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 has leadership for the Federal part of the National Cooperative Soil Survey. Major fieldwork for this soil survey was completed in 1990. Soil names and descriptions were approved in 1992. Unless otherwise indicated, statements in this publication refer to conditions in the survey area in 1991. This survey was made cooperatively by the United States Department of Agriculture, Natural Resources Conservation Service and Forest Service; United States Department of the Interior, Bureau of Land Management; and the Montana Agricultural Experiment Station. It is part of the technical assistance furnished to the Carter 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: Archin soils are in the foreground with the Long Pines in the background.

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 75A—Archin-Absher complex, 0 to 2 percent slopes ...... 31 How To Use This Soil Survey ...... i 75C—Archin-Absher complex, 2 to 8 percent Index to Taxonomic Units ...... x slopes ...... 32 Index to Map Units ...... xi 175A—Archin loam, 0 to 2 percent slopes ...... 33 Summary of Tables ...... xvi 175C—Archin loam, 2 to 8 percent slopes ...... 33 Foreword ...... xix 275D—Archin, gullied-Delpoint complex, General Nature of the Survey Area...... 1 4 to 15 percent slopes ...... 33 History...... 1 375C—Archin-Ynot complex, 2 to 8 percent Industry and Recreation ...... 2 slopes ...... 34 Physiography and Drainage...... 2 Arsite Series ...... 34 Geology ...... 2 79C—Arsite clay, 0 to 8 percent slopes ...... 35 Mineral Resources ...... 4 179E—Arsite-Rock outcrop complex, 8 to 25 Ground-water Resources...... 5 percent slopes ...... 35 Climate...... 6 Assinniboine Series ...... 36 How This Survey Was Made ...... 6 74A—Assinniboine sandy clay loam, 0 to 2 Formation and Classification of the Soils ...... 13 percent slopes ...... 37 Formation of the Soils ...... 13 74C—Assinniboine sandy clay loam, 2 to 8 Climate ...... 13 percent slopes ...... 37 Living Organisms ...... 13 174C—Assinniboine-Ynot complex, 2 to 8 Topography ...... 13 percent slopes ...... 38 Parent Material ...... 14 13F—Badland ...... 38 Time...... 14 Bascovy Series ...... 38 Classification of the Soils ...... 14 90C—Bascovy clay, 2 to 8 percent slopes...... 39 Soil Series and Detailed Soil Map Units ...... 23 90D—Bascovy clay, 8 to 15 percent slopes...... 40 Abor Series ...... 24 490C—Bascovy-Ethridge complex, 2 to 8 51C—Abor silty clay loam, 2 to 8 percent percent slopes ...... 40 slopes ...... 25 590C—Bascovy-Marvan complex, 2 to 8 251D—Abor-Yawdim silty clay loams, 4 to 15 percent slopes ...... 40 percent slopes ...... 25 623D—Bascovy clay, warm, 0 to 9 percent Absher Series ...... 26 slopes ...... 41 168B—Absher-Gerdrum complex, 0 to 4 633D—Bascovy-Neldore clays, warm, 6 to 21 percent slopes ...... 27 percent slopes ...... 41 Alona Series ...... 27 Beaverflat Series ...... 42 20C—Alona silt loam, 2 to 8 percent slopes ...... 28 30A—Beaverflat loam, 0 to 4 percent 621C—Alona silt loam, warm, 2 to 8 percent slopes ...... 43 slopes ...... 29 130A—Beaverflat sandy loam, 0 to 4 percent Alzada Series ...... 29 slopes ...... 43 92C—Alzada clay loam, 2 to 8 percent Beenom Series ...... 43 slopes ...... 30 49A—Beenom-Reeder loams, 1 to 4 percent Archin Series ...... 30 slopes ...... 44 iv

116C—Beenom-Parchin complex, 2 to 8 170D—Busby-Blacksheep-Twilight fine sandy percent slopes ...... 45 loams, 8 to 25 percent slopes ...... 60 Belltower Series ...... 45 170E—Busby-Blacksheep-Rock outcrop 144D—Belltower-Reeder-Vebar complex, complex, 8 to 25 percent slopes...... 60 4 to 15 percent slopes ...... 46 270E—Busby, gullied-Delpoint-Yawdim 144E—Belltower-Dast-Reeder complex, complex, 8 to 25 percent slopes...... 61 15 to 35 percent slopes ...... 47 Cabba Series ...... 62 144F—Belltower-Dast complex, 35 to 60 112D—Cabba silt loam, 8 to 15 percent percent slopes ...... 48 slopes ...... 62 Bickerdyke Series ...... 48 212E—Cabba-Rock outcrop complex, 87A—Bickerdyke clay, 0 to 2 percent slopes ..... 49 15 to 45 percent slopes ...... 63 87C—Bickerdyke clay, 2 to 8 percent slopes..... 49 312D—Cabba-Dast complex, 8 to 15 percent Blacksheep Series ...... 50 slopes ...... 63 55D—Blacksheep-Twilight fine sandy loams, Cabbart Series ...... 64 8 to 15 percent slopes ...... 50 60D—Cabbart silt loam, 4 to 15 percent 55E—Blacksheep-Twilight fine sandy loams, slopes ...... 64 15 to 45 percent slopes ...... 51 160E—Cabbart-Rock outcrop-Delpoint 155E—Blacksheep-Rock outcrop complex, complex, 15 to 50 percent slopes...... 65 25 to 50 percent slopes ...... 51 160F—Cabbart-Rock outcrop-Yawdim Bonfri Series ...... 52 complex, 15 to 70 percent slopes...... 65 91C—Bonfri loam, 2 to 8 percent slopes ...... 53 260D—Cabbart-Cambeth silt loams, 8 to 15 91D—Bonfri loam, 8 to 15 percent slopes ...... 53 percent slopes ...... 66 191C—Bonfri-Cambeth complex, 2 to 8 360D—Cabbart-Bascovy complex, 4 to 15 percent slopes ...... 53 percent slopes ...... 66 291D—Bonfri-Cabbart loams, 8 to 15 percent Cambeth Series ...... 67 slopes ...... 54 160D—Cambeth-Yamacall complex, 8 to 15 391C—Bonfri-Parchin complex, 2 to 8 percent percent slopes ...... 68 slopes ...... 55 260C—Cambeth-Cabbart silt loams, 2 to 8 Broadus Series ...... 55 percent slopes ...... 68 126D—Broadus-Ridge-Reeder complex, 260E—Cambeth-Cabbart-Yawdim complex, 8 to 25 percent slopes ...... 56 15 to 25 percent slopes ...... 69 126F—Broadus-Ridge-Rock outcrop complex, Carfall Series ...... 69 25 to 65 percent slopes ...... 57 14C—Carfall loam, 2 to 8 percent slopes ...... 70 Bullock Series ...... 57 114C—Carfall-Assinniboine complex, 2 to 8 Busby Series ...... 58 percent slopes ...... 70 70C—Busby fine sandy loam, 2 to 8 percent 114D—Carfall-Assinniboine complex, 8 to 15 slopes ...... 59 percent slopes ...... 71 70D—Busby fine sandy loam, 8 to 15 percent 214C—Carfall fine sandy loam, 2 to 8 percent slopes ...... 59 slopes ...... 71 v

214D—Carfall fine sandy loam, 8 to 15 271D—Delpoint-Yamacall loams, 8 to 15 percent slopes ...... 72 percent slopes ...... 86 Chinook Series ...... 72 DA—Denied access ...... 86 83A—Chinook sandy loam, 0 to 2 percent Eapa Series ...... 86 slopes ...... 73 84A—Eapa loam, 0 to 2 percent slopes ...... 87 83C—Chinook sandy loam, 2 to 8 percent 84C—Eapa loam, 2 to 8 percent slopes ...... 88 slopes ...... 73 84D—Eapa loam, 8 to 15 percent slopes ...... 88 83D—Chinook sandy loam, 8 to 15 percent 167C—Eapa-Yamacall loams, 2 to 8 percent slopes ...... 74 slopes ...... 88 183C—Chinook-Assinniboine complex, 2 to 8 184C—Eapa-Archin loams, 2 to 8 percent percent slopes ...... 74 slopes ...... 89 283C—Chinook-Archin complex, 2 to 8 603C—Eapa loam, warm, 1 to 6 percent percent slopes ...... 75 slopes ...... 89 Cohagen Series ...... 75 Ethridge Series ...... 90 Creed Series ...... 76 66C—Ethridge silty clay loam, 2 to 8 percent 54A—Creed loam, 0 to 2 percent slopes ...... 77 slopes ...... 91 54C—Creed loam, 2 to 8 percent slopes ...... 77 85A—Ethridge loam, 0 to 2 percent slopes ...... 91 154C—Creed-Absher complex, 2 to 8 percent 85C—Ethridge loam, 2 to 8 percent slopes ...... 91 slopes ...... 78 185A—Ethridge-Daglum complex, 0 to 4 254C—Creed-Gerdrum complex, 2 to 8 percent slopes ...... 92 percent slopes ...... 78 626C—Ethridge silty clay loam, warm, 2 to 8 602C—Creed-Gerdrum complex, warm, 2 to 6 percent slopes ...... 92 percent slopes ...... 79 Gerdrum Series ...... 93 Daglum Series ...... 79 65A—Gerdrum clay loam, 0 to 2 percent 45B—Daglum loam, 0 to 4 percent slopes ...... 80 slopes ...... 94 Dast Series ...... 80 65C—Gerdrum clay loam, 2 to 8 percent 125F—Dast-Ridge-Rock outcrop complex, slopes ...... 94 35 to 60 percent slopes ...... 81 165A—Gerdrum-Absher complex, 0 to 2 225E—Dast-Vebar complex, 15 to 35 percent percent slopes ...... 95 slopes ...... 82 165C—Gerdrum-Absher complex, 2 to 8 225F—Dast-Vebar complex, 35 to 60 percent percent slopes ...... 95 slopes ...... 82 611B—Gerdrum-Absher complex, warm, 325E—Dast-Cabba-Mowbray complex, 0 to 3 percent slopes ...... 96 15 to 35 percent slopes ...... 83 611D—Gerdrum-Absher complex, warm, Delpoint Series ...... 84 3 to 9 percent slopes ...... 96 71C—Delpoint loam, 2 to 8 percent slopes ...... 84 Glendive Series ...... 97 171C—Delpoint-Cabbart complex, 2 to 8 61A—Glendive sandy loam, 0 to 2 percent percent slopes ...... 85 slopes ...... 98 171D—Delpoint-Cabbart complex, 8 to 15 161B—Glendive sandy loam, saline, 0 to 4 percent slopes ...... 85 percent slopes ...... 98 vi

Hanly Series ...... 98 Marmarth Series ...... 113 7B—Hanly-Ryell fine sandy loams, 0 to 4 81C—Marmarth loam, 2 to 8 percent percent slopes ...... 99 slopes ...... 114 Haploborolls ...... 99 629C—Marmarth loam, warm, 2 to 8 percent Harlake Series ...... 100 slopes ...... 114 57A—Harlake silty clay, saline, 0 to 2 percent Marvan Series ...... 114 slopes ...... 101 89A—Marvan silty clay, 0 to 2 percent 157A—Harlake silty clay loam, 0 to 2 percent slopes ...... 116 slopes ...... 101 89C—Marvan silty clay, 2 to 8 percent 606B—Harlake silty clay loam, warm, saline, slopes ...... 116 0 to 3 percent slopes ...... 102 613B—Marvan-Vanda clays, warm, 0 to 3 608B—Harlake clay, warm, 0 to 3 percent percent slopes ...... 116 slopes ...... 102 614C—Marvan clay, warm, 0 to 6 percent Havre Series ...... 103 slopes ...... 117 56A—Havre loam, 0 to 2 percent slopes ...... 103 635C—Marvan-Bascovy clays, warm, 0 to 6 156A—Havre loam, saline, 0 to 2 percent percent slopes ...... 117 slopes ...... 104 M-W—Miscellaneous water ...... 118 256A—Havre-Harlake complex, 0 to 2 percent Mowbray Series ...... 118 slopes ...... 104 152F—Mowbray-Cabba-Vebar complex, Julin Series ...... 105 35 to 60 percent slopes ...... 119 Kirby Series ...... 105 Moyerson Series ...... 119 176D—Kirby-Cabbart complex, 8 to 25 77D—Moyerson silty clay loam, 4 to 15 percent slopes ...... 106 percent slopes ...... 120 276F—Kirby-Blacksheep-Rock outcrop 277D—Moyerson-Orinoco silty clay loams, complex, 25 to 60 percent slopes...... 107 4 to 15 percent slopes ...... 121 Kobase Series ...... 107 477E—Moyerson silty clay loam, 15 to 35 78A—Kobase silty clay loam, 0 to 2 percent percent slopes ...... 121 slopes ...... 108 605E—Moyerson, warm-Rock outcrop 78C—Kobase silty clay loam, 2 to 8 percent complex, 9 to 45 percent slopes...... 121 slopes ...... 109 Neldore Series ...... 122 Kremlin Series ...... 109 58D—Neldore-Rock outcrop complex, 72A—Kremlin loam, 0 to 2 percent slopes ...... 110 4 to 15 percent slopes ...... 123 72C—Kremlin loam, 2 to 8 percent slopes ...... 110 58E—Neldore-Rock outcrop complex, 172C—Kremlin-Cabbart complex, 2 to 8 15 to 45 percent slopes ...... 123 percent slopes ...... 111 158D—Neldore clay, 4 to 15 percent Marias Series ...... 111 slopes ...... 123 94A—Marias silty clay loam, 0 to 2 percent 158E—Neldore clay, 15 to 35 percent slopes ...... 112 slopes ...... 124 94C—Marias silty clay loam, 2 to 8 percent 258D—Neldore-Volborg clays, 4 to 15 percent slopes ...... 113 slopes ...... 124 vii

358D—Neldore-Bascovy clays, 4 to 15 percent 13E—Rock outcrop ...... 139 slopes ...... 125 177E—Rock outcrop-Moyerson complex, 625E—Neldore clay, warm, 3 to 25 percent 15 to 50 percent slopes ...... 139 slopes ...... 125 Ryell Series...... 139 Noonan Series ...... 126 Shambo Series ...... 140 Orinoco Series ...... 127 131C—Shambo-Noonan loams, 4 to 15 53C—Orinoco silty clay loam, 2 to 8 percent percent slopes ...... 141 slopes ...... 127 231D—Shambo-Mowbray-Parchin complex, 153D—Orinoco-Yawdim silty clay loams, 4 to 25 percent slopes ...... 142 4 to 15 percent slopes ...... 128 Tanna Series ...... 142 253D—Orinoco-Weingart complex, 4 to 15 64C—Tanna silty clay loam, 2 to 8 percent percent slopes ...... 128 slopes ...... 143 631D—Orinoco-Yawdim silty clay loams, 164C—Tanna-Ethridge silty clay loams, 2 to 8 warm, 4 to 15 percent slopes ...... 129 percent slopes ...... 143 Parchin Series ...... 129 164D—Tanna-Ethridge silty clay loams, 21C—Parchin fine sandy loam, 2 to 8 percent 8 to 15 percent slopes ...... 144 slopes ...... 131 Teigen Series ...... 144 121C—Parchin-Bullock complex, 2 to 8 95A—Teigen silty clay loam, 0 to 4 percent percent slopes ...... 131 slopes ...... 145 Parshall Series ...... 131 95D—Teigen clay loam, gullied, 4 to 15 36A—Parshall sandy loam, 0 to 4 percent percent slopes ...... 146 slopes ...... 132 Tricart Series ...... 146 36D—Parshall fine sandy loam, 4 to 15 23D—Tricart clay loam, 4 to 15 percent percent slopes ...... 133 slopes ...... 147 136D—Parshall-Cohagen fine sandy loams, 23E—Tricart gravelly loam, 15 to 45 percent 4 to 15 percent slopes ...... 133 slopes ...... 147 Prego Series ...... 134 Twilight Series ...... 148 48D—Prego sandy loam, 2 to 15 percent 69C—Twilight fine sandy loam, 2 to 8 percent slopes ...... 134 slopes ...... 148 Reeder Series ...... 135 69D—Twilight fine sandy loam, 8 to 15 42C—Reeder loam, 2 to 8 percent slopes ...... 136 percent slopes ...... 149 142D—Reeder-Cabba loams, 4 to 15 percent 269C—Twilight-Bonfri complex, 2 to 8 percent slopes ...... 136 slopes ...... 149 242D—Reeder-Dast complex, 4 to 15 percent 269D—Twilight-Bonfri complex, 8 to 15 slopes ...... 136 percent slopes ...... 150 Rentsac Series ...... 137 369C—Twilight-Delpoint complex, 2 to 8 99F—Rentsac-Twilight-Rock outcrop complex, percent slopes ...... 150 15 to 45 percent slopes ...... 138 369D—Twilight-Cabbart complex, 8 to 15 Ridge Series ...... 138 percent slopes ...... 151 viii

Ustochrepts...... 151 86C—Yamacall loam, 2 to 8 percent slopes .... 166 17E—Ustochrepts-Haploborolls complex, 86D—Yamacall loam, 8 to 15 percent slump, 15 to 45 percent slopes ...... 152 slopes ...... 166 Vaeda Series ...... 153 186A—Yamacall-Havre loams, 0 to 2 percent 96A—Vaeda silty clay loam, 0 to 2 percent slopes ...... 167 slopes ...... 154 186C—Yamacall-Havre loams, 2 to 8 percent 196C—Vaeda-Creed complex, 0 to 4 percent slopes ...... 167 slopes ...... 154 193C—Yamacall-Cambeth complex, 2 to 8 Vanda Series ...... 154 percent slopes ...... 168 97A—Vanda silty clay loam, 0 to 2 percent 286C—Yamacall-Delpoint loams, 2 to 8 slopes ...... 155 percent slopes ...... 168 197A—Vanda-Marvan complex, 0 to 2 386E—Yamacall-Cabbart loams, 15 to 35 percent slopes ...... 155 percent slopes ...... 169 197C—Vanda-Marvan complex, 2 to 8 586D—Yamacall-Delpoint-Cabbart loams, percent slopes ...... 156 8 to 15 percent slopes ...... 169 Varney Series ...... 156 Yawdim Series ...... 170 22A—Varney loam, 0 to 2 percent slopes ...... 158 162D—Yawdim silty clay loam, 4 to 15 percent 22C—Varney loam, 2 to 8 percent slopes ...... 158 slopes ...... 170 122C—Varney-Gerdrum complex, 2 to 8 262E—Yawdim-Blacksheep-Rock outcrop percent slopes ...... 158 complex, 15 to 45 percent slopes...... 171 Vebar Series ...... 159 Yegen Series ...... 171 Volborg Series ...... 160 41C—Yegen loam, 2 to 8 percent slopes ...... 172 98C—Volborg clay, 2 to 8 percent slopes ...... 160 41D—Yegen loam, 8 to 15 percent slopes ...... 172 198D—Volborg silty clay, saline, 4 to 15 141C—Yegen-Rentsac complex, 2 to 8 percent slopes ...... 161 percent slopes ...... 173 298E—Volborg-Julin-Rock outcrop complex, Ynot Series ...... 173 8 to 25 percent slopes ...... 161 59C—Ynot sandy loam, 2 to 8 percent 398E—Volborg-Volborg, saline-Rock outcrop slopes ...... 174 complex, 8 to 45 percent slopes...... 162 59D—Ynot sandy loam, 8 to 15 percent 634E—Volborg-Julin complex, warm, 6 to 60 slopes ...... 174 percent slopes ...... 162 Zatoville Series ...... 175 W—Water ...... 163 178C—Zatoville silty clay loam, 2 to 8 percent Weingart Series ...... 163 slopes ...... 176 15C—Weingart silty clay, 2 to 8 percent Zeona Series ...... 176 slopes ...... 164 119D—Zeona-Blacksheep-Rock outcrop 620C—Weingart silty clay loam, warm, 0 to 6 complex, 4 to 15 percent slopes...... 177 percent slopes ...... 164 References ...... 179 Yamacall Series ...... 165 Glossary ...... 181 86A—Yamacall loam, 0 to 2 percent slopes .... 166 ix

Part II Main Forest Access Road Limitations and Hazards ...... 137 How To Use This Soil Survey ...... i Forestland of Carter County ...... 138 Detailed Soil Map Unit Legend ...... iv Recreation...... 147 Summary of Tables ...... ix Wildlife Habitat ...... 171 Agronomy ...... 9 Elements of Wildlife Habitat ...... 171 Cropland Limitations and Hazards ...... 9 Kinds of Wildlife Habitat ...... 171 Crop Yield Estimates...... 10 Wildlife of Carter County ...... 172 Pasture and Hayland Management ...... 11 Engineering ...... 173 Land Capability Classification...... 11 Building Site Development ...... 173 Prime Farmland and Other Important Sanitary Facilities ...... 174 Farmland ...... 12 Waste Management ...... 175 Erosion Factors ...... 13 Construction Materials ...... 176 Windbreaks and Environmental Plantings ...... 14 Water Management ...... 177 Range ...... 77 Soil Properties ...... 273 Similarity Index ...... 78 Engineering Index Properties ...... 273 Rangeland Management ...... 78 Physical and Chemical Properties ...... 274 Understory Management ...... 79 Water Features ...... 276 Forestland ...... 135 Soil Features ...... 277 Woodland Ordination System ...... 135 References ...... 411 Forestland Management and Productivity ...... 136 Glossary ...... 413

Issued 2003 x

Index to Taxonomic Units

Abor Series ...... 24 Kirby Series ...... 105 Absher Series ...... 26 Kobase Series ...... 107 Alona Series ...... 27 Kremlin Series ...... 109 Alzada Series ...... 29 Marias Series ...... 111 Archin Series ...... 30 Marmarth Series ...... 113 Arsite Series ...... 34 Marvan Series ...... 114 Assinniboine Series ...... 36 Mowbray Series ...... 118 Bascovy Series ...... 38 Moyerson Series ...... 119 Beaverflat Series ...... 42 Neldore Series ...... 122 Beenom Series ...... 43 Noonan Series ...... 126 Belltower Series ...... 45 Orinoco Series ...... 127 Bickerdyke Series ...... 48 Parchin Series ...... 129 Blacksheep Series ...... 50 Parshall Series ...... 131 Bonfri Series ...... 52 Prego Series ...... 134 Broadus Series ...... 55 Reeder Series ...... 135 Bullock Series ...... 57 Rentsac Series ...... 137 Busby Series ...... 58 Ridge Series ...... 138 Cabba Series ...... 62 Ryell Series...... 139 Cabbart Series ...... 64 Shambo Series ...... 140 Cambeth Series ...... 67 Tanna Series ...... 142 Carfall Series ...... 69 Teigen Series ...... 144 Chinook Series ...... 72 Tricart Series ...... 146 Cohagen Series ...... 75 Twilight Series ...... 148 Creed Series ...... 76 Ustochrepts...... 151 Daglum Series ...... 79 Vaeda Series ...... 153 Dast Series ...... 80 Vanda Series ...... 154 Delpoint Series ...... 84 Varney Series ...... 156 Eapa Series ...... 86 Vebar Series ...... 159 Ethridge Series ...... 90 Volborg Series ...... 160 Gerdrum Series ...... 93 Weingart Series ...... 163 Glendive Series ...... 97 Yamacall Series ...... 165 Hanly Series ...... 98 Yawdim Series ...... 170 Haploborolls ...... 99 Yegen Series ...... 171 Harlake Series ...... 100 Ynot Series ...... 173 Havre Series ...... 103 Zatoville Series ...... 175 Julin Series ...... 105 Zeona Series ...... 176 xi

Index to Map Units

7B—Hanly-Ryell fine sandy loams, 0 to 4 55E—Blacksheep-Twilight fine sandy loams, percent slopes ...... 99 15 to 45 percent slopes ...... 51 13E—Rock outcrop ...... 139 56A—Havre loam, 0 to 2 percent slopes ...... 103 13F—Badland...... 38 57A—Harlake silty clay, saline, 0 to 2 percent 14C—Carfall loam, 2 to 8 percent slopes ...... 70 slopes ...... 101 15C—Weingart silty clay, 2 to 8 percent 58D—Neldore-Rock outcrop complex, 4 to 15 slopes ...... 164 percent slopes ...... 123 17E—Ustochrepts-Haploborolls complex, 58E—Neldore-Rock outcrop complex, 15 to 45 slump, 15 to 45 percent slopes ...... 152 percent slopes ...... 123 20C—Alona silt loam, 2 to 8 percent slopes ..... 28 59C—Ynot sandy loam, 2 to 8 percent 21C—Parchin fine sandy loam, 2 to 8 percent slopes ...... 174 slopes ...... 131 59D—Ynot sandy loam, 8 to 15 percent 22A—Varney loam, 0 to 2 percent slopes ...... 158 slopes ...... 174 22C—Varney loam, 2 to 8 percent slopes ...... 158 60D—Cabbart silt loam, 4 to 15 percent 23D—Tricart clay loam, 4 to 15 percent slopes ...... 64 slopes ...... 147 61A—Glendive sandy loam, 0 to 2 percent 23E—Tricart gravelly loam, 15 to 45 percent slopes ...... 98 slopes ...... 147 64C—Tanna silty clay loam, 2 to 8 percent 30A—Beaverflat loam, 0 to 4 percent slopes ...... 143 slopes ...... 43 65A—Gerdrum clay loam, 0 to 2 percent 36A—Parshall sandy loam, 0 to 4 percent slopes ...... 94 slopes ...... 132 65C—Gerdrum clay loam, 2 to 8 percent 36D—Parshall fine sandy loam, 4 to 15 slopes ...... 94 percent slopes ...... 133 66C—Ethridge silty clay loam, 2 to 8 percent 41C—Yegen loam, 2 to 8 percent slopes...... 172 slopes ...... 91 41D—Yegen loam, 8 to 15 percent slopes...... 172 69C—Twilight fine sandy loam, 2 to 8 percent 42C—Reeder loam, 2 to 8 percent slopes ...... 136 slopes ...... 148 45B—Daglum loam, 0 to 4 percent slopes ...... 80 69D—Twilight fine sandy loam, 8 to 15 48D—Prego sandy loam, 2 to 15 percent percent slopes ...... 149 slopes ...... 134 70C—Busby fine sandy loam, 2 to 8 percent 49A—Beenom-Reeder loams, 1 to 4 percent slopes ...... 59 slopes ...... 44 70D—Busby fine sandy loam, 8 to 15 percent 51C—Abor silty clay loam, 2 to 8 percent slopes ...... 59 slopes ...... 25 71C—Delpoint loam, 2 to 8 percent slopes ...... 84 53C—Orinoco silty clay loam, 2 to 8 percent 72A—Kremlin loam, 0 to 2 percent slopes...... 110 slopes ...... 127 72C—Kremlin loam, 2 to 8 percent slopes ..... 110 54A—Creed loam, 0 to 2 percent slopes ...... 77 74A—Assinniboine sandy clay loam, 0 to 2 54C—Creed loam, 2 to 8 percent slopes ...... 77 percent slopes ...... 37 55D—Blacksheep-Twilight fine sandy loams, 74C—Assinniboine sandy clay loam, 2 to 8 8 to 15 percent slopes...... 50 percent slopes ...... 37 xii

75A—Archin-Absher complex, 0 to 2 percent 94A—Marias silty clay loam, 0 to 2 percent slopes ...... 31 slopes ...... 112 75C—Archin-Absher complex, 2 to 8 percent 94C—Marias silty clay loam, 2 to 8 percent slopes ...... 32 slopes ...... 113 77D—Moyerson silty clay loam, 4 to 15 95A—Teigen silty clay loam, 0 to 4 percent percent slopes ...... 120 slopes ...... 145 78A—Kobase silty clay loam, 0 to 2 percent 95D—Teigen clay loam, gullied, 4 to 15 slopes ...... 108 percent slopes ...... 146 78C—Kobase silty clay loam, 2 to 8 percent 96A—Vaeda silty clay loam, 0 to 2 percent slopes ...... 109 slopes ...... 154 79C—Arsite clay, 0 to 8 percent slopes ...... 35 97A—Vanda silty clay loam, 0 to 2 percent 81C—Marmarth loam, 2 to 8 percent slopes ...... 155 slopes ...... 114 98C—Volborg clay, 2 to 8 percent slopes ...... 160 83A—Chinook sandy loam, 0 to 2 percent 99F—Rentsac-Twilight-Rock outcrop slopes ...... 73 complex, 15 to 45 percent slopes ...... 138 83C—Chinook sandy loam, 2 to 8 percent 112D—Cabba silt loam, 8 to 15 percent slopes ...... 73 slopes ...... 62 83D—Chinook sandy loam, 8 to 15 percent 114C—Carfall-Assinniboine complex, 2 to 8 slopes ...... 74 percent slopes ...... 70 84A—Eapa loam, 0 to 2 percent slopes ...... 87 114D—Carfall-Assinniboine complex, 8 to 15 84C—Eapa loam, 2 to 8 percent slopes ...... 88 percent slopes ...... 71 84D—Eapa loam, 8 to 15 percent slopes ...... 88 116C—Beenom-Parchin complex, 2 to 8 85A—Ethridge loam, 0 to 2 percent slopes ...... 91 percent slopes ...... 45 85C—Ethridge loam, 2 to 8 percent slopes ...... 91 119D—Zeona-Blacksheep-Rock outcrop 86A—Yamacall loam, 0 to 2 percent slopes ... 166 complex, 4 to 15 percent slopes ...... 177 86C—Yamacall loam, 2 to 8 percent slopes ... 166 121C—Parchin-Bullock complex, 2 to 8 86D—Yamacall loam, 8 to 15 percent percent slopes ...... 131 slopes ...... 166 122C—Varney-Gerdrum complex, 2 to 8 87A—Bickerdyke clay, 0 to 2 percent slopes .... 49 percent slopes ...... 158 87C—Bickerdyke clay, 2 to 8 percent slopes .... 49 125F—Dast-Ridge-Rock outcrop complex, 89A—Marvan silty clay, 0 to 2 percent 35 to 60 percent slopes ...... 81 slopes ...... 116 126D—Broadus-Ridge-Reeder complex, 89C—Marvan silty clay, 2 to 8 percent 8 to 25 percent slopes...... 56 slopes ...... 116 126F—Broadus-Ridge-Rock outcrop complex, 90C—Bascovy clay, 2 to 8 percent slopes ...... 39 25 to 65 percent slopes ...... 57 90D—Bascovy clay, 8 to 15 percent slopes ...... 40 130A—Beaverflat sandy loam, 0 to 4 percent 91C—Bonfri loam, 2 to 8 percent slopes ...... 53 slopes ...... 43 91D—Bonfri loam, 8 to 15 percent slopes ...... 53 131C—Shambo-Noonan loams, 4 to 15 92C—Alzada clay loam, 2 to 8 percent percent slopes ...... 141 slopes ...... 30 xiii

136D—Parshall-Cohagen fine sandy loams, 165A—Gerdrum-Absher complex, 0 to 2 4 to 15 percent slopes...... 133 percent slopes ...... 95 141C—Yegen-Rentsac complex, 2 to 8 165C—Gerdrum-Absher complex, 2 to 8 percent slopes ...... 173 percent slopes ...... 95 142D—Reeder-Cabba loams, 4 to 15 percent 167C—Eapa-Yamacall loams, 2 to 8 percent slopes ...... 136 slopes ...... 88 144D—Belltower-Reeder-Vebar complex, 168B—Absher-Gerdrum complex, 0 to 4 4 to 15 percent slopes...... 46 percent slopes ...... 27 144E—Belltower-Dast-Reeder complex, 170D—Busby-Blacksheep-Twilight fine sandy 15 to 35 percent slopes ...... 47 loams, 8 to 25 percent slopes ...... 60 144F—Belltower-Dast complex, 35 to 60 170E—Busby-Blacksheep-Rock outcrop percent slopes ...... 48 complex, 8 to 25 percent slopes ...... 60 152F—Mowbray-Cabba-Vebar complex, 171C—Delpoint-Cabbart complex, 2 to 8 35 to 60 percent slopes ...... 119 percent slopes ...... 85 153D—Orinoco-Yawdim silty clay loams, 171D—Delpoint-Cabbart complex, 8 to 15 4 to 15 percent slopes...... 128 percent slopes ...... 85 154C—Creed-Absher complex, 2 to 8 percent 172C—Kremlin-Cabbart complex, 2 to 8 slopes ...... 78 percent slopes ...... 111 155E—Blacksheep-Rock outcrop complex, 174C—Assinniboine-Ynot complex, 2 to 8 25 to 50 percent slopes ...... 51 percent slopes ...... 38 156A—Havre loam, saline, 0 to 2 percent 175A—Archin loam, 0 to 2 percent slopes...... 33 slopes ...... 104 175C—Archin loam, 2 to 8 percent slopes ...... 33 157A—Harlake silty clay loam, 0 to 2 percent 176D—Kirby-Cabbart complex, 8 to 25 slopes ...... 101 percent slopes ...... 106 158D—Neldore clay, 4 to 15 percent slopes ... 123 177E—Rock outcrop-Moyerson complex, 158E—Neldore clay, 15 to 35 percent 15 to 50 percent slopes ...... 139 slopes ...... 124 178C—Zatoville silty clay loam, 2 to 8 percent 160D—Cambeth-Yamacall complex, 8 to 15 slopes ...... 176 percent slopes ...... 68 179E—Arsite-Rock outcrop complex, 8 to 25 160E—Cabbart-Rock outcrop-Delpoint percent slopes ...... 35 complex, 15 to 50 percent slopes ...... 65 183C—Chinook-Assinniboine complex, 2 to 8 160F—Cabbart-Rock outcrop-Yawdim percent slopes ...... 74 complex, 15 to 70 percent slopes ...... 65 184C—Eapa-Archin loams, 2 to 8 percent 161B—Glendive sandy loam, saline, 0 to 4 slopes ...... 89 percent slopes ...... 98 185A—Ethridge-Daglum complex, 0 to 4 162D—Yawdim silty clay loam, 4 to 15 percent slopes ...... 92 percent slopes ...... 170 186A—Yamacall-Havre loams, 0 to 2 percent 164C—Tanna-Ethridge silty clay loams, slopes ...... 167 2 to 8 percent slopes...... 143 186C—Yamacall-Havre loams, 2 to 8 percent 164D—Tanna-Ethridge silty clay loams, slopes ...... 167 8 to 15 percent slopes...... 144 xiv

191C—Bonfri-Cambeth complex, 2 to 8 260E—Cambeth-Cabbart-Yawdim complex, percent slopes ...... 53 15 to 25 percent slopes ...... 69 193C—Yamacall-Cambeth complex, 2 to 8 262E—Yawdim-Blacksheep-Rock outcrop percent slopes ...... 168 complex, 15 to 45 percent slopes ...... 171 196C—Vaeda-Creed complex, 0 to 4 percent 269C—Twilight-Bonfri complex, 2 to 8 percent slopes ...... 154 slopes ...... 149 197A—Vanda-Marvan complex, 0 to 2 269D—Twilight-Bonfri complex, 8 to 15 percent slopes ...... 155 percent slopes ...... 150 197C—Vanda-Marvan complex, 2 to 8 270E—Busby, gullied-Delpoint-Yawdim percent slopes ...... 156 complex, 8 to 25 percent slopes ...... 61 198D—Volborg silty clay, saline, 4 to 15 271D—Delpoint-Yamacall loams, 8 to 15 percent slopes ...... 161 percent slopes ...... 86 212E—Cabba-Rock outcrop complex, 275D—Archin, gullied-Delpoint complex, 15 to 45 percent slopes ...... 63 4 to 15 percent slopes...... 33 214C—Carfall fine sandy loam, 2 to 8 percent 276F—Kirby-Blacksheep-Rock outcrop slopes ...... 71 complex, 25 to 60 percent slopes ...... 107 214D—Carfall fine sandy loam, 8 to 15 277D—Moyerson-Orinoco silty clay loams, percent slopes ...... 72 4 to 15 percent slopes...... 121 225E—Dast-Vebar complex, 15 to 35 percent 283C—Chinook-Archin complex, 2 to 8 slopes ...... 82 percent slopes ...... 75 225F—Dast-Vebar complex, 35 to 60 percent 286C—Yamacall-Delpoint loams, 2 to 8 slopes ...... 82 percent slopes ...... 168 231D—Shambo-Mowbray-Parchin complex, 291D—Bonfri-Cabbart loams, 8 to 15 percent 4 to 25 percent slopes...... 142 slopes ...... 54 242D—Reeder-Dast complex, 4 to 15 percent 298E—Volborg-Julin-Rock outcrop complex, slopes ...... 136 8 to 25 percent slopes...... 161 251D—Abor-Yawdim silty clay loams, 4 to 15 312D—Cabba-Dast complex, 8 to 15 percent percent slopes ...... 25 slopes ...... 63 253D—Orinoco-Weingart complex, 4 to 15 325E—Dast-Cabba-Mowbray complex, 15 to percent slopes ...... 128 35 percent slopes...... 83 254C—Creed-Gerdrum complex, 2 to 8 358D—Neldore-Bascovy clays, 4 to 15 percent slopes ...... 78 percent slopes ...... 125 256A—Havre-Harlake complex, 0 to 2 360D—Cabbart-Bascovy complex, 4 to 15 percent slopes ...... 104 percent slopes ...... 66 258D—Neldore-Volborg clays, 4 to 15 369C—Twilight-Delpoint complex, 2 to 8 percent slopes ...... 124 percent slopes ...... 150 260C—Cambeth-Cabbart silt loams, 2 to 8 369D—Twilight-Cabbart complex, 8 to 15 percent slopes ...... 68 percent slopes ...... 151 260D—Cabbart-Cambeth silt loams, 8 to 15 375C—Archin-Ynot complex, 2 to 8 percent percent slopes ...... 66 slopes ...... 34 xv

386E—Yamacall-Cabbart loams, 15 to 35 613B—Marvan-Vanda clays, warm, 0 to 3 percent slopes ...... 169 percent slopes ...... 116 391C—Bonfri-Parchin complex, 2 to 8 percent 614C—Marvan clay, warm, 0 to 6 percent slopes ...... 55 slopes ...... 117 398E—Volborg-Volborg, saline-Rock outcrop 620C—Weingart silty clay loam, warm, complex, 8 to 45 percent slopes ...... 162 0 to 6 percent slopes...... 164 477E—Moyerson silty clay loam, 15 to 35 621C—Alona silt loam, warm, 2 to 8 percent percent slopes ...... 121 slopes ...... 29 490C—Bascovy-Ethridge complex, 2 to 8 623D—Bascovy clay, warm, 0 to 9 percent percent slopes ...... 40 slopes ...... 41 586D—Yamacall-Delpoint-Cabbart loams, 625E—Neldore clay, warm, 3 to 25 percent 8 to 15 percent slopes...... 169 slopes ...... 125 590C—Bascovy-Marvan complex, 2 to 8 626C—Ethridge silty clay loam, warm, 2 to 8 percent slopes ...... 40 percent slopes ...... 92 602C—Creed-Gerdrum complex, warm, 2 to 6 629C—Marmarth loam, warm, 2 to 8 percent percent slopes ...... 79 slopes ...... 114 603C—Eapa loam, warm, 1 to 6 percent 631D—Orinoco-Yawdim silty clay loams, slopes ...... 89 warm, 4 to 15 percent slopes ...... 129 605E—Moyerson, warm-Rock outcrop 633D—Bascovy-Neldore clays, warm, 6 to 21 complex, 9 to 45 percent slopes ...... 121 percent slopes ...... 41 606B—Harlake silty clay loam, warm, saline, 634E—Volborg-Julin complex, warm, 6 to 60 0 to 3 percent slopes...... 102 percent slopes ...... 162 608B—Harlake clay, warm, 0 to 3 percent 635C—Marvan-Bascovy clays, warm, 0 to 6 slopes ...... 102 percent slopes ...... 117 611B—Gerdrum-Absher complex, warm, DA—Denied access ...... 86 0 to 3 percent slopes...... 96 M-W—Miscellaneous water...... 118 611D—Gerdrum-Absher complex, warm, W—Water ...... 163 3 to 9 percent slopes...... 96 xvi

Summary of Tables

Part I

Temperature and precipitation ...... 8

Freeze dates in spring and fall ...... 10

Growing season ...... 12

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

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 Carter County, Montana

Fieldwork by Richard G. Bandy, Gary F. Berger, James F. Dorr, John A. Lindahl, Dan L. McLean, William R. Johnson, and Kenneth T. Scalzone, Natural Resources Conservation Service

United States Department of Agriculture, Natural Resources Conservation Service, in cooperation with the United States Department of Agriculture, Forest Service; United States Department of the Interior, Bureau of Land Management; and the Montana Agricultural Experiment Station

CARTER COUNTY is located in southeastern Montana (fig. 1). It has a land area of 2,139,300 acres, or 3,342 square miles. Nearly a third of the county consists of Federal land. The major occupations in Carter County are ranching and dryland farming. The county is the largest producer of sheep and lambs in Montana. About 10 percent of the county is used for dryland farming, with the majority used mainly for range. Elevations range from 2,760 to 4,450 feet. The annual precipitation ranges from 12 to 17 inches, and the frost-free period ranges from 110 to 130 days. Descriptions, names, and delineations of soils in this soil survey do not fully agree with those on soil Figure 1.—Location of Carter County, Montana maps for adjacent survey areas. Differences are the result of better knowledge of soils, modifications in series concepts, intensity of mapping, and the extent Carter County was established in 1917 and was of soils within the survey. named in honor of Thomas Henry Carter, Montana’s first representative to Congress. Ekalaka, the county General Nature of the Survey Area seat, is located in the north-central part of the county and is the largest town. The other town of significant This section describes some of the environmental population is Alzada, located in the southern part of and cultural features that affect the use and the county. management of soils in the survey area. These Carter County is located in an area known as the features are history, industry and recreation, rolling prairie. In 1882, the first herd of cattle was physiography and drainage, geology, mineral trailed from Texas to Box Elder Creek. In 1897, the resources, ground-water resources, and climate. first school in the county was built near Ekalaka. In late 1908, the Chicago, Milwaukee, St. Paul, and History Pacific Railroad was completed through the town of Baker, located 36 miles north of Ekalaka in Fallon The first known inhabitants of Carter County were County. Baker became the main freight station and Native American hunters who followed bison herds point of departure for hundreds of homesteaders into the area. seeking plots of land to make their fortunes. 2 Soil Survey

Schoolhouses became a part of every community, southeast corner of the county and extends into the and many post offices were established, generally in Black Hills of Wyoming and South Dakota. ranch or farm homes. In the 1930s, hard times hit and The county consists predominantly of gently rolling many homesteads were abandoned. plains with shallow creek valleys and broad flat divides. The landscape is semiarid with infrequent Industry and Recreation badland areas. Remnants of younger, relatively resistant sandstone formations form the prominent Raising livestock, growing crops, and mining pinnacles and ridges of the Ekalaka Hills, Long Pine bentonite are the principal industries in Carter Hills, and Chalk Buttes. Landscapes typical in the County. Livestock operations, primarily cow-calf and northeastern part of the county are flat-topped buttes sheep, account for nearly 82 percent of the farm and summits capped by sandstone or resistant baked income. The main dryland-farming crop is winter shale and clinker (scoria) beds. Topography in the wheat. Other crops, such as spring wheat, barley, and central portion of the county is more subdued, grass hay, are also grown. Some alfalfa and grass containing large flat areas with little relief. hay are grown on waterspreading systems, which are Relatively resistant reddish baked shale beds can located along Beaver and Box Elder Creeks and the be seen capping summits in the northeastern part of Little Missouri River. the county; these beds were formed by burning Livestock auction yards in Baker and Miles City, underground coal seams. Burning coal baked the Montana, and Belle Fourche, South Dakota, provide surrounding sediments and made them more ranchers with good livestock marketing facilities. resistant to erosion. Some of the calves are sold directly from the ranch to In this semiarid climate, landscape is directly feeder buyers. Nearly all of the small grain produced controlled by the characteristics of underlying is marketed through elevators in Baker, Miles City, bedrock. Elevations range from a low of 2,760 feet and Belle Fourche. above sea level to a high of 4,450 feet. The lowest The Alzada area is an important bentonite mining point is located where Spring Creek exits the county area. The bentonite produced here is shipped via at the western county line. West Butte, located truck to the Colony, Wyoming, area for refining. 6 miles north of the southwestern corner, is the Carter County offers numerous opportunities for highest point in the county. outdoor recreation. Mule deer, white-tailed deer, and The major northeast flowing drainages are Box antelope populations, along with upland game birds, Elder Creek and the Little Missouri River. Box Elder such as Merriam’s turkey, sage grouse, sharp-tailed Creek drains the central portion of the county. It is grouse, and Hungarian partridge, create excellent perennial north of the town of Ridgway. The Little hunting opportunities. Many small ponds provide Missouri River is located to the southeast of Box good fishing. Elder Creek and is perennial throughout Carter Medicine Rocks State Park and the abundance of County. The northwestern corner of the county is forested lands in the county provide tremendous drained by O’Fallon Creek, draining to the northwest. opportunity for camping, picnicking, hiking, and The extreme southeastern corner drains southeast, photography. The Carter County Historical Museum is toward the Belle Fourche River, which is located in renown for its paleontological collections and early Wyoming and South Dakota. human artifacts. Major streams, with numerous ephemeral tributaries arranged in a relatively linear dendritic Physiography and Drainage pattern, follow meandering courses in wide, nearly level valley bottoms. The pattern is approximately Mary Marshall Garsjo, State Geologist, Natural Resources parallel to the strike of the formations. Conservation Service, prepared the Physiography and Drainage, Geology, Mineral Resources, and Ground-water Resources sections. Geology

The entire county is located within the Missouri The oldest rocks exposed in Carter County belong Plateau physiographic province. The county is divided to sedimentary formations deposited during the into two physiographic subprovinces by a northwest- Cretaceous Period. At that time, a transcontinental trending line that runs through the center. This line sea covered the area between the Gulf of Mexico and separates the Montana Plains Province to the north the Arctic Ocean. Thick sequences of sediments were from the Central Rocky Mountain Foreland Province deposited on coastal plains and shallow sea floors to the south. The Black Hills Uplift begins in the during alternating periods of emergence and Carter County, Montana—Part I 3

submergence. These repeated marine invasions Cretaceous System (135- to 65-million years created a thick sequence of marine shales deposited before present): The oldest rocks exposed in Carter on the sea floor. Brackish shales, freshwater shales, County belong to the Colorado Group. This group is and sandstones were deposited on the coastal plains. approximately 2,000-feet thick and is composed of These sandstone and shale beds grade both formations that are primarily marine shale. vertically and horizontally into each other. Formations of the Colorado Group are exposed in an Marine migrations continued without interruption arcuate pattern in the south-central portion of the until the Late Cretaceous Period, when uplift of the county. In order of decreasing age, these formations Rocky Mountains began in western Montana. Marine include the Thermopolis Formation, with its upper deposition ended in Carter County at the end of Newcastle Sandstone Member; Mowry Shale; Belle Pierre Shale time. The overlying Hell Creek Fourche Shale; Greenhorn Formation; Carlile Shale; Formation was the last unit to be deposited in the and the Niobrara Formation. Late Cretaceous Period. The extinction of dinosaurs, Formations in the Colorado Group consist approximately 65-million years ago, marked the end primarily of shale with smaller amounts of of the Cretaceous Period. At this time, fossils interbedded sandstone, siltstone, and marl (a changed dramatically, but the character of the calcareous shale). Most of these formations contain sediments remained the same. limestone and iron concretions. Bentonite occurs in Volcanism occurring to the west, during the beds from a few inches to several feet thick. The Cretaceous Period, spread thick layers of volcanic Gerdrum, Marvan, and Neldore soil series typically ash over the area. Bentonite, which is derived from are derived from this group. devitrified volcanic ash, occurs in many of the Directly overlying the Colorado Group is the Pierre Cretaceous sediments, particularly the marine Shale. It occupies most of central Carter County, shales. Bentonite is found in layers from a few inches between Cottonwood and Big Ramme Creeks. The thick to mineable beds with thicknesses up to 10 feet. Pierre Shale is 1,500- to 2,000-feet thick and consists Deposition of massive amounts of sediment from primarily of dark gray marine shale. Interbedded in the Rocky Mountain Uplift continued during the the shale are bentonite beds, iron concretions, Tertiary Period. Sluggish rivers meandering across limestone concretions, veins and crystals of gypsum, the coastal plains deposited these sediments. The and local sandstone lenses. Many saline pan spots coastal plains were swampy and covered with lush are associated with this formation. On the weathered vegetation. These marshes were eventually buried by exposures, gypsum crystals glitter in the sun like accumulating sediments and converted to coal. broken glass. Small lenses of clean, rounded quartz Approximately 50-million years ago, uplift and pebbles, weathered from the Pierre Shale, can be granitic intrusions occurred in the Black Hills area to found capping small rises. The Gerdrum, Marvan, the southeast. This igneous activity was accompanied and Neldore soil series are also typically derived from by regional folding and faulting, including the this formation. formation of the Cedar Creek anticline and the The overlying Fox Hills Sandstone consists of adjacent Ekalaka syncline, between the Powder River cross-bedded sandstone, siltstone, and shale from Basin and the Williston Basin, and the Black Hills marine and brackish water deposits. It is 25- to Uplift to the east of the Power River Basin. The Black 100-feet thick and crops out in a relatively narrow Hills Uplift domed the overlying sedimentary band surrounding the Pierre Shale. The upper formations upward as it rose. These sediments member of the Fox Hills Sandstone is the Colgate currently surround it in a concentric pattern of Member. It is a light-colored, permeable sandstone decreasing age. In general, rocks of southern Carter that is distinct from the darker underlying material. County influenced by the Black Hills Uplift occur in an The Colgate Member is locally thin or absent. The arcuate pattern typical of an anticlinal fold, with age formation becomes more shaly downward and grades decreasing to the north. into the underlying Pierre Shale. The Blacksheep and Summarized below and listed in order of Twilight soil series typically are derived from this decreasing age is the sequence of exposed rocks for formation. the county. Classification of rock units based on their The Hell Creek Formation overlies the Fox Hills lithology is group, formation, and member, from Sandstone, ranging from 20- to 30-feet thick in this largest to smallest. For example, formations are area. This formation consists of nonmarine and subdivided into members. “Systems” refers to the brackish water deposits of sandstone and shale and rocks deposited during a particular geologic period. contains the last of the dinosaur fossils. Together with 4 Soil Survey

the underlying Colgate Member, this formation The Chadron Formation consists of interbedded becomes sandier downward and forms a relatively conglomerate and limestone with sandstone and pale thick and continuous aquifer. This aquifer supplies green bentonitic shales. The overlying Brule much of the domestic and stock water in the region. Formation consists of massive orange and pink The Archin, Eapa, and Ynot soil series typically are tuffaceous siltstone with interbeds of shale and derived from this formation. sandstone. The White River Group has relatively high Tertiary System (65- to 2.5-million years before permeability but is generally not considered an present): The Fort Union Formation overlies the Hell aquifer because of its limited recharge area. Creek Formation and is exposed in the northeastern The Arikaree Formation overlies the White River part of the county. This formation covers a large Group in the Ekalaka Hills and has a wider portion of eastern Montana but does not occur in distribution in South Dakota and Wyoming. This significant quantities in Carter County. In this area, formation is up to 250-feet thick and forms resistant the Fort Union Formation has a maximum thickness bluffs in the southern margin of the Ekalaka Hills, of 1,800 feet and has been subdivided into the lower Long Pine Hills, and Chalk Buttes. The Arikaree Ludlow Member and the upper Tongue River Member. Formation consists of light-colored tuffaceous Like the Hell Creek Formation, the Fort Union sandstone and shales with interbedded volcanic ash Formation consists of sandstone, shale, and coal and is locally capped by hard green quartzite. The beds. Brick red summits and shoulders of hills formed Belltower, Dast, and Vebar soil series typically are from baked shale give the outcrops a distinctive derived from this formation. appearance. Thin sandy soils mantle the sandstone Slump areas are located at the base of the summits. Deeper soils occur on the intermediate Ekalaka Hills, Long Pine Hills, and Chalk Buttes. valleys that are eroded into shales. There are 6- to These areas are composed of both Tertiary- and 12-feet thick gravel terraces associated with this Cretaceous-aged sedimentary rocks. Most of this formation. The gravels of these terraces are both movement occurred in the Miocene Epoch (mid- cleaner and younger than the gravels associated with Tertiary Period). The Miocene Epoch was more humid the Pierre Shale. than the contemporary climate. This additional In most of the Tongue River Member, shale occurs moisture compounded generally unstable conditions more frequently than sandstone; however, shale in the Brule Formation. The resulting soils have been weathers more rapidly into soil-covered slopes and is mapped in the Haploboroll and Ustochrept families. not as conspicuous as the sandstone. The Tongue At the north end of the county, Medicine Rocks River Member is the chief coal-bearing formation in State Park consists of unusual and spectacular eastern Montana and contains many thick coal beds. geology. The park contains knobs and ridges that The Cabbart, Cambeth, and Eapa soil series typically formed in the soft erodible sandstone of the Tongue are derived from this member. The Kirby soil series River Member. These features are considered developed on the baked shale. remnants of an old dune field that were shaped by The Ludlow Member consists of interbedded wind erosion. Like contemporary dune fields, the sandstone, siltstone, and shale and weathers to sand grains are small and uniform and have a badlands-like topography. In other areas of Montana, crossbedded structure. the Ludlow Member is subdivided into the upper Lebo Shale and lower Tullock Members. Coal in the Ludlow Mineral Resources Member occurs as thin lenticular beds. The Archin, Bonfri, and Chinook soil series typically are derived Carter County is located within eastern Montana’s from this member. oil and gas producing region. Oil and gas are Directly overlying the Tongue River Member, the produced from different stratigraphic horizons. Oil and White River Group is exposed only in small areas of gas accumulation is a factor of both geologic higher hills. This group is subdivided into two structure and porosity variations within individual formations, the older Chadron Formation and the formations. overlying Brule Formation. They crop out in the Two oil and gas fields have been developed in the summits and pinnacles of Long Pine Hills as small county. Hammond Field is located northwest of exposures overlying the Tongue River. The White Alzada, and Repeat Field is located south of the River Group is more widely distributed in South Humbolt Hills near the South Dakota border. Dakota and does not occur in other areas of In the Repeat Field, oil and associated gas are Montana. produced from the Red River Formation. This Carter County, Montana—Part I 5

formation is of mid-Ordovician-age and consists of They contain only small amounts of saline water, limestone and dolomite. The Red River Formation is which is often too mineralized for any use. Drill one of the most widespread formations in the depths to underlying artesian aquifers can be quite Williston Basin and is one of its main hydrocarbon deep. reservoirs. The Repeat Field is associated with the Sandstone beds occur In the Pierre Formation and Fallon County fields along the crest of the Cedar the underlying Newcastle, Muddy, and Lakota Creek anticline to the east. Sandstones. Deep wells have been successfully Hammond Field produced natural gas from the completed in these sandstone beds. Because of Muddy Sandstone Member of the lower Cretaceous structural configuration, wells occur under artesian Colorado Group. In the past several years, there has conditions. Some wells may flow depending on their not been any production from this field. location. Carter County contains significant exposures of Ground water in northern Carter County is formations that are known to contain mineable beds obtained primarily from the Fox Hills-Lower Hell of bentonite. Bentonite beds occur in the Arikaree Creek aquifer wherever the overlying Fort Union Formation, the Monument Hill Bentonitic Member of Formation is not too thick. Total dissolved solids the Pierre Formation, and the Belle Fourche and concentration from this aquifer are generally low, Mowry Shales. ranging from well under 500 to 2,000 mg/l. The best Potentially economic deposits of lignite are present quality water is found near recharge areas. Average in Carter County. Lignite is soft and crumbly and yields are 10 gallons-per-minute (gpm), though yields contains significant moisture. It has the lowest heat of as high as 40 gpm are possible. content of coal types. These deposits have In the Fort Union Formation, the Tongue River undergone little development. They occur in relatively Member typically yields 8 to 15 gpm, and the more thin, less than 10-feet thick, beds in the Tongue River shaly Ludlow Member typically yields 3 to 8 gpm. Member. A few thin beds also occur in the underlying Water is produced from frequently occurring Ludlow Member and Hell Creek Formation. sandstone and baked shale beds. These beds occur The Ekalaka Lignite Field produced 2,250 tons of as discontinuous lenses with limited areal extent. lignite between 1926 and 1934. There has been no Their exact locations are impossible to predict at a further reported development of this field. particular site. After years of use, shallow wells often Current economic geology maps do not designate fail when the limited sandstone lens is completely “strippable coal reserves” in Carter County. Minor drained. amounts of uranium have been found in lignite beds Water in the Fort Union Formation contains total that crop out along the Ekalaka Hills and Long Pine dissolved solids concentrations (TDS) ranging from Hills. Uranium was leached by ground water from 400 to 2,000 mg/l. In general, the best quality water is windblown tuffs or weathered igneous rocks and obtained from baked shale beds. The Environmental deposited in organic-rich lignite. Most uranium in the Protection Agency has recommended a maximum county has been found in the Fort Union Formation TDS concentration of 500 mg/l for human and the overlying Arikaree Formation. Uranium also consumption. Water with greater than 7,000 mg/l TDS occurs at depth in lower Cretaceous Formations that is generally considered unfit for any use. do not crop out in the area. Unconsolidated deposits of alluvium occur in the Aggregate, such as sand and gravel, used to make valleys of larger streams. These deposits, consisting concrete occur in mineable quantities within the of interbedded clay, silt, sand, and gravel, have county. thicknesses up to 50 feet and are commonly used for ground-water development. They produce average Ground-water Resources yields of 15 gpm. TDS concentrations range from 450 to 6,000 mg/l. Usable ground-water aquifers occur at the surface The Montana Bureau of Mines and Geology’s only in the northern and northeastern portions of Open File Report HY77-1, Compilation of Carter County. The remaining shale formations, Hydrogeological Data for Southeastern Montana, exposed to the south, are generally impermeable. reported a total of 867 wells in Carter County in 1977. 6 Soil Survey

Their average depth was 172 feet, with average static vegetation of the survey area. Each kind of soil and water levels of 72 feet. In 70 percent of the wells, miscellaneous area is associated with a particular static water level was less than 160 feet. kind of landform or with a segment of the landform. Well use current to April 1991 is summarized By observing the soils and miscellaneous areas in below. Often wells have multiple uses and are listed the survey area and relating their position to specific under both domestic and stockwater supplies, segments of the landform, soil scientists develop a causing the total to appear less than the sum of the concept, or model, of how the soils were formed. uses. This information was provided by the Montana During mapping, this model enables soil scientists to Groundwater Information Center, Butte, Montana. predict with a considerable degree of accuracy the Stockwater ...... 918 kind of soil or miscellaneous area at a specific Household and Domestic ...... 239 location on the landscape. Unknown ...... 33 Individual soils on the landscape commonly merge Other ...... 3 into one another as their characteristics gradually Industrial ...... 2 change. To construct an accurate map, however, soil Unused ...... 1 scientists must determine the boundaries between the soils. They can observe only a limited number of TOTAL WELLS ...... 1,089 soil profiles. Nevertheless, these observations, supplemented by an understanding of the soil- Climate vegetation-landscape relationship, are sufficient to verify predictions of the kinds of soil in an area and to Following this section are tables giving data on determine the boundaries. temperature and precipitation, probable dates of the Soil scientists recorded the characteristics of the first freeze in fall and the last freeze in spring, and soil profiles that they studied. They noted color, data on length of the growing season. texture, size, and shape of soil aggregates; kind and Growing-degree days are the equivalent to “heat amount of rock fragments; distribution of plant roots; units.” During the month, growing-degree days reaction; and other features that enable them to accumulate by the amount that the average identify soils. After describing the soils in the survey temperature each day exceeds a base temperature area and determining their properties, soil scientists (40 degrees F). The normal monthly accumulation is assigned the soils to taxonomic classes (units). used to schedule single or successive plantings of a Taxonomic classes are concepts. Each taxonomic crop between the last freeze in spring and the first class has a set of soil characteristics with precisely freeze in fall. defined limits. The classes are used as a basis for comparison to classify soils systematically. Soil How This Survey Was Made taxonomy, the system of taxonomic classification used in the United States, is based mainly on the This survey was made to provide information kind and character of soil properties and the about the soils and miscellaneous areas in the arrangement of horizons within the profile. After the survey area. This information includes a description soil scientists classified and named the soils in the of the soils and miscellaneous areas and their survey area, they compared the individual soils with location and a discussion of their suitability, similar soils in the same taxonomic class in other limitations, and management for specified uses. Soil areas so that they could confirm data and assemble scientists observed the steepness, length, and shape additional data based on experience and research. of the slopes; the general pattern of drainage; the While a soil survey is in progress, samples of kinds of crops and native plants; and the kinds of some of the soils in the area generally are collected bedrock. They dug many holes to study the soil for laboratory analyses and for engineering tests. Soil profile, which is the sequence of natural layers, or scientists interpret data from these analyses and horizons, in a soil. The profile extends from the tests as well as field-observed characteristics and soil surface down into the unconsolidated material in properties to determine the expected behavior of the which the soil formed. The unconsolidated material is soils under different uses. Interpretations for all of the devoid of roots and other living organisms and has soils are field tested through observation of the soils not been changed by other biological activity. in different uses and under different levels of The soils and miscellaneous areas in the survey management. Some interpretations are modified to fit area are in an orderly pattern that is related to the local conditions, and some new interpretations are geology, landforms, relief, climate, and natural developed to meet local needs. Data are assembled Carter County, Montana—Part I 7

from other sources, such as research information, After soil scientists located and identified the production records, and field experience of significant natural bodies of soil in the survey area, specialists. For example, data for crop yields under they drew the boundaries of these bodies on aerial high levels of management are modeled and photographs and identified each as a specific map validated with farm records and field or plot unit. Aerial photographs show trees, buildings, fields, information on the same kinds of soil. roads, and rivers, all of which help in locating Predictions about soil behavior are based not only boundaries accurately. on soil properties but also on such variables as Descriptions, names, and delineations of the soils climate and biological activity. Soil conditions are in this survey area may not fully agree with those of predictable over long periods, but they are not the soils in adjacent survey areas. Differences result predictable from year to year. For example, soil from a better knowledge of soils, modifications in scientists can predict with a fairly high degree of series concepts, or variations in the intensity of accuracy that a given soil will have a high water table mapping or in the extent of the soils in the survey within certain depths in most years, but they cannot areas. predict that a high water table will always be at a specific level in the soil on a specific date. 8 Soil Survey

Temperature and Precipitation

(Recorded in the period 1964-1994 at Albion, Ekalaka, and Ridgway)

______| | | Temperature (Degrees F) | Precipitation (Inches) |______| | | | | | | | | | | | | | 2 years |Average| | 2 years |Average| Month | | | | in 10 |Number | | in 10 |Number | |Average|Average| | Will Have— | of | | Will Have— |of Days|Average | Daily | Daily |Average| | |Growing|Average| | | With | Total |Maximum|Minimum| | Maximum | Minimum |Degree | |Less | More |0.10 or|Snowfall | | | |Temperature|Temperature| Days* | |Than | Than | More | | | | | More Than | Less Than | | | | | | ______| | | | | | | | | | | | | | | | | | | | | | ALBION: | | | | | | | | | | | | | | | | | | | | | | January----| 28.5 | 1.0 | 14.8 | 54 | -36 | 1 | 0.28 |0.11 | 0.46 | 1 | 3.0 February---| 34.4 | 6.3 | 20.3 | 62 | -31 | 5 | 0.28 |0.07 | 0.47 | 0 | 3.2 March------| 44.9 | 17.6 | 31.2 | 72 | -14 | 23 | 0.51 |0.26 | 0.82 | 1 | 3.7 April------| 57.0 | 28.2 | 42.6 | 84 | 6 | 122 | 1.56 |0.51 | 2.41 | 3 | 6.9 May------| 68.4 | 38.9 | 53.7 | 91 | 19 | 371 | 2.12 |1.13 | 2.99 | 5 | 0.6 June------| 76.7 | 47.9 | 62.3 | 99 | 32 | 608 | 3.15 |1.95 | 4.23 | 7 | 0.0 July------| 86.1 | 53.0 | 69.5 | 104 | 37 | 827 | 1.82 |0.57 | 2.83 | 4 | 0.0 August-----| 85.7 | 50.2 | 68.0 | 104 | 32 | 737 | 1.28 |0.40 | 2.00 | 2 | 0.0 September--| 74.3 | 39.1 | 56.7 | 100 | 20 | 435 | 0.99 |0.35 | 1.58 | 3 | 0.6 October----| 60.8 | 28.1 | 44.5 | 87 | 2 | 171 | 1.12 |0.40 | 1.80 | 2 | 0.7 November---| 41.8 | 15.3 | 28.5 | 70 | -19 | 15 | 0.42 |0.16 | 0.63 | 1 | 3.4 December---| 32.5 | 5.1 | 18.8 | 61 | -31 | 2 | 0.41 |0.16 | 0.65 | 1 | 4.7 | | | | | | | | | | | Yearly: | | | | | | | | | | | Average---| 57.6 | 27.6 | 42.6 | ——— | ——— | ——— | ——— | ——— | ——— | ——— | ——— Extreme---| 108.0 | -48.0 | ——— | 106 | -38 | ——— | ——— | ——— | ——— | ——— | ——— Total-----| ——— | ——— | ——— | ——— | ——— | 3,316 | 13.93 |8.88 |16.10 | 30 | 26.8 | | | | | | | | | | | | | | | | | | | | | | EKALAKA: | | | | | | | | | | | | | | | | | | | | | | January----| 29.5 | 6.9 | 18.2 | 56 | -30 | 3 | 0.53 |0.22 | 0.78 | 1 | 0.0 February---| 34.9 | 12.4 | 23.7 | 59 | -25 | 7 | 0.44 |0.17 | 0.69 | 1 | 0.5 March------| 44.2 | 20.5 | 32.4 | 71 | -14 | 44 | 0.71 |0.29 | 1.07 | 2 | 1.1 April------| 57.1 | 30.8 | 43.9 | 82 | 6 | 181 | 1.77 |0.76 | 2.64 | 4 | 0.1 May------| 68.3 | 40.9 | 54.6 | 90 | 20 | 448 | 2.57 |1.28 | 3.69 | 5 | 0.0 June------| 77.4 | 49.6 | 63.5 | 96 | 33 | 698 | 3.64 |2.10 | 5.01 | 6 | 0.0 July------| 85.6 | 55.4 | 70.5 | 101 | 39 | 936 | 1.77 |0.68 | 2.69 | 3 | 0.0 August-----| 84.0 | 53.3 | 68.6 | 99 | 34 | 875 | 1.24 |0.41 | 2.00 | 3 | 0.0 September--| 72.0 | 42.7 | 57.3 | 96 | 22 | 512 | 1.57 |0.43 | 2.48 | 3 | 0.0 October----| 59.3 | 31.9 | 45.6 | 83 | 6 | 229 | 1.32 |0.52 | 2.06 | 2 | 0.3 November---| 42.1 | 19.7 | 30.9 | 70 | -12 | 34 | 0.68 |0.24 | 1.04 | 2 | 2.7 December---| 32.1 | 10.2 | 21.2 | 59 | -29 | 6 | 0.63 |0.22 | 0.97 | 2 | 2.6 | | | | | | | | | | | Yearly: | | | | | | | | | | | Average---| 57.2 | 31.2 | 44.2 | ——— | ——— | ——— | ——— | ——— | ——— | ——— | ——— Extreme---| 105.0 | -43.0 | ——— | 102 | -34 | ——— | ——— | ——— | ——— | ——— | ——— Total-----| ——— | ——— | ——— | ——— | ——— | 3,973 | 16.87 |12.78|20.16 | 34 | 7.4 | | | | | | | | | | |

