 to 25 percent Available water capacity: Mainly 5.8 inches Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Fifer and similar soils Frost-free period: 95 to 125 days Composition: 25 percent Surface layer texture: Fine sandy loam Geomorphic description: Mountaintop summit on Depth to bedrock (paralithic): 20 to 40 inches mountain Drainage class: Well drained Slope: 15 to 60 percent Parent material: Sandy residuum weathered from Elevation: 5,500 to 7,500 feet calcareous sandstone Effective annual precipitation: 20 to 25 inches Native plant cover type: Rangeland Frost-free period: 50 to 70 days Available water capacity: Mainly 3.8 inches Surface layer texture: Loam Additional Components Depth to bedrock (paralithic): 10 to 20 inches Drainage class: Well drained Rentsac and similar soils: 4 percent Parent material: Loamy residuum weathered from Blacksheep and similar soils: 3 percent sandstone and siltstone Cabbart and similar soils: 3 percent Native plant cover type: Forestland Management Available water capacity: Mainly 2.7 inches For management information about this map unit, Adel and similar soils see appropriate sections in Part II of this publication. Composition: 15 percent Geomorphic description: Mountain and swale 377F—Tongue River-Cabba, moist-Adel Slope: 15 to 25 percent loams, 15 to 60 percent slopes Elevation: 5,500 to 7,500 feet Effective annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Setting Surface layer texture: Loam Field investigation intensity: Order 2 Drainage class: Well drained Elevation: 5,500 to 7,500 feet Parent material: Loamy alluvium or colluvium Mean annual precipitation: 20 to 25 inches Native plant cover type: Rangeland Frost-free period: 50 to 70 days Available water capacity: Mainly 10.2 inches 282 Soil Survey

Additional Components Major Component Description Knep and similar soils: 5 percent Tongue River and similar soils Monaberg and similar soils: 5 percent Composition: 60 percent Geomorphic description: Management • Mountainflank backslope on mountain For management information about this map unit, • Mountainflank footslope on mountain see appropriate sections in Part II of this publication. Slope: 15 to 60 percent Elevation: 5,500 to 7,500 feet Effective annual precipitation: 20 to 25 inches 378D—Melville cobbly loam, Frost-free period: 50 to 70 days 2 to 15 percent slopes, stony Surface layer texture: Loam Depth to bedrock (paralithic): 20 to 40 inches Setting Drainage class: Well drained Parent material: Loamy residuum weathered from Elevation: 6,000 to 7,500 feet sandstone and siltstone Mean annual precipitation: 20 to 25 inches Native plant cover type: Forestland Frost-free period: 50 to 70 days Available water capacity: Mainly 5.8 inches Major Component Description Arrowpeak and similar soils Melville and similar soils Composition: 30 percent Composition: 85 percent Geomorphic description: Geomorphic description: Tread on terrace • Mountaintop summit on mountain Slope: 2 to 15 percent • Mountaintop shoulder on mountain Elevation: 6,000 to 7,500 feet Slope: 30 to 60 percent Effective annual precipitation: 20 to 25 inches Elevation: 5,500 to 7,500 feet Frost-free period: 50 to 70 days Effective annual precipitation: 20 to 25 inches Surface layer texture: Cobbly loam Frost-free period: 50 to 70 days Rock fragments on the soil surface: 0.01 to 0.10 Surface layer texture: Very channery loam percent stones, 27 to 67 feet apart Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained Parent material: Gravelly glaciofluvial deposits Parent material: Residuum weathered from gabbro Native plant cover type: Rangeland Native plant cover type: Forestland Available water capacity: Mainly 9.0 inches Available water capacity: Mainly 1.3 inches Additional Components Additional Components Bridger and similar soils: 5 percent Cowood and similar soils: 3 percent Melville and similar soils: 5 percent Danaher and similar soils: 3 percent Redchief and similar soils: 5 percent Timberlin and similar soils: 2 percent Management Tongue River and similar soils: 2 percent For management information about this map unit, Management see appropriate sections in Part II of this publication. For management information about this map unit, see appropriate sections in Part II of this publication. 379F—Tongue River-Arrowpeak, moist complex, 15 to 60 percent slopes 381E—Duckcreek-Arrowpeak complex, Setting 8 to 45 percent slopes Field investigation intensity: Order 2 Setting Elevation: 5,500 to 7,500 feet Mean annual precipitation: 20 to 25 inches Field investigation intensity: Order 2 Frost-free period: 50 to 70 days Elevation: 6,000 to 7,500 feet Sweet Grass County Area, Montana—Part I 283

Mean annual precipitation: 20 to 25 inches Major Component Description Frost-free period: 50 to 70 days Fifer and similar soils Major Component Description Composition: 45 percent Geomorphic description: Duckcreek and similar soils • Mountaintop summit on mountain Composition: 60 percent • Mountaintop shoulder on mountain Geomorphic description: Mountainflank backslope on Slope: 15 to 45 percent mountain Elevation: 6,000 to 7,500 feet Slope: 8 to 45 percent Effective annual precipitation: 20 to 25 inches Elevation: 6,000 to 7,500 feet Frost-free period: 50 to 70 days Effective annual precipitation: 20 to 25 inches Surface layer texture: Loam Frost-free period: 50 to 70 days Depth to bedrock (paralithic): 10 to 20 inches Surface layer texture: Loam Drainage class: Well drained Depth to bedrock (paralithic): 20 to 40 inches Parent material: Loamy residuum weathered from Drainage class: Well drained sandstone and siltstone Parent material: Clayey residuum weathered from Native plant cover type: Rangeland sandstone and shale Available water capacity: Mainly 2.7 inches Native plant cover type: Rangeland Available water capacity: Mainly 6.0 inches Knep and similar soils Composition: 40 percent Arrowpeak and similar soils Geomorphic description: Composition: 30 percent • Mountainbase backslope on mountain Geomorphic description: • Mountainbase footslope on mountain • Mountaintop summit on mountain • Mountainflank backslope on mountain • Mountaintop shoulder on mountain Slope: 15 to 45 percent Slope: 8 to 45 percent Elevation: 6,000 to 7,500 feet Elevation: 6,000 to 7,500 feet Effective annual precipitation: 20 to 25 inches Effective annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Frost-free period: 50 to 70 days Surface layer texture: Channery loam Surface layer texture: Very channery loam Depth to bedrock (paralithic): 20 to 40 inches Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained Parent material: Loamy residuum weathered from Parent material: Residuum weathered from gabbro sandstone and siltstone Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 1.3 inches Available water capacity: Mainly 3.8 inches Additional Components Additional Components Cheadle and similar soils: 3 percent Doby and similar soils: 3 percent Cheadle and similar soils: 5 percent Bridger and similar soils: 2 percent Monaberg and similar soils: 5 percent Rock outcrop: 2 percent Tongue River and similar soils: 5 percent Management Management For management information about this map unit, For management information about this map unit, see appropriate sections in Part II of this publication. see appropriate sections in Part II of this publication.

382E—Fifer-Knep complex, 15 to 45 percent slopes 383D—Fifer-Rock outcrop complex, 4 to 15 percent slopes Setting Setting Elevation: 6,000 to 7,500 feet Mean annual precipitation: 20 to 25 inches Field investigation intensity: Order 2 Frost-free period: 50 to 70 days Elevation: 6,000 to 7,500 feet 284 Soil Survey

Mean annual precipitation: 20 to 25 inches Elevation: 6,000 to 7,500 feet Frost-free period: 50 to 70 days Effective annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Major Component Description Surface layer texture: Loam Fifer and similar soils Depth to bedrock (paralithic): 10 to 20 inches Composition: 45 percent Drainage class: Well drained Geomorphic description: Parent material: Loamy residuum weathered from • Mountaintop summit on mountain sandstone and shale • Mountaintop shoulder on mountain Native plant cover type: Rangeland Slope: 4 to 15 percent Available water capacity: Mainly 2.7 inches Elevation: 6,000 to 7,500 feet Effective annual precipitation: 20 to 25 inches Cheadle and similar soils Frost-free period: 50 to 70 days Composition: 40 percent Surface layer texture: Loam Geomorphic description: Depth to bedrock (paralithic): 10 to 20 inches • Mountaintop summit on mountain Drainage class: Well drained • Mountaintop shoulder on mountain Parent material: Loamy residuum weathered from Slope: 15 to 45 percent sandstone and siltstone Elevation: 6,000 to 7,500 feet Native plant cover type: Rangeland Effective annual precipitation: 20 to 25 inches Available water capacity: Mainly 2.7 inches Frost-free period: 50 to 70 days Surface layer texture: Channery loam Rock outcrop Depth to bedrock (lithic): 10 to 20 inches Composition: 40 percent Drainage class: Well drained Definition: Rock outcrop consists mainly of areas of Parent material: Residuum weathered from exposed hard bedrock. sandstone Geomorphic description: Mountain Native plant cover type: Rangeland Available water capacity: Mainly 1.1 inches Additional Components Additional Components Cheadle and similar soils: 5 percent Knep and similar soils: 5 percent Fifer and similar soils: 4 percent Tongue River and similar soils: 5 percent Knep and similar soils: 4 percent Tongue River and similar soils: 4 percent Management Rock outcrop: 3 percent For management information about this map unit, Management see appropriate sections in Part II of this publication. For management information about this map unit, see appropriate sections in Part II of this publication. 384E—Fifer-Cheadle complex, 15 to 45 percent slopes 385E—Millerlake-Arrowpeak-Adel Setting complex, 8 to 35 percent slopes Elevation: 6,000 to 7,500 feet Setting Mean annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Field investigation intensity: Order 2 Elevation: 6,000 to 7,500 feet Major Component Description Mean annual precipitation: 20 to 25 inches Fifer and similar soils Frost-free period: 50 to 70 days Composition: 45 percent Major Component Description Geomorphic description: • Mountaintop summit on mountain Millerlake and similar soils • Mountaintop shoulder on mountain Composition: 40 percent • Mountainflank shoulder on mountain Geomorphic description: Mountainbase toeslope on Slope: 15 to 45 percent mountain Sweet Grass County Area, Montana—Part I 285

Slope: 8 to 35 percent 386D—Millerlake loam, 4 to 15 percent Elevation: 6,000 to 7,500 feet slopes Effective annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Setting Surface layer texture: Loam Drainage class: Well drained Elevation: 6,000 to 7,500 feet Parent material: Loamy alluvium or colluvium Mean annual precipitation: 20 to 25 inches Native plant cover type: Rangeland Frost-free period: 50 to 70 days Available water capacity: Mainly 8.4 inches Major Component Description Arrowpeak and similar soils Millerlake and similar soils Composition: 25 percent Composition: 85 percent Geomorphic description: Geomorphic description: Fan • Mountaintop summit on mountain Slope: 4 to 15 percent • Mountaintop shoulder on mountain Elevation: 6,000 to 7,500 feet Slope: 15 to 35 percent Effective annual precipitation: 20 to 25 inches Elevation: 6,000 to 7,500 feet Frost-free period: 50 to 70 days Effective annual precipitation: 20 to 25 inches Surface layer texture: Loam Frost-free period: 50 to 70 days Drainage class: Well drained Surface layer texture: Very channery loam Parent material: Loamy alluvium or colluvium Depth to bedrock (lithic): 10 to 20 inches Native plant cover type: Rangeland Drainage class: Well drained Available water capacity: Mainly 8.4 inches Parent material: Residuum weathered from gabbro Additional Components Native plant cover type: Rangeland Available water capacity: Mainly 1.3 inches Adel and similar soils: 5 percent Bridger and similar soils: 5 percent Adel and similar soils Monaberg and similar soils: 5 percent Composition: 20 percent Management Geomorphic description: Mountain and swale Slope: 8 to 15 percent For management information about this map unit, Elevation: 6,000 to 7,500 feet see appropriate sections in Part II of this publication. Effective annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Surface layer texture: Loam 387E—Tongue River-Novary-Cowood Drainage class: Well drained complex, 4 to 45 percent slopes Parent material: Loamy alluvium or colluvium Native plant cover type: Rangeland Setting Available water capacity: Mainly 10.2 inches Elevation: 5,500 to 7,500 feet Mean annual precipitation: 20 to 25 inches Additional Components Frost-free period: 50 to 70 days Lymanson and similar soils: 4 percent Major Component Description Pintlar and similar soils: 4 percent Whitore and similar soils: 4 percent Tongue River and similar soils Adel and similar soils: 3 percent Composition: 50 percent Geomorphic description: Management • Mountainflank backslope on mountain For management information about this map unit, • Mountainflank footslope on mountain see appropriate sections in Part II of this publication. Slope: 15 to 45 percent 286 Soil Survey

Elevation: 5,500 to 7,500 feet 388D—Adel loam, 2 to 15 percent slopes Effective annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Setting Surface layer texture: Loam Depth to bedrock (paralithic): 20 to 40 inches Elevation: 6,000 to 7,500 feet Drainage class: Well drained Mean annual precipitation: 20 to 25 inches Parent material: Loamy residuum weathered from Frost-free period: 50 to 70 days sandstone and siltstone Major Component Description Native plant cover type: Forestland Available water capacity: Mainly 5.8 inches Adel and similar soils Composition: 85 percent Novary and similar soils Geomorphic description: Mountain and swale Composition: 20 percent Slope: 2 to 15 percent Geomorphic description: Drainageway and mountain Elevation: 6,000 to 7,500 feet Slope: 4 to 6 percent Effective annual precipitation: 20 to 25 inches Elevation: 5,500 to 7,500 feet Frost-free period: 50 to 70 days Effective annual precipitation: 20 to 25 inches Surface layer texture: Loam Frost-free period: 50 to 70 days Drainage class: Well drained Surface layer texture: Loam Parent material: Loamy alluvium or colluvium Drainage class: Poorly drained Native plant cover type: Rangeland Parent material: Loamy alluvium Available water capacity: Mainly 10.2 inches Native plant cover type: Rangeland Additional Components Flooding: Rare Water table: Present Bridger and similar soils: 5 percent Available water capacity: Mainly 9.5 inches Monaberg and similar soils: 5 percent Pintlar and similar soils: 5 percent Cowood and similar soils Management Composition: 15 percent Geomorphic description: For management information about this map unit, • Mountaintop summit on mountain see appropriate sections in Part II of this publication. • Mountaintop shoulder on mountain Slope: 15 to 45 percent Elevation: 5,500 to 7,500 feet 391F—Tongue River-Timberlin complex, Effective annual precipitation: 20 to 25 inches 35 to 60 percent slopes Frost-free period: 50 to 70 days Surface layer texture: Very channery loam Setting Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Elevation: 5,500 to 7,500 feet Parent material: Residuum weathered from Mean annual precipitation: 20 to 25 inches sandstone over gabbro Frost-free period: 50 to 70 days Native plant cover type: Forestland Major Component Description Available water capacity: Mainly 1.6 inches Tongue River and similar soils Additional Components Composition: 50 percent Arrowpeak and similar soils: 5 percent Geomorphic description: Danaher and similar soils: 5 percent • Mountainflank backslope on mountain Lymanson and similar soils: 5 percent • Mountainflank footslope on mountain Slope: 35 to 60 percent Management Elevation: 5,500 to 7,500 feet For management information about this map unit, Effective annual precipitation: 20 to 25 inches see appropriate sections in Part II of this publication. Frost-free period: 50 to 70 days Sweet Grass County Area, Montana—Part I 287

Surface layer texture: Loam Slope: 8 to 25 percent Depth to bedrock (paralithic): 20 to 40 inches Elevation: 4,200 to 6,000 feet Drainage class: Well drained Effective annual precipitation: 15 to 19 inches Parent material: Loamy residuum weathered from Frost-free period: 85 to 115 days sandstone and siltstone Surface layer texture: Loam Native plant cover type: Forestland Depth to bedrock (paralithic): 20 to 40 inches Available water capacity: Mainly 5.8 inches Drainage class: Well drained Parent material: Loamy residuum weathered from Timberlin and similar soils sandstone and siltstone Composition: 40 percent Native plant cover type: Rangeland Geomorphic description: Available water capacity: Mainly 4.6 inches • Mountainflank backslope on mountain • Mountainflank footslope on mountain Vershal and similar soils Slope: 35 to 60 percent Composition: 40 percent Elevation: 5,500 to 7,500 feet Geomorphic description: Effective annual precipitation: 20 to 25 inches • Nose slope summit on hill Frost-free period: 50 to 70 days • Nose slope shoulder on hill Surface layer texture: Gravelly loam • Knoll Depth to bedrock (lithic): 20 to 40 inches • Plain Drainage class: Well drained Slope: 8 to 35 percent Parent material: Loamy colluvium and/or residuum Elevation: 4,200 to 6,000 feet weathered from tuff breccia Effective annual precipitation: 15 to 19 inches Native plant cover type: Forestland Frost-free period: 85 to 115 days Available water capacity: Mainly 4.1 inches Surface layer texture: Very channery loam Depth to bedrock (lithic): 4 to 10 inches Additional Components Drainage class: Well drained Cowood and similar soils: 4 percent Parent material: Residuum weathered from Worock and similar soils: 4 percent sandstone Danaher and similar soils: 2 percent Native plant cover type: Rangeland Available water capacity: Mainly 0.6 inches Management For management information about this map unit, Additional Components see appropriate sections in Part II of this publication. Cabba and similar soils: 2 percent Castner and similar soils: 2 percent 392E—Doney-Vershal complex, Macar and similar soils: 2 percent 8 to 35 percent slopes Rock outcrop: 2 percent Sagedale and similar soils: 2 percent Setting Management Elevation: 4,200 to 6,000 feet For management information about this map unit, Mean annual precipitation: 15 to 19 inches see appropriate sections in Part II of this publication. Frost-free period: 85 to 115 days Major Component Description Doney and similar soils 393E—Vershal-Reedwest complex, Composition: 50 percent 8 to 35 percent slopes Geomorphic description: • Side slope backslope on hill Setting • Base slope backslope on hill • Base slope footslope on hill Elevation: 4,200 to 6,000 feet • Plain Mean annual precipitation: 15 to 19 inches • Swale Frost-free period: 85 to 115 days 288 Soil Survey

Major Component Description 394D—Whitlash-Beenom complex, Vershal and similar soils 4 to 15 percent slopes Composition: 50 percent Geomorphic description: Setting • Nose slope summit on hill • Nose slope shoulder on hill Elevation: 4,200 to 6,000 feet • Knoll Mean annual precipitation: 15 to 19 inches • Plain Frost-free period: 85 to 115 days Slope: 8 to 35 percent Elevation: 4,200 to 6,000 feet Major Component Description Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Whitlash and similar soils Surface layer texture: Very channery loam Composition: 50 percent Depth to bedrock (lithic): 4 to 10 inches Geomorphic description: Structural bench Drainage class: Well drained Slope: 8 to 15 percent Parent material: Residuum weathered from Elevation: 4,200 to 6,000 feet sandstone Effective annual precipitation: 15 to 19 inches Native plant cover type: Rangeland Frost-free period: 85 to 115 days Available water capacity: Mainly 0.6 inches Surface layer texture: Gravelly loam Depth to bedrock (lithic): 10 to 20 inches Reedwest and similar soils Drainage class: Well drained Composition: 35 percent Parent material: Residuum weathered from gabbro Geomorphic description: Native plant cover type: Rangeland • Side slope backslope on hill Available water capacity: Mainly 2.0 inches • Base slope backslope on hill • Base slope footslope on hill Beenom and similar soils • Plain Composition: 35 percent • Swale Geomorphic description: Structural bench Slope: 8 to 35 percent Slope: 4 to 15 percent Elevation: 4,200 to 6,000 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days Surface layer texture: Loam Surface layer texture: Gravelly loam Depth to bedrock (paralithic): 20 to 40 inches Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained Parent material: Loamy residuum weathered from Parent material: Residuum weathered from andesite sandstone and siltstone Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 2.8 inches Available water capacity: Mainly 4.6 inches Additional Components Additional Components Absarokee and similar soils: 3 percent Absarokee and similar soils: 4 percent Cabba and similar soils: 3 percent Pianohill and similar soils: 4 percent Castner and similar soils: 3 percent Rock outcrop: 4 percent Farnuf and similar soils: 3 percent Amherst and similar soils: 3 percent Rock outcrop: 3 percent Management Management For management information about this map unit, For management information about this map unit, see appropriate sections in Part II of this publication. see appropriate sections in Part II of this publication. Sweet Grass County Area, Montana—Part I 289

395E—Whitlash-Beenom-Bacbuster Elevation: 4,200 to 6,000 feet complex, 8 to 25 percent slopes Effective annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Surface layer texture: Clay loam Setting Depth to bedrock (paralithic): 20 to 40 inches Field investigation intensity: Order 2 Drainage class: Well drained Elevation: 4,200 to 6,000 feet Parent material: Clayey residuum weathered from Mean annual precipitation: 15 to 19 inches sandstone and shale Frost-free period: 85 to 115 days Native plant cover type: Rangeland Available water capacity: Mainly 5.0 inches Major Component Description Additional Components Whitlash and similar soils Amherst and similar soils: 4 percent Composition: 45 percent Castner and similar soils: 4 percent Geomorphic description: Pianohill and similar soils: 4 percent • Nose slope summit on hill Rock outcrop: 3 percent • Nose slope shoulder on hill Slope: 15 to 25 percent Management Elevation: 4,200 to 6,000 feet For management information about this map unit, Effective annual precipitation: 15 to 19 inches see appropriate sections in Part II of this publication. Frost-free period: 85 to 115 days Surface layer texture: Gravelly loam Depth to bedrock (lithic): 10 to 20 inches 396C—Soapcreek-Lallie family complex, Drainage class: Well drained 0 to 8 percent slopes Parent material: Residuum weathered from gabbro Native plant cover type: Rangeland Setting Available water capacity: Mainly 2.0 inches Elevation: 5,300 to 6,200 feet Beenom and similar soils Mean annual precipitation: 17 to 20 inches Composition: 25 percent Frost-free period: 70 to 90 days Geomorphic description: Major Component Description • Nose slope summit on hill • Nose slope backslope on hill Soapcreek and similar soils • Knoll Composition: 59 percent • Plain Geomorphic description: Flood-plain step Slope: 8 to 15 percent Slope: 0 to 4 percent Elevation: 4,200 to 6,000 feet Elevation: 5,300 to 6,200 feet Effective annual precipitation: 15 to 19 inches Effective annual precipitation: 17 to 20 inches Frost-free period: 85 to 115 days Frost-free period: 70 to 90 days Surface layer texture: Gravelly loam Surface layer texture: Clay loam Depth to bedrock (lithic): 10 to 20 inches Drainage class: Somewhat poorly drained Drainage class: Well drained Parent material: Clayey alluvium Parent material: Residuum weathered from andesite Native plant cover type: Rangeland Native plant cover type: Rangeland Flooding: Rare Available water capacity: Mainly 2.8 inches Water table: Present Available water capacity: Mainly 9.4 inches Bacbuster and similar soils Composition: 15 percent Lallie and similar soils Geomorphic description: Composition: 25 percent • Base slope backslope on hill Geomorphic description: Flood plain • Base slope footslope on hill Slope: 0 to 2 percent • Side slope backslope on hill Elevation: 5,300 to 6,200 feet • Plain Effective annual precipitation: 17 to 20 inches • Swale Frost-free period: 70 to 90 days Slope: 8 to 25 percent Surface layer texture: Silty clay 290 Soil Survey