See footnote at end of table. Carter County, Montana—Part I 9

Temperature and Precipitation--Continued ______| | | Temperature (Degrees F) | Precipitation (Inches) |______| | | | | | | | | | | | | | 2 years |Average| | 2 years |Average| Month | | | | in 10 |Number | | in 10 |Number | |Average|Average| | Will Have— | of | | Will Have— |of Days|Average | Daily | Daily |Average| | |Growing|Average| | | With | Total |Maximum|Minimum| | Maximum | Minimum |Degree | |Less | More |0.10 or|Snowfall | | | |Temperature|Temperature| Days* | |Than | Than | More | | | | | More Than | Less Than | | | | | | ______| | | | | | | | | | | | | | | | | | | | | | RIDGWAY: | | | | | | | | | | | | | | | | | | | | | | January----| 28.7 | 3.0 | 15.8 | 54 | -32 | 1 | 0.32 | 0.17| 0.62 | 1 | 5.1 February---| 34.2 | 8.8 | 21.5 | 59 | -29 | 4 | 0.28 | 0.09| 0.50 | 1 | 4.3 March------| 43.7 | 19.1 | 31.4 | 72 | -16 | 30 | 0.68 | 0.18| 1.17 | 1 | 6.9 April------| 57.0 | 30.5 | 43.8 | 83 | 8 | 169 | 1.51 | 0.60| 2.28 | 4 | 4.3 May------| 67.7 | 40.6 | 54.2 | 90 | 21 | 430 | 2.30 | 0.95| 3.45 | 5 | 0.4 June------| 76.6 | 49.6 | 63.1 | 97 | 32 | 663 | 2.69 | 1.74| 3.54 | 6 | 0.1 July------| 85.0 | 55.5 | 70.3 | 102 | 39 | 881 | 1.69 | 0.66| 2.56 | 4 | 0.0 August-----| 84.2 | 52.8 | 68.5 | 100 | 34 | 832 | 1.04 | 0.53| 1.61 | 2 | 0.0 September--| 72.6 | 41.3 | 56.9 | 97 | 20 | 490 | 1.21 | 0.39| 2.03 | 3 | 0.8 October----| 60.2 | 29.8 | 45.0 | 85 | 3 | 201 | 1.01 | 0.34| 1.69 | 2 | 1.7 November---| 42.5 | 16.8 | 29.7 | 72 | -17 | 26 | 0.53 | 0.19| 0.95 | 1 | 4.7 December---| 32.0 | 6.3 | 19.1 | 59 | -34 | 2 | 0.48 | 0.19| 0.87 | 1 | 5.4 | | | | | | | | | | | Yearly: | | | | | | | | | | | Average---| 57.0 | 29.5 | 43.3 | ——— | ——— | ——— | ——— | ——— | ——— | ——— | ——— Extreme---| 108.0 | -51.0 | ——— | 103 | -39 | ——— | ——— | ——— | ——— | ——— | ——— Total-----| ——— | ——— | ——— | ——— | ——— | 3,728 | 13.75 |10.39|16.35 | 31 | 33.7 ______| | | | | | | | | | |

* 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 (Threshold: 40.0 degrees F). 10 Soil Survey

Freeze Dates in Spring and Fall

(Recorded in the period 1964-1994 at Albion, Ekalaka, and Ridgway)

______| | Temperature |______Probability | | | | 24 Degrees F | 28 Degrees F | 32 Degrees F | or Lower | or Lower | or Lower ______| | | | | | ALBION: | | | | | | Last freezing temperature | | | in spring: January-July | | | | | | 1 year in 10 later than------| May 16 | May 31 | June 7 | | | 2 years in 10 later than------| May 12 | May 25 | June 2 | | | 5 years in 10 later than------| May 2 | May 13 | May 24 | | | First freezing temperature | | | in fall: August-December | | | | | | 1 year in 10 earlier than-----| September 13 | September 4 | August 27 | | | 2 years in 10 earlier than----| September 18 | September 8 | August 31 | | | 5 years in 10 earlier than----| September 28 | September 17 | September 10 | | | | | | EKALAKA: | | | | | | Last freezing temperature | | | in spring: January-July | | | | | | 1 year in 10 later than------| May 10 | May 20 | June 6 | | | 2 years in 10 later than------| May 5 | May 15 | June 1 | | | 5 years in 10 later than------| April 25 | May 5 | May 21 | | | First freezing temperature | | | in fall: August-December | | | | | | 1 year in 10 earlier than-----| September 16 | September 9 | September 1 | | | 2 years in 10 earlier than----| September 22 | September 14 | September 6 | | | 5 years in 10 earlier than----| October 4 | September 25 | September 16 | | | Carter County, Montana—Part I 11

Freeze Dates in Spring and Fall--Continued ______| | Temperature |______Probability | | | | 24 Degrees F | 28 Degrees F | 32 Degrees F | or Lower | or Lower | or Lower ______| | | | | | RIDGWAY: | | | | | | Last freezing temperature | | | in spring: January-July | | | | | | 1 year in 10 later than------| May 16 | May 24 | June 6 | | | 2 years in 10 later than------| May 10 | May 18 | May 31 | | | 5 years in 10 later than------| April 28 | May 8 | May 20 | | | First freezing temperature | | | in fall: August-December | | | | | | 1 year in 10 earlier than-----| September 16 | September 7 | August 26 | | | 2 years in 10 earlier than----| September 21 | September 12 | September 1 | | | 5 years in 10 earlier than----| October 3 | September 22 | September 11 ______| | | 12

Growing Season

(Recorded in the period 1964-1994 at Albion, Ekalaka, and Ridgway)

______| | Daily Minimum Temperature |______Probability | | | | Higher Than | Higher Than | Higher Than | 24 Degrees F | 28 Degrees F | 32 Degrees F ______| | | | Days | Days | Days | | | ALBION: | | | | | | 9 years in 10------| 126 | 104 | 86 | | | 8 years in 10------| 133 | 111 | 95 | | | 5 years in 10------| 148 | 125 | 112 | | | 2 years in 10------| 163 | 138 | 129 | | | 1 year in 10------| 170 | 145 | 138 | | | | | | EKALAKA: | | | | | | 9 years in 10------| 138 | 120 | 94 | | | 8 years in 10------| 146 | 128 | 102 | | | 5 years in 10------| 161 | 142 | 117 | | | 2 years in 10------| 177 | 157 | 132 | | | 1 year in 10------| 184 | 164 | 140 | | | | | | RIDGWAY: | | | | | | 9 years in 10------| 130 | 112 | 91 | | | 8 years in 10------| 139 | 121 | 99 | | | 5 years in 10------| 157 | 136 | 115 | | | 2 years in 10------| 175 | 152 | 130 | | | 1 year in 10------| 184 | 160 | 138 ______| | | 13

Formation and Classification of the Soils

This section relates the soils in the survey area to contain more organic matter and are dark colored. the major factors of soil formation and describes the Soils that have warm temperatures and low system of soil classification. The tables, precipitation, such as the Yamacall series, generally “Classification of the Soils” and “Acreage and contain less organic matter and are light colored. In Proportionate Extent of the Soils,” at the end of this Carter County, precipitation ranges from 10 to 19 section show the classification and extent of the soils inches annually. in this survey area. Living Organisms Formation of the Soils Living organisms are active in the formation of Soil is a natural, three-dimensional body on the soils. Among the earliest inhabitants of rock material, earth’s surface. Soil has properties that result from fungi and algae contribute to the decomposition of the integrated effect of climate and living matter bedrock. As rocks decompose, grasses, shrubs, and acting on earthy parent material, as conditioned by trees are able to grow and support animal life. relief over a period of time. Organic matter is the main source of the dark color Although there are many different soils, each soil of the surface layer. The kinds of plants and animals is the result of the interaction of the same five factors. in an area largely determine the kind and amount of These factors are the effect of climate on the parent organic matter added to the soil and the manner in material, the kinds of plants and organisms living in which this matter is incorporated into mineral parts of the soil, the relief of the land, the physical and the soil. Plants, animals, insects, and microorganisms chemical composition of the parent material, and the affect gains or losses in organic matter, plant length of time it took for the soil to form. nutrients, and changes in porosity and structure. Within short distances, the combination of these Roots, rodents, and insects penetrate the soil and factors varies, and, consequently, the soils that form influence its structure. Microorganisms, chemicals in differ in fertility, productivity, and physical and the soil, and insects change leaves, roots, and entire chemical characteristics. In the following paragraphs, plants that remain in the surface layer to humus. the factors of soil formation are discussed as they Animals increase porosity by burrowing through relate to the soils in the survey area. the soil and leaving open channels for the movement of water and air. Common burrowing animals are Climate badger, field mice, ground squirrel, prairie dog, and rabbit. Burrowing rodents brought up many of the Temperature and precipitation mainly determine pebbles and cobbles on the surface of terraces. climate, an active force in the formation of soils. Soils Native vegetation in Carter County consists mainly form in rocks that have been broken into suitable of short and mid grasses, forbs, and shrubs. materials by erosion and alternate freezing and thawing. Chemical reactions, such as solution and Topography hydration, further break down this weathered material. Water and wind are active agents in Topography, or relief, is determined by the transporting and separating weathered material. resistance of bedrock or soil material to water erosion Precipitation and temperature affect the kind and and soil blowing. Topography influences soil amount of vegetation that grows on the soil. development through its effect on drainage and Vegetation decays to produce organic matter in the runoff. On eroded uplands in the survey area, runoff soil. Soils that have cool temperatures and high water has carved deep intermittent drains with many precipitation, such as the Parshall series, generally branches into the original bedrock formations. This 14 Soil Survey

rugged relief contrasts sharply with the smooth low generally indicated by the thickness and distinctness relief of terraces and flood plains. of subsurface horizons, content of organic matter and On uplands, the number and distinctness of soil clay, depth to which soluble material is leached, and horizons generally decrease as the slope increases. form and distribution of calcium carbonate and Soils on steep slopes that have rapid runoff have gypsum in the soil. many characteristics similar to those of soils formed Havre loam, a soil of the Entisol order, is a young in arid climates. Nearly level to gently rolling soils soil that formed in alluvium on a flood plain. This soil have many characteristics similar to those of soils contains little organic matter with which to form an A formed in semiarid climates. Examples of these horizon. It has no clay accumulation and limited patterns, typical in Carter County, are the shallow translocation of carbonates has occurred to form Bk Blacksheep soil that has strongly sloping to steep horizons. slopes and no B horizon and the nearly level to gently Eapa loam formed in parent material similar to, but rolling Eapa soil that is very deep with a 7- to 24-inch much older than, that of the Havre soil. Eapa soil thick B horizon. formed in alluvium on alluvial fans and stream terraces and is a mature soil of the Mollisol order. It Parent Material contains enough organic matter to have a dark A horizon. Also, it has a distinct clay accumulation in Most soils in Carter County formed in place over the B horizon, and nearly all of the carbonates have semiconsolidated sedimentary beds or been leached below a depth of about 24 inches. semiconsolidated shale. Many soils formed in alluvium and were deposited in valleys. Soils, such as Classification of the Soils the Blacksheep series, that formed in material derived from semiconsolidated, sandy sedimentary The system of soil classification used by the beds are generally sandy. Soils, such as the Bascovy National Cooperative Soil Survey has six categories series, that formed in shale are clayey, since clay is (Soil Survey Staff, 1975 and 1990). Beginning with the basic constituent of shale. Soils, such as the the broadest, these categories are the order, Havre series, that formed in mixed alluvium derived suborder, great group, subgroup, family, and series. from semiconsolidated, loamy sedimentary beds are Classification is based on soil properties observed in loamy. the field or inferred from those observations or from Many soils in the county, such as the Alona series, laboratory measurements. The table, “Classification have acquired salt and sodium from their parent of the Soils,” shows the classification of the soils in materials. Salt and sodium make these soils saline or the survey area. The categories are defined in the alkaline and limit the kind and amount of plants able following paragraphs. to grow on them. The density of the parent rock and ORDER. Eleven soil orders are recognized. The its mineral composition can limit the rate of differences among orders reflect the dominant soil- weathering and the depth of a soil. forming processes and the degree of soil formation. Each order is identified by a word ending in sol. An Time example is Mollisol, from mollis, meaning soft. SUBORDER. Each order is divided into suborders Change taking place in soils over a long period is primarily on the basis of properties that influence soil called soil genesis. As a result of these changes, genesis and are important to plant growth or distinct horizons, or layers, develop in the soils. The properties that reflect the most important variables length of time that parent materials have been in within the orders. The last syllable in the name of a place and exposed to climate and living organisms is suborder indicates the order. An example is Boroll generally reflected in the degree to which the soil (Bor, meaning northern, plus oll, from Mollisol). profile has developed. The kind and arrangement of GREAT GROUP. Each suborder is divided into these horizons are called soil morphology. These great groups on the basis of close similarities in kind, layers are described in terms of chemistry, color, arrangement, and degree of development of consistence, permeability, structure, texture, and pedogenic horizons; soil moisture and temperature thickness. regimes; type of saturation; and base status. Each Soils are classified according to their approximate great group is identified by the name of a suborder age, from young to mature. Age or maturity of a soil is and by a prefix that indicates a property of the soil. Carter County, Montana—Part I 15

An example is Argiboroll (Argi, meaning having an properties and other characteristics that affect argillic or clay accumulation, plus boroll, the suborder management. Generally, the properties are those of of the Mollisols that are cool). horizons below plow depth where there is much SUBGROUP. Each great group has a typic biological activity. Among the properties and subgroup. Other subgroups are intergrades or characteristics considered are particle-size class, extragrades. The typic subgroup is the central mineral content, temperature regime, thickness of the concept of the great group; it is not necessarily the root zone, consistence, moisture equivalent, slope, most extensive. Intergrades are transitions to other and permanent cracks. A family name consists of the orders, suborders, or great groups. Extragrades have name of a subgroup preceded by terms that indicate some properties that are not representative of the soil properties. An example is Fine-loamy, mixed great group but do not indicate transitions to any Typic Argiborolls. other taxonomic class. Each subgroup is identified by SERIES. The series consists of soils within a family one or more adjectives preceding the name of the that have horizons similar in arrangement in the great group. The adjective Typic identifies the profile, color, consistence, mineral and chemical subgroup that typifies the great group. An example is composition, reaction, structure, and texture. An Typic Argiborolls. example is the Reeder series, which is a Fine-loamy, FAMILY. Families are established within a mixed Typic Argiboroll. subgroup on the basis of physical and chemical 23

Soil Series and Detailed Soil Map Units

In this section, arranged in alphabetical order, called noncontrasting, or similar, components. They each soil series recognized in the survey area is may or may not be mentioned in a particular map unit described. Each description is followed by the description. Other minor components, however, have detailed soil map units associated with the series. properties and behavioral characteristics divergent Characteristics of the soil and the material in which enough to affect use or to require different it formed are identified for each soil series. A pedon, management. These are called contrasting, or a small three-dimensional area of soil, that is typical dissimilar, components. They generally are in small of the series in the survey area is described. The areas and could not be mapped separately because detailed description of each soil horizon follows of the scale used. Some small areas of strongly standards in the “Soil Survey Manual” (Soil Survey contrasting soils or miscellaneous areas are Division Staff, 1962). Many of the technical terms identified by a special symbol on the maps. The used in the descriptions are defined in “Soil contrasting components are mentioned in the map Taxonomy” (Soil Survey Staff, 1975). Unless unit descriptions. A few areas of minor components otherwise stated, colors in the descriptions are for dry may not have been observed, and, consequently, soil. Following the pedon description is the range of they are not mentioned in the descriptions, especially important characteristics of the soils in the series. where the pattern was so complex that it was The map units delineated on the detailed soil impractical to make enough observations to identify maps in this survey represent the soils or all of the soils and miscellaneous areas on the miscellaneous areas in the survey area. The map unit landscape. descriptions in this section, along with the maps, can The presence of minor components in a map unit be used to determine the suitability and potential of a in no way diminishes the usefulness or accuracy of unit for specific uses. They also can be used to plan the data. The objective of mapping is not to delineate the management needed for those uses. pure taxonomic classes but rather to separate the A map unit delineation on a soil map represents an landscape into landforms or landform segments that area dominated by one or more major kinds of soil or have similar use and management requirements. The miscellaneous areas. A map unit is identified and delineation of such segments on the map provides named according to the taxonomic classification of sufficient information for the development of resource the dominant soils. Within a taxonomic class, there plans. If intensive use of small areas is planned, are precisely defined limits for the properties of the however, onsite investigation is needed to define and soils. On the landscape, however, the soils are locate the soils and miscellaneous areas. natural phenomena, and they have the characteristic An identifying symbol precedes the map unit name variability of all natural phenomena. Thus, the range in the map unit descriptions. Each description of some observed properties may extend beyond the includes general facts about the unit and gives the limits defined for a taxonomic class. Areas of soils of principal hazards and limitations to be considered in a single taxonomic class rarely, if ever, can be planning for specific uses. 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 24 Soil Survey

divided into soil phases. Most of the areas shown on Bss—4 to 14 inches; light brownish gray (2.5Y 6/2) the detailed soil maps are phases of soil series. The silty clay loam, dark grayish brown (2.5Y 4/2) name of a soil phase commonly indicates a feature moist; moderate medium prismatic structure that affects use or management. For example, parting to moderate fine and medium subangular Glendive sandy loam, saline, 0 to 4 percent slopes, is blocky; very hard, firm, very sticky, very plastic; a phase of the Glendive series. few very fine and fine roots; few slickensides; Some map units are made up of two or more major slightly effervescent; slightly alkaline; gradual soils or miscellaneous areas. These map units are wavy boundary. complexes, associations, or undifferentiated groups. Bssky—14 to 26 inches; light brownish gray (2.5Y This survey includes complexes. They consist of 6/2) silty clay loam, dark grayish brown (2.5Y 4/2) two or more soils or miscellaneous areas in such an moist; moderate medium prismatic structure intricate pattern or in such small areas that they parting to moderate medium subangular blocky; cannot be shown separately on the maps. The very hard, firm, very sticky, very plastic; few very pattern and proportion of the soils or miscellaneous fine roots; few slickensides; few fine nests and areas are somewhat similar in all areas. Gerdrum- seams of gypsum crystals; common fine masses Absher complex, warm, 3 to 9 percent slopes, is an of lime; strongly effervescent; moderately example. alkaline; gradual wavy boundary. This survey includes miscellaneous areas. They By—26 to 32 inches; light brownish gray (2.5Y 6/2) have little or no soil material and support little or no silty clay loam, dark grayish brown (2.5Y 4/2) vegetation. Badland is an example. moist; moderate medium subangular blocky The table, “Acreage and Proportionate Extent of structure; very hard, firm, very sticky, very plastic; the Soils,” in Parts I and II of the manuscript gives the few very fine roots; few fine masses and nests of acreage and proportionate extent of each map unit. gypsum; slightly effervescent; slightly alkaline; Other tables (see “Summary of Tables”) give gradual wavy boundary. properties of the soils and the limitations, capabilities, Cr—32 to 60 inches; light brownish gray (2.5Y 6/2) and potentials for many uses. Many of the terms used semiconsolidated shale that crushes to silty clay in describing the soils or miscellaneous areas are and silty clay loam, grayish brown (2.5Y 5/2) defined in the “Glossary.” moist.

Range in Characteristics Abor Series Soil temperature: 42 to 47 degrees F (60 to Depth class: Moderately deep (20 to 40 inches) 72 degrees F summer temperatures) Drainage class: Well drained Depth to the Bssky horizon: 10 to 16 inches Permeability: Very slow (<0.06 inch/hour) Depth to the Cr horizon: 20 to 40 inches 1 Landform: Sedimentary plains and hills Other features: When dry, this soil has /4- to 2-inch Parent material: Semiconsolidated shale cracks that extend to a depth of about 20 inches. Slope range: 2 to 15 percent A horizon Annual precipitation: 12 to 15 inches Hue: 10YR, 2.5Y, or 5Y Value: 5, 6, or 7 dry; 4, 5, or 6 moist Taxonomic Class: Fine, montmorillonitic, frigid Chroma: 1 to 4 (The 1 chroma is inherent from Leptic Udic Haplusterts the parent material.) Clay content: 35 to 40 percent Typical Pedon Content of rock fragments: 0 to 10 percent Abor silty clay loam, 2 to 8 percent slopes, in an area pebbles of rangeland, 2,000 feet north and 250 feet west of Electrical conductivity: 0 to 4 mmhos/cm the southeast corner of sec. 19, T. 6 S., R. 56 E. Reaction: pH 7.4 to 8.4 A—0 to 4 inches; light brownish gray (2.5Y 6/2) silty Bss horizon clay loam, dark grayish brown (2.5Y 4/2) moist; Hue: 10YR, 2.5Y, or 5Y moderate fine and medium granular structure; Value: 5, 6, or 7 dry; 4, 5, or 6 moist hard, friable, very sticky, very plastic; many very Chroma: 1 to 4 fine roots; slightly alkaline; clear smooth Texture: Silty clay, silty clay loam, or clay boundary. Clay content: 35 to 60 percent Carter County, Montana—Part I 25

Electrical conductivity: 0 to 4 mmhos/cm A typical soil description with range in Reaction: pH 7.4 to 9.0 characteristics is included, in alphabetical order, in this section. Bssky horizon Hue: 2.5Y, 5Y, 10YR, or 2.5YR Management Value: 5, 6, or 7 dry; 4 or 5 moist Chroma: 1 to 4 For management information about this map unit, Texture: Silty clay, silty clay loam, clay loam, or see appropriate sections in Part II of this publication. clay Clay content: 35 to 60 percent Slickensides: Few to common 251D—Abor-Yawdim silty clay loams, Electrical conductivity: 0 to 4 mmhos/cm 4 to 15 percent slopes Gypsum content: 1 to 5 percent Calcium carbonate equivalent: 5 to 15 percent Setting Reaction: pH 7.4 to 9.0 Landform: By horizon • Abor—Hills Hue: 2.5Y, 5Y, 10YR, or 2.5YR • Yawdim—Hills Value: 5, 6, or 7 dry; 4, 5, or 6 moist Position on landform: Chroma: 1 to 4 • Abor—Backslopes Texture: Silty clay, silty clay loam, or clay • Yawdim—Shoulders and summits Clay content: 35 to 60 percent Slope: Electrical conductivity: 0 to 4 mmhos/cm • Abor—4 to 15 percent Gypsum content: 1 to 5 percent • Yawdim—4 to 15 percent Calcium carbonate equivalent: 5 to 15 percent Mean annual precipitation: 12 to 15 inches Reaction: pH 7.4 to 9.0 Composition 51C—Abor silty clay loam, Major Components 2 to 8 percent slopes Abor and similar soils: 60 percent Yawdim and similar soils: 30 percent Setting Minor Components Bascovy and similar soils: 0 to 3 percent Landform: Sedimentary plains Marias and similar soils: 0 to 3 percent Slope: 2 to 8 percent Volborg and similar soils: 0 to 2 percent Mean annual precipitation: 12 to 15 inches Neldore and similar soils: 0 to 2 percent Composition Major Component Description Major Components Abor Abor and similar soils: 85 percent Surface layer texture: Silty clay loam Minor Components Depth class: Moderately deep (20 to 40 inches) Gerdrum and similar soils: 0 to 4 percent Drainage class: Well drained Marvan and similar soils: 0 to 4 percent Dominant parent material: Semiconsolidated shale Neldore and similar soils: 0 to 4 percent residuum Weingart and similar soils: 0 to 3 percent Native plant cover type: Rangeland Flooding: None Major Component Description Available water capacity: Mainly 4.6 inches Surface layer texture: Silty clay loam Depth class: Moderately deep (20 to 40 inches) Yawdim Drainage class: Well drained Surface layer texture: Silty clay loam Dominant parent material: Semiconsolidated shale Depth class: Shallow (10 to 20 inches) residuum Drainage class: Well drained Native plant cover type: Rangeland Dominant parent material: Semiconsolidated shale Flooding: None residuum Available water capacity: Mainly 4.9 inches Native plant cover type: Rangeland 26 Soil Survey

Flooding: None Bknyz—10 to 24 inches; light brownish gray (10YR Available water capacity: Mainly 2.5 inches 6/2) clay, dark grayish brown (10YR 4/2) moist; moderate coarse subangular blocky structure; A typical soil description with range in very hard, firm, moderately sticky, moderately characteristics is included, in alphabetical order, plastic; few very fine roots; few very fine pores; in this section. common very fine and fine nests and seams of gypsum crystals; few fine seams of other salts; Management few fine masses of lime; violently effervescent; moderately alkaline; gradual wavy boundary. For management information about this map unit, Bkyz—24 to 60 inches; very pale brown (10YR 7/3) see appropriate sections in Part II of this publication. clay, dark grayish brown (10YR 4/2) moist; massive; very hard, firm, moderately sticky, Absher Series moderately plastic; common very fine and fine nests of gypsum crystals; few very fine and fine Depth class: Very deep (more than 60 inches) seams of other salts; few fine masses of lime; Drainage class: Moderately well drained strongly effervescent; moderately alkaline. Permeability: Very slow (<0.06 inch/hour) Range in Characteristics Landform: Alluvial fans and stream terraces Parent material: Alluvium Soil temperature: 42 to 47 degrees F (60 to Slope range: 0 to 9 percent 68 degrees F summer temperatures) Annual precipitation: 12 to 15 inches Depth to the Bknyz horizon: 6 to 20 inches Other features: In areas that are cultivated, a clay Taxonomic Class: Fine, montmorillonitic Typic texture results from mixing the E and Bt horizons. Natriboralfs Taxonomic note: Map units 611B and 611D are taxadjuncts to the Absher series in order to join Typical Pedon soils that have an average soil temperature Absher clay, in an area of Absher-Gerdrum complex, greater than 47 degrees F. 0 to 4 percent slopes, in an area of rangeland, E horizon 650 feet north and 1,250 feet east of the southwest Hue: 2.5Y, 10YR, or 7.5YR corner of sec. 25, T. 9 S., R. 59 E. Value: 6 or 7 dry; 3, 4, or 5 moist E—0 to 1 inch; pale brown (10YR 6/3) fine sandy Chroma: 1 to 3 loam, brown (10YR 4/3) moist; moderate thin Texture: Clay when mixed to 7 inches platy structure parting to weak fine granular; soft, Clay content: 15 to 20 percent very friable, nonsticky, nonplastic; common very Electrical conductivity: 4 to 8 mmhos/cm fine and fine roots; common very fine tubular Reaction: pH 6.6 to 8.4 pores; slightly alkaline; abrupt smooth boundary. Btn1 horizon Btn1—1 to 7 inches; light brownish gray (10YR 6/2) Hue: 2.5Y, 10YR, or 7.5YR clay, brown (10YR 5/3) moist; moderate medium Value: 4, 5, or 6 dry; 4 or 5 moist columnar structure parting to strong fine and Chroma: 1 to 3 medium subangular blocky; very hard, firm, Texture: Silty clay, clay, or clay loam moderately sticky, moderately plastic; few fine Clay content: 35 to 60 percent and many very fine roots; few very fine and fine Content of rock fragments: 0 to 15 percent pores; common faint clay films on faces of peds pebbles and in pores; moderately alkaline; clear smooth Electrical conductivity: 8 to 16 mmhos/cm boundary. Sodium adsorption ratio: 18 to 70 Btn2—7 to 10 inches; pale brown (10YR 6/3) clay, Reaction: pH 6.6 to 8.4 brown (10YR 4/3) moist; moderate fine and medium subangular blocky structure; very hard, Btn2 horizon very firm, moderately sticky, moderately plastic; Hue: 2.5Y, 10YR, or 7.5YR few very fine and fine roots; few very fine pores; Value: 4, 5, or 6 dry; 4 or 5 moist common faint clay films on faces of peds and in Chroma: 1 to 3 pores; strongly effervescent; moderately alkaline; Texture: Silty clay, clay, or clay loam clear smooth boundary. Clay content: 35 to 60 percent Carter County, Montana—Part I 27

Content of rock fragments: 0 to 15 percent Native plant cover type: Rangeland pebbles Flooding: None Electrical conductivity: 4 to 8 mmhos/cm Salt affected: Saline within 30 inches Sodium adsorption ratio: 18 to 70 Sodium affected: Sodic within 30 inches Reaction: pH 6.6 to 8.4 Available water capacity: Mainly 4.1 inches Bknyz and Bkyz horizons Gerdrum Hue: 2.5Y, 10YR, or 7.5YR Surface layer texture: Clay loam Value: 5, 6, or 7 dry; 4, 5, or 6 moist Depth class: Very deep (more than 60 inches) Chroma: 2 to 4 Drainage class: Well drained Texture: Clay loam, sandy clay loam, silty clay, Dominant parent material: Alluvium clay, or silty clay loam Native plant cover type: Rangeland Clay content: 27 to 50 percent Flooding: None Content of rock fragments: 0 to 15 percent Salt affected: Saline within 30 inches pebbles Sodium affected: Sodic within 30 inches Calcium carbonate equivalent: 4 to 15 percent Available water capacity: Mainly 6.1 inches Electrical conductivity: 16 to 30 mmhos/cm Sodium adsorption ratio: 18 to 70 A typical soil description with range in Gypsum content: 1 to 5 percent characteristics is included, in alphabetical order, Reaction: pH 7.9 to 9.6 in this section. Management 168B—Absher-Gerdrum complex, 0 to 4 percent slopes For management information about this map unit, see appropriate sections in Part II of this publication. Setting Landform: • Absher—Alluvial fans and stream terraces Alona Series • Gerdrum—Alluvial fans and stream terraces Depth class: Very deep (more than 60 inches) Position on landform: Drainage class: Well drained • Absher—Microlows Permeability: Moderately slow (0.2 to 0.6 inch/hour) • Gerdrum—Microhighs Landform: Alluvial fans and stream terraces Slope: Parent material: Alluvium • Absher—0 to 4 percent Slope range: 2 to 8 percent • Gerdrum—0 to 4 percent Annual precipitation: 12 to 15 inches Mean annual precipitation: 12 to 15 inches Composition Taxonomic Class: Fine-silty, mixed, frigid Aridic Ustochrepts Major Components Absher and similar soils: 60 percent Typical Pedon Gerdrum and similar soils: 30 percent Alona silt loam, 2 to 8 percent slopes, in an area of Minor Components rangeland, 800 feet north and 1,000 feet east of the Creed and similar soils: 0 to 3 percent southwest corner of sec. 1, T. 8 S., R. 59 E. Marvan and similar soils: 0 to 3 percent Soils that have slopes more than 4 percent: 0 to A—0 to 3 inches; light brownish gray (2.5Y 6/2) silt 1 2 percent loam, dark grayish brown (2.5Y 4/2) moist; /2- to Very deep nonsaline soils: 0 to 2 percent 1-inch vesicular crust over moderate fine and medium granular structure; slightly hard, friable, Major Component Description slightly sticky, slightly plastic; common very fine Absher roots; common very fine tubular pores; slightly Surface layer texture: Clay effervescent; slightly alkaline; clear smooth Depth class: Very deep (more than 60 inches) boundary. Drainage class: Moderately well drained Bw—3 to 10 inches; light brownish gray (2.5Y 6/2) silt Dominant parent material: Alluvium loam, dark grayish brown (2.5 4/2) moist; 28 Soil Survey

moderate medium subangular blocky structure; Chroma: 2 to 4 hard, friable, moderately sticky, moderately Texture: Silt loam or silty clay loam plastic; common very fine roots; many very fine Clay content: 18 to 35 percent tubular pores; strongly effervescent; strongly Calcium carbonate equivalent: 5 to 15 percent alkaline; gradual wavy boundary. Electrical conductivity: 8 to 16 mmhos/cm Bk—10 to 22 inches; light brownish gray (2.5Y 6/2) Sodium adsorption ratio: 13 to 40 silty clay loam, dark grayish brown (2.5Y 4/2) Reaction: pH 9.1 to 9.6 moist; moderate medium and coarse subangular Bkz horizon blocky structure; hard, friable, moderately sticky, Hue: 10YR, 2.5Y, or 5Y moderately plastic; few very fine roots; common Value: 6 or 7 dry; 4, 5, or 6 moist very fine tubular pores; common very fine Chroma: 2 to 4 masses of lime; violently effervescent; strongly Texture: Loam, silty clay loam, or silt loam alkaline; clear smooth boundary. Clay content: 18 to 35 percent Bkz—22 to 60 inches; light brownish gray (2.5Y 6/2) Calcium carbonate equivalent: 5 to 15 percent silty clay loam, dark grayish brown (2.5Y 4/2) Electrical conductivity: 8 to 16 mmhos/cm moist; moderate medium subangular blocky Sodium adsorption ratio: 13 to 40 structure; hard, friable, moderately sticky, Reaction: pH 8.5 to 9.6 moderately plastic; few very fine roots; few very fine pores; few fine nests and seams of salt crystals; common fine and medium masses of 20C—Alona silt loam, lime; violently effervescent; strongly alkaline. 2 to 8 percent slopes Range in Characteristics Setting Soil temperature: 42 to 47 degrees F Depth to the Bk horizon: 6 to 18 inches Landform: Alluvial fans and stream terraces Soil phases: Warm Slope: 2 to 8 percent Taxonomic note: Map unit 621C is a taxadjunct to Mean annual precipitation: 12 to 15 inches the Alona series in order to join soils that have Composition an average soil temperature greater than 47 degrees F. Major Components Alona and similar soils: 85 percent A horizon Hue: 10YR or 2.5Y Minor Components Value: 5 or 6 dry; 3, 4, or 5 moist Cambeth and similar soils: 0 to 4 percent Chroma: 2 or 3 Soils that have darker colored surface layers: 0 to Clay content: 18 to 27 percent 4 percent Electrical conductivity: 2 to 4 mmhos/cm Very deep nonsaline soils: 0 to 4 percent Sodium adsorption ratio: 2 to 10 Soils that have slopes more than 8 percent: 0 to Calcium carbonate equivalent: 5 to 10 percent 3 percent Reaction: pH 7.4 to 8.4 Major Component Description Bw horizon Surface layer texture: Silt loam Hue: 10YR or 2.5Y Depth class: Very deep (more than 60 inches) Value: 5 or 6 dry; 3, 4, or 5 moist Drainage class: Well drained Chroma: 2 to 4 Dominant parent material: Alluvium Texture: Silt loam or silty clay loam Native plant cover type: Rangeland Clay content: 18 to 35 percent Flooding: None Electrical conductivity: 2 to 8 mmhos/cm Salt affected: Saline within 30 inches Sodium adsorption ratio: 13 to 40 Sodium affected: Sodic within 30 inches Calcium carbonate equivalent: 5 to 10 percent Available water capacity: Mainly 6.2 inches Reaction: pH 8.5 to 9.6 Bk horizon A typical soil description with range in Hue: 10YR, 2.5Y, or 5Y characteristics is included, in alphabetical order, Value: 6 or 7 dry; 4, 5, or 6 moist in this section. Carter County, Montana—Part I 29

Management Slope range: 2 to 8 percent Annual precipitation: 12 to 15 inches For management information about this map unit, Taxonomic Class: Fine, mixed, frigid Aridic see appropriate sections in Part II of this publication. Ustochrepts Typical Pedon 621C—Alona silt loam, warm, 2 to 8 percent slopes Alzada clay loam, 2 to 8 percent slopes, in an area of rangeland, 2,200 feet north and 2,500 feet west of the southeast corner of sec. 24, T. 9 S., R. 58 E. Setting A—0 to 2 inches; light brownish gray (10YR 6/2) Landform: Alluvial fans and stream terraces sandy clay loam, dark grayish brown (10YR 4/2) Slope: 2 to 8 percent moist; moderate fine and medium subangular Mean annual precipitation: 12 to 15 inches blocky structure; slightly hard, friable, slightly Composition sticky, slightly plastic; common very fine roots; slightly acid; clear smooth boundary. Major Components Bw—2 to 10 inches; brown (10YR 5/3) clay, dark Alona and similar soils: 85 percent grayish brown (10YR 4/2) moist; weak medium Minor Components prismatic structure parting to moderate fine and Moderately deep loamy soils: 0 to 4 percent medium subangular blocky; hard, firm, very Soils that have slopes more than 8 percent: 0 to sticky, very plastic; common very fine roots; few 4 percent very fine and fine pores; common faint clay films Very deep, nonsaline soils: 0 to 4 percent on faces of peds and in pores; disseminated lime; Soils that have darker colored surface layers: 0 to slightly effervescent; slightly alkaline; gradual 3 percent smooth boundary. Bk—10 to 16 inches; grayish brown (10YR 5/2) clay, Major Component Description dark grayish brown (10YR 4/2) moist; moderate Surface layer texture: Silt loam fine and medium subangular blocky structure; Depth class: Very deep (more than 60 inches) hard, friable, moderately sticky, very plastic; Drainage class: Well drained common very fine roots; few fine masses of lime; Dominant parent material: Alluvium strongly effervescent; moderately alkaline; Native plant cover type: Rangeland gradual smooth boundary. Flooding: None 2Bkyz—16 to 36 inches; gray (10YR 5/1) silty clay Salt affected: Saline within 30 inches loam, very dark gray (10YR 3/1) moist; weak Sodium affected: Sodic within 30 inches medium prismatic structure; hard, firm, Available water capacity: Mainly 6.2 inches moderately sticky, moderately plastic; many fine and medium nests and seams of gypsum A typical soil description with range in crystals; few fine seams of other salts; few fine characteristics is included, in alphabetical order, seams of lime; strongly effervescent; neutral; in this section. gradual wavy boundary. 2C—36 to 60 inches; gray (10YR 5/1) clay, very dark Management gray (10YR 3/1) moist; massive; hard, firm, moderately sticky, moderately plastic; neutral. For management information about this map unit, see appropriate sections in Part II of this publication. Range in Characteristics Soil temperature: 43 to 47 degrees F Depth to the Bk horizon: 8 to 16 inches Alzada Series Depth to the 2Bkyz horizon: 12 to 22 inches Depth class: Very deep (more than 60 inches) A horizon Drainage class: Well drained Hue: 10YR or 2.5Y Permeability: Slow (0.06 to 0.2 inch/hour) Value: 6 or 7 dry; 3, 4, or 5 moist Landform: Alluvial fans and stream terraces Chroma: 2 or 3 Parent material: Alluvium Texture: Clay loam when mixed to 7 inches 30 Soil Survey

Clay content: 27 to 35 percent Minor Components Electrical conductivity: 0 to 2 mmhos/cm Gerdrum and similar soils: 0 to 3 percent Reaction: pH 5.6 to 7.3 Neldore and similar soils: 0 to 3 percent Teigen and similar soils: 0 to 3 percent Bw horizon Very shallow soils: 0 to 3 percent Hue: 10YR or 2.5Y Soils that have slopes less than 2 percent: 0 to Value: 5 or 6 dry; 4 or 5 moist 3 percent Chroma: 2 to 4 Texture: Silty clay loam or clay Major Component Description Clay content: 35 to 50 percent Electrical conductivity: 0 to 2 mmhos/cm Surface layer texture: Clay loam Sodium adsorption ratio: 0 to 13 Depth class: Very deep (more than 60 inches) Reaction: pH 7.4 to 8.4 Drainage class: Well drained Dominant parent material: Alluvium Bk horizon Native plant cover type: Rangeland Hue: 10YR or 2.5Y Flooding: None Value: 5 or 6 dry; 4 or 5 moist Available water capacity: Mainly 8.4 inches Chroma: 2 to 4 Texture: Silty clay loam or clay A typical soil description with range in Clay content: 35 to 50 percent characteristics is included, in alphabetical order, Electrical conductivity: 0 to 2 mmhos/cm in this section. Sodium adsorption ratio: 0 to 13 Calcium carbonate equivalent: 5 to 15 percent Management Reaction: pH 7.4 to 8.4 For management information about this map unit, 2Bkyz horizon see appropriate sections in Part II of this publication. Hue: 10YR or 2.5Y Value: 5 or 6 dry; 3 or 4 moist Chroma: 1 or 2 Texture: Silty clay loam or clay Archin Series Clay content: 35 to 50 percent Depth class: Very deep (more than 60 inches) Electrical conductivity: 4 to 8 mmhos/cm Drainage class: Well drained Gypsum content: 1 to 5 percent Permeability: Slow (0.06 to 0.2 inch/hour) Reaction: pH 6.6 to 8.4 Landform: Alluvial fans, stream terraces, and 2C horizon sedimentary plains Hue: 10YR or 2.5Y Parent material: Alluvium Value: 5 or 6 dry; 3 or 4 moist Slope range: 0 to 8 percent Chroma: 1 or 2 Annual precipitation: 12 to 15 inches Texture: Clay loam, silty clay loam, or clay Clay content: 35 to 50 percent Taxonomic Class: Fine-loamy, mixed Borollic Electrical conductivity: 4 to 8 mmhos/cm Natrargids Reaction: pH 6.6 to 8.4 Typical Pedon Archin fine sandy loam, in an area of Archin-Absher 92C—Alzada clay loam, complex, 2 to 8 percent slopes, in an area of 2 to 8 percent slopes rangeland, 1,700 feet south and 650 feet east of the northwest corner of sec. 14, T. 3 N., R. 56 E. Setting A—0 to 4 inches; pale brown (10YR 6/3) fine sandy Landform: Alluvial fans and stream terraces loam, brown (10YR 4/3) moist; weak fine granular Slope: 2 to 8 percent structure; soft, very friable, slightly sticky, slightly Mean annual precipitation: 12 to 15 inches plastic; many very fine roots; many very fine pores; neutral; clear smooth boundary. Composition E—4 to 7 inches; very pale brown (10YR 7/3) loam, Major Components dark grayish brown (10YR 4/2) moist; weak Alzada and similar soils: 85 percent medium subangular blocky structure parting to Carter County, Montana—Part I 31

weak fine granular; slightly hard, very friable, Btn horizon slightly sticky, slightly plastic; many very fine Hue: 10YR or 2.5Y roots; few fine and common very fine pores; Value: 5 or 6 dry; 4 or 5 moist neutral; abrupt smooth boundary. Chroma: 2 to 4 Btn—7 to 20 inches; light yellowish brown (2.5Y 6/4) Texture: Loam or clay loam clay loam, dark grayish brown (2.5Y 4/2) moist; Clay content: 25 to 34 percent moderate medium prismatic structure parting to Electrical conductivity: 0 to 4 mmhos/cm strong medium subangular blocky; hard, very Sodium adsorption ratio: 13 to 20 firm, very sticky, moderately plastic; common very Reaction: pH 6.6 to 8.4 fine and fine roots; many very fine pores; many Bky horizon faint clay films on faces of peds and in pores; Value: 5, 6, or 7 dry; 4, 5, or 6 moist moderately alkaline; clear smooth boundary. Chroma: 1 to 4 Bky—20 to 28 inches; light gray (2.5Y 7/2) loam, Texture: Loam or clay loam grayish brown (2.5Y 5/2) moist; moderate Clay content: 20 to 35 percent medium and coarse subangular blocky structure; Electrical conductivity: 4 to 8 mmhos/cm slightly hard, firm, slightly sticky, moderately Sodium adsorption ratio: 13 to 20 plastic; few very fine roots; common fine nests Calcium carbonate equivalent: 5 to 15 percent and seams of gypsum crystals; many fine and Gypsum content: 1 to 5 percent medium masses of lime; strongly alkaline; clear Reaction: pH 7.4 to 9.0 smooth boundary. BC—28 to 34 inches; light brownish gray (2.5Y 6/2) BC horizon loam, dark grayish brown (2.5Y 4/2) moist; weak Value: 5, 6, or 7 dry; 4, 5, or 6 moist medium and coarse subangular blocky structure; Chroma: 1 to 4 hard, friable, slightly sticky, slightly plastic; Texture: Loam or clay loam strongly alkaline; gradual smooth boundary. Clay content: 20 to 35 percent C—34 to 60 inches; light brownish gray (2.5Y 6/2) Electrical conductivity: 4 to 8 mmhos/cm loam, dark grayish brown (2.5Y 4/2) moist; Sodium adsorption ratio: 13 to 20 massive; hard, friable, slightly sticky, slightly Reaction: pH 7.4 to 9.0 plastic; strongly alkaline. C horizon Value: 5, 6, or 7 dry; 4, 5, or 6 moist Range in Characteristics Chroma: 1 to 4 Texture: Loam or clay loam Depth to the Bky horizon: 12 to 30 inches Clay content: 20 to 30 percent Soil phases: Gullied Electrical conductivity: 4 to 16 mmhos/cm Other features: Some pedons have a Bkz horizon. Sodium adsorption ratio: 13 to 20 Taxonomic note: The Archin soil is a taxadjunct to the Reaction: pH greater than 8.4 series. It classifies as Fine-loamy, mixed Typic Natriboralfs. Use and management is similar. A horizon 75A—Archin-Absher complex, Hue: 10YR or 2.5Y 0 to 2 percent slopes Value: 5 or 6 dry; 4 or 5 moist Chroma: 1 to 3 Setting Texture: Loam or fine sandy loam Landform: Clay content: 10 to 25 percent • Archin—Alluvial fans and stream terraces Reaction: pH 6.1 to 7.3 • Absher—Alluvial fans and stream terraces E horizon Position on landform: Hue: 10YR or 2.5Y • Archin—Microhighs Value: 5, 6, or 7 dry; 3, 4, or 5 moist • Absher—Microlows Chroma: 1 to 3 Slope: Texture: Loam or fine sandy loam • Archin—0 to 2 percent Clay content: 10 to 25 percent • Absher—0 to 2 percent Reaction: pH 6.1 to 7.3 Mean annual precipitation: 12 to 15 inches 32 Soil Survey

Composition Position on landform: • Archin—Microhighs Major Components • Absher—Microlows Archin and similar soils: 50 percent Slope: Absher and similar soils: 35 percent • Archin—2 to 8 percent Minor Components • Absher—2 to 8 percent Chinook and similar soils: 0 to 3 percent Mean annual precipitation: 12 to 15 inches Cambeth and similar soils: 0 to 3 percent Very deep, nonsaline soils: 0 to 3 percent Composition Soils that have darker colored surface layers: 0 to 2 percent Major Components Busby and similar soils: 0 to 2 percent Archin and similar soils: 50 percent Soils that have slopes more than 2 percent: 0 to Absher and similar soils: 35 percent 2 percent Minor Components Major Component Description Chinook and similar soils: 0 to 3 percent Busby and similar soils: 0 to 3 percent Archin Cambeth and similar soils: 0 to 3 percent Surface layer texture: Fine sandy loam Very deep, nonsaline soils: 0 to 2 percent Depth class: Very deep (more than 60 inches) Soils that have slopes more than 8 percent: 0 to Drainage class: Well drained 2 percent Dominant parent material: Alluvium Soils with darker colored surface layers: 0 to Native plant cover type: Rangeland 2 percent Flooding: None Salt affected: Saline within 30 inches Major Component Description Sodium affected: Sodic within 30 inches Available water capacity: Mainly 6.6 inches Archin Surface layer texture: Fine sandy loam Absher Depth class: Very deep (more than 60 inches) Surface layer texture: Clay loam Drainage class: Well drained Depth class: Very deep (more than 60 inches) Dominant parent material: Alluvium Drainage class: Moderately well drained Native plant cover type: Rangeland Dominant parent material: Alluvium Flooding: None Native plant cover type: Rangeland Salt affected: Saline within 30 inches Flooding: None Sodium affected: Sodic within 30 inches Salt affected: Saline within 30 inches Available water capacity: Mainly 6.6 inches Sodium affected: Sodic within 30 inches Available water capacity: Mainly 4.3 inches Absher Surface layer texture: Clay loam A typical soil description with range in Depth class: Very deep (more than 60 inches) characteristics is included, in alphabetical order, Drainage class: Moderately well drained in this section. Dominant parent material: Alluvium Management Native plant cover type: Rangeland Flooding: None For management information about this map unit, Salt affected: Saline within 30 inches see appropriate sections in Part II of this publication. Sodium affected: Sodic within 30 inches Available water capacity: Mainly 4.1 inches

75C—Archin-Absher complex, A typical soil description with range in 2 to 8 percent slopes characteristics is included, in alphabetical order, in this section. Setting Management Landform: • Archin—Alluvial fans and stream terraces For management information about this map unit, • Absher—Alluvial fans and stream terraces see appropriate sections in Part II of this publication. Carter County, Montana—Part I 33

175A—Archin loam, 0 to 2 percent slopes Parchin and similar soils: 0 to 3 percent Very deep, nonsaline soils: 0 to 3 percent Areas of slickspots: 0 to 2 percent Setting Soils that have slopes more than 8 percent: 0 to Landform: Alluvial fans and stream terraces 1 percent Slope: 0 to 2 percent Major Component Description Mean annual precipitation: 12 to 15 inches Surface layer texture: Loam Composition Depth class: Very deep (more than 60 inches) Major Components Drainage class: Well drained Archin and similar soils: 85 percent Dominant parent material: Alluvium Native plant cover type: Rangeland Minor Components Flooding: None Absher and similar soils: 0 to 3 percent Sodium affected: Sodic within 30 inches Chinook and similar soils: 0 to 3 percent Available water capacity: Mainly 7.9 inches Soils that have slopes more than 2 percent: 0 to 3 percent A typical soil description with range in Very deep, nonsaline soils: 0 to 2 percent characteristics is included, in alphabetical order, Soils that have darker colored surface layers: 0 to in this section. 2 percent Areas of slickspots: 0 to 2 percent Management Major Component Description For management information about this map unit, Surface layer texture: Loam see appropriate sections in Part II of this publication. Depth class: Very deep (more than 60 inches) Drainage class: Well drained Dominant parent material: Alluvium 275D—Archin, gullied-Delpoint complex, Native plant cover type: Rangeland 4 to 15 percent slopes Flooding: None Sodium affected: Sodic within 30 inches Setting Available water capacity: Mainly 7.9 inches Landform: A typical soil description with range in • Archin—Sedimentary plains characteristics is included, in alphabetical order, • Delpoint—Hills in this section. Position on landform: • Archin—Footslopes and toeslopes Management • Delpoint—Shoulders and summits Slope: For management information about this map unit, • Archin—4 to 8 percent see appropriate sections in Part II of this publication. • Delpoint—4 to 15 percent Mean annual precipitation: 12 to 15 inches 175C—Archin loam, 2 to 8 percent slopes Composition Major Components Setting Archin and similar soils: 45 percent Landform: Alluvial fans and stream terraces Delpoint and similar soils: 40 percent Slope: 2 to 8 percent Minor Components Mean annual precipitation: 12 to 15 inches Very deep nonsaline soils: 0 to 3 percent Composition Gerdrum and similar soils: 0 to 3 percent Yawdim and similar soils: 0 to 3 percent Major Components Soils that have slopes more than 15 percent: 0 to Archin and similar soils: 85 percent 2 percent Minor Components Soils that have slopes less than 4 percent: 0 to Absher and similar soils: 0 to 3 percent 2 percent Chinook and similar soils: 0 to 3 percent Very deep, silt loam soils: 0 to 2 percent 34 Soil Survey

Major Component Description Yamacall and similar soils: 0 to 3 percent Areas of slickspots: 0 to 3 percent Archin Surface layer texture: Fine sandy loam Major Component Description Depth class: Very deep (more than 60 inches) Archin Drainage class: Well drained Surface layer texture: Fine sandy loam Dominant parent material: Alluvium Depth class: Very deep (more than 60 inches) Native plant cover type: Rangeland Drainage class: Well drained Flooding: None Dominant parent material: Alluvium Salt affected: Saline within 30 inches Native plant cover type: Rangeland Sodium affected: Sodic within 30 inches Flooding: None Available water capacity: Mainly 6.6 inches Sodium affected: Sodic within 30 inches Available water capacity: Mainly 8.2 inches Delpoint Surface layer texture: Loam Ynot Depth class: Moderately deep (20 to 40 inches) Surface layer texture: Sandy loam Drainage class: Well drained Depth class: Very deep (more than 60 inches) Dominant parent material: Semiconsolidated, loamy Drainage class: Well drained sedimentary beds Dominant parent material: Alluvium Native plant cover type: Rangeland Native plant cover type: Rangeland Flooding: None Flooding: None Available water capacity: Mainly 4.7 inches Available water capacity: Mainly 7.7 inches A typical soil description with range in A typical soil description with range in characteristics is included, in alphabetical order, characteristics is included, in alphabetical order, in this section. in this section. 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.

375C—Archin-Ynot complex, Arsite Series 2 to 8 percent slopes Depth class: Shallow (10 to 20 inches) Drainage class: Well drained Setting Permeability: Very slow (less than 0.06 inch/hour) Landform: Landform: Sedimentary plains and hills • Archin—Alluvial fans and stream terraces Parent material: Alluvium or semiconsolidated shale • Ynot—Alluvial fans and stream terraces Slope range: 0 to 25 percent Slope: Annual precipitation: 12 to 15 inches • Archin—2 to 8 percent • Ynot—2 to 8 percent Taxonomic Class: Clayey, montmorillonitic, nonacid, Mean annual precipitation: 12 to 15 inches frigid, shallow Aridic Ustorthents Composition Typical Pedon Major Components Arsite clay, 0 to 8 percent slopes, in an area of Archin and similar soils: 45 percent rangeland, 2,100 feet south and 550 feet east of the Ynot and similar soils: 40 percent northwest corner of sec. 9, T. 2 S., R. 58 E. Minor Components A—0 to 2 inches; light brownish gray (10YR 6/2) Absher and similar soils: 0 to 3 percent sandy clay loam, dark grayish brown (10YR 4/2) Cambeth and similar soils: 0 to 3 percent moist; strong fine subangular blocky structure 1 Busby and similar soils: 0 to 3 percent with /2-inch thick vesicular crust on surface; Carter County, Montana—Part I 35

slightly hard, very friable, slightly sticky, slightly 79C—Arsite clay, 0 to 8 percent slopes plastic; common very fine and fine roots; neutral; clear wavy boundary. Setting Cyz1—2 to 6 inches; light brownish gray (10YR 6/2) clay, dark grayish brown (10YR 4/2) moist; strong Landform: Sedimentary plains coarse prismatic structure; hard, firm, moderately Slope: 0 to 8 percent sticky, moderately plastic; common very fine and Mean annual precipitation: 12 to 15 inches fine roots; common fine masses and seams of gypsum crystals; few very fine seams of other Composition salts; slightly acid; clear wavy boundary. Cyz2—6 to 12 inches; light brownish gray (10YR 6/2) Major Components clay, very dark grayish brown (10YR 3/2) moist; Arsite and similar soils: 85 percent massive; slightly hard, firm, moderately sticky, Minor Components moderately plastic; common very fine and fine Bascovy and similar soils: 0 to 4 percent roots; 30 percent soft shale fragments; common Neldore and similar soils: 0 to 4 percent medium masses of gypsum crystals; few fine and Vaeda and similar soils: 0 to 4 percent medium masses and seams of other salts; few Marvan and similar soils: 0 to 3 percent thin horizontal iron stains and few small masses of sulfur; moderately acid; clear wavy boundary. Major Component Description Cr—12 to 60 inches; grayish brown (10YR 5/2) semiconsolidated shale that crushes to clay, very Surface layer texture: Clay dark grayish brown (10YR 3/2) moist. Depth class: Shallow (10 to 20 inches) Range in Characteristics Drainage class: Well drained Dominant parent material: Semiconsolidated shale Soil temperature: 43 to 47 degrees F residuum Depth to the Cr horizon: 10 to 20 inches Native plant cover type: Rangeland A horizon Flooding: None Hue: 10YR or 2.5Y Salt affected: Saline within 30 inches Value: 6 or 7 dry; 4 or 5 moist Available water capacity: Mainly 1.0 inches Chroma: 2 or 3 Texture: Clay when mixed to 7 inches A typical soil description with range in Clay content: 15 to 30 percent characteristics is included, in alphabetical order, Electrical conductivity: 8 to 16 mmhos/cm in this section. Reaction: pH 6.1 to 7.8 Management Cyz1 horizon Hue: 10YR or 2.5Y For management information about this map unit, Value: 5 or 6 dry; 3 or 4 moist see appropriate sections in Part II of this publication. Chroma: 2 or 3 Texture: Clay or silty clay Clay content: 40 to 60 percent 179E—Arsite-Rock outcrop complex, Electrical conductivity: 8 to 16 mmhos/cm 8 to 25 percent slopes Reaction: pH 5.6 to 7.3 Cyz2 horizon Setting Hue: 10YR, 2.5Y, or 5Y Value: 5 or 6 dry; 3, 4, or 5 moist Landform: Chroma: 2 or 3 • Arsite—Hills Texture: Silty clay or clay • Rock outcrop—Hills Clay content: 40 to 60 percent Position on landform: Content of rock fragments: 30 to 50 percent soft • Arsite—Backslopes and footslopes shale fragments • Rock outcrop—Summits Electrical conductivity: 8 to 16 mmhos/cm Slope: 8 to 25 percent Reaction: pH 5.6 to 7.8 Mean annual precipitation: 12 to 15 inches 36 Soil Survey

Composition fine granular structure; loose, friable, nonsticky, nonplastic; few fine and medium and many very Major Components fine roots; neutral; clear smooth boundary. Arsite and similar soils: 45 percent Bt1—3 to 16 inches; grayish brown (10YR 5/3) sandy Rock outcrop: 40 percent clay loam, dark brown (10YR 3/3) moist; Minor Components moderate medium prismatic structure parting to Bascovy and similar soils: 0 to 5 percent moderate medium subangular blocky; hard, Neldore and similar soils: 0 to 5 percent friable, slightly sticky, slightly plastic; many very Very shallow clayey soils: 0 to 5 percent fine roots; common distinct clay films on faces of peds and in pores; neutral; clear smooth Major Component Description boundary. Arsite Bt2—16 to 23 inches; light yellowish brown (10YR Surface layer texture: Clay 6/4) sandy clay loam, yellowish brown (10YR 5/4) Depth class: Shallow (10 to 20 inches) moist; weak coarse prismatic structure parting to Drainage class: Well drained moderate medium subangular blocky; hard, Dominant parent material: Alluvium friable, slightly sticky, slightly plastic; common Native plant cover type: Rangeland very fine, fine, and medium roots; many distinct Flooding: None clay films on faces of peds and in pores; slightly Salt affected: Saline within 30 inches alkaline; clear smooth boundary. Available water capacity: Mainly 1.0 inches Btk—23 to 32 inches; pale brown (10YR 6/3) sandy loam, brown (10YR 5/3) moist; moderate medium Rock outcrop subangular blocky structure; slightly hard, friable, Definition: Consolidated shale nonsticky, nonplastic; few very fine roots; few very fine and fine pores; few faint clay films on faces of A typical soil description with range in ped and in pores; few fine seams of lime; slightly characteristics is included, in alphabetical order, effervescent; slightly alkaline; gradual smooth in this section. boundary. Bk—32 to 42 inches; light gray (2.5Y 7/2) sandy Management loam, grayish brown (2.5Y 5/2) moist; weak medium subangular blocky structure; slightly For management information about this map unit, hard, friable, nonsticky, nonplastic; few very fine see appropriate sections in Part II of this publication. roots; common fine masses of lime; strongly effervescent; moderately alkaline; clear smooth Assinniboine Series boundary. BC—42 to 60 inches; light brownish gray (2.5Y 6/2) Depth class: Very deep (more than 60 inches) sandy loam, grayish brown (2.5Y 5/2) moist; Drainage class: Well drained massive; loose, friable, nonsticky, nonplastic; Permeability: Moderate (0.6 to 2.0 inches/hour) slightly effervescent; moderately alkaline. Landform: Alluvial fans, stream terraces, sedimentary plains, and hills Range in Characteristics Parent material: Alluvium Slope range: 0 to 15 percent Soil temperature: 43 to 47 degrees F Annual precipitation: 12 to 15 inches Thickness of the mollic epipedon: 7 to 16 inches Depth to the Btk horizon: 10 to 25 inches Taxonomic Class: Fine-loamy, mixed Aridic Other features: In areas that are cultivated, a sandy Argiborolls clay loam texture results from mixing the A and Bt horizons. Some pedons have a thin strata of Typical Pedon loamy sand, loamy fine sand, or sand at depths Assinniboine sandy clay loam, 2 to 8 percent below 40 inches. slopes, in an area of rangeland, 2,050 feet south and A horizon 2,130 feet west of the northeast corner of sec. 21, Hue: 10YR or 2.5Y T. 2 N., R. 57 E. Chroma: 2 or 3 A—0 to 3 inches; grayish brown (10YR 5/3) fine Texture: Fine sandy loam or sandy clay loam sandy loam, dark brown (10YR 3/3) moist; weak when mixed to 7 inches Carter County, Montana—Part I 37

Content of rock fragments: 0 to 15 percent Major Component Description pebbles Surface layer texture: Sandy clay loam Clay content: 5 to 25 percent Depth class: Very deep (more than 60 inches) Reaction: pH 6.1 to 7.8 Drainage class: Well drained Bt horizons Dominant parent material: Alluvium Hue: 10YR or 2.5Y Native plant cover type: Rangeland Value: 4, 5, or 6 dry; 3, 4, or 5 moist Flooding: None Chroma: 2 to 4 Available water capacity: Mainly 8.6 inches Texture: Sandy clay loam or fine sandy loam Clay content: 18 to 30 percent A typical soil description with range in Content of rock fragments: 0 to 15 percent characteristics is included, in alphabetical order, pebbles in this section. Reaction: pH 6.6 to 7.8 Management Btk and Bk horizons Hue: 2.5Y or 10YR For management information about this map unit, Value: 5, 6, 7, or 8 dry; 4, 5, or 6 moist see appropriate sections in Part II of this publication. Chroma: 2 to 4 Texture: Sandy loam, fine sandy loam, or sandy clay loam 74C—Assinniboine sandy clay loam, Clay content: 10 to 27 percent 2 to 8 percent slopes Content of rock fragments: 0 to 15 percent pebbles Calcium carbonate equivalent: 5 to 15 percent Setting Reaction: pH 7.4 to 8.4 Landform: Alluvial fans and stream terraces BC horizon Slope: 2 to 8 percent Hue: 2.5Y or 10YR Mean annual precipitation: 12 to 15 inches Value: 5, 6, or 7 dry; 4 or 5 moist Composition Chroma: 2 to 4 Texture: Stratifications of fine sandy loam, sandy Major Components loam, loamy fine sand, and fine sand Assinniboine and similar soils: 85 percent Clay content: 10 to 27 percent Minor Components Content of rock fragments: 0 to 15 percent Archin and similar soils: 0 to 4 percent pebbles Eapa and similar soils: 0 to 4 percent Reaction: pH 7.4 to 8.4 Chinook and similar soils: 0 to 4 percent Marmarth and similar soils: 0 to 3 percent 74A—Assinniboine sandy clay loam, Major Component Description 0 to 2 percent slopes Surface layer texture: Sandy clay loam Depth class: Very deep (more than 60 inches) Setting Drainage class: Well drained Landform: Alluvial fans and stream terraces Dominant parent material: Alluvium Slope: 0 to 2 percent Native plant cover type: Rangeland Mean annual precipitation: 12 to 15 inches Flooding: None Available water capacity: Mainly 8.6 inches Composition Major Components A typical soil description with range in Assinniboine and similar soils: 85 percent characteristics is included, in alphabetical order, in this section. Minor Components Archin and similar soils: 0 to 4 percent Management Eapa and similar soils: 0 to 4 percent Chinook and similar soils: 0 to 4 percent For management information about this map unit, Marmarth and similar soils: 0 to 3 percent see appropriate sections in Part II of this publication. 38 Soil Survey

174C—Assinniboine-Ynot complex, 13F—Badland 2 to 8 percent slopes Setting Setting Landform: Hills Landform: Slope: 8 to 70 percent • Assinniboine—Alluvial fans and stream terraces Mean annual precipitation: 12 to 15 inches • Ynot—Alluvial fans and stream terraces Composition Slope: • Assinniboine—2 to 8 percent Major Components • Ynot—2 to 8 percent Badland: 85 percent Mean annual precipitation: 12 to 15 inches Minor Components Composition Cabbart and similar soils: 0 to 3 percent Neldore and similar soils: 0 to 3 percent Major Components Yawdim and similar soils: 0 to 3 percent Assinniboine and similar soils: 50 percent Very shallow clayey soils: 0 to 2 percent Ynot and similar soils: 35 percent Very shallow loamy soils: 0 to 2 percent Minor Components Weingart and similar soils: 0 to 2 percent Marmarth and similar soils: 0 to 4 percent Major Component Description Twilight and similar soils: 0 to 4 percent Soils that have slopes more than 8 percent: 0 to Definition: Badlands are barren or nearly barren of 4 percent vegetation and have numerous deeply Soils with lighter colored surface layers: 0 to entrenched, intermittent drainageways. They 2 percent were formed by active geologic erosion of soft, Areas of blowouts: 0 to 1 percent multicolored sedimentary beds that are mainly sandstone, siltstone, and shale. Major Component Description Surface layer texture: Unweathered bedrock Assinniboine Flooding: None Surface layer texture: Sandy clay loam Depth class: Very deep (more than 60 inches) Drainage class: Well drained Bascovy Series Dominant parent material: Alluvium Depth class: Moderately deep (20 to 40 inches) Native plant cover type: Rangeland Drainage class: Well drained Flooding: None Permeability: Very slow (less than 0.06 inch/hour) Available water capacity: Mainly 8.6 inches Landform: Sedimentary plains and hills Parent material: Semiconsolidated shale Ynot Slope range: 0 to 21 percent Surface layer texture: Sandy loam Annual precipitation: 12 to 15 inches Depth class: Very deep (more than 60 inches) Drainage class: Well drained Taxonomic Class: Fine, montmorillonitic, frigid Dominant parent material: Alluvium Leptic Udic Haplusterts Native plant cover type: Rangeland Flooding: None Typical Pedon Available water capacity: Mainly 7.7 inches Bascovy clay, in an area of Neldore-Bascovy clays, 4 to 15 percent slopes, in an area of rangeland, A typical soil description with range in 1,500 feet north and 800 feet west of the southeast characteristics is included, in alphabetical order, corner of sec. 22, T. 3 S., R. 58 E. in this section. A—0 to 3 inches; grayish brown (2.5Y 5/2) clay, dark Management grayish brown (2.5Y 4/2) moist; weak medium For management information about this map unit, subangular blocky structure parting to moderate see appropriate sections in Part II of this publication. fine granular; slightly hard, friable, moderately Carter County, Montana—Part I 39

sticky, moderately plastic; few fine and many very Electrical conductivity: 2 to 4 mmhos/cm fine roots; few very fine pores; neutral; clear Reaction: pH 6.1 to 8.4 smooth boundary. Bssy horizon Bss—3 to 12 inches; pale brown (10YR 6/3) clay, Hue: 10YR, 2.5Y, or 5Y brown (10YR 5/3) moist; moderate medium Value: 5 or 6 dry; 4 or 5 moist prismatic structure parting to moderate medium Chroma: 1 to 3 and coarse subangular blocky; hard, firm, very Texture: Clay or silty clay sticky, very plastic; few fine and many very fine Clay content: 40 to 60 percent roots; common very fine pores; common distinct Gypsum content: 1 to 5 percent slickensides; neutral; clear smooth boundary. Electrical conductivity: 2 to 4 mmhos/cm Bssy—12 to 19 inches; pale brown (10YR 6/3) clay, Reaction: pH 6.1 to 8.4 brown (10YR 5/3) moist; weak medium and coarse subangular blocky structure; very hard, BC and C horizons firm, very sticky, very plastic; few very fine roots; Hue: 10YR, 2.5Y, or 5Y common very fine pores; common distinct Value: 5 or 6 dry; 4 or 5 moist slickensides; many very fine and fine masses and Chroma: 1 or 2 seams of gypsum crystals; disseminated lime; Texture: Clay or silty clay slightly effervescent; slightly alkaline; clear Clay content: 40 to 60 percent smooth boundary. Electrical conductivity: 2 to 8 mmhos/cm BC—19 to 26 inches; grayish brown (2.5Y 5/2) clay, Reaction: pH 5.1 to 8.4 dark grayish brown (2.5Y 4/2) moist; massive; hard, firm, moderately sticky, moderately plastic; few very fine roots; slightly alkaline; gradual 90C—Bascovy clay, 2 to 8 percent slopes smooth boundary. C—26 to 34 inches; grayish brown (2.5Y 5/2) clay, Setting dark grayish brown (2.5Y 4/2) moist; massive; Landform: Sedimentary plains hard, firm, moderately sticky, moderately plastic; Slope: 2 to 8 percent slightly acid; abrupt smooth boundary. Mean annual precipitation: 12 to 15 inches Cr—34 to 60 inches; grayish brown (2.5Y 5/2) semiconsolidated shale that crushes to clay, dark Composition grayish brown (2.5Y 4/2) moist. Major Components Range in Characteristics Bascovy and similar soils: 85 percent Soil temperature: 42 to 47 degrees F Minor Components Depth to the Cr horizon: 20 to 40 inches Neldore and similar soils: 0 to 3 percent Soil phases: Warm Marvan and similar soils: 0 to 3 percent Taxonomic note: Map units 623D, 633D, and 635C Weingart and similar soils: 0 to 3 percent are taxadjuncts to the Bascovy series in order to Soils with silt loam surface layers: 0 to 3 percent join soils that have an average soil temperature Soils with calcareous surface layers: 0 to 3 percent greater than 47 degrees F. Major Component Description A horizon Surface layer texture: Clay Hue: 10YR, 2.5Y, or 5Y Depth class: Moderately deep (20 to 40 inches) Value: 5, 6, or 7 dry; 3, 4, or 5 moist Drainage class: Well drained Chroma: 1 to 3 Dominant parent material: Semiconsolidated shale Clay content: 40 to 60 percent residuum Electrical conductivity: 2 to 4 mmhos/cm Native plant cover type: Rangeland Reaction: pH 6.6 to 8.4 Flooding: None Bss horizon Sodium affected: Sodic within 30 inches Hue: 10YR, 2.5Y, or 5Y Available water capacity: Mainly 5.3 inches Value: 5, 6, or 7 dry; 4 or 5 moist Chroma: 1 to 3 A typical soil description with range in Texture: Clay or silty clay characteristics is included, in alphabetical order, Clay content: 40 to 60 percent in this section. 40 Soil Survey

Management Slope: • Bascovy—2 to 8 percent For management information about this map unit, • Ethridge—2 to 8 percent see appropriate sections in Part II of this publication. Mean annual precipitation: 12 to 15 inches Composition 90D—Bascovy clay, Major Components 8 to 15 percent slopes Bascovy and similar soils: 50 percent Ethridge and similar soils: 35 percent Minor Components Setting Neldore and similar soils: 0 to 4 percent Landform: Hills Eapa and similar soils: 0 to 4 percent Slope: 8 to 15 percent Weingart and similar soils: 0 to 3 percent Mean annual precipitation: 12 to 15 inches Marvan and similar soils: 0 to 3 percent Abor and similar soils: 0 to 1 percent Composition Major Component Description Major Components Bascovy and similar soils: 85 percent Bascovy Surface layer texture: Clay Minor Components Depth class: Moderately deep (20 to 40 inches) Neldore and similar soils: 0 to 4 percent Drainage class: Well drained Marvan and similar soils: 0 to 4 percent Dominant parent material: Semiconsolidated shale Weingart and similar soils: 0 to 4 percent residuum Soils with silt loam surface layers: 0 to 2 percent Native plant cover type: Rangeland Soils with calcareous surface layers: 0 to 1 percent Flooding: None Major Component Description Sodium affected: Sodic within 30 inches Available water capacity: Mainly 5.3 inches Surface layer texture: Clay Depth class: Moderately deep (20 to 40 inches) Ethridge Drainage class: Well drained Surface layer texture: Silty clay loam Dominant parent material: Semiconsolidated shale Depth class: Very deep (more than 60 inches) residuum Drainage class: Well drained Native plant cover type: Rangeland Dominant parent material: Alluvium Flooding: None Native plant cover type: Rangeland Sodium affected: Sodic within 30 inches Flooding: None Available water capacity: Mainly 5.3 inches Available water capacity: Mainly 9.9 inches A typical soil description with range in A typical soil description with range in characteristics is included, in alphabetical order, characteristics is included, in alphabetical order, in this section. in this section. 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.

490C—Bascovy-Ethridge complex, 590C—Bascovy-Marvan complex, 2 to 8 percent slopes 2 to 8 percent slopes

Setting Setting Landform: Landform: • Bascovy—Sedimentary plains • Bascovy—Sedimentary plains • Ethridge—Stream terraces • Marvan—Sedimentary plains Carter County, Montana—Part I 41

Slope: Composition • Bascovy—2 to 8 percent Major Components • Marvan—2 to 8 percent Bascovy and similar soils: 85 percent Mean annual precipitation: 12 to 15 inches Minor Components Composition Neldore and similar soils: 0 to 4 percent Major Components Soils with calcareous surface layers: 0 to 4 percent Bascovy and similar soils: 50 percent Marvan and similar soils: 0 to 4 percent Marvan and similar soils: 35 percent Weingart and similar soils: 0 to 2 percent Soils with silty clay loam surfaces: 0 to 1 percent Minor Components Neldore and similar soils: 0 to 4 percent Major Component Description Kobase and similar soils: 0 to 4 percent Surface layer texture: Clay Weingart and similar soils: 0 to 4 percent Depth class: Moderately deep (20 to 40 inches) Abor and similar soils: 0 to 3 percent Drainage class: Well drained Major Component Description Dominant parent material: Semiconsolidated shale residuum Bascovy Native plant cover type: Rangeland Surface layer texture: Clay Flooding: None Depth class: Moderately deep (20 to 40 inches) Sodium affected: Sodic within 30 inches Drainage class: Well drained Available water capacity: Mainly 5.3 inches Dominant parent material: Semiconsolidated shale residuum A typical soil description with range in Native plant cover type: Rangeland characteristics is included, in alphabetical order, Flooding: None in this section. Sodium affected: Sodic within 30 inches Available water capacity: Mainly 5.3 inches Management

Marvan For management information about this map unit, Surface layer texture: Silty clay see appropriate sections in Part II of this publication. Depth class: Very deep (more than 60 inches) Drainage class: Well drained Dominant parent material: Alluvium 633D—Bascovy-Neldore clays, warm, Native plant cover type: Rangeland 6 to 21 percent slopes Flooding: None Available water capacity: Mainly 6.9 inches Setting Landform: A typical soil description with range in • Bascovy—Sedimentary plains and hills characteristics is included, in alphabetical order, • Neldore—Sedimentary plains and hills in this section. Position on landform: Management • Bascovy—Backslopes and shoulders • Neldore—Shoulders and summits For management information about this map unit, Slope: see appropriate sections in Part II of this publication. • Bascovy—6 to 21 percent • Neldore—6 to 21 percent Mean annual precipitation: 12 to 15 inches 623D—Bascovy clay, warm, Composition 0 to 9 percent slopes Major Components Bascovy and similar soils: 50 percent Setting Neldore and similar soils: 35 percent Landform: Sedimentary plains and hills Minor Components Slope: 0 to 9 percent Abor and similar soils: 0 to 4 percent Mean annual precipitation: 12 to 15 inches Weingart and similar soils: 0 to 4 percent 42 Soil Survey

Volborg and similar soils: 0 to 4 percent thick platy structure parting to moderate fine Vaeda and similar soils: 0 to 3 percent subangular blocky; slightly hard, friable, slightly sticky, slightly plastic; common very fine and fine Major Component Description roots; few very fine and fine pores; slightly acid; Bascovy clear smooth boundary. Surface layer texture: Clay Bt1—7 to 15 inches; brown (10YR 5/3) loam, dark Depth class: Moderately deep (20 to 40 inches) brown (10YR 3/3) moist; moderate medium and Drainage class: Well drained coarse subangular blocky structure; hard, friable, Dominant parent material: Semiconsolidated shale slightly sticky, slightly plastic; common very fine residuum and fine roots; common very fine tubular pores; Native plant cover type: Rangeland common faint clay films on faces of peds and in Flooding: None pores; slightly acid; clear wavy boundary. Sodium affected: Sodic within 30 inches Bt2—15 to 30 inches; brown (10YR 5/3) clay loam, Available water capacity: Mainly 5.3 inches brown (10YR 4/3) moist; strong fine and medium subangular blocky structure; very hard, firm, Neldore moderately sticky, moderately plastic; few fine Surface layer texture: Clay and common very fine roots; common very fine Depth class: Shallow (10 to 20 inches) and fine tubular pores; common faint clay films on Drainage class: Well drained faces of peds and in pores; neutral; gradual wavy Dominant parent material: Semiconsolidated shale boundary. residuum BC—30 to 34 inches; pale brown (10YR 6/3) sandy Native plant cover type: Rangeland clay loam, brown (10YR 5/3) moist; moderate Flooding: None medium subangular blocky structure parting to Available water capacity: Mainly 1.8 inches moderate fine subangular blocky; very hard, friable, slightly sticky, slightly plastic; few very fine A typical soil description with range in roots; few very fine pores; neutral; abrupt wavy characteristics is included, in alphabetical order, boundary. in this section. 2C—34 to 60 inches; variegated colored sand; single grain; loose, nonsticky, nonplastic; 10 percent Management pebbles; neutral. For management information about this map unit, see appropriate sections in Part II of this publication. Range in Characteristics Soil temperature: 42 to 47 degrees F Beaverflat Series Thickness of the mollic epipedon: 10 to 16 inches Depth to the 2C horizon: 20 to 40 inches Depth class: Very deep (more than 60 inches) Ap horizon Drainage class: Well drained Hue: 10YR or 2.5Y Permeability: Moderate (0.6 to 2.0 inches/hour) over Value: 4 or 5 dry; 2 or 3 moist rapid (6.0 to 20.0 inches/hour) Chroma: 2 or 3 Landform: Relict stream terraces Texture: Loam or sandy loam Parent material: Alluvium Clay content: 10 to 27 percent Slope range: 0 to 4 percent Content of rock fragments: 0 to 15 percent Annual precipitation: 12 to 15 inches pebbles Reaction: pH 5.6 to 6.5 Taxonomic Class: Fine-loamy over sandy or sandy- skeletal mixed Aridic Argiborolls Bt horizons Hue: 10YR or 2.5Y Typical Pedon Value: 4, 5, or 6 dry; 3 or 4 moist Beaverflat loam, 0 to 4 percent slopes, in an area of Chroma: 2 to 4 cropland, 1,300 feet south and 50 feet west of the Texture: Loam, clay loam, or sandy clay loam northeast corner of sec. 27, T. 2 N., R. 56 E. Clay content: 20 to 35 percent Content of rock fragments: 0 to 15 percent Ap—0 to 7 inches; grayish brown (10YR 5/2) loam, pebbles very dark grayish brown (10YR 3/2) moist; weak Reaction: pH 6.1 to 7.3 Carter County, Montana—Part I 43

BC horizon Management Hue: 10YR or 2.5Y For management information about this map unit, Value: 5 or 6 dry; 4 or 5 moist see appropriate sections in Part II of this publication. Chroma: 3 or 4 Texture: Loam or sandy clay loam Clay content: 15 to 27 percent 130A—Beaverflat sandy loam, Content of rock fragments: 0 to 15 percent 0 to 4 percent slopes pebbles Reaction: pH 6.6 to 7.3 Setting 2C horizon Landform: Relict stream terraces Hue: 10YR or 2.5Y Slope: 0 to 4 percent Value: 6 or 7 dry; 5 or 6 moist Mean annual precipitation: 12 to 15 inches Chroma: 3 or 4 Texture: Sand or loamy sand Composition Clay content: 0 to 5 percent Major Components Content of rock fragments: 0 to 35 percent Beaverflat and similar soils: 85 percent pebbles Reaction: pH 6.6 to 7.3 Minor Components Varney and similar soils: 0 to 4 percent Eapa and similar soils: 0 to 4 percent 30A—Beaverflat loam, Soils with calcareous surface layers: 0 to 4 percent 0 to 4 percent slopes Soils with darker colored surface layers: 0 to 2 percent Soils with lighter colored surface layers: 0 to Setting 1 percent Landform: Relict stream terraces Major Component Description Slope: 0 to 4 percent Mean annual precipitation: 12 to 15 inches Surface layer texture: Sandy loam Depth class: Very deep (more than 60 inches) Composition Drainage class: Well drained Major Components Dominant parent material: Alluvium Beaverflat and similar soils: 85 percent Native plant cover type: Rangeland Flooding: None Minor Components Available water capacity: Mainly 6.6 inches Varney and similar soils: 0 to 4 percent Eapa and similar soils: 0 to 4 percent A typical soil description with range in Soils with darker colored surface layers: 0 to characteristics is included, in alphabetical order, 4 percent in this section. Soils with lighter colored surface layers: 0 to 3 percent Management Major Component Description For management information about this map unit, see appropriate sections in Part II of this publication. Surface layer texture: Loam Depth class: Very deep (more than 60 inches) Drainage class: Well drained Beenom Series Dominant parent material: Alluvium Native plant cover type: Rangeland Depth class: Shallow (10 to 20 inches) Flooding: None Drainage class: Well drained Available water capacity: Mainly 6.7 inches Permeability: Moderate (0.6 to 2.0 inches/hour) Landform: Bedrock-floored plains A typical soil description with range in Parent material: Sandstone and quartzite residuum characteristics is included, in alphabetical order, Slope range: 1 to 8 percent in this section. Annual precipitation: 15 to 17 inches 44 Soil Survey

Taxonomic Class: Loamy, mixed Lithic Argiborolls Texture: Clay loam, fine sandy loam, or sandy clay loam Typical Pedon Clay content: 18 to 35 percent Beenom loam, in an area of Beenom-Parchin Content of rock fragments: 0 to 30 percent complex, 2 to 8 percent slopes, in an area of pebbles rangeland, 1,200 feet north and 500 feet west of Reaction: pH 7.4 to 8.4 the southeast corner of sec. 10, T. 1 S., R. 61 E. Bt2 horizon A—0 to 4 inches; grayish brown (10YR 5/2) loam, Hue: 7.5YR, 10YR, or 2.5Y very dark grayish brown (10YR 3/2) moist; weak Value: 4 to 6 dry; 3 or 4 moist fine granular structure; soft, very friable, slightly Chroma: 2 or 3 sticky, nonplastic; many very fine roots; neutral; Texture: Clay loam, fine sandy loam, or sandy clear smooth boundary. clay loam Bt1—4 to 10 inches; brown (10YR 5/3) clay loam, Clay content: 18 to 35 percent dark brown (10YR 3/3) moist; moderate medium Content of rock fragments: 0 to 30 percent and coarse prismatic structure parting to pebbles moderate fine and medium subangular blocky; Reaction: pH 7.4 to 8.4 slightly hard, firm, moderately sticky, moderately plastic; common very fine and fine roots; many faint clay films on faces of peds, continuous 49A—Beenom-Reeder loams, distinct clay films in pores; slightly alkaline; clear 1 to 4 percent slopes smooth boundary. Bt2—10 to 16 inches; pale brown (10YR 6/3) gravelly Setting sandy clay loam, dark brown (10YR 4/3) moist; Landform: weak medium subangular blocky structure; soft, • Beenom—Bedrock-floored plains friable, slightly sticky, plastic; common very fine • Reeder—Sedimentary plains and fine roots; few very fine pores; many faint Slope: clay films on faces of peds and sandstone • Beenom—1 to 4 percent fragments, many distinct clay films in pores; 30 • Reeder—1 to 4 percent percent sandstone fragments; slightly alkaline; Mean annual precipitation: 15 to 17 inches abrupt smooth boundary. R—16 to 60 inches; hard platy sandstone. Composition Range in Characteristics Major Components Beenom and similar soils: 60 percent Soil temperature: 41 to 47 degrees F Reeder and similar soils: 25 percent Thickness of the mollic epipedon: 8 to 13 inches Depth to bedrock: 10 to 20 inches Minor Components Other features: Some pedons have a Btk horizon. Very deep loamy soils: 0 to 5 percent Taxonomic note: Map unit 49A is a taxadjunct to the Soils with slopes more than 4 percent: 0 to 5 percent Beenom series because of fragmental material to Deep soils over hard sandstone: 0 to 5 percent 30 inches. Major Component Description A horizon Beenom Hue: 7.5YR, 10YR, or 2.5Y Surface layer texture: Loam Value: 3, 4, or 5 dry; 2 or 3 moist Depth class: Shallow (10 to 20 inches) Chroma: 2 or 3 Drainage class: Well drained Clay content: 10 to 27 percent Dominant parent material: Quartzite residuum Content of rock fragments: 0 to 15 percent Native plant cover type: Rangeland pebbles Flooding: None Reaction: pH 6.6 to 7.8 Available water capacity: Mainly 4.2 inches Bt1 horizon Hue: 7.5YR, 10YR, or 2.5Y Reeder Value: 3, 4, or 5 dry; 2, 3, or 4 moist Surface layer texture: Loam Chroma: 2 or 3 Depth class: Moderately deep (20 to 40 inches) Carter County, Montana—Part I 45

Drainage class: Well drained Dominant parent material: Semiconsolidated, loamy Dominant parent material: Semiconsolidated, loamy sedimentary beds sedimentary beds Native plant cover type: Rangeland Native plant cover type: Rangeland Flooding: None Flooding: None Sodium affected: Sodic within 30 inches Available water capacity: Mainly 5.2 inches Available water capacity: Mainly 4.0 inches

A typical soil description with range in A typical soil description with range in characteristics is included, in alphabetical order, characteristics is included, in alphabetical order, in this section. in this section. 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.

116C—Beenom-Parchin complex, Belltower Series 2 to 8 percent slopes Depth class: Moderately deep (20 to 40 inches) Drainage class: Well drained Setting Permeability: Moderate (0.6 to 2.0 inches/hour) Landform: Landform: Sedimentary plains and hills • Beenom—Bedrock-floored plains Parent material: Semiconsolidated, loamy • Parchin—Sedimentary plains sedimentary beds Slope: Slope range: 4 to 60 percent • Beenom—2 to 8 percent Annual precipitation: 15 to 17 inches • Parchin—2 to 8 percent Mean annual precipitation: 15 to 17 inches Taxonomic Class: Fine-loamy, mixed Mollic Eutroboralfs Composition Typical Pedon Major Components Beenom and similar soils: 50 percent Belltower loam, in an area of Belltower-Dast complex, Parchin and similar soils: 35 percent 35 to 60 percent slopes, in an area of forestland, 1,300 feet north and 2,600 feet east of the southwest Minor Components corner of sec. 24, T. 1 N., R. 57 E. Areas of rock outcrop: 0 to 4 percent Very shallow soils: 0 to 4 percent Oi—2 inches to 0; partially decomposed forest litter. Moderately deep loamy soils: 0 to 3 percent A—0 to 8 inches; dark grayish brown (10YR 4/2) Very deep sandy loam soils: 0 to 2 percent loam, very dark grayish brown (10YR 2/2) moist; Soils with flaggy sandy loam surfaces: 0 to 2 percent weak fine subangular blocky structure parting to weak fine granular; soft, very friable, nonsticky, Major Component Description nonplastic; common medium and coarse and Beenom many very fine and fine roots; common fine and Surface layer texture: Loam many very fine tubular pores; slightly acid; clear Depth class: Shallow (10 to 20 inches) smooth boundary. Drainage class: Well drained E—8 to 17 inches; light brownish gray (2.5Y 6/2) fine Dominant parent material: Sandstone residuum sandy loam, dark grayish brown (2.5Y 4/2) moist; Native plant cover type: Rangeland moderate medium subangular blocky structure; Flooding: None soft, very friable, nonsticky, nonplastic; common Available water capacity: Mainly 2.6 inches very fine, fine, medium, and coarse roots; many very fine and fine tubular pores; 5 percent soft Parchin channers; neutral; clear wavy boundary. Surface layer texture: Fine sandy loam Bt—17 to 32 inches; light brownish gray (2.5Y 6/2) Depth class: Moderately deep (20 to 40 inches) sandy clay loam, grayish brown (2.5Y 5/2) moist; Drainage class: Well drained moderate medium prismatic structure parting to 46 Soil Survey

strong medium subangular blocky; very hard, Content of rock fragments: 10 to 60 percent—0 to firm, moderately sticky, moderately plastic; few 5 percent hard flagstones; 0 to 5 percent hard fine and medium and common very fine roots; channers; 10 to 50 percent soft flagstones and common fine and many very fine tubular pores; channers 20 percent soft channers; common faint clay films Reaction: pH 6.1 to 7.3 on faces of peds, common distinct clay films in Bk horizon pores; neutral; clear wavy boundary. Hue: 2.5Y or 5Y Bk—32 to 36 inches; light gray (2.5Y 7/2) loam, light Value: 5, 6, or 7 dry brownish gray (2.5Y 6/2) moist; moderate Chroma: 2 to 4 medium prismatic structure; soft, very friable, Texture: Loam, clay loam, sandy clay loam, or slightly sticky, slightly plastic; few very fine fine sandy loam and fine roots; many very fine tubular pores; Clay content: 15 to 30 percent 50 percent soft channers and flagstones; few Content of rock fragments: 20 to 80 percent—0 to fine and medium masses and seams of lime; 5 percent hard flagstones; 0 to 5 percent hard strongly effervescent; moderately alkaline; channers; 20 to 70 percent soft flagstones and gradual wavy boundary. channers Cr—36 to 60 inches; light gray (5Y 7/2) Calcium carbonate equivalent: 5 to 15 percent semiconsolidated loamy sedimentary beds that Reaction: pH 7.4 to 8.4 crush to a loam, olive gray (5Y 5/2) moist. Range in Characteristics 144D—Belltower-Reeder-Vebar complex, Soil temperature: 42 to 47 degrees F 4 to 15 percent slopes Depth to the Bt horizon: 10 to 18 inches Depth to the Bk horizon: 19 to 35 inches Setting Depth to the Cr horizon: 20 to 40 inches Landform: A horizon • Belltower—Sedimentary plains and hills Value: 3, 4, or 5 dry; 2 or 3 moist • Reeder—Sedimentary plains and hills Chroma: 1 or 2 • Vebar—Sedimentary plains and hills Clay content: 12 to 20 percent Slope: Content of rock fragments: 0 to 30 percent—0 to • Belltower—4 to 15 percent 5 percent hard flagstones; 0 to 5 percent hard • Reeder—4 to 15 percent channers; 0 to 20 percent soft flagstones and • Vebar—4 to 15 percent channers Mean annual precipitation: 15 to 17 inches Reaction: pH 6.1 to 7.3 Composition E horizon Hue: 10YR or 2.5Y Major Components Value: 5 or 6 dry; 4 or 5 moist Belltower and similar soils: 30 percent Chroma: 2 or 3 Reeder and similar soils: 30 percent Texture: Loam, sandy loam, or fine sandy loam Vebar and similar soils: 25 percent Clay content: 12 to 18 percent Minor Components Content of rock fragments: 0 to 30 percent—0 to Very shallow loamy soils: 0 to 4 percent 5 percent hard flagstones; 0 to 5 percent hard Shallow loamy soils: 0 to 4 percent channers; 0 to 20 percent soft flagstones and Very deep sandy soils: 0 to 3 percent channers Soils with flaggy and channery surfaces: 0 to Reaction: pH 6.1 to 7.3 2 percent Bt horizon Soils with flagstones: 0 to 2 percent Hue: 10YR, 2.5Y, or 5Y Major Component Description Value: 5 or 6 dry; 4 or 5 moist Chroma: 2 to 4 Belltower Texture: Loam, sandy clay loam, or clay loam Surface layer texture: Loam Clay content: 20 to 35 percent Depth class: Moderately deep (20 to 40 inches) Carter County, Montana—Part I 47

Drainage class: Well drained Composition Dominant parent material: Semiconsolidated, loamy Major Components sedimentary beds Belltower and similar soils: 30 percent Native plant cover type: Forestland Dast and similar soils: 30 percent Flooding: None Reeder and similar soils: 25 percent Available water capacity: Mainly 5.1 inches Minor Components Reeder Shallow sandy soils: 0 to 4 percent Surface layer texture: Loam Shallow loamy soils: 0 to 4 percent Depth class: Moderately deep (20 to 40 inches) Areas of rock outcrop: 0 to 4 percent Drainage class: Well drained Very deep sandy soils: 0 to 3 percent Dominant parent material: Semiconsolidated, loamy Major Component Description sedimentary beds Native plant cover type: Forestland Belltower Flooding: None Surface layer texture: Loam Available water capacity: Mainly 5.2 inches Depth class: Moderately deep (20 to 40 inches) Drainage class: Well drained Vebar Dominant parent material: Semiconsolidated, loamy Surface layer texture: Fine sandy loam sedimentary beds Depth class: Moderately deep (20 to 40 inches) Native plant cover type: Forestland Drainage class: Well drained Flooding: None Dominant parent material: Semiconsolidated, sandy Available water capacity: Mainly 5.1 inches sedimentary beds Native plant cover type: Forestland Dast Flooding: None Surface layer texture: Sandy loam Available water capacity: Mainly 3.4 inches Depth class: Moderately deep (20 to 40 inches) Drainage class: Well drained A typical soil description with range in Dominant parent material: Semiconsolidated, sandy characteristics is included, in alphabetical order, sedimentary beds in this section. Native plant cover type: Forestland Flooding: None Management Available water capacity: Mainly 3.6 inches For management information about this map unit, Reeder see appropriate sections in Part II of this publication. Surface layer texture: Loam Depth class: Moderately deep (20 to 40 inches) Drainage class: Well drained 144E—Belltower-Dast-Reeder complex, Dominant parent material: Semiconsolidated, loamy 15 to 35 percent slopes sedimentary beds Native plant cover type: Forestland Setting Flooding: None Available water capacity: Mainly 5.2 inches Landform: • Belltower—Hills A typical soil description with range in • Dast—Hills characteristics is included, in alphabetical order, • Reeder—Hills in this section. Slope: • Belltower—15 to 35 percent Management • Dast—15 to 35 percent • Reeder—15 to 35 percent For management information about this map unit, Mean annual precipitation: 15 to 17 inches see appropriate sections in Part II of this publication. 48 Soil Survey

144F—Belltower-Dast complex, Bickerdyke Series 35 to 60 percent slopes Depth class: Very deep (more than 60 inches) Drainage class: Well drained Setting Permeability: Slow (0.06 to 0.2 inch/hour) Landform: Landform: Sedimentary plains • Belltower—Hills Parent material: Alluvium • Dast—Hills Slope range: 0 to 8 percent Slope: Annual precipitation: 12 to 15 inches • Belltower—35 to 60 percent • Dast—35 to 60 percent Taxonomic Class: Fine, montmorillonitic, frigid Sodic Mean annual precipitation: 15 to 17 inches Haplusterts Typical Pedon Composition Bickerdyke clay, 0 to 2 percent slopes, in an area of Major Components rangeland, 2,200 feet north and 1,800 feet west of the Belltower and similar soils: 45 percent southeast corner of sec. 27, T. 5 S., R. 61 E. Dast and similar soils: 40 percent E—0 to 1 inch; light brownish gray (2.5Y 6/2) clay, Minor Components grayish brown (2.5Y 5/2) moist; massive crust; Shallow sandy soils: 0 to 4 percent hard, friable, very sticky, very plastic; many very Shallow loamy soils: 0 to 4 percent fine roots; many very fine pores; moderately Soils that have slopes less than 35 percent: 0 to alkaline; abrupt smooth boundary. 4 percent Bss—1 to 8 inches; grayish brown (2.5Y 5/2) clay, Moderately deep loamy soils: 0 to 3 percent dark grayish brown (2.5Y 4/2) moist; moderate medium subangular blocky structure; very hard, Major Component Description very firm, very sticky, very plastic; many very fine roots; few fine and many very fine pores; few faint Belltower slickensides; moderately alkaline; clear smooth Surface layer texture: Loam boundary. Depth class: Moderately deep (20 to 40 inches) Bssy—8 to 14 inches; light brownish gray (2.5Y 6/2) Drainage class: Well drained clay, grayish brown (2.5Y 5/2) moist; moderate Dominant parent material: Semiconsolidated, loamy medium subangular blocky structure; very hard, sedimentary beds very firm, very sticky, very plastic; few very fine Native plant cover type: Forestland roots; common very fine pores; common Flooding: None intersecting slickensides; common fine nests and Available water capacity: Mainly 5.1 inches seams of gypsum crystals; moderately alkaline; clear smooth boundary. Dast Bssyz—14 to 22 inches; light brownish gray (2.5Y Surface layer texture: Sandy loam 6/2) clay, grayish brown (2.5Y 5/2) moist; Depth class: Moderately deep (20 to 40 inches) moderate medium subangular blocky structure; Drainage class: Well drained very hard, very firm, very sticky, very plastic; few Dominant parent material: Semiconsolidated, sandy very fine roots; common very fine pores; common sedimentary beds intersecting slickensides; common fine nests and Native plant cover type: Forestland seams of gypsum crystals; few fine seams and Flooding: None nests of other salts; strongly alkaline; gradual Available water capacity: Mainly 3.6 inches smooth boundary. Byz—22 to 60 inches; grayish brown (2.5Y 5/2) clay, A typical soil description with range in dark grayish brown (2.5Y 4/2) moist; moderate characteristics is included, in alphabetical order, medium subangular blocky structure; very hard, in this section. very firm, very sticky, very plastic; few very fine roots; common very fine pores; common fine Management nests and seams of gypsum crystals; few fine For management information about this map unit, seams and nests of other salts; moderately see appropriate sections in Part II of this publication. alkaline. Carter County, Montana—Part I 49

Range in Characteristics 87A—Bickerdyke clay, 0 to 2 percent slopes Soil temperature: 43 to 47 degrees F Depth to the Bssy horizon: 6 to 15 inches 1 Setting Other features: This soil has /2- to 1-inch cracks that extend to 20 inches or more and have few to Landform: Sedimentary plains many slickensides. The 1 chromas are Slope: 0 to 2 percent lithochromic. Mean annual precipitation: 12 to 15 inches E horizon Composition Hue: 10YR or 2.5Y Major Components Value: 5, 6, or 7 dry; 4 or 5 moist Bickerdyke and similar soils: 85 percent Chroma: 1 or 2 Clay content: 40 to 60 percent Minor Components Electrical conductivity: 0 to 2 mmhos/cm Gerdrum and similar soils: 0 to 4 percent Reaction: pH 7.4 to 8.4 Marvan and similar soils: 0 to 4 percent Weingart and similar soils: 0 to 3 percent Bss horizon Bascovy and similar soils: 0 to 2 percent Hue: 10YR or 2.5Y Soils with silty clay loam surfaces: 0 to 2 percent Value: 5 or 6 dry; 4 or 5 moist Chroma: 1 or 2 Major Component Description Texture: Clay or silty clay Surface layer texture: Clay Clay content: 40 to 60 percent Depth class: Very deep (more than 60 inches) Electrical conductivity: 0 to 2 mmhos/cm Drainage class: Well drained Reaction: pH 7.9 to 8.4 Dominant parent material: Alluvium Bssy horizon Native plant cover type: Rangeland Hue: 10YR or 2.5Y Flooding: None Value: 4, 5, or 6 dry; 4 or 5 moist Salt affected: Saline within 30 inches Chroma: 1 or 2 Sodium affected: Sodic within 30 inches Texture: Clay or silty clay Available water capacity: Mainly 6.6 inches Clay content: 40 to 60 percent Electrical conductivity: 4 to 8 mmhos/cm A typical soil description with range in Sodium adsorption ratio: 10 to 15 characteristics is included, in alphabetical order, Gypsum content: 5 to 15 percent in this section. Reaction: pH 7.9 to 9.0 Management Bssyz horizon For management information about this map unit, Hue: 10YR or 2.5Y see appropriate sections in Part II of this publication. Value: 4, 5, or 6 dry; 4 or 5 moist Chroma: 1 or 2 Texture: Clay or silty clay 87C—Bickerdyke clay, Clay content: 40 to 60 percent 2 to 8 percent slopes Electrical conductivity: 8 to 16 mmhos/cm Sodium adsorption ratio: 15 to 30 Setting Gypsum content: 5 to 15 percent Reaction: pH 7.9 to 9.0 Landform: Sedimentary plains Slope: 2 to 8 percent Byz horizon Mean annual precipitation: 12 to 15 inches Hue: 10YR or 2.5Y Value: 4, 5, or 6 dry; 4 or 5 moist Composition Chroma: 1 or 2 Major Components Texture: Clay or silty clay Bickerdyke and similar soils: 85 percent Clay content: 40 to 60 percent Electrical conductivity: 8 to 16 mmhos/cm Minor Components Sodium adsorption ratio: 15 to 30 Gerdrum and similar soils: 0 to 4 percent Reaction: pH 7.9 to 9.4 Marvan and similar soils: 0 to 4 percent 50 Soil Survey

Weingart and similar soils: 0 to 3 percent fine subangular blocky structure; soft, very friable, Bascovy and similar soils: 0 to 2 percent nonsticky, nonplastic; many very fine and fine Soils with silty clay loam surfaces: 0 to 2 percent roots; few very fine pores; few fine masses of lime; slightly effervescent; moderately alkaline; Major Component Description gradual smooth boundary. Surface layer texture: Clay Cr—16 to 60 inches; light yellowish brown (2.5Y 6/4) Depth class: Very deep (more than 60 inches) semiconsolidated sandy sedimentary beds that Drainage class: Well drained crush to loamy sand, grayish brown (2.5Y 5/2) Dominant parent material: Alluvium moist. Native plant cover type: Rangeland Range in Characteristics Flooding: None Salt affected: Saline within 30 inches Soil temperature: 44 to 47 degrees F Sodium affected: Sodic within 30 inches Depth to the Cr horizon: 10 to 20 inches Available water capacity: Mainly 6.6 inches A horizon Hue: 2.5Y, 10YR, or 7.5YR A typical soil description with range in Value: 5, 6, or 7 dry; 4 or 5 moist characteristics is included, in alphabetical order, Chroma: 2 or 3 in this section. Clay content: 5 to 15 percent Management Reaction: pH 7.4 to 8.4 For management information about this map unit, Bk horizon see appropriate sections in Part II of this publication. Hue: 2.5Y, 10YR, or 7.5YR Value: 5, 6, or 7 dry; 4 to 6 moist Chroma: 2 to 4 Blacksheep Series Texture: Very fine sandy loam, fine sandy loam, sandy loam, or loamy fine sand Depth class: Shallow (10 to 20 inches) Clay content: 5 to 15 percent Drainage class: Well drained Calcium carbonate equivalent: 5 to 10 percent Permeability: Moderately rapid (2.0 to 6.0 inches/ Reaction: pH 7.9 to 8.4 hour) Landform: Hills and sedimentary plains Parent material: Semiconsolidated, sandy 55D—Blacksheep-Twilight fine sandy sedimentary beds loams, 8 to 15 percent slopes Slope range: 4 to 50 percent Annual precipitation: 12 to 15 inches Setting Taxonomic Class: Loamy, mixed (calcareous), frigid, Landform: shallow Aridic Ustorthents • Blacksheep—Hills • Twilight—Hills Typical Pedon Position on landform: Blacksheep fine sandy loam, in an area of • Blacksheep—Shoulders and summits Blacksheep-Twilight fine sandy loams, 8 to 15 • Twilight—Backslopes and footslopes percent slopes, in an area of rangeland, 2,100 feet Slope: south and 1,800 feet west of the northeast corner of • Blacksheep—8 to 15 percent sec. 33, T. 6 S., R. 55 E. • Twilight—8 to 15 percent Mean annual precipitation: 12 to 15 inches A—0 to 4 inches; grayish brown (2.5Y 5/2) fine sandy loam, dark grayish brown (2.5Y 4/2) moist; weak Composition fine subangular blocky structure; soft, very friable, Major Components nonsticky, nonplastic; many very fine and fine Blacksheep and similar soils: 45 percent roots; few very fine and fine pores; slightly Twilight and similar soils: 45 percent effervescent; slightly alkaline; clear wavy boundary. Minor Components Bk—4 to 16 inches; light olive brown (2.5Y 5/4) sandy Cabbart and similar soils: 0 to 2 percent loam, dark grayish brown (2.5Y 4/2) moist; weak Busby and similar soils: 0 to 2 percent Carter County, Montana—Part I 51

Very shallow loamy soils: 0 to 2 percent Composition Shallow silt loam soils: 0 to 2 percent Major Components Soils that have slopes more than 15 percent: 0 to Blacksheep and similar soils: 50 percent 1 percent Twilight and similar soils: 40 percent Areas of blowouts: 0 to 1 percent Minor Components Major Component Description Cabbart and similar soils: 0 to 2 percent Blacksheep Shallow silt loam soils: 0 to 2 percent Surface layer texture: Fine sandy loam Areas of blowouts: 0 to 2 percent Depth class: Shallow (10 to 20 inches) Areas of rock outcrop: 0 to 2 percent Drainage class: Well drained Very shallow loamy soils: 0 to 1 percent Dominant parent material: Semiconsolidated, sandy Soils that have slopes less than 15 percent: 0 to sedimentary beds 1 percent Native plant cover type: Rangeland Major Component Description Flooding: None Available water capacity: Mainly 2.3 inches Blacksheep Surface layer texture: Fine sandy loam Twilight Depth class: Shallow (10 to 20 inches) Surface layer texture: Fine sandy loam Drainage class: Well drained Depth class: Moderately deep (20 to 40 inches) Dominant parent material: Semiconsolidated, sandy Drainage class: Well drained sedimentary beds Dominant parent material: Semiconsolidated, sandy Native plant cover type: Rangeland sedimentary beds Flooding: None Native plant cover type: Rangeland Available water capacity: Mainly 2.3 inches Flooding: None Available water capacity: Mainly 4.2 inches Twilight Surface layer texture: Fine sandy loam A typical soil description with range in Depth class: Moderately deep (20 to 40 inches) characteristics is included, in alphabetical order, Drainage class: Well drained in this section. Dominant parent material: Semiconsolidated, sandy sedimentary beds Management Native plant cover type: Rangeland Flooding: None For management information about this map unit, Available water capacity: Mainly 4.2 inches see appropriate sections in Part II of this publication. A typical soil description with range in characteristics is included, in alphabetical order, 55E—Blacksheep-Twilight fine sandy in this section. loams, 15 to 45 percent slopes Management

Setting For management information about this map unit, see appropriate sections in Part II of this publication. Landform: • Blacksheep—Hills • Twilight—Hills 155E—Blacksheep-Rock outcrop Position on landform: complex, 25 to 50 percent slopes • Blacksheep—Shoulders and summits • Twilight—Backslopes and footslopes Setting Slope: • Blacksheep—15 to 45 percent Landform: • Twilight—15 to 45 percent • Blacksheep—Hills Mean annual precipitation: 12 to 15 inches • Rock outcrop—Hills 52 Soil Survey

Position on landform: Typical Pedon • Blacksheep—Backslopes Bonfri loam, 8 to 15 percent slopes, in an area of • Rock outcrop—Shoulders and summits rangeland, 500 feet north and 2,400 feet west of the Slope: 25 to 50 percent southeast corner of sec. 22, T. 3 N., R. 57 E. Mean annual precipitation: 12 to 15 inches A—0 to 4 inches; brown (10YR 5/3) loam, dark Composition grayish brown (10YR 4/2) moist; moderate coarse Major Components subangular blocky structure parting to weak fine Blacksheep and similar soils: 60 percent granular; slightly hard, very friable, slightly sticky, Rock outcrop: 30 percent slightly plastic; many very fine and fine roots; many very fine pores; neutral; clear smooth Minor Components boundary. Cabbart and similar soils: 0 to 2 percent Bt—4 to 18 inches; light olive brown (2.5Y 5/4) sandy Areas of blowouts: 0 to 2 percent clay loam, dark grayish brown (2.5Y 4/2) moist; Soils that have slopes more than 50 percent: 0 to weak coarse prismatic structure parting to 2 percent moderate medium subangular blocky; hard, Soils that have slopes less than 25 percent: 0 to friable, moderately sticky, moderately plastic; 2 percent many very fine and fine roots; few fine and Delpoint and similar soils: 0 to 2 percent common very fine pores; many faint clay films on Major Component Description faces of peds, many distinct clay films in pores; neutral; gradual wavy boundary. Blacksheep Bk—18 to 30 inches; light brownish gray (2.5Y 6/2) Surface layer texture: Fine sandy loam loam, grayish brown (2.5Y 5/2) moist; moderate Depth class: Shallow (10 to 20 inches) coarse subangular blocky structure; hard, firm, Drainage class: Well drained slightly sticky, slightly plastic; common very fine Dominant parent material: Semiconsolidated, sandy roots; few very fine pores; common fine masses sedimentary beds of lime; violently effervescent; moderately Native plant cover type: Rangeland alkaline; gradual wavy boundary. Flooding: None Cr—30 to 60 inches; light gray (2.5Y 7/2) interbedded Available water capacity: Mainly 1.9 inches sandstone and shale that crush to sandy loam, light brownish gray (2.5Y 6/2) moist. Rock outcrop Definition: Consolidated sandstone Range in Characteristics A typical soil description with range in Soil temperature: 42 to 47 degrees F characteristics is included, in alphabetical order, Depth to the Bk horizon: 13 to 30 inches in this section. Depth to the Cr horizon: 20 to 40 inches Management A horizon For management information about this map unit, Hue: 10YR or 2.5Y see appropriate sections in Part II of this publication. Value: 5 or 6 dry; 4 or 5 moist Chroma: 2 or 3 Clay content: 18 to 27 percent Bonfri Series Content of rock fragments: 0 to 5 percent pebbles Reaction: pH 6.6 to 7.8 Depth class: Moderately deep (20 to 40 inches) Drainage class: Well drained Bt horizon Permeability: Moderately slow (0.2 to 0.6 inch/hour) Hue: 10YR or 2.5Y Landform: Sedimentary plains and hills Value: 5 or 6 dry; 4 or 5 moist Parent material: Interbedded sandstone and shale Chroma: 2 to 4 Slope range: 2 to 15 percent Texture: Clay loam, silty clay loam, or sandy clay Annual precipitation: 12 to 15 inches loam Clay content: 27 to 35 percent Taxonomic Class: Fine-loamy, mixed Typic Sand content: Greater than 15 percent fine sand Eutroboralfs or coarser Carter County, Montana—Part I 53

Content of rock fragments: 0 to 5 percent pebbles 91D—Bonfri loam, 8 to 15 percent slopes Reaction: pH 6.6 to 7.8 Bk horizon Setting Hue: 10YR or 2.5Y Landform: Hills Value: 5, 6, or 7 dry; 4, 5, or 6 moist Slope: 8 to 15 percent Chroma: 2 or 3 Mean annual precipitation: 12 to 15 inches Texture: Clay loam, loam, or sandy clay loam Clay content: 20 to 32 percent Composition Content of rock fragments: 0 to 10 percent Major Components pebbles Bonfri and similar soils: 85 percent Calcium carbonate equivalent: 5 to 15 percent Reaction: pH 7.4 to 8.4 Minor Components Weingart and similar soils: 0 to 3 percent Twilight and similar soils: 0 to 3 percent 91C—Bonfri loam, 2 to 8 percent slopes Delpoint and similar soils: 0 to 3 percent Busby and similar soils: 0 to 3 percent Setting Soils with darker colored surface layers: 0 to 3 percent Landform: Sedimentary plains Slope: 2 to 8 percent Major Component Description Mean annual precipitation: 12 to 15 inches Surface layer texture: Loam Composition Depth class: Moderately deep (20 to 40 inches) Drainage class: Well drained Major Components Dominant parent material: Interbedded sandstone Bonfri and similar soils: 85 percent and shale residuum Minor Components Native plant cover type: Rangeland Weingart and similar soils: 0 to 3 percent Flooding: None Delpoint and similar soils: 0 to 3 percent Available water capacity: Mainly 5.1 inches Twilight and similar soils: 0 to 3 percent Busby and similar soils: 0 to 3 percent A typical soil description with range in Soils with darker colored surface layers: 0 to characteristics is included, in alphabetical order, 3 percent in this section. Major Component Description Management Surface layer texture: Loam For management information about this map unit, Depth class: Moderately deep (20 to 40 inches) see appropriate sections in Part II of this publication. Drainage class: Well drained Dominant parent material: Interbedded sandstone and shale residuum 191C—Bonfri-Cambeth complex, Native plant cover type: Rangeland 2 to 8 percent slopes Flooding: None Available water capacity: Mainly 5.1 inches Setting A typical soil description with range in Landform: characteristics is included, in alphabetical order, • Bonfri—Sedimentary plains in this section. • Cambeth—Sedimentary plains Slope: Management • Bonfri—2 to 8 percent For management information about this map unit, • Cambeth—2 to 8 percent see appropriate sections in Part II of this publication. Mean annual precipitation: 12 to 15 inches 54 Soil Survey

Composition Position on landform: • Bonfri—Backslopes and shoulders Major Components • Cabbart—Shoulders and summits Bonfri and similar soils: 50 percent Slope: Cambeth and similar soils: 35 percent • Bonfri—8 to 15 percent Minor Components • Cabbart—8 to 15 percent Cabbart and similar soils: 0 to 4 percent Mean annual precipitation: 12 to 15 inches Twilight and similar soils: 0 to 4 percent Busby and similar soils: 0 to 3 percent Composition Weingart and similar soils: 0 to 2 percent Soils with darker colored surface layers: 0 to Major Components 1 percent Bonfri and similar soils: 50 percent Soils that have slopes more than 8 percent: 0 to Cabbart and similar soils: 35 percent 1 percent Minor Components Major Component Description Very shallow loamy soils: 0 to 3 percent Deep loamy soils: 0 to 3 percent Bonfri Weingart and similar soils: 0 to 3 percent Surface layer texture: Loam Twilight and similar soils: 0 to 3 percent Depth class: Moderately deep (20 to 40 inches) Soils with darker colored surface layers: 0 to Drainage class: Well drained 3 percent Dominant parent material: Interbedded sandstone and shale residuum Major Component Description Native plant cover type: Rangeland Flooding: None Bonfri Available water capacity: Mainly 5.1 inches Surface layer texture: Loam Depth class: Moderately deep (20 to 40 inches) Cambeth Drainage class: Well drained Surface layer texture: Silt loam Dominant parent material: Interbedded sandstone Depth class: Moderately deep (20 to 40 inches) and shale residuum Drainage class: Well drained Native plant cover type: Rangeland Dominant parent material: Semiconsolidated, loamy Flooding: None sedimentary beds Available water capacity: Mainly 5.1 inches Native plant cover type: Rangeland Flooding: None Available water capacity: Mainly 5.6 inches Cabbart Surface layer texture: Loam A typical soil description with range in Depth class: Shallow (10 to 20 inches) characteristics is included, in alphabetical order, Drainage class: Well drained in this section. Dominant parent material: Semiconsolidated, loamy sedimentary beds Management Native plant cover type: Rangeland For management information about this map unit, Flooding: None see appropriate sections in Part II of this publication. Available water capacity: Mainly 2.2 inches

291D—Bonfri-Cabbart loams, A typical soil description with range in 8 to 15 percent slopes characteristics is included, in alphabetical order, in this section. Setting Management Landform: • Bonfri—Hills For management information about this map unit, • Cabbart—Hills see appropriate sections in Part II of this publication. Carter County, Montana—Part I 55

391C—Bonfri-Parchin complex, Management 2 to 8 percent slopes For management information about this map unit, see appropriate sections in Part II of this publication. Setting Landform: Broadus Series • Bonfri—Sedimentary plains • Parchin—Sedimentary plains Depth class: Very deep (more than 60 inches) Slope: Drainage class: Well drained • Bonfri—2 to 8 percent Permeability: Moderate (0.6 to 2.0 inches/hour) • Parchin—2 to 8 percent Landform: Hills Mean annual precipitation: 12 to 15 inches Parent material: Colluvium Slope range: 8 to 65 percent Composition Annual precipitation: 15 to 17 inches Major Components Bonfri and similar soils: 45 percent Taxonomic Class: Fine-loamy, mixed, frigid Typic Parchin and similar soils: 40 percent Ustochrepts Minor Components Typical Pedon Archin and similar soils: 0 to 3 percent Broadus loam, in an area of Broadus-Ridge-Reeder Delpoint and similar soils: 0 to 3 percent complex, 8 to 25 percent slopes, in an area of Weingart and similar soils: 0 to 3 percent forestland, 1,500 feet north and 300 feet east of the Marvan and similar soils: 0 to 2 percent southwest corner of sec. 5, T. 8 S., R. 55 E. Cabbart and similar soils: 0 to 2 percent Soils that have slopes more than 8 percent: 0 to Oi—1 inch to 0; slightly decomposed forest litter. 2 percent A—0 to 4 inches; light yellowish brown (10YR 6/4) loam, grayish brown (10YR 5/2) moist; weak fine Major Component Description granular structure; soft, friable, slightly sticky, Bonfri slightly plastic; many fine roots; many fine tubular Surface layer texture: Loam pores; neutral; clear smooth boundary. Depth class: Moderately deep (20 to 40 inches) Bw—4 to 12 inches; pale brown (10YR 6/3) loam, Drainage class: Well drained grayish brown (10YR 5/2) moist; moderate Dominant parent material: Interbedded sandstone medium prismatic structure parting to strong and shale residuum medium subangular blocky; slightly hard, friable, Native plant cover type: Rangeland slightly sticky, slightly plastic; many fine roots; few Flooding: None fine and many very fine tubular pores; slightly Available water capacity: Mainly 5.1 inches effervescent; slightly alkaline; clear smooth boundary. Parchin Bk1—12 to 18 inches; light brownish gray (2.5Y 6/2) Surface layer texture: Fine sandy loam loam, grayish brown (2.5Y 5/2) moist; moderate Depth class: Moderately deep (20 to 40 inches) medium prismatic structure parting to moderate Drainage class: Well drained medium subangular blocky; slightly hard, friable, Dominant parent material: Semiconsolidated, loamy slightly sticky, slightly plastic; few fine and many sedimentary beds very fine roots; many fine tubular pores; many Native plant cover type: Rangeland fine masses of lime; violently effervescent; slightly Flooding: None alkaline; gradual smooth boundary. Sodium affected: Sodic within 30 inches Bk2—18 to 34 inches; light brownish gray (2.5Y 6/2) Available water capacity: Mainly 4.0 inches silty clay loam, grayish brown (2.5Y 5/2) moist; weak coarse prismatic structure; slightly hard, A typical soil description with range in friable, moderately sticky, moderately plastic; characteristics is included, in alphabetical order, common fine and medium roots; many fine in this section. tubular pores; many medium and coarse masses 56 Soil Survey

of lime; violently effervescent; moderately 126D—Broadus-Ridge-Reeder complex, alkaline; gradual smooth boundary. 8 to 25 percent slopes Bk3—34 to 60 inches; light gray (2.5Y 7/2) silt loam, dark grayish brown (2.5Y 4/2) moist; moderate Setting medium prismatic structure; slightly hard, friable, moderately sticky, moderately plastic; many Landform: medium roots; many fine tubular pores; many • Broadus—Hills medium and coarse masses of lime; violently • Ridge—Hills effervescent; moderately alkaline. • Reeder—Hills Position on landform: Range in Characteristics • Broadus—Backslopes Soil temperature: 41 to 47 degrees F • Ridge—Shoulders and summits Depth to the Bk horizon: 11 to 15 inches • Reeder—Footslopes Slope: A horizon • Broadus—8 to 25 percent Hue: 10YR, 2.5Y, or 5Y • Ridge—8 to 25 percent Value: 4, 5, or 6 dry; 3, 4, or 5 moist • Reeder—8 to 25 percent Chroma: 2 to 4 Mean annual precipitation: 15 to 17 inches Clay content: 18 to 27 percent Reaction: pH 6.6 to 7.8 Composition Bw horizon Major Components Hue: 10YR, 2.5Y, or 5Y Broadus and similar soils: 40 percent Value: 5 or 6 dry; 4 or 5 moist Ridge and similar soils: 30 percent Chroma: 2 or 3 Reeder and similar soils: 20 percent Texture: Loam, clay loam, or silty clay loam Clay content: 18 to 35 percent Minor Components Sand content: 15 to 35 percent fine and medium Cabba and similar soils: 0 to 3 percent sand Dast and similar soils: 0 to 3 percent Reaction: pH 7.4 to 7.8 Twilight and similar soils: 0 to 2 percent Areas of rock outcrop: 0 to 2 percent Bk1 horizon Hue: 10YR, 2.5Y, or 5Y Major Component Description Value: 6 dry; 5 or 6 moist Chroma: 2 or 3 Broadus Texture: Loam, clay loam, or silty clay loam Surface layer texture: Loam Clay content: 18 to 35 percent Depth class: Very deep (more than 60 inches) Sand content: 15 to 35 percent fine and medium Drainage class: Well drained sand Dominant parent material: Colluvium Calcium carbonate equivalent: 5 to 15 percent Native plant cover type: Forestland Reaction: pH 7.4 to 8.4 Flooding: None Bk2 and Bk3 horizon Available water capacity: Mainly 10.2 inches Hue: 10YR, 2.5Y, or 5Y Value: 6 or 7 dry; 4, 5, or 6 moist Ridge Chroma: 2 or 3 Surface layer texture: Sandy loam Texture: Loam, silt loam, clay loam, or silty clay Depth class: Shallow (10 to 20 inches) loam Drainage class: Well drained Clay content: 18 to 35 percent Dominant parent material: Semiconsolidated, sandy Sand content: 15 to 35 percent fine and medium sedimentary beds sand Native plant cover type: Forestland Calcium carbonate equivalent: 5 to 15 percent Flooding: None Reaction: pH 7.4 to 8.4 Available water capacity: Mainly 2.2 inches Carter County, Montana—Part I 57

Reeder Flooding: None Surface layer texture: Loam Available water capacity: Mainly 10.2 inches Depth class: Moderately deep (20 to 40 inches) Drainage class: Well drained Ridge Dominant parent material: Semiconsolidated, loamy Surface layer texture: Sandy loam sedimentary beds Depth class: Shallow (10 to 20 inches) Native plant cover type: Rangeland Drainage class: Well drained Flooding: None Dominant parent material: Semiconsolidated, sandy Available water capacity: Mainly 4.8 inches sedimentary beds Native plant cover type: Forestland A typical soil description with range in Flooding: None characteristics is included, in alphabetical order, Available water capacity: Mainly 2.2 inches in this section. Rock outcrop Management Definition: Consolidated sandstone For management information about this map unit, see appropriate sections in Part II of this publication. A typical soil description with range in characteristics is included, in alphabetical order, in this section. 126F—Broadus-Ridge-Rock outcrop complex, 25 to 65 percent slopes Management For management information about this map unit, Setting see appropriate sections in Part II of this publication. Landform: • Broadus—Hills Bullock Series • Ridge—Hills • Rock outcrop—Hills Depth class: Moderately deep (20 to 40 inches) Position on landform: Drainage class: Well drained • Broadus—Backslopes Permeability: Slow (0.06 to 0.2 inch/hour) • Ridge—Shoulders and summits Landform: Sedimentary plains • Rock outcrop—Summits Parent material: Semiconsolidated, loamy Slope: sedimentary beds • Broadus—25 to 65 percent Slope range: 2 to 8 percent • Ridge—25 to 65 percent Annual precipitation: 12 to 15 inches Mean annual precipitation: 15 to 17 inches Taxonomic Class: Fine-loamy, mixed Borollic Composition Natrargids Major Components Typical Pedon Broadus and similar soils: 30 percent Ridge and similar soils: 30 percent Bullock clay loam, in an area of Parchin-Bullock Rock outcrop: 30 percent complex, 2 to 8 percent slopes, in an area of rangeland, 2,000 feet south and 1,000 feet east of Minor Components the northwest corner of sec. 34, T. 2 N., R. 55 E. Cabba and similar soils: 0 to 4 percent Dast and similar soils: 0 to 3 percent E—0 to 2 inches; light brownish gray (10YR 6/2) fine Moderately deep loamy soils: 0 to 3 percent sandy loam, dark grayish brown (10YR 4/2) moist; weak thin platy structure parting to weak Major Component Description fine granular; soft, very friable, nonsticky, Broadus nonplastic; many very fine roots; few very fine Surface layer texture: Loam and fine pores; slightly alkaline; abrupt smooth Depth class: Very deep (more than 60 inches) boundary. Drainage class: Well drained Btn1—2 to 6 inches; brown (10YR 5/3) clay loam, Dominant parent material: Colluvium brown (10YR 4/3) moist; moderate medium Native plant cover type: Forestland columnar structure parting to moderate medium 58 Soil Survey

subangular blocky; hard, firm, moderately sticky, Chroma: 2 to 4 very plastic; many very fine and fine roots; few Texture: Clay loam or sandy clay loam very fine pores; few faint clay films on faces of Clay content: 27 to 35 percent peds and in pores; moderately alkaline; gradual Electrical conductivity: 2 to 8 mmhos/cm smooth boundary. Sodium adsorption ratio: 13 to 30 Btn2—6 to 12 inches; brown (10YR 5/3) clay loam, Reaction: pH 7.8 to 9.6 brown (10YR 4/3) moist; moderate medium Bkz and Bky horizons prismatic structure parting to moderate fine and Hue: 10YR, 2.5Y, or 5Y medium subangular blocky; hard, firm, Value: 5, 6, or 7 dry; 4 or 5 moist moderately sticky, very plastic; few fine and Chroma: 1 to 4 common very fine roots; few very fine pores; few Texture: Clay loam, sandy clay loam, or loam faint clay films on faces of peds and in pores; Clay content: 25 to 32 percent strongly alkaline; clear smooth boundary. Electrical conductivity: 4 to 16 mmhos/cm Bkz—12 to 25 inches; light yellowish brown (2.5Y 6/4) Sodium adsorption ratio: 20 to 40 clay loam, dark grayish brown (2.5Y 4/2) moist; Calcium carbonate equivalent: 5 to 15 percent weak medium subangular blocky structure; Reaction: pH 7.8 to 9.6 slightly hard, friable, moderately sticky, moderately plastic; few very fine and fine roots; few very fine pores; few fine nests of salt crystals; disseminated lime; few fine threads of lime; Busby Series violently effervescent; strongly alkaline; clear Depth class: Very deep (more than 60 inches) wavy boundary. Drainage class: Well drained Bky—25 to 35 inches; light brownish gray (2.5Y 6/2) Permeability: Moderately rapid (2.0 to 6.0 inches/ clay loam, dark grayish brown (2.5Y 4/2) moist; hour) massive; slightly hard, friable, moderately sticky, Landform: Sedimentary plains and hills moderately plastic; few very fine and fine roots; Parent material: Alluvium few very fine pores; few fine soft masses of Slope range: 2 to 15 percent gypsum; common medium masses of lime and Annual precipitation: 12 to 15 inches few fine seams of lime; violently effervescent; strongly alkaline; gradual wavy boundary. Taxonomic Class: Coarse-loamy, mixed, frigid Aridic Cr—35 to 60 inches; light brownish gray (2.5Y 6/2) Ustochrepts semiconsolidated, loamy sedimentary beds that crush to silty clay loam, grayish brown (2.5Y 5/2) Typical Pedon moist. Busby fine sandy loam, in an area of Busby- Range in Characteristics Blacksheep-Twilight fine sandy loams, 8 to 25 percent slopes, in an area of rangeland, 2,200 feet Depth to the Bkz horizon: 10 to 15 inches south and 2,000 feet west of the northeast corner of Depth to the Cr horizon: 20 to 40 inches sec. 32, T. 2 S., R. 56 E. Other features: A clay loam texture results from mixing the E and Btn horizons in areas that are A—0 to 4 inches; grayish brown (2.5Y 5/2) fine sandy cultivated. loam, very dark grayish brown (2.5Y 3/2) moist; Taxonomic note: Bullock soil is a taxadjunct to the weak fine granular structure; soft, very friable, series. It classifies as Fine-loamy, mixed Typic nonsticky, nonplastic; common very fine and fine Natriboralfs. Use and management are similar. roots; slightly alkaline; clear smooth boundary. Bw—4 to 12 inches; light brownish gray (2.5Y 6/2) E horizon fine sandy loam, dark grayish brown (2.5Y 4/2) Hue: 10YR or 2.5Y moist; weak medium subangular blocky structure; Value: 5 to 7 dry; 3 or 4 moist soft, very friable, nonsticky, nonplastic; common Chroma: 1 or 2 very fine and fine roots; few very fine pores; Texture: Clay loam when mixed to 7 inches slightly alkaline; clear wavy boundary. Clay content: 5 to 10 percent Bk1—12 to 23 inches; light brownish gray (2.5Y 6/2) Reaction: pH 7.4 to 7.8 fine sandy loam, grayish brown (2.5Y 5/2) moist; Btn horizons weak fine and medium subangular blocky Hue: 10YR or 2.5Y structure; slightly hard, very friable, nonsticky, Value: 5 or 6 dry; 4 or 5 moist nonplastic; common very fine and fine roots; few Carter County, Montana—Part I 59

very fine pores; few very fine masses, seams, 70C—Busby fine sandy loam, and threads of lime; strongly effervescent; 2 to 8 percent slopes moderately alkaline; clear wavy boundary. Bk2—23 to 46 inches; light brownish gray (2.5Y 6/2) Setting fine sandy loam, grayish brown (2.5Y 5/2) moist; weak fine subangular blocky structure; soft, very Landform: Sedimentary plains friable, nonsticky, nonplastic; few very fine roots; Slope: 2 to 8 percent few very fine pores; few very fine and medium Mean annual precipitation: 12 to 15 inches masses of lime; strongly effervescent; moderately Composition alkaline; clear smooth boundary. C—46 to 60 inches; light brownish gray (2.5Y 6/2) Major Components loamy fine sand, grayish brown (2.5Y 5/2) moist; Busby and similar soils: 85 percent massive; loose, nonsticky, nonplastic; moderately Minor Components alkaline. Blacksheep and similar soils: 0 to 3 percent Range in Characteristics Chinook and similar soils: 0 to 3 percent Twilight and similar soils: 0 to 3 percent Soil temperature: 42 to 47 degrees F Yamacall and similar soils: 0 to 3 percent Depth to the Bk horizon: 10 to 16 inches Soils that have slopes less than 2 percent: 0 to Soil phases: Gullied 2 percent A horizon Soils with darker colored surface layers: 0 to Hue: 10YR or 2.5Y 1 percent Value: 5 or 6 dry; 3 or 4 moist Major Component Description Chroma: 2 to 4 Clay content: 10 to 18 percent Surface layer texture: Fine sandy loam Reaction: pH 7.4 to 8.4 Depth class: Very deep (more than 60 inches) Drainage class: Well drained Bw horizon Dominant parent material: Alluvium Hue: 10YR or 2.5Y Native plant cover type: Rangeland Value: 5 or 6 dry; 4 or 5 moist Flooding: None Chroma: 2 to 4 Available water capacity: Mainly 7.5 inches Texture: Fine sandy loam, sandy loam, or loam Clay content: 10 to 18 percent A typical soil description with range in Reaction: pH 7.4 to 8.4 characteristics is included, in alphabetical order, Bk horizons in this section. Hue: 10YR, 2.5Y, or 5Y Management Value: 5, 6, or 7 dry; 4, 5, or 6 moist Chroma: 2 to 4 For management information about this map unit, Texture: Fine sandy loam or sandy loam see appropriate sections in Part II of this publication. Clay content: 10 to 18 percent Calcium carbonate equivalent: 5 to 15 percent Reaction: pH 7.4 to 8.4 70D—Busby fine sandy loam, 8 to 15 percent slopes C horizon Hue: 10YR or 2.5Y Setting Value: 6 or 7 dry; 5 or 6 moist Chroma: 2 to 4 Landform: Hills Texture: Fine sandy loam, sandy loam, loamy fine Slope: 8 to 15 percent sand, loamy sand, or fine sand (The loamy fine Mean annual precipitation: 12 to 15 inches sand, loamy sand, or fine sand textures are Composition below depths of 40 inches.) Clay content: 3 to 18 percent Major Components Reaction: pH 7.9 to 8.4 Busby and similar soils: 85 percent 60 Soil Survey

Minor Components Very shallow loamy soils: 0 to 3 percent Blacksheep and similar soils: 0 to 3 percent Areas of rock outcrop: 0 to 2 percent Chinook and similar soils: 0 to 3 percent Areas of blowouts: 0 to 2 percent Twilight and similar soils: 0 to 3 percent Soils with darker colored surface layers: 0 to Cabbart and similar soils: 0 to 3 percent 2 percent Delpoint and similar soils: 0 to 2 percent Major Component Description Soils with darker colored surface layers: 0 to 1 percent Busby Surface layer texture: Fine sandy loam Major Component Description Depth class: Very deep (more than 60 inches) Surface layer texture: Fine sandy loam Drainage class: Well drained Depth class: Very deep (more than 60 inches) Dominant parent material: Alluvium Drainage class: Well drained Native plant cover type: Rangeland Dominant parent material: Alluvium Flooding: None Native plant cover type: Rangeland Available water capacity: Mainly 7.5 inches Flooding: None Available water capacity: Mainly 7.5 inches Blacksheep Surface layer texture: Fine sandy loam A typical soil description with range in Depth class: Shallow (10 to 20 inches) characteristics is included, in alphabetical order, Drainage class: Well drained in this section. Dominant parent material: Semiconsolidated, sandy sedimentary beds Management Native plant cover type: Rangeland Flooding: None For management information about this map unit, Available water capacity: Mainly 2.3 inches see appropriate sections in Part II of this publication. Twilight 170D—Busby-Blacksheep-Twilight fine Surface layer texture: Fine sandy loam sandy loams, 8 to 25 percent slopes Depth class: Moderately deep (20 to 40 inches) Drainage class: Well drained Dominant parent material: Semiconsolidated, sandy Setting sedimentary beds Landform: Native plant cover type: Rangeland • Busby—Hills Flooding: None • Blacksheep—Hills Available water capacity: Mainly 4.2 inches • Twilight—Hills Position on landform: A typical soil description with range in • Busby—Backslopes and footslopes characteristics is included, in alphabetical order, • Blacksheep—Shoulders and summits in this section. • Twilight—Backslopes and footslopes Management Slope: • Busby—8 to 15 percent For management information about this map unit, • Blacksheep—8 to 25 percent see appropriate sections in Part II of this publication. • Twilight—8 to 25 percent Mean annual precipitation: 12 to 15 inches Composition 170E—Busby-Blacksheep-Rock outcrop complex, 8 to 25 percent slopes Major Components Busby and similar soils: 40 percent Blacksheep and similar soils: 30 percent Setting Twilight and similar soils: 15 percent Landform: Minor Components • Busby—Hills Cabbart and similar soils: 0 to 3 percent • Blacksheep—Hills Delpoint and similar soils: 0 to 3 percent • Rock outcrop—Hills Carter County, Montana—Part I 61

Position on landform: 270E—Busby, gullied-Delpoint-Yawdim • Busby—Footslopes and toeslopes complex, 8 to 25 percent slopes • Blacksheep—Shoulders and summits • Rock outcrop—Summits Setting Slope: • Busby—8 to 15 percent Landform: • Blacksheep—8 to 25 percent • Busby—Hills Mean annual precipitation: 12 to 15 inches • Delpoint—Hills • Yawdim—Hills Composition Position on landform: Major Components • Busby—Backslopes and footslopes Busby and similar soils: 40 percent • Delpoint—Backslopes Blacksheep and similar soils: 30 percent • Yawdim—Shoulders and summits Rock outcrop: 20 percent Slope: • Busby—8 to 15 percent Minor Components • Delpoint—8 to 25 percent Cabbart and similar soils: 0 to 2 percent • Yawdim—8 to 25 percent Twilight and similar soils: 0 to 2 percent Mean annual precipitation: 12 to 15 inches Chinook and similar soils: 0 to 2 percent Areas of blowouts: 0 to 2 percent Composition Yamacall and similar soils: 0 to 1 percent Major Components Delpoint and similar soils: 0 to 1 percent Busby and similar soils: 35 percent Major Component Description Delpoint and similar soils: 30 percent Yawdim and similar soils: 20 percent Busby Surface layer texture: Fine sandy loam Minor Components Depth class: Very deep (more than 60 inches) Archin and similar soils: 0 to 3 percent Drainage class: Well drained Cabbart and similar soils: 0 to 3 percent Dominant parent material: Alluvium Areas of rock outcrop: 0 to 3 percent Native plant cover type: Rangeland Weingart and similar soils: 0 to 3 percent Flooding: None Yamacall and similar soils: 0 to 2 percent Available water capacity: Mainly 7.5 inches Poorly drained soils: 0 to 1 percent