Drainage class: Poorly drained Frost-free period: 70 to 90 days Parent material: Clayey alluvium Surface layer texture: Sandy loam Native plant cover type: Rangeland Drainage class: Well drained Flooding: Frequent Parent material: Loamy alluvium Water table: Present Native plant cover type: Rangeland Salt affected: Saline within 30 inches Available water capacity: Mainly 10.7 inches Available water capacity: Mainly 9.3 inches Bowery and similar soils Additional Components Composition: 20 percent Linwell and similar soils: 5 percent Geomorphic description: Hill and swale Fairway and similar soils: 4 percent Slope: 8 to 25 percent Macar and similar soils: 3 percent Elevation: 5,300 to 6,200 feet Doney and similar soils: 2 percent Effective annual precipitation: 17 to 20 inches Larry and similar soils: 2 percent Frost-free period: 70 to 90 days Surface layer texture: Loam Management Drainage class: Well drained For management information about this map unit, Parent material: Loamy alluvium or colluvium see appropriate sections in Part II of this publication. Native plant cover type: Rangeland Available water capacity: Mainly 10.6 inches 397E—Castner-Laceycreek-Bowery Additional Components complex, 8 to 25 percent slopes Work and similar soils: 5 percent Beenom and similar soils: 4 percent Setting Farnuf and similar soils: 4 percent Rock outcrop: 2 percent Elevation: 5,300 to 6,200 feet Mean annual precipitation: 17 to 20 inches Management Frost-free period: 70 to 90 days For management information about this map unit, Major Component Description see appropriate sections in Part II of this publication. Castner and similar soils Composition: 40 percent 397F—Castner-Laceycreek-Bowery Geomorphic description: complex, 25 to 60 percent slopes • Nose slope summit on hill • Nose slope shoulder on hill Setting Slope: 8 to 25 percent Elevation: 5,300 to 6,200 feet Elevation: 5,300 to 6,200 feet Effective annual precipitation: 17 to 20 inches Mean annual precipitation: 17 to 20 inches Frost-free period: 70 to 90 days Frost-free period: 70 to 90 days Surface layer texture: Channery loam Major Component Description Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Castner and similar soils Parent material: Residuum weathered from Composition: 40 percent sandstone Geomorphic description: Native plant cover type: Rangeland • Nose slope summit on escarpment Available water capacity: Mainly 1.4 inches • Nose slope shoulder on escarpment Slope: 25 to 60 percent Laceycreek and similar soils Elevation: 5,300 to 6,200 feet Composition: 25 percent Effective annual precipitation: 17 to 20 inches Geomorphic description: Hill and swale Frost-free period: 70 to 90 days Slope: 8 to 25 percent Surface layer texture: Channery loam Elevation: 5,300 to 6,200 feet Depth to bedrock (lithic): 10 to 20 inches Effective annual precipitation: 17 to 20 inches Drainage class: Well drained Sweet Grass County Area, Montana—Part I 291

Parent material: Residuum weathered from Major Component Description sandstone Cabba and similar soils Native plant cover type: Rangeland Composition: 85 percent Available water capacity: Mainly 1.4 inches Geomorphic description: • Nose slope backslope on escarpment Laceycreek and similar soils • Nose slope summit on escarpment Composition: 25 percent • Side slope backslope on escarpment Geomorphic description: Drainageway and Slope: 15 to 60 percent escarpment Elevation: 5,300 to 6,200 feet Slope: 25 to 45 percent Effective annual precipitation: 17 to 20 inches Elevation: 5,300 to 6,200 feet Frost-free period: 70 to 90 days Effective annual precipitation: 17 to 20 inches Surface layer texture: Very cobbly loam Frost-free period: 70 to 90 days Depth to bedrock (paralithic): 10 to 20 inches Surface layer texture: Sandy loam Drainage class: Well drained Drainage class: Well drained Parent material: Loamy residuum weathered from Parent material: Loamy alluvium sandstone and siltstone Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 10.7 inches Available water capacity: Mainly 1.7 inches Bowery and similar soils Additional Components Composition: 20 percent Geomorphic description: Head slope backslope on Castner and similar soils: 5 percent escarpment Doney and similar soils: 4 percent Slope: 25 to 45 percent Wayden and similar soils: 4 percent Elevation: 5,300 to 6,200 feet Rock outcrop: 2 percent Effective annual precipitation: 17 to 20 inches Frost-free period: 70 to 90 days Management Surface layer texture: Loam For management information about this map unit, Drainage class: Well drained see appropriate sections in Part II of this publication. Parent material: Loamy alluvium or colluvium Native plant cover type: Rangeland Available water capacity: Mainly 10.6 inches 399F—Reedwest-Cabba-Castner complex, Additional Components 15 to 60 percent slopes Beenom and similar soils: 4 percent Farnuf and similar soils: 4 percent Setting Work and similar soils: 4 percent Rock outcrop: 3 percent Elevation: 4,200 to 6,000 feet Mean annual precipitation: 15 to 19 inches Management Frost-free period: 85 to 115 days For management information about this map unit, Major Component Description see appropriate sections in Part II of this publication. Reedwest and similar soils Composition: 38 percent 398F—Cabba very cobbly loam, Geomorphic description: 15 to 60 percent slopes • Side slope backslope on escarpment • Base slope backslope on escarpment • Base slope footslope on escarpment Setting Slope: 15 to 60 percent Elevation: 5,300 to 6,200 feet Elevation: 4,200 to 6,000 feet Mean annual precipitation: 17 to 20 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 70 to 90 days Frost-free period: 85 to 115 days 292 Soil Survey

Surface layer texture: Loam 400D—Bowery-Nesda-Bonebasin Depth to bedrock (paralithic): 20 to 40 inches complex, 2 to 15 percent slopes Drainage class: Well drained Parent material: Loamy residuum weathered from Setting sandstone and siltstone Native plant cover type: Rangeland Elevation: 5,300 to 6,200 feet Available water capacity: Mainly 4.6 inches Mean annual precipitation: 17 to 20 inches Frost-free period: 70 to 90 days Cabba and similar soils Major Component Description Composition: 30 percent Geomorphic description: Bowery and similar soils • Nose slope backslope on escarpment Composition: 50 percent • Nose slope summit on escarpment Geomorphic description: Stream terrace • Side slope backslope on escarpment Slope: 2 to 15 percent Slope: 15 to 60 percent Elevation: 5,300 to 6,200 feet Elevation: 4,200 to 6,000 feet Effective annual precipitation: 17 to 20 inches Effective annual precipitation: 15 to 19 inches Frost-free period: 70 to 90 days Frost-free period: 85 to 115 days Surface layer texture: Loam Surface layer texture: Gravelly loam Drainage class: Well drained Depth to bedrock (paralithic): 10 to 20 inches Parent material: Loamy alluvium or colluvium Drainage class: Well drained Native plant cover type: Rangeland Parent material: Loamy residuum weathered from Available water capacity: Mainly 10.6 inches sandstone and siltstone Native plant cover type: Forestland Nesda and similar soils Available water capacity: Mainly 1.9 inches Composition: 25 percent Geomorphic description: Flood plain Castner and similar soils Slope: 2 to 4 percent Composition: 25 percent Elevation: 5,300 to 6,200 feet Geomorphic description: Effective annual precipitation: 17 to 20 inches • Nose slope summit on escarpment Frost-free period: 70 to 90 days • Nose slope shoulder on escarpment Surface layer texture: Gravelly loam Slope: 15 to 60 percent Drainage class: Well drained Elevation: 4,200 to 6,000 feet Parent material: Sandy and gravelly alluvium Effective annual precipitation: 15 to 19 inches Native plant cover type: Rangeland Frost-free period: 85 to 115 days Flooding: Occasional Surface layer texture: Gravelly loam Available water capacity: Mainly 3.5 inches Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Bonebasin and similar soils Parent material: Residuum weathered from Composition: 15 percent sandstone Geomorphic description: Flood plain Native plant cover type: Rangeland Slope: 2 to 4 percent Available water capacity: Mainly 1.4 inches Elevation: 5,300 to 6,200 feet Effective annual precipitation: 17 to 20 inches Additional Components Frost-free period: 70 to 90 days Bowery and similar soils: 3 percent Surface layer texture: Loam Farnuf and similar soils: 3 percent Drainage class: Very poorly drained Rock outcrop: 1 percent Parent material: Gravelly alluvium Native plant cover type: Rangeland Management Flooding: Occasional For management information about this map unit, Water table: Present see appropriate sections in Part II of this publication. Available water capacity: Mainly 5.9 inches Sweet Grass County Area, Montana—Part I 293

Additional Components Major Component Description Korchea and similar soils: 4 percent Reedwest and similar soils Breeton and similar soils: 3 percent Composition: 68 percent Meadowcreek and similar soils: 3 percent Geomorphic description: • Side slope backslope on escarpment Management • Base slope backslope on escarpment For management information about this map unit, • Base slope footslope on escarpment see appropriate sections in Part II of this publication. Slope: 15 to 60 percent Elevation: 3,900 to 6,000 feet Effective annual precipitation: 15 to 19 inches 401B—Roy cobbly loam, 0 to 4 percent Frost-free period: 85 to 115 days slopes Surface layer texture: Loam Rock fragments on the soil surface: 0.1 to 3.0 percent Setting stones, 3 to 27 feet apart Depth to bedrock (paralithic): 20 to 40 inches Elevation: 5,300 to 6,200 feet Drainage class: Well drained Mean annual precipitation: 17 to 20 inches Parent material: Loamy residuum weathered from Frost-free period: 70 to 90 days sandstone and siltstone Major Component Description Native plant cover type: Forestland Available water capacity: Mainly 4.6 inches Roy and similar soils Composition: 85 percent Rock outcrop Geomorphic description: Tread on terrace Composition: 20 percent Slope: 0 to 4 percent Definition: Rock outcrop consists mainly of areas of Elevation: 5,300 to 6,200 feet exposed hard bedrock. Effective annual precipitation: 17 to 20 inches Geomorphic description: Dike Frost-free period: 70 to 90 days Surface layer texture: Cobbly loam Additional Components Drainage class: Well drained Parent material: Gravelly glaciofluvial deposits Farnuf and similar soils: 4 percent Native plant cover type: Rangeland Cabba and similar soils: 3 percent Available water capacity: Mainly 4.5 inches Rubble land: 3 percent Additional Components Castner and similar soils: 2 percent Shawmut and similar soils: 5 percent Management Tamaneen and similar soils: 5 percent Work and similar soils: 5 percent For management information about this map unit, see appropriate sections in Part II of this publication. Management For management information about this map unit, see appropriate sections in Part II of this publication. 403F—Cabba-Castner-Rock outcrop complex, moist, 25 to 60 percent 402F—Reedwest-Rock outcrop complex, slopes 15 to 60 percent slopes, very stony Setting Setting Field investigation intensity: Order 2 Elevation: 3,900 to 6,000 feet Elevation: 3,900 to 6,000 feet Mean annual precipitation: 15 to 19 inches Mean annual precipitation: 15 to 19 inches Frost-free period: 85 to 115 days Frost-free period: 85 to 115 days 294 Soil Survey

Major Component Description 404F—Lymanson-Doby-Rock outcrop Cabba and similar soils complex, 15 to 60 percent slopes Composition: 40 percent Geomorphic description: Setting • Nose slope backslope on escarpment Elevation: 6,000 to 7,500 feet • Nose slope summit on escarpment Mean annual precipitation: 20 to 25 inches • Side slope backslope on escarpment Frost-free period: 50 to 70 days Slope: 25 to 60 percent Elevation: 3,900 to 6,000 feet Major Component Description Effective annual precipitation: 15 to 19 inches Lymanson and similar soils Frost-free period: 85 to 115 days Composition: 40 percent Surface layer texture: Loam Geomorphic description: Mountainflank backslope on Depth to bedrock (paralithic): 10 to 20 inches mountain Drainage class: Well drained Slope: 15 to 50 percent Parent material: Loamy residuum weathered from Elevation: 6,000 to 7,500 feet sandstone and siltstone Effective annual precipitation: 20 to 25 inches Native plant cover type: Forestland Frost-free period: 50 to 70 days Available water capacity: Mainly 2.0 inches Surface layer texture: Loam Depth to bedrock (paralithic): 20 to 40 inches Castner and similar soils Drainage class: Well drained Composition: 35 percent Parent material: Loamy residuum weathered from Geomorphic description: sandstone and siltstone • Nose slope shoulder on escarpment Native plant cover type: Rangeland • Nose slope summit on escarpment Available water capacity: Mainly 4.0 inches Slope: 25 to 60 percent Elevation: 3,900 to 6,000 feet Doby and similar soils Effective annual precipitation: 15 to 19 inches Composition: 30 percent Frost-free period: 85 to 115 days Geomorphic description: Surface layer texture: Channery loam • Mountaintop summit on mountain Depth to bedrock (lithic): 10 to 20 inches • Mountainflank backslope on mountain Drainage class: Well drained Slope: 15 to 60 percent Parent material: Residuum weathered from Elevation: 6,000 to 7,500 feet sandstone Effective annual precipitation: 20 to 25 inches Native plant cover type: Forestland Frost-free period: 50 to 70 days Available water capacity: Mainly 1.4 inches Surface layer texture: Stony clay loam Depth to bedrock (paralithic): 10 to 20 inches Rock outcrop Drainage class: Well drained Composition: 15 percent Parent material: Clayey residuum weathered from Definition: Rock outcrop consists mainly of areas of shale and siltstone exposed hard bedrock. Native plant cover type: Rangeland Geomorphic description: Escarpment Available water capacity: Mainly 2.3 inches Additional Components Rock outcrop Doney and similar soils: 4 percent Composition: 20 percent Wayden and similar soils: 3 percent Definition: Rock outcrop consists mainly of areas of Sagedale and similar soils: 2 percent exposed hard bedrock. Macar and similar soils: 1 percent Geomorphic description: Mountain Management Additional Components For management information about this map unit, Gilispie and similar soils: 4 percent see appropriate sections in Part II of this publication. Adel and similar soils: 2 percent Sweet Grass County Area, Montana—Part I 295

Cheadle and similar soils: 2 percent Rock outcrop Tongue River and similar soils: 2 percent Composition: 20 percent Definition: Rock outcrop consists mainly of areas of Management exposed hard bedrock. For management information about this map unit, Geomorphic description: Mountain see appropriate sections in Part II of this publication. Additional Components Lymanson and similar soils: 5 percent 405F—Tongue River-Doby-Rock outcrop Monaberg and similar soils: 5 percent complex, 15 to 60 percent slopes Management For management information about this map unit, Setting see appropriate sections in Part II of this publication. Elevation: 5,500 to 7,500 feet Mean annual precipitation: 20 to 25 inches 406E—Doney-Macar loams, Frost-free period: 50 to 70 days 4 to 25 percent slopes Major Component Description Setting Tongue River and similar soils Composition: 40 percent Elevation: 4,200 to 6,000 feet Geomorphic description: Mean annual precipitation: 15 to 19 inches • Mountainbase backslope on mountain Frost-free period: 85 to 115 days • Mountainbase footslope on mountain Major Component Description • Mountainflank backslope on mountain Slope: 15 to 60 percent Doney and similar soils Elevation: 5,500 to 7,500 feet Composition: 45 percent Effective annual precipitation: 20 to 25 inches Geomorphic description: Frost-free period: 50 to 70 days • Base slope backslope on hill Surface layer texture: Loam • Base slope footslope on hill Depth to bedrock (paralithic): 20 to 40 inches • Side slope backslope on hill Drainage class: Well drained • Plain Parent material: Loamy colluvium and/or residuum • Swale Native plant cover type: Forestland Slope: 4 to 25 percent Available water capacity: Mainly 5.8 inches Elevation: 4,200 to 6,000 feet Effective annual precipitation: 15 to 19 inches Doby and similar soils Frost-free period: 85 to 115 days Composition: 30 percent Surface layer texture: Loam Geomorphic description: Depth to bedrock (paralithic): 20 to 40 inches • Mountaintop summit on mountain Drainage class: Well drained • Mountainflank backslope on mountain Parent material: Loamy residuum weathered from Slope: 15 to 60 percent sandstone and siltstone Elevation: 5,500 to 7,500 feet Native plant cover type: Rangeland Effective annual precipitation: 20 to 25 inches Available water capacity: Mainly 4.6 inches Frost-free period: 50 to 70 days Surface layer texture: Stony clay loam Macar and similar soils Depth to bedrock (paralithic): 10 to 20 inches Composition: 40 percent Drainage class: Well drained Geomorphic description: Parent material: Clayey residuum weathered from • Base slope toeslope on hill shale and siltstone • Base slope footslope on hill Native plant cover type: Forestland • Plain Available water capacity: Mainly 2.3 inches • Swale 296 Soil Survey

Slope: 4 to 25 percent Frost-free period: 50 to 70 days Elevation: 4,200 to 6,000 feet Surface layer texture: Gravelly loam Effective annual precipitation: 15 to 19 inches Depth to bedrock (lithic): 20 to 40 inches Frost-free period: 85 to 115 days Drainage class: Well drained Surface layer texture: Loam Parent material: Loamy colluvium and/or residuum Drainage class: Well drained weathered from tuff breccia Parent material: Loamy alluvium Native plant cover type: Forestland Native plant cover type: Rangeland Available water capacity: Mainly 4.1 inches Available water capacity: Mainly 9.4 inches Additional Components Additional Components Cheadle and similar soils: 5 percent Cabba and similar soils: 4 percent Warwood and similar soils: 5 percent Amor and similar soils: 3 percent Arrowpeak and similar soils: 3 percent Sagedale and similar soils: 3 percent Rock outcrop: 2 percent Wayden and similar soils: 3 percent Management Castner and similar soils: 2 percent For management information about this map unit, Management see appropriate sections in Part II of this publication. For management information about this map unit, see appropriate sections in Part II of this publication. 408E—Warwood-Timberlin-Cowood complex, 8 to 35 percent slopes 407F—Danaher-Timberlin complex, 25 to 60 percent slopes Setting Elevation: 5,500 to 7,500 feet Setting Mean annual precipitation: 20 to 25 inches Elevation: 5,500 to 7,500 feet Frost-free period: 50 to 70 days Mean annual precipitation: 20 to 25 inches Major Component Description Frost-free period: 50 to 70 days Warwood and similar soils Major Component Description Composition: 40 percent Danaher and similar soils Geomorphic description: Mountainbase footslope on Composition: 50 percent mountain Geomorphic description: Slope: 15 to 35 percent • Mountainbase footslope on mountain Elevation: 5,500 to 7,500 feet • Mountainbase toeslope on mountain Effective annual precipitation: 20 to 25 inches Slope: 25 to 60 percent Frost-free period: 50 to 70 days Elevation: 5,500 to 7,500 feet Surface layer texture: Loam Effective annual precipitation: 20 to 25 inches Drainage class: Well drained Frost-free period: 50 to 70 days Parent material: Loamy alluvium or colluvium Surface layer texture: Loam Native plant cover type: Forestland Drainage class: Well drained Available water capacity: Mainly 9.3 inches Parent material: Silty and clayey colluvium or alluvium Native plant cover type: Forestland Timberlin and similar soils Available water capacity: Mainly 9.3 inches Composition: 30 percent Geomorphic description: Timberlin and similar soils • Mountainflank backslope on mountain Composition: 35 percent • Mountainflank footslope on mountain Geomorphic description: Slope: 8 to 35 percent • Mountainflank backslope on mountain Elevation: 5,500 to 7,500 feet • Mountainflank footslope on mountain Effective annual precipitation: 20 to 25 inches Slope: 25 to 60 percent Frost-free period: 50 to 70 days Elevation: 5,500 to 7,500 feet Surface layer texture: Gravelly loam Effective annual precipitation: 20 to 25 inches Depth to bedrock (lithic): 20 to 40 inches Sweet Grass County Area, Montana—Part I 297

Drainage class: Well drained Timberlin and similar soils Parent material: Loamy colluvium and/or residuum Composition: 30 percent weathered from tuff breccia Geomorphic description: Native plant cover type: Forestland • Mountainflank backslope on mountain Available water capacity: Mainly 4.1 inches • Mountainflank footslope on mountain Slope: 35 to 60 percent Cowood and similar soils Elevation: 5,500 to 7,500 feet Composition: 20 percent Effective annual precipitation: 20 to 25 inches Geomorphic description: Frost-free period: 50 to 70 days • Mountaintop summit on mountain Surface layer texture: Gravelly loam • Mountaintop shoulder on mountain Depth to bedrock (lithic): 20 to 40 inches Slope: 8 to 35 percent Drainage class: Well drained Elevation: 5,500 to 7,500 feet Parent material: Loamy colluvium and/or residuum Effective annual precipitation: 20 to 25 inches weathered from tuff breccia Frost-free period: 50 to 70 days Native plant cover type: Forestland Surface layer texture: Stony loam Available water capacity: Mainly 4.1 inches Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Cowood and similar soils Parent material: Residuum weathered from gabbro Composition: 20 percent Native plant cover type: Forestland Geomorphic description: Available water capacity: Mainly 1.8 inches • Mountaintop summit on mountain • Mountaintop shoulder on mountain Additional Components Slope: 35 to 60 percent Danaher and similar soils: 4 percent Elevation: 5,500 to 7,500 feet Arrowpeak and similar soils: 3 percent Effective annual precipitation: 20 to 25 inches Rock outcrop: 3 percent Frost-free period: 50 to 70 days Surface layer texture: Stony loam Management Depth to bedrock (lithic): 10 to 20 inches For management information about this map unit, Drainage class: Well drained see appropriate sections in Part II of this publication. Parent material: Residuum weathered from gabbro Native plant cover type: Forestland Available water capacity: Mainly 1.5 inches 408F—Warwood-Timberlin-Cowood complex, 35 to 60 percent slopes Additional Components

Setting Pintlar and similar soils: 4 percent Arrowpeak and similar soils: 2 percent Elevation: 5,500 to 7,500 feet Danaher and similar soils: 2 percent Mean annual precipitation: 20 to 25 inches Rock outcrop: 2 percent Frost-free period: 50 to 70 days Major Component Description Management Warwood and similar soils For management information about this map unit, Composition: 40 percent see appropriate sections in Part II of this publication. Geomorphic description: Mountainbase footslope on mountain Slope: 35 to 45 percent Elevation: 5,500 to 7,500 feet 409F—Merino-Elve-Rock outcrop Effective annual precipitation: 20 to 25 inches complex, 25 to 80 percent slopes Frost-free period: 50 to 70 days Surface layer texture: Loam Setting Drainage class: Well drained Parent material: Loamy alluvium or colluvium Elevation: 5,500 to 7,500 feet Native plant cover type: Forestland Mean annual precipitation: 20 to 25 inches Available water capacity: Mainly 9.3 inches Frost-free period: 50 to 70 days 298 Soil Survey