Blacksheep Major Component Description Surface layer texture: Fine sandy loam Depth class: Shallow (10 to 20 inches) Busby Drainage class: Well drained Surface layer texture: Fine sandy loam Dominant parent material: Semiconsolidated, sandy Depth class: Very deep (more than 60 inches) sedimentary beds Drainage class: Well drained Native plant cover type: Rangeland Dominant parent material: Alluvium Flooding: None Native plant cover type: Rangeland Available water capacity: Mainly 2.3 inches Flooding: None Available water capacity: Mainly 7.5 inches Rock outcrop Definition: Consolidated sandstone Delpoint Surface layer texture: Loam A typical soil description with range in Depth class: Moderately deep (20 to 40 inches) characteristics is included, in alphabetical order, Drainage class: Well drained in this section. Dominant parent material: Semiconsolidated, loamy sedimentary beds Management Native plant cover type: Rangeland For management information about this map unit, Flooding: None see appropriate sections in Part II of this publication. Available water capacity: Mainly 4.7 inches 62 Soil Survey

Yawdim common very fine roots; few very fine pores; Surface layer texture: Silty clay loam disseminated lime; strongly effervescent; Depth class: Shallow (10 to 20 inches) moderately alkaline; gradual smooth boundary. Drainage class: Well drained Cr—16 to 60 inches; pale yellow (2.5Y 7/4) Dominant parent material: Semiconsolidated shale semiconsolidated loamy sedimentary beds that residuum crush to loam, light yellowish brown (2.5Y 6/4) Native plant cover type: Rangeland moist. Flooding: None Range in Characteristics Available water capacity: Mainly 2.5 inches Soil temperature: 42 to 47 degrees F A typical soil description with range in Depth to the Cr horizon: 10 to 20 inches characteristics is included, in alphabetical order, Soil phases: Stony; the hard rock fragments in the in this section. stony and gravelly phases are mainly surficial deposits. Management A horizon For management information about this map unit, Hue: 10YR or 2.5Y see appropriate sections in Part II of this publication. Value: 3, 4, 5, or 6 dry; 3 or 4 moist Chroma: 1 to 4 Texture: Loam or silt loam Cabba Series Clay content: 10 to 27 percent Content of rock fragments: 0 to 60 percent—0 to Depth class: Shallow (10 to 20 inches) 40 percent boulders, stones, or cobbles; 0 to Drainage class: Well drained 30 percent pebbles or channers Permeability: Moderate (0.6 to 2.0 inches/hour) Content of rock fragments, surface cover: 0 to Landform: Sedimentary plains and hills 0.1 percent stones Parent material: Semiconsolidated, loamy Electrical conductivity: 0 to 4 mmhos/cm sedimentary beds Reaction: pH 7.4 to 9.0 Slope range: 4 to 60 percent Annual precipitation: 15 to 17 inches Bk and C horizons Hue: 10YR, 2.5Y, or 5Y Taxonomic Class: Loamy, mixed (calcareous), frigid, Value: 5, 6, 7, or 8 dry; 4, 5, 6, or 7 moist shallow Typic Ustorthents Chroma: 1 to 4 or 6 Texture: Loam, silt loam, clay loam, or silty clay Typical Pedon loam Cabba loam, in an area of Reeder-Cabba loams, 4 to Clay content: 20 to 35 percent 15 percent slopes, in an area of rangeland, 2,000 feet Content of rock fragments: 0 to 35 percent—0 to north and 1,600 feet east of the southwest corner of 5 percent cobbles; 0 to 30 percent pebbles or sec. 4, T. 2 S., R. 61 E. channers Calcium carbonate equivalent: 5 to 15 percent A—0 to 3 inches; light yellowish brown (2.5Y 6/4) Electrical conductivity: 0 to 8 mmhos/cm loam, olive brown (2.5Y 4/4) moist; weak fine Reaction: pH 7.4 to 9.0 granular structure; soft, very friable, slightly sticky, slightly plastic; common fine and many very fine roots; disseminated lime; strongly effervescent; 112D—Cabba silt loam, slightly alkaline; clear smooth boundary. 8 to 15 percent slopes Bk—3 to 7 inches; pale brown (10YR 6/3) loam, light olive brown (2.5Y 5/4) moist; weak thick platy Setting structure; soft, friable, slightly sticky, slightly plastic; few fine and common very fine roots; few Landform: Hills very fine pores; few fine and medium masses of Slope: 8 to 15 percent lime; violently effervescent; slightly alkaline; clear Mean annual precipitation: 15 to 17 inches wavy boundary. Composition C—7 to 16 inches; pale yellow (2.5Y 7/4) loam, light olive brown (2.5Y 5/4) moist; massive; soft, very Major Components friable, slightly sticky, slightly plastic; few fine and Cabba and similar soils: 85 percent Carter County, Montana—Part I 63

Minor Components Dominant parent material: Semiconsolidated, loamy Very shallow loamy soils: 0 to 4 percent sedimentary beds Dast and similar soils: 0 to 4 percent Native plant cover type: Rangeland Moderately deep loamy soils: 0 to 4 percent Flooding: None Areas of rock outcrop: 0 to 3 percent Available water capacity: Mainly 2.7 inches Major Component Description Rock outcrop Surface layer texture: Silt loam Definition: Consolidated sandstone and shale Depth class: Shallow (10 to 20 inches) Drainage class: Well drained A typical soil description with range in Dominant parent material: Semiconsolidated, loamy characteristics is included, in alphabetical order, sedimentary beds in this section. Native plant cover type: Rangeland Management Flooding: None Available water capacity: Mainly 2.7 inches For management information about this map unit, see appropriate sections in Part II of this publication. A typical soil description with range in characteristics is included, in alphabetical order, in this section. 312D—Cabba-Dast complex, Management 8 to 15 percent slopes For management information about this map unit, Setting see appropriate sections in Part II of this publication. Landform: • Cabba—Hills 212E—Cabba-Rock outcrop complex, • Dast—Hills 15 to 45 percent slopes Position on landform: • Cabba—Shoulders and summits • Dast—Backslopes and footslopes Setting Slope: Landform: • Cabba—8 to 15 percent • Cabba—Hills • Dast—8 to 15 percent • Rock outcrop—Hills Mean annual precipitation: 15 to 17 inches Position on landform: Composition • Cabba—Backslopes • Rock outcrop—Summits Major Components Slope: 15 to 45 percent Cabba and similar soils: 50 percent Mean annual precipitation: 15 to 17 inches Dast and similar soils: 35 percent Composition Minor Components Very shallow sandy soils: 0 to 5 percent Major Components Moderately deep loamy soils: 0 to 5 percent Cabba and similar soils: 50 percent Very deep silt loam soils: 0 to 5 percent Rock outcrop: 35 percent Major Component Description Minor Components Dast and similar soils: 0 to 5 percent Cabba Very shallow loamy soils: 0 to 5 percent Surface layer texture: Silt loam Moderately deep loamy soils: 0 to 5 percent Depth class: Shallow (10 to 20 inches) Drainage class: Well drained Major Component Description Dominant parent material: Semiconsolidated, loamy Cabba sedimentary beds Surface layer texture: Silt loam Native plant cover type: Rangeland Depth class: Shallow (10 to 20 inches) Flooding: None Drainage class: Well drained Available water capacity: Mainly 2.7 inches 64 Soil Survey

Dast Range in Characteristics Surface layer texture: Sandy loam Soil temperature: 42 to 47 degrees F Depth class: Moderately deep (20 to 40 inches) Depth to the Cr horizon: 10 to 20 inches Drainage class: Well drained Dominant parent material: Semiconsolidated, sandy A horizon sedimentary beds Hue: 10YR, 2.5Y, or 5Y Flooding: None Value: 5, 6, or 7 dry; 3, 4, or 5 moist Available water capacity: Mainly 3.6 inches Chroma: 2 to 4 Texture: Loam or silt loam A typical soil description with range in Clay content: 18 to 27 percent characteristics is included, in alphabetical order, Electrical conductivity: 0 to 4 mmhos/cm in this section. Calcium carbonate equivalent: 5 to 10 percent Reaction: pH 7.4 to 9.0 Management Bk horizon For management information about this map unit, Hue: 10YR, 2.5Y, or 5Y see appropriate sections in Part II of this publication. Value: 5, 6, 7, or 8 dry; 4, 5, or 6 moist Chroma: 2 to 4 Cabbart Series Texture: Loam or silt loam Clay content: 18 to 27 percent Depth class: Shallow (10 to 20 inches) Electrical conductivity: 0 to 4 mmhos/cm Drainage class: Well drained Sodium adsorption ratio: 1 to 5 Permeability: Moderate (0.6 to 2.0 inches/hour) Calcium carbonate equivalent: 10 to 15 percent Landform: Sedimentary plains and hills Reaction: pH 7.4 to 9.0 Parent material: Semiconsolidated, loamy sedimentary beds Slope range: 2 to 70 percent 60D—Cabbart silt loam, Annual precipitation: 12 to 15 inches 4 to 15 percent slopes Taxonomic Class: Loamy, mixed (calcareous), frigid, Setting shallow Aridic Ustorthents Landform: Sedimentary plains and hills Typical Pedon Slope: 4 to 15 percent Cabbart loam, in an area of Cabbart-Rock outcrop- Mean annual precipitation: 12 to 15 inches Delpoint complex, 15 to 50 percent slopes, in an area Composition of rangeland, 2,100 feet south and 1,000 feet east of the northwest corner of sec. 15, T. 4 N., R. 57 E. Major Components Cabbart and similar soils: 85 percent A—0 to 3 inches; light yellowish brown (2.5Y 6/4) loam, light olive brown (2.5Y 5/4) moist; weak Minor Components medium subangular blocky structure; soft, very Blacksheep and similar soils: 0 to 4 percent friable, slightly sticky, slightly plastic; many very Delpoint and similar soils: 0 to 4 percent fine and fine roots; few very fine and fine pores; Very shallow loamy soils: 0 to 4 percent violently effervescent; moderately alkaline; clear Areas of rock outcrop: 0 to 2 percent smooth boundary. Soils that have slopes more than 15 percent: 0 to Bk—3 to 12 inches; pale yellow (2.5Y 7/4) loam, light 1 percent olive brown (2.5Y 5/4) moist; weak coarse Major Component Description subangular blocky structure; soft, very friable, slightly sticky, slightly plastic; many very fine Surface layer texture: Silt loam roots; few very fine pores; common fine and Depth class: Shallow (10 to 20 inches) medium masses of lime; violently effervescent; Drainage class: Well drained moderately alkaline; clear wavy boundary. Dominant parent material: Semiconsolidated, loamy Cr—12 to 60 inches; pale yellow (2.5Y 7/4) sedimentary beds semiconsolidated, loamy sedimentary beds that Native plant cover type: Rangeland crush to silt loam, light yellowish brown (2.5Y 6/4) Flooding: None moist. Available water capacity: Mainly 2.2 inches Carter County, Montana—Part I 65

A typical soil description with range in Drainage class: Well drained characteristics is included, in alphabetical order, Dominant parent material: Semiconsolidated, loamy in this section. sedimentary beds Native plant cover type: Rangeland Management Flooding: None For management information about this map unit, Available water capacity: Mainly 4.7 inches see appropriate sections in Part II of this publication. A typical soil description with range in characteristics is included, in alphabetical order, 160E—Cabbart-Rock outcrop-Delpoint in this section. complex, 15 to 50 percent slopes Management Setting For management information about this map unit, see appropriate sections in Part II of this publication. Landform: • Cabbart—Hills • Rock outcrop—Hills • Delpoint—Hills 160F—Cabbart-Rock outcrop-Yawdim Position on landform: complex, 15 to 70 percent slopes • Cabbart—Backslopes and shoulders • Rock outcrop—Summits Setting • Delpoint—Backslopes Slope: Landform: • Cabbart—15 to 50 percent • Cabbart—Hills • Delpoint—15 to 25 percent • Rock outcrop—Hills Mean annual precipitation: 12 to 15 inches • Yawdim—Hills Position on landform: Composition • Cabbart—Backslopes and shoulders Major Components • Rock outcrop—Summits Cabbart and similar soils: 50 percent • Yawdim—Backslopes and footslopes Rock outcrop: 20 percent Slope: Delpoint and similar soils: 15 percent • Cabbart—15 to 70 percent • Yawdim—15 to 70 percent Minor Components Mean annual precipitation: 12 to 15 inches Weingart and similar soils: 0 to 5 percent Very shallow loamy soils: 0 to 5 percent Composition Yamacall and similar soils: 0 to 4 percent Major Components Poorly drained soils: 0 to 1 percent Cabbart and similar soils: 35 percent Major Component Description Rock outcrop: 25 percent Yawdim and similar soils: 25 percent Cabbart Surface layer texture: Loam Minor Components Depth class: Shallow (10 to 20 inches) Delpoint and similar soils: 0 to 4 percent Drainage class: Well drained Very shallow loamy soils: 0 to 4 percent Dominant parent material: Semiconsolidated, loamy Soils that have slopes less than 15 percent: 0 to sedimentary beds 4 percent Native plant cover type: Rangeland Weingart and similar soils: 0 to 3 percent Flooding: None Major Component Description Available water capacity: Mainly 2.2 inches Cabbart Rock outcrop Surface layer texture: Loam Definition: Consolidated sedimentary beds Depth class: Shallow (10 to 20 inches) Drainage class: Well drained Delpoint Dominant parent material: Semiconsolidated, loamy Surface layer texture: Loam sedimentary beds Depth class: Moderately deep (20 to 40 inches) Native plant cover type: Rangeland 66 Soil Survey

Flooding: None Major Component Description Available water capacity: Mainly 2.2 inches Cabbart Surface layer texture: Silt loam Rock outcrop Depth class: Shallow (10 to 20 inches) Definition: Consolidated sedimentary beds Drainage class: Well drained Dominant parent material: Semiconsolidated, loamy Yawdim sedimentary beds Surface layer texture: Silty clay loam Native plant cover type: Rangeland Depth class: Shallow (10 to 20 inches) Flooding: None Drainage class: Well drained Available water capacity: Mainly 2.2 inches Dominant parent material: Semiconsolidated shale residuum Cambeth Native plant cover type: Rangeland Surface layer texture: Silt loam Flooding: None Depth class: Moderately deep (20 to 40 inches) Available water capacity: Mainly 2.5 inches Drainage class: Well drained Dominant parent material: Semiconsolidated, loamy A typical soil description with range in sedimentary beds characteristics is included, in alphabetical order, Native plant cover type: Rangeland in this section. Flooding: None Management Available water capacity: Mainly 5.6 inches For management information about this map unit, A typical soil description with range in see appropriate sections in Part II of this publication. characteristics is included, in alphabetical order, in this section. 260D—Cabbart-Cambeth silt loams, Management 8 to 15 percent slopes For management information about this map unit, see appropriate sections in Part II of this publication. Setting Landform: 360D—Cabbart-Bascovy complex, • Cabbart—Hills 4 to 15 percent slopes • Cambeth—Hills Position on landform: Setting • Cabbart—Shoulders and summits Landform: • Cambeth—Backslopes • Cabbart—Sedimentary plains and hills Slope: • Bascovy—Sedimentary plains and hills • Cabbart—8 to 15 percent Position on landform: • Cambeth—8 to 15 percent • Cabbart—Shoulders and summits Mean annual precipitation: 12 to 15 inches • Bascovy—Backslopes and footslopes Slope: Composition • Cabbart—4 to 15 percent Major Components • Bascovy—4 to 15 percent Cabbart and similar soils: 50 percent Mean annual precipitation: 12 to 15 inches Cambeth and similar soils: 35 percent Composition Minor Components Major Components Delpoint and similar soils: 0 to 4 percent Cabbart and similar soils: 50 percent Very shallow loamy soils: 0 to 4 percent Bascovy and similar soils: 35 percent Yamacall and similar soils: 0 to 3 percent Weingart and similar soils: 0 to 2 percent Minor Components Soils that have slopes less than 8 percent: 0 to Delpoint and similar soils: 0 to 4 percent 2 percent Gerdrum and similar soils: 0 to 4 percent Carter County, Montana—Part I 67

Parchin and similar soils: 0 to 3 percent A—0 to 4 inches; brown (10YR 5/3) silt loam, brown Very shallow clayey soils: 0 to 2 percent (10YR 4/3) moist; weak medium granular Neldore and similar soils: 0 to 2 percent structure; slightly hard, friable, slightly sticky, slightly plastic; common very fine and fine roots; Major Component Description few fine pores; disseminated lime; strongly Cabbart effervescent; moderately alkaline; clear smooth Surface layer texture: Silt loam boundary. Depth class: Shallow (10 to 20 inches) Bw—4 to 12 inches; light brownish gray (2.5Y 6/2) Drainage class: Well drained silty clay loam, grayish brown (2.5Y 5/2) moist; Dominant parent material: Semiconsolidated, loamy weak medium and coarse subangular blocky sedimentary beds structure; slightly hard, friable, slightly sticky, Native plant cover type: Rangeland moderately plastic; few very fine and fine roots; Flooding: None few very fine pores; disseminated lime; strongly Available water capacity: Mainly 2.2 inches effervescent; moderately alkaline; clear smooth boundary. Bascovy Bk—12 to 32 inches; light brownish gray (2.5Y 6/2) Surface layer texture: Clay silt loam, grayish brown (2.5Y 5/2) moist; Depth class: Moderately deep (20 to 40 inches) moderate medium subangular blocky structure; Drainage class: Well drained hard, friable, slightly sticky, slightly plastic; few Dominant parent material: Semiconsolidated shale very fine roots; few very fine pores; many fine residuum masses of lime; strongly effervescent; moderately Native plant cover type: Rangeland alkaline; clear wavy boundary. Flooding: None Cr—32 to 60 inches; white (2.5Y 8/2) Sodium affected: Sodic within 30 inches semiconsolidated, loamy sedimentary beds that Available water capacity: Mainly 5.3 inches crush to silt loam, light gray (2.5Y 7/2) moist. Range in Characteristics A typical soil description with range in characteristics is included, in alphabetical order, Soil temperature: 42 to 47 degrees F in this section. Depth to the Bk horizon: 10 to 15 inches Depth to the Cr horizon: 20 to 40 inches Management Soil phases: Calcareous For management information about this map unit, A horizon see appropriate sections in Part II of this publication. Hue: 10YR or 2.5Y Value: 4, 5, or 6 dry; 3 or 4 moist Cambeth Series Chroma: 2 to 4 Clay content: 18 to 27 percent Depth class: Moderately deep (20 to 40 inches) Effervescence: None to violently Drainage class: Well drained Calcium carbonate equivalent: 0 to 10 percent Permeability: Moderate (0.6 to 2.0 inches/hour) Reaction: pH 7.4 to 8.4 Landform: Sedimentary plains and hills Bw horizon Parent material: Semiconsolidated, loamy Hue: 10YR or 2.5Y sedimentary beds Value: 5, 6, or 7 dry; 4 or 5 moist Slope range: 2 to 25 percent Chroma: 2 to 4 Annual precipitation: 12 to 15 inches Texture: Loam, silt loam, or silty clay loam Clay content: 18 to 35 percent Taxonomic Class: Fine-silty, mixed, frigid Aridic Calcium carbonate equivalent: 0 to 10 percent Ustochrepts Reaction: pH 7.4 to 8.4 Typical Pedon Bk horizon Cambeth silt loam, in an area of Yamacall-Cambeth Hue: 10YR, 2.5Y, or 5Y complex, 2 to 8 percent slopes, in an area of Value: 5, 6, or 7 dry; 4, 5, or 6 moist rangeland, 250 feet north and 1,500 feet east of the Chroma: 2 to 4 southwest corner of sec. 33, T. 8 S., R. 61 E. Texture: Loam, silt loam, or silty clay loam 68 Soil Survey

Clay content: 18 to 35 percent A typical soil description with range in Calcium carbonate equivalent: 10 to 20 percent characteristics is included, in alphabetical order, Reaction: pH 7.9 to 9.0 in this section. Management 160D—Cambeth-Yamacall complex, For management information about this map unit, 8 to 15 percent slopes see appropriate sections in Part II of this publication.

Setting 260C—Cambeth-Cabbart silt loams, Landform: 2 to 8 percent slopes • Cambeth—Hills • Yamacall—Hills Setting Position on landform: • Cambeth—Shoulders and summits Landform: • Yamacall—Backslopes and footslopes • Cambeth—Sedimentary plains Slope: • Cabbart—Sedimentary plains • Cambeth—8 to 15 percent Position on landform: Backslopes and footslopes • Yamacall—8 to 15 percent Slope: Mean annual precipitation: 12 to 15 inches • Cambeth—2 to 8 percent • Cabbart—2 to 8 percent Composition Mean annual precipitation: 12 to 15 inches Major Components Composition Cambeth and similar soils: 55 percent Yamacall and similar soils: 30 percent Major Components Cambeth and similar soils: 60 percent Minor Components Cabbart and similar soils: 25 percent Archin and similar soils: 0 to 4 percent Cabbart and similar soils: 0 to 4 percent Minor Components Soils with darker colored surface layers: 0 to Archin and similar soils: 0 to 4 percent 3 percent Twilight and similar soils: 0 to 4 percent Very shallow loamy soils: 0 to 2 percent Very shallow loamy soils: 0 to 3 percent Soils that have slopes more than 15 percent: 0 to Yamacall and similar soils: 0 to 2 percent 2 percent Soils that have slopes more than 8 percent: 0 to 2 percent Major Component Description Major Component Description Cambeth Surface layer texture: Silt loam Cambeth Depth class: Moderately deep (20 to 40 inches) Surface layer texture: Silt loam Drainage class: Well drained Depth class: Moderately deep (20 to 40 inches) Dominant parent material: Semiconsolidated, loamy Drainage class: Well drained sedimentary beds Dominant parent material: Semiconsolidated, loamy Native plant cover type: Rangeland sedimentary beds Flooding: None Native plant cover type: Rangeland Available water capacity: Mainly 5.6 inches Flooding: None Available water capacity: Mainly 5.6 inches Yamacall Surface layer texture: Silt loam Cabbart Depth class: Very deep (more than 60 inches) Surface layer texture: Silt loam Drainage class: Well drained Depth class: Shallow (10 to 20 inches) Dominant parent material: Alluvium Drainage class: Well drained Native plant cover type: Rangeland Dominant parent material: Semiconsolidated, loamy Flooding: None sedimentary beds Available water capacity: Mainly 9.7 inches Native plant cover type: Rangeland Carter County, Montana—Part I 69

Flooding: None Native plant cover type: Rangeland Available water capacity: Mainly 2.2 inches Flooding: None Available water capacity: Mainly 4.5 inches A typical soil description with range in characteristics is included, in alphabetical order, Cabbart in this section. Surface layer texture: Silt loam Depth class: Shallow (10 to 20 inches) Management Drainage class: Well drained For management information about this map unit, Dominant parent material: Semiconsolidated, loamy see appropriate sections in Part II of this publication. sedimentary beds Native plant cover type: Rangeland Flooding: None 260E—Cambeth-Cabbart-Yawdim Available water capacity: Mainly 2.6 inches complex, 15 to 25 percent slopes Yawdim Setting Surface layer texture: Silty clay loam Depth class: Shallow (10 to 20 inches) Landform: Drainage class: Well drained • Cambeth—Hills Dominant parent material: Semiconsolidated shale • Cabbart—Hills residuum • Yawdim—Hills Native plant cover type: Rangeland Position on landform: Flooding: None • Cambeth—Backslopes and footslopes Available water capacity: Mainly 2.5 inches • Cabbart—Shoulders and summits • Yawdim—Shoulders and summits A typical soil description with range in Slope: characteristics is included, in alphabetical order, • Cambeth—15 to 25 percent in this section. • Cabbart—15 to 25 percent • Yawdim—15 to 25 percent Management Mean annual precipitation: 12 to 15 inches For management information about this map unit, Composition see appropriate sections in Part II of this publication. Major Components Cambeth and similar soils: 40 percent Carfall Series Cabbart and similar soils: 30 percent Yawdim and similar soils: 15 percent Depth class: Very deep (more than 60 inches) Drainage class: Well drained Minor Components Permeability: Moderate (0.6 to 2.0 inches/hour) Archin and similar soils: 0 to 3 percent Landform: Sedimentary plains and hills Very shallow loamy soils: 0 to 3 percent Parent material: Alluvium Yamacall and similar soils: 0 to 3 percent Slope range: 2 to 15 percent Areas of rock outcrop: 0 to 3 percent Annual precipitation: 12 to 15 inches Soils that have slopes more than 25 percent: 0 to 2 percent Taxonomic Class: Fine-loamy, mixed Pachic Soils that have slopes less than 15 percent: 0 to Argiborolls 1 percent Typical Pedon Major Component Description Carfall fine sandy loam, 8 to 15 percent slopes, in an Cambeth area of rangeland, 2,500 feet north and 1,600 feet Surface layer texture: Silt loam east of the southwest corner of sec. 1, T. 5 N., Depth class: Moderately deep (20 to 40 inches) R. 55 E. Drainage class: Well drained Dominant parent material: Semiconsolidated, loamy A—0 to 9 inches; grayish brown (10YR 5/2) fine sedimentary beds sandy loam, dark brown (10YR 3/3) moist; 70 Soil Survey

moderate medium granular structure; soft, very 14C—Carfall loam, 2 to 8 percent slopes friable, nonsticky, nonplastic; many very fine roots; neutral; clear smooth boundary. Setting Bt1—9 to 15 inches; brown (10YR 5/3) sandy clay loam, dark brown (10YR 3/3) moist; strong Landform: Sedimentary plains coarse prismatic structure parting to moderate Slope: 2 to 8 percent medium subangular blocky; very hard, firm, Mean annual precipitation: 12 to 15 inches slightly sticky, moderately plastic; many very fine Composition roots; few fine pores; many faint clay films on faces of peds and in pores; neutral; gradual Major Components smooth boundary. Carfall and similar soils: 85 percent Bt2—15 to 20 inches; brown (10YR 5/3) sandy clay Minor Components loam, dark brown (10YR 3/3) moist; weak coarse Yamacall and similar soils: 0 to 4 percent prismatic structure parting to moderate medium Delpoint and similar soils: 0 to 4 percent subangular blocky; slightly hard, friable, slightly Busby and similar soils: 0 to 3 percent sticky, slightly plastic; many very fine roots; few Areas of blowouts: 0 to 2 percent fine pores; many faint clay films on faces of peds Soils with lighter colored surface layers: 0 to and in pores; neutral; gradual wavy boundary. 2 percent BC—20 to 30 inches; light brownish gray (2.5Y 6/2) sandy loam, grayish brown (10YR 4/2) moist; Major Component Description weak coarse subangular blocky structure; soft, Surface layer texture: Loam very friable, nonsticky, nonplastic; few very fine Depth class: Very deep (more than 60 inches) roots; few very fine pores; neutral, gradual wavy Drainage class: Well drained boundary. Dominant parent material: Alluvium C—30 to 60 inches; light yellowish brown (2.5Y 6/4) Native plant cover type: Rangeland sandy loam, light olive brown (2.5Y 5/4) moist; Flooding: None massive; soft, very friable, nonsticky, nonplastic; Available water capacity: Mainly 9.7 inches few very fine roots; neutral. Range in Characteristics A typical soil description with range in characteristics is included, in alphabetical order, Soil temperature: 42 to 47 degrees F in this section. Thickness of the mollic epipedon: 17 to 35 inches Management A horizon Hue: 10YR or 2.5Y For management information about this map unit, Value: 4 or 5 dry; 2 or 3 moist see appropriate sections in Part II of this publication. Chroma: 2 or 3 Texture: Loam or fine sandy loam Clay content: 10 to 25 percent 114C—Carfall-Assinniboine complex, Reaction: pH 6.1 to 7.3 2 to 8 percent slopes Bt horizons Hue: 10YR or 2.5Y Setting Value: 4, 5, or 6 dry; 3, 4, or 5 moist Landform: Chroma: 2 to 4 • Carfall—Sedimentary plains Texture: Sandy clay loam, clay loam, or loam • Assinniboine—Sedimentary plains Clay content: 20 to 35 percent Slope: Reaction: pH 6.1 to 7.3 • Carfall—2 to 8 percent BC and C horizons • Assinniboine—2 to 8 percent Hue: 10YR or 2.5Y Mean annual precipitation: 12 to 15 inches Value: 5 or 6 dry; 4 or 5 moist Composition Chroma: 2 to 4 Texture: Sandy loam or loamy sand Major Components Clay content: 10 to 20 percent Carfall and similar soils: 55 percent Reaction: pH 6.1 to 7.3 Assinniboine and similar soils: 30 percent Carter County, Montana—Part I 71

Minor Components Soils with lighter colored surface layers: 0 to Delpoint and similar soils: 0 to 5 percent 4 percent Busby and similar soils: 0 to 5 percent Soils that have slopes more than 15 percent: 0 to Soils with lighter colored surface layers: 0 to 3 percent 5 percent Major Component Description Major Component Description Carfall Carfall Surface layer texture: Loam Surface layer texture: Loam Depth class: Very deep (more than 60 inches) Depth class: Very deep (more than 60 inches) Drainage class: Well drained Drainage class: Well drained Dominant parent material: Alluvium Dominant parent material: Alluvium Native plant cover type: Rangeland Native plant cover type: Rangeland Flooding: None Flooding: None Available water capacity: Mainly 9.7 inches Available water capacity: Mainly 9.7 inches Assinniboine Assinniboine Surface layer texture: Sandy loam Surface layer texture: Sandy loam Depth class: Very deep (more than 60 inches) Depth class: Very deep (more than 60 inches) Drainage class: Well drained Drainage class: Well drained Dominant parent material: Alluvium Dominant parent material: Alluvium Native plant cover type: Rangeland Native plant cover type: Rangeland Flooding: None Flooding: None Available water capacity: Mainly 8.5 inches Available water capacity: Mainly 8.5 inches A typical soil description with range in A typical soil description with range in characteristics is included, in alphabetical order, characteristics is included, in alphabetical order, in this section. in this section. 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.

214C—Carfall fine sandy loam, 114D—Carfall-Assinniboine complex, 2 to 8 percent slopes 8 to 15 percent slopes Setting Setting Landform: Sedimentary plains Landform: Slope: 2 to 8 percent • Carfall—Hills Mean annual precipitation: 12 to 15 inches • Assinniboine—Hills Composition Slope: • Carfall—8 to 15 percent Major Components • Assinniboine—8 to 15 percent Carfall and similar soils: 85 percent Mean annual precipitation: 12 to 15 inches Minor Components Composition Soils that are calcareous throughout: 0 to 3 percent Carfall with loam surfaces: 0 to 3 percent Major Components Yamacall and similar soils: 0 to 3 percent Carfall and similar soils: 55 percent Delpoint and similar soils: 0 to 2 percent Assinniboine and similar soils: 30 percent Soils with lighter colored surface layers: 0 to Minor Components 2 percent Delpoint and similar soils: 0 to 4 percent Soils that have slopes more than 8 percent: 0 to Busby and similar soils: 0 to 4 percent 2 percent 72 Soil Survey

Major Component Description Chinook Series Surface layer texture: Fine sandy loam Depth class: Very deep (more than 60 inches) Depth class: Very deep (more than 60 inches) Drainage class: Well drained Drainage class: Well drained Permeability: Moderately rapid (2.0 to 6.0 inches/ Dominant parent material: Alluvium hour) Native plant cover type: Rangeland Landform: Alluvial fans and stream terraces Flooding: None Parent material: Alluvium Available water capacity: Mainly 8.8 inches Slope range: 0 to 15 percent Annual precipitation: 12 to 15 inches A typical soil description with range in characteristics is included, in alphabetical order, Taxonomic Class: Coarse-loamy, mixed Aridic in this section. Haploborolls Management Typical Pedon For management information about this map unit, see appropriate sections in Part II of this publication. Chinook sandy loam, 2 to 8 percent slopes, in an area of rangeland, 1,500 feet north and 1,600 feet east of the southwest corner of sec. 29, T. 3 S., 214D—Carfall fine sandy loam, R. 62 E. 8 to 15 percent slopes A—0 to 5 inches; grayish brown (10YR 5/2) sandy Setting loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure Landform: Hills parting to weak fine granular; slightly hard, very Slope: 8 to 15 percent friable, nonsticky, nonplastic; common very fine Mean annual precipitation: 12 to 15 inches and fine roots; few very fine and fine pores; Composition neutral; clear smooth boundary. Bw1—5 to 13 inches; grayish brown (10YR 5/2) Major Components sandy loam, very dark grayish brown (10YR 3/2) Carfall and similar soils: 85 percent moist; weak coarse prismatic structure parting to Minor Components moderate coarse subangular blocky; slightly hard, Yamacall and similar soils: 0 to 3 percent very friable, nonsticky, nonplastic; common very Delpoint and similar soils: 0 to 3 percent fine and fine roots; few very fine and fine pores; Busby and similar soils: 0 to 3 percent neutral; clear smooth boundary. Soils with lighter colored surface layers: 0 to Bw2—13 to 24 inches; grayish brown (2.5Y 5/2) 3 percent sandy loam; dark grayish brown (2.5Y 4/2) moist; Soils that have slopes more than 15 percent: 0 to weak coarse prismatic structure parting to weak 3 percent fine and medium subangular blocky; slightly hard, very friable, nonsticky, nonplastic; common very Major Component Description fine roots; few very fine pores; slightly alkaline; Surface layer texture: Fine sandy loam clear smooth boundary. Depth class: Very deep (more than 60 inches) Bk1—24 to 35 inches; light brownish gray (2.5Y 6/2) Drainage class: Well drained sandy loam, dark grayish brown (2.5Y 4/2) moist; Dominant parent material: Alluvium weak coarse subangular blocky structure; slightly Native plant cover type: Rangeland hard, very friable, nonsticky, nonplastic; few very Flooding: None fine and fine roots; few very fine pores; few fine Available water capacity: Mainly 8.8 inches masses of lime; strongly effervescent; slightly A typical soil description with range in alkaline; gradual smooth boundary. characteristics is included, in alphabetical order, Bk2—35 to 60 inches; light brownish gray (2.5Y 6/2) in this section. sandy loam, grayish brown (2.5Y 5/2) moist; weak coarse subangular blocky structure; slightly Management hard, very friable, nonsticky, nonplastic; common For management information about this map unit, fine masses of lime; violently effervescent; slightly see appropriate sections in Part II of this publication. alkaline. Carter County, Montana—Part I 73

Range in Characteristics Composition Soil temperature: 42 to 47 degrees F Major Components Thickness of the mollic epipedon: 7 to 15 inches Chinook and similar soils: 85 percent Depth to the Bk horizon: 12 to 35 inches Minor Components A horizon Assinniboine and similar soils: 0 to 3 percent Hue: 10YR or 2.5Y Eapa and similar soils: 0 to 3 percent Value: 2 or 3 moist Kremlin and similar soils: 0 to 3 percent Chroma: 2 or 3 Archin and similar soils: 0 to 3 percent Clay content: 5 to 18 percent Soils with gravelly surface layers: 0 to 2 percent Content of rock fragments: 0 to 35 percent Soils that have slopes more than 2 percent: 0 to pebbles 1 percent Reaction: pH 6.6 to 8.4 Major Component Description Bw horizons Surface layer texture: Sandy loam Hue: 10YR or 2.5Y Depth class: Very deep (more than 60 inches) Value: 4, 5, or 6 dry; 3, 4, or 5 moist Drainage class: Well drained Chroma: 2 to 4 Dominant parent material: Alluvium Texture: Fine sandy loam or sandy loam Native plant cover type: Rangeland Clay content: 5 to 18 percent Flooding: None Content of rock fragments: 0 to 15 percent Available water capacity: Mainly 8.1 inches pebbles Reaction: pH 6.6 to 8.4 A typical soil description with range in Bk1 horizon characteristics is included, in alphabetical order, Hue: 10YR, 2.5Y, or 5Y in this section. Value: 5, 6, or 7 dry; 4 or 5 moist Management Chroma: 2 to 4 Texture: Fine sandy loam or sandy loam For management information about this map unit, Clay content: 5 to 15 percent see appropriate sections in Part II of this publication. Content of rock fragments: 0 to 15 percent pebbles Calcium carbonate equivalent: 5 to 12 percent 83C—Chinook sandy loam, Reaction: pH 7.4 to 9.0 2 to 8 percent slopes Bk2 horizon Setting Hue: 10YR, 2.5Y, or 5Y Value: 5, 6, or 7 dry; 4, 5, or 6 moist Landform: Alluvial fans and stream terraces Chroma: 2 to 4 Slope: 2 to 8 percent Texture: Fine sandy loam or sandy loam Mean annual precipitation: 12 to 15 inches Clay content: 5 to 15 percent Composition Content of rock fragments: 0 to 15 percent pebbles Major Components Calcium carbonate equivalent: 5 to 15 percent Chinook and similar soils: 85 percent Reaction: pH 7.4 to 9.0 Minor Components Assinniboine and similar soils: 0 to 3 percent Busby and similar soils: 0 to 3 percent 83A—Chinook sandy loam, Eapa and similar soils: 0 to 3 percent 0 to 2 percent slopes Kremlin and similar soils: 0 to 3 percent Archin and similar soils: 0 to 2 percent Delpoint and similar soils: 0 to 1 percent Setting Major Component Description Landform: Alluvial fans and stream terraces Slope: 0 to 2 percent Surface layer texture: Sandy loam Mean annual precipitation: 12 to 15 inches Depth class: Very deep (more than 60 inches) 74 Soil Survey

Drainage class: Well drained 183C—Chinook-Assinniboine complex, Dominant parent material: Alluvium 2 to 8 percent slopes Native plant cover type: Rangeland Flooding: None Available water capacity: Mainly 8.1 inches Setting Landform: A typical soil description with range in • Chinook—Alluvial fans and stream terraces characteristics is included, in alphabetical order, • Assinniboine—Alluvial fans and stream terraces in this section. Position on landform: Management • Chinook—Backslopes and footslopes • Assinniboine—Backslopes and footslopes For management information about this map unit, Slope: see appropriate sections in Part II of this publication. • Chinook—2 to 8 percent • Assinniboine—2 to 8 percent 83D—Chinook sandy loam, Mean annual precipitation: 12 to 15 inches 8 to 15 percent slopes Composition Major Components Setting Chinook and similar soils: 45 percent Landform: Alluvial fans and stream terraces Assinniboine and similar soils: 40 percent Slope: 8 to 15 percent Minor Components Mean annual precipitation: 12 to 15 inches Archin and similar soils: 0 to 3 percent Composition Eapa and similar soils: 0 to 3 percent Marmarth and similar soils: 0 to 3 percent Major Components Soils with gravelly surface layers: 0 to 3 percent Chinook and similar soils: 85 percent Areas of blowouts: 0 to 2 percent Minor Components Soils that have slopes more than 8 percent: 0 to Busby and similar soils: 0 to 3 percent 1 percent Twilight and similar soils: 0 to 3 percent Major Component Description Soils with gravelly surface layers: 0 to 3 percent Delpoint and similar soils: 0 to 3 percent Chinook Areas of blowouts: 0 to 2 percent Surface layer texture: Sandy loam Soils with lighter colored surface layers: 0 to Depth class: Very deep (more than 60 inches) 1 percent Drainage class: Well drained Dominant parent material: Alluvium Major Component Description Native plant cover type: Rangeland Surface layer texture: Sandy loam Flooding: None Depth class: Very deep (more than 60 inches) Available water capacity: Mainly 8.1 inches Drainage class: Well drained Dominant parent material: Alluvium Assinniboine Native plant cover type: Rangeland Surface layer texture: Sandy clay loam Flooding: None Depth class: Very deep (more than 60 inches) Available water capacity: Mainly 8.1 inches Drainage class: Well drained Dominant parent material: Alluvium A typical soil description with range in Native plant cover type: Rangeland characteristics is included, in alphabetical order, Flooding: None in this section. Available water capacity: Mainly 8.6 inches Management A typical soil description with range in For management information about this map unit, characteristics is included, in alphabetical order, see appropriate sections in Part II of this publication. in this section. Carter County, Montana—Part I 75

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.

283C—Chinook-Archin complex, Cohagen Series 2 to 8 percent slopes Depth class: Shallow (10 to 20 inches) Drainage class: Well drained Setting Permeability: Moderately rapid (2.0 to 6.0 inches/ hour) Landform: Landform: Sedimentary plains and hills • Chinook—Alluvial fans and stream terraces Parent material: Soft sandstone bedrock • Archin—Alluvial fans and stream terraces Slope range: 4 to 15 percent Slope: Annual precipitation: 15 to 17 inches • Chinook—2 to 8 percent • Archin—2 to 8 percent Taxonomic Class: Loamy, mixed (calcareous), frigid, Mean annual precipitation: 12 to 15 inches shallow Typic Ustorthents Composition Typical Pedon Major Components Cohagen fine sandy loam, in an area of Parshall- Chinook and similar soils: 45 percent Cohagen fine sandy loams, 4 to 15 percent slopes, Archin and similar soils: 40 percent in an area of rangeland, 2,000 feet south and Minor Components 2,300 feet east of the northwest corner of sec. 29, Busby and similar soils: 0 to 3 percent T. 2 N., R. 62 E. Twilight and similar soils: 0 to 3 percent A—0 to 3 inches; brown (10YR 5/3) fine sandy loam, Delpoint and similar soils: 0 to 3 percent dark brown (10YR 3/3) moist; weak coarse Areas of slickspots: 0 to 3 percent subangular blocky structure; slightly hard, very Soils with slopes more than 8 percent: 0 to 3 percent friable, nonsticky, nonplastic; few fine and many Major Component Description very fine roots; few very fine pores; slightly alkaline; abrupt wavy boundary. Chinook C—3 to 12 inches; light brownish gray (10YR 6/2) fine Surface layer texture: Sandy loam sandy loam, dark grayish brown (10YR 4/2) Depth class: Very deep (more than 60 inches) moist; weak medium subangular blocky structure; Drainage class: Well drained slightly hard, very friable, nonsticky, nonplastic; Dominant parent material: Alluvium many very fine roots; 30 percent soft sandstone Native plant cover type: Rangeland fragments; disseminated lime; violently Flooding: None effervescent; slightly alkaline; clear wavy Available water capacity: Mainly 8.1 inches boundary. Cr—12 to 60 inches; light gray (10YR 7/2) soft Archin sandstone bedrock that crushes to fine sandy Surface layer texture: Fine sandy loam loam, grayish brown (10YR 5/2) moist. Depth class: Very deep (more than 60 inches) Drainage class: Well drained Range in Characteristics Dominant parent material: Alluvium Depth to the Cr horizon: 10 to 20 inches Native plant cover type: Rangeland Flooding: None A horizon Salt affected: Saline within 30 inches Hue: 10YR or 2.5Y Sodium affected: Sodic within 30 inches Value: 4, 5, or 6 dry; 3 or 4 moist Available water capacity: Mainly 6.6 inches Chroma: 2 to 4 Clay content: 10 to 18 percent A typical soil description with range in Content of rock fragments: 0 to 15 percent soft characteristics is included, in alphabetical order, sandstone fragments in this section. Reaction: pH 7.4 to 8.4 76 Soil Survey

C horizon moist; moderate medium subangular blocky Hue: 10YR or 2.5Y structure; hard, very firm, sticky and plastic; Value: 5, 6, or 7 dry; 4 or 5 moist common very fine roots; common very fine Chroma: 2 to 4 tubular pores; common fine masses of lime; Texture: Fine sandy loam or sandy loam violently effervescent; strongly alkaline; gradual Clay content: 10 to 18 percent wavy boundary. Content of rock fragments: 0 to 50 percent soft Bky—30 to 60 inches; light brownish gray (2.5Y 6/2) sandstone fragments silty clay loam, dark grayish brown (2.5Y 4/2) Calcium carbonate equivalent: 1 to 5 percent moist; moderate medium subangular blocky Reaction: pH 7.4 to 8.4 structure; hard, very firm, sticky and plastic; few very fine roots; few very fine pores; many fine nests and seams of gypsum crystals; many fine Creed Series and medium masses of lime; strongly effervescent; strongly alkaline. Depth class: Very deep (more than 60 inches) Drainage class: Well drained Range in Characteristics Permeability: Slow (0.06 to 0.2 inch/hour) Landform: Alluvial fans and stream terraces Soil temperature: 42 to 47 degrees F Parent material: Alluvium Depth to the Bkn horizon: 16 to 20 inches Slope range: 0 to 8 percent Depth to the Bky horizon: 25 to 30 inches Annual precipitation: 12 to 15 inches Soil phase: Warm Taxonomic note: Map unit 602C is a taxadjunct to Taxonomic Class: Fine, montmorillonitic Typic the Creed series in order to join soils that have Natriboralfs an average soil temperature greater than 47 degrees F. Typical Pedon A horizon Creed loam, in an area of Creed-Absher complex, Hue: 10YR, 2.5Y, or 5Y 2 to 8 percent slopes, in an area of rangeland, Value: 5 or 6 dry; 4 or 5 moist 1,000 feet south and 1,700 feet west of the northeast Chroma: 2 or 3 corner of sec. 8, T. 3 N., R. 56 E. Clay content: 20 to 27 percent A—0 to 5 inches; pale brown (10YR 6/3) loam, brown Content of rock fragments: 0 to 15 percent (10YR 4/3) moist; strong thin platy structure pebbles parting to strong very fine and fine granular; soft, Reaction: pH 6.1 to 8.4 very friable, nonsticky, slightly plastic; few fine E horizon and many very fine roots; common very fine and Hue: 10YR, 2.5Y, or 5Y fine pores; neutral; clear smooth boundary. Value: 5, 6, or 7 dry; 4, 5, 6, or 7 moist E—5 to 8 inches; light brownish gray (10YR 6/2) Chroma: 2 or 3 loam, dark grayish brown (10YR 4/2) moist; Clay content: 20 to 27 percent moderate medium subangular blocky structure Content of rock fragments: 0 to 15 percent parting to moderate thin platy; slightly hard, very pebbles friable, nonsticky, slightly plastic; few fine and Reaction: pH 6.1 to 8.4 many very fine roots; few fine and many very fine pores; neutral; abrupt smooth boundary. Btn horizon Btn—8 to 17 inches; light brownish gray (2.5Y 6/2) Hue: 10YR, 2.5Y, or 5Y clay loam, dark grayish brown (2.5Y 4/2) moist; Value: 4, 5, or 6 dry; 3, 4, or 5 moist moderate medium and coarse columnar structure Chroma: 2 or 3 parting to moderate medium subangular blocky; Texture: Clay loam, silty clay loam, clay, or silty very hard, firm, very sticky, very plastic; common clay very fine roots; many very fine tubular pores; Clay content: 35 to 55 percent many distinct clay films on faces of peds, Content of rock fragments: 0 to 15 percent continuous prominent clay films in pores; slightly pebbles alkaline; clear smooth boundary. Electrical conductivity: 2 to 8 mmhos/cm Bkn—17 to 30 inches; light brownish gray (2.5Y 6/2) Sodium adsorption ratio: 8 to 20 silty clay loam, dark grayish brown (2.5Y 4/2) Reaction: pH 6.6 to 9.0 Carter County, Montana—Part I 77

Bkn horizon Native plant cover type: Rangeland Hue: 10YR, 2.5Y, or 5Y Flooding: None Value: 4, 5, 6, or 7 dry; 4, 5, or 6 moist Salt affected: Saline within 30 inches Chroma: 2 to 4 Sodium affected: Sodic within 30 inches Texture: Silty clay loam, clay loam, sandy clay Available water capacity: Mainly 6.7 inches loam, loam, or clay Content of rock fragments: 0 to 15 percent A typical soil description with range in pebbles characteristics is included, in alphabetical order, Clay content: 27 to 45 percent in this section. Calcium carbonate equivalent: 5 to 15 percent Management Electrical conductivity: 4 to 8 mmhos/cm Sodium adsorption ratio: 13 to 20 For management information about this map unit, Gypsum content: 0 to 2 percent see appropriate sections in Part II of this publication. Reaction: pH 7.9 to 9.0 Bky horizon Hue: 10YR, 2.5Y, or 5Y 54C—Creed loam, 2 to 8 percent slopes Value: 5 or 6 dry; 4 or 5 moist Chroma: 2 to 4 Setting Texture: Loam, clay loam, sandy clay loam, or Landform: Alluvial fans and stream terraces silty clay loam Slope: 2 to 8 percent Clay content: 25 to 35 percent Mean annual precipitation: 12 to 15 inches Calcium carbonate equivalent: 5 to 10 percent Content of rock fragments: 0 to 15 percent Composition pebbles Major Components Electrical conductivity: 4 to 16 mmhos/cm Creed and similar soils: 85 percent Sodium adsorption ratio: 13 to 25 Gypsum content: 1 to 5 percent Minor Components Reaction: pH 7.9 to 9.0 Absher and similar soils: 0 to 4 percent Gerdrum and similar soils: 0 to 4 percent Archin and similar soils: 0 to 3 percent 54A—Creed loam, 0 to 2 percent slopes Areas of slickspots: 0 to 2 percent Soils with darker colored surface layers: 0 to Setting 1 percent Soils that have slopes less than 2 percent: 0 to Landform: Alluvial fans and stream terraces 1 percent Slope: 0 to 2 percent Mean annual precipitation: 12 to 15 inches Major Component Description Composition Surface layer texture: Loam Depth class: Very deep (more than 60 inches) Major Components Drainage class: Well drained Creed and similar soils: 85 percent Dominant parent material: Alluvium Minor Components Native plant cover type: Rangeland Absher and similar soils: 0 to 4 percent Flooding: None Gerdrum and similar soils: 0 to 4 percent Salt affected: Saline within 30 inches Soils with darker colored surface layers: 0 to Sodium affected: Sodic within 30 inches 3 percent Available water capacity: Mainly 6.7 inches Archin and similar soils: 0 to 2 percent Areas of slickspots: 0 to 2 percent A typical soil description with range in characteristics is included, in alphabetical order, Major Component Description in this section. Surface layer texture: Loam Management Depth class: Very deep (more than 60 inches) Drainage class: Well drained For management information about this map unit, Dominant parent material: Alluvium see appropriate sections in Part II of this publication. 78 Soil Survey

154C—Creed-Absher complex, Management 2 to 8 percent slopes For management information about this map unit, see appropriate sections in Part II of this publication. Setting Landform: • Creed—Alluvial fans and stream terraces 254C—Creed-Gerdrum complex, • Absher—Alluvial fans and stream terraces 2 to 8 percent slopes Position on landform: • Creed—Microhighs Setting • Absher—Microlows Slope: Landform: • Creed—2 to 8 percent • Creed—Alluvial fans and stream terraces • Absher—2 to 8 percent • Gerdrum—Alluvial fans and stream terraces Mean annual precipitation: 12 to 15 inches Position on landform: • Creed—Microhighs Composition • Gerdrum—Microlows Major Components Slope: Creed and similar soils: 55 percent • Creed—2 to 8 percent Absher and similar soils: 30 percent • Gerdrum—2 to 8 percent Mean annual precipitation: 12 to 15 inches Minor Components Gerdrum and similar soils: 0 to 4 percent Composition Archin and similar soils: 0 to 4 percent Major Components Very deep nonsaline soils: 0 to 3 percent Creed and similar soils: 45 percent Areas of slickspots: 0 to 3 percent Gerdrum and similar soils: 40 percent Soils with darker colored surface layers: 0 to 1 percent Minor Components Absher and similar soils: 0 to 4 percent Major Component Description Yamacall and similar soils: 0 to 4 percent Creed Kobase and similar soils: 0 to 4 percent Surface layer texture: Loam Areas of slickspots: 0 to 3 percent Depth class: Very deep (more than 60 inches) Major Component Description Drainage class: Well drained Dominant parent material: Alluvium Creed Native plant cover type: Rangeland Surface layer texture: Loam Flooding: None Depth class: Very deep (more than 60 inches) Salt affected: Saline within 30 inches Drainage class: Well drained Sodium affected: Sodic within 30 inches Dominant parent material: Alluvium Available water capacity: Mainly 6.7 inches Native plant cover type: Rangeland Flooding: None Absher Salt affected: Saline within 30 inches Surface layer texture: Clay Sodium affected: Sodic within 30 inches Depth class: Very deep (more than 60 inches) Available water capacity: Mainly 6.7 inches Drainage class: Moderately well drained Dominant parent material: Alluvium Gerdrum Native plant cover type: Rangeland Surface layer texture: Clay loam Flooding: None Depth class: Very deep (more than 60 inches) Salt affected: Saline within 30 inches Drainage class: Well drained Sodium affected: Sodic within 30 inches Dominant parent material: Alluvium Available water capacity: Mainly 4.1 inches Native plant cover type: Rangeland Flooding: None A typical soil description with range in Salt affected: Saline within 30 inches characteristics is included, in alphabetical order, Sodium affected: Sodic within 30 inches in this section. Available water capacity: Mainly 6.1 inches Carter County, Montana—Part I 79

A typical soil description with range in Salt affected: Saline within 30 inches characteristics is included, in alphabetical order, Sodium affected: Sodic within 30 inches in this section. Available water capacity: Mainly 6.1 inches Management A typical soil description with range in For management information about this map unit, characteristics is included, in alphabetical order, see appropriate sections in Part II of this publication. in this section. Management 602C—Creed-Gerdrum complex, warm, For management information about this map unit, 2 to 6 percent slopes see appropriate sections in Part II of this publication.

Setting Daglum Series Landform: • Creed—Alluvial fans and stream terraces Depth class: Very deep (more than 60 inches) • Gerdrum—Alluvial fans and stream terraces Drainage class: Well drained Position on landform: Permeability: Slow (0.06 to 0.2 inch/hour) • Creed—Microhighs Landform: Alluvial fans and stream terraces • Gerdrum—Microlows Parent material: Alluvium Slope: Slope range: 0 to 4 percent • Creed—2 to 6 percent Annual precipitation: 12 to 15 inches • Gerdrum—2 to 6 percent Mean annual precipitation: 12 to 15 inches Taxonomic Class: Fine, montmorillonitic Vertic Natriborolls Composition Major Components Typical Pedon Creed and similar soils: 45 percent Gerdrum and similar soils: 40 percent Daglum loam, 0 to 4 percent slopes, in an area of rangeland, 2,600 feet south and 800 feet west of the Minor Components northeast corner of sec. 11, T. 4 S., R. 60 E. Absher and similar soils: 0 to 4 percent Kobase and similar soils: 0 to 4 percent A—0 to 6 inches; grayish brown (10YR 5/2) loam, Yamacall and similar soils: 0 to 4 percent very dark grayish brown (10YR 3/2) moist; weak Areas of slickspots: 0 to 3 percent fine and medium subangular blocky structure; slightly hard, friable, slightly sticky, slightly plastic; Major Component Description few fine and many very fine roots; few fine and Creed common very fine pores; slightly acid; clear Surface layer texture: Loam smooth boundary. Depth class: Very deep (more than 60 inches) E—6 to 9 inches; grayish brown (10YR 5/2) loam, Drainage class: Well drained very dark grayish brown (10YR 3/2) moist; weak Dominant parent material: Alluvium thin platy structure parting to moderate fine and Native plant cover type: Rangeland medium subangular blocky; slightly hard, very Flooding: None friable, slightly sticky, slightly plastic; few fine and Salt affected: Saline within 30 inches many very fine roots; few very fine and fine pores; Sodium affected: Sodic within 30 inches neutral; abrupt smooth boundary. Available water capacity: Mainly 6.7 inches Btn1—9 to 13 inches; brown (10YR 5/3) clay, dark grayish brown (10YR 4/2) moist; moderate Gerdrum medium and coarse columnar structure parting to Surface layer texture: Clay loam strong fine and medium subangular blocky; Depth class: Very deep (more than 60 inches) extremely hard, very firm, very sticky, very plastic; Drainage class: Well drained common very fine roots; few very fine and fine Dominant parent material: Alluvium pores; continuous distinct clay films on faces of Native plant cover type: Rangeland peds, continuous prominent clay films in pores; Flooding: None moderately alkaline; gradual wavy boundary. 80 Soil Survey

Btn2—13 to 21 inches; pale brown (10YR 6/3) clay, Electrical conductivity: 8 to 16 mmhos/cm brown (10YR 5/3) moist; moderate medium Sodium adsorption ratio: 13 to 20 subangular blocky structure; very hard, very firm, Reaction: pH 7.4 to 9.0 very sticky, very plastic; common very fine roots; few very fine pores; common distinct clay films on faces of peds, continuous distinct clay films in 45B—Daglum loam, 0 to 4 percent slopes pores; moderately alkaline; gradual wavy boundary. Setting Bky—21 to 60 inches; light brownish gray (2.5Y 6/2) Landform: Alluvial fans and stream terraces silty clay loam, dark grayish brown (2.5Y 4/2) Slope: 0 to 4 percent moist; moderate coarse subangular blocky Mean annual precipitation: 12 to 15 inches structure; very hard, firm, very sticky, moderately plastic; few very fine roots; few very fine pores; Composition common fine seams and nests of gypsum Major Components crystals; common fine masses of lime; violently Daglum and similar soils: 85 percent effervescent; strongly alkaline. Minor Components Range in Characteristics Absher and similar soils: 0 to 3 percent Areas of slickspots: 0 to 3 percent Soil temperature: 42 to 47 degrees F Marvan and similar soils: 0 to 3 percent Thickness of the mollic epipedon: 7 to 15 inches Soils with lighter colored surface layers: 0 to Taxonomic note: Daglum soil, as used in Carter 2 percent County, is a taxadjunct to the series. It classifies Soils that have slopes more than 4 percent: 0 to as Fine, montmorillonitic Aridic Natriborolls. Use 2 percent and management is similar. Somewhat poorly drained soils: 0 to 2 percent A horizon Major Component Description Value: 3, 4, or 5 dry; 2 or 3 moist Clay content: 18 to 26 percent Surface layer texture: Loam Reaction: pH 5.6 to 7.3 Depth class: Very deep (more than 60 inches) Drainage class: Well drained E horizon Dominant parent material: Alluvium Hue: 10YR or 2.5Y Native plant cover type: Rangeland Value: 4, 5, 6, or 7 dry; 3, 4, or 5 moist Flooding: None Chroma: 1 or 2 Salt affected: Saline within 30 inches Clay content: 18 to 26 percent Sodium affected: Sodic within 30 inches Reaction: pH 5.6 to 7.3 Available water capacity: Mainly 7.9 inches Btn horizons Hue: 10YR or 2.5Y A typical soil description with range in Value: 3, 4, 5, or 6 dry; 2, 3, 4, or 5 moist characteristics is included, in alphabetical order, Chroma: 2 or 3 in this section. Texture: Clay, silty clay, silty clay loam, or clay Management loam Clay content: 35 to 60 percent For management information about this map unit, Electrical conductivity: 2 to 8 mmhos/cm see appropriate sections in Part II of this publication. Sodium adsorption ratio: 10 to 20 Reaction: pH 6.1 to 9.0 Dast Series Bky horizon Hue: 2.5Y or 5Y Depth class: Moderately deep (20 to 40 inches) Value: 5, 6, or 7 dry; 3, 4, 5, or 6 moist Drainage class: Well drained Chroma: 1 to 4 Permeability: Moderately rapid (2.0 to 6.0 inches/ Texture: Clay loam, silty clay, silty clay loam, or hour) clay Landform: Sedimentary plains and hills Clay content: 35 to 60 percent Parent material: Semiconsolidated, sandy Calcium carbonate equivalent: 5 to 15 percent sedimentary beds Carter County, Montana—Part I 81

Slope range: 4 to 60 percent Content of rock fragments: 0 to 15 percent Annual precipitation: 15 to 17 inches pebbles Reaction: pH 7.4 to 8.4 Taxonomic Class: Coarse-loamy, mixed frigid Typic Bk horizon Ustochrepts Hue: 10YR, 2.5Y, or 5Y Typical Pedon Value: 5, 6, or 7 dry; 4, 5, or 6 moist Chroma: 2 to 4 Dast sandy loam, in an area of Dast-Ridge-Rock Texture: Fine sandy loam, sandy loam, or loam outcrop complex, 35 to 60 percent slopes, in an area Clay content: 2 to 18 percent of forestland, 200 feet south and 1,400 feet east of Content of rock fragments: 0 to 15 percent the northwest corner of sec. 17, T. 3 S., R. 62 E. pebbles Oi—1 inch to 0; slightly decomposed forest litter. Calcium carbonate equivalent: 5 to 15 percent A—0 to 5 inches; light brownish gray (10YR 6/2) Reaction: pH 7.4 to 8.4 sandy loam, dark grayish brown (10YR 4/2) moist; weak fine granular structure; soft, very friable, nonsticky, nonplastic; many very fine 125F—Dast-Ridge-Rock outcrop complex, roots; slightly alkaline; clear smooth boundary. 35 to 60 percent slopes Bw—5 to 13 inches; light brownish gray (2.5Y 6/2) sandy loam, dark grayish brown (2.5Y 4/2) moist; Setting weak coarse prismatic structure; soft, very friable, Landform: nonsticky, nonplastic; many very fine roots; few • Dast—Hills very fine pores; slightly alkaline; gradual wavy • Ridge—Hills boundary. • Rock outcrop—Hills Bk—13 to 28 inches; light gray (2.5Y 7/2) sandy Position on landform: loam, grayish brown (2.5Y 5/2) moist; weak • Dast—Backslopes coarse prismatic structure; soft, very friable, • Ridge—Summits nonsticky, nonplastic; common very fine roots; • Rock outcrop—Shoulders and summits few fine pores; 30 percent soft channers; few fine Slope: masses of lime; violently effervescent; moderately • Dast—35 to 60 percent alkaline; gradual wavy boundary. • Ridge—35 to 60 percent Cr—28 to 60 inches; white (2.5Y 8/2) Mean annual precipitation: 15 to 17 inches semiconsolidated, sandy sedimentary beds that crush to fine sandy loam; light gray (2.5Y 7/2) Composition moist. Major Components Range in Characteristics Dast and similar soils: 30 percent Ridge and similar soils: 30 percent Soil temperature: 42 to 47 degrees F Rock outcrop: 25 percent Depth to the Bk horizon: 13 to 24 inches Depth to bedrock: 20 to 40 inches Minor Components Moderately deep loamy soils: 0 to 4 percent A horizon Soils with darker colored surface layers: 0 to Hue: 10YR or 2.5Y 4 percent Value: 4, 5, or 6 dry; 4 or 5 moist Soils that have slopes less than 35 percent: 0 to Chroma: 2 to 4 4 percent Clay content: 2 to 18 percent Soils with flagstones: 0 to 3 percent Content of rock fragments: 0 to 15 percent pebbles Major Component Description Reaction: pH 7.4 to 8.4 Dast Bw horizon Surface layer texture: Sandy loam Hue: 10YR, 2.5Y, or 5Y Depth class: Moderately deep (20 to 40 inches) Value: 5 or 6 dry; 4 or 5 moist Drainage class: Well drained Chroma: 2 to 4 Dominant parent material: Semiconsolidated, sandy Texture: Fine sandy loam, sandy loam, or loam sedimentary beds Clay content: 2 to 18 percent Native plant cover type: Forestland 82 Soil Survey

Flooding: None Major Component Description Available water capacity: Mainly 3.6 inches Dast Surface layer texture: Sandy loam Ridge Depth class: Moderately deep (20 to 40 inches) Surface layer texture: Sandy loam Drainage class: Well drained Depth class: Shallow (10 to 20 inches) Dominant parent material: Semiconsolidated, sandy Drainage class: Well drained sedimentary beds Dominant parent material: Semiconsolidated, sandy Native plant cover type: Forestland sedimentary beds Flooding: None Native plant cover type: Forestland Available water capacity: Mainly 3.6 inches Flooding: None Available water capacity: Mainly 2.2 inches Vebar Surface layer texture: Fine sandy loam Rock outcrop Depth class: Moderately deep (20 to 40 inches) Definition: Consolidated sandstone Drainage class: Well drained Dominant parent material: Semiconsolidated, sandy A typical soil description with range in sedimentary beds characteristics is included, in alphabetical order, Native plant cover type: Forestland in this section. Flooding: None Management Available water capacity: Mainly 3.4 inches For management information about this map unit, A typical soil description with range in see appropriate sections in Part II of this publication. characteristics is included, in alphabetical order, in this section. 225E—Dast-Vebar complex, Management 15 to 35 percent slopes For management information about this map unit, see appropriate sections in Part II of this publication. Setting Landform: 225F—Dast-Vebar complex, • Dast—Hills 35 to 60 percent slopes • Vebar—Hills Slope: Setting • Dast—15 to 35 percent Landform: • Vebar—15 to 35 percent • Dast—Hills Mean annual precipitation: 15 to 17 inches • Vebar—Hills Slope: Composition • Dast—35 to 60 percent Major Components • Vebar—35 to 50 percent Dast and similar soils: 50 percent Mean annual precipitation: 15 to 17 inches Vebar and similar soils: 35 percent Composition Minor Components Major Components Cabba and similar soils: 0 to 4 percent Dast and similar soils: 50 percent Noncalcareous soils: 0 to 4 percent Vebar and similar soils: 35 percent Areas of rock outcrop: 0 to 3 percent Sandy textured soils: 0 to 3 percent Minor Components Soils with darker colored surface layers: 0 to Shallow sandy soils: 0 to 4 percent 1 percent Shallow loamy soils: 0 to 4 percent Carter County, Montana—Part I 83

Noncalcareous soils: 0 to 3 percent Composition Areas of rock outcrop: 0 to 2 percent Major Components Soils that have slopes less than 35 percent: 0 to Dast and similar soils: 35 percent 2 percent Cabba and similar soils: 30 percent Major Component Description Mowbray and similar soils: 20 percent Dast Minor Components Surface layer texture: Sandy loam Very shallow loamy soils: 0 to 4 percent Depth class: Moderately deep (20 to 40 inches) Soils with darker colored surface layers: 0 to Drainage class: Well drained 3 percent Dominant parent material: Semiconsolidated, sandy Soils that have slopes less than 15 percent: 0 to sedimentary beds 3 percent Native plant cover type: Forestland Soils that have slopes more than 35 percent: 0 to Flooding: None 3 percent Available water capacity: Mainly 3.6 inches Areas of rock outcrop: 0 to 2 percent Major Component Description Vebar Surface layer texture: Fine sandy loam Dast Depth class: Moderately deep (20 to 40 inches) Surface layer texture: Sandy loam Drainage class: Well drained Depth class: Moderately deep (20 to 40 inches) Dominant parent material: Semiconsolidated, sandy Drainage class: Well drained sedimentary beds Dominant parent material: Semiconsolidated, sandy Native plant cover type: Forestland sedimentary beds Flooding: None Native plant cover type: Forestland Available water capacity: Mainly 3.4 inches Flooding: None Available water capacity: Mainly 3.6 inches A typical soil description with range in characteristics is included, in alphabetical order, Cabba in this section. Surface layer texture: Very stony loam Depth class: Shallow (10 to 20 inches) Management Drainage class: Well drained Dominant parent material: Semiconsolidated, loamy For management information about this map unit, sedimentary beds see appropriate sections in Part II of this publication. Native plant cover type: Rangeland Flooding: None 325E—Dast-Cabba-Mowbray complex, Available water capacity: Mainly 2.2 inches 15 to 35 percent slopes Mowbray Surface layer texture: Very channery loam Setting Depth class: Very deep (more than 60 inches) Landform: Drainage class: Well drained • Dast—Hills Dominant parent material: Colluvium • Cabba—Hills Native plant cover type: Forestland • Mowbray—Hills Flooding: None Slope: Available water capacity: Mainly 4.4 inches • Dast—15 to 35 percent, north aspect • Cabba—15 to 35 percent, south aspect A typical soil description with range in • Mowbray—15 to 35 percent, north aspect characteristics is included, in alphabetical order, Mean annual precipitation: 15 to 17 inches in this section. 84 Soil Survey

Management Other features: In areas that are cultivated, slight to strong effervescence may result from mixing the For management information about this map unit, A and Bw horizons. see appropriate sections in Part II of this publication. A horizon Hue: 10YR or 2.5Y Delpoint Series Value: 5 or 6 dry; 3, 4, or 5 moist Chroma: 2 to 4 Depth class: Moderately deep (20 to 40 inches) Clay content: 20 to 27 percent Drainage class: Well drained Content of rock fragments: 0 to 5 percent pebbles Permeability: Moderate (0.6 to 2.0 inches/hour) Reaction: pH 6.6 to 8.4 Landform: Sedimentary plains and hills Parent material: Semiconsolidated, loamy Bw horizon sedimentary beds Hue: 10YR, 2.5Y, or 5Y Slope range: 2 to 25 percent Value: 5, 6, or 7 dry; 4 or 5 moist Annual precipitation: 12 to 15 inches Chroma: 2 to 4 Texture: Loam, clay loam, or silty clay loam Taxonomic Class: Fine-loamy, mixed, frigid Aridic Clay content: 18 to 35 percent Ustochrepts Content of rock fragments: 0 to 15 percent pebbles Typical Pedon Reaction: pH 7.4 to 8.4 Delpoint loam, in an area of Delpoint-Cabbart Bk horizon complex, 8 to 15 percent slopes, in an area of Hue: 10YR, 2.5Y, or 5Y rangeland, 1,700 feet south and 900 feet west of Value: 5, 6, or 7 dry; 4, 5, or 6 moist the northeast corner of sec. 16, T. 6 S., R. 59 E. Chroma: 2 to 4 A—0 to 5 inches; grayish brown (10YR 5/2) loam, Texture: Loam, sandy loam, clay loam, or silty dark grayish brown (10YR 4/2) moist; moderate clay loam fine and medium granular structure; slightly hard, Clay content: 18 to 35 percent friable, slightly sticky, slightly plastic; many very Content of rock fragments: 0 to 15 percent fine and fine roots; many very fine pores; slightly pebbles alkaline; clear wavy boundary. Calcium carbonate equivalent: 5 to 15 percent Bw—5 to 19 inches; light brownish gray (10YR 6/2) Reaction: pH 7.9 to 9.0 loam, grayish brown (10YR 5/2) moist; weak medium prismatic structure parting to moderate fine and medium subangular blocky; hard, friable, 71C—Delpoint loam, 2 to 8 percent slopes slightly sticky, moderately plastic; many very fine and fine roots; many very fine pores; Setting disseminated lime; strongly effervescent; Landform: Sedimentary plains moderately alkaline; clear wavy boundary. Slope: 2 to 8 percent Bk—19 to 29 inches; pale brown (10YR 6/3) silty clay Mean annual precipitation: 12 to 15 inches loam, brown (10YR 5/3) moist; moderate fine subangular blocky structure; hard, friable, Composition moderately sticky, moderately plastic; common Major Components very fine and fine roots; few fine and common Delpoint and similar soils: 85 percent very fine pores; common fine and medium masses of lime; violently effervescent; moderately Minor Components alkaline; gradual smooth boundary. Cabbart and similar soils: 0 to 4 percent Cr—29 to 60 inches; very pale brown (10YR 7/3) Yamacall and similar soils: 0 to 3 percent semiconsolidated, loamy sedimentary beds that Kremlin and similar soils: 0 to 3 percent crush to loam, pale brown (10YR 6/3) moist. Soils that are calcareous throughout: 0 to 3 percent Archin and similar soils: 0 to 2 percent Range in Characteristics Major Component Description Soil temperature: 42 to 47 degrees F Depth to the Bk horizon: 10 to 20 inches Surface layer texture: Loam Depth to the Cr horizon: 20 to 40 inches Depth class: Moderately deep (20 to 40 inches) Carter County, Montana—Part I 85

Drainage class: Well drained Flooding: None Dominant parent material: Semiconsolidated, loamy Available water capacity: Mainly 4.7 inches sedimentary beds Native plant cover type: Rangeland Cabbart Flooding: None Surface layer texture: Silt loam Available water capacity: Mainly 4.7 inches Depth class: Shallow (10 to 20 inches) Drainage class: Well drained A typical soil description with range in Dominant parent material: Semiconsolidated, loamy characteristics is included, in alphabetical order, sedimentary beds in this section. Native plant cover type: Rangeland Flooding: None Management Available water capacity: Mainly 2.2 inches For management information about this map unit, see appropriate sections in Part II of this publication. A typical soil description with range in characteristics is included, in alphabetical order, in this section. 171C—Delpoint-Cabbart complex, Management 2 to 8 percent slopes For management information about this map unit, see appropriate sections in Part II of this publication. Setting Landform: 171D—Delpoint-Cabbart complex, • Delpoint—Sedimentary plains 8 to 15 percent slopes • Cabbart—Sedimentary plains Position on landform: Setting • Delpoint—Backslopes • Cabbart—Shoulders and summits Landform: Slope: • Delpoint—Hills • Delpoint—2 to 8 percent • Cabbart—Hills • Cabbart—2 to 8 percent Position on landform: Mean annual precipitation: 12 to 15 inches • Delpoint—Backslopes • Cabbart—Shoulders and summits Composition Slope: Major Components • Delpoint—8 to 15 percent Delpoint and similar soils: 60 percent • Cabbart—8 to 15 percent Cabbart and similar soils: 30 percent Mean annual precipitation: 12 to 15 inches Minor Components Composition Yamacall and similar soils: 0 to 2 percent Major Components Kremlin and similar soils: 0 to 2 percent Delpoint and similar soils: 50 percent Marmarth and similar soils: 0 to 2 percent Cabbart and similar soils: 35 percent Archin and similar soils: 0 to 2 percent Very shallow loamy soils: 0 to 1 percent Minor Components Soils that have slopes more than 8 percent: 0 to Yamacall and similar soils: 0 to 3 percent 1 percent Cambeth and similar soils: 0 to 3 percent Blacksheep and similar soils: 0 to 3 percent Major Component Description Very shallow loamy soils: 0 to 3 percent Delpoint Soils that have slopes more than 15 percent: 0 to Surface layer texture: Loam 3 percent Depth class: Moderately deep (20 to 40 inches) Major Component Description Drainage class: Well drained Dominant parent material: Semiconsolidated, loamy Delpoint sedimentary beds Surface layer texture: Loam Native plant cover type: Rangeland Depth class: Moderately deep (20 to 40 inches) 86 Soil Survey

Drainage class: Well drained Major Component Description Dominant parent material: Semiconsolidated, loamy Delpoint sedimentary beds Surface layer texture: Loam Native plant cover type: Rangeland Depth class: Moderately deep (20 to 40 inches) Flooding: None Drainage class: Well drained Available water capacity: Mainly 4.7 inches Dominant parent material: Semiconsolidated, loamy sedimentary beds Cabbart Native plant cover type: Rangeland Surface layer texture: Silt loam Flooding: None Depth class: Shallow (10 to 20 inches) Available water capacity: Mainly 4.7 inches Drainage class: Well drained Dominant parent material: Semiconsolidated, loamy Yamacall sedimentary beds Surface layer texture: Loam Native plant cover type: Rangeland Depth class: Very deep (more than 60 inches) Flooding: None Drainage class: Well drained Available water capacity: Mainly 2.2 inches Dominant parent material: Alluvium Native plant cover type: Rangeland A typical soil description with range in Flooding: None characteristics is included, in alphabetical order, Available water capacity: Mainly 9.7 inches in this section. Management A typical soil description with range in characteristics is included, in alphabetical order, For management information about this map unit, in this section. see appropriate sections in Part II of this publication. Management 271D—Delpoint-Yamacall loams, For management information about this map unit, 8 to 15 percent slopes see appropriate sections in Part II of this publication.