Major Component Description 410E—Adel-Timberlin complex, Merino and similar soils 8 to 35 percent slopes Composition: 45 percent Geomorphic description: Setting • Mountaintop summit on mountain Landscape: Mountains • Mountaintop shoulder on mountain Elevation: 5,500 to 7,500 feet Slope: 25 to 50 percent Mean annual precipitation: 20 to 25 inches Elevation: 5,500 to 7,500 feet Frost-free period: 50 to 70 days Effective annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Major Component Description Surface layer texture: Very gravelly sandy loam Adel and similar soils Depth to bedrock (lithic): 10 to 20 inches Composition: 60 percent Drainage class: Well drained Geomorphic description: Mountain and swale Parent material: Loamy residuum weathered from tuff Slope: 8 to 35 percent breccia Elevation: 5,500 to 7,500 feet Native plant cover type: Rangeland Effective annual precipitation: 20 to 25 inches Available water capacity: Mainly 1.0 inches Frost-free period: 50 to 70 days Surface layer texture: Loam Elve and similar soils Drainage class: Well drained Composition: 35 percent Parent material: Loamy alluvium or colluvium Geomorphic description: Native plant cover type: Forestland • Mountainbase footslope on mountain Available water capacity: Mainly 10.2 inches • Mountainbase backslope on mountain • Mountainflank backslope on mountain Timberlin and similar soils Slope: 25 to 80 percent Composition: 30 percent Elevation: 5,500 to 7,500 feet Geomorphic description: Effective annual precipitation: 20 to 25 inches • Mountainflank backslope on mountain Frost-free period: 50 to 70 days • Mountainflank footslope on mountain Surface layer texture: Very gravelly loam Slope: 15 to 35 percent Drainage class: Somewhat excessively drained Elevation: 5,500 to 7,500 feet Parent material: Loamy alluvium weathered from Effective annual precipitation: 20 to 25 inches volcanic breccia Frost-free period: 50 to 70 days Native plant cover type: Forestland Surface layer texture: Gravelly loam Available water capacity: Mainly 4.4 inches Depth to bedrock (lithic): 20 to 40 inches Drainage class: Well drained Rock outcrop Parent material: Loamy colluvium and/or residuum Composition: 15 percent weathered from tuff breccia Definition: Rock outcrop consists mainly of areas of Native plant cover type: Forestland exposed hard bedrock. Available water capacity: Mainly 4.1 inches Geomorphic description: Mountain Additional Components Additional Components Pintlar and similar soils: 5 percent Arrowpeak and similar soils: 3 percent Bridger and similar soils: 3 percent Monaberg and similar soils: 2 percent Warwood and similar soils: 2 percent Management Management For management information about this map unit, For management information about this map unit, see appropriate sections in Part II of this publication. see appropriate sections in Part II of this publication. Sweet Grass County Area, Montana—Part I 299

411E—Pianohill-Whitlash-Adel complex, Parent material: Loamy alluvium or colluvium 15 to 45 percent slopes Native plant cover type: Rangeland Available water capacity: Mainly 10.6 inches Setting Additional Components Field investigation intensity: Order 2 Beenom and similar soils: 5 percent Elevation: 5,300 to 6,200 feet Sawicki and similar soils: 5 percent Mean annual precipitation: 17 to 20 inches Weedzunit and similar soils: 5 percent Frost-free period: 70 to 90 days Management Major Component Description For management information about this map unit, see appropriate sections in Part II of this publication. Pianohill and similar soils Composition: 40 percent Geomorphic description: 412E—Lap-Winspect-Rock outcrop • Base slope footslope on hill complex, 8 to 35 percent slopes • Base slope backslope on hill • Side slope backslope on hill Setting Slope: 15 to 35 percent Elevation: 5,300 to 6,200 feet Elevation: 5,300 to 6,200 feet Effective annual precipitation: 17 to 20 inches Mean annual precipitation: 17 to 20 inches Frost-free period: 70 to 90 days Frost-free period: 70 to 90 days Surface layer texture: Loam Major Component Description Depth to bedrock (lithic): 20 to 40 inches Drainage class: Well drained Lap and similar soils Parent material: Residuum weathered from tuff Composition: 40 percent breccia Geomorphic description: Native plant cover type: Rangeland • Nose slope summit on hill Available water capacity: Mainly 5.2 inches • Nose slope shoulder on hill Slope: 8 to 35 percent Whitlash and similar soils Elevation: 5,300 to 6,200 feet Composition: 30 percent Effective annual precipitation: 17 to 20 inches Geomorphic description: Frost-free period: 70 to 90 days • Nose slope summit on hill Surface layer texture: Channery loam • Nose slope shoulder on hill Depth to bedrock (lithic): 10 to 20 inches Slope: 15 to 45 percent Drainage class: Well drained Elevation: 5,300 to 6,200 feet Parent material: Residuum weathered from limestone Effective annual precipitation: 17 to 20 inches Native plant cover type: Rangeland Frost-free period: 70 to 90 days Available water capacity: Mainly 1.5 inches Surface layer texture: Gravelly loam Depth to bedrock (lithic): 10 to 20 inches Winspect and similar soils Drainage class: Well drained Composition: 35 percent Parent material: Residuum weathered from gabbro Geomorphic description: Native plant cover type: Rangeland • Base slope backslope on hill Available water capacity: Mainly 2.0 inches • Base slope footslope on hill Slope: 8 to 35 percent Bowery and similar soils Elevation: 5,300 to 6,200 feet Composition: 15 percent Effective annual precipitation: 17 to 20 inches Geomorphic description: Hill and swale Frost-free period: 70 to 90 days Slope: 2 to 15 percent Surface layer texture: Cobbly loam Elevation: 5,300 to 6,200 feet Drainage class: Well drained Effective annual precipitation: 17 to 20 inches Parent material: Gravelly colluvium weathered from Frost-free period: 70 to 90 days limestone Surface layer texture: Loam Native plant cover type: Rangeland Drainage class: Well drained Available water capacity: Mainly 6.5 inches 300 Soil Survey

Rock outcrop Parent material: Gravelly colluvium weathered from Composition: 15 percent limestone Definition: Rock outcrop consists mainly of areas of Native plant cover type: Rangeland exposed hard bedrock. Available water capacity: Mainly 6.5 inches Geomorphic description: Hill Additional Components Additional Components Bowery and similar soils: 10 percent Bowery and similar soils: 10 percent Rock outcrop: 10 percent Management Management For management information about this map unit, For management information about this map unit, see appropriate sections in Part II of this publication. see appropriate sections in Part II of this publication.

412F—Lap-Winspect complex, 413E—Cabba-Bowery complex, 35 to 70 percent slopes 2 to 60 percent slopes Setting Setting Elevation: 5,300 to 6,200 feet Elevation: 5,300 to 6,200 feet Mean annual precipitation: 17 to 20 inches Mean annual precipitation: 17 to 20 inches Frost-free period: 70 to 90 days Frost-free period: 70 to 90 days Major Component Description Major Component Description Cabba and similar soils Composition: 60 percent Lap and similar soils Geomorphic description: Composition: 45 percent • Nose slope summit on hill Geomorphic description: • Nose slope backslope on hill • Mountaintop summit on mountain • Side slope backslope on hill • Mountaintop shoulder on mountain Slope: 15 to 60 percent Slope: 35 to 70 percent Elevation: 5,300 to 6,200 feet Elevation: 5,300 to 6,200 feet Effective annual precipitation: 17 to 20 inches Effective annual precipitation: 17 to 20 inches Frost-free period: 70 to 90 days Frost-free period: 70 to 90 days Surface layer texture: Gravelly loam Surface layer texture: Channery loam Depth to bedrock (paralithic): 10 to 20 inches Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained Parent material: Loamy residuum weathered from Parent material: Residuum weathered from limestone sandstone and siltstone Native plant cover type: Forestland Native plant cover type: Rangeland Available water capacity: Mainly 1.5 inches Available water capacity: Mainly 2.4 inches

Winspect and similar soils Bowery and similar soils Composition: 35 percent Composition: 25 percent Geomorphic description: Geomorphic description: Hill and swale • Mountainbase footslope on mountain Slope: 2 to 15 percent • Mountainbase toeslope on mountain Elevation: 5,300 to 6,200 feet • Mountainflank backslope on mountain Effective annual precipitation: 17 to 20 inches Slope: 35 to 70 percent Frost-free period: 70 to 90 days Elevation: 5,300 to 6,200 feet Surface layer texture: Loam Effective annual precipitation: 17 to 20 inches Drainage class: Well drained Frost-free period: 70 to 90 days Parent material: Loamy alluvium or colluvium Surface layer texture: Cobbly loam Native plant cover type: Rangeland Drainage class: Well drained Available water capacity: Mainly 10.6 inches Sweet Grass County Area, Montana—Part I 301

Additional Components Additional Components Castner and similar soils: 4 percent Millerlake and similar soils: 5 percent Doney and similar soils: 4 percent Monaberg and similar soils: 5 percent Sweetweed and similar soils: 4 percent Redchief and similar soils: 5 percent Rock outcrop: 3 percent Management Management For management information about this map unit, For management information about this map unit, see appropriate sections in Part II of this publication. see appropriate sections in Part II of this publication.

414D—Libeg, extremely bouldery-Adel 414F—Libeg-Libeg, extremely bouldery- complex, 4 to 15 percent slopes Adel complex, 15 to 60 percent slopes

Setting Setting Elevation: 5,500 to 7,500 feet Elevation: 5,500 to 7,500 feet Mean annual precipitation: 20 to 25 inches Mean annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Frost-free period: 50 to 70 days Major Component Description Major Component Description Libeg and similar soils Composition: 50 percent Libeg and similar soils Geomorphic description: Composition: 35 percent • Mountainbase footslope on mountain Geomorphic description: • Mountainbase backslope on mountain • Mountainflank backslope on mountain • Mountainflank backslope on mountain • Mountainbase footslope on mountain Slope: 4 to 15 percent Slope: 15 to 60 percent Elevation: 5,500 to 7,500 feet Elevation: 5,500 to 7,500 feet Effective annual precipitation: 20 to 25 inches Effective annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Frost-free period: 50 to 70 days Surface layer texture: Very cobbly loam Surface layer texture: Very cobbly sandy loam Rock fragments on the soil surface: 3 to 15 percent Rock fragments on the soil surface: 3 to 15 percent boulders, 3 to 20 feet apart boulders, 3 to 20 feet apart Drainage class: Well drained Drainage class: Well drained Parent material: Gravelly till Parent material: Gravelly till Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 4.0 inches Available water capacity: Mainly 4.3 inches

Adel and similar soils Adel and similar soils Composition: 35 percent Composition: 25 percent Geomorphic description: Mountain and swale Geomorphic description: Mountain and swale Slope: 4 to 15 percent Slope: 15 to 35 percent Elevation: 5,500 to 7,500 feet Elevation: 5,500 to 7,500 feet Effective annual precipitation: 20 to 25 inches Effective annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Frost-free period: 50 to 70 days Surface layer texture: Loam Surface layer texture: Loam Drainage class: Well drained Drainage class: Well drained Parent material: Loamy alluvium or colluvium Parent material: Loamy alluvium or colluvium Native plant cover type: Forestland Native plant cover type: Forestland Available water capacity: Mainly 10.2 inches Available water capacity: Mainly 10.2 inches 302 Soil Survey

Libeg and similar soils Adel and similar soils Composition: 15 percent Composition: 25 percent Geomorphic description: Geomorphic description: Mountain and swale • Mountainflank backslope on mountain Slope: 15 to 35 percent • Mountainbase footslope on mountain Elevation: 5,500 to 7,500 feet Slope: 15 to 60 percent Effective annual precipitation: 20 to 25 inches Elevation: 5,500 to 7,500 feet Frost-free period: 50 to 70 days Effective annual precipitation: 20 to 25 inches Surface layer texture: Loam Frost-free period: 50 to 70 days Drainage class: Well drained Surface layer texture: Very cobbly sandy loam Parent material: Loamy alluvium or colluvium Drainage class: Well drained Native plant cover type: Forestland Parent material: Gravelly till Available water capacity: Mainly 10.2 inches Native plant cover type: Rangeland Additional Components Available water capacity: Mainly 3.8 inches Bridger and similar soils: 5 percent Additional Components Libeg and similar soils: 5 percent Monaberg and similar soils: 8 percent Monaberg and similar soils: 5 percent Redchief and similar soils: 7 percent Management Bridger and similar soils: 5 percent Millerlake and similar soils: 5 percent For management information about this map unit, see appropriate sections in Part II of this publication. Management For management information about this map unit, see appropriate sections in Part II of this publication. 416C—Bearmouth, moist-Beehive complex, 2 to 8 percent slopes, extremely stony 415F—Rocko-Adel complex, 15 to 45 percent slopes Setting Elevation: 5,500 to 7,500 feet Setting Mean annual precipitation: 20 to 25 inches Elevation: 5,500 to 7,500 feet Frost-free period: 50 to 70 days Mean annual precipitation: 20 to 25 inches Major Component Description Frost-free period: 50 to 70 days Bearmouth and similar soils Major Component Description Composition: 50 percent Rocko and similar soils Geomorphic description: Stream terrace Composition: 60 percent Slope: 2 to 8 percent Geomorphic description: Mountainflank backslope on Elevation: 5,500 to 7,500 feet mountain Effective annual precipitation: 20 to 25 inches Slope: 15 to 45 percent Frost-free period: 50 to 70 days Elevation: 5,500 to 7,500 feet Surface layer texture: Very cobbly loam Effective annual precipitation: 20 to 25 inches Rock fragments on the soil surface: 3 to 15 percent Frost-free period: 50 to 70 days stones, 2 to 3 feet apart Surface layer texture: Cobbly loam Drainage class: Well drained Rock fragments on the soil surface: 0.1 to 3.0 percent Parent material: Sandy and gravelly alluvium stones Native plant cover type: Forestland Drainage class: Well drained Available water capacity: Mainly 2.9 inches Parent material: Gravelly colluvium weathered from sandstone and gravelly colluvium Beehive and similar soils Native plant cover type: Forestland Composition: 35 percent Available water capacity: Mainly 6.7 inches Geomorphic description: Flood plain Sweet Grass County Area, Montana—Part I 303

Slope: 2 to 8 percent 418D—Melville cobbly loam, 4 to 15 Elevation: 5,500 to 7,500 feet percent slopes Effective annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Setting Surface layer texture: Gravelly sandy loam Rock fragments on the soil surface: 3 to 15 percent Elevation: 6,000 to 7,500 feet stones, 2 to 3 feet apart Mean annual precipitation: 20 to 25 inches Drainage class: Somewhat poorly drained Frost-free period: 50 to 70 days Parent material: Sandy and gravelly alluvium Major Component Description Native plant cover type: Forestland Flooding: Frequent Melville and similar soils Water table: Present Composition: 85 percent Available water capacity: Mainly 2.6 inches Geomorphic description: Tread on terrace Slope: 4 to 15 percent Additional Components Elevation: 6,000 to 7,500 feet Novary and similar soils: 8 percent Effective annual precipitation: 20 to 25 inches Libeg and similar soils: 7 percent Frost-free period: 50 to 70 days Surface layer texture: Cobbly loam Management Drainage class: Well drained For management information about this map unit, Parent material: Gravelly glaciofluvial deposits see appropriate sections in Part II of this publication. Native plant cover type: Forestland Available water capacity: Mainly 9.0 inches 417B—Melville cobbly loam, Additional Components 0 to 4 percent slopes Redchief and similar soils: 8 percent Bridger and similar soils: 7 percent Setting Management Elevation: 5,500 to 7,500 feet For management information about this map unit, Mean annual precipitation: 20 to 25 inches see appropriate sections in Part II of this publication. Frost-free period: 50 to 70 days Major Component Description Melville and similar soils 419E—Winspect-Work-Bowery, 8 to 35 Composition: 85 percent percent slopes, extremely bouldery Geomorphic description: Tread on terrace Slope: 0 to 4 percent Setting Elevation: 5,500 to 7,500 feet Effective annual precipitation: 20 to 25 inches Elevation: 5,300 to 6,200 feet Frost-free period: 50 to 70 days Mean annual precipitation: 17 to 20 inches Surface layer texture: Cobbly loam Frost-free period: 70 to 90 days Drainage class: Well drained Major Component Description Parent material: Gravelly glaciofluvial deposits Native plant cover type: Forestland Winspect and similar soils Available water capacity: Mainly 9.0 inches Composition: 35 percent Geomorphic description: Additional Components • Nose slope summit on moraine Redchief and similar soils: 8 percent • Nose slope shoulder on moraine Bridger and similar soils: 7 percent Slope: 8 to 35 percent Elevation: 5,300 to 6,200 feet Management Effective annual precipitation: 17 to 20 inches For management information about this map unit, Frost-free period: 70 to 90 days see appropriate sections in Part II of this publication. Surface layer texture: Cobbly loam 304 Soil Survey

Rock fragments on the soil surface: 3 to 15 percent 420E—Tibson, extremely bouldery- boulders, 3 to 20 feet apart Bridger, extremely bouldery-Adel Drainage class: Well drained complex, 8 to 35 percent slopes Parent material: Gravelly glaciofluvial deposits weathered from limestone and sandstone Setting Native plant cover type: Rangeland Available water capacity: Mainly 6.5 inches Elevation: 6,000 to 7,500 feet Mean annual precipitation: 20 to 25 inches Work and similar soils Frost-free period: 50 to 70 days Composition: 35 percent Geomorphic description: Major Component Description • Base slope toeslope on moraine • Base slope footslope on moraine Bridger and similar soils Slope: 8 to 35 percent Composition: 39 percent Elevation: 5,300 to 6,200 feet Geomorphic description: Base slope footslope on Effective annual precipitation: 17 to 20 inches moraine Frost-free period: 70 to 90 days Slope: 8 to 35 percent Surface layer texture: Gravelly loam Elevation: 6,000 to 7,500 feet Rock fragments on the soil surface: 3 to 15 percent Effective annual precipitation: 20 to 25 inches boulders, 3 to 20 feet apart Frost-free period: 50 to 70 days Drainage class: Well drained Surface layer texture: Cobbly clay loam Parent material: Clayey alluvium Rock fragments on the soil surface: 3 to 15 percent Native plant cover type: Rangeland boulders, 3 to 20 feet apart Available water capacity: Mainly 8.3 inches Drainage class: Well drained Parent material: Silty and clayey alluvium Bowery and similar soils Native plant cover type: Rangeland Composition: 20 percent Available water capacity: Mainly 7.7 inches Geomorphic description: Moraine and swale Slope: 8 to 35 percent Tibson and similar soils Elevation: 5,300 to 6,200 feet Composition: 35 percent Effective annual precipitation: 17 to 20 inches Geomorphic description: Frost-free period: 70 to 90 days • Nose slope summit on moraine Surface layer texture: Loam • Nose slope shoulder on moraine Drainage class: Well drained • Side slope shoulder on moraine Parent material: Loamy alluvium or colluvium Slope: 8 to 35 percent Native plant cover type: Rangeland Elevation: 6,000 to 7,500 feet Available water capacity: Mainly 10.6 inches Effective annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Additional Components Surface layer texture: Gravelly loam Farnuf and similar soils: 5 percent Rock fragments on the soil surface: 3 to 15 percent Work and similar soils: 5 percent boulders, 3 to 20 feet apart Drainage class: Well drained Management Parent material: Gravelly till, unspecified For management information about this map unit, Native plant cover type: Rangeland see appropriate sections in Part II of this publication. Available water capacity: Mainly 5.1 inches Sweet Grass County Area, Montana—Part I 305

Adel and similar soils Elevation: 5,300 to 6,200 feet Composition: 20 percent Effective annual precipitation: 17 to 20 inches Geomorphic description: Moraine and swale Frost-free period: 70 to 90 days Slope: 8 to 35 percent Surface layer texture: Loam Elevation: 6,000 to 7,500 feet Drainage class: Well drained Effective annual precipitation: 20 to 25 inches Parent material: Loamy alluvium or colluvium Frost-free period: 50 to 70 days Native plant cover type: Rangeland Surface layer texture: Loam Available water capacity: Mainly 10.6 inches Drainage class: Well drained Additional Components Parent material: Loamy alluvium or colluvium Native plant cover type: Rangeland Laceycreek and similar soils: 5 percent Available water capacity: Mainly 10.2 inches Perma and similar soils: 5 percent Additional Components Management Whitore and similar soils: 6 percent For management information about this map unit, see appropriate sections in Part II of this publication. Management For management information about this map unit, see appropriate sections in Part II of this publication. 422C—Work, stony-Bowery complex, 2 to 8 percent slopes

421E—Sawicki, extremely bouldery- Setting Bowery complex, 4 to 25 percent Elevation: 5,300 to 6,200 feet slopes Mean annual precipitation: 17 to 20 inches Frost-free period: 70 to 90 days Setting Major Component Description Field investigation intensity: Order 2 Work and similar soils Elevation: 5,300 to 6,200 feet Composition: 72 percent Mean annual precipitation: 17 to 20 inches Geomorphic description: Fan Frost-free period: 70 to 90 days Slope: 2 to 8 percent Elevation: 5,300 to 6,200 feet Major Component Description Effective annual precipitation: 17 to 20 inches Sawicki and similar soils Frost-free period: 70 to 90 days Composition: 50 percent Surface layer texture: Stony loam Geomorphic description: Rock fragments on the soil surface: 0.01 to 0.10 • Side slope footslope on hill percent stones, 27 to 67 feet apart • Side slope backslope on hill Drainage class: Well drained Slope: 4 to 25 percent Parent material: Clayey alluvium Elevation: 5,300 to 6,200 feet Native plant cover type: Rangeland Effective annual precipitation: 17 to 20 inches Available water capacity: Mainly 8.3 inches Frost-free period: 70 to 90 days Surface layer texture: Very gravelly loam Bowery and similar soils Rock fragments on the soil surface: 3 to 15 percent Composition: 20 percent boulders, 3 to 20 feet apart Geomorphic description: Fan Drainage class: Well drained Slope: 2 to 8 percent Parent material: Gravelly till Elevation: 5,300 to 6,200 feet Native plant cover type: Rangeland Effective annual precipitation: 17 to 20 inches Available water capacity: Mainly 4.2 inches Frost-free period: 70 to 90 days Surface layer texture: Loam Bowery and similar soils Drainage class: Well drained Composition: 40 percent Parent material: Loamy alluvium or colluvium Geomorphic description: Hill and swale Native plant cover type: Rangeland Slope: 4 to 15 percent Available water capacity: Mainly 10.6 inches 306 Soil Survey

Additional Components Management Farnuf and similar soils: 3 percent For management information about this map unit, Winspect and similar soils: 3 percent see appropriate sections in Part II of this publication. Danvers and similar soils: 2 percent Management 424C—Bridger, very stony-Adel complex, For management information about this map unit, 2 to 8 percent slopes see appropriate sections in Part II of this publication. Setting Elevation: 6,000 to 7,500 feet 422E—Work, very stony-Bowery complex, Mean annual precipitation: 20 to 25 inches 8 to 35 percent slopes Frost-free period: 50 to 70 days Major Component Description Setting Bridger and similar soils Elevation: 5,300 to 6,200 feet Composition: 70 percent Mean annual precipitation: 17 to 20 inches Geomorphic description: Mountainbase on mountain Frost-free period: 70 to 90 days Slope: 2 to 8 percent Elevation: 6,000 to 7,500 feet Major Component Description Effective annual precipitation: 20 to 25 inches Work and similar soils Frost-free period: 50 to 70 days Composition: 65 percent Surface layer texture: Stony loam Geomorphic description: Fan Rock fragments on the soil surface: 0.1 to 3.0 percent Slope: 8 to 35 percent stones, 3 to 27 feet apart Elevation: 5,300 to 6,200 feet Drainage class: Well drained Effective annual precipitation: 17 to 20 inches Parent material: Silty and clayey alluvium Frost-free period: 70 to 90 days Native plant cover type: Rangeland Surface layer texture: Gravelly loam Available water capacity: Mainly 7.9 inches Rock fragments on the soil surface: 0.1 to 3.0 percent Note: This soil exists on the lower one third of the stones, 3 to 27 feet apart landform. Drainage class: Well drained Parent material: Clayey alluvium Adel and similar soils Native plant cover type: Rangeland Composition: 20 percent Available water capacity: Mainly 8.3 inches Geomorphic description: • Mountainbase on mountain Bowery and similar soils • Swale Composition: 25 percent Slope: 2 to 8 percent Geomorphic description: Fan Elevation: 6,000 to 7,500 feet Slope: 8 to 35 percent Effective annual precipitation: 20 to 25 inches Elevation: 5,300 to 6,200 feet Frost-free period: 50 to 70 days Effective annual precipitation: 17 to 20 inches Surface layer texture: Loam Frost-free period: 70 to 90 days Drainage class: Well drained Surface layer texture: Loam Parent material: Loamy alluvium or colluvium Drainage class: Well drained Native plant cover type: Rangeland Parent material: Loamy alluvium or colluvium Available water capacity: Mainly 10.2 inches Native plant cover type: Rangeland Additional Components Available water capacity: Mainly 10.6 inches Redchief and similar soils: 4 percent Additional Components Note: This soil exists on the middle one third of the Farnuf and similar soils: 3 percent landform. Winspect and similar soils: 3 percent Cheadle and similar soils: 2 percent Danvers and similar soils: 2 percent Note: This soil exists on the upper one third of the Wayden and similar soils: 2 percent landform. Sweet Grass County Area, Montana—Part I 307