Setting DA—Denied access Landform: • Delpoint—Hills Composition • Yamacall—Hills Major Components Position on landform: Denied access: 100 percent • Delpoint—Backslopes and shoulders • Yamacall—Footslopes and toeslopes Major Component Description Slope: Definition: Areas where soil mapping access was • Delpoint—8 to 15 percent denied by the landowner • Yamacall—8 to 15 percent Mean annual precipitation: 12 to 15 inches Composition Eapa Series Major Components Depth class: Very deep (more than 60 inches) Delpoint and similar soils: 50 percent Drainage class: Well drained Yamacall and similar soils: 35 percent Permeability: Moderate (0.6 to 2.0 inches/hour) Minor Components Landform: Alluvial fans and stream terraces Cabbart and similar soils: 0 to 4 percent Parent material: Alluvium Cambeth and similar soils: 0 to 4 percent Slope range: 0 to 15 percent Very shallow loamy soils: 0 to 3 percent Annual precipitation: 12 to 15 inches Soils that are calcareous throughout: 0 to 3 percent Soils that have slopes more than 15 percent: 0 to Taxonomic Class: Fine-loamy, mixed Aridic 1 percent Argiborolls Carter County, Montana—Part I 87

Typical Pedon Chroma: 2 to 4 Texture: Loam or clay loam Eapa loam, 0 to 2 percent slopes, in an area of Clay content: 24 to 34 percent cropland, 300 feet north and 300 feet east of the Reaction: pH 6.1 to 7.8 southwest corner of sec. 16, T. 3 S., R. 61 E. Bk horizon Ap—0 to 8 inches; grayish brown (10YR 5/2) loam, Hue: 10YR, 2.5Y, or 5Y very dark grayish brown (10YR 3/2) moist; Value: 5, 6, or 7 dry; 4 or 5 moist moderate fine subangular blocky structure; Chroma: 1 to 4 slightly hard, friable, slightly sticky, slightly plastic; Texture: Loam, clay loam, or sandy clay loam many very fine roots; common very fine pores; Clay content: 18 to 30 percent neutral; abrupt smooth boundary. Calcium carbonate equivalent: 5 to 15 percent Bt1—8 to 13 inches; brown (10YR 5/3) clay loam, Reaction: pH 7.4 to 8.4 brown (10YR 4/3) moist; moderate medium prismatic structure parting to strong fine and medium subangular blocky; very hard, friable, moderately sticky, moderately plastic; few fine 84A—Eapa loam, 0 to 2 percent slopes and many very fine roots; many very fine pores; common faint clay films on faces of peds and in Setting pores; neutral; gradual wavy boundary. Landform: Alluvial fans and stream terraces Bt2—13 to 24 inches; pale brown (10YR 6/3) clay Slope: 0 to 2 percent loam, brown (10YR 4/3) moist; moderate medium Mean annual precipitation: 12 to 15 inches prismatic structure parting to strong medium subangular blocky; extremely hard, firm, very Composition sticky, very plastic; common very fine roots; few Major Components very fine pores; common faint clay films on faces Eapa and similar soils: 85 percent of peds and in pores; slightly alkaline; gradual wavy boundary. Minor Components Bk—24 to 60 inches; very pale brown (10YR 7/3) Ethridge and similar soils: 0 to 3 percent loam, brown (10YR 5/3) moist; moderate medium Kremlin and similar soils: 0 to 3 percent subangular blocky structure; hard, friable, very Soils with lighter colored surface layers: 0 to sticky, moderately plastic; few very fine roots; few 3 percent very fine tubular pores; many fine and medium Archin and similar soils: 0 to 3 percent masses of lime; strongly effervescent; moderately Soils that have slopes more than 2 percent: 0 to alkaline. 2 percent Areas of slickspots: 0 to 1 percent Range in Characteristics Major Component Description Thickness of the mollic epipedon: 7 to 16 inches Depth to the Bk horizon: 15 to 30 inches Surface layer texture: Loam Soil phases: Warm Depth class: Very deep (more than 60 inches) Taxonomic note: Map unit 603C is a taxadjunct to the Drainage class: Well drained Eapa series because the average soil Dominant parent material: Alluvium temperature is greater than 47 degrees F. Native plant cover type: Rangeland Flooding: None Ap horizon Available water capacity: Mainly 11.1 inches Hue: 10YR or 2.5Y Value: 4 or 5 dry; 2 or 3 moist A typical soil description with range in Chroma: 1 or 2 characteristics is included, in alphabetical order, Clay content: 20 to 30 percent in this section. Reaction: pH 6.1 to 7.8 Management Bt horizons Hue: 10YR or 2.5Y For management information about this map unit, Value: 4, 5, or 6 dry; 3 or 4 moist see appropriate sections in Part II of this publication. 88 Soil Survey

84C—Eapa loam, 2 to 8 percent slopes Cambeth and similar soils: 0 to 3 percent Soils that have slopes less than 8 percent: 0 to 3 percent Setting Major Component Description Landform: Alluvial fans and stream terraces Slope: 2 to 8 percent Surface layer texture: Loam Mean annual precipitation: 12 to 15 inches Depth class: Very deep (more than 60 inches) Drainage class: Well drained Composition Dominant parent material: Alluvium Major Components Native plant cover type: Rangeland Eapa and similar soils: 85 percent Flooding: None Available water capacity: Mainly 11.1 inches Minor Components Ethridge and similar soils: 0 to 3 percent A typical soil description with range in Kremlin and similar soils: 0 to 3 percent characteristics is included, in alphabetical order, Archin and similar soils: 0 to 3 percent in this section. Soils with lighter colored surface layers: 0 to 3 percent Management Areas of slickspots: 0 to 3 percent For management information about this map unit, Major Component Description see appropriate sections in Part II of this publication. Surface layer texture: Loam Depth class: Very deep (more than 60 inches) 167C—Eapa-Yamacall loams, Drainage class: Well drained 2 to 8 percent slopes Dominant parent material: Alluvium Native plant cover type: Rangeland Setting Flooding: None Available water capacity: Mainly 11.1 inches Landform: • Eapa—Alluvial fans and stream terraces A typical soil description with range in • Yamacall—Alluvial fans and stream terraces characteristics is included, in alphabetical order, Slope: in this section. • Eapa—2 to 8 percent • Yamacall—2 to 8 percent Management Mean annual precipitation: 12 to 15 inches For management information about this map unit, Composition see appropriate sections in Part II of this publication. Major Components Eapa and similar soils: 45 percent 84D—Eapa loam, 8 to 15 percent slopes Yamacall and similar soils: 40 percent Minor Components Setting Cambeth and similar soils: 0 to 4 percent Delpoint and similar soils: 0 to 4 percent Landform: Alluvial fans and stream terraces Marmarth and similar soils: 0 to 3 percent Slope: 8 to 15 percent Archin and similar soils: 0 to 3 percent Mean annual precipitation: 12 to 15 inches Soils that have slopes more than 8 percent: 0 to Composition 1 percent Major Components Major Component Description Eapa and similar soils: 85 percent Eapa Minor Components Surface layer texture: Loam Kremlin and similar soils: 0 to 3 percent Depth class: Very deep (more than 60 inches) Marmarth and similar soils: 0 to 3 percent Drainage class: Well drained Soils with lighter colored surface layers: 0 to Dominant parent material: Alluvium 3 percent Native plant cover type: Rangeland Carter County, Montana—Part I 89

Flooding: None Native plant cover type: Rangeland Available water capacity: Mainly 11.1 inches Flooding: None Available water capacity: Mainly 11.1 inches Yamacall Surface layer texture: Loam Archin Depth class: Very deep (more than 60 inches) Surface layer texture: Loam Drainage class: Well drained Depth class: Very deep (more than 60 inches) Dominant parent material: Alluvium Drainage class: Well drained Native plant cover type: Rangeland Dominant parent material: Alluvium Flooding: None Native plant cover type: Rangeland Available water capacity: Mainly 9.7 inches Flooding: None Salt affected: Saline within 30 inches A typical soil description with range in Sodium affected: Sodic within 30 inches characteristics is included, in alphabetical order, Available water capacity: Mainly 7.0 inches in this section. A typical soil description with range in Management characteristics is included, in alphabetical order, For management information about this map unit, in this section. see appropriate sections in Part II of this publication. Management For management information about this map unit, 184C—Eapa-Archin loams, see appropriate sections in Part II of this publication. 2 to 8 percent slopes

Setting 603C—Eapa loam, warm, Landform: 1 to 6 percent slopes • Eapa—Alluvial fans • Archin—Alluvial fans Setting Slope: • Eapa—2 to 8 percent Landform: Alluvial fans and stream terraces • Archin—2 to 8 percent Slope: 1 to 6 percent Mean annual precipitation: 12 to 15 inches Mean annual precipitation: 12 to 15 inches Composition Composition Major Components Major Components Eapa and similar soils: 45 percent Eapa and similar soils: 85 percent Archin and similar soils: 40 percent Minor Components Minor Components Archin and similar soils: 0 to 3 percent Cambeth and similar soils: 0 to 4 percent Busby and similar soils: 0 to 3 percent Busby and similar soils: 0 to 4 percent Cambeth and similar soils: 0 to 3 percent Soils with darker colored surface layers: 0 to Soils that have slopes more than 6 percent: 0 to 3 percent 3 percent Marmarth and similar soils: 0 to 2 percent Areas of slickspots: 0 to 3 percent Soils that have slopes less than 2 percent: 0 to Major Component Description 2 percent Surface layer texture: Loam Major Component Description Depth class: Very deep (more than 60 inches) Eapa Drainage class: Well drained Surface layer texture: Loam Dominant parent material: Alluvium Depth class: Very deep (more than 60 inches) Native plant cover type: Rangeland Drainage class: Well drained Flooding: None Dominant parent material: Alluvium Available water capacity: Mainly 11.1 inches 90 Soil Survey

A typical soil description with range in moderately plastic; few very fine roots; few very characteristics is included, in alphabetical order, fine pores; common fine masses of lime; strongly in this section. effervescent; moderately alkaline; clear wavy boundary. Management Bky—29 to 60 inches; light olive brown (2.5Y 5/4) clay loam, grayish brown (2.5Y 4/4) moist; weak For management information about this map unit, coarse subangular blocky structure; hard, firm, see appropriate sections in Part II of this publication. moderately sticky, slightly plastic; few very fine roots; few very fine pores; few very fine masses, Ethridge Series common threads and seams of lime; few fine seams of gypsum; violently effervescent; strongly Depth class: Very deep (more than 60 inches) alkaline. Drainage class: Well drained Permeability: Slow (0.06 to 0.2 inch/hour) Range in Characteristics Landform: Alluvial fans and stream terraces Soil temperature: 42 to 47 degrees F Parent material: Alluvium Thickness of the mollic epipedon: 7 to 14 inches Slope range: 0 to 15 percent Taxonomic note: Map unit 626C is a taxadjunct to Annual precipitation: 12 to 15 inches the Ethridge series in order to join soils that have an average soil temperature greater than Taxonomic Class: Fine, montmorillonitic Aridic 47 degrees F. Argiborolls A horizon Typical Pedon Hue: 10YR or 2.5Y Ethridge loam, 2 to 8 percent slopes, in an area of Value: 2 or 3 moist rangeland, 2,300 feet south and 2,500 feet east of Chroma: 2 or 3 the northwest corner of sec. 24, T. 6 S., R. 55 E. Texture: Loam or silty clay loam Clay content: 20 to 35 percent A—0 to 6 inches; grayish brown (10YR 5/2) loam, Content of rock fragments: 0 to 5 percent pebbles very dark grayish brown (10YR 3/2) moist; weak Reaction: pH 6.1 to 7.8 medium subangular blocky structure parting to moderate medium granular; slightly hard, friable, Bt horizons slightly sticky, slightly plastic; few fine and coarse Hue: 10YR or 2.5Y and common very fine roots; many very fine Value: 3 or 4 moist pores; slightly acid; clear wavy boundary. Chroma: 2 to 4 Bt1—6 to 14 inches; grayish brown (2.5Y 5/2) clay, Texture: Clay, silty clay, clay loam, or silty clay dark grayish brown (2.5Y 4/2) moist; moderate loam medium subangular blocky structure parting to Clay content: 35 to 45 percent moderate fine angular blocky; hard, firm, Content of rock fragments: 0 to 5 percent pebbles moderately sticky, moderately plastic; common Reaction: pH 6.6 to 8.4 very fine and fine roots; common very fine pores; Bk horizon continuous distinct clay films on faces of peds, Hue: 10YR or 2.5Y continuous prominent clay films in pores; neutral; Value: 5, 6, or 7 dry; 4, 5, or 6 moist clear wavy boundary. Chroma: 2 to 4 Bt2—14 to 24 inches; grayish brown (2.5Y 5/2) clay, Texture: Silty clay loam, loam, or clay loam dark grayish brown (2.5Y 4/2) moist; moderate Clay content: 25 to 40 percent medium prismatic structure parting to moderate Content of rock fragments: 0 to 5 percent pebbles fine subangular blocky; very hard, firm, very Calcium carbonate equivalent: 5 to 15 percent sticky, moderately plastic; common very fine Reaction: pH 7.4 to 9.0 roots; few very fine pores; common faint clay films on faces of peds, common distinct clay films in Bky horizon pores; neutral; clear wavy boundary. Hue: 10YR or 2.5Y Bk—24 to 29 inches; light brownish gray (2.5Y 6/2) Value: 5, 6, or 7 dry; 4, 5, or 6 moist clay loam, grayish brown (2.5Y 5/2) moist; Chroma: 2 to 4 moderate fine and medium subangular blocky Texture: Clay loam, silt loam, loam, or silty clay structure; hard, firm, moderately sticky, loam Carter County, Montana—Part I 91

Clay content: 25 to 40 percent Composition Content of rock fragments: 0 to 5 percent pebbles Major Components Electrical conductivity: 2 to 4 mmhos/cm Ethridge and similar soils: 85 percent Sodium adsorption ratio: 1 to 5 Calcium carbonate equivalent: 5 to 15 percent Minor Components Gypsum content: 1 to 3 percent Eapa and similar soils: 0 to 4 percent Reaction: pH 7.4 to 9.0 Marias and similar soils: 0 to 4 percent Archin and similar soils: 0 to 3 percent Soils with silty clay loam surfaces: 0 to 3 percent 66C—Ethridge silty clay loam, Soils that have slopes more than 2 percent: 0 to 2 to 8 percent slopes 1 percent Major Component Description Setting Surface layer texture: Loam Depth class: Very deep (more than 60 inches) Landform: Alluvial fans and stream terraces Drainage class: Well drained Slope: 2 to 8 percent Dominant parent material: Alluvium Mean annual precipitation: 12 to 15 inches Native plant cover type: Rangeland Composition Flooding: None Available water capacity: Mainly 9.8 inches Major Components Ethridge and similar soils: 85 percent A typical soil description with range in Minor Components characteristics is included, in alphabetical order, Eapa and similar soils: 0 to 4 percent in this section. Archin and similar soils: 0 to 4 percent Management Weingart and similar soils: 0 to 3 percent Delpoint and similar soils: 0 to 2 percent For management information about this map unit, Soils that have darker colored surface layers: 0 to see appropriate sections in Part II of this publication. 2 percent Major Component Description 85C—Ethridge loam, 2 to 8 percent slopes Surface layer texture: Silty clay loam Depth class: Very deep (more than 60 inches) Setting Drainage class: Well drained Dominant parent material: Alluvium Landform: Alluvial fans and stream terraces Native plant cover type: Rangeland Slope: 2 to 8 percent Flooding: None Mean annual precipitation: 12 to 15 inches Available water capacity: Mainly 9.9 inches Composition A typical soil description with range in Major Components characteristics is included, in alphabetical order, Ethridge and similar soils: 85 percent in this section. Minor Components Management Eapa and similar soils: 0 to 3 percent Marias and similar soils: 0 to 3 percent For management information about this map unit, Archin and similar soils: 0 to 3 percent see appropriate sections in Part II of this publication. Soils with silty clay loam surfaces: 0 to 3 percent Soils that have slopes more than 8 percent: 0 to 85A—Ethridge loam, 0 to 2 percent slopes 3 percent Major Component Description Setting Surface layer texture: Loam Landform: Alluvial fans and stream terraces Depth class: Very deep (more than 60 inches) Slope: 0 to 2 percent Drainage class: Well drained Mean annual precipitation: 12 to 15 inches Dominant parent material: Alluvium 92 Soil Survey

Native plant cover type: Rangeland Drainage class: Well drained Flooding: None Dominant parent material: Alluvium Available water capacity: Mainly 9.8 inches Native plant cover type: Rangeland Flooding: None A typical soil description with range in Salt affected: Saline within 30 inches characteristics is included, in alphabetical order, Sodium affected: Sodic within 30 inches in this section. Available water capacity: Mainly 7.9 inches Management A typical soil description with range in For management information about this map unit, characteristics is included, in alphabetical order, see appropriate sections in Part II of this publication. in this section. Management 185A—Ethridge-Daglum complex, For management information about this map unit, 0 to 4 percent slopes see appropriate sections in Part II of this publication.

Setting 626C—Ethridge silty clay loam, warm, Landform: 2 to 8 percent slopes • Ethridge—Alluvial fans and stream terraces • Daglum—Alluvial fans and stream terraces Setting Slope: • Ethridge—0 to 4 percent Landform: Alluvial fans and stream terraces • Daglum—0 to 4 percent Slope: 2 to 8 percent Mean annual precipitation: 12 to 15 inches Mean annual precipitation: 12 to 15 inches Composition Composition Major Components Major Components Ethridge and similar soils: 50 percent Ethridge and similar soils: 85 percent Daglum and similar soils: 35 percent Minor Components Minor Components Eapa and similar soils: 0 to 4 percent Eapa and similar soils: 0 to 3 percent Weingart and similar soils: 0 to 4 percent Weingart and similar soils: 0 to 3 percent Archin and similar soils: 0 to 3 percent Absher and similar soils: 0 to 3 percent Delpoint and similar soils: 0 to 2 percent Soils with lighter colored surface layers: 0 to Soils with darker colored surface layers: 0 to 2 percent 2 percent Soils that have slopes more than 4 percent: 0 to Major Component Description 2 percent Areas of slickspots: 0 to 2 percent Surface layer texture: Silty clay loam Depth class: Very deep (more than 60 inches) Major Component Description Drainage class: Well drained Ethridge Dominant parent material: Alluvium Surface layer texture: Loam Native plant cover type: Rangeland Depth class: Very deep (more than 60 inches) Flooding: None Drainage class: Well drained Available water capacity: Mainly 9.9 inches Dominant parent material: Alluvium Native plant cover type: Rangeland A typical soil description with range in Flooding: None characteristics is included, in alphabetical order, Available water capacity: Mainly 9.8 inches in this section. Management Daglum Surface layer texture: Loam For management information about this map unit, Depth class: Very deep (more than 60 inches) see appropriate sections in Part II of this publication. Carter County, Montana—Part I 93

Gerdrum Series few very fine pores; common fine nests and seams of gypsum crystals; few fine seams and Depth class: Very deep (more than 60 inches) threads of other salts; many fine masses of lime; Drainage class: Well drained strongly effervescent; strongly alkaline; gradual Permeability: Very slow (less than 0.06 inch/hour) wavy boundary. Landform: Alluvial fans and stream terraces Bknyz2—38 to 60 inches; light brownish gray (10YR Parent material: Alluvium 6/2) clay, grayish brown (10YR 5/2) moist; Slope range: 0 to 9 percent massive; hard, firm, very sticky, very plastic; few Annual precipitation: 12 to 15 inches very fine roots; common fine nests and seams of gypsum crystals; few fine seams and threads of Taxonomic Class: Fine, montmorillonitic Typic other salts; many fine masses of lime; strongly Natriboralfs effervescent; strongly alkaline. Typical Pedon Range in Characteristics Gerdrum clay loam, 2 to 8 percent slopes, in an area Soil temperature: 42 to 47 degrees F of rangeland, 1,800 feet north and 1,000 feet east of Depth to the Btkn horizon: 10 to 24 inches the southwest corner of sec. 12, T. 3 N., R. 55 E. Soil phases: Warm Taxonomic note: Map units 602C, 611B, and 611D A—0 to 2 inches; light brownish gray (10YR 6/2) are taxadjuncts to the Gerdrum series in order to loam, dark grayish brown (10YR 4/2) moist; join soils that have an average soil temperature moderate medium granular structure; soft, very greater than 47 degrees F. friable, slightly sticky, slightly plastic; few fine and many very fine roots; slightly alkaline; clear A horizon smooth boundary. Hue: 10YR or 2.5Y E—2 to 4 inches; light brownish gray (10YR 6/2) Value: 5, 6, or 7 dry; 4 or 5 moist loam, dark grayish brown (10YR 4/2) moist; Chroma: 2 or 3 strong thin platy structure parting to strong fine Texture: Clay loam when mixed to 7 inches granular; slightly hard, friable, slightly sticky, Clay content: 10 to 25 percent slightly plastic; few fine and many very fine roots; Content of rock fragments: 0 to 15 percent common very fine and fine pores; slightly pebbles alkaline; abrupt smooth boundary. Reaction: pH 6.6 to 7.8 Btn—4 to 14 inches; grayish brown (10YR 5/2) clay, E horizon dark grayish brown (10YR 4/2) moist; strong Hue: 10YR or 2.5Y medium columnar structure parting to strong Value: 6 or 7 dry; 4, 5, or 6 moist medium and coarse subangular blocky; extremely Chroma: 2 or 3 hard, firm, very sticky, very plastic; few fine and Clay content: 10 to 25 percent many very fine roots; few fine and common very Content of rock fragments: 0 to 15 percent fine pores; continuous distinct clay films on faces pebbles of peds and in pores; strongly alkaline; clear Reaction: pH 6.6 to 7.8 smooth boundary. Btkn—14 to 26 inches; light brownish gray (10YR 6/2) Btn horizon clay, dark grayish brown (10YR 4/2) moist; Hue: 10YR or 2.5Y moderate medium prismatic structure parting to Value: 5, 6, or 7 dry; 4 or 5 moist strong medium subangular blocky; slightly hard, Chroma: 2 to 4 firm, moderately sticky, moderately plastic; few Texture: Clay, silty clay, or silty clay loam fine and common very fine roots; few very fine Clay content: 35 to 55 percent and fine pores; many faint clay films on faces of Content of rock fragments: 0 to 10 percent peds, many distinct clay films in pores; few fine pebbles masses of lime; strongly effervescent; strongly Electrical conductivity: 2 to 8 mmhos/cm alkaline; gradual wavy boundary. Sodium adsorption ratio: 10 to 20; pedons with Bknyz1—26 to 38 inches; light brownish gray (10YR sodium adsorption ratio of less than 13 have 6/2) clay, dark grayish brown (10YR 4/2) moist; more exchangeable magnesium plus sodium weak coarse subangular blocky structure; hard, than calcium plus exchange acidity at pH 8.2. firm, very sticky, very plastic; few very fine roots; Reaction: pH 7.4 to 9.0 94 Soil Survey

Btkn horizon Dominant parent material: Alluvium Hue: 10YR, 2.5Y, or 5Y Native plant cover type: Rangeland Value: 5, 6, or 7 dry; 4, 5, or 6 moist Flooding: None Chroma: 2 or 3 Salt affected: Saline within 30 inches Texture: Clay, silty clay, silty clay loam, or clay Sodium affected: Sodic within 30 inches loam Available water capacity: Mainly 6.1 inches Clay content: 30 to 50 percent Content of rock fragments: 0 to 10 percent A typical soil description with range in pebbles characteristics is included, in alphabetical order, Calcium carbonate equivalent: 5 to 15 percent in this section. Electrical conductivity: 8 to 16 mmhos/cm Management Sodium adsorption ratio: 13 to 20 Reaction: pH 7.9 to 9.0 For management information about this map unit, see appropriate sections in Part II of this publication. Bknyz horizons Hue: 10YR, 2.5Y, or 5Y Value: 4, 5, 6, or 7 dry; 4, 5, or 6 moist Chroma: 2 to 4 65C—Gerdrum clay loam, Textures: Clay loam, sandy clay loam, clay, or 2 to 8 percent slopes silty clay Clay content: 10 to 50 percent Setting Content of rock fragments: 0 to 10 percent Landform: Alluvial fans and stream terraces pebbles Slope: 2 to 8 percent Calcium carbonate equivalent: 5 to 15 percent Mean annual precipitation: 12 to 15 inches Electrical conductivity: 8 to 16 mmhos/cm Sodium adsorption ratio: 13 to 20 Composition Gypsum content: 1 to 5 percent Major Components Reaction: pH 7.9 to 9.0 Gerdrum and similar soils: 85 percent Minor Components 65A—Gerdrum clay loam, Absher and similar soils: 0 to 3 percent 0 to 2 percent slopes Creed and similar soils: 0 to 3 percent Weingart and similar soils: 0 to 3 percent Kobase and similar soils: 0 to 3 percent Setting Areas of slickspots: 0 to 3 percent Landform: Alluvial fans and stream terraces Major Component Description Slope: 0 to 2 percent Surface layer texture: Clay loam Mean annual precipitation: 12 to 15 inches Depth class: Very deep (more than 60 inches) Composition Drainage class: Well drained Dominant parent material: Alluvium Major Components Native plant cover type: Rangeland Gerdrum and similar soils: 85 percent Flooding: None Minor Components Salt affected: Saline within 30 inches Absher and similar soils: 0 to 4 percent Sodium affected: Sodic within 30 inches Weingart and similar soils: 0 to 3 percent Available water capacity: Mainly 6.1 inches Creed and similar soils: 0 to 3 percent Kobase and similar soils: 0 to 3 percent A typical soil description with range in Areas of slickspots: 0 to 2 percent characteristics is included, in alphabetical order, in this section. Major Component Description Management Surface layer texture: Clay loam Depth class: Very deep (more than 60 inches) For management information about this map unit, Drainage class: Well drained see appropriate sections in Part II of this publication. Carter County, Montana—Part I 95

165A—Gerdrum-Absher complex, Management 0 to 2 percent slopes For management information about this map unit, see appropriate sections in Part II of this publication. Setting Landform: 165C—Gerdrum-Absher complex, • Gerdrum—Alluvial fans and stream terraces 2 to 8 percent slopes • Absher—Alluvial fans and stream terraces Position on landform: Setting • Gerdrum—Microhighs Landform: • Absher—Microlows • Gerdrum—Alluvial fans and stream terraces Slope: • Absher—Alluvial fans and stream terraces • Gerdrum—0 to 2 percent Position on landform: • Absher—0 to 2 percent • Gerdrum—Microhighs Mean annual precipitation: 12 to 15 inches • Absher—Microlows Composition Slope: • Gerdrum—2 to 8 percent Major Components • Absher—2 to 8 percent Gerdrum and similar soils: 60 percent Mean annual precipitation: 12 to 15 inches Absher and similar soils: 30 percent Composition Minor Components Weingart and similar soils: 0 to 3 percent Major Components Creed and similar soils: 0 to 3 percent Gerdrum and similar soils: 60 percent Marvan and similar soils: 0 to 2 percent Absher and similar soils: 30 percent Kobase and similar soils: 0 to 2 percent Minor Components Weingart and similar soils: 0 to 3 percent Major Component Description Creed and similar soils: 0 to 3 percent Gerdrum Marvan and similar soils: 0 to 2 percent Surface layer texture: Clay loam Kobase and similar soils: 0 to 2 percent Depth class: Very deep (more than 60 inches) Major Component Description Drainage class: Well drained Dominant parent material: Alluvium Gerdrum Native plant cover type: Rangeland Surface layer texture: Clay loam Flooding: None Depth class: Very deep (more than 60 inches) Salt affected: Saline within 30 inches Drainage class: Well drained Sodium affected: Sodic within 30 inches Dominant parent material: Alluvium Available water capacity: Mainly 6.1 inches Native plant cover type: Rangeland Flooding: None Absher Salt affected: Saline within 30 inches Surface layer texture: Clay Sodium affected: Sodic within 30 inches Depth class: Very deep (more than 60 inches) Available water capacity: Mainly 6.1 inches Drainage class: Moderately well drained Dominant parent material: Alluvium Absher Native plant cover type: Rangeland Surface layer texture: Clay Flooding: None Depth class: Very deep (more than 60 inches) Salt affected: Saline within 30 inches Drainage class: Moderately well drained Sodium affected: Sodic within 30 inches Dominant parent material: Alluvium Available water capacity: Mainly 4.1 inches Native plant cover type: Rangeland Flooding: None A typical soil description with range in Salt affected: Saline within 30 inches characteristics is included, in alphabetical order, Sodium affected: Sodic within 30 inches in this section. Available water capacity: Mainly 4.1 inches 96 Soil Survey

A typical soil description with range in Salt affected: Saline within 30 inches characteristics is included, in alphabetical order, Sodium affected: Sodic within 30 inches in this section. Available water capacity: Mainly 4.1 inches Management A typical soil description with range in For management information about this map unit, characteristics is included, in alphabetical order, see appropriate sections in Part II of this publication. in this section. Management 611B—Gerdrum-Absher complex, warm, For management information about this map unit, 0 to 3 percent slopes see appropriate sections in Part II of this publication.

Setting 611D—Gerdrum-Absher complex, warm, Landform: 3 to 9 percent slopes • Gerdrum—Alluvial fans and stream terraces • Absher—Alluvial fans and stream terraces Setting Position on landform: • Gerdrum—Microhighs Landform: • Absher—Microlows • Gerdrum—Alluvial fans and stream terraces Slope: • Absher—Alluvial fans and stream terraces • Gerdrum—0 to 3 percent Position on landform: • Absher—0 to 3 percent • Gerdrum—Microhighs Mean annual precipitation: 12 to 15 inches • Absher—Microlows Slope: Composition • Gerdrum—3 to 9 percent Major Components • Absher—3 to 9 percent Gerdrum and similar soils: 60 percent Mean annual precipitation: 12 to 15 inches Absher and similar soils: 30 percent Composition Minor Components Major Components Weingart and similar soils: 0 to 3 percent Gerdrum and similar soils: 60 percent Creed and similar soils: 0 to 3 percent Absher and similar soils: 30 percent Marvan and similar soils: 0 to 2 percent Kobase and similar soils: 0 to 2 percent Minor Components Weingart and similar soils: 0 to 3 percent Major Component Description Creed and similar soils: 0 to 3 percent Gerdrum Marvan and similar soils: 0 to 2 percent Surface layer texture: Clay loam Kobase and similar soils: 0 to 2 percent Depth class: Very deep (more than 60 inches) Major Component Description Drainage class: Well drained Dominant parent material: Alluvium Gerdrum Native plant cover type: Rangeland Surface layer texture: Clay loam Flooding: None Depth class: Very deep (more than 60 inches) Salt affected: Saline within 30 inches Drainage class: Well drained Sodium affected: Sodic within 30 inches Dominant parent material: Alluvium Available water capacity: Mainly 6.1 inches Native plant cover type: Rangeland Flooding: None Absher Salt affected: Saline within 30 inches Surface layer texture: Clay Sodium affected: Sodic within 30 inches Depth class: Very deep (more than 60 inches) Available water capacity: Mainly 6.1 inches Drainage class: Moderately well drained Dominant parent material: Alluvium Absher Native plant cover type: Rangeland Surface layer texture: Clay Flooding: None Depth class: Very deep (more than 60 inches) Carter County, Montana—Part I 97

Drainage class: Moderately well drained nonplastic; few very fine and fine roots; few thin Dominant parent material: Alluvium strata of loamy sand; disseminated lime; strongly Native plant cover type: Rangeland effervescent; slightly alkaline; gradual wavy Flooding: None boundary. Salt affected: Saline within 30 inches C3—36 to 60 inches; light brownish gray (10YR 6/2) Sodium affected: Sodic within 30 inches stratified fine sandy loam and loamy fine sand, Available water capacity: Mainly 4.1 inches dark grayish brown (10YR 4/2) moist; massive; soft, very friable, nonsticky, nonplastic; A typical soil description with range in disseminated lime; strongly effervescent; slightly characteristics is included, in alphabetical order, alkaline. in this section. Range in Characteristics Management Soil temperature: 42 to 47 degrees F For management information about this map unit, Soil phases: Saline see appropriate sections in Part II of this publication. A horizon Hue: 10YR, 2.5Y, or 5Y Value: 4, 5, or 6 dry; 3, 4, or 5 moist Glendive Series Chroma: 2 or 3 Clay content: 5 to 15 percent Depth class: Very deep (more than 60 inches) Electrical conductivity: 0 to 2 mmhos/cm; saline Drainage class: Well drained or moderately well phase: 4 to 8 mmhos/cm drained Sodium adsorption ratio: 0 to 5; saline phase: Permeability: Moderately rapid (2.0 to 6.0 inches/ 13 to 70 hour) Calcium carbonate equivalent: 0 to 5 percent Landform: Flood plains Reaction: pH 6.6 to 9.0 Parent material: Alluvium Slope range: 0 to 4 percent C1 and C2 horizons Annual precipitation: 12 to 15 inches Hue: 10YR, 2.5Y, or 5Y Value: 5, 6, or 7 dry; 4, 5, or 6 moist Taxonomic Class: Coarse-loamy, mixed Chroma: 2 to 4 (calcareous), frigid Aridic Ustifluvents Texture: Loam, silt loam, sandy loam, or fine sandy loam Typical Pedon Clay content: 5 to 18 percent Glendive sandy loam, 0 to 2 percent slopes, in an Content of rock fragments: 0 to 15 percent area of rangeland, 1,850 feet south and 100 feet west pebbles of the northeast corner of sec. 36, T. 3 S., R. 61 E. Electrical conductivity: 0 to 4 mmhos/cm; saline phase: 8 to 16 mmhos/cm A—0 to 4 inches; grayish brown (10YR 5/2) sandy Sodium adsorption ratio: 0 to 5; saline phase: loam, very dark grayish brown (10YR 3/2) moist; 13 to 70 weak thin platy structure parting to weak fine Reaction: pH 7.4 to 9.0 granular; soft, very friable, nonsticky, nonplastic; common very fine roots; few fine and common C3 horizon very fine pores; slightly alkaline; gradual smooth Hue: 10YR, 2.5Y, or 5Y boundary. Value: 5, 6, or 7 dry; 4, 5, or 6 moist C1—4 to 18 inches; light brownish gray (10YR 6/2) Chroma: 2 to 4 fine sandy loam, dark grayish brown (10YR 4/2) Texture: Sandy loam or fine sandy loam moist; weak coarse subangular blocky structure; consisting of thin layers of loam, sandy loam, soft, very friable, nonsticky, nonplastic; few fine silt loam, loamy sand, loamy fine sand, and and common very fine roots; few very fine and occasionally clay loam fine pores; slightly alkaline; gradual wavy Clay content: 5 to 18 percent boundary. Content of rock fragments: 0 to 15 percent C2—18 to 36 inches; light brownish gray (10YR 6/2) pebbles fine sandy loam, dark grayish brown (10YR 4/2) Electrical conductivity: 0 to 4 mmhos/cm; saline moist; massive; soft, very friable, nonsticky, phase: 8 to 32 mmhos/cm 98 Soil Survey

Sodium adsorption ratio: 0 to 5; saline phase: Minor Components 13 to 70 Havre and similar soils: 0 to 4 percent Reaction: pH 7.4 to 9.0 Ryell and similar soils: 0 to 4 percent Hanly and similar soils: 0 to 3 percent Areas of channels with steep slopes: 0 to 2 percent 61A—Glendive sandy loam, Poorly drained and ponded soils: 0 to 2 percent 0 to 2 percent slopes Major Component Description Surface layer texture: Sandy loam Setting Depth class: Very deep (more than 60 inches) Landform: Flood plains Drainage class: Moderately well drained Slope: 0 to 2 percent Dominant parent material: Alluvium Mean annual precipitation: 12 to 15 inches Native plant cover type: Rangeland Flooding: Rare Composition Water table: Apparent Major Components Salt affected: Saline within 30 inches Glendive and similar soils: 85 percent Sodium affected: Sodic within 30 inches Available water capacity: Mainly 5.7 inches Minor Components Havre and similar soils: 0 to 4 percent A typical soil description with range in Hanly and similar soils: 0 to 4 percent characteristics is included, in alphabetical order, Ryell and similar soils: 0 to 3 percent in this section. Poorly drained and ponded soils: 0 to 2 percent Areas of channels with steep slopes: 0 to 1 percent Management Major Component Description For management information about this map unit, see appropriate sections in Part II of this publication. Surface layer texture: Sandy loam Depth class: Very deep (more than 60 inches) Drainage class: Well drained Hanly Series Dominant parent material: Alluvium Native plant cover type: Rangeland Depth class: Very deep (more than 60 inches) Flooding: Rare Drainage class: Somewhat excessively drained Available water capacity: Mainly 9.8 inches Permeability: Rapid (6.0 to 20.0 inches/hour) Landform: Flood plains A typical soil description with range in Parent material: Alluvium characteristics is included, in alphabetical order, Slope range: 0 to 4 percent in this section. Annual precipitation: 12 to 15 inches Management Taxonomic Class: Sandy, mixed, frigid Aridic For management information about this map unit, Ustifluvents see appropriate sections in Part II of this publication. Typical Pedon Hanly fine sandy loam, in an area of Hanly-Ryell fine 161B—Glendive sandy loam, saline, sandy loams, 0 to 4 percent slopes, in an area of 0 to 4 percent slopes cropland, 2,400 feet north and 1,000 feet west of the southeast corner of sec. 5, T. 2 N., R. 58 E. Setting Ap—0 to 6 inches; light brownish gray (2.5Y 6/2) fine Landform: Flood plains sandy loam, dark grayish brown (2.5Y 4/2) moist; Slope: 0 to 4 percent weak medium granular structure; soft, very Mean annual precipitation: 12 to 15 inches friable, nonsticky, nonplastic; common fine and many very fine roots; slightly alkaline; abrupt Composition smooth boundary. Major Components C1—6 to 15 inches; grayish brown (2.5Y 5/2) fine Glendive and similar soils: 85 percent sandy loam consisting of thin strata of sandy Carter County, Montana—Part I 99

loam and loamy sand, dark grayish brown (2.5Y Composition 4/2) moist; weak medium subangular blocky Major Components structure parting to weak fine granular; soft, very Hanly and similar soils: 50 percent friable, nonsticky, nonplastic; common very fine Ryell and similar soils: 35 percent roots; moderately alkaline; clear smooth boundary. Minor Components C2—15 to 30 inches; light brownish gray (2.5Y 6/2) Havre and similar soils: 0 to 5 percent loamy sand consisting of thin strata of loamy fine Glendive and similar soils: 0 to 5 percent sand and sand, dark grayish brown (2.5Y 4/2) Poorly drained and ponded soils: 0 to 3 percent moist; single grain; loose, nonsticky, nonplastic; Areas of channels with steep slopes: 0 to 2 percent few very fine roots; disseminated lime; slightly Major Component Description effervescent; moderately alkaline; clear smooth boundary. Hanly C3—30 to 60 inches; light gray (2.5Y 7/2) loamy sand Surface layer texture: Fine sandy loam consisting of thin strata of loamy fine sand and Depth class: Very deep (more than 60 inches) sand, light brownish gray (2.5Y 6/2) moist; single Drainage class: Somewhat excessively drained grain; loose, nonsticky, nonplastic; disseminated Dominant parent material: Alluvium lime; slightly effervescent; moderately alkaline. Native plant cover type: Rangeland Flooding: Rare Range in Characteristics Available water capacity: Mainly 5.9 inches Ap horizon Ryell Hue: 10YR or 2.5Y Surface layer texture: Fine sandy loam Value: 5, 6, or 7 dry; 4, 5, or 6 moist Depth class: Very deep (more than 60 inches) Chroma: 2 or 3 Drainage class: Well drained Clay content: 10 to 20 percent Dominant parent material: Alluvium Content of rock fragments: 0 to 15 percent—0 to Native plant cover type: Rangeland 5 percent cobbles; 0 to 10 percent pebbles Flooding: Rare Reaction: pH 6.6 to 8.4 Available water capacity: Mainly 5.7 inches C horizons Hue: 10YR, 2.5Y, or 5Y A typical soil description with range in Value: 5, 6, or 7 dry; 4, 5, or 6 moist characteristics is included, in alphabetical order, Chroma: 2 to 4 in this section. Clay content: 5 to 10 percent Management Content of rock fragments: 0 to 10 percent pebbles below 40 inches For management information about this map unit, Calcium carbonate equivalent: 1 to 5 percent see appropriate sections in Part II of this publication. Reaction: pH 7.4 to 8.4 Haploborolls 7B—Hanly-Ryell fine sandy loams, 0 to 4 percent slopes Depth class: Deep (40 to 60 inches) to very deep (more than 60 inches) Drainage class: Well drained Setting Permeability: Moderately slow (0.2 to 0.6 inch/hour) Landform: to moderately rapid (2.0 to 6.0 inches/hour) • Hanly—Flood plains Landform: Hills (slump area) • Ryell—Flood plains Parent material: Alluvium and colluvium Slope: Slope range: 15 to 45 percent • Hanly—0 to 4 percent Annual precipitation: 12 to 15 inches • Ryell—0 to 4 percent Mean annual precipitation: 12 to 15 inches Taxonomic Class: Aridic Haploborolls 100 Soil Survey

Typical Pedon Bk horizon Clay content: 5 to 35 percent Haploborolls, in an area of Ustochrepts-Haploborolls Calcium carbonate equivalent: 5 to 15 percent complex, slump, 15 to 45 percent slopes, in an area Reaction: pH 7.4 to 9.0 of rangeland, 950 feet north and 50 feet east of the southwest corner of sec. 8, T. 4 S., R. 60 E. C horizon Clay content: 5 to 35 percent A—0 to 6 inches; brown (10YR 5/3) channery fine Reaction: pH 7.4 to 9.0 sandy loam, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky, nonplastic; many very fine Harlake Series and fine roots; few very fine pores; 20 percent channers; slightly alkaline; clear smooth Depth class: Very deep (more than 60 inches) boundary. Drainage class: Well drained or moderately well Bw—6 to 13 inches; brown (10YR 5/3) channery fine drained sandy loam, dark brown (10YR 3/3) moist; weak Permeability: Slow (0.06 to 0.2 inch/hour) fine subangular blocky structure; slightly hard, Landform: Flood plains very friable, nonsticky, slightly plastic; common Parent material: Alluvium fine and many very fine roots; few very fine pores; Slope range: 0 to 3 percent 30 percent channers; disseminated lime; slightly Annual precipitation: 12 to 15 inches effervescent; slightly alkaline; clear smooth boundary. Taxonomic Class: Fine, montmorillonitic Bk—13 to 25 inches; pale brown (10YR 6/3) fine (calcareous), frigid Aridic Ustifluvents sandy loam, brown (10YR 4/3) moist; moderate Typical Pedon medium subangular blocky structure; slightly hard, very friable, nonsticky, slightly plastic; Harlake silty clay loam, 0 to 2 percent slopes, in an common very fine and fine roots; few very fine area of rangeland, 1,100 feet north and 650 feet east pores; 10 percent channers; 60 percent soft of the southwest corner of sec. 19, T. 5 S., R. 55 E. coarse fragments; few fine and medium masses A—0 to 10 inches; grayish brown (2.5Y 5/2) silty clay and seams of lime; violently effervescent; loam, dark grayish brown (2.5Y 4/2) moist; moderately alkaline; clear wavy boundary. moderate medium subangular blocky structure C—25 to 60 inches; pale brown (10YR 6/3) fine parting to moderate fine and medium granular; sandy loam, dark grayish brown (10YR 4/2) hard, firm, very sticky, very plastic; common very moist; weak coarse subangular blocky structure; fine roots; few very fine pores; moderately slightly hard, very friable, nonsticky, nonplastic; alkaline; abrupt smooth boundary. 40 percent soft coarse fragments; disseminated C1—10 to 27 inches; light brownish gray (10YR 6/2) lime; violently effervescent; moderately alkaline. silty clay loam, dark grayish brown (10YR 4/2) moist; strong medium subangular blocky Range in Characteristics structure parting to moderate fine and medium Thickness of the mollic epipedon: 7 to 16 inches granular; hard, very firm, very sticky, very plastic; Rock fragments in the control section: 0 to 35 percent common very fine roots; few very fine pores; channers or flagstones disseminated lime; slightly effervescent; Soft coarse fragments in the control section: 0 to moderately alkaline; clear wavy boundary. 80 percent C2—27 to 40 inches; light brownish gray (10YR 6/2) Depth to calcium carbonate: 0 to 35 inches silty clay, dark grayish brown (10YR 4/2) moist; Other features: Rock fragments occur in the upper massive; hard, very firm, very sticky, moderately portion of the profile; soft coarse fragments plastic; few very fine roots; few thin strata of clay commonly increase with depth. loam; disseminated lime; strongly effervescent; moderately alkaline; clear wavy boundary. A horizon C3—40 to 60 inches; light brownish gray (10YR 6/2) Clay content: 5 to 18 percent silty clay, dark grayish brown (10YR 4/2) moist; Reaction: pH 6.6 to 7.8 massive; hard, very firm, very sticky, moderately Bw horizon plastic; few very fine roots; few thin strata of clay Clay content: 5 to 18 percent loam; disseminated lime; slightly effervescent; Reaction: pH 6.6 to 7.8 moderately alkaline. Carter County, Montana—Part I 101

Range in Characteristics 57A—Harlake silty clay, saline, Soil temperature: 42 to 47 degrees F 0 to 2 percent slopes Soil phases: Saline or warm Taxonomic note: Map units 606B and 608B are Setting taxadjuncts to the Harlake series in order to join Landform: Flood plains soils that have an average soil temperature Slope: 0 to 2 percent greater than 47 degrees F. Mean annual precipitation: 12 to 15 inches A horizon Composition Hue: 10YR or 2.5Y Value: 4, 5, or 6 dry; 4 or 5 moist Major Components Chroma: 2 or 3 Harlake and similar soils: 85 percent Texture: Silty clay loam, silty clay, or clay Minor Components Clay content: 27 to 55 percent Havre and similar soils: 0 to 5 percent Electrical conductivity: 0 to 4 mmhos/cm; saline Nonsaline soils: 0 to 5 percent phase: 4 to 8 mmhos/cm Soils with silty clay loam surfaces: 0 to 3 percent Sodium adsorption ratio: 0 to 8 Poorly drained and ponded soils: 0 to 2 percent Calcium carbonate equivalent: 1 to 5 percent Reaction: pH 6.6 to 8.4 Major Component Description C1 horizon Surface layer texture: Silty clay Hue: 10YR, 2.5Y, or 5Y Depth class: Very deep (more than 60 inches) Value: 4, 5, 6, or 7 dry; 4 or 5 moist Drainage class: Moderately well drained Chroma: 2 or 3 Dominant parent material: Alluvium Texture: Clay; silty clay, or silty clay loam Native plant cover type: Rangeland consisting of stratified layers of clay, silt loam, Flooding: Rare silty clay loam, and silty clay Water table: Apparent Clay content: 35 to 60 percent Salt affected: Saline within 30 inches Electrical conductivity: 0 to 4 mmhos/cm; saline Sodium affected: Sodic within 30 inches phase: 8 to 16 mmhos/cm Available water capacity: Mainly 6.8 inches Sodium adsorption ratio: 4 to 10; saline phase: 13 to 30 A typical soil description with range in Calcium carbonate equivalent: 2 to 10 percent characteristics is included, in alphabetical order, Reaction: pH 7.4 to 9.0 in this section. C2 and C3 horizons Management Hue: 10YR, 2.5Y, or 5Y For management information about this map unit, Value: 4, 5, 6, or 7 dry; 4 or 5 moist see appropriate sections in Part II of this publication. Chroma: 2 or 3 Texture: Clay; silty clay, or silty clay loam consisting of stratified layers of clay, silt loam, silty clay loam, and silty clay 157A—Harlake silty clay loam, Clay content: 35 to 60 percent 0 to 2 percent slopes Electrical conductivity: 0 to 4 mmhos/cm; saline phase: 8 to 16 mmhos/cm Setting Sodium adsorption ratio: 4 to 10; saline phase: 13 to 30 Landform: Flood plains Calcium carbonate equivalent: 2 to 10 percent Slope: 0 to 2 percent Reaction: pH 7.4 to 9.0 Mean annual precipitation: 12 to 15 inches 102 Soil Survey

Composition Dominant parent material: Alluvium Native plant cover type: Rangeland Major Components Flooding: Rare Harlake and similar soils: 90 percent Water table: Apparent Minor Components Salt affected: Saline within 30 inches Havre and similar soils: 0 to 3 percent Sodium affected: Sodic within 30 inches Moderately saline soils: 0 to 3 percent Available water capacity: Mainly 7.0 inches Moderately sodic soils: 0 to 2 percent Areas of channels with steep slopes: 0 to 1 percent A typical soil description with range in Poorly drained and ponded soils: 0 to 1 percent characteristics is included, in alphabetical order, in this section. Major Component Description Management Surface layer texture: Silty clay loam Depth class: Very deep (more than 60 inches) For management information about this map unit, Drainage class: Well drained see appropriate sections in Part II of this publication. Dominant parent material: Alluvium Native plant cover type: Rangeland Flooding: Rare 608B—Harlake clay, warm, Available water capacity: Mainly 9.6 inches 0 to 3 percent slopes

A typical soil description with range in Setting characteristics is included, in alphabetical order, Landform: Flood plains in this section. Slope: 0 to 3 percent Management Mean annual precipitation: 12 to 15 inches For management information about this map unit, Composition see appropriate sections in Part II of this publication. Major Components Harlake and similar soils: 85 percent 606B—Harlake silty clay loam, warm, Minor Components saline, 0 to 3 percent slopes Havre and similar soils: 0 to 5 percent Moderately saline soils: 0 to 3 percent Setting Moderately sodic soils: 0 to 3 percent Areas of channels with steep slopes: 0 to 2 percent Landform: Flood plains Poorly drained and ponded soils: 0 to 2 percent Slope: 0 to 3 percent Mean annual precipitation: 12 to 15 inches Major Component Description Composition Surface layer texture: Clay Depth class: Very deep (more than 60 inches) Major Components Drainage class: Well drained Harlake and similar soils: 85 percent Dominant parent material: Alluvium Minor Components Native plant cover type: Rangeland Havre and similar soils: 0 to 5 percent Flooding: Rare Nonsaline soils: 0 to 4 percent Available water capacity: Mainly 9.6 inches Soils that are noncalcareous throughout: 0 to 3 percent A typical soil description with range in Poorly drained and ponded soils: 0 to 3 percent characteristics is included, in alphabetical order, in this section. Major Component Description Management Surface layer texture: Silty clay loam Depth class: Very deep (more than 60 inches) For management information about this map unit, Drainage class: Moderately well drained see appropriate sections in Part II of this publication. Carter County, Montana—Part I 103

Havre Series C1 horizon Hue: 10YR, 2.5Y, or 5Y Depth class: Very deep (more than 60 inches) Value: 5 or 6 dry; 4 or 5 moist Drainage class: Well drained or moderately well Chroma: 2 or 3 drained Texture: Loam, silt loam, or clay loam that consist Permeability: Moderate (0.6 to 2.0 inches/hour) of strata of silt loam, fine sandy loam, silty clay Landform: Flood plains loam, and clay loam Parent material: Alluvium Clay content: 18 to 35 percent Slope range: 0 to 4 percent Calcium carbonate equivalent: 1 to 10 percent Annual precipitation: 12 to 15 inches Electrical conductivity: 0 to 4 mmhos/cm; saline phase: 8 to 16 mmhos/cm Taxonomic Class: Fine-loamy, mixed (calcareous), Sodium adsorption ratio: 0 to 4; saline phase: frigid Aridic Ustifluvents 13 to 30 Reaction: pH 7.4 to 9.0 Typical Pedon C2 horizon Havre loam, 0 to 2 percent slopes, in an area of Hue: 10YR, 2.5Y, or 5Y cropland, 2,150 feet south and 750 feet west of Value: 5 or 6 dry; 4 or 5 moist the northeast corner of sec. 9, T. 5 S., R. 62 E. Chroma: 2 or 3 Ap—0 to 5 inches; brown (10YR 5/3) loam, dark Texture: Loam, silt loam, or clay loam that consist grayish brown (10YR 4/2) moist; weak very fine of strata of silt loam, fine sandy loam, silty clay and fine granular structure; soft, very friable, loam, and clay loam slightly sticky, slightly plastic; common very fine Clay content: 18 to 35 percent and fine roots; neutral; abrupt smooth boundary. Calcium carbonate equivalent: 1 to 10 percent C1—5 to 25 inches; pale brown (10YR 6/3) silty clay Electrical conductivity: 0 to 4 mmhos/cm; saline loam, dark grayish brown (10YR 4/2) moist; phase: 8 to 16 mmhos/cm massive; hard, friable, slightly sticky, slightly Sodium adsorption ratio: 0 to 4; saline phase: plastic; common very fine and fine roots; common 13 to 30 very fine and fine pores; disseminated lime; Reaction: pH 7.4 to 9.0 slightly effervescent; moderately alkaline; clear smooth boundary. C2—25 to 60 inches; pale brown (10YR 6/3) loam, 56A—Havre loam, 0 to 2 percent slopes dark grayish brown (10YR 4/2) moist; massive; slightly hard, friable, slightly sticky, slightly plastic; few very fine roots; few very fine pores; few thin Setting strata of fine sandy loam, loam, and clay loam; disseminated lime; slightly effervescent; Landform: Flood plains moderately alkaline. Slope: 0 to 2 percent Mean annual precipitation: 12 to 15 inches Range in Characteristics Soil temperature: 40 to 47 degrees F Composition Soil phases: Saline Major Components Ap horizon Havre and similar soils: 85 percent Hue: 10YR or 2.5Y Value: 5 or 6 dry; 4 or 5 moist Minor Components Chroma: 2 or 3 Harlake and similar soils: 0 to 4 percent Clay content: 15 to 27 percent Glendive and similar soils: 0 to 4 percent Calcium carbonate equivalent: 0 to 5 percent Soils with darker colored surface layers: 0 to Electrical conductivity: 0 to 2 mmhos/cm; saline 3 percent phase: 8 to 16 mmhos/cm Areas of channels with steep slopes: 0 to 2 percent Sodium adsorption ratio: 0 to 4 Moderately saline soils: 0 to 1 percent Reaction: pH 6.1 to 9.0 Poorly drained and ponded soils: 0 to 1 percent 104 Soil Survey

Major Component Description Management Surface layer texture: Loam For management information about this map unit, Depth class: Very deep (more than 60 inches) see appropriate sections in Part II of this publication. Drainage class: Well drained Dominant parent material: Alluvium Native plant cover type: Rangeland Flooding: Rare 256A—Havre-Harlake complex, Available water capacity: Mainly 9.7 inches 0 to 2 percent slopes

A typical soil description with range in Setting characteristics is included, in alphabetical order, in this section. Landform: • Havre—Flood plains Management • Harlake—Flood plains For management information about this map unit, Slope: see appropriate sections in Part II of this publication. • Havre—0 to 2 percent • Harlake—0 to 2 percent Mean annual precipitation: 12 to 15 inches 156A—Havre loam, saline, 0 to 2 percent slopes Composition Major Components Setting Havre and similar soils: 50 percent Landform: Flood plains Harlake and similar soils: 40 percent Slope: 0 to 2 percent Minor Components Mean annual precipitation: 12 to 15 inches Glendive and similar soils: 0 to 3 percent Composition Very deep silt loam soils: 0 to 2 percent Moderately saline soils: 0 to 2 percent Major Components Areas of channels with steep slopes: 0 to 2 percent Havre and similar soils: 85 percent Poorly drained and ponded soils: 0 to 1 percent Minor Components Harlake and similar soils: 0 to 4 percent Major Component Description Glendive and similar soils: 0 to 4 percent Nonsaline soils: 0 to 2 percent Havre Areas of channels with steep slopes: 0 to 2 percent Surface layer texture: Loam Soils that are noncalcareous throughout: 0 to Depth class: Very deep (more than 60 inches) 2 percent Drainage class: Well drained Poorly drained and ponded soils: 0 to 1 percent Dominant parent material: Alluvium Native plant cover type: Rangeland Major Component Description Flooding: Rare Surface layer texture: Loam Available water capacity: Mainly 9.7 inches Depth class: Very deep (more than 60 inches) Drainage class: Moderately well drained Harlake Dominant parent material: Alluvium Surface layer texture: Silty clay loam Native plant cover type: Rangeland Depth class: Very deep (more than 60 inches) Flooding: Rare Drainage class: Well drained Water table: Apparent Dominant parent material: Alluvium Salt affected: Saline within 30 inches Native plant cover type: Rangeland Sodium affected: Sodic within 30 inches Flooding: Rare Available water capacity: Mainly 6.6 inches Available water capacity: Mainly 9.6 inches

A typical soil description with range in A typical soil description with range in characteristics is included, in alphabetical order, characteristics is included, in alphabetical order, in this section. in this section. Carter County, Montana—Part I 105

Management soft shale fragments; 25 percent hard shale channers; very strongly acid; clear wavy For management information about this map unit, boundary. see appropriate sections in Part II of this publication. C3—21 to 28 inches; light brownish gray (10YR 6/2) silty clay, grayish brown (10YR 4/2) moist; massive; hard, friable, moderately sticky, Julin Series moderately plastic; few very fine roots; 45 percent soft shale fragments; 20 percent hard shale Depth class: Moderately deep (20 to 40 inches) channers; very strongly acid; clear wavy Drainage class: Well drained boundary. Permeability: Slow (0.06 to 0.2 inch/hour) Cr—28 to 60 inches; light brownish gray (10YR 6/2) Landform: Hills and sedimentary plains semiconsolidated shale, dark grayish brown Parent material: Semiconsolidated shale (10YR 4/2) moist; sulphur coats on some shale Slope range: 6 to 25 percent fragments. Annual precipitation: 12 to 15 inches Range in Characteristics Taxonomic Class: Fine, montmorillonitic, acid, frigid Soil temperature: 44 to 47 degrees F Aridic Ustorthents Depth to the Cr horizon: 20 to 40 inches Typical Pedon Taxonomic note: Map unit 634E is a taxadjunct to the Julin series in order to join soils that have Julin silty clay loam, in an area of Volborg-Julin-Rock an average soil temperature greater than outcrop complex, 8 to 25 percent slopes, in an area 47 degrees F. of rangeland, 2,500 feet north and 200 feet west of the southeast corner of sec. 31, T. 9 S., R. 59 E. A horizons Hue: 10YR, 2.5Y, or 5Y A1—0 to 3 inches; light brownish gray (10YR 6/2) Value: 5 or 6 dry; 3 or 4 moist silty clay loam, dark grayish brown (10YR 4/2) Chroma: 1 to 3 moist; moderate medium subangular blocky Clay content: 35 to 40 percent structure parting to moderate fine granular; Content of rock fragments: 0 to 35 percent shale slightly hard, friable, slightly sticky, moderately fragments—0 to 25 percent soft shale; 0 to plastic; many very fine and fine roots; few very 10 percent hard shale fine and fine pores; 10 percent soft shale Reaction: pH 3.6 to 5.5 fragments, very strongly acid; clear smooth boundary. C horizons A2—3 to 7 inches; light brownish gray (10YR 6/2) Hue: 10YR, 2.5Y, or 5Y silty clay loam, dark grayish brown (10YR 4/2) Value: 5 or 6 dry; 3 or 4 moist moist; moderate medium subangular blocky Chroma: 1 to 3 structure parting to moderate fine granular; Texture: Silty clay or clay slightly hard, friable, moderately sticky, Clay content: 40 to 55 percent moderately plastic; common very fine and fine Content of rock fragments: 30 to 85 percent shale roots; few very fine pores; 5 percent soft shale fragments—25 to 60 percent soft shale; 5 to fragments; strongly acid; clear smooth boundary. 25 percent hard shale C1—7 to 15 inches; light brownish gray (10YR 6/2) Reaction: pH 3.6 to 5.5 silty clay, grayish brown (10YR 4/2) moist; Cr horizon moderate medium subangular blocky structure Material: Semiconsolidated shale parting to moderate fine and medium granular; Reaction: pH 3.6 to 5.5 slightly hard, friable, moderately sticky, moderately plastic; few fine and common very fine roots; few very fine and fine pores; Kirby Series 25 percent soft shale fragments; 5 percent hard shale channers; very strongly acid; clear smooth Depth class: Very deep (more than 60 inches) boundary. Drainage class: Excessively drained C2—15 to 21 inches; pale brown (10YR 6/3) silty Permeability: Rapid (6.0 to 20.0 inches/hour) clay, brown (10YR 4/3) moist; massive; hard, Landform: Hills friable, moderately sticky, moderately plastic; few Parent material: Colluvium and residuum from scorio very fine roots; few very fine pores; 35 percent (baked shale and sandstone) 106 Soil Survey