Millerlake and similar soils: 2 percent Additional Components Note: This soil exists on the lower one third of the Millerlake and similar soils: 3 percent landform. Note: This soil exists on the lower one third of the Tibson and similar soils: 2 percent landform. Note: This soil exists on the middle one third of the Pintlar and similar soils: 3 percent landform. Cheadle and similar soils: 2 percent Management Note: This soil exists on the upper one third of the landform. For management information about this map unit, Redchief and similar soils: 2 percent see appropriate sections in Part II of this publication. Note: This soil exists on the middle one third of the landform. 424E—Bridger, very stony-Adel complex, Management 8 to 35 percent slopes For management information about this map unit, see appropriate sections in Part II of this publication. Setting Elevation: 6,000 to 7,500 feet Mean annual precipitation: 20 to 25 inches 425E—Pintlar-Bridger loams, Frost-free period: 50 to 70 days 4 to 35 percent slopes Major Component Description Setting Bridger and similar soils Composition: 60 percent Elevation: 5,500 to 7,500 feet Geomorphic description: Mountainbase on mountain Mean annual precipitation: 20 to 25 inches Slope: 8 to 35 percent Frost-free period: 50 to 70 days Elevation: 6,000 to 7,500 feet Major Component Description Effective annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Pintlar and similar soils Surface layer texture: Stony loam Composition: 45 percent Rock fragments on the soil surface: 0.1 to 3.0 percent Geomorphic description: Mountainflank on mountain stones, 3 to 27 feet apart and swale Drainage class: Well drained Slope: 4 to 35 percent Parent material: Silty and clayey alluvium Elevation: 5,500 to 7,500 feet Native plant cover type: Rangeland Effective annual precipitation: 20 to 25 inches Available water capacity: Mainly 7.9 inches Frost-free period: 50 to 70 days Note: This soil exists on the lower one third of the Surface layer texture: Loam landform. Drainage class: Well drained Parent material: Loamy alluvium Adel and similar soils Native plant cover type: Forestland Composition: 30 percent Available water capacity: Mainly 8.3 inches Geomorphic description: Mountainbase on mountain and swale Bridger and similar soils Slope: 8 to 35 percent Composition: 40 percent Elevation: 6,000 to 7,500 feet Geomorphic description: Mountainflank backslope on Effective annual precipitation: 20 to 25 inches mountain Frost-free period: 50 to 70 days Slope: 4 to 35 percent Surface layer texture: Loam Elevation: 5,500 to 7,500 feet Drainage class: Well drained Effective annual precipitation: 20 to 25 inches Parent material: Loamy alluvium or colluvium Frost-free period: 50 to 70 days Native plant cover type: Rangeland Surface layer texture: Loam Available water capacity: Mainly 10.2 inches Drainage class: Well drained 308 Soil Survey

Parent material: Silty and clayey alluvium Rock fragments on the soil surface: 0.1 to 3.0 percent Native plant cover type: Forestland stones, 3 to 27 feet apart Available water capacity: Mainly 8.2 inches Drainage class: Well drained Parent material: Gravelly colluvium Additional Components Native plant cover type: Forestland Adel and similar soils: 5 percent Available water capacity: Mainly 5.8 inches Monaberg and similar soils: 5 percent Additional Components Redchief and similar soils: 5 percent Danaher and similar soils: 5 percent Management Elve and similar soils: 5 percent For management information about this map unit, Timberlin and similar soils: 5 percent see appropriate sections in Part II of this publication. Management For management information about this map unit, 426F—Stemple-Worock complex, see appropriate sections in Part II of this publication. 35 to 70 percent slopes, very stony 428F—Tibson-Whitore-Rock outcrop Setting complex, 35 to 70 percent slopes Field investigation intensity: Order 2 Setting Elevation: 5,500 to 7,500 feet Mean annual precipitation: 20 to 25 inches Elevation: 6,000 to 7,500 feet Frost-free period: 50 to 70 days Mean annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Major Component Description Major Component Description Stemple and similar soils Tibson and similar soils Composition: 70 percent Composition: 40 percent Geomorphic description: Geomorphic description: Mountainflank backslope on • Mountainflank backslope on mountain mountain • Mountainflank footslope on mountain Slope: 35 to 70 percent Slope: 35 to 70 percent Elevation: 6,000 to 7,500 feet Elevation: 5,500 to 7,500 feet Effective annual precipitation: 20 to 25 inches Effective annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Frost-free period: 50 to 70 days Surface layer texture: Gravelly loam Surface layer texture: Very cobbly loam Drainage class: Well drained Rock fragments on the soil surface: 0.1 to 3.0 percent Parent material: Gravelly till, unspecified stones, 3 to 27 feet apart Native plant cover type: Forestland Drainage class: Well drained Available water capacity: Mainly 5.1 inches Parent material: Gravelly colluvium Native plant cover type: Forestland Whitore and similar soils Available water capacity: Mainly 4.0 inches Composition: 35 percent Geomorphic description: Mountainflank backslope on Worock and similar soils mountain Composition: 15 percent Slope: 35 to 60 percent Geomorphic description: Elevation: 6,000 to 7,500 feet • Mountainflank backslope on mountain Effective annual precipitation: 20 to 25 inches • Mountainflank footslope on mountain Frost-free period: 50 to 70 days Slope: 35 to 60 percent Surface layer texture: Loam Elevation: 5,500 to 7,500 feet Drainage class: Well drained Effective annual precipitation: 20 to 25 inches Parent material: Gravelly till Frost-free period: 50 to 70 days Native plant cover type: Forestland Surface layer texture: Gravelly loam Available water capacity: Mainly 5.0 inches Sweet Grass County Area, Montana—Part I 309

Rock outcrop Bigsag and similar soils Composition: 15 percent Composition: 15 percent Definition: Rock outcrop consists mainly of areas of Geomorphic description: Pothole on landslide and exposed hard bedrock. swale on landslide Geomorphic description: Mountain Slope: 2 to 4 percent Elevation: 5,300 to 6,200 feet Additional Components Effective annual precipitation: 17 to 20 inches Whitore and similar soils: 6 percent Frost-free period: 70 to 90 days Cheadle and similar soils: 4 percent Surface layer texture: Clay Drainage class: Very poorly drained Management Parent material: Clayey colluvium weathered from For management information about this map unit, sandstone and shale see appropriate sections in Part II of this publication. Native plant cover type: Rangeland Water table: Present Ponding duration: Long 429E—Work-Roy, bouldery-Bigsag family Salt affected: Saline within 30 inches complex, 2 to 35 percent slopes Available water capacity: Mainly 7.8 inches Additional Components Setting Bowery and similar soils: 4 percent Elevation: 5,300 to 6,200 feet Perma and similar soils: 3 percent Mean annual precipitation: 17 to 20 inches Shambo and similar soils: 3 percent Frost-free period: 70 to 90 days Winspect and similar soils: 3 percent Major Component Description Management Work and similar soils For management information about this map unit, Composition: 42 percent see appropriate sections in Part II of this publication. Geomorphic description: Landslide Slope: 8 to 35 percent Elevation: 5,300 to 6,200 feet Effective annual precipitation: 17 to 20 inches 430E—Mowbray-Bridger-Novary complex, Frost-free period: 70 to 90 days 0 to 35 percent slopes Surface layer texture: Stony clay loam Drainage class: Well drained Setting Parent material: Clayey colluvium weathered from sandstone and shale Elevation: 6,000 to 7,500 feet Native plant cover type: Rangeland Mean annual precipitation: 20 to 25 inches Available water capacity: Mainly 8.3 inches Frost-free period: 50 to 70 days

Roy and similar soils Major Component Description Composition: 30 percent Geomorphic description: Landslide Mowbray and similar soils Slope: 8 to 35 percent Composition: 35 percent Elevation: 5,300 to 6,200 feet Geomorphic description: Landslide Effective annual precipitation: 17 to 20 inches Slope: 15 to 35 percent Frost-free period: 70 to 90 days Elevation: 6,000 to 7,500 feet Surface layer texture: Very stony clay loam Effective annual precipitation: 20 to 25 inches Rock fragments on the soil surface: 0.01 to 0.10 Frost-free period: 50 to 70 days percent boulders, 67 to 133 feet apart Surface layer texture: Channery loam Drainage class: Well drained Drainage class: Well drained Parent material: Clayey colluvium weathered from Parent material: Gravelly colluvium weathered from sandstone and shale calcareous sandstone Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 4.7 inches Available water capacity: Mainly 4.7 inches 310 Soil Survey

Bridger and similar soils Elevation: 6,000 to 7,500 feet Composition: 30 percent Effective annual precipitation: 20 to 25 inches Geomorphic description: Landslide Frost-free period: 50 to 70 days Slope: 4 to 35 percent Surface layer texture: Gravelly sandy loam Elevation: 6,000 to 7,500 feet Drainage class: Well drained Effective annual precipitation: 20 to 25 inches Parent material: Sandy and gravelly alluvium Frost-free period: 50 to 70 days Native plant cover type: Forestland Surface layer texture: Stony clay loam Available water capacity: Mainly 3.6 inches Drainage class: Well drained Parent material: Silty and clayey alluvium Tiban and similar soils Native plant cover type: Rangeland Composition: 30 percent Available water capacity: Mainly 7.7 inches Geomorphic description: Stream terrace Slope: 0 to 8 percent Novary and similar soils Elevation: 6,000 to 7,500 feet Composition: 20 percent Effective annual precipitation: 20 to 25 inches Geomorphic description: Frost-free period: 50 to 70 days • Pothole on landslide Surface layer texture: Gravelly loam • Swale on landslide Drainage class: Well drained Slope: 0 to 6 percent Parent material: Gravelly colluvium Elevation: 6,000 to 7,500 feet Native plant cover type: Forestland Effective annual precipitation: 20 to 25 inches Available water capacity: Mainly 6.2 inches Frost-free period: 50 to 70 days Surface layer texture: Loam Beehive and similar soils Drainage class: Poorly drained Composition: 25 percent Parent material: Loamy alluvium Geomorphic description: Flood plain Native plant cover type: Rangeland Slope: 0 to 4 percent Flooding: Rare Elevation: 6,000 to 7,500 feet Water table: Present Effective annual precipitation: 20 to 25 inches Available water capacity: Mainly 9.5 inches Frost-free period: 50 to 70 days Surface layer texture: Gravelly sandy loam Additional Components Drainage class: Somewhat poorly drained Adel and similar soils: 5 percent Parent material: Sandy and gravelly alluvium Libeg and similar soils: 5 percent Native plant cover type: Forestland Mowbray and similar soils: 3 percent Flooding: Frequent Tibson and similar soils: 2 percent Water table: Present Available water capacity: Mainly 2.6 inches Management Additional Components For management information about this map unit, see appropriate sections in Part II of this publication. Libeg and similar soils: 5 percent Novary and similar soils: 5 percent 431C—Bearmouth-Tiban-Beehive Management complex, 0 to 8 percent slopes For management information about this map unit, see appropriate sections in Part II of this publication. Setting Elevation: 6,000 to 7,500 feet Mean annual precipitation: 20 to 25 inches 432E—Wayden-Amherst-Winifred Frost-free period: 50 to 70 days complex, 8 to 45 percent slopes Major Component Description Setting Bearmouth and similar soils Composition: 35 percent Elevation: 5,300 to 6,200 feet Geomorphic description: Stream terrace Mean annual precipitation: 17 to 20 inches Slope: 0 to 4 percent Frost-free period: 70 to 90 days Sweet Grass County Area, Montana—Part I 311

Major Component Description Additional Components Wayden and similar soils Bowery and similar soils: 4 percent Composition: 35 percent Bacbuster and similar soils: 3 percent Geomorphic description: Work and similar soils: 3 percent • Side slope shoulder on hill Management • Nose slope shoulder on hill • Nose slope summit on hill For management information about this map unit, Slope: 8 to 45 percent see appropriate sections in Part II of this publication. Elevation: 5,300 to 6,200 feet Effective annual precipitation: 17 to 20 inches Frost-free period: 70 to 90 days 433D—Monaberg loam, 4 to 15 percent Surface layer texture: Clay slopes Depth to bedrock (paralithic): 10 to 20 inches Drainage class: Well drained Parent material: Clayey residuum weathered from Setting shale and siltstone Elevation: 6,000 to 7,500 feet Native plant cover type: Rangeland Mean annual precipitation: 20 to 25 inches Available water capacity: Mainly 2.7 inches Frost-free period: 50 to 70 days Amherst and similar soils Major Component Description Composition: 30 percent Monaberg and similar soils Geomorphic description: Composition: 85 percent • Nose slope shoulder on hill Geomorphic description: Fan • Nose slope summit on hill Slope: 4 to 15 percent Slope: 8 to 45 percent Elevation: 6,000 to 7,500 feet Elevation: 5,300 to 6,200 feet Effective annual precipitation: 20 to 25 inches Effective annual precipitation: 17 to 20 inches Frost-free period: 50 to 70 days Frost-free period: 70 to 90 days Surface layer texture: Loam Surface layer texture: Gravelly clay loam Drainage class: Well drained Depth to bedrock (lithic): 10 to 20 inches Parent material: Loamy alluvium or colluvium Drainage class: Well drained Native plant cover type: Rangeland Parent material: Clayey residuum weathered from Available water capacity: Mainly 9.9 inches andesite Native plant cover type: Forestland Additional Components Available water capacity: Mainly 2.5 inches Adel and similar soils: 5 percent Winifred and similar soils Bridger and similar soils: 5 percent Composition: 25 percent Millerlake and similar soils: 5 percent Geomorphic description: • Side slope backslope on hill Management • Base slope footslope on hill For management information about this map unit, • Base slope backslope on hill see appropriate sections in Part II of this publication. Slope: 8 to 45 percent Elevation: 5,300 to 6,200 feet Effective annual precipitation: 17 to 20 inches Frost-free period: 70 to 90 days 434F—Redchief-Arrowpeak, moist Surface layer texture: Cobbly clay loam complex, 15 to 60 percent slopes Depth to bedrock (paralithic): 20 to 40 inches Drainage class: Well drained Setting Parent material: Clayey residuum weathered from sandstone and shale Elevation: 5,500 to 7,500 feet Native plant cover type: Rangeland Mean annual precipitation: 20 to 25 inches Available water capacity: Mainly 5.3 inches Frost-free period: 50 to 70 days 312 Soil Survey

Major Component Description Major Component Description Redchief and similar soils Bridger and similar soils Composition: 50 percent Composition: 85 percent Geomorphic description: Mountainbase on mountain Geomorphic description: Fan Slope: 15 to 60 percent Slope: 2 to 8 percent Elevation: 5,500 to 7,500 feet Elevation: 6,000 to 7,500 feet Effective annual precipitation: 20 to 25 inches Effective annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Frost-free period: 50 to 70 days Surface layer texture: Stony loam Surface layer texture: Clay loam Drainage class: Well drained Drainage class: Well drained Parent material: Gravelly alluvium Parent material: Silty and clayey alluvium Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 4.8 inches Available water capacity: Mainly 7.9 inches Note: This soil exists on the middle one third of the Additional Components landform. Adel and similar soils: 5 percent Arrowpeak and similar soils Libeg and similar soils: 5 percent Composition: 35 percent Millerlake and similar soils: 5 percent Geomorphic description: Mountainbase on mountain Management Slope: 25 to 60 percent Elevation: 5,500 to 7,500 feet For management information about this map unit, Effective annual precipitation: 20 to 25 inches see appropriate sections in Part II of this publication. Frost-free period: 50 to 70 days Surface layer texture: Very channery loam Depth to bedrock (lithic): 10 to 20 inches 436D—Bowery loam, 2 to 15 percent Drainage class: Well drained slopes Parent material: Residuum weathered from gabbro Native plant cover type: Forestland Setting Available water capacity: Mainly 1.3 inches Elevation: 5,300 to 6,200 feet Note: This soil exists on the upper one third of the Mean annual precipitation: 17 to 20 inches landform. Frost-free period: 70 to 90 days Additional Components Major Component Description Bridger and similar soils: 7 percent Bowery and similar soils Note: This soil exists on the lower one third of the Composition: 85 percent landform. Geomorphic description: Fan and swale Cheadle and similar soils: 5 percent Slope: 2 to 15 percent Note: This soil exists on the upper one third of the Elevation: 5,300 to 6,200 feet landform. Effective annual precipitation: 17 to 20 inches Adel and similar soils: 3 percent Frost-free period: 70 to 90 days Management Surface layer texture: Loam Drainage class: Well drained For management information about this map unit, Parent material: Loamy alluvium or colluvium see appropriate sections in Part II of this publication. Native plant cover type: Rangeland Available water capacity: Mainly 10.6 inches 435C—Bridger clay loam, 2 to 8 percent Additional Components slopes Work and similar soils: 7 percent Farnuf and similar soils: 5 percent Shawmut and similar soils: 3 percent Setting Management Elevation: 6,000 to 7,500 feet Mean annual precipitation: 20 to 25 inches For management information about this map unit, Frost-free period: 50 to 70 days see appropriate sections in Part II of this publication. Sweet Grass County Area, Montana—Part I 313

437E—Cabba-Castner-Work complex, Work and similar soils 4 to 35 percent slopes, bouldery Composition: 20 percent Geomorphic description: • Base slope footslope on hill Setting • Base slope toeslope on hill Field investigation intensity: Order 2 Slope: 4 to 35 percent Elevation: 5,300 to 6,200 feet Elevation: 5,300 to 6,200 feet Mean annual precipitation: 17 to 20 inches Effective annual precipitation: 17 to 20 inches Frost-free period: 70 to 90 days Frost-free period: 70 to 90 days Surface layer texture: Stony loam Major Component Description Rock fragments on the soil surface: 0.01 to 0.10 percent boulders, 67 to 133 feet apart Cabba and similar soils Drainage class: Well drained Composition: 40 percent Parent material: Clayey alluvium Geomorphic description: Native plant cover type: Rangeland • Nose slope summit on hill Available water capacity: Mainly 8.3 inches • Nose slope backslope on hill • Side slope backslope on hill Additional Components Slope: 4 to 35 percent Wayden and similar soils: 5 percent Elevation: 5,300 to 6,200 feet Farnuf and similar soils: 3 percent Effective annual precipitation: 17 to 20 inches Rock outcrop: 2 percent Frost-free period: 70 to 90 days Surface layer texture: Very stony loam Management Rock fragments on the soil surface: 0.01 to For management information about this map unit, 0.10 percent boulders, 67 to 133 feet apart see appropriate sections in Part II of this publication. Depth to bedrock (paralithic): 10 to 20 inches Drainage class: Well drained Parent material: Loamy residuum weathered from 438F—Wayden-Castner complex, sandstone and siltstone 15 to 60 percent slopes, bouldery Native plant cover type: Rangeland Available water capacity: Mainly 2.3 inches Setting Castner and similar soils Elevation: 5,300 to 6,200 feet Composition: 30 percent Mean annual precipitation: 17 to 20 inches Geomorphic description: Frost-free period: 70 to 90 days • Nose slope summit on hill Major Component Description • Nose slope shoulder on hill Slope: 8 to 35 percent Wayden and similar soils Elevation: 5,300 to 6,200 feet Composition: 50 percent Effective annual precipitation: 17 to 20 inches Geomorphic description: Frost-free period: 70 to 90 days • Nose slope summit on escarpment Surface layer texture: Bouldery loam • Side slope shoulder on escarpment Rock fragments on the soil surface: 0.01 to • Nose slope shoulder on escarpment 0.10 percent boulders, 67 to 133 feet apart Slope: 15 to 60 percent Depth to bedrock (lithic): 10 to 20 inches Elevation: 5,300 to 6,200 feet Drainage class: Well drained Effective annual precipitation: 17 to 20 inches Parent material: Residuum weathered from Frost-free period: 70 to 90 days sandstone Surface layer texture: Clay loam Native plant cover type: Rangeland Rock fragments on the soil surface: 0.01 to Available water capacity: Mainly 1.5 inches 0.10 percent boulders, 67 to 133 feet apart 314 Soil Survey

Depth to bedrock (paralithic): 10 to 20 inches Drainage class: Somewhat poorly drained Drainage class: Well drained Parent material: Loamy alluvium Parent material: Clayey residuum weathered from Native plant cover type: Rangeland shale and siltstone Flooding: Rare Native plant cover type: Rangeland Water table: Present Available water capacity: Mainly 2.8 inches Available water capacity: Mainly 9.1 inches

Castner and similar soils Korchea and similar soils Composition: 40 percent Composition: 40 percent Geomorphic description: Geomorphic description: Flood-plain step • Nose slope summit on escarpment Slope: 0 to 4 percent • Nose slope shoulder on escarpment Elevation: 3,750 to 5,200 feet Slope: 35 to 60 percent Effective annual precipitation: 10 to 14 inches Elevation: 5,300 to 6,200 feet Frost-free period: 95 to 125 days Effective annual precipitation: 17 to 20 inches Surface layer texture: Loam Frost-free period: 70 to 90 days Drainage class: Well drained Surface layer texture: Bouldery loam Parent material: Loamy alluvium Rock fragments on the soil surface: 0.01 to Native plant cover type: Rangeland 0.10 percent boulders, 67 to 133 feet apart Flooding: Rare Depth to bedrock (lithic): 10 to 20 inches Available water capacity: Mainly 10.1 inches Drainage class: Well drained Additional Components Parent material: Residuum weathered from sandstone Havre and similar soils: 5 percent Native plant cover type: Rangeland Kremlin and similar soils: 4 percent Available water capacity: Mainly 1.5 inches Yamacall and similar soils: 3 percent Richey and similar soils: 2 percent Additional Components Larry and similar soils: 1 percent Cabba and similar soils: 3 percent Management Winifred and similar soils: 3 percent Amor and similar soils: 2 percent For management information about this map unit, Rock outcrop: 2 percent see appropriate sections in Part II of this publication. Management For management information about this map unit, 440C—Marmarth-Rentsac complex, see appropriate sections in Part II of this publication. 2 to 8 percent slopes

Setting 439B—Fairway-Korchea loams, channeled, 0 to 4 percent slopes Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Setting Major Component Description Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Marmarth and similar soils Frost-free period: 95 to 125 days Composition: 50 percent Geomorphic description: Plain and swale Major Component Description Slope: 2 to 8 percent Fairway and similar soils Elevation: 3,750 to 5,200 feet Composition: 45 percent Effective annual precipitation: 10 to 14 inches Geomorphic description: Flood plain Frost-free period: 95 to 125 days Slope: 0 to 4 percent Surface layer texture: Loam Elevation: 3,750 to 5,200 feet Depth to bedrock (paralithic): 20 to 40 inches Effective annual precipitation: 10 to 14 inches Drainage class: Well drained Frost-free period: 95 to 125 days Parent material: Loamy residuum weathered from Surface layer texture: Loam sandstone and siltstone Sweet Grass County Area, Montana—Part I 315

Native plant cover type: Rangeland Native plant cover type: Rangeland Available water capacity: Mainly 5.6 inches Available water capacity: Mainly 5.6 inches

Rentsac and similar soils Rentsac and similar soils Composition: 40 percent Composition: 40 percent Geomorphic description: Knoll and plain Geomorphic description: Slope: 2 to 8 percent • Nose slope summit on hill Elevation: 3,750 to 5,200 feet • Nose slope shoulder on hill Effective annual precipitation: 10 to 14 inches Slope: 8 to 15 percent Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Surface layer texture: Channery loam Effective annual precipitation: 10 to 14 inches Depth to bedrock (lithic): 10 to 20 inches Frost-free period: 95 to 125 days Drainage class: Well drained Surface layer texture: Channery loam Parent material: Residuum weathered from Depth to bedrock (lithic): 10 to 20 inches calcareous sandstone Drainage class: Well drained Native plant cover type: Rangeland Parent material: Residuum weathered from Available water capacity: Mainly 1.4 inches calcareous sandstone Native plant cover type: Rangeland Additional Components Available water capacity: Mainly 1.4 inches Tanna and similar soils: 4 percent Additional Components Cabbart and similar soils: 3 percent Evanston and similar soils: 2 percent Tanna and similar soils: 4 percent Twilight and similar soils: 1 percent Cabbart and similar soils: 3 percent Evanston and similar soils: 2 percent Management Rock outcrop: 1 percent For management information about this map unit, Management see appropriate sections in Part II of this publication. For management information about this map unit, see appropriate sections in Part II of this publication. 440D—Marmarth-Rentsac complex, 8 to 15 percent slopes 441D—Yawdim-Delpoint complex, Setting 2 to 15 percent slopes Elevation: 3,750 to 5,200 feet Setting Mean annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Major Component Description Frost-free period: 95 to 125 days Marmarth and similar soils Major Component Description Composition: 50 percent Geomorphic description: Yawdim and similar soils • Base slope backslope on hill Composition: 50 percent • Side slope backslope on hill Geomorphic description: • Base slope footslope on hill • Nose slope summit on hill Slope: 8 to 15 percent • Nose slope shoulder on hill Elevation: 3,750 to 5,200 feet • Side slope shoulder on hill Effective annual precipitation: 10 to 14 inches Slope: 2 to 15 percent Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Surface layer texture: Loam Effective annual precipitation: 10 to 14 inches Depth to bedrock (paralithic): 20 to 40 inches Frost-free period: 95 to 125 days Drainage class: Well drained Surface layer texture: Clay Parent material: Loamy residuum weathered from Depth to bedrock (paralithic): 10 to 20 inches sandstone and siltstone Drainage class: Well drained 316 Soil Survey

Parent material: Clayey residuum weathered from Native plant cover type: Rangeland calcareous shale Available water capacity: Mainly 4.2 inches Native plant cover type: Rangeland Available water capacity: Mainly 2.4 inches Yawdim and similar soils Composition: 40 percent Delpoint and similar soils Geomorphic description: Knoll and plain Composition: 40 percent Slope: 2 to 8 percent Geomorphic description: Elevation: 3,750 to 5,200 feet • Side slope backslope on hill Effective annual precipitation: 10 to 14 inches • Base slope footslope on hill Frost-free period: 95 to 125 days • Base slope backslope on hill Surface layer texture: Clay Slope: 2 to 15 percent Depth to bedrock (paralithic): 10 to 20 inches Elevation: 3,750 to 5,200 feet Drainage class: Well drained Effective annual precipitation: 10 to 14 inches Parent material: Clayey residuum weathered from Frost-free period: 95 to 125 days calcareous shale Surface layer texture: Loam Native plant cover type: Rangeland Depth to bedrock (paralithic): 20 to 40 inches Available water capacity: Mainly 2.4 inches Drainage class: Well drained Additional Components Parent material: Loamy residuum weathered from sandstone and siltstone Marmarth and similar soils: 4 percent Native plant cover type: Rangeland Cabbart and similar soils: 3 percent Available water capacity: Mainly 4.6 inches Megonot and similar soils: 3 percent Additional Components Management Megonot and similar soils: 4 percent For management information about this map unit, Cabbart and similar soils: 3 percent see appropriate sections in Part II of this publication. Yamacall and similar soils: 3 percent Management 443B—Sieben-Attewan gravelly loams, For management information about this map unit, 0 to 4 percent slopes see appropriate sections in Part II of this publication. Setting 442C—Tanna-Yawdim complex, Elevation: 3,750 to 5,200 feet 2 to 8 percent slopes Mean annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Setting Major Component Description Elevation: 3,750 to 5,200 feet Sieben and similar soils Mean annual precipitation: 10 to 14 inches Composition: 50 percent Frost-free period: 95 to 125 days Geomorphic description: Tread on terrace Slope: 2 to 4 percent Major Component Description Elevation: 3,750 to 5,200 feet Tanna and similar soils Effective annual precipitation: 10 to 14 inches Composition: 50 percent Frost-free period: 95 to 125 days Geomorphic description: Plain and swale Surface layer texture: Gravelly loam Slope: 2 to 8 percent Drainage class: Well drained Elevation: 3,750 to 5,200 feet Parent material: Gravelly alluvium Effective annual precipitation: 10 to 14 inches Native plant cover type: Rangeland Frost-free period: 95 to 125 days Available water capacity: Mainly 3.9 inches Surface layer texture: Clay loam Depth to bedrock (paralithic): 20 to 40 inches Attewan and similar soils Drainage class: Well drained Composition: 40 percent Parent material: Clayey residuum weathered from Geomorphic description: Tread on terrace sandstone and shale Slope: 0 to 4 percent Sweet Grass County Area, Montana—Part I 317

Elevation: 3,750 to 5,200 feet Parent material: Clayey alluvium Effective annual precipitation: 10 to 14 inches Native plant cover type: Rangeland Frost-free period: 95 to 125 days Available water capacity: Mainly 9.7 inches Surface layer texture: Gravelly loam Additional Components Drainage class: Well drained Parent material: Loamy over sandy and gravelly Evanston and similar soils: 3 percent alluvium Tanna and similar soils: 3 percent Native plant cover type: Rangeland Cabbart and similar soils: 2 percent Available water capacity: Mainly 4.3 inches Rentsac and similar soils: 1 percent Yamacall and similar soils: 1 percent Additional Components Management Verson and similar soils: 4 percent Evanston and similar soils: 3 percent For management information about this map unit, Sixbeacon and similar soils: 3 percent see appropriate sections in Part II of this publication. Management For management information about this map unit, 444D—Boxwell-Ethridge complex, see appropriate sections in Part II of this publication. 8 to 15 percent slopes

444C—Boxwell-Ethridge complex, Setting 2 to 8 percent slopes Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Setting Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Major Component Description Mean annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Boxwell and similar soils Composition: 45 percent Major Component Description Geomorphic description: Plain and swale Boxwell and similar soils Slope: 8 to 15 percent Composition: 50 percent Elevation: 3,750 to 5,200 feet Geomorphic description: Plain and swale Effective annual precipitation: 10 to 14 inches Slope: 2 to 8 percent Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Surface layer texture: Loam Effective annual precipitation: 10 to 14 inches Depth to bedrock (paralithic): 20 to 40 inches Frost-free period: 95 to 125 days Drainage class: Well drained Surface layer texture: Loam Parent material: Loamy residuum weathered from Depth to bedrock (paralithic): 20 to 40 inches sandstone and siltstone Drainage class: Well drained Native plant cover type: Rangeland Parent material: Loamy residuum weathered from Available water capacity: Mainly 5.0 inches sandstone and siltstone Native plant cover type: Rangeland Ethridge and similar soils Available water capacity: Mainly 5.0 inches Composition: 40 percent Geomorphic description: Plain and swale Ethridge and similar soils Slope: 8 to 15 percent Composition: 40 percent Elevation: 3,750 to 5,200 feet Geomorphic description: Plain and swale Effective annual precipitation: 10 to 14 inches Slope: 2 to 8 percent Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Surface layer texture: Clay loam Effective annual precipitation: 10 to 14 inches Drainage class: Well drained Frost-free period: 95 to 125 days Parent material: Clayey alluvium Surface layer texture: Clay loam Native plant cover type: Rangeland Drainage class: Well drained Available water capacity: Mainly 9.7 inches 318 Soil Survey

Additional Components Additional Components Evanston and similar soils: 3 percent Ethridge and similar soils: 3 percent Greybear and similar soils: 3 percent Marmarth and similar soils: 3 percent Tanna and similar soils: 3 percent Cabbart and similar soils: 2 percent Cabbart and similar soils: 2 percent Hinterland and similar soils: 2 percent Marmarth and similar soils: 2 percent Management Rentsac and similar soils: 1 percent Yamacall and similar soils: 1 percent For management information about this map unit, see appropriate sections in Part II of this publication. Management For management information about this map unit, see appropriate sections in Part II of this publication. 446B—Beaverell very cobbly loam, 0 to 4 percent slopes

445C—Evanston-Tanna complex, Setting 2 to 8 percent slopes Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Setting Frost-free period: 95 to 125 days Elevation: 3,750 to 5,200 feet Major Component Description Mean annual precipitation: 10 to 14 inches Beaverell and similar soils Frost-free period: 95 to 125 days Composition: 85 percent Major Component Description Geomorphic description: Tread on terrace Slope: 0 to 4 percent Evanston and similar soils Elevation: 3,750 to 5,200 feet Composition: 50 percent Effective annual precipitation: 10 to 14 inches Geomorphic description: Plain and swale Frost-free period: 95 to 125 days Slope: 2 to 8 percent Surface layer texture: Very cobbly loam Elevation: 3,750 to 5,200 feet Drainage class: Well drained Effective annual precipitation: 10 to 14 inches Parent material: Gravelly alluvium Frost-free period: 95 to 125 days Native plant cover type: Rangeland Surface layer texture: Loam Available water capacity: Mainly 2.5 inches Drainage class: Well drained Parent material: Loamy alluvium Additional Components Native plant cover type: Rangeland Attewan and similar soils: 5 percent Available water capacity: Mainly 9.9 inches Radersburg and similar soils: 5 percent Verson and similar soils: 5 percent Tanna and similar soils Composition: 40 percent Management Geomorphic description: Plain and swale For management information about this map unit, Slope: 2 to 8 percent see appropriate sections in Part II of this publication. Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days 447B—Frenchcreek very gravelly loam, Surface layer texture: Clay loam 2 to 4 percent slopes Depth to bedrock (paralithic): 20 to 40 inches Drainage class: Well drained Setting Parent material: Clayey residuum weathered from sandstone and shale Elevation: 3,750 to 5,200 feet Native plant cover type: Rangeland Mean annual precipitation: 10 to 14 inches Available water capacity: Mainly 4.2 inches Frost-free period: 95 to 125 days Sweet Grass County Area, Montana—Part I 319

Major Component Description Management Frenchcreek and similar soils For management information about this map unit, Composition: 85 percent see appropriate sections in Part II of this publication. Geomorphic description: Tread on stream terrace Slope: 2 to 4 percent Elevation: 3,750 to 5,200 feet 449E—Redchief very stony loam, Effective annual precipitation: 10 to 14 inches 15 to 35 percent slopes Frost-free period: 95 to 125 days Surface layer texture: Very gravelly loam Setting Drainage class: Well drained Elevation: 6,000 to 7,500 feet Parent material: Gravelly alluvium Mean annual precipitation: 20 to 25 inches Native plant cover type: Rangeland Frost-free period: 50 to 70 days Available water capacity: Mainly 2.9 inches Major Component Description Additional Components Redchief and similar soils Attewan and similar soils: 5 percent Composition: 85 percent Sieben and similar soils: 5 percent Geomorphic description: Tread on terrace Sixbeacon and similar soils: 5 percent Slope: 15 to 35 percent Management Elevation: 6,000 to 7,500 feet Effective annual precipitation: 20 to 25 inches For management information about this map unit, Frost-free period: 50 to 70 days see appropriate sections in Part II of this publication. Surface layer texture: Very stony loam Rock fragments on the soil surface: 0.1 to 3.0 percent stones, 3 to 27 feet apart 448B—Attewan loam, 0 to 4 percent Drainage class: Well drained slopes Parent material: Gravelly alluvium Native plant cover type: Rangeland Setting Available water capacity: Mainly 5.4 inches Elevation: 3,750 to 5,200 feet Additional Components Mean annual precipitation: 10 to 14 inches Libeg and similar soils: 5 percent Frost-free period: 95 to 125 days Melville and similar soils: 5 percent Major Component Description Millerlake and similar soils: 5 percent Attewan and similar soils Management Composition: 85 percent For management information about this map unit, Geomorphic description: Tread on terrace see appropriate sections in Part II of this publication. Slope: 0 to 4 percent Elevation: 3,750 to 5,200 feet Effective annual precipitation: 10 to 14 inches 450D—Sieben gravelly loam, Frost-free period: 95 to 125 days 2 to 15 percent slopes Surface layer texture: Loam Drainage class: Well drained Setting Parent material: Loamy over sandy and gravelly alluvium Elevation: 3,750 to 5,200 feet Native plant cover type: Rangeland Mean annual precipitation: 10 to 14 inches Available water capacity: Mainly 4.3 inches Frost-free period: 95 to 125 days Additional Components Major Component Description Evanston and similar soils: 5 percent Sieben and similar soils Radersburg and similar soils: 5 percent Composition: 85 percent Verson and similar soils: 5 percent Geomorphic description: Fan 320 Soil Survey

Slope: 2 to 15 percent Drainage class: Well drained Elevation: 3,750 to 5,200 feet Parent material: Gravelly alluvium Effective annual precipitation: 10 to 14 inches Native plant cover type: Rangeland Frost-free period: 95 to 125 days Available water capacity: Mainly 7.4 inches Surface layer texture: Gravelly loam Additional Components Drainage class: Well drained Parent material: Gravelly alluvium Sixbeacon and similar soils: 3 percent Native plant cover type: Rangeland Yawdim and similar soils: 3 percent Available water capacity: Mainly 3.9 inches Ethridge and similar soils: 2 percent Rock outcrop: 2 percent Additional Components Management Radersburg and similar soils: 5 percent Sixbeacon and similar soils: 5 percent For management information about this map unit, Verson and similar soils: 5 percent see appropriate sections in Part II of this publication. Management For management information about this map unit, 452D—Redchief-Melville complex, see appropriate sections in Part II of this publication. 4 to 15 percent slopes

Setting 451F—Rentsac-Radersburg complex, 15 to 60 percent slopes Elevation: 6,000 to 7,500 feet Mean annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Setting Major Component Description Elevation: 3,750 to 5,200 feet Mean annual precipitation: 10 to 14 inches Redchief and similar soils Frost-free period: 95 to 125 days Composition: 50 percent Geomorphic description: Outwash plain Major Component Description Slope: 4 to 15 percent Rentsac and similar soils Elevation: 6,000 to 7,500 feet Composition: 50 percent Effective annual precipitation: 20 to 25 inches Geomorphic description: Side slope backslope on Frost-free period: 50 to 70 days escarpment Surface layer texture: Very cobbly loam Slope: 15 to 60 percent Drainage class: Well drained Elevation: 3,750 to 5,200 feet Parent material: Gravelly alluvium Effective annual precipitation: 10 to 14 inches Native plant cover type: Rangeland Frost-free period: 95 to 125 days Available water capacity: Mainly 4.7 inches Surface layer texture: Channery loam Depth to bedrock (lithic): 10 to 20 inches Melville and similar soils Drainage class: Well drained Composition: 40 percent Parent material: Residuum weathered from Geomorphic description: Outwash plain calcareous sandstone Slope: 4 to 15 percent Native plant cover type: Rangeland Elevation: 6,000 to 7,500 feet Available water capacity: Mainly 1.4 inches Effective annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Radersburg and similar soils Surface layer texture: Cobbly loam Composition: 40 percent Drainage class: Well drained Geomorphic description: Base slope on escarpment Parent material: Gravelly alluvium and fan Native plant cover type: Forestland Slope: 15 to 60 percent Available water capacity: Mainly 9.0 inches Elevation: 3,750 to 5,200 feet Additional Components Effective annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Adel and similar soils: 5 percent Surface layer texture: Cobbly loam Libeg and similar soils: 5 percent Sweet Grass County Area, Montana—Part I 321

Management Major Component Description For management information about this map unit, Libeg and similar soils see appropriate sections in Part II of this publication. Composition: 85 percent Geomorphic description: • Mountainbase backslope on mountain 453D—Libeg very cobbly sandy loam, • Mountainbase footslope on mountain 2 to 15 percent slopes • Mountainflank backslope on mountain Slope: 15 to 35 percent Elevation: 6,000 to 7,500 feet Setting Effective annual precipitation: 20 to 25 inches Elevation: 6,000 to 7,500 feet Frost-free period: 50 to 70 days Mean annual precipitation: 20 to 25 inches Surface layer texture: Very cobbly sandy loam Frost-free period: 50 to 70 days Rock fragments on the soil surface: 0.01 to 0.10 percent stones, 27 to 67 feet apart Major Component Description Drainage class: Well drained Libeg and similar soils Parent material: Gravelly till Composition: 85 percent Native plant cover type: Rangeland Geomorphic description: Available water capacity: Mainly 3.8 inches • Mountainbase footslope on mountain Additional Components • Mountainbase backslope on mountain • Mountainflank backslope on mountain Adel and similar soils: 5 percent Slope: 2 to 15 percent Monaberg and similar soils: 5 percent Elevation: 6,000 to 7,500 feet Redchief and similar soils: 5 percent Effective annual precipitation: 20 to 25 inches Management Frost-free period: 50 to 70 days Surface layer texture: Very cobbly sandy loam For management information about this map unit, Rock fragments on the soil surface: 0.01 to 0.10 see appropriate sections in Part II of this publication. percent stones, 27 to 67 feet apart Drainage class: Well drained Parent material: Gravelly till 454F—Redfern-Warwood complex, Native plant cover type: Rangeland 25 to 70 percent slopes Available water capacity: Mainly 3.8 inches Setting Additional Components Elevation: 5,500 to 7,500 feet Adel and similar soils: 5 percent Mean annual precipitation: 20 to 25 inches Monaberg and similar soils: 5 percent Frost-free period: 50 to 70 days Redchief and similar soils: 5 percent Major Component Description Management Redfern and similar soils For management information about this map unit, Composition: 65 percent see appropriate sections in Part II of this publication. Geomorphic description: • Mountaintop summit on mountain 453E—Libeg very cobbly sandy loam, • Mountaintop shoulder on mountain 15 to 35 percent slopes • Mountainflank backslope on mountain Slope: 15 to 60 percent Elevation: 5,500 to 7,500 feet Setting Effective annual precipitation: 20 to 25 inches Elevation: 6,000 to 7,500 feet Frost-free period: 50 to 70 days Mean annual precipitation: 20 to 25 inches Surface layer texture: Very channery loam Frost-free period: 50 to 70 days Depth to bedrock (lithic): 10 to 20 inches 322 Soil Survey

Drainage class: Well drained Native plant cover type: Forestland Parent material: Loamy residuum weathered from Available water capacity: Mainly 2.1 inches sandstone and siltstone Native plant cover type: Forestland Fifer and similar soils Available water capacity: Mainly 2.1 inches Composition: 25 percent Geomorphic description: Warwood and similar soils • Mountaintop summit on mountain Composition: 25 percent • Mountaintop shoulder on mountain Geomorphic description: Mountainbase footslope on Slope: 25 to 60 percent mountain Elevation: 5,500 to 7,500 feet Slope: 35 to 45 percent Effective annual precipitation: 20 to 25 inches Elevation: 5,500 to 7,500 feet Frost-free period: 50 to 70 days Effective annual precipitation: 20 to 25 inches Surface layer texture: Loam Frost-free period: 50 to 70 days Depth to bedrock (paralithic): 10 to 20 inches Surface layer texture: Loam Drainage class: Well drained Drainage class: Well drained Parent material: Loamy residuum weathered from Parent material: Loamy alluvium or colluvium sandstone and siltstone Native plant cover type: Forestland Native plant cover type: Rangeland Available water capacity: Mainly 9.3 inches Available water capacity: Mainly 2.7 inches Additional Components Additional Components Cheadle and similar soils: 5 percent Cheadle and similar soils: 5 percent Fifer and similar soils: 5 percent Warwood and similar soils: 5 percent Management Management For management information about this map unit, For management information about this map unit, see appropriate sections in Part II of this publication. see appropriate sections in Part II of this publication.