Slope range: 8 to 60 percent Chroma: 3, 4, or 6 Annual precipitation: 12 to 15 inches Texture: Loam or sandy loam Clay content: 8 to 22 percent Taxonomic Class: Loamy-skeletal over fragmental, Content of rock fragments: 40 to 90 percent—5 to mixed (calcareous), frigid Aridic Ustorthents 20 percent flagstones and cobbles; 35 to 70 percent channers Typical Pedon Calcium carbonate equivalent: 5 to 15 percent Kirby channery loam, in an area of Kirby-Cabbart Reaction: pH 7.9 to 8.4 complex, 8 to 25 percent slopes, in an area of 2C horizon rangeland, 50 feet north and 2,250 feet west of Features: This horizon consists of highly fractured the southeast corner of sec. 21, T. 1 N., R. 62 E. and displaced scorio. The coloring of this A—0 to 6 inches; reddish brown (5YR 5/3) channery material ranges from reddish gray (10R 6/1) loam, reddish brown (5YR 4/4) moist; weak fine through yellowish red (5YR 4/6). Rock granular structure; soft, very friable, nonsticky, fragments of stones, flagstones, and channers nonplastic; common very fine and fine roots; make up 90 to 95 percent of this horizon. 30 percent channers; disseminated lime; strongly effervescent; moderately alkaline; clear wavy boundary. 176D—Kirby-Cabbart complex, Bk—6 to 11 inches; light reddish brown (5YR 6/4) 8 to 25 percent slopes extremely channery loam, yellowish red (5YR 4/6) moist; massive; soft, very friable, nonsticky, Setting nonplastic; common very fine and fine roots Landform: matted between channers; 70 percent channers • Kirby—Hills and 5 percent flagstones; common fine masses • Cabbart—Hills of lime; common distinct lime coats on rock Position on landform: fragments; disseminated lime; violently • Kirby—Shoulders and summits effervescent; moderately alkaline; gradual wavy • Cabbart—Backslopes and shoulders boundary. Slope: 2C—11 to 60 inches; yellowish red (5YR 5/6) hard, • Kirby—8 to 25 percent shattered and fractured scorio, reddish brown • Cabbart—8 to 25 percent (5YR 4/4) moist; few fine roots in fractures; Mean annual precipitation: 12 to 15 inches common thin lime coats on lower surfaces of rock fragments in the upper few inches. Composition Range in Characteristics Major Components Kirby and similar soils: 50 percent Soil temperature: 42 to 47 degrees F Cabbart and similar soils: 35 percent Depth to fragmental material: 11 to 20 inches Other features: The rock fragments in the Kirby soil Minor Components are called scorio. Scorio is defined as the product Bonfri and similar soils: 0 to 3 percent resulting from the baking of shale and sandstone Delpoint and similar soils: 0 to 3 percent bedrock that was adjacent to burning coal beds. Yamacall and similar soils: 0 to 3 percent Very shallow loamy soils: 0 to 2 percent A horizon Areas of rock outcrop: 0 to 2 percent Hue: 5YR or 7.5YR Soils that have slopes more than 25 percent: 0 to Value: 5 or 6 dry; 4 or 5 moist 2 percent Chroma: 3, 4, or 6 Clay content: 10 to 22 percent Major Component Description Content of rock fragments: 15 to 70 percent—0 to Kirby 5 percent flagstones; 15 to 65 percent Surface layer texture: Channery loam channers Depth class: Very deep (more than 60 inches) Reaction: pH 7.4 to 8.4 Drainage class: Excessively drained Bk horizon Dominant parent material: Material weathered from Hue: 2.5YR, 5YR, or 7.5YR baked sandstone and shale Value: 5, 6, or 7 dry; 4, 5, or 6 moist Native plant cover type: Rangeland Carter County, Montana—Part I 107

Flooding: None Major Component Description Available water capacity: Mainly 1.3 inches Kirby Surface layer texture: Channery loam Cabbart Depth class: Very deep (more than 60 inches) Surface layer texture: Silt loam Drainage class: Excessively drained Depth class: Shallow (10 to 20 inches) Dominant parent material: Material weathered from Drainage class: Well drained baked sandstone and shale Dominant parent material: Semiconsolidated, loamy Native plant cover type: Rangeland sedimentary beds Flooding: None Native plant cover type: Rangeland Available water capacity: Mainly 1.3 inches Flooding: None Available water capacity: Mainly 2.2 inches Blacksheep Surface layer texture: Fine sandy loam A typical soil description with range in Depth class: Shallow (10 to 20 inches) characteristics is included, in alphabetical order, Drainage class: Well drained in this section. Dominant parent material: Semiconsolidated, sandy Management sedimentary beds Native plant cover type: Rangeland For management information about this map unit, Flooding: None see appropriate sections in Part II of this publication. Available water capacity: Mainly 2.3 inches

276F—Kirby-Blacksheep-Rock outcrop Rock outcrop complex, 25 to 60 percent slopes Definition: Mainly consolidated baked shale and sandstone Setting A typical soil description with range in Landform: characteristics is included, in alphabetical order, • Kirby—Hills in this section. • Blacksheep—Hills • Rock outcrop—Hills Management Position on landform: For management information about this map unit, • Kirby—Shoulders and summits see appropriate sections in Part II of this publication. • Blacksheep—Backslopes and shoulders Slope: • Kirby—25 to 60 percent • Blacksheep—25 to 50 percent Kobase Series Mean annual precipitation: 12 to 15 inches Depth class: Very deep (more than 60 inches) Composition Drainage class: Well drained Permeability: Slow (0.06 to 0.2 inch/hour) Major Components Landform: Alluvial fans and stream terraces Kirby and similar soils: 40 percent Parent material: Alluvium Blacksheep and similar soils: 35 percent Slope range: 0 to 8 percent Rock outcrop: 15 percent Annual precipitation: 12 to 15 inches Minor Components Cabbart and similar soils: 0 to 2 percent Taxonomic Class: Fine, montmorillonitic, frigid Aridic Twilight and similar soils: 0 to 2 percent Ustochrepts Very shallow loamy soils: 0 to 2 percent Typical Pedon Cambeth and similar soils: 0 to 2 percent Soils with stony surface layers: 0 to 1 percent Kobase silty clay loam, 2 to 8 percent slopes, in an Soils that have slopes less than 25 percent: 0 to area of rangeland, 500 feet north and 300 feet west 1 percent of the southeast corner of sec. 26, T. 4 S., R. 56 E. 108 Soil Survey

A—0 to 5 inches; grayish brown (2.5Y 5/2) silty clay Electrical conductivity: 0 to 2 mmhos/cm loam, dark grayish brown (2.5Y 4/2) moist; weak Reaction: pH 7.4 to 8.4 medium subangular blocky structure parting to Bk horizon moderate very fine and fine granular; very hard, Hue: 10YR, 2.5Y, or 5Y friable, very sticky, moderately plastic; few Value: 5, 6, or 7 dry; 4, 5, or 6 moist medium and common very fine and fine roots; Chroma: 2 to 4 few very fine, fine, and medium pores; neutral; Texture: Silty clay loam, silty clay, or clay clear smooth boundary. Clay content: 35 to 45 percent Bw—5 to 12 inches; light brownish gray (2.5Y 6/2) Content of rock fragments: 0 to 5 percent pebbles silty clay, grayish brown (2.5Y 5/2) moist; Calcium carbonate equivalent: 5 to 15 percent moderate coarse prismatic structure parting to Sodium adsorption ratio: 5 to 10 strong medium subangular blocky; very hard, Electrical conductivity: 0 to 4 mmhos/cm firm, very sticky, very plastic; common very fine Reaction: pH 7.9 to 9.0 and fine roots; few fine and common very fine pores; disseminated lime; slightly effervescent; Bky horizon moderately alkaline; gradual wavy boundary. Hue: 10YR, 2.5Y, or 5Y Bk—12 to 29 inches; light brownish gray (2.5Y 6/2) Value: 5, 6, or 7 dry; 4, 5, or 6 moist silty clay, grayish brown (2.5Y 5/2) moist; weak Chroma: 1 to 4 medium and coarse subangular blocky structure; Texture: Silty clay loam, silty clay, or clay extremely hard, firm, moderately sticky, very Clay content: 35 to 45 percent plastic; few very fine roots; few very fine and fine Content of rock fragments: 0 to 5 percent pebbles pores; common fine masses of lime; violently Calcium carbonate equivalent: 5 to 15 percent effervescent; strongly alkaline; gradual wavy Sodium adsorption ratio: 8 to 13 boundary. Electrical conductivity: 0 to 4 mmhos/cm Bky—29 to 60 inches; light brownish gray (2.5Y 6/2) Gypsum content: 1 to 5 percent clay, dark grayish brown (2.5Y 4/2) moist; Reaction: pH 7.9 to 9.0 massive; extremely hard, firm, moderately sticky, very plastic; few very fine roots; few very fine pores; common fine nests of gypsum crystals; 78A—Kobase silty clay loam, common fine masses of lime; strongly 0 to 2 percent slopes effervescent; moderately alkaline. Setting Range in Characteristics Landform: Alluvial fans and stream terraces Soil temperature: 42 to 47 degrees F Slope: 0 to 2 percent Depth to the Bk horizon: 12 to 17 inches Mean annual precipitation: 12 to 15 inches Depth to the Bky horizon: 25 to 40 inches Composition A horizon Hue: 10YR or 2.5Y Major Components Value: 5 or 6 dry; 4 or 5 moist Kobase and similar soils: 85 percent Chroma: 2 or 3 Minor Components Clay content: 27 to 40 percent Marias and similar soils: 0 to 3 percent Content of rock fragments: 0 to 5 percent pebbles Marvan and similar soils: 0 to 3 percent Electrical conductivity: 0 to 2 mmhos/cm Orinoco and similar soils: 0 to 3 percent Reaction: pH 6.6 to 8.4 Soils with silt loam surface layers: 0 to 3 percent Bw horizon Soils with darker colored surface layers: 0 to 3 Hue: 10YR, 2.5Y, or 5Y percent Value: 5 or 6 dry; 4 or 5 moist Major Component Description Chroma: 1 to 4 Texture: Silty clay loam, silty clay, or clay Surface layer texture: Silty clay loam Clay content: 35 to 45 percent Depth class: Very deep (more than 60 inches) Content of rock fragments: 0 to 5 percent pebbles Drainage class: Well drained Calcium carbonate equivalent: 5 to 10 percent Dominant parent material: Alluvium Carter County, Montana—Part I 109

Native plant cover type: Rangeland Permeability: Moderate (0.6 to 2.0 inches/hour) Flooding: None Landform: Alluvial fans and stream terraces Available water capacity: Mainly 9.7 inches Parent material: Alluvium Slope range: 0 to 8 percent A typical soil description with range in Annual precipitation: 12 to 15 inches characteristics is included, in alphabetical order, in this section. Taxonomic Class: Fine-loamy, mixed Aridic Haploborolls Management For management information about this map unit, Typical Pedon see appropriate sections in Part II of this publication. Kremlin loam, 2 to 8 percent slopes, in an area of cropland, 1,450 feet north and 1,400 feet east of the 78C—Kobase silty clay loam, southwest corner of sec. 9, T. 7 S., R. 55 E. 2 to 8 percent slopes Ap1—0 to 4 inches; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; weak Setting fine subangular blocky structure parting to Landform: Alluvial fans and stream terraces moderate fine and medium granular; soft, very Slope: 2 to 8 percent friable, slightly sticky, slightly plastic; few medium Mean annual precipitation: 12 to 15 inches and many very fine and fine roots; few very fine and fine pores; neutral; clear wavy boundary. Composition Ap2—4 to 8 inches; grayish brown (10YR 5/2) loam, Major Components very dark grayish brown (10YR 3/2) moist; Kobase and similar soils: 85 percent moderate thick platy structure parting to moderate fine subangular blocky; hard, friable, Minor Components slightly sticky, slightly plastic; few medium and Marias and similar soils: 0 to 3 percent many very fine and fine roots; few very fine pores; Marvan and similar soils: 0 to 3 percent neutral; clear smooth boundary. Orinoco and similar soils: 0 to 3 percent Bw—8 to 13 inches; brown (10YR 5/3) loam, dark Soils with silt loam surface layers: 0 to 3 percent brown (10YR 3/3) moist; weak medium prismatic Soils with darker colored surface layers: 0 to 3 structure parting to moderate fine and medium percent subangular blocky; hard, friable, slightly sticky, Major Component Description slightly plastic; few fine and common very fine roots; few very fine pores; neutral; clear wavy Surface layer texture: Silty clay loam boundary. Depth class: Very deep (more than 60 inches) Bk1—13 to 32 inches; gray (10YR 6/2) loam, grayish Drainage class: Well drained brown (10YR 5/2) moist; weak fine and medium Dominant parent material: Alluvium subangular blocky structure; hard, very friable, Native plant cover type: Rangeland slightly sticky, slightly plastic; few very fine roots; Flooding: None few very fine pores; few fine and medium masses Available water capacity: Mainly 9.7 inches of lime; violently effervescent; moderately alkaline; clear wavy boundary. A typical soil description with range in Bk2—32 to 60 inches; pale brown (10YR 6/3) clay characteristics is included, in alphabetical order, loam, brown (10YR 4/3) moist; massive; slightly in this section. hard, very friable, moderately sticky, moderately Management plastic; common fine masses of lime and few medium masses of lime; violently effervescent; For management information about this map unit, moderately alkaline. see appropriate sections in Part II of this publication. Range in Characteristics Kremlin Series Soil temperature: 42 to 47 degrees F Depth class: Very deep (more than 60 inches) Thickness of the mollic epipedon: 7 to 15 inches Drainage class: Well drained Depth to the Bk horizon: 10 to 24 inches 110 Soil Survey

Ap1 horizon 72A—Kremlin loam, 0 to 2 percent slopes Hue: 10YR or 2.5Y Value: 2 or 3 moist Setting Chroma: 2 or 3 Clay content: 18 to 27 percent Landform: Alluvial fans and stream terraces Content of rock fragments: 0 to 5 percent pebbles Slope: 0 to 2 percent Reaction: pH 6.1 to 7.8 Mean annual precipitation: 12 to 15 inches Ap2 horizon Composition Hue: 10YR or 2.5Y Value: 4 or 5 dry; 3 or 4 moist Major Components Chroma: 2 or 3 Kremlin and similar soils: 85 percent Clay content: 18 to 27 percent Content of rock fragments: 0 to 5 percent pebbles Minor Components Reaction: pH 6.6 to 7.8 Eapa and similar soils: 0 to 3 percent Cambeth and similar soils: 0 to 3 percent Bw horizon Delpoint and similar soils: 0 to 3 percent Hue: 10YR or 2.5Y Busby and similar soils: 0 to 2 percent Value: 4, 5, or 6 dry; 3 to 5 moist Soils with gravelly surface layers: 0 to 2 percent Chroma: 2 or 3 Soils with lighter colored surface layers: 0 to Texture: Loam, silt loam, clay loam, or sandy clay 2 percent loam Clay content: 18 to 30 percent Major Component Description Content of rock fragments: 0 to 5 percent pebbles Reaction: pH 6.6 to 7.8 Surface layer texture: Loam Bk1 horizon Depth class: Very deep (more than 60 inches) Hue: 10YR or 2.5Y Drainage class: Well drained Value: 5, 6, or 7 dry; 4, 5, or 6 moist Dominant parent material: Alluvium Chroma: 2 or 3 Native plant cover type: Rangeland Texture: Loam, silt loam, clay loam, or sandy clay Flooding: None loam Available water capacity: Mainly 10.8 inches Clay content: 18 to 30 percent Content of rock fragments: 0 to 5 percent pebbles A typical soil description with range in Calcium carbonate equivalent: 5 to 15 percent characteristics is included, in alphabetical order, Electrical conductivity: 0 to 2 mmhos/cm in this section. Reaction: pH 7.4 to 8.4 Management Bk2 horizon Hue: 10YR, 2.5Y, or 5Y For management information about this map unit, Value: 6, 7, or 8 dry; 4, 5, or 6 moist see appropriate sections in Part II of this publication. Chroma: 2 to 4 Texture: Loam, silt loam, clay loam, or sandy clay loam consisting of thin layers of different 72C—Kremlin loam, 2 to 8 percent slopes textures Clay content: 18 to 30 percent Setting Content of rock fragments: 0 to 5 percent pebbles Calcium carbonate equivalent: 5 to 12 percent Landform: Alluvial fans and stream terraces Electrical conductivity: 0 to 2 mmhos/cm Slope: 2 to 8 percent Reaction: pH 7.4 to 8.4 Mean annual precipitation: 12 to 15 inches Carter County, Montana—Part I 111

Composition Very deep clayey soils: 0 to 2 percent Soils with slopes more than 8 percent: 0 to 2 percent Major Components Kremlin and similar soils: 85 percent Major Component Description Minor Components Kremlin Eapa and similar soils: 0 to 3 percent Surface layer texture: Loam Chinook and similar soils: 0 to 3 percent Depth class: Very deep (more than 60 inches) Delpoint and similar soils: 0 to 3 percent Drainage class: Well drained Soils with gravelly surface layers: 0 to 2 percent Dominant parent material: Alluvium Busby and similar soils: 0 to 2 percent Native plant cover type: Rangeland Soils with lighter colored surface layers: 0 to Flooding: None 2 percent Available water capacity: Mainly 10.8 inches Major Component Description Cabbart Surface layer texture: Loam Surface layer texture: Silt loam Depth class: Very deep (more than 60 inches) Depth class: Shallow (10 to 20 inches) Drainage class: Well drained Drainage class: Well drained Dominant parent material: Alluvium Dominant parent material: Semiconsolidated, loamy Native plant cover type: Rangeland sedimentary beds Flooding: None Native plant cover type: Rangeland Available water capacity: Mainly 10.8 inches Flooding: None Available water capacity: Mainly 2.2 inches A typical soil description with range in characteristics is included, in alphabetical order, A typical soil description with range in in this section. characteristics is included, in alphabetical order, in this section. 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. 172C—Kremlin-Cabbart complex, 2 to 8 percent slopes Marias Series Depth class: Very deep (more than 60 inches) Setting Drainage class: Well drained Landform: Permeability: Very slow (<0.06 inch/hour) • Kremlin—Alluvial fans Landform: Alluvial fans and stream terraces • Cabbart—Sedimentary plains Parent material: Alluvium Slope: Slope range: 0 to 8 percent • Kremlin—2 to 8 percent Annual precipitation: 12 to 15 inches • Cabbart—2 to 8 percent Mean annual precipitation: 12 to 15 inches Taxonomic Class: Fine, montmorillonitic, frigid Chromic Udic Haplusterts Composition Typical Pedon Major Components Kremlin and similar soils: 50 percent Marias silty clay loam, 0 to 2 percent slopes, in an Cabbart and similar soils: 35 percent area of rangeland, 1,900 feet north and 350 feet east of the southwest corner of sec. 2, T. 8 S., R. 60 E. Minor Components Cambeth and similar soils: 0 to 3 percent A—0 to 4 inches; light brownish gray (2.5Y 6/2) silty Marmarth and similar soils: 0 to 3 percent clay loam, dark grayish brown (2.5Y 4/2) moist; Very shallow loamy soils: 0 to 3 percent strong very fine granular structure; soft, friable, Moderately saline soils: 0 to 2 percent moderately sticky, moderately plastic; many very 112 Soil Survey

fine and fine roots; slightly alkaline; clear smooth Texture: Clay or silty clay boundary. Clay content: 40 to 60 percent Bss1—4 to 10 inches; light brownish gray (2.5Y 6/2) Electrical conductivity: 0 to 4 mmhos/cm silty clay, dark grayish brown (2.5Y 4/2) moist; Sodium adsorption ratio: 1 to 4 strong fine and medium subangular blocky Calcium carbonate equivalent: 5 to 10 percent structure; very hard, firm, moderately sticky, very Reaction: pH 7.9 to 9.0 plastic; many very fine and fine roots; few very Bssy horizon fine pores; few slickensides; disseminated lime; Hue: 10YR, 2.5Y, or 5Y slightly effervescent; moderately alkaline; gradual Value: 5 or 6 dry; 3, 4, or 5 moist smooth boundary. Chroma: 1 to 3 Bss2—10 to 23 inches; light brownish gray (2.5Y 6/2) Texture: Clay or silty clay silty clay, dark grayish brown (2.5Y 4/2) moist; Clay content: 40 to 60 percent strong fine and medium subangular blocky Gypsum content: 1 to 6 percent structure; very hard, firm, moderately sticky, very Electrical conductivity: 2 to 8 mmhos/cm plastic; common very fine roots; few very fine Sodium adsorption ratio: 4 to 13 pores; few slickensides; disseminated lime; Calcium carbonate equivalent: 5 to 10 percent slightly effervescent; moderately alkaline; gradual Reaction: pH 7.9 to 9.0 smooth boundary. Bssy—23 to 60 inches; light brownish gray (2.5Y 6/2) silty clay, dark grayish brown (2.5Y 4/2) moist; 94A—Marias silty clay loam, massive; very hard, firm, very sticky, very plastic; 0 to 2 percent slopes few very fine roots; common distinct slickensides; common fine and medium nests and seams of Setting gypsum crystals; moderately alkaline. Landform: Alluvial fans and stream terraces Range in Characteristics Slope: 0 to 2 percent Soil temperature: 42 to 47 degrees F Mean annual precipitation: 12 to 15 inches Depth to the Bssy horizon: 20 to 45 inches Composition Linear extensibility: .06 to .10 in the upper 30 inches 1 of soil; /4- to 2-inch wide cracks to a depth of Major Components 20 inches Marias and similar soils: 85 percent A horizon Minor Components Hue: 10YR, 2.5Y, or 5Y Ethridge and similar soils: 0 to 4 percent Value: 4, 5, or 6 dry; 3, 4, or 5 moist Gerdrum and similar soils: 0 to 4 percent Chroma: 1 to 3 Marvan and similar soils: 0 to 4 percent Clay content: 27 to 40 percent Soils with darker colored surface layers: 0 to Electrical conductivity: 0 to 4 mmhos/cm 3 percent Sodium adsorption ratio: 1 to 4 Major Component Description Reaction: pH 7.4 to 8.4 Surface layer texture: Silty clay loam Bss1 horizon Depth class: Very deep (more than 60 inches) Hue: 10YR, 2.5Y, or 5Y Drainage class: Well drained Value: 5 or 6 dry; 4 or 5 moist Dominant parent material: Alluvium Chroma: 2 or 3 Native plant cover type: Rangeland Texture: Clay or silty clay Flooding: None Clay content: 40 to 60 percent Available water capacity: Mainly 8.6 inches Electrical conductivity: 0 to 4 mmhos/cm Sodium adsorption ratio: 1 to 4 A typical soil description with range in Calcium carbonate equivalent: 5 to 10 percent characteristics is included, in alphabetical order, Reaction: pH 7.9 to 8.4 in this section. Bss2 horizon Management Hue: 10YR, 2.5Y, or 5Y Value: 5 or 6 dry; 4 or 5 moist For management information about this map unit, Chroma: 2 or 3 see appropriate sections in Part II of this publication. Carter County, Montana—Part I 113

94C—Marias silty clay loam, Typical Pedon 2 to 8 percent slopes Marmarth loam, 2 to 8 percent slopes, in an area of rangeland, 600 feet north and 2,500 feet west of the Setting southeast corner of sec. 36, T. 9 S., R. 62 E. Landform: Alluvial fans and stream terraces A—0 to 4 inches; grayish brown (10YR 5/2) loam, Slope: 2 to 8 percent very dark grayish brown (10YR 3/2) moist; weak Mean annual precipitation: 12 to 15 inches very fine subangular blocky structure parting to moderate fine and medium granular; soft, very Composition friable, nonsticky, slightly plastic; common very Major Components fine and fine roots; few fine and common very fine Marias and similar soils: 85 percent pores; neutral; clear smooth boundary. Bt—4 to 13 inches; brown (10YR 5/3) clay loam, dark Minor Components brown (10YR 3/3) moist; moderate medium Ethridge and similar soils: 0 to 4 percent prismatic structure parting to strong fine and Marvan and similar soils: 0 to 4 percent medium subangular blocky; hard, firm, slightly Gerdrum and similar soils: 0 to 4 percent sticky, moderately plastic; few fine and common Soils with darker colored surface layers: 0 to very fine roots; few fine and common very fine 3 percent tubular pores; continuous distinct clay films on Major Component Description faces of peds, continuous prominent clay films in pores; neutral; clear wavy boundary. Surface layer texture: Silty clay loam Bk1—13 to 18 inches; pale brown (10YR 6/3) clay Depth class: Very deep (more than 60 inches) loam, brown (10YR 5/3) moist; moderate medium Drainage class: Well drained prismatic structure parting to moderate medium Dominant parent material: Alluvium subangular blocky; slightly hard, firm, slightly Native plant cover type: Rangeland sticky, moderately plastic; few very fine roots; few Flooding: None very fine pores; common fine masses of lime; Available water capacity: Mainly 8.6 inches slightly effervescent; slightly alkaline; clear smooth boundary. A typical soil description with range in Bk2—18 to 27 inches; light olive gray (5Y 6/2) loam, characteristics is included, in alphabetical order, olive gray (5Y 4/2) moist; weak medium in this section. subangular blocky structure; soft, friable, Management nonsticky, slightly plastic; few very fine roots; many very fine and fine masses of lime; strongly For management information about this map unit, effervescent; moderately alkaline; clear smooth see appropriate sections in Part II of this publication. boundary. Cr—27 to 60 inches; light brownish gray (5Y 6/2) Marmarth Series semiconsolidated, loamy sedimentary beds that crush to a sandy loam, olive brown (2.5Y 4/4) Depth class: Moderately deep (20 to 40 inches) moist. Drainage class: Well drained Permeability: Moderate (0.6 to 2.0 inches/hour) Range in Characteristics Landform: Sedimentary plains Parent material: Semiconsolidated, loamy Thickness of the mollic epipedon: 7 to 16 inches sedimentary beds Depth to the Bk horizon: 12 to 24 inches Slope range: 2 to 8 percent Depth to the Cr horizon: 20 to 40 inches Annual precipitation: 12 to 15 inches Taxonomic note: Map unit 629C is a taxadjunct to the Marmarth series in order to join soils that Taxonomic Class: Fine-loamy, mixed Aridic have an average soil temperature greater than Argiborolls 47 degrees F. 114 Soil Survey

A horizon A typical soil description with range in Value: 3, 4, or 5 moist characteristics is included, in alphabetical order, Chroma: 2 or 3 in this section. Clay content: 20 to 27 percent Management Reaction: pH 6.1 to 7.3 For management information about this map unit, Bt horizon see appropriate sections in Part II of this pub Hue: 10YR or 2.5Y Value: 3, 4, 5, or 6 moist Chroma: 2 to 4 629C—Marmarth loam, warm, Texture: Loam, clay loam, or sandy clay loam 2 to 8 percent slopes Clay content: 18 to 35 percent Reaction: pH 6.1 to 7.8 Setting Bk horizons Landform: Sedimentary plains Hue: 10YR, 2.5Y, or 5Y Slope: 2 to 8 percent Value: 5, 6, or 7 dry; 4, 5, or 6 moist Mean annual precipitation: 12 to 15 inches Chroma: 2 to 4 Texture: Loam, fine sandy loam, or clay loam Composition Clay content: 15 to 30 percent Major Components Calcium carbonate equivalent: 5 to 15 percent Marmarth and similar soils: 85 percent Reaction: pH 7.4 to 8.4 Minor Components Cabbart and similar soils: 0 to 4 percent 81C—Marmarth loam, Cambeth and similar soils: 0 to 3 percent 2 to 8 percent slopes Delpoint and similar soils: 0 to 3 percent Eapa and similar soils: 0 to 3 percent Moderately saline soils: 0 to 2 percent Setting Major Component Description Landform: Sedimentary plains Slope: 2 to 8 percent Surface layer texture: Loam Mean annual precipitation: 12 to 15 inches Depth class: Moderately deep (20 to 40 inches) Drainage class: Well drained Composition Dominant parent material: Semiconsolidated, loamy Major Components sedimentary beds Marmarth and similar soils: 85 percent Native plant cover type: Rangeland Flooding: None Minor Components Available water capacity: Mainly 4.6 inches Cabbart and similar soils: 0 to 4 percent Eapa and similar soils: 0 to 3 percent A typical soil description with range in Delpoint and similar soils: 0 to 3 percent characteristics is included, in alphabetical order, Moderately saline soils: 0 to 3 percent in this section. Cambeth and similar soils: 0 to 2 percent Management Major Component Description For management information about this map unit, Surface layer texture: Loam see appropriate sections in Part II of this publication. Depth class: Moderately deep (20 to 40 inches) Drainage class: Well drained Dominant parent material: Semiconsolidated, loamy Marvan Series sedimentary beds Native plant cover type: Rangeland Depth class: Very deep (more than 60 inches) Flooding: None Drainage class: Well drained Available water capacity: Mainly 4.5 inches Permeability: Very slow (<0.06 inch/hour) Carter County, Montana—Part I 115

1 Landform: Alluvial fans, stream terraces, and Other features: When dry, this soil has /4- to 1-inch sedimentary plains cracks that extend to a depth of about 20 inches. Parent material: Alluvium Slickensides range from few to common in all Slope range: 0 to 8 percent horizons except the surface. Annual precipitation: 12 to 15 inches Taxonomic note: Map units 613B, 614C, and 635C are taxadjuncts to the Marvan series in order to Taxonomic Class: Fine, montmorillonitic, frigid Sodic join soils that have an average soil temperature Haplusterts greater than 47 degrees F. Typical Pedon Ap horizon Marvan silty clay, 0 to 2 percent slopes, in an area of Hue: 2.5Y or 5Y cropland, 1,000 feet north and 2,500 feet west of the Value: 5 or 6 dry; 4 or 5 moist southeast corner of sec. 1, T. 2 S., R. 58 E. Chroma: 2 to 4 Texture: Clay or silty clay Ap—0 to 7 inches; light brownish gray (2.5Y 6/2) silty Clay content: 40 to 60 percent clay, grayish brown (2.5Y 5/2) moist; strong fine Electrical conductivity: 0 to 4 mmhos/cm and medium subangular blocky structure; hard, Sodium adsorption ratio: 0 to 4 firm, moderately sticky, moderately plastic; many Calcium carbonate equivalent: 1 to 5 percent very fine and fine roots; few very fine and fine Reaction: pH 7.4 to 8.4 pores; disseminated lime; slightly effervescent; slightly alkaline; gradual smooth boundary. Bss horizon Bss—7 to 18 inches; light brownish gray (2.5Y 6/2) Hue: 2.5Y or 5Y clay, grayish brown (2.5Y 5/2) moist; moderate Value: 5 or 6 dry; 4 or 5 moist medium prismatic structure; very hard, firm, Chroma: 2 to 4 moderately sticky, moderately plastic; many very Texture: Clay or silty clay fine and fine roots; few very fine pores; few Clay content: 45 to 60 percent slickensides; disseminated lime; slightly Electrical conductivity: 2 to 4 mmhos/cm effervescent; moderately alkaline; gradual smooth Sodium adsorption ratio: 4 to 13 boundary. Calcium carbonate equivalent: 5 to 10 percent Bssy—18 to 32 inches; light brownish gray (2.5Y 6/2) Reaction: pH 7.9 to 9.0 clay, dark grayish brown (2.5Y 4/2) moist; strong Bssy horizon fine and medium subangular blocky structure; Hue: 2.5Y or 5Y extremely hard, very firm, moderately sticky, very Value: 5 or 6 dry; 4 or 5 moist plastic; few fine and common very fine roots; few Chroma: 2 to 4 very fine pores; few slickensides; common fine Texture: Clay or silty clay nests and seams of gypsum crystals; Clay content: 45 to 60 percent disseminated lime; slightly effervescent; Gypsum content: 1 to 3 percent moderately alkaline; gradual smooth boundary. Electrical conductivity: 2 to 8 mmhos/cm Bssyz—32 to 60 inches; light brownish gray (2.5Y Sodium adsorption ratio: 4 to 13 6/2) clay, dark grayish brown (2.5Y 4/2) moist; Calcium carbonate equivalent: 5 to 10 percent massive; very hard, very firm, moderately sticky, Reaction: pH 7.9 to 9.0 very plastic; few very fine roots; few distinct slickensides; common fine and medium nests Bssyz horizon and seams of gypsum crystals; few fine seams of Hue: 2.5Y or 5Y other salts; disseminated lime; slightly Value: 5 or 6 dry; 4 or 5 moist effervescent; moderately alkaline. Chroma: 2 to 4 Texture: Clay or silty clay Range in Characteristics Clay content: 45 to 60 percent Soil temperature: 42 to 47 degrees F Gypsum content: 1 to 5 percent Depth to the Bssy horizon: 10 to 24 inches Electrical conductivity: 4 to 16 mmhos/cm Soil phases: Warm Sodium adsorption ratio: 13 to 38 116 Soil Survey

Calcium carbonate equivalent: 5 to 10 percent Minor Components Reaction: pH 7.9 to 9.0 Kobase and similar soils: 0 to 3 percent Teigen and similar soils: 0 to 3 percent Vaeda and similar soils: 0 to 3 percent 89A—Marvan silty clay, Vanda and similar soils: 0 to 2 percent 0 to 2 percent slopes Absher and similar soils: 0 to 2 percent Areas of slickspots: 0 to 2 percent Setting Major Component Description Landform: Alluvial fans and stream terraces Slope: 0 to 2 percent Surface layer texture: Silty clay Mean annual precipitation: 12 to 15 inches Depth class: Very deep (more than 60 inches) Composition Drainage class: Well drained Dominant parent material: Alluvium Major Components Native plant cover type: Rangeland Marvan and similar soils: 85 percent Flooding: None Minor Components Available water capacity: Mainly 6.8 inches Kobase and similar soils: 0 to 4 percent Teigen and similar soils: 0 to 3 percent A typical soil description with range in Vaeda and similar soils: 0 to 3 percent characteristics is included, in alphabetical order, Vanda and similar soils: 0 to 3 percent in this section. Areas of slickspots: 0 to 2 percent Management Major Component Description For management information about this map unit, Surface layer texture: Silty clay see appropriate sections in Part II of this publication. Depth class: Very deep (more than 60 inches) Drainage class: Well drained Dominant parent material: Alluvium Native plant cover type: Rangeland 613B—Marvan-Vanda clays, warm, Flooding: None 0 to 3 percent slopes Available water capacity: Mainly 6.9 inches Setting A typical soil description with range in characteristics is included, in alphabetical order, Landform: in this section. • Marvan—Alluvial fans and stream terraces • Vanda—Alluvial fans and stream terraces Management Slope: For management information about this map unit, • Marvan—0 to 3 percent see appropriate sections in Part II of this publication. • Vanda—0 to 3 percent Mean annual precipitation: 12 to 15 inches 89C—Marvan silty clay, Composition 2 to 8 percent slopes Major Components Marvan and similar soils: 45 percent Setting Vanda and similar soils: 40 percent Landform: Alluvial fans and stream terraces Minor Components Slope: 2 to 8 percent Very deep nonsaline soils: 0 to 4 percent Mean annual precipitation: 12 to 15 inches Vaeda and similar soils: 0 to 3 percent Gerdrum and similar soils: 0 to 3 percent Composition Areas of slickspots: 0 to 3 percent Major Components Soils that have slopes more than 3 percent: 0 to Marvan and similar soils: 85 percent 2 percent Carter County, Montana—Part I 117

Major Component Description Native plant cover type: Rangeland Flooding: None Marvan Available water capacity: Mainly 6.9 inches Surface layer texture: Clay Depth class: Very deep (more than 60 inches) A typical soil description with range in Drainage class: Well drained characteristics is included, in alphabetical order, Dominant parent material: Alluvium in this section. Native plant cover type: Rangeland Flooding: None Management Available water capacity: Mainly 6.9 inches For management information about this map unit, see appropriate sections in Part II of this publication. Vanda Surface layer texture: Clay Depth class: Very deep (more than 60 inches) Drainage class: Well drained 635C—Marvan-Bascovy clays, warm, Dominant parent material: Alluvium 0 to 6 percent slopes Native plant cover type: Rangeland Flooding: None Setting Salt affected: Saline within 30 inches Landform: Sodium affected: Sodic within 30 inches • Marvan—Alluvial fans Available water capacity: Mainly 6.0 inches • Bascovy—Sedimentary plains Slope: A typical soil description with range in • Marvan—0 to 6 percent characteristics is included, in alphabetical order, • Bascovy—0 to 6 percent in this section. Mean annual precipitation: 12 to 15 inches Management Composition For management information about this map unit, Major Components see appropriate sections in Part II of this publication. Marvan and similar soils: 50 percent Bascovy and similar soils: 35 percent 614C—Marvan clay, warm, Minor Components 0 to 6 percent slopes Neldore and similar soils: 0 to 4 percent Kobase and similar soils: 0 to 3 percent Setting Orinoco and similar soils: 0 to 3 percent Soils that have slopes more than 6 percent: 0 to Landform: Alluvial fans and stream terraces 3 percent Slope: 0 to 6 percent Marias and similar soils: 0 to 2 percent Mean annual precipitation: 12 to 15 inches Major Component Description Composition Marvan Major Components Surface layer texture: Clay Marvan and similar soils: 85 percent Depth class: Very deep (more than 60 inches) Minor Components Drainage class: Well drained Yamacall and similar soils: 0 to 4 percent Dominant parent material: Alluvium Absher and similar soils: 0 to 3 percent Native plant cover type: Rangeland Vaeda and similar soils: 0 to 3 percent Flooding: None Kobase and similar soils: 0 to 3 percent Available water capacity: Mainly 6.9 inches Areas of slickspots: 0 to 2 percent Bascovy Major Component Description Surface layer texture: Clay Surface layer texture: Clay Depth class: Moderately deep (20 to 40 inches) Depth class: Very deep (more than 60 inches) Drainage class: Well drained Drainage class: Well drained Dominant parent material: Semiconsolidated shale Dominant parent material: Alluvium residuum 118 Soil Survey

Native plant cover type: Rangeland channers, 10 percent flagstones, and 5 percent Flooding: None cobbles; neutral; abrupt smooth boundary. Sodium affected: Sodic within 30 inches Bw—2 to 11 inches; olive (5Y 5/3) very channery Available water capacity: Mainly 5.3 inches loam, olive (5Y 4/3) moist; moderate coarse subangular blocky structure parting to moderate A typical soil description with range in fine granular; hard, very friable, slightly sticky, characteristics is included, in alphabetical order, slightly plastic; few coarse and many very fine, in this section. fine, and medium roots; common fine and many very fine pores; 20 percent channers, 15 percent Management flagstones, and 10 percent cobbles; neutral; clear smooth boundary. For management information about this map unit, Bk—11 to 22 inches; olive (5Y 5/3) very flaggy loam, see appropriate sections in Part II of this publication. dark grayish brown (2.5Y 4/2) moist; weak fine granular structure; slightly hard, very friable, M-W—Miscellaneous water slightly sticky, slightly plastic; few coarse and common very fine and fine roots; common very fine pores; 20 percent flagstones, 15 percent Composition cobbles, and 15 percent channers; 40 percent Major Components soft channers; many distinct lime coats on coarse Miscellaneous Water: 100 percent fragments; violently effervescent; slightly alkaline; gradual wavy boundary. Major Component Description BC—22 to 60 inches; grayish brown (2.5Y 5/2) very Definition: Open water in areas such as sewage flaggy loam, dark grayish brown (2.5Y 4/2) moist; lagoons, industrial waste pits, and fish hatcheries weak very thin platy structure; soft, very friable, slightly sticky, slightly plastic; few fine, medium, and coarse roots; few very fine pores; 30 percent Mowbray Series flagstones, 10 percent cobbles, 10 percent channers, and 20 percent soft channers; Depth class: Very deep (more than 60 inches) disseminated lime; strongly effervescent; Drainage class: Well drained moderately alkaline. Permeability: Moderate (0.6 to 2.0 inches/hour) Landform: Hills Range in Characteristics Parent material: Colluvium Slope range: 15 to 60 percent Soil temperature: 42 to 47 degrees F Annual precipitation: 15 to 17 inches Depth to the Bk horizon: 10 to 20 inches A horizon Taxonomic Class: Loamy-skeletal, mixed, frigid Hue: 10YR or 2.5Y Typic Ustochrepts Value: 4, 5, or 6 dry; 2, 3, or 4 moist Typical Pedon Chroma: 2 or 3 Clay content: 15 to 25 percent Mowbray very channery loam, in an area of Content of rock fragments: 35 to 60 percent—5 to Mowbray-Cabba-Vebar complex, 35 to 60 percent 10 percent cobbles; 10 to 20 percent slopes, in an area of forestland, 2,150 feet north and flagstones; 20 to 35 percent channers 1,400 feet east of the southwest corner of sec. 5, Reaction: pH 6.6 to 7.8 T. 3 S., R. 62 E. Bw horizon Oi—2 inches to 0; undecomposed and slightly Hue: 10YR, 2.5Y, or 5Y decomposed forest litter. Value: 5 or 6 dry; 4 or 5 moist A—0 to 2 inches; dark grayish brown (2.5Y 4/2) very Chroma: 2 or 3 channery loam, very dark grayish brown (2.5Y Texture: Loam or sandy loam 3/2) moist; moderate medium subangular blocky Clay content: 15 to 27 percent structure; slightly hard, very friable, slightly sticky, Content of rock fragments: 30 to 65 percent—0 to slightly plastic; many very fine and fine roots; few 10 percent cobbles; 15 to 25 percent fine and many very fine pores; 20 percent flagstones; 20 to 45 percent channers Carter County, Montana—Part I 119

Soft fragments: 0 to 20 percent Soils with darker colored surface layers: 0 to Reaction: pH 6.6 to 7.8 3 percent Soils that have slopes more than 60 percent: 0 to Bk horizon 2 percent Hue: 10YR, 2.5Y, or 5Y Value: 5 or 6 dry; 4 or 5 moist Major Component Description Chroma: 2 or 3 Texture: Loam or sandy loam Mowbray Clay content: 15 to 27 percent Surface layer texture: Very channery loam Content of rock fragments: 40 to 80 percent—0 to Depth class: Very deep (more than 60 inches) 15 percent cobbles; 15 to 25 percent Drainage class: Well drained flagstones; 15 to 45 percent channers Dominant parent material: Colluvium Soft fragments: 10 to 40 percent Native plant cover type: Forestland Calcium carbonate equivalent: 5 to 15 percent Flooding: None Reaction: pH 7.4 to 8.4 Available water capacity: Mainly 4.4 inches BC horizon Hue: 2.5Y or 5Y Cabba Value: 5 or 6 dry; 4 or 5 moist Surface layer texture: Very stony loam Chroma: 2 to 4 Depth class: Shallow (10 to 20 inches) Clay content: 15 to 27 percent Drainage class: Well drained Content of rock fragments: 35 to 65 percent—0 to Dominant parent material: Semiconsolidated, loamy 10 percent cobbles; 25 to 35 percent sedimentary beds flagstones; 10 to 25 percent channers Native plant cover type: Rangeland Soft coarse fragments: 10 to 40 percent Flooding: None Calcium carbonate equivalent: 0 to 15 percent Available water capacity: Mainly 2.2 inches Reaction: pH 7.4 to 8.4 Vebar Surface layer texture: Fine sandy loam 152F—Mowbray-Cabba-Vebar complex, Depth class: Moderately deep (20 to 40 inches) 35 to 60 percent slopes Drainage class: Well drained Dominant parent material: Semiconsolidated, sandy sedimentary beds Setting Native plant cover type: Forestland Flooding: None Landform: Available water capacity: Mainly 3.4 inches • Mowbray—Hills • Cabba—Hills A typical soil description with range in • Vebar—Hills characteristics is included, in alphabetical order, Slope: in this section. • Mowbray—35 to 60 percent • Cabba—35 to 60 percent Management • Vebar—35 to 50 percent For management information about this map unit, Mean annual precipitation: 15 to 17 inches see appropriate sections in Part II of this publication. Composition Major Components Moyerson Series Mowbray and similar soils: 35 percent Depth class: Shallow (10 to 20 inches) Cabba and similar soils: 25 percent Drainage class: Well drained Vebar and similar soils: 25 percent Permeability: Slow (0.06 to 0.2 inch/hour) Minor Components Landform: Sedimentary plains and hills Dast and similar soils: 0 to 4 percent Parent material: Semiconsolidated shale Areas of rock outcrop: 0 to 3 percent Slope range: 4 to 50 percent Very shallow loamy soils: 0 to 3 percent Annual precipitation: 12 to 15 inches 120 Soil Survey

Taxonomic Class: Clayey, montmorillonitic Electrical conductivity: 0 to 4 mmhos/cm (calcareous), frigid, shallow Ustic Torriorthents Reaction: pH 7.4 to 8.4 Typical Pedon C1 horizon Hue: 5Y, 2.5Y, 10YR, or 7.5YR Moyerson silty clay loam, in an area of Rock outcrop- Value: 5, 6, or 7 dry; 3, 4, 5, or 6 moist Moyerson complex, 15 to 50 percent slopes, in an Chroma: 1 to 4 area of rangeland, 1,200 feet north and 1,400 feet Clay content: 35 to 60 percent west of the southeast corner of sec. 27, T. 6 S., Electrical conductivity: 8 to 16 mmhos/cm R. 58 E. Sodium adsorption ratio: 5 to 13 Gypsum content: 1 to 5 percent A—0 to 4 inches; pale brown (10YR 6/3) silty clay Reaction: pH 7.4 to 8.4 loam, brown (10YR 4/3) moist; moderate fine subangular blocky structure parting to strong fine C2 horizon granular; hard, friable, moderately sticky, slightly Hue: 5Y, 2.5Y, 10YR, or 7.5YR plastic; many very fine and fine roots; few fine Value: 5, 6, or 7 dry; 3, 4, 5, or 6 moist and common very fine pores; disseminated lime; Chroma: 1 to 4 strongly effervescent; slightly alkaline; gradual Clay content: 35 to 60 percent wavy boundary. Electrical conductivity: 8 to 16 mmhos/cm C1—4 to 8 inches; light brownish gray (10YR 6/2) Sodium adsorption ratio: 5 to 13 silty clay loam, grayish brown (10YR 5/2) moist; Reaction: pH 7.4 to 8.4 weak medium prismatic structure parting to strong very fine subangular blocky; hard, friable, moderately sticky, slightly plastic; common very 77D—Moyerson silty clay loam, fine roots; few very fine and fine tubular pores; 4 to 15 percent slopes few fine masses, nests, and seams of gypsum crystals; few fine seams and nests of other salts Setting crystals; disseminated lime; strongly effervescent; slightly alkaline; clear smooth boundary. Landform: Sedimentary plains and hills C2—8 to 14 inches; light brownish gray (2.5Y 6/2) Slope: 4 to 15 percent silty clay loam, grayish brown (2.5Y 5/2) moist; Mean annual precipitation: 12 to 15 inches massive; hard, firm, moderately sticky, Composition moderately plastic; few very fine roots; disseminated lime; slightly effervescent; slightly Major Components alkaline; gradual wavy boundary. Moyerson and similar soils: 85 percent Cr—14 to 60 inches; light brownish gray (2.5Y 6/2) Minor Components semiconsolidated shale that crushes to silty clay Very shallow clayey soils: 0 to 4 percent loam, grayish brown (2.5Y 5/2) moist. Neldore and similar soils: 0 to 4 percent Bascovy and similar soils: 0 to 4 percent Range in Characteristics Marvan and similar soils: 0 to 3 percent Depth to the Cr horizon: 10 to 20 inches Major Component Description Soil phases: Saline or warm Surface layer texture: Silty clay loam Taxonomic note: The Moyerson soil is a taxadjunct to Depth class: Shallow (10 to 20 inches) the series. It classifies as Clayey, montmorillonitic Drainage class: Well drained (calcareous), frigid, shallow Aridic Ustorthents. Dominant parent material: Semiconsolidated shale Use and management are similar. Map unit 605E residuum is a taxadjunct to the Moyerson series in order to Native plant cover type: Rangeland join soils that have an average soil temperature Flooding: None greater than 47 degrees F. Salt affected: Saline within 30 inches A horizon Available water capacity: Mainly 1.8 inches Hue: 5Y, 2.5Y, 10YR, or 7.5YR Value: 5, 6, or 7 dry; 3, 4, 5, or 6 moist A typical soil description with range in Chroma: 1 to 4 characteristics is included, in alphabetical order, Clay content: 30 to 40 percent in this section. Carter County, Montana—Part I 121

Management A typical soil description with range in characteristics is included, in alphabetical order, For management information about this map unit, in this section. see appropriate sections in Part II of this publication. Management 277D—Moyerson-Orinoco silty clay For management information about this map unit, loams, 4 to 15 percent slopes see appropriate sections in Part II of this publication.

Setting 477E—Moyerson silty clay loam, Landform: 15 to 35 percent slopes • Moyerson—Sedimentary plains and hills • Orinoco—Hills Setting Position on landform: Landform: Hills • Moyerson—Shoulders and summits Slope: 15 to 35 percent • Orinoco—Backslopes and footslopes Mean annual precipitation: 12 to 15 inches Slope: • Moyerson—4 to 15 percent Composition • Orinoco—4 to 15 percent Major Components Mean annual precipitation: 12 to 15 inches Moyerson and similar soils: 85 percent Composition Minor Components Major Components Very shallow clayey soils: 0 to 4 percent Moyerson and similar soils: 50 percent Neldore and similar soils: 0 to 4 percent Orinoco and similar soils: 40 percent Bascovy and similar soils: 0 to 4 percent Marvan and similar soils: 0 to 3 percent Minor Components Very shallow clayey soils: 0 to 3 percent Major Component Description Bascovy and similar soils: 0 to 3 percent Surface layer texture: Silty clay loam Marvan and similar soils: 0 to 2 percent Depth class: Shallow (10 to 20 inches) Vanda and similar soils: 0 to 2 percent Drainage class: Well drained Major Component Description Dominant parent material: Semiconsolidated shale residuum Moyerson Native plant cover type: Rangeland Surface layer texture: Silty clay loam Flooding: None Depth class: Shallow (10 to 20 inches) Salt affected: Saline within 30 inches Drainage class: Well drained Available water capacity: Mainly 1.8 inches Dominant parent material: Semiconsolidated shale residuum A typical soil description with range in Native plant cover type: Rangeland characteristics is included, in alphabetical order, Flooding: None in this section. Salt affected: Saline within 30 inches Available water capacity: Mainly 1.8 inches Management For management information about this map unit, Orinoco see appropriate sections in Part II of this publication. Surface layer texture: Silty clay loam Depth class: Moderately deep (20 to 40 inches) Drainage class: Well drained 605E—Moyerson, warm-Rock outcrop Dominant parent material: Semiconsolidated shale complex, 9 to 45 percent slopes residuum Native plant cover type: Rangeland Setting Flooding: None Salt affected: Saline within 30 inches Landform: Sodium affected: Sodic within 30 inches • Moyerson—Hills Available water capacity: Mainly 3.8 inches • Rock outcrop—Hills 122 Soil Survey

Slope: 9 to 45 percent rangeland, 250 feet south and 485 feet west of the Mean annual precipitation: 12 to 15 inches northeast corner of sec. 26, T. 9 S., R. 58 E. Composition A—0 to 2 inches; grayish brown (10YR 5/2) clay, dark grayish brown (10YR 4/2) moist; weak medium Major Components platy structure parting to strong fine granular; Moyerson and similar soils: 55 percent hard, firm, very sticky, very plastic; few fine and Rock outcrop: 30 percent many very fine roots; few very fine and fine pores; Minor Components neutral; clear smooth boundary. Very shallow clayey soils: 0 to 4 percent C1—2 to 6 inches; grayish brown (10YR 5/2) clay, Neldore and similar soils: 0 to 4 percent dark grayish brown (10YR 4/2) moist; moderate Bascovy and similar soils: 0 to 4 percent medium subangular blocky structure; hard, firm, Marvan and similar soils: 0 to 3 percent very sticky, very plastic; few fine and common very fine roots; few very fine pores; slightly Major Component Description alkaline; gradual smooth boundary. Moyerson C2—6 to 12 inches; yellowish brown (10YR 5/4) clay, Surface layer texture: Silty clay loam dark yellowish brown (10YR 4/4) moist; massive; Depth class: Shallow (10 to 20 inches) hard, firm, very sticky, very plastic; few very fine Drainage class: Well drained roots; slightly alkaline; gradual wavy boundary. Dominant parent material: Semiconsolidated shale Cr—12 to 60 inches; dark gray (10YR 4/1) residuum semiconsolidated shale, very dark gray (10YR Native plant cover type: Rangeland 3/1) moist. Flooding: None Salt affected: Saline within 30 inches Range in Characteristics Available water capacity: Mainly 1.8 inches Soil temperature: 42 to 47 degrees F Rock outcrop Depth to the Cr horizon: 10 to 20 inches Definition: Consolidated shale Taxonomic note: Map units 625E and 633D are taxadjuncts to the Neldore series in order to join A typical soil description with range in soils that have an average soil temperature characteristics is included, in alphabetical order, greater than 47 degrees F. in this section. A horizon Management Hue: 10YR, 2.5Y, or 5Y Value: 4, 5, or 6 dry; 3, 4, or 5 moist For management information about this map unit, Chroma: 1 or 2 see appropriate sections in Part II of this publication. Clay content: 40 to 50 percent Electrical conductivity: 0 to 2 mmhos/cm Neldore Series Reaction: pH 5.6 to 7.8 C1 horizon Depth class: Shallow (10 to 20 inches) Hue: 10YR, 2.5Y, or 5Y Drainage class: Well drained Value: 5 or 6 dry; 4 or 5 moist Permeability: Slow (0.06 to 0.2 inch/hour) Chroma: 1 or 2; 4 or 6 for stains of shale Landform: Sedimentary plains and hills Texture: Clay or silty clay Parent material: Semiconsolidated shale Clay content: 40 to 50 percent Slope range: 3 to 45 percent Electrical conductivity: 0 to 2 mmhos/cm Annual precipitation: 12 to 15 inches Reaction: pH 5.6 to 7.8 Taxonomic Class: Clayey, montmorillonitic, nonacid, C2 horizon frigid, shallow Aridic Ustorthents Hue: 10YR, 2.5Y, or 5Y Value: 5 or 6 dry; 4 or 5 moist Typical Pedon Chroma: 1 to 4 Neldore clay, in an area of Neldore-Rock outcrop Texture: Clay or silty clay complex, 15 to 45 percent slopes, in an area of Clay content: 40 to 60 percent Carter County, Montana—Part I 123

Electrical conductivity: 0 to 4 mmhos/cm 58E—Neldore-Rock outcrop complex, Reaction: pH 5.6 to 7.8 15 to 45 percent slopes Cr horizon Features: The shale fragments are extremely Setting hard or very hard when dry and extremely firm Landform: or very firm when moist. • Neldore—Hills Reaction: pH 5.1 to 7.3 • Rock outcrop—Hills Slope: 15 to 45 percent Mean annual precipitation: 12 to 15 inches 58D—Neldore-Rock outcrop complex, 4 to 15 percent slopes Composition Major Components Setting Neldore and similar soils: 45 percent Rock outcrop: 40 percent Landform: • Neldore—Sedimentary plains and hills Minor Components • Rock outcrop—Hills Volborg and similar soils: 0 to 4 percent Slope: 4 to 15 percent Bascovy and similar soils: 0 to 4 percent Mean annual precipitation: 12 to 15 inches Very shallow clayey soils: 0 to 3 percent Orinoco and similar soils: 0 to 2 percent Composition Vaeda and similar soils: 0 to 2 percent Major Components Major Component Description Neldore and similar soils: 50 percent Rock outcrop: 35 percent Neldore Surface layer texture: Clay Minor Components Depth class: Shallow (10 to 20 inches) Volborg and similar soils: 0 to 4 percent Drainage class: Well drained Bascovy and similar soils: 0 to 4 percent Dominant parent material: Semiconsolidated shale Very shallow clayey soils: 0 to 3 percent residuum Orinoco and similar soils: 0 to 2 percent Native plant cover type: Rangeland Vaeda and similar soils: 0 to 2 percent Flooding: None Major Component Description Available water capacity: Mainly 1.8 inches Neldore Rock outcrop Surface layer texture: Clay Definition: Consolidated shale Depth class: Shallow (10 to 20 inches) Drainage class: Well drained A typical soil description with range in Dominant parent material: Semiconsolidated shale characteristics is included, in alphabetical order, residuum in this section. Native plant cover type: Rangeland Flooding: None Management Available water capacity: Mainly 1.8 inches For management information about this map unit, see appropriate sections in Part II of this publication. Rock outcrop Definition: Consolidated shale 158D—Neldore clay, A typical soil description with range in 4 to 15 percent slopes characteristics is included, in alphabetical order, in this section. Setting Management Landform: Hills For management information about this map unit, Slope: 15 to 35 percent see appropriate sections in Part II of this publication. Mean annual precipitation: 12 to 15 inches 124 Soil Survey

Composition Major Component Description Major Components Surface layer texture: Clay Neldore and similar soils: 85 percent Depth class: Shallow (10 to 20 inches) Drainage class: Well drained Minor Components Dominant parent material: Semiconsolidated shale Volborg and similar soils: 0 to 4 percent residuum Bascovy and similar soils: 0 to 3 percent Native plant cover type: Rangeland Very shallow clayey soils: 0 to 3 percent Flooding: None Vaeda and similar soils: 0 to 2 percent Available water capacity: Mainly 1.8 inches Yawdim and similar soils: 0 to 2 percent Soils that have slopes more than 35 percent: 0 to A typical soil description with range in 1 percent characteristics is included, in alphabetical order, Major Component Description in this section. Surface layer texture: Clay Management Depth class: Shallow (10 to 20 inches) For management information about this map unit, Drainage class: Well drained see appropriate sections in Part II of this publication. Dominant parent material: Semiconsolidated shale residuum Native plant cover type: Rangeland Flooding: None 258D—Neldore-Volborg clays, Available water capacity: Mainly 1.8 inches 4 to 15 percent slopes

A typical soil description with range in Setting characteristics is included, in alphabetical order, Landform: in this section. • Neldore—Sedimentary plains and hills Management • Volborg—Sedimentary plains and hills Slope: For management information about this map unit, • Neldore—4 to 15 percent see appropriate sections in Part II of this publication. • Volborg—4 to 15 percent Mean annual precipitation: 12 to 15 inches 158E—Neldore clay, Composition 15 to 35 percent slopes Major Components Neldore and similar soils: 50 percent Setting Volborg and similar soils: 35 percent Landform: Sedimentary plains and hills Minor Components Slope: 4 to 15 percent Bascovy and similar soils: 0 to 4 percent Mean annual precipitation: 12 to 15 inches Very shallow clayey soils: 0 to 3 percent Composition Areas of rock outcrop: 0 to 3 percent Areas of blowouts: 0 to 3 percent Major Components Yawdim and similar soils: 0 to 2 percent Neldore and similar soils: 85 percent Major Component Description Minor Components Volborg and similar soils: 0 to 4 percent Neldore Bascovy and similar soils: 0 to 3 percent Surface layer texture: Clay Very shallow clayey soils: 0 to 3 percent Depth class: Shallow (10 to 20 inches) Yawdim and similar soils: 0 to 2 percent Drainage class: Well drained Vaeda and similar soils: 0 to 2 percent Dominant parent material: Semiconsolidated shale Soils that have slopes more than 15 percent: 0 to residuum 1 percent Native plant cover type: Rangeland Carter County, Montana—Part I 125

Flooding: None Drainage class: Well drained Available water capacity: Mainly 1.8 inches Dominant parent material: Semiconsolidated shale residuum Volborg Native plant cover type: Rangeland Surface layer texture: Clay Flooding: None Depth class: Shallow (10 to 20 inches) Available water capacity: Mainly 1.8 inches Drainage class: Well drained Dominant parent material: Semiconsolidated shale Bascovy residuum Surface layer texture: Clay Native plant cover type: Rangeland Depth class: Moderately deep (20 to 40 inches) Flooding: None Drainage class: Well drained Available water capacity: Mainly 1.9 inches Dominant parent material: Semiconsolidated shale residuum A typical soil description with range in Native plant cover type: Rangeland characteristics is included, in alphabetical order, Flooding: None in this section. Sodium affected: Sodic within 30 inches Available water capacity: Mainly 5.3 inches Management For management information about this map unit, A typical soil description with range in see appropriate sections in Part II of this publication. characteristics is included, in alphabetical order, in this section. 358D—Neldore-Bascovy clays, Management 4 to 15 percent slopes For management information about this map unit, see appropriate sections in Part II of this publication. Setting Landform: 625E—Neldore clay, warm, • Neldore—Sedimentary plains and hills 3 to 25 percent slopes • Bascovy—Sedimentary plains and hills Position on landform: Setting • Neldore—Shoulders and summits • Bascovy—Backslopes and shoulders Landform: Sedimentary plains and hills Slope: Slope: 3 to 25 percent • Neldore—4 to 15 percent Mean annual precipitation: 12 to 15 inches • Bascovy—4 to 15 percent Composition Mean annual precipitation: 12 to 15 inches Major Components Composition Neldore and similar soils: 85 percent Major Components Minor Components Neldore and similar soils: 45 percent Volborg and similar soils: 0 to 4 percent Bascovy and similar soils: 40 percent Bascovy and similar soils: 0 to 3 percent Minor Components Very shallow clayey soils: 0 to 3 percent Yawdim and similar soils: 0 to 4 percent Vaeda and similar soils: 0 to 2 percent Areas of rock outcrop: 0 to 3 percent Yawdim and similar soils: 0 to 2 percent Orinoco and similar soils: 0 to 3 percent Soils that have slopes more than 25 percent: 0 to Bickerdyke and similar soils: 0 to 2 percent 1 percent Vaeda and similar soils: 0 to 2 percent Major Component Description Very shallow clayey soils: 0 to 1 percent Surface layer texture: Clay Major Component Description Depth class: Shallow (10 to 20 inches) Neldore Drainage class: Well drained Surface layer texture: Clay Dominant parent material: Semiconsolidated shale Depth class: Shallow (10 to 20 inches) residuum 126 Soil Survey

Native plant cover type: Rangeland coarse subangular blocky structure; hard, firm, Flooding: None moderately sticky, moderately plastic; few very Available water capacity: Mainly 1.8 inches fine roots; few very fine pores; few fine masses and seams of lime; violently effervescent; strongly A typical soil description with range in alkaline; clear smooth boundary. characteristics is included, in alphabetical order, Bk2—25 to 35 inches; pale olive (5Y 6/3) sandy clay in this section. loam, olive (5Y 5/3) moist; strong coarse prismatic structure; hard, friable, moderately Management sticky, moderately plastic; few very fine roots; For management information about this map unit, common very fine pores; few fine masses and see appropriate sections in Part II of this publication. seams of lime; violently effervescent; strongly alkaline; clear smooth boundary. BC—35 to 60 inches; pale olive (5Y 6/4) sandy clay Noonan Series loam, olive (5Y 5/4) moist; moderate medium subangular blocky structure; hard, friable, Depth class: Very deep (more than 60 inches) moderately sticky, moderately plastic; few very Drainage class: Well drained fine roots; few very fine pores; disseminated lime; Permeability: Slow (0.06 to 0.2 inch/hour) violently effervescent; strongly alkaline. Landform: Alluvial fans Parent material: Alluvium Range in Characteristics Slope range: 4 to 15 percent Thickness of the mollic epipedon: 7 to 16 inches Annual precipitation: 15 to 17 inches Depth to the Bk horizon: 13 to 30 inches Taxonomic Class: Fine-loamy, mixed Aridic A horizons Natriborolls Value: 3, 4, or 5 dry; 2 or 3 moist Chroma: 2 or 3 Typical Pedon Clay content: 15 to 27 percent Noonan loam, in an area of Shambo-Noonan loams, Reaction: pH 6.1 to 7.8 4 to 15 percent slopes, in an area of rangeland, Btn horizon 1,800 feet south and 2,500 feet west of the northeast Hue: 10YR or 2.5Y corner of sec. 10, T. 3 S., R. 62 S. Value: 3, 4, 5, or 6 dry; 2, 3, or 4 moist A1—0 to 8 inches; dark grayish brown (10YR 4/2) Chroma: 2 to 4 loam, very dark grayish brown (10YR 3/2) moist; Clay content: 27 to 35 percent moderate medium subangular blocky structure; Electrical conductivity: 0 to 2 mmhos/cm slightly hard, very friable, slightly sticky, slightly Sodium adsorption ratio: 13 to 30 plastic; many very fine and fine roots; few fine Reaction: pH 7.4 to 9.0 and common very fine pores; neutral; clear wavy Bk horizons boundary. Hue: 10YR, 2.5Y, or 5Y A2—8 to 11 inches; grayish brown (10YR 5/2) fine Value: 5, 6, or 7 dry; 4, 5, or 6 moist sandy loam, very dark grayish brown (10YR 3/2) Chroma: 2 to 4 moist; moderate thick platy structure; slightly Texture: Loam, clay loam, or sandy clay loam hard, very friable, nonsticky, slightly plastic; Clay content: 20 to 30 percent common very fine roots; few fine and common Electrical conductivity: 0 to 2 mmhos/cm very fine pores; slightly alkaline; abrupt wavy Sodium adsorption ratio: 13 to 30 boundary. Calcium carbonate equivalent: 5 to 15 percent Btn—11 to 16 inches; brown (10YR 5/3) clay loam, Reaction: pH 7.4 to 9.0 dark brown (10YR 3/3) moist; strong coarse columnar structure; very hard, firm, moderately BC horizon sticky, moderately plastic; few very fine roots; few Hue: 2.5Y or 5Y very fine pores; common faint clay films on faces Value: 5, 6, or 7 dry; 4, 5, or 6 moist of peds and in pores; strongly alkaline; clear wavy Chroma: 2 to 4 boundary. Clay content: 20 to 30 percent Bk1—16 to 25 inches; light olive brown (2.5Y 5/4) Electrical conductivity: 2 to 8 mmhos/cm clay loam, olive brown (2.5Y 4/4) moist; strong Sodium adsorption ratio: 13 to 30 Carter County, Montana—Part I 127

Calcium carbonate equivalent: 5 to 10 percent Cr—32 to 60 inches; gray (10YR 5/1) Reaction: pH 7.4 to 9.0 semiconsolidated shale, dark gray (10YR 4/1) moist.