455F—Redfern-Fifer complex, 456F—Stemple-Cheadle, moist, complex, 25 to 60 percent slopes 25 to 70 percent slopes Setting Setting Elevation: 5,500 to 7,500 feet Mean annual precipitation: 20 to 25 inches Elevation: 5,500 to 7,500 feet Frost-free period: 50 to 70 days Mean annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Major Component Description Major Component Description Redfern and similar soils Composition: 65 percent Stemple and similar soils Geomorphic description: Composition: 70 percent • Mountainflank backslope on mountain Geomorphic description: • Mountaintop shoulder on mountain • Mountainflank footslope on mountain • Mountaintop summit on mountain • Mountainflank backslope on mountain Slope: 25 to 60 percent Slope: 25 to 70 percent Elevation: 5,500 to 7,500 feet Elevation: 5,500 to 7,500 feet Effective annual precipitation: 20 to 25 inches Effective annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Frost-free period: 50 to 70 days Surface layer texture: Very channery loam Surface layer texture: Very cobbly loam Depth to bedrock (lithic): 10 to 20 inches Drainage class: Well drained Drainage class: Well drained Parent material: Gravelly till Parent material: Loamy residuum weathered from Native plant cover type: Forestland sandstone and siltstone Available water capacity: Mainly 4.0 inches Sweet Grass County Area, Montana—Part I 323

Cheadle and similar soils Gilispie and similar soils Composition: 20 percent Composition: 30 percent Geomorphic description: Geomorphic description: • Mountaintop shoulder on mountain • Mountainflank shoulder on mountain • Mountaintop summit on mountain • Mountaintop summit on mountain Slope: 25 to 70 percent • Mountaintop shoulder on mountain Elevation: 5,500 to 7,500 feet • Mountainflank backslope on mountain Effective annual precipitation: 20 to 25 inches Slope: 2 to 15 percent Frost-free period: 50 to 70 days Elevation: 6,000 to 7,500 feet Surface layer texture: Channery loam Effective annual precipitation: 20 to 25 inches Depth to bedrock (lithic): 10 to 20 inches Frost-free period: 50 to 70 days Drainage class: Well drained Surface layer texture: Gravelly loam Parent material: Residuum weathered from Depth to bedrock (lithic): 10 to 20 inches sandstone Drainage class: Well drained Native plant cover type: Rangeland Parent material: Clayey residuum weathered from Available water capacity: Mainly 1.1 inches sandstone Native plant cover type: Rangeland Additional Components Available water capacity: Mainly 2.0 inches Timberlin and similar soils: 4 percent Elve and similar soils: 3 percent Fifer and similar soils Worock and similar soils: 3 percent Composition: 25 percent Geomorphic description: Management • Mountaintop summit on mountain For management information about this map unit, • Mountaintop shoulder on mountain see appropriate sections in Part II of this publication. Slope: 2 to 15 percent Elevation: 6,000 to 7,500 feet Effective annual precipitation: 20 to 25 inches 457D—Arrowpeak-Gilispie-Fifer complex, Frost-free period: 50 to 70 days 2 to 15 percent slopes Surface layer texture: Loam Depth to bedrock (paralithic): 10 to 20 inches Drainage class: Well drained Setting Parent material: Loamy residuum weathered from sandstone and siltstone Elevation: 6,000 to 7,500 feet Native plant cover type: Rangeland Mean annual precipitation: 20 to 25 inches Available water capacity: Mainly 2.7 inches Frost-free period: 50 to 70 days Additional Components Major Component Description Cheadle and similar soils: 5 percent Arrowpeak and similar soils Lymanson and similar soils: 5 percent Composition: 35 percent Geomorphic description: Management • Mountaintop summit on mountain For management information about this map unit, • Mountaintop shoulder on mountain see appropriate sections in Part II of this publication. Slope: 2 to 15 percent Elevation: 6,000 to 7,500 feet Effective annual precipitation: 20 to 25 inches 458C—Vebar-Castner complex, Frost-free period: 50 to 70 days 2 to 8 percent slopes Surface layer texture: Very channery loam Depth to bedrock (lithic): 10 to 20 inches Setting Drainage class: Well drained Parent material: Residuum weathered from gabbro Elevation: 5,300 to 6,200 feet Native plant cover type: Rangeland Mean annual precipitation: 17 to 20 inches Available water capacity: Mainly 1.3 inches Frost-free period: 70 to 90 days 324 Soil Survey

Major Component Description Major Component Description Vebar and similar soils Newtman and similar soils Composition: 50 percent Composition: 92 percent Geomorphic description: Plain and swale Geomorphic description: Flood plain Slope: 2 to 8 percent Slope: 0 to 2 percent Elevation: 5,300 to 6,200 feet Elevation: 3,750 to 6,000 feet Effective annual precipitation: 17 to 20 inches Effective annual precipitation: 10 to 19 inches Frost-free period: 70 to 90 days Frost-free period: 85 to 125 days Surface layer texture: Fine sandy loam Surface layer texture: Muck Depth to bedrock (paralithic): 20 to 40 inches Drainage class: Very poorly drained Drainage class: Well drained Parent material: Alluvium Parent material: Coarse-loamy alluvium over Native plant cover type: Rangeland residuum weathered from calcareous sandstone Water table: Present Native plant cover type: Rangeland Ponding duration: Long Available water capacity: Mainly 4.3 inches Available water capacity: Mainly 6.6 inches Additional Components Castner and similar soils Composition: 40 percent Swampcreek and similar soils: 8 percent Geomorphic description: Knoll and plain Management Slope: 2 to 8 percent Elevation: 5,300 to 6,200 feet For management information about this map unit, Effective annual precipitation: 17 to 20 inches see appropriate sections in Part II of this publication. Frost-free period: 70 to 90 days Surface layer texture: Channery sandy loam Depth to bedrock (lithic): 10 to 20 inches 460B—Foolhen-Beehive-Bearmouth Drainage class: Well drained complex, 0 to 4 percent slopes Parent material: Residuum weathered from sandstone Native plant cover type: Rangeland Setting Available water capacity: Mainly 1.6 inches Elevation: 6,000 to 7,500 feet Additional Components Mean annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days Cabba and similar soils: 3 percent Reedwest and similar soils: 3 percent Major Component Description Ticell and similar soils: 3 percent Foolhen and similar soils Absarokee and similar soils: 1 percent Composition: 40 percent Management Geomorphic description: Depression and flood plain Slope: 0 to 2 percent For management information about this map unit, Elevation: 6,000 to 7,500 feet see appropriate sections in Part II of this publication. Effective annual precipitation: 20 to 25 inches Frost-free period: 50 to 70 days 459A—Newtman muck, 0 to 2 percent Surface layer texture: Sandy loam slopes Drainage class: Very poorly drained Parent material: Sandy and gravelly alluvium Native plant cover type: Rangeland Setting Flooding: Frequent Elevation: 3,750 to 6,000 feet Water table: Present Mean annual precipitation: 10 to 19 inches Ponding duration: Long Frost-free period: 85 to 125 days Available water capacity: Mainly 8.0 inches Sweet Grass County Area, Montana—Part I 325

Beehive and similar soils Slope: 0 to 2 percent Composition: 30 percent Elevation: 3,750 to 5,200 feet Geomorphic description: Flood plain Effective annual precipitation: 10 to 14 inches Slope: 0 to 4 percent Frost-free period: 95 to 125 days Elevation: 6,000 to 7,500 feet Surface layer texture: Clay loam Effective annual precipitation: 20 to 25 inches Drainage class: Somewhat poorly drained Frost-free period: 50 to 70 days Parent material: Clayey alluvium Surface layer texture: Gravelly sandy loam Native plant cover type: Rangeland Drainage class: Somewhat poorly drained Flooding: Rare Parent material: Sandy and gravelly alluvium Water table: Present Native plant cover type: Forestland Available water capacity: Mainly 9.4 inches Flooding: Frequent Water table: Present Absher and similar soils Available water capacity: Mainly 2.6 inches Composition: 40 percent Geomorphic description: Stream terrace Bearmouth and similar soils Slope: 0 to 4 percent Composition: 20 percent Elevation: 3,750 to 5,200 feet Geomorphic description: Stream terrace Effective annual precipitation: 10 to 14 inches Slope: 0 to 4 percent Frost-free period: 95 to 125 days Elevation: 6,000 to 7,500 feet Surface layer texture: Clay Effective annual precipitation: 20 to 25 inches Drainage class: Somewhat poorly drained Frost-free period: 50 to 70 days Parent material: Silty and clayey alluvium Surface layer texture: Gravelly sandy loam Native plant cover type: Rangeland Drainage class: Well drained Water table: Present Parent material: Sandy and gravelly alluvium Salt affected: Saline within 30 inches Native plant cover type: Forestland Sodium affected: Sodic within 30 inches Available water capacity: Mainly 3.6 inches Available water capacity: Mainly 3.8 inches Additional Components Additional Components Libeg and similar soils: 5 percent Fairway and similar soils: 5 percent Novary and similar soils: 5 percent Swampcreek and similar soils: 5 percent Yamacall and similar soils: 5 percent Management Management For management information about this map unit, see appropriate sections in Part II of this publication. For management information about this map unit, see appropriate sections in Part II of this publication.

461B—Soapcreek-Absher family complex, 0 to 4 percent slopes DA—Denied access

Setting Setting Elevation: 3,750 to 5,200 feet Major Component Description Mean annual precipitation: 10 to 14 inches Frost-free period: 95 to 125 days Denied access Composition: 100 percent Major Component Description Management Soapcreek and similar soils Composition: 45 percent For management information about this map unit, Geomorphic description: Flood plain see appropriate sections in Part II of this publication. 326

M-W—Water, miscellaneous W—Water

Setting Setting Field investigation intensity: Order 2 Major Component Description Major Component Description Water Water, miscellaneous Composition: 100 percent Composition: 100 percent Management Management For management information about this map unit, For management information about this map unit, see appropriate sections in Part II of this publication. see appropriate sections in Part II of this publication. 327

References

Alexander, R.R., 1966. Site indexes for lodgepole pine with corrections for stand density; instructions for field use. U.S. Department of Agriculture, Forest Service. Rocky Mountain Forest and Range Experiment Station Research Paper, RP-24.

Alt, D.D. 1984. Profiles of Montana geology: A layman’s guide to the treasure state. Montana Bureau of Mines and Geology, Special Publication 89.

American Association of State Highway and Transportation Officials (AASHTO). 1986. Standard specifications for highway materials and methods of sampling and testing. 14th edition, 2 volumes.

American Society for Testing and Materials (ASTM). 1993. Standard classification of soils for engineering purposes. ASTM Standard D 2487-00.

Baker, F.S. 1925. Aspen in the Central Rocky Mountain Region. United States Department of Agriculture Bulletin 1291.

Brickell, J.E. 1968. A method for constructing site index curves from measurements of tree age and height—Its application to inland Douglas-fir. U.S. Department of Agriculture, Forest Service, Intermountain Research Station Research Paper INT-RP-47.

Dahms, W.G. 1964. Gross and net yield tables for lodgepole pine. U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station, Portland, OR, Research Paper PNW-8.

Eyre, F.H. 1980. Forest cover types of the United States and Canada. Society of American Foresters.

Meyer, W.H. 1938 and 1961. Yield of even-aged stands of ponderosa pine. U.S. Department of Agriculture, Technical Bulletin 630. Washington, DC.

Montana Board of Oil and Gas Conservation, 1995. Annual review. Billings, Montana.

Montana State College, Agricultural Experiment Station. 1956. Soils of Sweet Grass County, Soil Reconnaissance of Montana, Preliminary Report. In cooperation with the Division of Soil Survey, Soil Conservation Service, U.S. Department of Agriculture. Bulletin 519.

Myers, C.A. 1967. Yield tables for managed stands of lodgepole pine in Colorado and Wyoming. U.S. Department of Agriculture, Forest Service. Rocky Mountain Forest and Range Experiment Station Research Paper RM-RP-26.

Rayne, T. 1995. Geological Society of America Abstracts. Rocky Mountain section meeting. Bozeman, Montana. 328

Ross, C.P., Andrews, D.A., and I.J. Witkind. 1955. Geologic map of Montana. In cooperation with the Montana Bureau of Mines and Geology. United States Geological Survey Geologic Map 1, scale 1:500,000. (microfiche)

Sauerwein, W.J. 1979. Site index for black cottonwood. Compiled from British Columbia Forest Service data. U.S. Department of Agriculture, Soil Conservation Service, Western Region.

Simons, F.S., T.J. Armbrustmacher, R.M. Van Noy, N.T. Zilka, F.E. Federspiel, and J. Ridenour. 1979. Mineral resources of the Beartooth Primitive Area and vicinity, Carbon, Park, Stillwater, and Sweet Grass Counties, Montana, and Park County, Wyoming. U.S. Geological Survey, Bulletin 1391-F. (Supersedes Open-file report 74-508.).

Smith, D. 1983. Guidebook of the fold and thrust belt, west-central Montana. Montana Bureau of Mines and Geology, Special Publication 86.

Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S. Department of Agriculture Handbook 18.

Soil Survey Staff. 1998. Keys to soil taxonomy. 8th edition. U.S. Department of Agriculture, Natural Resources Conservation Service.

Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service. U.S. Department of Agriculture Handbook 436.

United States Department of Agriculture, Natural Resources Conservation Service. Montana Field Office Technical Guide, Section II. (http://www.nrcs.usda.gov/technical/efotg/)

United States Department of Agriculture, Natural Resources Conservation Service. National forestry handbook, title 190. (http://soils.usda.gov/technical/nfhandbook/)

United States Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 430-VI. (http://soils.usda.gov/technical/handbook/)

United States Department of Agriculture, Natural Resources Conservation Service. 2003. National range and pasture handbook. (http://www.glti.nrcs.usda.gov/technical/publications/nrph.html) 329

Glossary

Ablation till. Loose, permeable till deposited during defined as the difference between the amount of the final downwasting of glacial ice. Lenses of soil water at field moisture capacity and the crudely sorted sand and gravel are common. amount at wilting point. It is commonly expressed Aeration, soil. The exchange of air in soil with air as inches of water per inch of soil. The capacity, from the atmosphere. The air in a well-aerated in inches, in a 60-inch profile or to a limiting layer soil is similar to that in the atmosphere; the air in is expressed as: a poorly aerated soil is considerably higher in Very low ...... 0 to 3.75 carbon dioxide and lower in oxygen. Low ...... 3.75 to 5.0 Aggregate, soil. Many fine particles held in a single Moderate ...... 5.0 to 7.5 mass or cluster. Natural soil aggregates, such as High ...... more than 7.5 granules, blocks, or prisms, are called peds. Clods are aggregates produced by tillage or Avalanche chute. The track or path formed by an logging. avalanche. Alkali (sodic) soil. (See Sodic (alkali) soil.) Backslope. The geomorphic component that forms Alluvial fan. A body of alluvium, with overflow of the steepest inclined surface and principal water and debris flow deposits, whose surface element of many hillslopes. Backslopes in profile forms a segment of a cone that radiates are commonly steep and linear and descend to a downslope from the point where the stream footslope. In terms of gradational process, emerges from a narrow valley onto a less sloping backslopes are erosional forms produced mainly surface. Source uplands range in relief and areal by mass wasting and running water. extent from mountains to gullied terrains on Badland. Steep or very steep, commonly nonstony, hillslopes. barren land dissected by many intermittent Alluvium. Material, such as sand, silt, or clay, drainage channels. Badland is most common in deposited on land by streams. semiarid and arid regions where streams are Alpha,alpha-dipyridyl. A dye that when dissolved entrenched in soft geologic material. Local relief in 1N ammonium acetate is used to detect generally ranges from 25 to 500 feet. Runoff the presence of reduced iron (Fe II) in the soil. potential is very high, and geologic erosion is A positive reaction indicates a type of redox active. feature. Basal area. The area of a cross section of a tree, Animal-unit-month (AUM). The amount of forage generally referring to the section at breast height required by one mature cow of approximately and measured outside the bark. It is a measure of 1,000 pounds weight, with or without a calf, for stand density, commonly expressed in square 1 month. feet. Aquic conditions. Current soil wetness Basal till. Compact glacial till deposited beneath the characterized by saturation, reduction, and redox ice. features. Base saturation. The degree to which material Argillite. Weakly metamorphosed mudstone or shale. having cation-exchange properties is saturated Aspect. The direction in which a slope faces. with exchangeable bases (sum of Ca, Mg, Na, Association, soil. A group of soils or miscellaneous and K), expressed as a percentage of the total areas geographically associated in a cation-exchange capacity. characteristic repeating pattern and defined and Base slope. A geomorphic component of hills delineated as a single map unit. consisting of the concave to linear (perpendicular Available water capacity (available moisture to the contour) slope that, regardless of the capacity). The capacity of soils to hold water lateral shape, forms an apron or wedge at the available for use by most plants. It is commonly bottom of a hillside dominated by colluvium and 330 Soil Survey

slope-wash sediments (for example, slope of a drum, a pole, and wire cables in an alluvium). arrangement similar to that of a rod and reel used Bedding planes. Fine strata, less than 5-millimeters for fishing. To reduce friction and soil disturbance, thick, in unconsolidated alluvial, eolian, felled trees generally are reeled in while one end lacustrine, or marine sediment. is lifted or the entire log is suspended. Bedrock. The solid rock that underlies the soil and Calcareous soil. A soil containing enough calcium other unconsolidated material or that is exposed carbonate (commonly combined with magnesium at the surface. carbonate) to effervesce visibly when treated with Bedrock-floored plain. An extensive nearly level to cold, dilute hydrochloric acid. gently rolling or moderately sloping area that is Caliche. A more or less cemented deposit of calcium underlain by hard bedrock and has a slope of 0 to carbonate in soils of warm-temperate, subhumid 8 percent. to arid areas. Caliche occurs as soft, thin layers in Bench terrace. A raised, level or nearly level strip of the soil or as hard, thick beds directly beneath earth constructed on or nearly on a contour, the solum, or it is exposed at the surface by supported by a barrier of rocks or similar erosion. material, and designed to make the soil suitable California bearing ratio (CBR). The load-supporting for tillage and to prevent accelerated erosion. capacity of a soil as compared to that of standard Blowout. A shallow depression from which all or crushed limestone, expressed as a ratio. First most of the soil material has been removed by standardized in California. A soil having a CBR of the wind. A blowout has a flat or irregular floor 16 supports 16 percent of the load that would be formed by a resistant layer or by an accumulation supported by standard crushed limestone, per of cobbles or gravel. In some blowouts, the water unit area, with the same degree of distortion. table is exposed. Canopy. The leafy crown of trees or shrubs. (See Board foot. A unit of measure of the wood in lumber, Crown.) logs, or trees. The amount of wood in a board Capillary water. Water held as a film around soil 1 foot wide, 1 foot long, and 1 inch thick before particles and in tiny spaces between particles. finishing. Surface tension is the adhesive force that holds Bottom land. The normal flood plain of a stream, capillary water in the soil. subject to flooding. Cation. An ion carrying a positive charge of Boulders. Rock fragments larger than 2 feet electricity. The common soil cations are calcium, (60 centimeters) in diameter. potassium, magnesium, sodium, and hydrogen. Bouldery. Refers to a soil with .01 to 0.1 percent of Cation-exchange capacity. The total amount of the surface covered with boulders. exchangeable cations that can be held by the Bouldery soil material. Soil that is 15 to 35 percent, soil, expressed in terms of milliequivalents per by volume, rock fragments that are dominated by 100 grams of soil at neutrality (pH 7.0) or at some fragments larger than 24 inches (60 centimeters) other stated pH value. The term, as applied to in diameter. soils, is synonymous with base-exchange Breaks. The steep and very steep broken land at the capacity but is more precise in meaning. border of an upland summit that is dissected by Channeled. Refers to a drainage area in which ravines. natural meandering or repeated branching and Breast height. An average height of 4.5 feet above convergence of a streambed have created deeply the ground surface; the point on a tree where incised cuts, either active or abandoned, in diameter measurements are ordinarily taken. alluvial material. Brush management. Use of mechanical, chemical, Channery soil material. A soil that is, by volume, or biological methods to reduce or eliminate more than 15 percent thin, flat fragments of competition from woody vegetation and thus to sandstone, shale, slate, limestone, or schist as allow understory grasses and forbs to recover or much as 6 inches along the longest axis. A single to make conditions favorable for reseeding. Brush piece is called a channer. management increases forage production and Chemical treatment. Control of unwanted vegetation thus reduces the hazard of erosion. It can through the use of chemicals. improve the habitat for some species of wildlife. Chiseling. Tillage with an implement having one or Cable yarding. A method of moving felled trees to a more soil-penetrating points that shatter or nearby central area for transport to a processing loosen hard, compacted layers to a depth below facility. Most cable yarding systems involve use normal plow depth. Sweet Grass County Area, Montana—Part I 331

Cirque. A semicircular, concave, bowl-like area that Complex, soil. A map unit of two or more kinds of has steep faces primarily resulting from erosive soil or miscellaneous areas in such an intricate activity of a mountain glacier. pattern or so small in area that it is not practical Clay. As a soil separate, the mineral soil particles to map them separately at the selected scale of less than 0.002 millimeters in diameter. As a soil mapping. The pattern and proportion of the soils textural class, soil material that is 40 percent or or miscellaneous areas are somewhat similar in more clay, less than 45 percent sand, and less all areas. than 40 percent silt. Concretions. Grains, pellets, or nodules of various Clayey soil. Silty clay, sandy clay, or clay. sizes, shapes, and colors consisting of Clay film. A thin coating of oriented clay on the concentrated compounds or cemented soil surface of a soil aggregate or lining pores or root grains. The composition of most concretions is channels. Synonyms: clay coating, clay skin. unlike that of the surrounding soil. Calcium Claypan. A slowly permeable soil horizon that carbonate and iron oxide are common contains much more clay than the horizons above compounds in concretions. it. A claypan is commonly hard when dry and Conglomerate. A coarse-grained, clastic rock plastic or stiff when wet. composed of rounded or subangular rock Clearcut. A method of forest harvesting that removes fragments more than 2 millimeters in diameter. It the entire stand of trees in one cutting. commonly has a matrix of sand and finer-textured Reproduction is achieved artificially or by natural material. Conglomerate is the consolidated seeding from the adjacent stands. equivalent of gravel. Climax plant community. The stabilized plant Conservation cropping system. Growing crops in community on a particular site. The plant cover combination with needed cultural and reproduces itself and does not change so long as management practices. In a good conservation the environment remains the same. cropping system, the soil-improving crops and Closed depression. A low area completely practices more than offset the effects of the soil- surrounded by higher ground and having no depleting crops and practices. Cropping systems natural outlet. are needed on all tilled soils. Soil-improving Coarse textured soil. Sand or loamy sand. practices in a conservation cropping system Cobble (or cobblestone). A rounded or partly include the use of rotations that contain grasses rounded fragment of rock 3 to 10 inches (7.6 to and legumes and the return of crop residue to the 25 centimeters) in diameter. soil. Other practices include the use of green Cobbly soil material. Material that has 15 to manure crops of grasses and legumes, proper 35 percent, by volume, rounded or partially tillage, adequate fertilization, and weed and pest rounded rock fragments 3 to 10 inches (7.6 to control. 25 centimeters) in diameter. Very cobbly soil Conservation tillage. Any tillage and planting material has 35 to 60 percent of these rock system in which a cover of crop residue is fragments, and extremely cobbly soil material maintained on at least 30 percent of the soil has more than 60 percent. surface after planting in order to reduce the Codominant trees. Trees whose crowns form the hazard of water erosion. In areas where soil general level of the forest canopy and that blowing is the primary concern, a system that receive full light from above but comparatively maintains a cover of at least 1,000 pounds of flat little from the sides. residue of small grain or the equivalent during the COLE (coefficient of linear extensibility). (See critical erosion period. Linear extensibility.) Consistence, soil. Refers to the degree of cohesion Colluvium. Soil material or rock fragments, or both, and adhesion of soil material and its resistance to moved by creep, slide, or local wash and deformation when ruptured. Consistence includes deposited at the base of steep slopes. resistance of soil material to rupture and to Commercial forest. Forestland capable of producing penetration; plasticity, toughness, and stickiness 20 cubic feet or more per acre per year at the of puddled soil material; and the manner in which culmination of mean annual increment. the soil material behaves when subject to Complex slope. Irregular or variable slope. Planning compression. Terms describing consistence are or establishing terraces, diversions, and other defined in the “Soil Survey Manual” (Soil Survey water-control structures on a complex slope is Division Staff, 1993). difficult. 332 Soil Survey