Orinoco Series Range in Characteristics Depth class: Moderately deep (20 to 40 inches) Soil temperature: 41 to 47 degrees F Drainage class: Well drained Depth to the Bky horizon: 6 to 10 inches Permeability: Slow (0.06 to 0.2 inch/hour) Depth to the Cr horizon: 20 to 40 inches Landform: Sedimentary plains and hills Taxonomic note: Map unit 631D is a taxadjunct to Parent material: Semiconsolidated shale the Orinoco series in order to join soils that Slope range: 2 to 15 percent have an average soil temperature greater than Annual precipitation: 12 to 15 inches 47 degrees F. Taxonomic Class: Fine, montmorillonitic A horizon (calcareous), frigid Aridic Ustorthents Value: 5 or 6 dry; 4 or 5 moist Typical Pedon Clay content: 30 to 40 percent Content of rock fragments: 0 to 5 percent pebbles Orinoco silty clay loam, 2 to 8 percent slopes, in an Reaction: pH 7.4 to 8.4 area of rangeland, 2,200 feet north and 1,850 feet east of the southwest corner of sec. 9, T. 9 S., Bw horizon R. 61 E. Value: 5 or 6 dry; 4 or 5 moist Texture: Silty clay loam or silty clay A—0 to 2 inches; light brownish gray (2.5Y 6/2) silty Clay content: 35 to 45 percent clay loam, dark grayish brown (2.5Y 4/2) moist; Electrical conductivity: 4 to 8 mmhos/cm moderate fine granular structure; soft, friable, Sodium adsorption ratio: 5 to 15 moderately sticky, moderately plastic; common Reaction: pH 7.9 to 8.4 very fine roots; disseminated lime; strongly effervescent; slightly alkaline; clear smooth Bky horizons boundary. Hue: 10YR or 2.5Y Bw—2 to 9 inches; grayish brown (2.5Y 5/2) silty clay Value: 5 or 6 dry; 4 or 5 moist loam, dark grayish brown (2.5Y 4/2) moist; Chroma: 1 or 2 moderate medium prismatic structure parting to Texture: Silty clay loam, clay, or silty clay strong fine and medium subangular blocky; hard, Clay content: 35 to 45 percent firm, moderately sticky, moderately plastic; Content of rock fragments: 0 to 5 percent pebbles common very fine roots; common fine pores; Electrical conductivity: 8 to 16 mmhos/cm disseminated lime; strongly effervescent; Sodium adsorption ratio: 15 to 30 moderately alkaline; clear smooth boundary. Calcium carbonate equivalent: 5 to 15 percent Bky1—9 to 22 inches; light brownish gray (2.5Y 6/2) Gypsum content: 1 to 5 percent silty clay loam, dark grayish brown (2.5Y 4/2) Reaction: pH 7.9 to 8.4 moist; moderate medium prismatic structure Cr horizon parting to moderate medium and coarse Electrical conductivity: 8 to 16 mmhos/cm subangular blocky; hard, firm, moderately sticky, Sodium adsorption ratio: 15 to 30 moderately plastic; common very fine roots; Reaction: pH 6.1 to 7.8 common very fine pores; common very fine nests and seams of gypsum crystals; many fine masses of lime; strongly effervescent; moderately alkaline; clear smooth boundary. 53C—Orinoco silty clay loam, Bky2—22 to 32 inches; grayish brown (2.5Y 5/2) silty 2 to 8 percent slopes clay, dark grayish brown (2.5Y 4/2) moist; massive; hard, firm, moderately sticky, Setting moderately plastic; few very fine roots; common very fine pores; many fine gypsum crystals; few Landform: Sedimentary plains fine masses of lime; slightly effervescent; Slope: 2 to 8 percent moderately alkaline; gradual smooth boundary. Mean annual precipitation: 12 to 15 inches 128 Soil Survey

Composition Delpoint and similar soils: 0 to 3 percent Absher and similar soils: 0 to 3 percent Major Components Cabbart and similar soils: 0 to 2 percent Orinoco and similar soils: 85 percent Areas of slickspots: 0 to 1 percent Minor Components Major Component Description Neldore and similar soils: 0 to 5 percent Kobase and similar soils: 0 to 5 percent Orinoco Yawdim and similar soils: 0 to 3 percent Surface layer texture: Silty clay loam Bascovy and similar soils: 0 to 2 percent Depth class: Moderately deep (20 to 40 inches) Drainage class: Well drained Major Component Description Dominant parent material: Semiconsolidated shale Surface layer texture: Silty clay loam residuum Depth class: Moderately deep (20 to 40 inches) Native plant cover type: Rangeland Drainage class: Well drained Flooding: None Dominant parent material: Semiconsolidated shale Salt affected: Saline within 30 inches residuum Sodium affected: Sodic within 30 inches Native plant cover type: Rangeland Available water capacity: Mainly 3.8 inches Flooding: None Salt affected: Saline within 30 inches Yawdim Sodium affected: Sodic within 30 inches Surface layer texture: Silty clay loam Available water capacity: Mainly 3.8 inches Depth class: Shallow (10 to 20 inches) Drainage class: Well drained A typical soil description with range in Dominant parent material: Semiconsolidated shale characteristics is included, in alphabetical order, residuum in this section. Native plant cover type: Rangeland Flooding: None Management Available water capacity: Mainly 2.5 inches For management information about this map unit, see appropriate sections in Part II of this publication. A typical soil description with range in characteristics is included, in alphabetical order, in this section. 153D—Orinoco-Yawdim silty clay loams, 4 to 15 percent slopes Management For management information about this map unit, Setting see appropriate sections in Part II of this publication. Landform: • Orinoco—Sedimentary plains and hills • Yawdim—Sedimentary plains and hills 253D—Orinoco-Weingart complex, Position on landform: 4 to 15 percent slopes • Orinoco—Backslopes • Yawdim—Summits Setting Slope: Landform: • Orinoco—4 to 15 percent • Orinoco—Sedimentary plains and hills • Yawdim—4 to 15 percent • Weingart—Sedimentary plains and hills Mean annual precipitation: 12 to 15 inches Slope: Composition • Orinoco—4 to 15 percent • Weingart—4 to 15 percent Major Components Mean annual precipitation: 12 to 15 inches Orinoco and similar soils: 50 percent Yawdim and similar soils: 35 percent Composition Minor Components Major Components Kobase and similar soils: 0 to 3 percent Orinoco and similar soils: 45 percent Neldore and similar soils: 0 to 3 percent Weingart and similar soils: 40 percent Carter County, Montana—Part I 129

Minor Components Slope: Neldore and similar soils: 0 to 3 percent • Orinoco—4 to 15 percent Cabbart and similar soils: 0 to 3 percent • Yawdim—4 to 15 percent Marvan and similar soils: 0 to 3 percent Mean annual precipitation: 12 to 15 inches Absher and similar soils: 0 to 3 percent Composition Kobase and similar soils: 0 to 2 percent Areas of slickspots: 0 to 1 percent Major Components Orinoco and similar soils: 50 percent Major Component Description Yawdim and similar soils: 35 percent Orinoco Minor Components Surface layer texture: Silty clay loam Neldore and similar soils: 0 to 3 percent Depth class: Moderately deep (20 to 40 inches) Cabbart and similar soils: 0 to 3 percent Drainage class: Well drained Absher and similar soils: 0 to 3 percent Dominant parent material: Semiconsolidated shale Very shallow clayey soils: 0 to 3 percent residuum Kobase and similar soils: 0 to 2 percent Native plant cover type: Rangeland Areas of slickspots: 0 to 1 percent Flooding: None Salt affected: Saline within 30 inches Major Component Description Sodium affected: Sodic within 30 inches Orinoco Available water capacity: Mainly 3.8 inches Surface layer texture: Silty clay loam Depth class: Moderately deep (20 to 40 inches) Weingart Drainage class: Well drained Surface layer texture: Silty clay Dominant parent material: Semiconsolidated shale Depth class: Moderately deep (20 to 40 inches) residuum Drainage class: Well drained Native plant cover type: Rangeland Dominant parent material: Semiconsolidated shale Flooding: None residuum Salt affected: Saline within 30 inches Native plant cover type: Rangeland Sodium affected: Sodic within 30 inches Flooding: None Available water capacity: Mainly 3.8 inches Salt affected: Saline within 30 inches Sodium affected: Sodic within 30 inches Yawdim Available water capacity: Mainly 4.2 inches Surface layer texture: Silty clay loam Depth class: Shallow (10 to 20 inches) A typical soil description with range in Drainage class: Well drained characteristics is included, in alphabetical order, Dominant parent material: Semiconsolidated shale in this section. residuum Management Native plant cover type: Rangeland Flooding: None For management information about this map unit, Available water capacity: Mainly 2.5 inches see appropriate sections in Part II of this publication. A typical soil description with range in characteristics is included, in alphabetical order, 631D—Orinoco-Yawdim silty clay loams, in this section. warm, 4 to 15 percent slopes Management Setting For management information about this map unit, see appropriate sections in Part II of this publication. Landform: • Orinoco—Sedimentary plains and hills • Yawdim—Sedimentary plains and hills Parchin Series Position on landform: • Orinoco—Backslopes Depth class: Moderately deep (20 to 40 inches) • Yawdim—Summits Drainage class: Well drained 130 Soil Survey

Permeability: Slow (0.06 to 0.2 inch/hour) crush to sandy clay loam, brown (10YR 4/3) Landform: Sedimentary plains moist. Parent material: Semiconsolidated, loamy Range in Characteristics sedimentary beds Slope range: 2 to 8 percent Depth to the Bk horizon: 13 to 25 inches Annual precipitation: 12 to 17 inches Depth to the Cr horizon: 20 to 40 inches Other features: Fine threads of gypsum or other salts Taxonomic Class: Fine-loamy, mixed Borollic are present in the lower part of the Btn horizon in Natrargids some pedons. Pedons with sodium adsorption ratios of less than 13 have more exchangeable Typical Pedon magnesium plus sodium than calcium plus exchangeable acidity at pH 8.2. Some pedons Parchin fine sandy loam, in an area of Parchin fine contain few or common threads and nests of sandy loam, 2 to 8 percent slopes, in an area of gypsum and other salts. rangeland, 500 feet south and 40 feet west of the Taxonomic note: The Parchin soil is a taxadjunct to northeast corner of sec. 11, T. 5 S., R. 62 E. the series. It classifies as Fine-loamy, mixed Typic Natriboralfs. Map units 116C and 231D are A—0 to 6 inches; brown (10YR 5/3) fine sandy loam, taxadjuncts to the Parchin series. These soils dark grayish brown (10YR 4/2) moist; weak fine receive more precipitation than is normal for the granular structure; soft, very friable, nonsticky, series, but this does not affect the use and nonplastic; many very fine roots; neutral; abrupt management. smooth boundary. A horizon E—6 to 11 inches; pale brown (10YR 6/3) fine sandy Hue: 10YR or 2.5Y loam, dark grayish brown (10YR 4/2) moist; weak Value: 5 or 6 dry; 3 or 4 moist medium subangular blocky structure; soft, very Chroma: 2 or 3 friable, nonsticky, nonplastic; common very fine Clay content: 10 to 20 percent roots; few very fine and fine pores; neutral; abrupt Reaction: pH 5.6 to 7.3 smooth boundary. Btn—11 to 17 inches; brown (10YR 5/3) sandy clay E horizon loam, brown (10YR 4/3) moist; moderate coarse Hue: 10YR or 2.5Y columnar structure parting to strong fine and Value: 5, 6, or 7 dry; 4, 5, or 6 moist medium subangular blocky; very hard, firm, Chroma: 2 or 3 slightly sticky, moderately plastic; few very fine Clay content: 10 to 20 percent and fine roots; few fine and common very fine Reaction: pH 5.6 to 7.3 pores; many distinct clay films on faces of peds Btn horizon and in pores; moderately alkaline; gradual wavy Hue: 10YR or 2.5Y boundary. Value: 5 or 6 dry; 4 or 5 moist Btkn—17 to 22 inches; brown (10YR 5/3) clay loam, Chroma: 2 or 3 dark brown (10YR 3/3) moist; moderate coarse Texture: Clay loam, sandy clay loam, or loam prismatic structure parting to strong medium Clay content: 25 to 34 percent subangular blocky; very hard, very firm, sticky Electrical conductivity: 2 to 8 mmhos/cm and plastic; few very fine and fine roots; few very Sodium adsorption ratio: 13 to 20 fine and fine pores; few faint clay films on faces of Reaction: pH 7.9 to 9.0 peds and common distinct clay films in pores; many fine and medium masses of lime; Btkn and Bk horizons moderately alkaline; gradual wavy boundary. Hue: 10YR, 2.5Y, or 5Y Bk—22 to 28 inches; pale brown (10YR 6/3) clay Value: 5 or 6 dry; 3 to 5 moist loam, brown (10YR 5/3) moist; massive, very Chroma: 2 or 3 hard, moderately sticky, moderately plastic; many Texture: Clay loam, sandy clay loam, or loam fine and medium masses of lime; strongly Clay content: 20 to 30 percent effervescent; strongly alkaline; clear smooth Electrical conductivity: 2 to 8 mmhos/cm boundary. Sodium adsorption ratio: 13 to 20 Cr—28 to 60 inches; brown (10YR 5/3) Calcium carbonate equivalent: 5 to 15 percent semiconsolidated loamy sedimentary beds that Reaction: pH 7.9 to 9.0 Carter County, Montana—Part I 131

21C—Parchin fine sandy loam, Composition 2 to 8 percent slopes Major Components Parchin and similar soils: 50 percent Setting Bullock and similar soils: 35 percent Landform: Sedimentary plains Minor Components Slope: 2 to 8 percent Delpoint and similar soils: 0 to 4 percent Mean annual precipitation: 12 to 15 inches Cabbart and similar soils: 0 to 3 percent Bascovy and similar soils: 0 to 3 percent Composition Soils with darker colored surface layers: 0 to Major Components 3 percent Parchin and similar soils: 85 percent Soils that have slopes more than 8 percent: 0 to 2 percent Minor Components Cabbart and similar soils: 0 to 3 percent Major Component Description Yamacall and similar soils: 0 to 3 percent Parchin Busby and similar soils: 0 to 3 percent Surface layer texture: Fine sandy loam Kobase and similar soils: 0 to 3 percent Depth class: Moderately deep (20 to 40 inches) Areas of slickspots: 0 to 3 percent Drainage class: Well drained Major Component Description Dominant parent material: Semiconsolidated, loamy sedimentary beds Surface layer texture: Fine sandy loam Native plant cover type: Rangeland Depth class: Moderately deep (20 to 40 inches) Flooding: None Drainage class: Well drained Sodium affected: Sodic within 30 inches Dominant parent material: Semiconsolidated, loamy Available water capacity: Mainly 4.0 inches sedimentary beds Native plant cover type: Rangeland Bullock Flooding: None Surface layer texture: Clay loam Sodium affected: Sodic within 30 inches Depth class: Moderately deep (20 to 40 inches) Available water capacity: Mainly 4.1 inches Drainage class: Well drained Dominant parent material: Semiconsolidated, loamy A typical soil description with range in sedimentary beds characteristics is included, in alphabetical order, Native plant cover type: Rangeland in this section. Flooding: None Management Salt affected: Saline within 30 inches Sodium affected: Sodic within 30 inches For management information about this map unit, Available water capacity: Mainly 4.2 inches see appropriate sections in Part II of this publication. A typical soil description with range in 121C—Parchin-Bullock complex, characteristics is included, in alphabetical order, 2 to 8 percent slopes in this section. Management Setting For management information about this map unit, Landform: see appropriate sections in Part II of this publication. • Parchin—Sedimentary plains • Bullock—Sedimentary plains Slope: Parshall Series • Parchin—2 to 8 percent • Bullock—2 to 8 percent Depth class: Very deep (more than 60 inches) Mean annual precipitation: 12 to 15 inches Drainage class: Well drained 132 Soil Survey

Permeability: Moderately rapid (2.0 to 6.0 inches/ nonsticky, slightly plastic; few very fine roots; few hour) very fine pores; few fine seams and masses of Landform: Alluvial fans, stream terraces, and lime; violently effervescent; moderately alkaline. drainageways Range in Characteristics Parent material: Alluvium Slope range: 0 to 15 percent Soil temperature: 42 to 47 degrees F Annual precipitation: 15 to 17 inches Thickness of the mollic epipedon: 17 to 40 inches Depth to the Bk horizon: 24 to 60 inches Taxonomic Class: Coarse-loamy, mixed Pachic Other features: Some pedons do not have buried Haploborolls horizons (Ab or Bkb horizons). Typical Pedon A horizons Value: 2, 3, 4, or 5 dry; 2 or 3 moist Parshall fine sandy loam, in an area of Parshall- Chroma: 2 or 3 Cohagen fine sandy loams, 4 to 15 percent slopes, in Texture: Fine sandy loam or sandy loam an area of rangeland, 1,400 feet south and 300 feet Clay content: 10 to 18 percent west of the northeast corner of sec. 17, T. 4 S., Reaction: pH 6.6 to 7.3 R. 60 E. Bw horizon A1—0 to 3 inches; dark grayish brown (10YR 4/2) Hue: 10YR or 2.5Y fine sandy loam, very dark brown (10YR 2/2) Value: 3, 4, 5, or 6 dry; 2, 3, 4, or 5 moist moist; weak thin platy structure; soft, very friable, Chroma: 2 to 4 nonsticky, slightly plastic; many very fine and fine Texture: Fine sandy loam, sandy loam, loam, or roots; few very fine pores; neutral; abrupt smooth loamy fine sand boundary. Clay content: 10 to 18 percent A2—3 to 7 inches; dark brown (10YR 4/3) fine sandy Reaction: pH 6.6 to 7.8 loam, very dark grayish brown (10YR 3/2) moist; moderate fine subangular blocky structure; soft, Bk horizon very friable, nonsticky, slightly plastic; common Hue: 10YR or 2.5Y fine and many very fine roots; few very fine and Value: 5 or 6 dry; 4 or 5 moist fine pores; neutral; clear smooth boundary. Chroma: 2 to 4 Bw—7 to 32 inches; brown (10YR 5/3) fine sandy Texture: Fine sandy loam, loamy fine sand, or loam, very dark grayish brown (10YR 3/2) moist; loamy sand moderate medium subangular blocky structure; Clay content: 5 to 18 percent soft, very friable, nonsticky, slightly plastic; few Calcium carbonate equivalent: 5 to 10 percent very fine and common fine roots; few very fine Reaction: pH 7.4 to 8.4 pores; neutral; abrupt smooth boundary. Ab and Bkb horizons Bk—32 to 42 inches; light brownish gray (10YR 6/2) Clay content: 5 to 18 percent fine sandy loam, dark grayish brown (10YR 4/2) Reaction: pH 7.4 to 8.4 moist; moderate coarse subangular blocky structure; soft, very friable, nonsticky, slightly plastic; few very fine roots; few very fine pores; 36A—Parshall sandy loam, few fine masses of lime; strongly effervescent; 0 to 4 percent slopes moderately alkaline; abrupt smooth boundary. Ab—42 to 47 inches; light brownish gray (2.5Y 6/2) Setting fine sandy loam, very dark grayish brown (2.5Y 3/2) moist; moderate coarse subangular blocky Landform: Alluvial fans, stream terraces, and structure; soft, very friable, nonsticky, slightly drainageways plastic; few very fine roots; few very fine pores; Slope: 0 to 4 percent disseminated lime, strongly effervescent; Mean annual precipitation: 15 to 17 inches moderately alkaline; clear smooth boundary. Composition Bkb—47 to 60 inches; light gray (2.5Y 7/2) fine sandy loam, light olive brown (2.5Y 5/2) moist; weak Major Components medium platy structure; soft, very friable, Parshall and similar soils: 85 percent Carter County, Montana—Part I 133

Minor Components Flooding: None Chinook and similar soils: 0 to 4 percent Available water capacity: Mainly 7.9 inches Assinniboine and similar soils: 0 to 3 percent Delpoint and similar soils: 0 to 3 percent A typical soil description with range in Marmarth and similar soils: 0 to 3 percent characteristics is included, in alphabetical order, Soils with lighter colored surface layers: 0 to in this section. 2 percent Management Major Component Description For management information about this map unit, Surface layer texture: Sandy loam see appropriate sections in Part II of this publication. Depth class: Very deep (more than 60 inches) Drainage class: Well drained Dominant parent material: Alluvium 136D—Parshall-Cohagen fine sandy Native plant cover type: Rangeland loams, 4 to 15 percent slopes Flooding: None Available water capacity: Mainly 7.9 inches Setting A typical soil description with range in Landform: characteristics is included, in alphabetical order, • Parshall—Alluvial fans, stream terraces, and in this section. drainageways • Cohagen—Sedimentary plains and hills Management Slope: For management information about this map unit, • Parshall—4 to 15 percent see appropriate sections in Part II of this publication. • Cohagen—4 to 15 percent Mean annual precipitation: 15 to 17 inches Composition 36D—Parshall fine sandy loam, 4 to 15 percent slopes Major Components Parshall and similar soils: 50 percent Cohagen and similar soils: 35 percent Setting Minor Components Landform: Alluvial fans, stream terraces, and Delpoint and similar soils: 0 to 4 percent drainageways Marmarth and similar soils: 0 to 3 percent Slope: 4 to 15 percent Chinook and similar soils: 0 to 3 percent Mean annual precipitation: 15 to 17 inches Shallow soils with channers: 0 to 3 percent Composition Soils with flagstones: 0 to 2 percent Major Components Major Component Description Parshall and similar soils: 85 percent Parshall Minor Components Surface layer texture: Fine sandy loam Chinook and similar soils: 0 to 4 percent Depth class: Very deep (more than 60 inches) Assinniboine and similar soils: 0 to 3 percent Drainage class: Well drained Delpoint and similar soils: 0 to 3 percent Dominant parent material: Alluvium Marmarth and similar soils: 0 to 3 percent Native plant cover type: Rangeland Soils with lighter colored surface layers: 0 to Flooding: None 2 percent Available water capacity: Mainly 7.9 inches Major Component Description Cohagen Surface layer texture: Fine sandy loam Surface layer texture: Fine sandy loam Depth class: Very deep (more than 60 inches) Depth class: Shallow (10 to 20 inches) Drainage class: Well drained Drainage class: Well drained Dominant parent material: Alluvium Dominant parent material: Sandstone residuum Native plant cover type: Rangeland Native plant cover type: Rangeland 134 Soil Survey

Flooding: None loose, nonsticky, nonplastic; 10 percent pebbles; Available water capacity: Mainly 1.3 inches neutral. Range in Characteristics A typical soil description with range in characteristics is included, in alphabetical order, Soil temperature: 42 to 47 degrees F in this section. Thickness of the mollic epipedon: 7 to 10 inches Depth to the 2C horizon: 10 to 20 inches Management A horizon For management information about this map unit, Hue: 7.5YR, 10YR, or 2.5Y see appropriate sections in Part II of this publication. Value: 4 or 5 dry; 2 or 3 moist Chroma: 2 or 3 Clay content: 8 to 14 percent Prego Series Content of rock fragments: 0 to 15 percent pebbles Depth class: Very deep (more than 60 inches) Reaction: pH 6.1 to 7.3 Drainage class: Well drained Permeability: Moderately rapid (2.0 to 6.0 inches/ Bt horizons hour) Hue: 7.5YR, 10YR, or 2.5Y Landform: Relict stream terraces Value: 4, 5, or 6 dry; 3, 4, or 5 moist Parent material: Alluvium Chroma: 2 to 4 Slope range: 2 to 15 percent Texture: Sandy loam or fine sandy loam Annual precipitation: 12 to 15 inches Clay content: 14 to 18 Content of rock fragments: 0 to 15 percent Taxonomic Class: Coarse-loamy, mixed Aridic pebbles Argiborolls Reaction: pH 6.1 to 7.3 Typical Pedon 2C horizon Hue: 10YR or 2.5Y Prego sandy loam, 2 to 15 percent slopes, in an area Value: 4, 5, or 6 dry; 4 or 5 moist of rangeland, 1,300 feet south and 1,400 feet west of Chroma: 3 or 4 the northeast corner of sec. 7, T. 1 N., R. 57 E. Texture: Sand or loamy sand A—0 to 5 inches; grayish brown (10YR 5/2) sandy Clay content: 1 to 8 percent loam, very dark grayish brown (10YR 3/2) moist; Content of rock fragments: 5 to 35 percent weak fine granular structure; soft, very friable, pebbles nonsticky, nonplastic; few fine and many very fine Reaction: pH 6.1 to 7.3 roots; slightly acid; clear smooth boundary. Bt1—5 to 10 inches; brown (10YR 5/3) sandy loam, dark brown (10YR 3/3) moist; weak coarse 48D—Prego sandy loam, subangular blocky structure parting to moderate 2 to 15 percent slopes fine and medium subangular blocky; slightly hard, friable, slightly sticky, slightly plastic; many very Setting fine roots; few distinct clay bridges between Landform: Relict stream terraces mineral grains; neutral; clear smooth boundary. Slope: 2 to 15 percent Bt2—10 to 16 inches; yellowish brown (10YR 5/4) Mean annual precipitation: 12 to 15 inches sandy loam, dark yellowish brown (10YR 4/4) moist; moderate medium subangular blocky Composition structure parting to moderate fine subangular Major Components blocky; slightly hard, friable, slightly sticky, slightly Prego and similar soils: 85 percent plastic; few very fine roots; few faint clay films on faces of peds and clay bridges between mineral Minor Components grains; neutral; abrupt smooth boundary. Eapa and similar soils: 0 to 3 percent 2C—16 to 60 inches; light olive brown (2.5Y 5/4) Busby and similar soils: 0 to 3 percent sand; olive brown (2.5Y 4/4) moist; single grain; Delpoint and similar soils: 0 to 3 percent Carter County, Montana—Part I 135

Soils with gravelly surface layers: 0 to 2 percent Bt—8 to 19 inches; light brownish gray, (10YR 6/2) Soils with darker colored surface layers: 0 to clay loam, dark grayish brown (10YR 4/2) moist; 2 percent strong medium and coarse prismatic structure Soils that have slopes more than 15 percent: 0 to parting to strong fine and medium subangular 2 percent blocky; hard, firm, moderately sticky, moderately plastic; few medium and common very fine and Major Component Description fine roots; common very fine and fine pores; few Surface layer texture: Sandy loam faint clay films on faces of peds and in pores; Depth class: Very deep (more than 60 inches) 15 percent soft coarse fragments; slightly Drainage class: Well drained alkaline; gradual wavy boundary. Dominant parent material: Alluvium Bk—19 to 31 inches; light gray (2.5Y 7/2) loam, Native plant cover type: Rangeland grayish brown (2.5Y 5/2) moist; moderate fine Flooding: None and medium subangular blocky structure; hard, Available water capacity: Mainly 3.5 inches friable, slightly sticky, slightly plastic; common very fine and fine roots; common very fine pores; A typical soil description with range in 20 percent soft coarse fragments; common fine characteristics is included, in alphabetical order, seams and masses of lime; violently effervescent; in this section. moderately alkaline; clear wavy boundary. Cr—31 to 60 inches; white (2.5Y 8/0) Management semiconsolidated loamy sedimentary beds that For management information about this map unit, crush to a loam, light gray (2.5Y 7/2) moist. see appropriate sections in Part II of this publication. Range in Characteristics Reeder Series Thickness of the mollic epipedon: 7 to 16 inches Depth to the Bk horizon: 11 to 26 inches Depth class: Moderately deep (20 to 40 inches) Depth to the Cr horizon: 20 to 40 inches Drainage class: Well drained A horizon Permeability: Moderate (0.6 to 2.0 inches/hour) Hue: 10YR or 2.5Y Landform: Sedimentary plains and hills Value: 3, 4, or 5 dry; 2 or 3 moist Parent material: Semiconsolidated, loamy Chroma: 2 or 3 sedimentary beds Clay content: 15 to 27 percent Slope range: 1 to 35 percent Reaction: pH 6.1 to 7.3 Annual precipitation: 15 to 17 inches Bt horizon Taxonomic Class: Fine-loamy, mixed Typic Hue: 7.5YR, 10YR, or 2.5Y Argiborolls Value: 4, 5, or 6 dry; 3, 4, or 5 moist Chroma: 2 to 4 Typical Pedon Texture: Loam, sandy clay loam, or clay loam Reeder loam, in an area of Belltower-Reeder-Vebar Clay content: 18 to 35 percent complex, 4 to 15 percent slopes, in an area of Reaction: pH 6.6 to 8.4 forestland, 1,700 feet north and 2,200 feet west of the Bk horizon southeast corner of sec. 34, T. 2 S., R. 61 E. Hue: 10YR, 2.5Y, or 5Y Oi—1 inch to 0; slightly decomposed forest litter. Value: 5, 6, 7, or 8 dry; 4, 5, or 6 moist A—0 to 8 inches; dark grayish brown (10YR 4/2) Chroma: 2 to 4 loam, very dark brown (10YR 2/2) moist; Texture: Loam, silt loam, silty clay loam, clay moderate fine and medium subangular blocky loam, or sandy clay loam structure; slightly hard, very friable, slightly sticky, Clay content: 15 to 30 percent slightly plastic; few medium and common very Content of soft rock fragments: 35 to 60 percent fine and fine roots; common very fine pores; Calcium carbonate equivalent: 5 to 15 percent neutral; clear smooth boundary. Reaction: pH 7.4 to 8.4 136 Soil Survey

42C—Reeder loam, 2 to 8 percent slopes Composition Major Components Setting Reeder and similar soils: 55 percent Cabba and similar soils: 30 percent Landform: Sedimentary plains Slope: 2 to 8 percent Minor Components Mean annual precipitation: 15 to 17 inches Dast and similar soils: 0 to 4 percent Very deep loamy soils: 0 to 4 percent Composition Very shallow loamy soils: 0 to 3 percent Major Components Moderately saline soils: 0 to 2 percent Reeder and similar soils: 85 percent Soils that have slopes less than 4 percent: 0 to 2 percent Minor Components Cabba and similar soils: 0 to 4 percent Major Component Description Very deep loamy soils: 0 to 3 percent Reeder Moderately saline soils: 0 to 3 percent Surface layer texture: Loam Soils that are calcareous throughout: 0 to 3 percent Depth class: Moderately deep (20 to 40 inches) Soils that have slopes more than 8 percent: 0 to Drainage class: Well drained 2 percent Dominant parent material: Semiconsolidated, loamy Major Component Description sedimentary beds Native plant cover type: Rangeland Surface layer texture: Loam Flooding: None Depth class: Moderately deep (20 to 40 inches) Available water capacity: Mainly 5.2 inches Drainage class: Well drained Dominant parent material: Semiconsolidated, loamy Cabba sedimentary beds Surface layer texture: Loam Native plant cover type: Rangeland Depth class: Shallow (10 to 20 inches) Flooding: None Drainage class: Well drained Available water capacity: Mainly 5.2 inches Dominant parent material: Semiconsolidated, loamy sedimentary beds A typical soil description with range in Native plant cover type: Rangeland characteristics is included, in alphabetical order, Flooding: None in this section. Available water capacity: Mainly 2.6 inches Management A typical soil description with range in For management information about this map unit, characteristics is included, in alphabetical order, see appropriate sections in Part II of this publication. in this section. Management 142D—Reeder-Cabba loams, For management information about this map unit, 4 to 15 percent slopes see appropriate sections in Part II of this publication.

Setting 242D—Reeder-Dast complex, Landform: 4 to 15 percent slopes • Reeder—Sedimentary plains and hills • Cabba—Sedimentary plains and hills Setting Position on landform: • Reeder—Backslopes and footslopes Landform: • Cabba—Shoulders and summits • Reeder—Sedimentary plains and hills Slope: • Dast—Sedimentary plains and hills • Reeder—4 to 15 percent Position on landform: • Cabba—4 to 15 percent • Reeder—Backslopes and shoulders Mean annual precipitation: 15 to 17 inches • Dast—Shoulders and summits Carter County, Montana—Part I 137

Slope: Parent material: Hard sandstone • Reeder—4 to 15 percent Slope range: 2 to 45 percent • Dast—4 to 15 percent Annual precipitation: 12 to 17 inches Mean annual precipitation: 15 to 17 inches Taxonomic Class: Loamy-skeletal, mixed Composition (calcareous), frigid Lithic Ustic Torriorthents Major Components Typical Pedon Reeder and similar soils: 45 percent Dast and similar soils: 40 percent Rentsac sandy loam, in an area of Rentsac-Twilight- Rock outcrop complex, 15 to 45 percent slopes, in an Minor Components area of rangeland, 1,600 feet south and 1,500 feet Very deep loamy soils: 0 to 4 percent west of the northeast corner of sec. 2, T. 1 S., R. 61 E. Cabba and similar soils: 0 to 4 percent Moderately deep clayey soils: 0 to 4 percent A—0 to 4 inches; brown (10YR 5/3) sandy loam, Soils that have slopes less than 4 percent: 0 to brown (10YR 4/3) moist; moderate fine granular 3 percent structure; soft, very friable, nonsticky, nonplastic; common very fine and fine roots; disseminated Major Component Description lime; strongly effervescent; slightly alkaline; clear Reeder smooth boundary. Surface layer texture: Loam Bk—4 to 16 inches; brown (10YR 5/3) very channery Depth class: Moderately deep (20 to 40 inches) sandy loam, brown (10YR 4/3) moist; weak Drainage class: Well drained medium subangular blocky structure; soft, very Dominant parent material: Semiconsolidated, loamy friable, nonsticky, nonplastic; few very fine roots; sedimentary beds few very fine pores; 55 percent channers; Native plant cover type: Rangeland common fine and medium masses of lime; Flooding: None common faint lime coats on undersides of Available water capacity: Mainly 5.2 inches channers; violently effervescent; moderately alkaline. Dast R—16 to 60 inches; hard sandstone. Surface layer texture: Sandy loam Depth class: Moderately deep (20 to 40 inches) Range in Characteristics Drainage class: Well drained Soil temperature: 42 to 47 degrees F Dominant parent material: Semiconsolidated, sandy Depth to the R horizon: 10 to 20 inches sedimentary beds Native plant cover type: Forestland A horizon Flooding: None Hue: 7.5YR, 10YR, or 2.5Y Available water capacity: Mainly 3.6 inches Value: 5 or 6 dry; 3 or 4 moist Chroma: 2 to 4 A typical soil description with range in Clay content: 7 to 18 percent characteristics is included, in alphabetical order, Content of rock fragments: 0 to 15 percent in this section. channers Reaction: pH 6.6 to 8.4 Management Bk horizon For management information about this map unit, Hue: 7.5YR, 10YR, or 2.5Y see appropriate sections in Part II of this publication. Value: 5, 6, or 7 dry; 4 or 5 moist Chroma: 2 to 4 Rentsac Series Texture: Loam, sandy loam, or fine sandy loam Clay content: 7 to 18 percent Depth class: Shallow (10 to 20 inches) Content of rock fragments: 35 to 70 percent Drainage class: Well drained pebbles, channers, and flagstones Permeability: Moderate (0.6 to 2.0 inches/hour) Calcium carbonate equivalent: 5 to 15 percent Landform: Bedrock-floored plains and hills Reaction: pH 7.4 to 8.4 138 Soil Survey

99F—Rentsac-Twilight-Rock outcrop Management complex, 15 to 45 percent slopes For management information about this map unit, see appropriate sections in Part II of this publication. Setting Landform: Ridge Series • Rentsac—Hills • Twilight—Hills Depth class: Shallow (10 to 20 inches) • Rock outcrop—Hills Drainage class: Well drained Slope: Permeability: Moderately rapid (2.0 to 6.0 inches/ • Rentsac—15 to 45 percent hour) • Twilight—15 to 45 percent Landform: Hills Mean annual precipitation: 12 to 15 inches Parent material: Semiconsolidated, sandy sedimentary beds Composition Slope range: 8 to 65 percent Major Components Annual precipitation: 15 to 17 inches Rentsac and similar soils: 35 percent Twilight and similar soils: 30 percent Taxonomic Class: Loamy, mixed, frigid, shallow Rock outcrop: 20 percent Typic Ustochrepts Minor Components Typical Pedon Cabbart and similar soils: 0 to 4 percent Ridge sandy loam, in an area of Broadus-Ridge- Yamacall and similar soils: 0 to 4 percent Reeder complex, 8 to 25 percent slopes, in an area of Blacksheep and similar soils: 0 to 4 percent forestland, 2,500 feet north and 1,500 feet west of the Very shallow loamy soils: 0 to 3 percent southeast corner of sec. 18, T. 8 S., R. 55 E. Major Component Description Oi—1/2 inch to 0; slightly decomposed forest litter. Rentsac A—0 to 2 inches; brown (10YR 5/3) sandy loam, dark Surface layer texture: Sandy loam grayish brown (10YR 4/2) moist; weak fine Depth class: Shallow (10 to 20 inches) granular structure; loose, very friable, nonsticky, Drainage class: Well drained nonplastic; many fine roots; many very fine and Dominant parent material: Sandstone residuum fine pores; disseminated lime; slightly Native plant cover type: Rangeland effervescent; slightly alkaline; clear smooth Flooding: None boundary. Available water capacity: Mainly 1.4 inches Bw1—2 to 6 inches; pale brown (10YR 6/3) sandy loam, dark grayish brown (10YR 4/2) moist; weak Twilight medium subangular blocky structure; soft, friable, Surface layer texture: Fine sandy loam nonsticky, nonplastic; many fine roots; few fine Depth class: Moderately deep (20 to 40 inches) and many very fine pores; disseminated lime; Drainage class: Well drained strongly effervescent; moderately alkaline; clear Dominant parent material: Semiconsolidated, sandy smooth boundary. sedimentary beds Bw2—6 to 12 inches; pale brown (10YR 6/3) sandy Native plant cover type: Rangeland loam, grayish brown (2.5Y 5/2) moist; moderate Flooding: None medium subangular blocky structure; soft, friable, Available water capacity: Mainly 4.2 inches nonsticky, nonplastic; many fine roots; few fine and common very fine pores; disseminated lime; Rock outcrop strongly effervescent; moderately alkaline; clear Definition: Hard sandstone smooth boundary. Bk—12 to 16 inches; light gray (2.5Y 7/2) sandy A typical soil description with range in loam, grayish brown (2.5Y 5/2) moist; massive; characteristics is included, in alphabetical order, soft, friable, nonsticky, nonplastic; common fine in this section. roots; few very fine masses and threads of lime; Carter County, Montana—Part I 139

violently effervescent; moderately alkaline; clear Major Component Description smooth boundary. Definition: Hard calcareous sandstone Cr—16 to 60 inches; light gray (2.5Y 7/2) semiconsolidated, sandy sedimentary beds that crush to loamy sand, grayish brown (2.5Y 5/2) 177E—Rock outcrop-Moyerson complex, moist; common fine roots in cracks; disseminated 15 to 50 percent slopes lime; violently effervescent; moderately alkaline. Setting Range in Characteristics Landform: Soil temperature: 42 to 47 degrees F • Rock outcrop—Hills Depth to the Bk horizon: 10 to 16 inches • Moyerson—Hills Depth to the Cr horizon: 12 to 20 inches Slope: • Moyerson—15 to 50 percent A horizon Mean annual precipitation: 12 to 15 inches Value: 4, 5, or 6 dry; 3, 4, or 5 moist Chroma: 2 to 4 Composition Clay content: 5 to 20 percent Major Components Reaction: pH 7.4 to 7.8 Rock outcrop: 55 percent Bw horizons Moyerson and similar soils: 30 percent Hue: 10YR or 2.5Y Minor Components Value: 5, 6, or 7 dry; 4 or 5 moist Very shallow clayey soils: 0 to 4 percent Chroma: 2 to 4 Strongly saline soils: 0 to 4 percent Texture: Sandy loam or loam Neldore and similar soils: 0 to 4 percent Clay content: 5 to 20 percent Yawdim and similar soils: 0 to 3 percent Reaction: pH 7.4 to 8.4 Major Component Description Bk horizon Hue: 10YR, 2.5Y, or 5Y Rock outcrop Value: 6 or 7 dry; 4, 5, or 6 moist Definition: Consolidated sandstone and shale Chroma: 2 to 4 Texture: Sandy loam or loam Moyerson Clay content: 5 to 20 percent Surface layer texture: Silty clay loam Calcium carbonate equivalent: 5 to 15 percent Depth class: Shallow (10 to 20 inches) Reaction: pH 7.4 to 8.4 Drainage class: Well drained Dominant parent material: Semiconsolidated shale Cr horizon residuum Reaction: pH 7.4 to 8.4 Native plant cover type: Rangeland Flooding: None Salt affected: Saline within 30 inches 13E—Rock outcrop Available water capacity: Mainly 1.8 inches

Setting A typical soil description with range in characteristics is included, in alphabetical order, Landform: Escarpments in this section. Mean annual precipitation: 12 to 15 inches Management Composition Major Components For management information about this map unit, Rock outcrop: 85 percent see appropriate sections in Part II of this publication. Minor Components Blacksheep and similar soils: 0 to 4 percent Ryell Series Cabbart and similar soils: 0 to 4 percent Very shallow loamy soils: 0 to 4 percent Depth class: Very deep (more than 60 inches) Very shallow clayey soils: 0 to 3 percent Drainage class: Well drained 140 Soil Survey

Permeability: Moderate (0.6 to 2.0 inches/hour) above Chroma: 2 or 3 the 2C3 horizon; rapid (6.0 to 20.0 inches/hour) in Clay content: 10 to 20 percent the 2C3 horizon Electrical conductivity: 0 to 2 mmhos/cm Landform: Flood plains Reaction: pH 7.4 to 8.4 Parent material: Alluvium C1 and C2 horizons Slope range: 0 to 4 percent Hue: 10YR or 2.5Y Annual precipitation: 12 to 15 inches Value: 5 or 6 dry; 4 or 5 moist Chroma: 2 to 4 Taxonomic Class: Coarse-loamy over sandy or Texture: Very fine sandy loam, loamy very fine sandy skeletal, mixed (calcareous), frigid Aridic sand, or loam Ustifluvents Clay content: 10 to 18 percent Typical Pedon Content of rock fragments: 0 to 5 percent pebbles Electrical conductivity: 0 to 2 mmhos/cm Ryell fine sandy loam, in an area of Hanly-Ryell fine Reaction: pH 7.4 to 8.4 sandy loams, 0 to 4 percent slopes, in an area of rangeland, 1,600 feet south and 300 feet west of the 2C3 horizon northeast corner of sec. 26, T. 1 N., R. 60 E. Hue: 10YR, 2.5Y, or 5Y Value: 5 or 6 dry; 4 or 5 moist A—0 to 10 inches; light brownish gray (2.5Y 6/2) fine Chroma: 2 or 3 sandy loam, dark grayish brown (2.5Y 4/2) moist; Texture: Sand or loamy sand weak coarse subangular blocky structure; soft, Clay content: 0 to 10 percent very friable, slightly sticky, slightly plastic; Content of rock fragments: 35 to 70 percent—0 to common fine and many very fine roots; few very 15 percent cobbles; 35 to 55 percent pebbles fine and fine pores; slightly alkaline; clear smooth Electrical conductivity: 0 to 2 mmhos/cm boundary. Reaction: pH 7.4 to 8.4 C1—10 to 21 inches; grayish brown (2.5Y 5/2) loam, dark grayish brown (2.5Y 4/2) moist; weak coarse subangular blocky structure; loose, very friable, Shambo Series slightly sticky, slightly plastic; common very fine and fine roots; few very fine pores; 5 percent Depth class: Very deep (more than 60 inches) pebbles; few thin strata of sandy loam; Drainage class: Well drained disseminated lime; strongly effervescent; slightly Permeability: Moderate (0.6 to 2.0 inches/hour) alkaline; clear smooth boundary. Landform: Alluvial fans, sedimentary plains, and hills C2—21 to 31 inches; grayish brown (2.5Y 5/2) loam, Parent material: Alluvium dark grayish brown (2.5Y 4/2) moist; massive; Slope range: 4 to 15 percent soft, very friable, nonsticky, nonplastic; few very Annual precipitation: 15 to 17 inches fine roots; few very fine pores; 5 percent pebbles; few thin strata of sandy loam; disseminated lime; Taxonomic Class: Fine-loamy, mixed Typic strongly effervescent; slightly alkaline; clear Haploborolls smooth boundary. Typical Pedon 2C3—31 to 60 inches; grayish brown (2.5Y 5/2) stratified very gravelly loamy sand and very Shambo loam, in an area of Shambo-Mowbray- gravelly sand, dark grayish brown (2.5Y 4/2) Parchin complex, 4 to 25 percent slopes, in an area moist; single grain; loose, nonsticky, nonplastic; of rangeland, 2,300 feet south and 2,300 feet east of few very fine roots; 40 percent pebbles and the northwest corner of sec. 9, T. 3 S., R. 62 E. 10 percent cobbles; disseminated lime; slightly A—0 to 5 inches; dark grayish brown (10YR 4/2) effervescent; slightly alkaline. loam, very dark grayish brown (10YR 3/2) moist; Range in Characteristics moderate fine subangular blocky structure; slightly hard, very friable, slightly sticky, slightly Soil temperature: 40 to 47 degrees F plastic; many very fine and fine roots; common Depth to the 2C3 horizon: 18 to 36 inches very fine pores; neutral; clear smooth boundary. A horizon Bw1—5 to 14 inches; dark brown (10YR 4/3) loam, Hue: 10YR or 2.5Y very dark grayish brown (10YR 3/2) moist; Value: 5 or 6 dry; 4 or 5 moist moderate coarse subangular blocky structure; Carter County, Montana—Part I 141

slightly hard, friable, slightly sticky, slightly plastic; 131C—Shambo-Noonan loams, common very fine and fine roots; few fine and 4 to 15 percent slopes common very fine pores; neutral; clear smooth boundary. Setting Bw2—14 to 23 inches; light olive brown (2.5Y 5/4) loam, olive brown (2.5Y 4/4) moist; moderate Landform: coarse subangular blocky structure; hard, friable, • Shambo—Alluvial fans slightly sticky, slightly plastic; few fine and • Noonan—Alluvial fans common very fine roots; common very fine pores Slope: and few fine pores; neutral; clear smooth • Shambo—4 to 15 percent boundary. • Noonan—4 to 15 percent Bw3—23 to 30 inches; light yellowish brown (2.5Y Mean annual precipitation: 15 to 17 inches 6/4) loam, olive brown (2.5Y 4/4) moist; moderate Composition coarse subangular blocky structure; hard, firm, slightly sticky, slightly plastic; few very fine and Major Components fine roots; few very fine and fine pores; slightly Shambo and similar soils: 45 percent alkaline; gradual wavy boundary. Noonan and similar soils: 40 percent Bk—30 to 60 inches; pale yellow (2.5Y 7/4) clay Minor Components loam, light olive brown (2.5Y 5/4) moist; weak Deep moderately saline soils: 0 to 4 percent coarse subangular blocky structure; hard, firm, Cabba and similar soils: 0 to 4 percent slightly sticky, slightly plastic; few very fine roots; Shallow cobbly soils: 0 to 4 percent few very fine pores; common fine masses and Shallow bouldery soils: 0 to 3 percent seams of lime; strongly effervescent; moderately alkaline. Major Component Description Shambo Range in Characteristics Surface layer texture: Loam Thickness of the mollic epipedon: 7 to 16 inches Depth class: Very deep (more than 60 inches) Depth to the Bk horizon: 14 to 30 inches Drainage class: Well drained Dominant parent material: Alluvium A horizon Native plant cover type: Rangeland Value: 3, 4, or 5 dry; 2 or 3 moist Flooding: None Chroma: 2 or 3 Available water capacity: Mainly 10.9 inches Clay content: 10 to 27 percent Reaction: pH 6.6 to 7.8 Noonan Bw horizons Surface layer texture: Loam Hue: 10YR or 2.5Y Depth class: Very deep (more than 60 inches) Value: 4, 5, or 6 dry; 3 or 4 moist Drainage class: Well drained Chroma: 2 to 4 Dominant parent material: Alluvium Texture: Loam, silt loam, or clay loam Native plant cover type: Rangeland Clay content: 18 to 35 percent Flooding: None Reaction: pH 6.6 to 8.4 Sodium affected: Sodic within 30 inches Available water capacity: Mainly 9.2 inches Bk horizon Hue: 10YR, 2.5Y, or 5Y A typical soil description with range in Value: 5, 6, or 7 dry; 4, 5, or 6 moist characteristics is included, in alphabetical order, Chroma: 2 to 4 in this section. Texture: Loam, clay loam, silty clay loam, or silt loam Management Clay content: 18 to 35 percent Calcium carbonate equivalent: 10 to 15 percent For management information about this map unit, Reaction: pH 7.4 to 9.0 see appropriate sections in Part II of this publication. 142 Soil Survey

231D—Shambo-Mowbray-Parchin Sodium affected: Sodic within 30 inches complex, 4 to 25 percent slopes Available water capacity: Mainly 4.1 inches A typical soil description with range in Setting characteristics is included, in alphabetical order, Landform: in this section. • Shambo—Sedimentary plains and hills Management • Mowbray—Hills • Parchin—Sedimentary plains For management information about this map unit, Slope: see appropriate sections in Part II of this publication. • Shambo—4 to 15 percent • Mowbray—15 to 25 percent • Parchin—4 to 8 percent Tanna Series Mean annual precipitation: 15 to 17 inches Depth class: Moderately deep (20 to 40 inches) Composition Drainage class: Well drained Major Components Permeability: Slow (0.06 to 0.2 inch/hour) Shambo and similar soils: 40 percent Landform: Sedimentary plains and hills Mowbray and similar soils: 25 percent Parent material: Semiconsolidated shale Parchin and similar soils: 20 percent Slope range: 2 to 15 percent Annual precipitation: 12 to 15 inches Minor Components Cabba and similar soils: 0 to 4 percent Taxonomic Class: Fine, montmorillonitic Aridic Reeder and similar soils: 0 to 4 percent Argiborolls Vebar and similar soils: 0 to 3 percent Very shallow sandy soils: 0 to 2 percent Typical Pedon Areas of slickspots: 0 to 2 percent Tanna silty clay loam, 2 to 8 percent slopes, in an Major Component Description area of rangeland, 500 feet north and 500 feet west of the southeast corner of sec. 20, T. 9 S., R. 61 E. Shambo Surface layer texture: Loam A1—0 to 2 inches; dark grayish brown (10YR 4/2) Depth class: Very deep (more than 60 inches) silty clay loam, very dark grayish brown (10YR Drainage class: Well drained 3/2) moist; moderate fine granular structure; soft, Dominant parent material: Alluvium friable, slightly sticky, plastic; many very fine and Native plant cover type: Rangeland fine roots; slightly alkaline; abrupt smooth Flooding: None boundary. Available water capacity: Mainly 10.9 inches A2—2 to 7 inches; dark grayish brown (10YR 4/2) silty clay loam, very dark grayish brown (10YR Mowbray 3/2) moist; moderate medium subangular blocky Surface layer texture: Very channery loam structure; hard, friable, moderately sticky, Depth class: Very deep (more than 60 inches) moderately plastic; many very fine and fine roots; Drainage class: Well drained many very fine pores; slightly alkaline; clear Dominant parent material: Colluvium smooth boundary. Native plant cover type: Forestland Bt—7 to 19 inches; grayish brown (10YR 5/2) silty Flooding: None clay loam, dark grayish brown (10YR 4/2) moist; Available water capacity: Mainly 4.4 inches moderate coarse prismatic structure parting to strong medium subangular blocky; very hard, Parchin firm, moderately sticky, moderately plastic; few Surface layer texture: Fine sandy loam fine and many very fine roots; common very fine Depth class: Moderately deep (20 to 40 inches) pores; many distinct clay films on faces of peds Drainage class: Well drained and in pores; slightly alkaline; gradual smooth Dominant parent material: Semiconsolidated, loamy boundary. sedimentary beds Bk—19 to 27 inches; pale brown (10YR 6/3) clay, Native plant cover type: Rangeland brown (10YR 4/3) moist; massive; hard, friable, Flooding: None moderately sticky, moderately plastic; few very Carter County, Montana—Part I 143

fine roots; few very fine pores; many medium and 64C—Tanna silty clay loam, common fine masses of lime; strongly 2 to 8 percent slopes effervescent; moderately alkaline; gradual smooth boundary. Setting Cr—27 to 60 inches; light brownish gray (10YR 6/2) semiconsolidated shale that crushes to clay Landform: Sedimentary plains loam, dark grayish brown (10YR 4/2) moist. Slope: 2 to 8 percent Mean annual precipitation: 12 to 15 inches Range in Characteristics Composition Soil temperature: 40 to 47 degrees F Thickness of the mollic epipedon: 7 to 12 inches Major Components Depth to the Bk horizon: 10 to 20 inches Tanna and similar soils: 85 percent Depth to bedrock: 20 to 40 inches Minor Components A horizons Cabbart and similar soils: 0 to 3 percent Hue: 10YR or 2.5Y Eapa and similar soils: 0 to 3 percent Value: 2 or 3 moist Weingart and similar soils: 0 to 3 percent Chroma: 2 or 3 Delpoint and similar soils: 0 to 3 percent Clay content: 27 to 35 percent Marvan and similar soils: 0 to 2 percent Content of rock fragments: 0 to 10 percent—0 to Soils that have slopes more than 8 percent: 0 to 5 percent cobbles; 0 to 5 percent channers 1 percent Reaction: pH 6.6 to 7.8 Major Component Description Bt horizon Surface layer texture: Silty clay loam Hue: 10YR or 2.5Y Depth class: Moderately deep (20 to 40 inches) Value: 3 or 4 moist Drainage class: Well drained Chroma: 2 or 3 Dominant parent material: Semiconsolidated, shale Texture: Clay loam, silty clay loam, clay, or silty residuum clay Native plant cover type: Rangeland Clay content: 35 to 50 percent Flooding: None Content of rock fragments: 0 to 10 percent—0 to Available water capacity: Mainly 4.4 inches 5 percent cobbles; 0 to 5 percent channers Electrical conductivity: 0 to 4 mmhos/cm A typical soil description with range in Reaction: pH 6.6 to 8.4 characteristics is included, in alphabetical order, Bk horizon in this section. Hue: 10YR or 2.5Y Management Value: 5 or 6 dry; 4 or 5 moist Chroma: 2 or 3 For management information about this map unit, Texture: Clay loam, silty clay loam, or clay see appropriate sections in Part II of this publication. Clay content: 35 to 50 percent Content of rock fragments: 0 to 10 percent—0 to 5 percent cobbles; 0 to 5 percent channers 164C—Tanna-Ethridge silty clay loams, Electrical conductivity: 2 to 4 mmhos/cm 2 to 8 percent slopes Calcium carbonate equivalent: 5 to 15 percent Reaction: pH 7.4 to 8.4 Setting Cr horizon Landform: Material: Semiconsolidated shale with thin layers • Tanna—Sedimentary plains of hard sandstone that are rippable • Ethridge—Alluvial fans 144 Soil Survey

Slope: Slope: • Tanna—2 to 8 percent • Tanna—8 to 15 percent • Ethridge—2 to 8 percent • Ethridge—8 to 15 percent Mean annual precipitation: 12 to 15 inches Mean annual precipitation: 12 to 15 inches Composition Composition Major Components Major Components Tanna and similar soils: 50 percent Tanna and similar soils: 55 percent Ethridge and similar soils: 35 percent Ethridge and similar soils: 30 percent Minor Components Minor Components Eapa and similar soils: 0 to 3 percent Weingart and similar soils: 0 to 4 percent Weingart and similar soils: 0 to 3 percent Cabbart and similar soils: 0 to 3 percent Cabbart and similar soils: 0 to 3 percent Delpoint and similar soils: 0 to 3 percent Delpoint and similar soils: 0 to 2 percent Soils with sandy loam surface layers: 0 to 3 percent Soils with sandy loam surface layers: 0 to 2 percent Soils that have slopes more than 15 percent: 0 to Soils that have slopes less than 2 percent: 0 to 2 percent 2 percent Major Component Description Major Component Description Tanna Tanna Surface layer texture: Silty clay loam Surface layer texture: Silty clay loam Depth class: Moderately deep (20 to 40 inches) Depth class: Moderately deep (20 to 40 inches) Drainage class: Well drained Drainage class: Well drained Dominant parent material: Semiconsolidated shale Dominant parent material: Semiconsolidated shale residuum residuum Native plant cover type: Rangeland Native plant cover type: Rangeland Flooding: None Flooding: None Available water capacity: Mainly 4.4 inches Available water capacity: Mainly 4.4 inches Ethridge Ethridge Surface layer texture: Silty clay loam Surface layer texture: Silty clay loam Depth class: Very deep (more than 60 inches) Depth class: Very deep (more than 60 inches) Drainage class: Well drained Drainage class: Well drained Dominant parent material: Alluvium Dominant parent material: Alluvium Native plant cover type: Rangeland Native plant cover type: Rangeland Flooding: None Flooding: None Available water capacity: Mainly 9.9 inches Available water capacity: Mainly 9.9 inches A typical soil description with range in A typical soil description with range in characteristics is included, in alphabetical order, characteristics is included, in alphabetical order, in this section. in this section. 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. Teigen Series 164D—Tanna-Ethridge silty clay loams, 8 to 15 percent slopes Depth class: Very deep (more than 60 inches) Drainage class: Well drained Permeability: Slow (0.06 to 0.2 inch/hour) Setting Landform: Alluvial fans and stream terraces Landform: Parent material: Alluvium • Tanna—Hills Slope range: 0 to 15 percent • Ethridge—Alluvial fans Annual precipitation: 12 to 15 inches Carter County, Montana—Part I 145

Taxonomic Class: Fine, montmorillonitic, frigid Aridic Bw horizons Ustochrepts Hue: 10YR, 2.5Y, or 5Y Value: 4, 5, or 6 dry; 3 or 4 moist Typical Pedon Chroma: 1 or 2 Teigen silty clay loam, 0 to 4 percent slopes, in an Texture: Clay loam, silty clay loam, or silty clay area of rangeland, 1,340 feet north and 240 feet east Clay content: 35 to 55 percent of the southwest corner of sec. 24, T. 9 S., R. 58 E. Content of rock fragments: 0 to 10 percent shale fragments—0 to 5 percent soft shale; 0 to A—0 to 3 inches; light brownish gray (10YR 6/2) silty 5 percent hard shale clay loam, very dark grayish brown (10YR 3/2) Reaction: pH 4.5 to 6.5 moist; moderate thick platy structure; slightly hard, firm, moderately sticky, moderately plastic; BC and C horizons few very fine and fine roots; few very fine pores; Hue: 10YR, 2.5Y, or 5Y moderately acid; clear smooth boundary. Value: 4, 5, or 6 dry; 3 or 4 moist Bw1—3 to 15 inches; light brownish gray (10YR 6/2) Chroma: 1 or 2 clay loam, very dark grayish brown (10YR 3/2) Texture: Loam, silt loam, clay loam, silty clay moist; strong medium subangular blocky loam, or silty clay structure; hard, firm, moderately sticky, Clay content: 35 to 55 percent moderately plastic; few very fine roots; common Content of rock fragments: 5 to 15 percent shale very fine pores; moderately acid; gradual smooth fragments—5 to 10 percent soft shale; 0 to boundary. 5 percent hard shale Bw2—15 to 24 inches; grayish brown (10YR 5/2) silty Reaction: pH 4.5 to 6.5 clay loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium subangular blocky structure; hard, firm, moderately sticky, 95A—Teigen silty clay loam, moderately plastic; few very fine roots; few very 0 to 4 percent slopes fine pores; 5 percent soft shale channers; moderately acid; gradual wavy boundary. BC—24 to 28 inches; grayish brown (10YR 5/2) clay Setting loam, very dark grayish brown (10YR 3/2) moist; Landform: Alluvial fans and stream terraces massive; slightly hard, friable, moderately sticky, Slope: 0 to 4 percent moderately plastic; few very fine roots; few very Mean annual precipitation: 12 to 15 inches fine pores; 5 percent pebbles and 10 percent soft shale channers; slightly acid; gradual wavy Composition boundary. C—28 to 60 inches; grayish brown (10YR 5/2) silty Major Components clay loam, very dark grayish brown (10YR 3/2) Teigen and similar soils: 85 percent moist; massive; slightly hard, friable, moderately sticky, moderately plastic; 5 percent soft shale Minor Components channers; moderately acid. Vaeda and similar soils: 0 to 4 percent Creed and similar soils: 0 to 3 percent Range in Characteristics Marvan and similar soils: 0 to 3 percent Soil temperature: 41 to 47 degrees F Yamacall and similar soils: 0 to 3 percent Soil phases: Gullied Soils that have slopes more than 4 percent: 0 to 2 percent A horizon Hue: 10YR, 2.5Y, or 5Y Major Component Description Value: 5 or 6 dry; 3 or 4 moist Chroma: 1 or 2 Surface layer texture: Silty clay loam Texture: Silty clay loam or clay loam Depth class: Very deep (more than 60 inches) Clay content: 30 to 40 percent Drainage class: Well drained Content of rock fragments: 0 to 10 percent shale Dominant parent material: Alluvium fragments—0 to 5 percent soft shale; 0 to Native plant cover type: Rangeland 5 percent hard shale Flooding: None Reaction: pH 4.5 to 6.0 Available water capacity: Mainly 9.9 inches 146 Soil Survey

A typical soil description with range in Parent material: Alluvium characteristics is included, in alphabetical order, Slope range: 4 to 45 percent in this section. Annual precipitation: 12 to 15 inches Management Taxonomic Class: Loamy-skeletal, mixed Aridic Calciborolls For management information about this map unit, see appropriate sections in Part II of this publication. Typical Pedon Tricart clay loam, 4 to 15 percent slopes, in an area of 95D—Teigen clay loam, gullied, rangeland, 2,500 feet north and 500 feet east of the 4 to 15 percent slopes southwest corner of sec. 11, T. 5 S., R. 59 E. A1—0 to 1 inch; grayish brown (10YR 5/2) loam, very Setting dark grayish brown (10YR 3/2) moist; moderate fine and medium granular structure; soft, very Landform: Alluvial fans friable, slightly sticky, slightly plastic; common fine Slope: 4 to 15 percent and many very fine roots; common very fine Mean annual precipitation: 12 to 15 inches pores; neutral; clear smooth boundary. Composition A2—1 to 6 inches; brown (10YR 5/3) clay loam, dark brown (10YR 3/3) moist; moderate medium Major Components prismatic structure parting to weak fine and Teigen and similar soils: 85 percent medium subangular blocky; slightly hard, friable, Minor Components slightly sticky, slightly plastic; few fine and Vaeda and similar soils: 0 to 4 percent common very fine roots; few very fine pores; Neldore and similar soils: 0 to 4 percent 5 percent pebbles; slightly alkaline; clear wavy Soils that are calcareous throughout: 0 to 4 percent boundary. Weingart and similar soils: 0 to 3 percent Bk1—6 to 13 inches; light brownish gray (2.5Y 6/2) clay loam, dark grayish brown (2.5Y 4/2) moist; Major Component Description weak medium prismatic structure parting to weak Surface layer texture: Clay loam fine and medium subangular blocky; slightly hard, Depth class: Very deep (more than 60 inches) friable, slightly sticky, moderately plastic; common Drainage class: Well drained very fine roots; few very fine pores; 10 percent Dominant parent material: Alluvium pebbles; common fine and medium masses of Native plant cover type: Rangeland lime; strongly effervescent; slightly alkaline; Flooding: None gradual wavy boundary. Available water capacity: Mainly 9.9 inches 2Bk2—13 to 25 inches; light gray (10YR 7/2) very gravelly loam, grayish brown (10YR 5/2) moist; A typical soil description with range in weak medium subangular blocky structure; soft, characteristics is included, in alphabetical order, very friable, nonsticky, nonplastic; common very in this section. fine roots; few very fine pores; 40 percent pebbles; common distinct lime coats on surfaces Management of pebbles; many fine and medium masses of For management information about this map unit, lime; violently effervescent; moderately alkaline, see appropriate sections in Part II of this publication. gradual wavy boundary. 2Bk3—25 to 60 inches; light gray (10YR 7/2) very gravelly loam, grayish brown (10YR 5/2) moist; Tricart Series weak fine subangular blocky structure; soft, very friable, nonsticky, nonplastic; common very fine Depth class: Very deep (more than 60 inches) roots; 55 percent pebbles; common distinct lime Drainage class: Well drained coats on surfaces of pebbles; many fine and Permeability: Moderate (0.6 to 2.0 inches/hour) medium masses of lime; violently effervescent; Landform: Relict stream terraces moderately alkaline. Carter County, Montana—Part I 147

Range in Characteristics Composition Soil temperature: 42 to 47 degrees F Major Components Thickness of the mollic epipedon: 7 to 10 inches Tricart and similar soils: 85 percent A1 horizon Minor Components Hue: 10YR or 2.5Y Yamacall and similar soils: 0 to 4 percent Chroma: 2 or 3 Soils with gravelly surfaces: 0 to 4 percent Texture: Loam or clay loam when mixed to Delpoint and similar soils: 0 to 3 percent 7 inches Soils with lighter colored surface layers: 0 to Clay content: 15 to 35 percent 2 percent Content of rock fragments: 0 to 35 percent Soils that have slopes more than 15 percent: 0 to pebbles 2 percent Reaction: pH 6.6 to 8.4 Major Component Description A2 horizon Hue: 10YR or 2.5Y Surface layer texture: Clay loam Chroma: 2 or 3 Depth class: Very deep (more than 60 inches) Texture: Loam or clay loam Drainage class: Well drained Clay content: 15 to 35 percent Dominant parent material: Alluvium Content of rock fragments: 0 to 35 percent Native plant cover type: Rangeland pebbles Flooding: None Reaction: pH 6.6 to 8.4 Available water capacity: Mainly 6.1 inches Bk1 horizon Hue: 10YR or 2.5Y A typical soil description with range in Value: 6 or 7 dry; 4, 5, or 6 moist characteristics is included, in alphabetical order, Chroma: 2 or 3 in this section. Texture: Sandy loam, loam, or clay loam Management Clay content: 15 to 35 percent Content of rock fragments: 10 to 35 percent For management information about this map unit, pebbles see appropriate sections in Part II of this publication. Calcium carbonate equivalent: 10 to 30 percent Reaction: pH 7.4 to 8.4 2Bk horizons 23E—Tricart gravelly loam, Hue: 10YR or 2.5Y 15 to 45 percent slopes Value: 6 or 7 dry; 5 or 6 moist Chroma: 2 or 3 Setting Texture: Loam or sandy loam Clay content: 5 to 15 percent Landform: Relict stream terraces Content of rock fragments: 35 to 60 percent Slope: 15 to 45 percent pebbles Mean annual precipitation: 12 to 15 inches Calcium carbonate equivalent: 15 to 30 percent Composition Reaction: pH 7.4 to 8.4 Major Components Tricart and similar soils: 85 percent 23D—Tricart clay loam, 4 to 15 percent slopes Minor Components Delpoint and similar soils: 0 to 4 percent Soils with very gravelly surfaces: 0 to 4 percent Setting Soils with darker colored surface layers: 0 to Landform: Relict stream terraces 4 percent Slope: 4 to 15 percent Soils that have slopes less than 15 percent: 0 to Mean annual precipitation: 12 to 15 inches 3 percent 148 Soil Survey

Major Component Description Bw2—12 to 18 inches; grayish brown (2.5Y 5/2) fine sandy loam, dark grayish brown (2.5Y 4/2) moist; Surface layer texture: Gravelly loam weak coarse prismatic structure parting to weak Depth class: Very deep (more than 60 inches) medium subangular blocky; slightly hard, very Drainage class: Well drained friable, nonsticky, nonplastic; common very fine Dominant parent material: Alluvium roots; few very fine pores; slightly alkaline; clear Native plant cover type: Rangeland wavy boundary. Flooding: None Bk—18 to 30 inches; light brownish gray (2.5Y 6/2) Available water capacity: Mainly 5.3 inches fine sandy loam, grayish brown (2.5Y 5/2) moist; weak coarse prismatic structure; soft, very friable, A typical soil description with range in nonsticky, nonplastic; few very fine roots; few very characteristics is included, in alphabetical order, fine pores; few fine and medium masses of lime; in this section. strongly effervescent; moderately alkaline; Management gradual wavy boundary. Cr—30 to 60 inches; light brownish gray (2.5Y 6/2) For management information about this map unit, semiconsolidated, sandy sedimentary beds that see appropriate sections in Part II of this publication. crush to fine sandy loam, grayish brown (2.5Y 5/2) moist. Twilight Series Range in Characteristics Depth to the Bk horizon: 10 to 20 inches Depth class: Moderately deep (20 to 40 inches) Depth to the Cr horizon: 20 to 40 inches Drainage class: Well drained Permeability: Moderately rapid (2.0 to 6.0 inches/ A horizon hour) Hue: 10YR or 2.5Y Landform: Sedimentary plains and hills Value: 4 or 5 dry; 3 or 4 moist Parent material: Semiconsolidated, sandy Chroma: 2 or 3 sedimentary beds Clay content: 5 to 18 percent Slope range: 2 to 45 percent Reaction: pH 6.6 to 7.8 Annual precipitation: 12 to 15 inches Bw horizons Hue: 10YR or 2.5Y Taxonomic Class: Coarse-loamy, mixed, frigid Aridic Value: 5 or 6 dry; 4 or 5 moist Ustochrepts Chroma: 2 to 4 Texture: Fine sandy loam or sandy loam Typical Pedon Clay content: 5 to 18 percent Reaction: pH 6.6 to 7.8 Twilight fine sandy loam, in an area of Blacksheep- Twilight fine sandy loams, 8 to 15 percent slopes, in Bk horizon an area of rangeland, 1,000 feet north and 2,700 feet Hue: 10YR or 2.5Y east of the southwest corner of sec. 18, T. 2 S., Value: 5, 6, or 7 dry; 4, 5, or 6 moist R. 56 E. Chroma: 1 to 4 Texture: Fine sandy loam or sandy loam A—0 to 3 inches; dark grayish brown (2.5Y 4/2) fine Clay content: 5 to 18 percent sandy loam, very dark grayish brown (2.5Y 3/2) Calcium carbonate equivalent: 5 to 10 percent moist; weak fine granular structure; slightly hard, Reaction: pH 7.4 to 8.4 very friable, nonsticky, nonplastic; few medium and common very fine roots; neutral; clear smooth boundary. 69C—Twilight fine sandy loam, Bw1—3 to 12 inches; light olive brown (2.5Y 5/4) fine 2 to 8 percent slopes sandy loam, dark grayish brown (2.5Y 4/2) moist; weak coarse prismatic structure parting to weak Setting fine and medium subangular blocky; slightly hard, very friable, nonsticky, nonplastic; few fine and Landform: Sedimentary plains common very fine roots; few very fine and fine Slope: 2 to 8 percent pores; slightly alkaline; clear wavy boundary. Mean annual precipitation: 12 to 15 inches Carter County, Montana—Part I 149