Consolidated sandstone. Sandstone that disperses Deep soil. A soil that is 40 to 60 inches deep over within a few hours when fragments are placed bedrock or to other material that restricts the in water. The fragments are extremely hard or penetration of plant roots. very hard when dry, are not easily crushed, Deferred grazing. Postponing grazing or resting and cannot be textured by the usual field grazing land for a prescribed period. method. Dense layer (in tables). A very firm, massive layer Consolidated shale. Shale that disperses within a that has a bulk density of more than 1.8 grams few hours when fragments are placed in water. per cubic centimeter. Such a layer affects the The fragments are extremely hard or very hard ease of digging and can affect filling and when dry and are not easily crushed. compacting. Contour stripcropping (or contour farming). Depth, soil. Generally, the thickness of the soil over Growing crops in strips that follow the contour. bedrock. Very deep soils are more than 60 inches Strips of grass or close-growing crops are deep over bedrock; deep soils, 40 to 60 inches; alternated with strips of clean-tilled crops or moderately deep, 20 to 40 inches; shallow, 10 to summer fallow. 20 inches; and very shallow, less than 10 inches. Control section. The part of the soil on which Depth to rock (in tables). Bedrock is too near the classification is based. The thickness varies surface for the specified use. among different kinds of soil, but for many it is Dip slope. A slope of the land surface, roughly that part of the soil profile between depths of determined by and approximately conforming to 10 inches and 40 or 80 inches. the dip of the underlying bedrock. Coprogenous earth (sedimentary peat). Fecal Diversion (or diversion terrace). A ridge of earth, material deposited in water by aquatic organisms. generally a terrace, built to protect downslope Corrosion. Soil-induced electrochemical or chemical areas by diverting runoff from its natural course. action that dissolves or weakens concrete or Divided-slope farming. A form of field stripcropping uncoated steel. in which crops are grown in a systematic Cover crop. A close-growing crop grown primarily to arrangement of two strips, or bands, across the improve and protect the soil between periods of slope to reduce the hazard of water erosion. One regular crop production, or a crop grown between strip is in a close-growing crop that provides trees and vines in orchards and vineyards. protection from erosion, and the other strip is in a Crop residue management. Returning crop residue crop that provides less protection from erosion. to the soil, which helps to maintain soil structure, This practice is used where slopes are not long organic matter content, and fertility and helps to enough to permit a full stripcropping pattern to be control erosion. used. Cropping system. Growing crops according to a Dominant trees. Trees whose crowns form the planned system of rotation and management general level of the forest canopy and that practices. receive full light from above and from the sides. Cross-slope farming. Deliberately conducting Drainage class (natural). Refers to the frequency farming operations on sloping farmland in such a and duration of periods of saturation or partial way that tillage is across the general slope. saturation during soil formation, as opposed to Crown. The upper part of a tree or shrub, including altered drainage, which is commonly the result of the living branches and their foliage. artificial drainage or irrigation but may be caused Culmination of the mean annual increment by the sudden deepening of channels or the (CMAI). The average annual increase per acre in blocking of drainage outlets. Seven classes of the volume of a stand. Computed by dividing the natural soil drainage are recognized: total volume of the stand by its age. As the stand Excessively drained.—These soils have very high increases in age, the mean annual increment and high hydraulic conductivity and a low water- continues to increase until mortality begins to holding capacity. They are not suited to crop reduce the rate of increase. The point where the production unless irrigated. stand reaches its maximum annual rate of growth Somewhat excessively drained.—These soils is called the culmination of the mean annual have high hydraulic conductivity and a low water- increment. holding capacity. Without irrigation, only a narrow Decreasers. The most heavily grazed climax range range of crops can be grown, and yields are low. plants. Because they are the most palatable, they Well drained.—These soils have an intermediate are the first to be destroyed by overgrazing. water-holding capacity. They retain optimum Sweet Grass County Area, Montana—Part I 333

amounts of moisture, but they are not wet close Ecological site. An area where climate, soil, and enough to the surface or long enough during the relief are sufficiently uniform to produce a distinct growing season to adversely affect yields. natural plant community. An ecological site is the Moderately well drained.—These soils are wet product of all the environmental factors close enough to the surface or long enough that responsible for its development. It is typified by an planting or harvesting operations or yields of association of species that differ from those on some field crops are adversely affected unless a other ecological sites in kind and/or proportion of drainage system is installed. Moderately well- species or in total production. drained soils commonly have a layer with low Eluviation. The movement of material in true solution hydraulic conductivity, a wet layer relatively high or colloidal suspension from one place to another in the profile, additions of water by seepage, or within the soil. Soil horizons that have lost some combination of these. material through eluviation are eluvial; those that Somewhat poorly drained.—These soils are wet have received material are illuvial. close enough to the surface or long enough that Endosaturation. A type of saturation of the soil in planting or harvesting operations or crop growth which all horizons between the upper boundary is markedly restricted unless a drainage system of saturation and a depth of 2 meters are is installed. Somewhat poorly drained soils saturated. commonly have a layer with low hydraulic Eolian soil material. Earthy parent material conductivity, a wet layer high in the profile, accumulated through wind action; commonly additions of water through seepage, or a refers to sandy material in dunes or to loess in combination of these. blankets on the surface. Poorly drained.—These soils commonly are so Ephemeral stream. A stream, or reach of a stream, wet, at or near the surface, during a considerable that flows only in direct response to precipitation. part of the year that field crops cannot be grown It receives no long-continued supply from melting under natural conditions. Poorly drained snow or other source, and its channel is above conditions are caused by a saturated zone, a the water table at all times. layer with low hydraulic conductivity, seepage, or Episaturation. A type of saturation indicating a a combination of these. perched water table in a soil in which saturated Very poorly drained.—These soils are wet to the layers are underlain by one or more unsaturated surface most of the time. The wetness prevents layers within 2 meters of the surface. the growth of important crops (except rice) unless Erosion. The wearing away of the land surface by a drainage system is installed. water, wind, ice, or other geologic agents and by Drainage, surface. Runoff, or surface flow of water, such processes as gravitational creep. from an area. Erosion (geologic). Erosion caused by geologic Drainageway. An area of ground at a lower elevation processes acting over long geologic periods and than the surrounding ground and in which water resulting in the wearing away of mountains and collects and is drained to a closed depression or the building up of such landscape features as lake or to a drainageway at a lower elevation. A flood plains and coastal plains. Synonym: natural drainageway may or may not have distinctly erosion. incised channels at its upper reaches or Erosion (accelerated). Erosion much more rapid throughout its course. than geologic erosion, mainly as a result of Drumlin. A low, smooth, elongated oval hill, mound, human or animal activities or of a catastrophe in or ridge of compact glacial till. The longer axis is nature, such as fire, that exposes the surface. parallel to the path of the glacier and commonly Erosion pavement. A layer of gravel or stones that has a blunt nose pointing in the direction from remains on the surface after fine particles are which the ice approached. removed by sheet or rill erosion. Duff. A generally firm organic layer on the surface of Escarpment. A relatively continuous and steep slope mineral soils. It consists of fallen plant material or cliff breaking the general continuity of more that is in the process of decomposition and gently sloping land surfaces and resulting from includes everything from the litter on the surface erosion or faulting. Synonym: scarp. to underlying pure humus. Esker. A long, narrow, sinuous, steep-sided ridge Dune. A mound, ridge, or hill of loose, windblown composed of irregularly stratified sand and gravel granular material (generally sand), either bare or that were deposited by a subsurface stream covered with vegetation. flowing between ice walls or through ice tunnels 334 Soil Survey

of a retreating glacier and that were left behind Fluvial. Of or pertaining to rivers; produced by river when the ice melted. Eskers range from less than action, as a fluvial plain. a mile to more than 100 miles in length and from Foothill. A steeply sloping upland that has relief of as 10 to 100 feet in height. much as 1,000 feet (300 meters) and fringes a Even aged. Refers to a stand of trees in which only mountain range or high-plateau escarpment. small differences in age occur between individual Footslope. The geomorphic component that forms trees. A range of 20 years is allowed. the inner, gently inclined surface at the base of a Extrusive rock. Igneous rock derived from deep- hillslope. The surface profile is dominantly seated molten matter (magma) emplaced on the concave. In terms of gradational processes, a earth’s surface. footslope is a transitional zone between an Fallow. Cropland left idle in order to restore upslope site of erosion (backslope) and a productivity through accumulation of moisture. downslope site of deposition (toeslope). Summer fallow is common in regions of limited Forb. Any herbaceous plant not a grass or a sedge. rainfall where cereal grain is grown. The soil is Forest cover. All trees and other woody plants tilled for at least one growing season for weed (underbrush) covering the ground in a forest. control and decomposition of plant residue. Forest type. A stand of trees similar in composition Fertility, soil. The quality that enables a soil to and development because of given physical and provide plant nutrients, in adequate amounts and biological factors by which it may be differentiated in proper balance, for the growth of specified from other stands. plants when light, moisture, temperature, tilth, Fragipan. A loamy, brittle subsurface horizon low in and other growth factors are favorable. porosity and content of organic matter and low or Fibric soil material (peat). The least decomposed of moderate in clay but high in silt or very fine sand. all organic soil material. Peat contains a large A fragipan appears cemented and restricts roots. amount of well-preserved fiber that is readily When dry, it is hard or very hard and has a higher identifiable according to botanical origin. Peat has bulk density than the horizon or horizons above. the lowest bulk density and the highest water When moist, it tends to rupture suddenly under content at saturation of all organic soil material. pressure rather than to deform slowly. Field moisture capacity. The moisture content of a Frost action (in tables). Freezing and thawing of soil soil, expressed as a percentage of the ovendry moisture. Frost action can damage roads, weight, after the gravitational, or free, water has buildings and other structures, and plant roots. drained away; the field moisture content 2 or Genesis, soil. The mode of origin of the soil. Refers 3 days after a soaking rain; also called normal especially to the processes or soil-forming factors field capacity, normal moisture capacity, or responsible for the formation of the solum, or true capillary capacity. soil, from the unconsolidated parent material. Fine textured soil. Sandy clay, silty clay, or clay. Giant ripple mark. The undulating surface sculpture Firebreak. Area cleared of flammable material to produced in noncoherent granular materials by stop or help control creeping or running fires. It currents of water and by the agitation of water in also serves as a line from which to work and to wave action during the draining of large glacial facilitate the movement of firefighters and lakes, such as Glacial Lake Missoula. equipment. Designated roads also serve as Glacial drift. Pulverized and other rock material firebreaks. transported by glacial ice and then deposited. First bottom. The normal flood plain of a stream, Also, the sorted and unsorted material deposited subject to frequent or occasional flooding. by streams flowing from glaciers. Flaggy soil material. Material that has, by volume, Glacial outwash. Gravel, sand, and silt, commonly 15 to 35 percent flagstones. Very flaggy soil stratified, deposited by glacial meltwater. material has 35 to 60 percent flagstones, and Glacial till. Unsorted, nonstratified glacial drift extremely flaggy soil material has more than consisting of clay, silt, sand, and boulders 60 percent flagstones. transported and deposited by glacial ice. Flagstone. A thin fragment of sandstone, limestone, Glaciated uplands. Land areas that were previously slate, shale, or (rarely) schist 6 to 15 inches covered by continental or alpine glaciers and that (15 to 38 centimeters) long. are at a higher elevation than the flood plain. Flood plain. A nearly level alluvial plain that borders Glaciofluvial deposits. Material moved by glaciers a stream and is subject to flooding unless and subsequently sorted and deposited by protected artificially. streams flowing from the melting ice. The Sweet Grass County Area, Montana—Part I 335

deposits are stratified and occur as kames, Head out. To form a flower head. eskers, deltas, and outwash plains. Head slope. A geomorphic component of hills Glaciolacustrine deposits. Material ranging from consisting of a laterally concave area of a hillside, fine clay to sand derived from glaciers and especially at the head of a drainageway. The deposited in glacial lakes mainly by glacial overland waterflow is converging. meltwater. Many deposits are interbedded or Heavy metal. Inorganic substances that are solid at laminated. ordinary temperatures and are not soluble in Gleyed soil. Soil that formed under poor drainage, water. They form oxides and hydroxides that are resulting in the reduction of iron and other basic. Examples are copper, iron, cadmium, zinc, elements in the profile and in gray colors. manganese, lead, and arsenic. Grassed waterway. A natural or constructed Hemic soil material (mucky peat). Organic soil waterway, typically broad and shallow, seeded to material intermediate in degree of decomposition grass as protection against erosion. Conducts between the less decomposed fibric material and surface water away from cropland. the more decomposed sapric material. Gravel. Rounded or angular fragments of rock High-residue crops. Such crops as small grain and as much as 3 inches (2 millimeters to corn used for grain. If properly managed, residue 7.6 centimeters) in diameter. An individual from these crops can be used to control erosion piece is a pebble. until the next crop in the rotation is established. Gravelly soil material. Soil that is 15 to 35 percent, These crops return large amounts of organic by volume, rounded or angular rock fragments up matter to the soil. to 3 inches (7.6 centimeters) in diameter. Very Hill. A natural elevation of the land surface, rising as gravelly soil is 35 to 60 percent gravel, and much as 1,000 feet above surrounding lowlands, extremely gravelly soil is more than 60 percent commonly of limited summit area and having a gravel by volume. well-defined outline; hillsides generally have Grazeable forestland. Land capable of sustaining slopes of more than 8 percent. The distinction livestock grazing by producing forage of sufficient between a hill and a mountain is arbitrary and is quantity during one or more stages of secondary dependent on local usage. forest succession. Horizon, soil. A layer of soil, approximately parallel to Green manure crop (agronomy). A soil-improving the surface, having distinct characteristics crop grown to be plowed under in an early stage produced by soil-forming processes. In the of maturity or soon after maturity. identification of soil horizons, an uppercase letter Ground water. Water filling all the unblocked pores of represents the major horizons. Numbers or the material below the water table. lowercase letters that follow represent Gully. A miniature valley with steep sides cut by subdivisions of the major horizons. An running water and through which water ordinarily explanation of the subdivisions is given in the runs only after rainfall. The distinction between a “Soil Survey Manual” (Soil Survey Division Staff, gully and a rill is one of depth. A gully generally is 1993). The major horizons of mineral soil are as an obstacle to farm machinery and is too deep to follows: be obliterated by ordinary tillage; a rill is of lesser O horizon.—An organic layer of fresh and depth and can be smoothed over by ordinary decaying plant residue. tillage. A horizon.—The mineral horizon at or near the Gypsum. A mineral consisting of hydrous calcium surface in which an accumulation of humified sulfate. organic matter is mixed with the mineral material. Habitat type. An aggregation of all land areas Also, a plowed surface horizon, most of which capable of producing similar climax plant was originally part of a B horizon. communities. E horizon.—The mineral horizon in which the Hard bedrock. Bedrock that cannot be excavated main feature is loss of silicate clay, iron, except by blasting or by the use of special aluminum, or some combination of these. equipment that is not commonly used in B horizon.—The mineral horizon below an A or construction. E horizon. The B horizon is in part a layer of Hardpan. A hardened or cemented soil horizon, or transition from the overlying A to the underlying layer. The soil material is sandy, loamy, or clayey C horizon. The B horizon also has distinctive and is cemented by iron oxide, silica, calcium characteristics, such as (1) accumulation of clay, carbonate, or other substance. sesquioxides, humus, or a combination of these; 336 Soil Survey

(2) prismatic or blocky structure; (3) redder or absolutely impervious to air and water all the browner colors than those in the A horizon; or time. (4) a combination of these. Increasers. Species in the climax vegetation that C horizon.—The mineral horizon or layer, increase in amount as the more desirable plants excluding indurated bedrock, that is little affected are reduced by close grazing. Increasers by soil-forming processes and does not have the commonly are the shorter plants and the less properties typical of the overlying soil material. palatable to livestock. The material of a C horizon may be either like or Infiltration. The downward entry of water into the unlike that in which the solum formed. If the immediate surface of soil or other material, as material is known to differ from that in the solum, contrasted with percolation, which is movement an Arabic numeral, commonly a 2, precedes the of water through soil layers or material. letter C. Infiltration capacity. The maximum rate at which Cr horizon.—Sedimentary beds of consolidated water can infiltrate into a soil under a given set of sandstone and semiconsolidated and conditions. consolidated shale. Generally, roots can Infiltration rate. The rate at which water penetrates penetrate this horizon only along fracture planes. the surface of the soil at any given instant, R layer.—Consolidated bedrock beneath the soil. usually expressed in inches per hour. The rate The bedrock commonly underlies a C horizon, can be limited by the infiltration capacity of the but it can be directly below an A or a B horizon. soil or the rate at which water is applied at the Hornfels. A fine-grained metamorphic rock surface. composed of quartz, feldspar, mica, and other Intake rate. The average rate of water entering the minerals, formed by the action of intrusive rock soil under irrigation. Most soils have a fast initial upon sedimentary rock, especially shale. rate; the rate decreases with application time. Humus. The well decomposed, more or less stable Therefore, intake rate for design purposes is not part of the organic matter in mineral soils. a constant but is a variable depending on the net Hydrologic soil groups. Refers to soils grouped irrigation application. The rate of water intake, in according to their runoff-producing inches per hour, is expressed as follows: characteristics. The chief consideration is the Less than 0.2 ...... very low inherent capacity of soil bare of vegetation to 0.2 to 0.4 ...... low permit infiltration. The slope and the kind of plant 0.4 to 0.75 ...... moderately low cover are not considered but are separate factors 0.75 to 1.25 ...... moderate in predicting runoff. Soils are assigned to four 1.25 to 1.75 ...... moderately high groups. In group A are soils having a high 1.75 to 2.5 ...... high infiltration rate when thoroughly wet and having a More than 2.5 ...... very high low runoff potential. They are mainly deep, well drained, and sandy or gravelly. In group D, at the Interfluve. An elevated area between two other extreme, are soils having a very slow drainageways that sheds water to those infiltration rate and thus a high runoff potential. drainageways. They have a claypan or clay layer at or near the Intermittent stream. A stream, or reach of a surface, have a permanent high water table, or stream, that flows for prolonged periods only are shallow over nearly impervious bedrock or when it receives ground-water discharge or other material. A soil is assigned to two long, continued contributions from melting hydrologic groups if part of the acreage is snow or other surface and shallow subsurface artificially drained and part is undrained. sources. Igneous rock. Rock formed by solidification from a Invaders. On range, plants that encroach into an molten or partially molten state. Major varieties area and grow after the climax vegetation has include plutonic and volcanic rock. Examples are been reduced by grazing. Generally, plants andesite, basalt, and granite. invade following disturbance of the surface. Illuviation. The movement of soil material from one Irrigation. Application of water to soils to assist in horizon to another in the soil profile. Generally, production of crops. Methods of irrigation are: material is removed from an upper horizon and Basin.—Water is applied rapidly to nearly level deposited in a lower horizon. plains surrounded by levees or dikes. Impervious soil. A soil through which water, air, or Border.—Water is applied at the upper end of a roots penetrate slowly or not at all. No soil is strip in which the lateral flow of water is controlled Sweet Grass County Area, Montana—Part I 337

by small earth ridges called border dikes, or Leaching. The removal of soluble material from soil borders. or other material by percolating water. Controlled flooding.—Water is released at Linear extensibility. Refers to the change in length intervals from closely spaced field ditches and of an unconfined clod as moisture content is distributed uniformly over the field. decreased from a moist to a dry state. Linear Corrugation.—Water is applied to small, closely extensibility is used to determine the shrink-swell spaced furrows or ditches in fields of close- potential of soils. It is an expression of the volume growing crops or in orchards so that it flows in change between the water content of the clod at 1 1 only one direction. /3- or /10-bar tension (33kPa or 10kPa tension) Drip (or trickle).—Water is applied slowly and and oven dryness. Volume change is influenced under low pressure to the surface of the soil or by the amount and type of clay minerals in the into the soil through such applicators as emitters, soil. The volume change is the percent change for porous tubing, or perforated pipe. the whole soil. If it is expressed as a fraction, the Furrow.—Water is applied in small ditches made resulting value is COLE, coefficient of linear by cultivation implements. Furrows are used for extensibility. tree and row crops. Liquid limit. The moisture content at which the soil Sprinkler.—Water is sprayed over the soil surface passes from a plastic to a liquid state. through pipes or nozzles from a pressure system. Loam. Soil material that is 7 to 27 percent clay Subirrigation.—Water is applied in open ditches particles, 28 to 50 percent silt particles, and less or tile lines until the water table is raised enough than 52 percent sand particles. to wet the soil. Loamy soil. Coarse sandy loam, sandy loam, fine Wild flooding.—Water, released at high points, is sandy loam, very fine sandy loam, loam, silt allowed to flow onto an area without controlled loam, silt, clay loam, sandy clay loam, or silty clay distribution. loam.

Ksat. Saturated hydraulic conductivity. (See Loess. Fine grained material, dominantly of silt-sized Permeability.) particles, deposited by wind. Kame. A moundlike hill of glacial drift, composed Low-residue crops. Such crops as corn used for chiefly of stratified sand and gravel. silage, peas, beans, and potatoes. Residue from Kame terrace. A terracelike ridge consisting of these crops is not adequate to control erosion stratified sand and gravel that were deposited by until the next crop in the rotation is established. a meltwater stream flowing between a melting These crops return little organic matter to the soil. glacier and a higher valley wall or lateral moraine Low strength. The soil is not strong enough to and that remained after the disappearance of the support loads. ice. It is commonly pitted with kettles and has an Marl. An earthy, unconsolidated deposit consisting irregular ice-contact slope. chiefly of calcium carbonate mixed with clay in Lacustrine deposit. Material deposited in lake water approximately equal amounts. and exposed when the water level is lowered or Masses. Concentrations of substances in the soil the elevation of the land is raised. matrix that do not have a clearly defined Lake plain. A surface marking the floor of an extinct boundary with the surrounding soil material and lake, filled in by well-sorted, stratified sediments. cannot be removed as a discrete unit. Common Landslide. The rapid downhill movement of a mass compounds making up masses are calcium of soil and loose rock, generally when wet or carbonate, gypsum or other soluble salts, iron saturated. The speed and distance of movement, oxide, and manganese oxide. Masses consisting as well as the amount of soil and rock material, of iron oxide or manganese oxide generally are vary greatly. considered a type of redox concentration. Large stones (in tables). Rock fragments 3 inches Mean annual increment (MAI). The average annual (7.6 centimeters) or more across. Large stones increase in volume of a tree during its entire life. adversely affect the specified use of the soil. Mechanical treatment. Use of mechanical Lateral moraine. A ridgelike moraine carried on and equipment for seeding, brush management, and deposited at the side margin of a valley glacier. It other management practices. is composed chiefly of rock fragments derived Medium textured soil. Very fine sandy loam, loam, from the valley walls by glacial abrasion and silt loam, or silt. plucking or by mass wasting. 338 Soil Survey

Merchantable trees. Trees that are of sufficient size Muck. Dark, finely divided, well-decomposed organic to be economically processed into wood soil material. (See Sapric soil material.) products. Mudstone. Sedimentary rock formed by induration of Metamorphic rock. Rock of any origin altered in silt and clay in approximately equal amounts. mineralogical composition, chemical composition, Munsell notation. A designation of color by degrees or structure by heat, pressure, and movement. of three simple variables—hue, value, and Nearly all such rocks are crystalline. chroma. For example, a notation of 10YR 6/4 is Microhigh. An area that is 2 to 12 inches higher than a color with hue of 10YR, value of 6, and chroma the adjacent microlow. of 4. Microlow. An area that is 2 to 12 inches lower than Naturalized pasture. Forestland that is used the adjacent microhigh. primarily for the production of forage for grazing Mineral soil. Soil that is mainly mineral material and by livestock rather than for the production of low in organic material. Its bulk density is more wood products. Overstory trees are removed or than that of organic soil. managed to promote the native and introduced Minimum tillage. Only the tillage essential to crop understory vegetation occurring on the site. This production and prevention of soil damage. vegetation is managed for its forage value Miscellaneous area. An area that has little or no through the use of grazing management natural soil and supports little or no vegetation. principles. Miscellaneous water. A sewage lagoon, an Neutral soil. A soil having a pH value of 6.6 to 7.3. industrial waste pit, a fish hatchery, or a similar (See Reaction, soil.) water area. Nose slope. A geomorphic component of hills Moderately coarse textured soil. Coarse sandy consisting of the projecting end (laterally convex loam, sandy loam, or fine sandy loam. area) of a hillside. The overland waterflow is Moderately deep soil. A soil that is 20 to 40 inches predominantly divergent. deep over bedrock or to other material that Nutrient, plant. Any element taken in by a plant restricts the penetration of plant roots. essential to its growth. Plant nutrients are mainly Moderately fine textured soil. Clay loam, sandy clay nitrogen, phosphorus, potassium, calcium, loam, or silty clay loam. magnesium, sulfur, iron, manganese, copper, Mollic epipedon. A thick, dark, humus-rich surface boron, and zinc obtained from the soil and horizon (or horizons) that has high base carbon, hydrogen, and oxygen obtained from the saturation and pedogenic soil structure. It may air and water. include the upper part of the subsoil. Observed rooting depth. Depth to which roots have Moraine. An accumulation of glacial drift in a been observed to penetrate. topographic landform of its own, resulting chiefly Organic matter. Plant and animal residue in the soil from the direct action of glacial ice. Some types in various stages of decomposition. The content are lateral, recessional, and terminal. of organic matter in the surface layer is described Morphology, soil. The physical makeup of the soil, as follows: including the texture, structure, porosity, Very low ...... less than 0.5 percent consistence, color, and other physical, mineral, Low ...... 0.5 to 1.0 percent and biological properties of the various horizons, Moderately low ...... 1.0 to 2.0 percent and the thickness and arrangement of those Moderate ...... 2.0 to 4.0 percent horizons in the soil profile. High ...... 4.0 to 8.0 percent Mottling, soil. Areas of color that differ from the Very high ...... more than 8.0 percent matrix color. These colors are commonly attributes retained from the geologic parent Outwash plain. An extensive area of glaciofluvial material. (See Redox features for indications of material that was deposited by meltwater poor aeration and impeded drainage.) streams. Mountain. A natural elevation of the land surface, Overstory. The trees in a forest that form the upper rising more than 1,000 feet above surrounding crown cover. lowlands, commonly of restricted summit area Oxbow. The horseshoe-shaped channel of a former (relative to a plateau) and generally having steep meander, remaining after the stream formed a sides. A mountain can occur as a single, isolated cutoff across a narrow meander neck. mass or in a group forming a chain or range. Sweet Grass County Area, Montana—Part I 339

Pan. A compact, dense layer in a soil that impedes drained, the water can be removed only by the movement of water and the growth of roots. percolation or evapotranspiration. For example, hardpan, fragipan, claypan, Poorly graded. Refers to a coarse-grained soil or soil plowpan, and traffic pan. material consisting mainly of particles of nearly Parent material. The unconsolidated organic and the same size. Because there is little difference in mineral material in which soil forms. size of the particles, density can be increased Peat. Unconsolidated material, largely only slightly by compaction. undecomposed organic matter, that has Potential natural community (PNC). The biotic accumulated under excess moisture. (See Fibric community that would become established on an soil material.) ecological site if all successional sequences were Ped. An individual natural soil aggregate, such as a completed without interferences by man under granule, a prism, or a block. the present environmental conditions. Natural Pedon. The smallest volume that can be called disturbances are inherent in its development. The “a soil.” A pedon is three dimensional and large PNC may include acclimatized or naturalized enough to permit study of all horizons. Its nonnative species. area ranges from about 10 to 100 square feet Potential rooting depth (effective rooting depth). (1 square meter to 10 square meters), depending Depth to which roots could penetrate if the on the variability of the soil. content of moisture in the soil were adequate. Percolation. The movement of water through the soil. The soil has no properties restricting the Permeability. The quality of the soil that enables penetration of roots to this depth. water or air to move downward through the Prescribed burning. The application of fire to land profile. under such conditions of weather, soil moisture, Terms describing permeability are: and time of day as presumably will result in the intensity of heat and spread required to Very slow ...... less than 0.06 inch accomplish specific forest management, wildlife, Slow ...... 0.06 to 0.2 inch grazing, or fire hazard reduction purposes. Moderately slow ...... 0.2 to 0.6 inch Productivity, soil. The capability of a soil for Moderate ...... 0.6 to 2.0 inches producing a specified plant or sequence of plants Moderately rapid ...... 2.0 to 6.0 inches under specific management. Rapid ...... 6.0 to 20 inches Profile, soil. A vertical section of the soil extending Very rapid ...... more than 20 inches through all its horizons and into the parent material. pH value. A numerical designation of acidity and Proper grazing use. Grazing at an intensity that alkalinity in soil. (See Reaction, soil.) maintains enough cover to protect the soil and Phase, soil. A subdivision of a soil series based on maintain or improve the quantity and quality of features that affect its use and management, the desirable vegetation. This practice increases such as slope, stoniness, and flooding. the vigor and reproduction capacity of the key Plastic limit. The moisture content at which a soil plants and promotes the accumulation of litter changes from semisolid to plastic. and mulch necessary to conserve soil and water. Plasticity index. The numerical difference between Quartzite, metamorphic. Rock consisting mainly of the liquid limit and the plastic limit. The range of quartz that formed through recrystallization of moisture content within which the soil remains quartz-rich sandstone or chert. plastic. Quartzite, sedimentary. Very hard but Playa. The generally dry and nearly level lake plain unmetamorphosed sandstone consisting chiefly that occupies the lowest parts of closed of quartz grains. depressional areas, such as those on Range condition. The present composition of the intermontane basin floors. Temporary flooding plant community on a range site in relation to the occurs primarily in response to precipitation and potential natural plant community for that site. runoff. (See Similarity index.) Plowpan. A compacted layer formed in the soil Range site. (See Ecological site.) directly below the plowed layer. Rangeland. Land on which the potential natural Ponding. Standing water on soils in closed vegetation is predominantly grasses, grasslike depressions. Unless the soils are artificially plants, forbs, or shrubs suitable for grazing or 340 Soil Survey

browsing. It includes natural grasslands, Regolith. The unconsolidated mantle of weathered savannas, many wetlands, some deserts, rock and soil material on the earth’s surface; the tundras, and areas that support certain forb and loose earth material above the solid rock. shrub communities. Relict stream terrace. One of a series of platforms Reaction, soil. A measure of acidity or alkalinity of a in or adjacent to a stream valley that formed prior soil, expressed in pH values. A soil that tests to to the current stream system. pH 7.0 is described as precisely neutral in Relief. The elevations or inequalities of a land reaction because it is neither acid nor alkaline. surface, considered collectively. The degrees of acidity or alkalinity, expressed as Residuum (residual soil material). Unconsolidated, pH values, are: weathered or partly weathered mineral material Ultra acid ...... less than 3.5 that accumulated as consolidated rock Extremely acid ...... 3.5 to 4.4 disintegrated in place. Very strongly acid ...... 4.5 to 5.0 Rill. A steep-sided channel resulting from accelerated Strongly acid ...... 5.1 to 5.5 erosion. A rill generally is a few inches deep and Moderately acid ...... 5.6 to 6.0 not wide enough to be an obstacle to farm Slightly acid ...... 6.1 to 6.5 machinery. Neutral ...... 6.6 to 7.3 Riser. The relatively short, steeply sloping area below Slightly alkaline ...... 7.4 to 7.8 a terrace tread that grades to a lower terrace Moderately alkaline ...... 7.9 to 8.4 tread or base level. Strongly alkaline ...... 8.5 to 9.0 Riverwash. Unstable areas of sandy, silty, clayey, or Very strongly alkaline ...... 9.1 and higher gravelly sediments. These areas are flooded, washed, and reworked by rivers so frequently Recessional moraine. A moraine formed during a that they support little or no vegetation. temporary but significant halt in the retreat of a Road cut. A sloping surface produced by mechanical glacier. means during road construction. It is commonly Red beds. Sedimentary strata that are mainly red on the uphill side of the road. and are made up largely of sandstone and shale. Rock fragments. Rock or mineral fragments having Redox concentrations. Nodules, concretions, soft a diameter of 2 millimeters or more; for example, masses, pore linings, and other features resulting boulders, stones, cobbles, and gravel. from the accumulation of iron or manganese Rock outcrop. Exposures of bare bedrock other than oxide. An indication of chemical reduction and lava flows and rock-lined pits. oxidation resulting from saturation. Root zone. The part of the soil that can be Redox depletions. Low-chroma zones from which penetrated by plant roots. iron and manganese oxide or a combination of Rubble land. Areas that have more than 90 percent iron and manganese oxide and clay has been of the surface covered by stones or boulders. removed. These zones are indications of the Voids contain no soil material and virtually no chemical reduction of iron resulting from vegetation other than lichens. The areas saturation. commonly are at the base of mountain slopes, Redox features. Redox concentrations, redox but some are on mountain slopes as deposits of depletions, reduced matrices, a positive reaction cobbles, stones, and boulders left by Pleistocene to alpha,alpha-dipyridyl, and other features glaciation or by periglacial phenomena. indicating the chemical reduction and oxidation of Runoff. The precipitation discharged into stream iron and manganese compounds resulting from channels from an area. The water that flows off saturation. the surface of the land without sinking into the Reduced matrix. A soil matrix that has low chroma in soil is called surface runoff. Water that enters the situ because of chemically reduced iron (Fe II). soil before reaching surface streams is called The chemical reduction results from nearly ground-water runoff or seepage flow from ground continuous wetness. The matrix undergoes a water. change in hue or chroma within 30 minutes after Saline soil. A soil containing soluble salts in an exposure to air as the iron is oxidized (Fe III). A amount that impairs growth of plants. A saline type of redox feature. soil does not contain excess exchangeable Regeneration. The new growth of a natural plant sodium. community, developing from seed. Sweet Grass County Area, Montana—Part I 341

Salinity. The electrical conductivity of a saline soil. It placed in water. The fragments are hard or very is expressed, in millimhos per centimeter, as hard when dry. Determining the texture by the follows: usual field method is difficult. Nonsaline ...... 0 to 4 Sequum. A sequence consisting of an illuvial horizon Slightly saline ...... 4 to 8 and the overlying eluvial horizon. (See Moderately saline ...... 8 to 16 Eluviation.) Strongly saline ...... more than 16 Series, soil. A group of soils that have profiles that are almost alike, except for differences in texture Sand. As a soil separate, individual rock or mineral of the surface layer or of the underlying material. fragments from 0.05 to 2.0 millimeters in All the soils of a series have horizons that are diameter. Most sand grains consist of quartz. As similar in composition, thickness, and a soil textural class, a soil that is 85 percent or arrangement. more sand and not more than 10 percent clay. Shale. Sedimentary rock formed by the hardening of Sandstone. Sedimentary rock containing dominantly a clay deposit. sand-sized particles. Shallow soil. A soil that is 10 to 20 inches deep over Sandy soil. Sand or loamy sand. bedrock or to other material that restricts the Sapric soil material (muck). The most highly penetration of plant roots. decomposed of all organic soil material. Muck Sheet erosion. The removal of a fairly uniform layer has the least amount of plant fiber, the highest of soil material from the land surface by the bulk density, and the lowest water content at action of rainfall and surface runoff. saturation of all organic soil material. Shelterwood system. A forest management system Saturation. Wetness characterized by zero or requiring the removal of a stand in a series of positive pressure of the soil water. Under cuts so that regeneration occurs under a partial conditions of saturation, the water will flow from canopy. After regeneration, a final cut removes the soil matrix into an unlined auger hole. the shelterwood and allows the stand to develop Sawlogs. Logs of suitable size and quality for the in the open as an even-aged stand. The system is production of lumber. well suited to sites where shelter is needed for Scarification. The act of abrading, scratching, regeneration, and it can aid regeneration of the loosening, crushing, or modifying the surface to more intolerant tree species in a stand. increase water absorption or to provide a more Shoulder. The uppermost inclined surface at the top tillable soil. of a hillside. It is the transitional zone from the Scribner’s log rule. A method of estimating the backslope to the summit of a hill or mountain. The number of board feet that can be cut from a log surface is dominantly convex in profile and of a given diameter and length. erosional in origin. Sedimentary plain. An extensive nearly level to Shrink-swell (in tables). The shrinking of soil when gently rolling or moderately sloping area that is dry and the swelling when wet. Shrinking and underlain by sedimentary bedrock and that has swelling can damage roads, dams, building a slope of 0 to 8 percent. foundations, and other structures. It can also Sedimentary rock. Rock made up of particles damage plant roots. deposited from suspension in water. The chief Side slope. A geomorphic component of hills kinds of sedimentary rock are conglomerate, consisting of a laterally planar area of a hillside. formed from gravel; sandstone, formed from The overland waterflow is predominantly parallel. sand; shale, formed from clay; and limestone, Silica. A combination of silicon and oxygen. The formed from soft masses of calcium carbonate. mineral form is called quartz. There are many intermediate types. Some wind- Silt. As a soil separate, individual mineral particles deposited sand is consolidated into sandstone. that range in diameter from the upper limit of clay Sedimentary uplands. Land areas of bedrock (0.002 millimeters) to the lower limit of very fine formed from water- or wind-deposited sediments. sand (0.05 millimeters). As a soil textural class, They are higher on the landscape than the flood soil that is 80 percent or more silt and less than plain. 12 percent clay. Seepage (in tables). The movement of water through Siltstone. Sedimentary rock made up of dominantly soil. Seepage adversely affects the specified use. silt-sized particles. Semiconsolidated sedimentary beds. Soft geologic Similar soils. Soils that share limits of diagnostic sediments that disperse when fragments are criteria, behave and perform in a similar manner, 342 Soil Survey

and have similar conservation needs or or clayey, is slippery when wet, and is low in management requirements for the major land productivity. uses in the survey area. Slope. The inclination of the land surface from the Similarity index. A similarity index is the percentage horizontal. Percentage of slope is the vertical of a specific vegetation state plant community distance divided by horizontal distance, then that is presently on the site. multiplied by 100. Thus, a slope of 20 percent is a Sinkhole. A depression in the landscape where drop of 20 feet in 100 feet of horizontal distance. limestone has been dissolved. In this survey the following slope classes are Site class. A grouping of site indexes into five to recognized: seven production capability levels. Each level can Nearly level ...... 0 to 2 percent be represented by a site curve. Gently sloping ...... 2 to 4 percent Site curve (50-year). A set of related curves on a Moderately sloping ...... 4 to 8 percent graph that shows the average height of dominant Strongly sloping ...... 8 to 15 percent or dominant and codominant trees for the range Moderately steep ...... 15 to 25 percent of ages on soils that differ in productivity. Each Steep ...... 25 to 45 percent level is represented by a curve. The basis of the Very steep ...... more than 45 percent curves is the height of dominant or dominant and codominant trees that are 50 years old or are Slope (in tables). Slope is great enough that special 50 years old at breast height. practices are required to ensure satisfactory Site curve (100-year). A set of related curves on a performance of the soil for a specific use. graph that shows the average height of dominant Slow intake (in tables). The slow movement of water or dominant and codominant trees for a range of into the soil. ages on soils that differ in productivity. Each level Sodic (alkali) soil. A soil having so high a degree is represented by a curve. The basis of the curves of alkalinity (pH 8.5 or higher) or so high a is the height of dominant or dominant and percentage of exchangeable sodium (15 percent codominant trees that are 100 years old or are or more of the total exchangeable bases), or 100 years old at breast height. both, that plant growth is restricted. Site index. A designation of the quality of a forest site Sodicity. The degree to which a soil is affected by based on the height of the dominant stand at an exchangeable sodium. Sodicity is expressed as a arbitrarily chosen age. For example, if the sodium adsorption ratio (SAR) of a saturation average height attained by dominant or dominant extract, or the ratio of Na+ to Ca++ + Mg++. The and codominant trees in a fully stocked stand at degrees of sodicity and their respective ratios the age of 50 years is 75 feet, the site index is 75. are: Skid trails. Pathways along which logs are dragged Slight ...... less than 13:1 to a common site for loading onto a logging truck. Moderate ...... 13-30:1 Slash. The branches, bark, treetops, reject logs, and Strong ...... more than 30:1 broken or uprooted trees left on the ground after logging. Sodium adsorption ratio (SAR). A measure of the Slickens. Accumulations of fine textured material, amount of sodium (Na) relative to calcium (Ca) such as material separated in placer-mine and and magnesium (Mg) in the water extract from ore-mill operations. Slickens from ore mills saturated soil paste. It is the ratio of the Na commonly consist of freshly ground rock that has concentration divided by the square root of one- undergone chemical treatment during the milling half of the Ca + Mg concentration. process. Soft bedrock. Bedrock that can be excavated with Slickensides. Polished and grooved surfaces trenching machines, backhoes, small rippers, and produced by one mass sliding past another. In other equipment commonly used in construction. soils, slickensides may occur at the bases of slip Soil. A natural, three-dimensional body at the earth’s surfaces on the steeper slopes; on faces of surface. It is capable of supporting plants and has blocks, prisms, and columns; and in swelling properties resulting from the integrated effect of clayey soils, where there is marked change in climate and living matter acting on earthy parent moisture content. material, as conditioned by relief over periods of Slickspot. A small area of soil having a puddled, time. crusted, or smooth surface and an excess of Soil separates. Mineral particles less than exchangeable sodium. The soil generally is loamy 2 millimeters in equivalent diameter and ranging Sweet Grass County Area, Montana—Part I 343

between specified size limits. The names and streambed, or valley floor that were produced sizes, in millimeters, of separates recognized in during a former stage of erosion or deposition. the United States are as follows: Stripcropping. Growing crops in a systematic Very coarse sand ...... 2.0 to 1.0 arrangement of strips or bands that provide Coarse sand ...... 1.0 to 0.5 vegetative barriers to soil blowing and water Medium sand ...... 0.5 to 0.25 erosion. Fine sand ...... 0.25 to 0.10 Structure, soil. The arrangement of primary soil Very fine sand ...... 0.10 to 0.05 particles into compound particles or aggregates. Silt ...... 0.05 to 0.002 The principal forms of soil structure are platy Clay ...... less than 0.002 (laminated), prismatic (vertical axis of aggregates longer than horizontal), columnar (prisms with Solum. The upper part of a soil profile, above the rounded tops), blocky (angular or subangular), C horizon, in which the processes of soil and granular. Structureless soils are either single formation are active. The solum in soil consists grain (each grain by itself, as in dune sand) or of the A, E, and B horizons. Generally, the massive (the particles adhering without any characteristics of the material in these horizons regular cleavage, as in many hardpans). are unlike those of the material below the solum. Stubble mulch. Stubble or other crop residue left on The living roots and plant and animal activities the soil or partly worked into the soil. It protects are largely confined to the solum. the soil from wind erosion and water erosion after Species. A single, distinct kind of plant or animal harvest, during preparation of a seedbed for the having certain distinguishing characteristics. next crop, and during the early growing period of Stone line. A concentration of coarse fragments in a the new crop. soil. Generally, it is indicative of an old weathered Subsoil. Technically, the B horizon; roughly, the part surface. In a cross section, the line may be one of the solum below plow depth. fragment or more thick. It generally overlies Subsoiling. Tilling a soil below normal plow depth, material that weathered in place and is overlain ordinarily to shatter or loosen a layer that is by recent sediment of variable thickness. restrictive to roots. Stones. Rock fragments 10 to 24 inches (25 to Substratum. The part of the soil below the solum. 60 centimeters) in diameter if rounded or 15 to Subsurface layer. Any surface soil horizon (A, E, AB, 24 inches (38 to 60 centimeters) in length if or EB) below the surface layer. flat. Summer fallow. The tillage of uncropped land during Stony. Refers to a soil containing stones in numbers the summer to control weeds and allow storage that interfere with tillage, or stones cover .01 to of moisture in the soil for the growth of a later 0.1 percent of the surface. Very stony means crop. A practice common in semiarid regions, that 0.1 to 3.0 percent of the surface is covered where annual precipitation is not enough to with stones. Extremely stony means that 3 to produce a crop every year. Summer fallow is 15 percent of the surface is covered with stones. frequently practiced before planting winter grain. Stony soil material. Soil that is 15 to 35 percent, by Summit. A general term for the top, or highest level, volume, rock fragments that are dominated by of an upland feature, such as a hill or mountain. It fragments 10 to 24 inches (25 to 60 centimeters) commonly refers to a higher area that has a in diameter. gentle slope and is flanked by steeper slopes. Strath terrace. A surface cut formed by the erosion Surface layer. The soil ordinarily moved in tillage, or of hard or semiconsolidated bedrock and thinly its equivalent in uncultivated soil, ranging in mantled with stream deposits. depth from 4 to 10 inches (10 to 25 centimeters). Stream channel. The hollow bed where a natural Frequently designated as the “plow layer,” or the stream of surface water flows or may flow; the “Ap horizon.” deepest or central part of the bed, formed by the Tailwater. The water directly downstream of a main current and covered more or less structure. continuously by water. Talus. Rock fragments of any size or shape, Stream terrace. One of a series of platforms in a commonly coarse and angular, derived from and stream valley, flanking and more or less parallel lying at the base of a cliff or very steep rock to the stream channel. It originally formed near slope. The accumulated mass of such loose, the level of the stream and is the dissected broken rock formed chiefly by falling, rolling, or remnants of an abandoned flood plain, sliding. 344 Soil Survey

Taxadjuncts. Soils that cannot be classified in a Trafficability. The degree to which a soil is capable series recognized in the classification system. of supporting vehicular traffic across a wide Such soils are named for a series they strongly range in soil moisture conditions. resemble and are designated as taxadjuncts to Tread. The relatively flat terrace surface that was cut that series because they differ in ways too small or built by stream or wave action. to be of consequence in interpreting their use Tuff. A compacted deposit that is 50 percent or more and behavior. volcanic ash and dust. Terminal moraine. A belt of thick glacial drift that Understory. Any plants in a forest community that generally marks the termination of important grow to a height of less than 5 feet. glacial advances. Upland. Land at a higher elevation, in general, than Terrace. An embankment, or ridge, constructed the alluvial plain or stream terrace; land above across sloping soils on the contour or at a slight the lowlands along streams. angle to the contour. The terrace intercepts Valley. An elongated depressional area primarily surface runoff so that water soaks into the soil or developed by stream action. flows slowly to a prepared outlet. A terrace in a Valley fill. In glaciated regions, material deposited in field generally is built so that the field can be stream valleys by glacial meltwater. In farmed. A terrace intended mainly for drainage nonglaciated regions, alluvium deposited by has a deep channel that is maintained in heavily loaded streams. permanent sod. Variegation. Refers to patterns of contrasting colors Terrace (geologic). An old alluvial plain, ordinarily assumed to be inherited from the parent material flat or undulating, bordering a river, a lake, or the rather than to be the result of poor drainage. sea. Varve. A sedimentary layer or a lamina or sequence Terracette. Small, irregular step-like forms on steep of laminae deposited in a body of still water within hillslopes, especially in pasture, formed by creep a year. Specifically, a thin pair of graded or erosion of surficial materials that may or may glaciolacustrine layers seasonally deposited, not be induced by trampling of livestock such as usually by meltwater streams, in a glacial lake or sheep or cattle. other body of still water in front of a glacier. Texture, soil. The relative proportions of sand, silt, Very deep soil. A soil that is more than 60 inches and clay particles in a mass of soil. The basic deep over bedrock or to other material that textural classes, in order of increasing proportion restricts the penetration of plant roots. of fine particles, are sand, loamy sand, sandy Very shallow soil. A soil that is less than 10 inches loam, loam, silt loam, silt, sandy clay loam, clay deep over bedrock or to other material that loam, silty clay loam, sandy clay, silty clay, and restricts the penetration of plant roots. clay. The sand, loamy sand, and sandy loam Water bars. Smooth, shallow ditches or depressional classes may be further divided by specifying areas that are excavated at an angle across a “coarse,” “fine,” or “very fine.” sloping road. They are used to reduce the Till plain. An extensive, nearly level to gently rolling downward velocity of water and divert it off and or moderately sloping area that is underlain by or away from the road surface. Water bars can consists of till and that has a slope of 0 to 8 easily be driven over if constructed properly. percent. Water-spreading. Diverting runoff from natural Tilth, soil. The physical condition of the soil as channels by means of a system of dams, dikes, related to tillage, seedbed preparation, seedling or ditches and spreading it over relatively flat emergence, and root penetration. surfaces. Toeslope. The outermost inclined surface at the base Weathering. All physical and chemical changes of a hill. Toeslopes are commonly gentle and produced in rocks or other deposits at or near linear in profile. the earth’s surface by atmospheric agents. These Topsoil. The upper part of the soil, which is the most changes result in disintegration and favorable material for plant growth. It is ordinarily decomposition of the material. rich in organic matter and is used to topdress Well graded. Refers to soil material consisting of roadbanks, lawns, and land affected by mining. coarse-grained particles that are well distributed Trace elements. Chemical elements, for example, over wide range in size or diameter. Such soil zinc, cobalt, manganese, copper, and iron, in normally can be easily increased in density and soils in extremely small amounts. They are bearing properties by compaction. Contrasts with essential to plant growth. poorly graded soil. Sweet Grass County Area, Montana—Part I 345

Wilting point (or permanent wilting point). The Windthrow. The action of uprooting and tipping over moisture content of soil, on an ovendry basis, at trees by the wind. which a plant (specifically a sunflower) wilts so much that it does not recover when placed in a humid, dark chamber. Accessibility Statement

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