Composition Dominant parent material: Semiconsolidated, sandy sedimentary beds Major Components Native plant cover type: Rangeland Twilight and similar soils: 85 percent Flooding: None Minor Components Available water capacity: Mainly 4.2 inches Bonfri and similar soils: 0 to 3 percent Busby and similar soils: 0 to 3 percent A typical soil description with range in Cabbart and similar soils: 0 to 3 percent characteristics is included, in alphabetical order, Yamacall and similar soils: 0 to 2 percent in this section. Delpoint and similar soils: 0 to 2 percent Management Chinook and similar soils: 0 to 2 percent For management information about this map unit, Major Component Description see appropriate sections in Part II of this publication. Surface layer texture: Fine sandy loam Depth class: Moderately deep (20 to 40 inches) Drainage class: Well drained 269C—Twilight-Bonfri complex, Dominant parent material: Semiconsolidated, sandy 2 to 8 percent slopes sedimentary beds Native plant cover type: Rangeland Flooding: None Setting Available water capacity: Mainly 4.2 inches Landform: • Twilight—Sedimentary plains A typical soil description with range in • Bonfri—Sedimentary plains characteristics is included, in alphabetical order, Position on landform: in this section. • Twilight—Shoulders and summits Management • Bonfri—Backslopes and shoulders Slope: For management information about this map unit, • Twilight—2 to 8 percent see appropriate sections in Part II of this publication. • Bonfri—2 to 8 percent Mean annual precipitation: 12 to 15 inches 69D—Twilight fine sandy loam, Composition 8 to 15 percent slopes Major Components Twilight and similar soils: 55 percent Setting Bonfri and similar soils: 30 percent Landform: Hills Minor Components Slope: 8 to 15 percent Blacksheep and similar soils: 0 to 3 percent Mean annual precipitation: 12 to 15 inches Cambeth and similar soils: 0 to 3 percent Composition Busby and similar soils: 0 to 3 percent Weingart and similar soils: 0 to 2 percent Major Components Cabbart and similar soils: 0 to 2 percent Twilight and similar soils: 85 percent Chinook and similar soils: 0 to 2 percent Minor Components Major Component Description Blacksheep and similar soils: 0 to 3 percent Busby and similar soils: 0 to 3 percent Twilight Chinook and similar soils: 0 to 3 percent Surface layer texture: Fine sandy loam Cabbart and similar soils: 0 to 3 percent Depth class: Moderately deep (20 to 40 inches) Delpoint and similar soils: 0 to 3 percent Drainage class: Well drained Dominant parent material: Semiconsolidated, sandy Major Component Description sedimentary beds Surface layer texture: Fine sandy loam Native plant cover type: Rangeland Depth class: Moderately deep (20 to 40 inches) Flooding: None Drainage class: Well drained Available water capacity: Mainly 4.2 inches 150 Soil Survey

Bonfri Dominant parent material: Semiconsolidated, sandy Surface layer texture: Loam sedimentary beds Depth class: Moderately deep (20 to 40 inches) Native plant cover type: Rangeland Drainage class: Well drained Flooding: None Dominant parent material: Interbedded sandstone Available water capacity: Mainly 4.2 inches and shale residuum Native plant cover type: Rangeland Bonfri Flooding: None Surface layer texture: Loam Available water capacity: Mainly 5.1 inches Depth class: Moderately deep (20 to 40 inches) Drainage class: Well drained A typical soil description with range in Dominant parent material: Interbedded sandstone characteristics is included, in alphabetical order, and shale residuum in this section. Native plant cover type: Rangeland Flooding: None Management Available water capacity: Mainly 5.1 inches For management information about this map unit, see appropriate sections in Part II of this publication. A typical soil description with range in characteristics is included, in alphabetical order, in this section. 269D—Twilight-Bonfri complex, 8 to 15 percent slopes Management For management information about this map unit, Setting see appropriate sections in Part II of this publication. Landform: • Twilight—Hills 369C—Twilight-Delpoint complex, • Bonfri—Hills 2 to 8 percent slopes Position on landform: • Twilight—Shoulders and summits Setting • Bonfri—Backslopes and shoulders Slope: Landform: • Twilight—8 to 15 percent • Twilight—Sedimentary plains • Bonfri—8 to 15 percent • Delpoint—Sedimentary plains Mean annual precipitation: 12 to 15 inches Position on landform: • Twilight—Shoulders and summits Composition • Delpoint—Backslopes and shoulders Major Components Slope: Twilight and similar soils: 55 percent • Twilight—2 to 8 percent Bonfri and similar soils: 30 percent • Delpoint—2 to 8 percent Mean annual precipitation: 12 to 15 inches Minor Components Blacksheep and similar soils: 0 to 3 percent Composition Cabbart and similar soils: 0 to 3 percent Major Components Cambeth and similar soils: 0 to 3 percent Twilight and similar soils: 50 percent Yamacall and similar soils: 0 to 2 percent Delpoint and similar soils: 35 percent Weingart and similar soils: 0 to 2 percent Chinook and similar soils: 0 to 2 percent Minor Components Blacksheep and similar soils: 0 to 4 percent Major Component Description Bonfri and similar soils: 0 to 3 percent Twilight Cambeth and similar soils: 0 to 3 percent Surface layer texture: Fine sandy loam Yamacall and similar soils: 0 to 3 percent Depth class: Moderately deep (20 to 40 inches) Soils with darker colored surface layers: 0 to Drainage class: Well drained 2 percent Carter County, Montana—Part I 151

Major Component Description Weingart and similar soils: 0 to 2 percent Cambeth and similar soils: 0 to 2 percent Twilight Soils with darker colored surface layers: 0 to Surface layer texture: Fine sandy loam 2 percent Depth class: Moderately deep (20 to 40 inches) Drainage class: Well drained Major Component Description Dominant parent material: Semiconsolidated, sandy Twilight sedimentary beds Surface layer texture: Fine sandy loam Native plant cover type: Rangeland Depth class: Moderately deep (20 to 40 inches) Flooding: None Drainage class: Well drained Available water capacity: Mainly 4.2 inches Dominant parent material: Semiconsolidated, sandy sedimentary beds Delpoint Native plant cover type: Rangeland Surface layer texture: Loam Flooding: None Depth class: Moderately deep (20 to 40 inches) Available water capacity: Mainly 4.2 inches Drainage class: Well drained Dominant parent material: Semiconsolidated, loamy Cabbart sedimentary beds Surface layer texture: Loam Native plant cover type: Rangeland Depth class: Shallow (10 to 20 inches) Flooding: None Drainage class: Well drained Available water capacity: Mainly 4.5 inches Dominant parent material: Semiconsolidated, loamy sedimentary beds A typical soil description with range in Native plant cover type: Rangeland characteristics is included, in alphabetical order, Flooding: None in this section. Available water capacity: Mainly 2.9 inches Management A typical soil description with range in For management information about this map unit, characteristics is included, in alphabetical order, see appropriate sections in Part II of this publication. in this section. Management 369D—Twilight-Cabbart complex, 8 to 15 percent slopes For management information about this map unit, see appropriate sections in Part II of this publication. Setting Landform: Ustochrepts • Twilight—Hills • Cabbart—Hills Depth class: Moderately deep (20 to 40 inches) Position on landform: Drainage class: Well drained • Twilight—Backslopes and footslopes Permeability: Moderately slow (0.2 to 0.6 inch/hour) • Cabbart—Shoulders and summits to moderately rapid (2.0 to 6.0 inches/hour) Slope: Landform: Hills (slump area) • Twilight—8 to 15 percent Parent material: Semiconsolidated, loamy • Cabbart—8 to 15 percent sedimentary beds Mean annual precipitation: 12 to 15 inches Slope range: 15 to 45 percent Annual precipitation: 12 to 15 inches Composition Major Components Taxonomic Class: Aridic Ustochrepts Twilight and similar soils: 50 percent Cabbart and similar soils: 35 percent Typical Pedon Minor Components Ustochrepts, in an area of Ustochrepts-Haploborolls Blacksheep and similar soils: 0 to 3 percent complex, slump, 15 to 45 percent slopes, in an area Busby and similar soils: 0 to 3 percent of rangeland, 2,500 feet north and 500 feet west of Delpoint and similar soils: 0 to 3 percent the southeast corner of sec. 7, T. 4 S., R. 60 E. 152 Soil Survey

A—0 to 5 inches; pale brown (10YR 6/3) loam, brown Bw horizon (10YR 4/3) moist; weak fine subangular blocky Clay content: 12 to 27 percent structure; soft, very friable, slightly sticky, slightly Content of rock fragments: 10 to 35 percent— plastic; few medium and common very fine and 10 to 35 percent channers; 0 to 5 percent fine roots; disseminated lime; slightly flagstones effervescent; slightly alkaline; abrupt smooth Electrical conductivity: 2 to 16 mmhos/cm boundary. Sodium adsorption ratio: 0 to 30 Bw—5 to 12 inches; light brownish gray (10YR 6/2) Reaction: pH 7.4 to 9.0 channery loam, dark grayish brown (10YR 4/2) Bk horizons moist; strong medium subangular blocky Clay content: 12 to 35 percent structure; slightly hard, friable, slightly sticky, Content of rock fragments: 35 to 60 percent— slightly plastic; few medium and many very fine 35 to 60 percent channers; 0 to 10 percent and fine roots; few fine and many very fine pores; flagstones 15 percent channers and 5 percent flagstones; Electrical conductivity: 2 to 16 mmhos/cm disseminated lime; strongly effervescent; Sodium adsorption ratio: 0 to 30 moderately alkaline; clear smooth boundary. Calcium carbonate equivalent: 5 to 15 percent Bk1—12 to 20 inches; light yellowish brown (2.5Y Reaction: pH 7.4 to 9.0 6/4) very channery loam, olive brown (2.5Y 4/4) moist; moderate coarse subangular blocky structure; slightly hard, friable, slightly sticky, 17E—Ustochrepts-Haploborolls complex, slightly plastic; few medium and many very fine slump, 15 to 45 percent slopes roots; common fine and many very fine pores; 30 percent channers and 5 percent flagstones; Setting few fine masses and seams of lime; violently effervescent; strongly alkaline; clear smooth Landform: boundary. • Ustochrepts—Hills Bk2—20 to 37 inches; light yellowish brown (2.5Y • Haploborolls—Hills 6/4) very channery loam, olive brown (2.5Y 4/4) Slope: moist; massive; slightly hard, friable, slightly • Ustochrepts—15 to 45 percent sticky, slightly plastic; few medium and common • Haploborolls—15 to 45 percent very fine and fine roots; 35 percent channers and Mean annual precipitation: 12 to 15 inches 5 percent flagstones; few fine masses of lime; Composition violently effervescent; strongly alkaline; clear wavy boundary. Major Components Cr—37 to 60 inches; semiconsolidated, loamy Ustochrepts and similar soils: 45 percent sedimentary beds. Haploborolls and similar soils: 40 percent Range in Characteristics Minor Components Yawdim and similar soils: 0 to 4 percent Content of soft coarse fragments in the control Areas of rock outcrop: 0 to 3 percent section: 0 to 80 percent Areas of gullied land: 0 to 3 percent Content of rock fragments in the control section: 35 to Areas with ponderosa pines: 0 to 3 percent 60 percent channers or flagstones Soils that have slopes less than 15 percent: 0 to Depth to calcium carbonate: 0 to 10 inches 1 percent Other features: Soft coarse fragments increase with Very poorly drained soils: 0 to 1 percent depth. Major Component Description A horizon Clay content: 12 to 27 percent Ustochrepts Content of rock fragments: 0 to 10 percent Surface layer texture: Loam flagstones and channers Depth class: Moderately deep (20 to 40 inches) Electrical conductivity: 2 to 16 mmhos/cm Drainage class: Well drained Sodium adsorption ratio: 0 to 30 Dominant parent material: Semiconsolidated, loamy Reaction: pH 7.4 to 9.0 sedimentary beds Carter County, Montana—Part I 153

Native plant cover type: Rangeland By1—8 to 24 inches; light brownish gray (10YR 6/2) Flooding: None silty clay loam, grayish brown (10YR 5/2) moist; Salt affected: Saline within 30 inches moderate fine and medium subangular blocky Sodium affected: Sodic within 30 inches structure; hard, friable, very sticky, moderately Available water capacity: Mainly 4.1 inches plastic; few very fine and fine roots; common very fine pores; common fine nests and seams of Haploborolls gypsum crystals; slightly alkaline; gradual wavy Surface layer texture: Channery fine sandy loam boundary. Depth class: Very deep (more than 60 inches) By2—24 to 60 inches; light brownish gray (10YR 6/2) Drainage class: Well drained silty clay loam, dark gray (10YR 4/1) moist; Dominant parent material: Alluvium or colluvium moderate fine and medium subangular blocky Native plant cover type: Rangeland structure; hard, firm, very sticky, moderately Flooding: None plastic; few very fine and fine roots; common very Available water capacity: Mainly 8.9 inches fine pores; few fine seams and nests of gypsum crystals; slightly alkaline. A typical soil description with range in Range in Characteristics characteristics is included, in alphabetical order, in this section. Soil temperature: 42 to 47 degrees F Depth to the By horizon: 6 to 15 inches Management E and Bw horizons For management information about this map unit, Hue: 10YR, 2.5Y, or 5Y see appropriate sections in Part II of this publication. Value: 5, 6, or 7 dry; 4, 5, or 6 moist Chroma: 2 or 3 Clay content: 35 to 40 percent Vaeda Series Content of rock fragments: 0 to 15 percent pebbles Depth class: Very deep (more than 60 inches) Electrical conductivity: 2 to 4 mmhos/cm Drainage class: Well drained Sodium adsorption ratio: 0 to 5 Permeability: Very slow (<0.06 inch/hour) Reaction: pH 5.6 to 7.8 Landform: Alluvial fans and stream terraces Parent material: Alluvium By1 horizon Slope range: 0 to 4 percent Hue: 10YR, 2.5Y, or 5Y Annual precipitation: 12 to 15 inches Value: 5 or 6 dry; 4 or 5 moist Chroma: 2 or 3 Taxonomic Class: Fine, montmorillonitic, nonacid, Texture: Silty clay loam, silty clay, or clay frigid Aridic Ustochrepts Clay content: 35 to 60 percent Content of rock fragments: 0 to 15 percent Typical Pedon pebbles Vaeda silty clay loam, 0 to 2 percent slopes, in an Electrical conductivity: 4 to 16 mmhos/cm area of rangeland, 2,400 feet south and 1,900 feet Sodium adsorption ratio: 10 to 20 east of the northwest corner of sec. 8, T. 9 S., R. 61 E. Gypsum content: 1 to 5 percent Reaction: pH 6.1 to 7.8 E—0 to 2 inches; light gray (10YR 7/2) silty clay loam, dark grayish brown (10YR 4/2) moist; moderate By2 horizon thin platy structure; soft, very friable, very sticky, Hue: 10YR, 2.5Y, or 5Y moderately plastic; few very fine and fine roots; Value: 5 or 6 dry; 4 or 5 moist common very fine and fine pores; neutral; gradual Chroma: 1 to 3 wavy boundary. Texture: Silty clay loam, silty clay, or clay Bw—2 to 8 inches; light brownish gray (10YR 6/2) Clay content: 35 to 60 percent silty clay loam, dark grayish brown (10YR 4/2) Content of rock fragments: 0 to 15 percent moist; moderate fine and medium subangular pebbles blocky structure; hard, friable, very sticky, Electrical conductivity: 4 to 16 mmhos/cm moderately plastic; few very fine and fine roots; Sodium adsorption ratio: 10 to 20 common very fine pores; neutral; clear smooth Gypsum content: 1 to 5 percent boundary. Reaction: pH 6.1 to 8.4 154 Soil Survey

96A—Vaeda silty clay loam, Composition 0 to 2 percent slopes Major Components Vaeda and similar soils: 70 percent Setting Creed and similar soils: 20 percent Landform: Alluvial fans and stream terraces Minor Components Slope: 0 to 2 percent Bickerdyke and similar soils: 0 to 3 percent Mean annual precipitation: 12 to 15 inches Vanda and similar soils: 0 to 3 percent Gerdrum and similar soils: 0 to 2 percent Composition Soils that have slopes more than 4 percent: 0 to Major Components 2 percent Vaeda and similar soils: 85 percent Major Component Description Minor Components Vaeda Vanda and similar soils: 0 to 4 percent Surface layer texture: Silty clay loam Bickerdyke and similar soils: 0 to 3 percent Depth class: Very deep (more than 60 inches) Absher and similar soils: 0 to 3 percent Drainage class: Well drained Gerdrum and similar soils: 0 to 3 percent Dominant parent material: Alluvium Soils that have slopes more than 2 percent: 0 to Native plant cover type: Rangeland 2 percent Flooding: None Major Component Description Salt affected: Saline within 30 inches Sodium affected: Sodic within 30 inches Surface layer texture: Silty clay loam Available water capacity: Mainly 6.7 inches Depth class: Very deep (more than 60 inches) Drainage class: Well drained Creed Dominant parent material: Alluvium Surface layer texture: Loam Native plant cover type: Rangeland Depth class: Very deep (more than 60 inches) Flooding: None Drainage class: Well drained Salt affected: Saline within 30 inches Dominant parent material: Alluvium Sodium affected: Sodic within 30 inches Native plant cover type: Rangeland Available water capacity: Mainly 6.7 inches Flooding: None Salt affected: Saline within 30 inches A typical soil description with range in Sodium affected: Sodic within 30 inches characteristics is included, in alphabetical order, Available water capacity: Mainly 6.7 inches in this section. Management A typical soil description with range in characteristics is included, in alphabetical order, For management information about this map unit, in this section. see appropriate sections in Part II of this publication. Management For management information about this map unit, 196C—Vaeda-Creed complex, see appropriate sections in Part II of this publication. 0 to 4 percent slopes

Setting Vanda Series Landform: Depth class: Very deep (more than 60 inches) • Vaeda—Alluvial fans Drainage class: Well drained • Creed—Alluvial fans Permeability: Very slow (<0.06 inch/hour) Slope: Landform: Alluvial fans and stream terraces • Vaeda—0 to 4 percent Parent material: Alluvium • Creed—0 to 4 percent Slope range: 0 to 8 percent Mean annual precipitation: 12 to 15 inches Annual precipitation: 12 to 15 inches Carter County, Montana—Part I 155

Taxonomic Class: Fine, montmorillonitic Clay content: 35 to 60 percent (calcareous), frigid Aridic Ustorthents Gypsum content: 1 to 5 percent with total gypsum less than 150 Typical Pedon Electrical conductivity: 8 to 16 mmhos/cm Vanda silty clay loam, 0 to 2 percent slopes, in an Sodium adsorption ratio: 13 to 30 area of rangeland, 1,200 feet south and 600 feet east Gypsum content: 1 to 5 percent of the northwest corner of sec. 2, T. 8 S., R. 60 E. Reaction: pH 7.8 to 9.6 A—0 to 3 inches; light gray (2.5Y 7/2) silty clay loam, grayish brown (2.5Y 5/2) moist; moderate fine 97A—Vanda silty clay loam, granular structure; slightly hard, friable, 0 to 2 percent slopes moderately sticky, moderately plastic; common very fine and fine roots; disseminated lime; Setting strongly effervescent; moderately alkaline; clear smooth boundary. Landform: Alluvial fans and stream terraces Byz1—3 to 17 inches; light brownish gray (2.5Y 6/2) Slope: 0 to 2 percent silty clay loam, dark grayish brown (2.5Y 4/2) Mean annual precipitation: 12 to 15 inches moist; massive; hard, firm, moderately sticky, Composition moderately plastic; common very fine and fine roots; common very fine pores; common seams Major Components and nests of gypsum crystals; few fine seams Vanda and similar soils: 85 percent and nests of other salts; disseminated lime; Minor Components strongly effervescent; strongly alkaline; clear Vaeda and similar soils: 0 to 4 percent smooth boundary. Marvan and similar soils: 0 to 4 percent Byz2—17 to 60 inches; light brownish gray (2.5Y 6/2) Absher and similar soils: 0 to 4 percent silty clay loam, grayish brown (2.5Y 4/2) moist; Kobase and similar soils: 0 to 3 percent massive; very hard, firm, moderately sticky, moderately plastic; few very fine roots; few very Major Component Description fine pores; few fine seams and nests of gypsum Surface layer texture: Silty clay loam crystals; few fine seams of other salts; Depth class: Very deep (more than 60 inches) disseminated lime; strongly effervescent; Drainage class: Well drained moderately alkaline. Dominant parent material: Alluvium Range in Characteristics Native plant cover type: Rangeland Flooding: None Soil temperature: 42 to 47 degrees F Salt affected: Saline within 30 inches Soil phases: Warm Sodium affected: Sodic within 30 inches Taxonomic note: Map unit 613B is a taxadjunct to Available water capacity: Mainly 6.1 inches the Vanda series in order to join soils that have an average soil temperature greater than A typical soil description with range in 47 degrees F. characteristics is included, in alphabetical order, A horizon in this section. Hue: 10YR, 2.5Y, or 5Y Management Value: 5, 6, or 7 dry; 4 or 5 moist Chroma: 1 to 3 For management information about this map unit, Texture: Clay or silty clay loam see appropriate sections in Part II of this publication. Clay content: 30 to 60 percent Electrical conductivity: 2 to 8 mmhos/cm Sodium adsorption ratio: 20 to 30 197A—Vanda-Marvan complex, Reaction: pH 7.8 to 9.6 0 to 2 percent slopes Byz horizons Setting Hue: 10YR, 2.5Y, or 5Y Value: 5 or 6 dry; 4 or 5 moist Landform: Chroma: 2 or 3 • Vanda—Alluvial fans and stream terraces Texture: Clay, silty clay, or silty clay loam • Marvan—Alluvial fans and stream terraces 156 Soil Survey

Slope: Slope: • Vanda—0 to 2 percent • Vanda—2 to 8 percent • Marvan—0 to 2 percent • Marvan—2 to 8 percent Mean annual precipitation: 12 to 15 inches Mean annual precipitation: 12 to 15 inches Composition Composition Major Components Major Components Vanda and similar soils: 45 percent Vanda and similar soils: 45 percent Marvan and similar soils: 40 percent Marvan and similar soils: 40 percent Minor Components Minor Components Absher and similar soils: 0 to 4 percent Absher and similar soils: 0 to 4 percent Vaeda and similar soils: 0 to 4 percent Vaeda and similar soils: 0 to 4 percent Gerdrum and similar soils: 0 to 4 percent Gerdrum and similar soils: 0 to 4 percent Kobase and similar soils: 0 to 3 percent Kobase and similar soils: 0 to 3 percent Major Component Description Major Component Description Vanda Vanda Surface layer texture: Silty clay loam Surface layer texture: Silty clay loam Depth class: Very deep (more than 60 inches) Depth class: Very deep (more than 60 inches) Drainage class: Well drained Drainage class: Well drained Dominant parent material: Alluvium Dominant parent material: Alluvium Native plant cover type: Rangeland Native plant cover type: Rangeland Flooding: None Flooding: None Salt affected: Saline within 30 inches Salt affected: Saline within 30 inches Sodium affected: Sodic within 30 inches Sodium affected: Sodic within 30 inches Available water capacity: Mainly 6.1 inches Available water capacity: Mainly 6.1 inches

Marvan Marvan Surface layer texture: Silty clay Surface layer texture: Silty clay Depth class: Very deep (more than 60 inches) Depth class: Very deep (more than 60 inches) Drainage class: Well drained Drainage class: Well drained Dominant parent material: Alluvium Dominant parent material: Alluvium Native plant cover type: Rangeland Native plant cover type: Rangeland Flooding: None Flooding: None Available water capacity: Mainly 6.9 inches Available water capacity: Mainly 6.9 inches

A typical soil description with range in A typical soil description with range in characteristics is included, in alphabetical order, characteristics is included, in alphabetical order, in this section. in this section. 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.

197C—Vanda-Marvan complex, Varney Series 2 to 8 percent slopes Depth class: Very deep (more than 60 inches) Drainage class: Well drained Permeability: Moderate (0.6 to 2.0 inches/hour) Setting Landform: Alluvial fans and stream terraces Landform: Parent material: Alluvium • Vanda—Alluvial fans and stream terraces Slope range: 0 to 8 percent • Marvan—Alluvial fans and stream terraces Annual precipitation: 12 to 15 inches Carter County, Montana—Part I 157

Taxonomic Class: Fine-loamy, mixed Aridic coats on rock fragments; common fine masses of Argiborolls lime; strongly effervescent; moderately alkaline. Typical Pedon Range in Characteristics Varney loam, 2 to 8 percent slopes, in an area of Soil temperature: 40 to 47 degrees F rangeland, 1,200 feet south and 400 feet west of the Thickness of the mollic epipedon: 7 to 16 inches northeast corner of sec. 4, T. 2 S., R. 57 E. Depth to the Bk horizon: 9 to 20 inches A—0 to 4 inches; brown (10YR 5/3) loam, dark brown A horizon (10YR 3/3) moist; moderate fine and medium Hue: 10YR or 2.5Y granular structure; slightly hard, very friable, Value: 4 or 5 dry; 2 or 3 moist slightly sticky, slightly plastic; few fine and Chroma: 2 or 3 medium and many very fine roots; neutral; clear Clay content: 18 to 27 percent smooth boundary. Content of rock fragments: 0 to 15 percent Bt1—4 to 9 inches; brown (10YR 5/3) clay loam, dark pebbles brown (10YR 3/3) moist; strong medium Electrical conductivity: 0 to 2 mmhos/cm subangular blocky structure; hard, very friable, Reaction: pH 6.6 to 7.3 moderately sticky, moderately plastic; few fine and common very fine roots; many very fine Bt horizons pores; common faint clay films on faces of peds Hue: 10YR or 2.5Y and in pores; neutral; clear smooth boundary. Value: 4, 5, or 6 dry; 3, 4, or 5 moist Bt2—9 to 17 inches; brown (10YR 5/3) sandy clay Chroma: 2 to 4 loam, brown (10YR 4/3) moist; weak coarse Texture: Clay loam or sandy clay loam prismatic structure parting to moderate medium Clay content: 27 to 35 percent subangular blocky; hard, friable, moderately Content of rock fragments: 0 to 15 percent sticky, slightly plastic; few fine and common very pebbles fine roots; few fine and many very fine pores; Electrical conductivity: 0 to 2 mmhos/cm common faint clay films on faces of peds, Reaction: pH 6.6 to 7.8 common distinct clay films in pores; slightly Bk1 horizon alkaline; clear wavy boundary. Hue: 10YR or 2.5Y Bk1—17 to 28 inches; pale brown (10YR 6/3) gravelly Value: 5, 6, 7, or 8 dry; 4, 5, 6, or 7 moist clay loam, grayish brown (10YR 5/3) moist; Chroma: 2 to 4 moderate fine and medium subangular blocky Texture: Sandy loam, loam, clay loam, or sandy structure; hard, friable, slightly sticky, slightly clay loam plastic; few very fine roots; common very fine Clay content: 10 to 30 percent pores; 15 percent pebbles; many fine masses of Content of rock fragments: 5 to 35 percent—0 to lime; strongly effervescent; moderately alkaline; 5 percent cobbles; 5 to 30 percent pebbles gradual wavy boundary. Calcium carbonate equivalent: 15 to 30 percent Bk2—28 to 36 inches; pale brown (10YR 6/3) gravelly Electrical conductivity: 0 to 2 mmhos/cm sandy loam, yellowish brown (10YR 5/4) moist; Reaction: pH 7.4 to 8.4 moderate medium subangular blocky structure; slightly hard, friable, slightly sticky, slightly plastic; Bk2 and Bk3 horizons few very fine roots; 25 percent pebbles; common Hue: 10YR or 2.5Y distinct lime coats on undersides of rock Value: 6, 7, or 8 dry; 4, 5, 6, or 7 moist fragments; common fine masses of lime; violently Chroma: 3 or 4 effervescent; moderately alkaline; gradual wavy Texture: Sandy loam, loam, or sandy clay loam boundary. Clay content: 10 to 30 percent Bk3—36 to 60 inches; very pale brown (10YR 7/3) Content of rock fragments: 5 to 35 percent—0 to gravelly sandy loam, pale brown (10YR 6/3) 5 percent cobbles; 5 to 30 percent pebbles moist; weak medium subangular blocky structure; Calcium carbonate equivalent: 15 to 30 percent soft, friable, nonsticky, nonplastic; few very fine Electrical conductivity: 0 to 2 mmhos/cm roots; 30 percent pebbles; common distinct lime Reaction: pH 7.4 to 8.4 158 Soil Survey

22A—Varney loam, 0 to 2 percent slopes Soils with lighter colored surface layers: 0 to 2 percent Soils with cobbly surface layers: 0 to 1 percent Setting Major Component Description Landform: Alluvial fans and stream terraces Slope: 0 to 2 percent Surface layer texture: Loam Mean annual precipitation: 12 to 15 inches Depth class: Very deep (more than 60 inches) Drainage class: Well drained Composition Dominant parent material: Alluvium Major Components Native plant cover type: Rangeland Varney and similar soils: 85 percent Flooding: None Available water capacity: Mainly 7.6 inches Minor Components Gerdrum and similar soils: 0 to 3 percent A typical soil description with range in Soils with very gravelly substratums: 0 to 3 percent characteristics is included, in alphabetical order, Yamacall and similar soils: 0 to 3 percent in this section. Delpoint and similar soils: 0 to 3 percent Soils with lighter colored surface layers: 0 to Management 2 percent For management information about this map unit, Soils with cobbly surface layers: 0 to 1 percent see appropriate sections in Part II of this publication. Major Component Description Surface layer texture: Loam Depth class: Very deep (more than 60 inches) 122C—Varney-Gerdrum complex, Drainage class: Well drained 2 to 8 percent slopes Dominant parent material: Alluvium Native plant cover type: Rangeland Setting Flooding: None Landform: Available water capacity: Mainly 7.6 inches • Varney—Alluvial fans and stream terraces • Gerdrum—Alluvial fans and stream terraces A typical soil description with range in Position on landform: characteristics is included, in alphabetical order, • Varney—Backslopes and footslopes in this section. • Gerdrum—Microlows Management Slope: • Varney—2 to 8 percent For management information about this map unit, • Gerdrum—2 to 8 percent see appropriate sections in Part II of this publication. Mean annual precipitation: 12 to 15 inches Composition 22C—Varney loam, 2 to 8 percent slopes Major Components Varney and similar soils: 50 percent Setting Gerdrum and similar soils: 35 percent Landform: Alluvial fans and stream terraces Minor Components Slope: 2 to 8 percent Gerdrum and similar soils: 0 to 3 percent Mean annual precipitation: 12 to 15 inches Soils with very gravelly substratums: 0 to 3 percent Composition Yamacall and similar soils: 0 to 3 percent Delpoint and similar soils: 0 to 3 percent Major Components Soils with gravelly surface layers: 0 to 2 percent Varney and similar soils: 85 percent Areas of slickspots: 0 to 1 percent Minor Components Major Component Description Gerdrum and similar soils: 0 to 3 percent Soils with very gravelly substratums: 0 to 3 percent Varney Yamacall and similar soils: 0 to 3 percent Surface layer texture: Loam Delpoint and similar soils: 0 to 3 percent Depth class: Very deep (more than 60 inches) Carter County, Montana—Part I 159

Drainage class: Well drained Bw—6 to 15 inches; dark grayish brown (10YR 4/2) Dominant parent material: Alluvium sandy loam, very dark grayish brown (10YR 3/2) Native plant cover type: Rangeland moist; moderate medium subangular blocky Flooding: None structure; slightly hard, very friable, slightly sticky, Available water capacity: Mainly 7.6 inches slightly plastic; common very fine, fine, medium, and coarse roots; few very fine pores; slightly Gerdrum acid; clear wavy boundary. Surface layer texture: Clay loam Bk1—15 to 21 inches; light brownish gray (10YR 6/2) Depth class: Very deep (more than 60 inches) sandy loam, dark grayish brown (10YR 4/2) Drainage class: Well drained moist; weak medium subangular blocky structure; Dominant parent material: Alluvium slightly hard, very friable, nonsticky, nonplastic; Native plant cover type: Rangeland few very fine roots; few very fine pores; few fine Flooding: None masses and threads of lime; 5 percent soft Salt affected: Saline within 30 inches channers; strongly effervescent; moderately Sodium affected: Sodic within 30 inches alkaline; gradual wavy boundary. Available water capacity: Mainly 5.8 inches Bk2—21 to 31 inches; white (2.5Y 8/2) sandy loam, light brownish gray (2.5Y 6/2) moist; massive; A typical soil description with range in slightly hard, friable, nonsticky, nonplastic; few characteristics is included, in alphabetical order, very fine roots; common fine masses of lime and in this section. few medium masses of lime; 25 percent soft channers; violently effervescent; moderately Management alkaline; clear wavy boundary. For management information about this map unit, Cr—31 to 60 inches; white (2.5Y 8/2) see appropriate sections in Part II of this publication. semiconsolidated, sandy sedimentary beds that crush to very fine sandy loam, light gray (2.5Y 7/2) moist. Vebar Series Range in Characteristics Depth class: Moderately deep (20 to 40 inches) Drainage class: Well drained Thickness of the mollic epipedon: 7 to 16 inches Permeability: Moderately rapid (2.0 to 6.0 inches/ Depth to the Bk horizon: 10 to 16 inches hour) Depth to the Cr horizon: 20 to 40 inches Landform: Sedimentary plains and hills Parent material: Semiconsolidated, sandy A horizon sedimentary beds Value: 3, 4, or 5 dry; 2 or 3 moist Slope range: 4 to 50 percent Chroma: 2 or 3 Annual precipitation: 15 to 17 inches Clay content: 10 to 18 percent Reaction: pH 6.1 to 7.8 Taxonomic Class: Coarse-loamy, mixed Typic Haploborolls Bw horizon Hue: 10YR or 2.5Y Typical Pedon Value: 4, 5, or 6 dry; 3 or 4 moist Vebar fine sandy loam, in an area of Belltower- Chroma: 2 to 4 Reeder-Vebar complex, 4 to 15 percent slopes, in an Texture: Fine sandy loam or sandy loam area of forestland, 500 feet south and 2,000 feet east Clay content: 10 to 18 percent of the northwest corner of sec. 4, T. 3 S., R. 61 E. Reaction: pH 6.1 to 8.4 Oi—1 inch to 0; slightly decomposed forest litter. Bk horizons A—0 to 6 inches; dark grayish brown (10YR 4/2) fine Hue: 10YR or 2.5Y sandy loam, very dark brown (10YR 2/2) moist; Value: 5, 6, 7, or 8 dry; 4, 5, or 6 moist weak fine subangular blocky structure; soft, very Chroma: 2 to 4 friable, nonsticky, nonplastic; common fine, Texture: Fine sandy loam or sandy loam medium, and coarse and many very fine roots; Clay content: 7 to 15 percent few very fine pores; slightly acid; clear smooth Calcium carbonate equivalent: 5 to 15 percent boundary. Reaction: pH 7.4 to 8.4 160 Soil Survey

Volborg Series Texture: Silty clay or clay Clay content: 40 to 50 percent Depth class: Shallow (10 to 20 inches) Electrical conductivity: 0 to 4 mmhos/cm Drainage class: Well drained Sodium adsorption ratio: 0 to 5; saline phase: 5 to Permeability: Slow (0.06 to 0.2 inch/hour) 13 Landform: Sedimentary plains and hills Reaction: pH 4.5 to 6.5 Parent material: Semiconsolidated shale C horizons Slope range: 2 to 60 percent Hue: 10YR or 2.5Y Annual precipitation: 12 to 15 inches Value: 5 or 6 dry; 4 or 5 moist Chroma: 1 to 3 Taxonomic Class: Clayey, montmorillonitic, acid, Texture: Silty clay loam, silty clay, or clay frigid, shallow Aridic Ustorthents Clay content: 35 to 50 percent Typical Pedon Electrical conductivity: 2 to 8 mmhos/cm; saline phase: 8 to 16 mmhos/cm Volborg clay, in an area of Neldore-Volborg clays, 4 to Sodium adsorption ratio: 0 to 13 15 percent slopes, in an area of rangeland, 2,000 feet Reaction: pH 3.6 to 5.5 north and 2,700 feet east of the southwest corner of sec. 3, T. 6 S., R. 59 E. Cr horizon Material: Semiconsolidated shale A—0 to 3 inches; light brownish gray (2.5Y 6/2) clay, Electrical conductivity: 8 to 16 mmhos/cm dark grayish brown (10YR 4/2) moist; weak Reaction: pH 3.6 to 5.5 coarse granular structure; very hard, friable, very sticky, very plastic; few fine and common very fine roots; slightly acid; abrupt smooth boundary. 98C—Volborg clay, 2 to 8 percent slopes C1—3 to 10 inches; light brownish gray (2.5Y 6/2) silty clay, grayish brown (2.5Y 5/2) moist; Setting moderate medium subangular blocky structure parting to moderate fine granular; very hard, Landform: Sedimentary plains friable, very sticky, very plastic; few fine and Slope: 2 to 8 percent common very fine roots; few very fine pores; very Mean annual precipitation: 12 to 15 inches strongly acid; clear wavy boundary. Composition C2—10 to 16 inches; light brownish gray (2.5Y 6/2) silty clay, grayish brown (2.5Y 5/2) moist; Major Components moderate medium subangular blocky structure Volborg and similar soils: 85 percent parting to moderate medium granular; extremely Minor Components hard, firm, very sticky, very plastic; few very fine Julin and similar soils: 0 to 4 percent roots; very strongly acid; clear wavy boundary. Neldore and similar soils: 0 to 4 percent Cr—16 to 60 inches; light gray (2.5Y 7/0) Very shallow clayey soils: 0 to 4 percent semiconsolidated shale, gray (2.5Y 5/0) moist. Moderately saline soils: 0 to 3 percent Range in Characteristics Major Component Description Soil temperature: 41 to 47 degrees F Surface layer texture: Clay Depth to bedrock: 10 to 20 inches; saline phase: 10 to Depth class: Shallow (10 to 20 inches) 14 inches Drainage class: Well drained Soil phases: Saline or warm Dominant parent material: Semiconsolidated shale Taxonomic note: Map unit 634E is a taxadjunct to residuum the Volborg series in order to join soils that have Native plant cover type: Rangeland an average soil temperature greater than Flooding: None 47 degrees F. Available water capacity: Mainly 1.9 inches A horizon Hue: 10YR or 2.5Y A typical soil description with range in Value: 5 or 6 dry; 4 or 5 moist characteristics is included, in alphabetical order, Chroma: 1 to 3 in this section. Carter County, Montana—Part I 161

Management Slope: • Volborg—8 to 25 percent For management information about this map unit, • Julin—8 to 25 percent see appropriate sections in Part II of this publication. Mean annual precipitation: 12 to 15 inches

198D—Volborg silty clay, saline, Composition 4 to 15 percent slopes Major Components Volborg and similar soils: 40 percent Setting Julin and similar soils: 35 percent Landform: Sedimentary plains and hills Rock outcrop: 15 percent Slope: 4 to 15 percent Minor Components Mean annual precipitation: 12 to 15 inches Teigen and similar soils: 0 to 3 percent Composition Neldore and similar soils: 0 to 2 percent Weingart and similar soils: 0 to 2 percent Major Components Marvan and similar soils: 0 to 2 percent Volborg and similar soils: 85 percent Orinoco and similar soils: 0 to 1 percent Minor Components Neldore and similar soils: 0 to 4 percent Major Component Description Soils that are calcareous throughout: 0 to 4 percent Very shallow clayey soils: 0 to 4 percent Volborg Bascovy and similar soils: 0 to 3 percent Surface layer texture: Clay Depth class: Shallow (10 to 20 inches) Major Component Description Drainage class: Well drained Surface layer texture: Silty clay Dominant parent material: Semiconsolidated shale Depth class: Shallow (10 to 20 inches) residuum Drainage class: Well drained Native plant cover type: Rangeland Dominant parent material: Semiconsolidated shale Flooding: None residuum Available water capacity: Mainly 1.9 inches Native plant cover type: Rangeland Flooding: None Julin Salt affected: Saline within 30 inches Surface layer texture: Silty clay loam Available water capacity: Mainly 1.4 inches Depth class: Moderately deep (20 to 40 inches) Drainage class: Well drained A typical soil description with range in Dominant parent material: Semiconsolidated shale characteristics is included, in alphabetical order, residuum in this section. Native plant cover type: Rangeland Flooding: None Management Available water capacity: Mainly 3.8 inches For management information about this map unit, see appropriate sections in Part II of this publication. Rock outcrop Definition: Consolidated acid shale 298E—Volborg-Julin-Rock outcrop complex, 8 to 25 percent slopes A typical soil description with range in characteristics is included, in alphabetical order, in this section. Setting Landform: Management • Volborg—Hills • Julin—Hills For management information about this map unit, • Rock outcrop—Hills see appropriate sections in Part II of this publication. 162 Soil Survey

398E—Volborg-Volborg, saline-Rock Management outcrop complex, 8 to 45 percent For management information about this map unit, slopes see appropriate sections in Part II of this publication.

Setting Landform: 634E—Volborg-Julin complex, warm, • Volborg—Hills 6 to 60 percent slopes • Volborg—Hills • Rock outcrop—Hills Setting Slope: • Volborg—8 to 45 percent Landform: • Volborg—8 to 45 percent • Volborg—Sedimentary plains and hills Mean annual precipitation: 12 to 15 inches • Julin—Sedimentary plains and hills Slope: Composition • Volborg—6 to 60 percent Major Components • Julin—6 to 25 percent Volborg and similar soils: 30 percent Mean annual precipitation: 12 to 15 inches Volborg and similar soils: 25 percent Rock outcrop: 20 percent Composition Minor Components Major Components Orinoco and similar soils: 0 to 4 percent Volborg and similar soils: 50 percent Neldore and similar soils: 0 to 4 percent Julin and similar soils: 35 percent Very shallow clayey soils: 0 to 4 percent Soils that are calcareous throughout: 0 to 3 percent Minor Components Very shallow clayey soils: 0 to 3 percent Major Component Description Marvan and similar soils: 0 to 3 percent Volborg Neldore and similar soils: 0 to 3 percent Surface layer texture: Clay Areas of shale outcroppings: 0 to 3 percent Depth class: Shallow (10 to 20 inches) Bascovy and similar soils: 0 to 2 percent Drainage class: Well drained Soils that have slopes less than 6 percent: 0 to Dominant parent material: Semiconsolidated shale 1 percent residuum Native plant cover type: Rangeland Major Component Description Flooding: None Available water capacity: Mainly 1.9 inches Volborg Surface layer texture: Clay Volborg Depth class: Shallow (10 to 20 inches) Surface layer texture: Silty clay Drainage class: Well drained Depth class: Shallow (10 to 20 inches) Dominant parent material: Semiconsolidated shale Drainage class: Well drained residuum Dominant parent material: Semiconsolidated shale Native plant cover type: Rangeland residuum Flooding: None Native plant cover type: Rangeland Available water capacity: Mainly 1.9 inches Flooding: None Salt affected: Saline within 30 inches Julin Available water capacity: Mainly 1.4 inches Surface layer texture: Silty clay loam Depth class: Moderately deep (20 to 40 inches) Rock outcrop Drainage class: Well drained Definition: Consolidated acid shale Dominant parent material: Semiconsolidated shale residuum A typical soil description with range in Native plant cover type: Rangeland characteristics is included, in alphabetical order, Flooding: None in this section. Available water capacity: Mainly 3.8 inches Carter County, Montana—Part I 163

A typical soil description with range in moderately sticky, moderately plastic; common characteristics is included, in alphabetical order, very fine roots; common fine masses of lime; in this section. strongly effervescent; moderately alkaline; clear smooth boundary. Management Bnyz—22 to 30 inches; light brownish gray (10YR For management information about this map unit, 6/2) silty clay loam, grayish brown (10YR 5/2) see appropriate sections in Part II of this publication. moist; moderate fine and medium subangular blocky structure; slightly hard, firm, moderately sticky, moderately plastic; few very fine roots; few W—Water very fine pores; many fine and medium nests and seams of gypsum crystals and other salts; Composition moderately alkaline, clear smooth boundary. Byz—30 to 36 inches; pale brown (10YR 6/3) silty Major Components clay loam, brown (10YR 5/3) moist; massive; Water: 100 percent slightly hard, friable, moderately sticky, Major Component Description moderately plastic; few very fine roots; few very fine pores; 55 percent soft shale fragments and Definition: Areas of open water 5 percent channers; few fine nests and seams of gypsum and other salts; moderately alkaline; Weingart Series clear smooth boundary. Cr—36 to 60 inches; very pale brown (10YR 7/3) Depth class: Moderately deep (20 to 40 inches) semiconsolidated shale, grayish brown (10YR Drainage class: Well drained 5/3) moist. Permeability: Very slow (<0.06 inch/hour) Landform: Sedimentary plains and hills Range in Characteristics Parent material: Semiconsolidated shale Soil temperature: 42 to 47 degrees F Slope range: 0 to 15 percent Depth to the Bkn horizon: 10 to 16 inches Annual precipitation: 12 to 15 inches Depth to the Bnyz horizon: 16 to 24 inches Depth to the Cr horizon: 20 to 40 inches Taxonomic Class: Fine, montmorillonitic Typic Soil phases: Warm Natriboralfs Other features: Some pedons are calcareous above Typical Pedon 10 inches. When the sodium adsorption ratio is less than 13, there is more exchangeable Weingart silty clay, 2 to 8 percent slopes, in an area magnesium plus sodium then calcium plus of rangeland, 1,200 feet south and 1,200 feet west of exchange acidity. the northeast corner of sec. 17, T. 8 S., R. 62 E. Taxonomic note: Map unit 620C is a taxadjunct to E—0 to 2 inches; light brownish gray (10YR 6/2) clay the Weingart series in order to join soils that have loam, dark grayish brown (10YR 4/2) moist; an average soil temperature greater than moderate thin platy structure; slightly hard, 47 degrees F. friable, moderately sticky, moderately plastic; E horizon many very fine roots; few fine and common very Hue: 10YR or 2.5Y fine pores; neutral; clear smooth boundary. Value: 5, 6, or 7 dry; 3, 4, 5, or 6 moist Btn—2 to 12 inches; pale brown (10YR 6/3) silty clay, Chroma: 2 or 3 brown (10YR 4/3) moist; moderate medium and Texture: Clay, clay loam, or silty clay when mixed coarse columnar structure parting to strong fine to 7 inches and medium subangular blocky; extremely hard, Clay content: 27 to 40 percent firm, moderately sticky, moderately plastic; many Content of rock fragments: 0 to 10 percent—0 to very fine roots; few very fine pores; many distinct 10 percent stones and cobbles; 0 to 5 percent clay films on faces of peds and in pores; hard shale; 0 to 5 percent soft shale moderately alkaline; clear smooth boundary. Reaction: pH 5.6 to 7.8 Bkn—12 to 22 inches; pale brown (10YR 6/3) silty clay loam, brown (10YR 5/3) moist; moderate Btn horizon medium prismatic structure parting to moderate Hue: 10YR or 2.5Y fine and medium subangular blocky; hard, firm, Value: 5 or 6 dry; 4 or 5 moist 164 Soil Survey

Chroma: 2 to 4 Neldore and similar soils: 0 to 3 percent Texture: Clay, silty clay, or sandy clay Soils that have slopes more than 8 percent: 0 to Clay content: 40 to 60 percent 3 percent Content of rock fragments: 0 to 10 percent—0 to Cabbart and similar soils: 0 to 2 percent 5 percent hard shale; 0 to 5 percent soft shale Areas of slickspots: 0 to 1 percent Electrical conductivity: 2 to 8 mmhos/cm Major Component Description Sodium adsorption ratio: 10 to 30 Reaction: pH 6.6 to 9.0 Surface layer texture: Silty clay Depth class: Moderately deep (20 to 40 inches) Bkn horizon Drainage class: Well drained Hue: 10YR, 2.5Y, or 5Y Dominant parent material: Semiconsolidated shale Value: 5, 6, or 7 dry; 4 or 5 moist residuum Chroma: 2 or 3 Native plant cover type: Rangeland Texture: Clay loam, silty clay, clay, sandy clay, or Flooding: None silty clay loam Salt affected: Saline within 30 inches Clay content: 35 to 55 percent Sodium affected: Sodic within 30 inches Content of rock fragments: 0 to 10 percent—0 to Available water capacity: Mainly 4.2 inches 5 percent hard shale; 0 to 5 percent soft shale Electrical conductivity: 4 to 16 mmhos/cm A typical soil description with range in Sodium adsorption ratio: 13 to 30 characteristics is included, in alphabetical order, Gypsum content: 0 to 1 percent in this section. Calcium carbonate equivalent: 5 to 15 percent Reaction: pH 7.9 to 9.0 Management Bnyz and Byz horizons For management information about this map unit, Hue: 10YR, 2.5Y, or 5Y see appropriate sections in Part II of this publication. Value: 5 or 6 dry; 4 or 5 moist Chroma: 1 to 4 Texture: Clay, silty clay, clay loam, or silty clay 620C—Weingart silty clay loam, warm, loam 0 to 6 percent slopes Clay content: 35 to 55 percent Content of rock fragments: 0 to 75 percent—0 to Setting 30 percent hard shale, 0 to 55 percent soft Landform: Sedimentary plains shale Slope: 0 to 6 percent Electrical conductivity: 4 to 16 mmhos/cm Mean annual precipitation: 12 to 15 inches Sodium adsorption ratio: 13 to 30 Gypsum content: 1 to 5 percent Composition Reaction: pH 7.9 to 9.0 Major Components Weingart and similar soils: 85 percent 15C—Weingart silty clay, Minor Components 2 to 8 percent slopes Gerdrum and similar soils: 0 to 3 percent Kobase and similar soils: 0 to 3 percent Setting Cabbart and similar soils: 0 to 3 percent Very shallow clayey soils: 0 to 3 percent Landform: Sedimentary plains Neldore and similar soils: 0 to 2 percent Slope: 2 to 8 percent Areas of slickspots: 0 to 1 percent Mean annual precipitation: 12 to 15 inches Major Component Description Composition Surface layer texture: Silty clay loam Major Components Depth class: Moderately deep (20 to 40 inches) Weingart and similar soils: 85 percent Drainage class: Well drained Minor Components Dominant parent material: Semiconsolidated shale Gerdrum and similar soils: 0 to 3 percent residuum Bascovy and similar soils: 0 to 3 percent Native plant cover type: Rangeland Carter County, Montana—Part I 165

Flooding: None BC—31 to 60 inches; light gray (10YR 7/2) loam, Salt affected: Saline within 30 inches grayish brown (10YR 5/2) moist; massive; slightly Sodium affected: Sodic within 30 inches hard, friable, slightly sticky, slightly plastic; few Available water capacity: Mainly 4.3 inches very fine roots; disseminated lime; strongly effervescent; moderately alkaline. A typical soil description with range in Range in Characteristics characteristics is included, in alphabetical order, in this section. Soil temperature: 42 to 47 degrees F Depth to the Bk horizon: 10 to 20 inches Management Other features: In some pedons, the material below For management information about this map unit, 40 inches consists of a strata of loam, silt loam, see appropriate sections in Part II of this publication. clay loam, and loamy sand. A horizon Yamacall Series Hue: 10YR, 2.5Y, or 5Y Value: 5 or 6 dry; 3, 4, or 5 moist Depth class: Very deep (more than 60 inches) Chroma: 2 to 4 Drainage class: Well drained Texture: Loam or silt loam Permeability: Moderate (0.6 to 2.0 inches/hour) Clay content: 18 to 27 percent Landform: Alluvial fans, stream terraces, and hills Content of rock fragments: 0 to 15 percent—0 to Parent material: Alluvium 5 percent cobbles, 0 to 10 percent pebbles Slope range: 0 to 25 percent Calcium carbonate equivalent: 0 to 5 percent Annual precipitation: 12 to 15 inches Effervescence: None to strongly Reaction: pH 6.6 to 8.4 Taxonomic Class: Fine-loamy, mixed, frigid Aridic Bw horizon Ustochrepts Hue: 10YR, 2.5Y, or 5Y Typical Pedon Value: 5, 6, or 7 dry; 4, 5, or 6 moist Chroma: 2 to 4 Yamacall loam, in an area of Delpoint-Yamacall Texture: Loam, clay loam, or silt loam loams, 8 to 15 percent slopes, in an area of Clay content: 18 to 30 percent rangeland, 1,000 feet south and 1,800 feet west of Content of rock fragments: 0 to 15 percent—0 to the northeast corner of sec. 28, T. 4 S., R. 55 E. 5 percent cobbles, 0 to 10 percent pebbles A—0 to 5 inches; light brownish gray (10YR 6/2) Reaction: pH 6.6 to 8.4 loam, dark grayish brown (10YR 4/2) moist; weak Bk horizon medium subangular blocky structure; slightly Hue: 10YR, 2.5Y, or 5Y hard, friable, slightly sticky, slightly plastic; many Value: 5, 6, 7, or 8 dry; 4, 5, or 6 moist very fine roots; few very fine pores; neutral; Chroma: 2 to 4 abrupt smooth boundary. Texture: Loam, clay loam, or silt loam Bw—5 to 15 inches; light gray (10YR 7/2) loam, Clay content: 18 to 30 percent grayish brown (10YR 5/2) moist; weak medium Content of rock fragments: 0 to 15 percent—0 to prismatic structure parting to moderate medium 5 percent cobbles, 0 to 10 percent pebbles subangular blocky; slightly hard, friable, slightly Electrical conductivity: 0 to 4 mmhos/cm sticky, slightly plastic; many very fine roots; few Calcium carbonate equivalent: 5 to 15 percent very fine and fine pores; disseminated lime; Reaction: pH 7.9 to 9.0 slightly effervescent; moderately alkaline; clear smooth boundary. BC horizon Bk—15 to 31 inches; light gray (10YR 7/2) loam, Hue: 10YR, 2.5Y, or 5Y grayish brown (10YR 5/2) moist; moderate Value: 5, 6, 7, or 8 dry; 4, 5, or 6 moist medium subangular blocky structure; slightly Chroma: 2 to 4 hard, friable, slightly sticky, slightly plastic; Texture: Loam, clay loam, or silt loam common very fine roots; few very fine pores; Clay content: 18 to 30 percent many fine masses of lime; violently effervescent; Content of rock fragments: 0 to 15 percent—0 to moderately alkaline; gradual wavy boundary. 5 percent cobbles, 0 to 10 percent pebbles 166 Soil Survey

Electrical conductivity: 0 to 4 mmhos/cm Minor Components Calcium carbonate equivalent: 5 to 10 percent Cabbart and similar soils: 0 to 3 percent Reaction: pH 7.9 to 9.0 Delpoint and similar soils: 0 to 3 percent Kremlin and similar soils: 0 to 3 percent Archin and similar soils: 0 to 3 percent 86A—Yamacall loam, Cambeth and similar soils: 0 to 2 percent 0 to 2 percent slopes Soils with gravelly surface layers: 0 to 1 percent Major Component Description Setting Surface layer texture: Loam Landform: Alluvial fans and stream terraces Depth class: Very deep (more than 60 inches) Slope: 0 to 2 percent Drainage class: Well drained Mean annual precipitation: 12 to 15 inches Dominant parent material: Alluvium Composition Native plant cover type: Rangeland Flooding: None Major Components Available water capacity: Mainly 9.7 inches Yamacall and similar soils: 85 percent Minor Components A typical soil description with range in Archin and similar soils: 0 to 3 percent characteristics is included, in alphabetical order, Cambeth and similar soils: 0 to 3 percent in this section. Delpoint and similar soils: 0 to 3 percent Management Kremlin and similar soils: 0 to 3 percent Busby and similar soils: 0 to 2 percent For management information about this map unit, Soils that are calcareous throughout: 0 to 1 percent see appropriate sections in Part II of this publication. Major Component Description Surface layer texture: Loam 86D—Yamacall loam, Depth class: Very deep (more than 60 inches) 8 to 15 percent slopes Drainage class: Well drained Dominant parent material: Alluvium Native plant cover type: Rangeland Setting Flooding: None Landform: Alluvial fans and stream terraces Available water capacity: Mainly 9.7 inches Slope: 8 to 15 percent Mean annual precipitation: 12 to 15 inches A typical soil description with range in characteristics is included, in alphabetical order, Composition in this section. Major Components Management Yamacall and similar soils: 90 percent For management information about this map unit, Minor Components see appropriate sections in Part II of this publication. Cabbart and similar soils: 0 to 2 percent Delpoint and similar soils: 0 to 2 percent 86C—Yamacall loam, Archin and similar soils: 0 to 2 percent 2 to 8 percent slopes Cambeth and similar soils: 0 to 2 percent Soils with darker colored surface layers: 0 to 1 percent Setting Soils that have slopes less than 8 percent: 0 to Landform: Alluvial fans and stream terraces 1 percent Slope: 2 to 8 percent Major Component Description Mean annual precipitation: 12 to 15 inches Surface layer texture: Loam Composition Depth class: Very deep (more than 60 inches) Major Components Drainage class: Well drained Yamacall and similar soils: 85 percent Dominant parent material: Alluvium Carter County, Montana—Part I 167

Native plant cover type: Rangeland Flooding: Rare Flooding: None Available water capacity: Mainly 9.7 inches Available water capacity: Mainly 9.7 inches A typical soil description with range in A typical soil description with range in characteristics is included, in alphabetical order, characteristics is included, in alphabetical order, in this section. in this section. 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.

186C—Yamacall-Havre loams, 186A—Yamacall-Havre loams, 2 to 8 percent slopes 0 to 2 percent slopes Setting Setting Landform: Landform: • Yamacall—Stream terraces • Yamacall—Stream terraces • Havre—Flood plains • Havre—Flood plains Slope: Slope: • Yamacall—2 to 8 percent • Yamacall—0 to 2 percent • Havre—2 to 4 percent • Havre—0 to 2 percent Mean annual precipitation: 12 to 15 inches Mean annual precipitation: 12 to 15 inches Composition Composition Major Components Major Components Yamacall and similar soils: 70 percent Yamacall and similar soils: 70 percent Havre and similar soils: 20 percent Havre and similar soils: 20 percent Minor Components Minor Components Delpoint and similar soils: 0 to 2 percent Harlake and similar soils: 0 to 2 percent Harlake and similar soils: 0 to 2 percent Kremlin and similar soils: 0 to 2 percent Kremlin and similar soils: 0 to 1 percent Cambeth and similar soils: 0 to 2 percent Archin and similar soils: 0 to 1 percent Areas of channels with steep slopes: 0 to 1 percent Areas of channels with steep slopes: 0 to 1 percent Poorly drained and ponded soils: 0 to 1 percent Poorly drained soils: 0 to 1 percent Major Component Description Major Component Description Yamacall Yamacall Surface layer texture: Loam Surface layer texture: Loam Depth class: Very deep (more than 60 inches) Depth class: Very deep (more than 60 inches) Drainage class: Well drained Drainage class: Well drained Dominant parent material: Alluvium Dominant parent material: Alluvium Native plant cover type: Rangeland Native plant cover type: Rangeland Flooding: None Flooding: None Available water capacity: Mainly 9.7 inches Available water capacity: Mainly 9.7 inches

Havre Havre Surface layer texture: Loam Surface layer texture: Loam Depth class: Very deep (more than 60 inches) Depth class: Very deep (more than 60 inches) Drainage class: Well drained Drainage class: Well drained Dominant parent material: Alluvium Dominant parent material: Alluvium Native plant cover type: Rangeland Native plant cover type: Rangeland 168 Soil Survey

Flooding: Rare Native plant cover type: Rangeland Available water capacity: Mainly 9.7 inches Flooding: None Available water capacity: Mainly 5.6 inches A typical soil description with range in characteristics is included, in alphabetical order, A typical soil description with range in in this section. characteristics is included, in alphabetical order, in this section. 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. 193C—Yamacall-Cambeth complex, 2 to 8 percent slopes 286C—Yamacall-Delpoint loams, 2 to 8 percent slopes Setting Setting Landform: • Yamacall—Alluvial fans and stream terraces Landform: • Cambeth—Sedimentary plains • Yamacall—Alluvial fans Slope: • Delpoint—Sedimentary plains • Yamacall—2 to 8 percent Slope: • Cambeth—2 to 8 percent • Yamacall—2 to 8 percent Mean annual precipitation: 12 to 15 inches • Delpoint—2 to 8 percent Mean annual precipitation: 12 to 15 inches Composition Composition Major Components Yamacall and similar soils: 50 percent Major Components Cambeth and similar soils: 35 percent Yamacall and similar soils: 50 percent Delpoint and similar soils: 35 percent Minor Components Delpoint and similar soils: 0 to 4 percent Minor Components Cabbart and similar soils: 0 to 3 percent Cabbart and similar soils: 0 to 4 percent Soils calcareous throughout: 0 to 3 percent Kremlin and similar soils: 0 to 4 percent Soils with darker colored surface layers: 0 to Soils that are calcareous throughout: 0 to 4 percent 3 percent Soils that have slopes more than 8 percent: 0 to Soils that have slopes more than 8 percent: 0 to 3 percent 2 percent Major Component Description Major Component Description Yamacall Yamacall Surface layer texture: Loam Surface layer texture: Loam Depth class: Very deep (more than 60 inches) Depth class: Very deep (more than 60 inches) Drainage class: Well drained Drainage class: Well drained Dominant parent material: Alluvium Dominant parent material: Alluvium Native plant cover type: Rangeland Native plant cover type: Rangeland Flooding: None Flooding: None Available water capacity: Mainly 9.7 inches Available water capacity: Mainly 9.7 inches Delpoint Cambeth Surface layer texture: Loam Surface layer texture: Silt loam Depth class: Moderately deep (20 to 40 inches) Depth class: Moderately deep (20 to 40 inches) Drainage class: Well drained Drainage class: Well drained Dominant parent material: Semiconsolidated, loamy Dominant parent material: Semiconsolidated, loamy sedimentary beds sedimentary beds Native plant cover type: Rangeland Carter County, Montana—Part I 169

Flooding: None Dominant parent material: Semiconsolidated, loamy Available water capacity: Mainly 4.7 inches sedimentary beds Native plant cover type: Rangeland A typical soil description with range in Flooding: None characteristics is included, in alphabetical order, Available water capacity: Mainly 2.2 inches in this section. A typical soil description with range in Management characteristics is included, in alphabetical order, For management information about this map unit, in this section. see appropriate sections in Part II of this publication. Management For management information about this map unit, 386E—Yamacall-Cabbart loams, see appropriate sections in Part II of this publication. 15 to 35 percent slopes

Setting 586D—Yamacall-Delpoint-Cabbart loams, Landform: 8 to 15 percent slopes • Yamacall—Hills • Cabbart—Hills Setting Position on landform: • Yamacall—Backslopes and footslopes Landform: • Cabbart—Shoulders and summits • Yamacall—Hills Slope: • Delpoint—Hills • Yamacall—15 to 25 percent • Cabbart—Hills • Cabbart—15 to 35 percent Slope: Mean annual precipitation: 12 to 15 inches • Yamacall—8 to 15 percent • Delpoint—8 to 15 percent Composition • Cabbart—8 to 15 percent Major Components Mean annual precipitation: 12 to 15 inches Yamacall and similar soils: 50 percent Composition Cabbart and similar soils: 35 percent Major Components Minor Components Yamacall and similar soils: 40 percent Delpoint and similar soils: 0 to 3 percent Delpoint and similar soils: 30 percent Blacksheep and similar soils: 0 to 3 percent Cabbart and similar soils: 15 percent Cambeth and similar soils: 0 to 3 percent Soils with gravelly or stony surfaces: 0 to 3 percent Minor Components Areas of rock outcrop: 0 to 2 percent Cambeth and similar soils: 0 to 4 percent Poorly drained soils: 0 to 1 percent Archin and similar soils: 0 to 3 percent Soils that have slopes more than 15 percent: 0 to Major Component Description 3 percent Yamacall Kremlin and similar soils: 0 to 3 percent Surface layer texture: Loam Soils that are calcareous throughout: 0 to 2 percent Depth class: Very deep (more than 60 inches) Drainage class: Well drained Major Component Description Dominant parent material: Alluvium Native plant cover type: Rangeland Yamacall Flooding: None Surface layer texture: Loam Available water capacity: Mainly 9.7 inches Depth class: Very deep (more than 60 inches) Drainage class: Well drained Cabbart Dominant parent material: Alluvium Surface layer texture: Loam Native plant cover type: Rangeland Depth class: Shallow (10 to 20 inches) Flooding: None Drainage class: Well drained Available water capacity: Mainly 9.7 inches 170 Soil Survey

Delpoint C—3 to 15 inches; light brownish gray (2.5Y 6/2) silty Surface layer texture: Loam clay loam, grayish brown (2.5Y 5/2) moist; Depth class: Moderately deep (20 to 40 inches) moderate fine and medium subangular blocky Drainage class: Well drained structure; hard, friable, very sticky, moderately Dominant parent material: Semiconsolidated, loamy plastic; common very fine roots; few fine and sedimentary beds common very fine pores; disseminated lime; Native plant cover type: Rangeland strongly effervescent; moderately alkaline; clear Flooding: None smooth boundary. Available water capacity: Mainly 4.7 inches Cr—15 to 60 inches; light brownish gray (2.5Y 6/2) semiconsolidated shale that crushes to silty clay Cabbart loam, grayish brown (2.5Y 5/2) moist. Surface layer texture: Loam Range in Characteristics Depth class: Shallow (10 to 20 inches) Drainage class: Well drained Depth to the Cr horizon: 10 to 20 inches Dominant parent material: Semiconsolidated, loamy Taxonomic note: Map unit 631D is a taxadjunct to sedimentary beds the Yawdim series in order to join soils that have Native plant cover type: Rangeland an average soil temperature greater than Flooding: None 47 degrees F. Available water capacity: Mainly 2.2 inches A horizon Hue: 10YR or 2.5Y A typical soil description with range in Value: 5 or 6 dry; 3 or 4 moist characteristics is included, in alphabetical order, Chroma: 1 or 2 in this section. Clay content: 27 to 40 percent Management Reaction: pH 6.6 to 7.8 For management information about this map unit, C horizon see appropriate sections in Part II of this publication. Hue: 10YR, 2.5Y, or 5Y Value: 5, 6, 7, or 8 dry; 4, 5, or 6 moist Chroma: 1 to 4 Yawdim Series Texture: Silty clay loam or silty clay Clay content: 35 to 50 percent Depth class: Shallow (10 to 20 inches) Calcium carbonate equivalent: 5 to 10 percent Drainage class: Well drained Reaction: pH 7.4 to 8.4 Permeability: Slow (0.06 to 0.2 inch/hour) Landform: Sedimentary plains and hills Parent material: Semiconsolidated shale Slope range: 4 to 70 percent 162D—Yawdim silty clay loam, Annual precipitation: 12 to 15 inches 4 to 15 percent slopes

Taxonomic Class: Clayey, montmorillonitic Setting (calcareous), frigid, shallow Aridic Ustorthents Landform: Sedimentary plains and hills Typical Pedon Slope: 4 to 15 percent Yawdim silty clay loam, 4 to 15 percent slopes, in an Mean annual precipitation: 12 to 15 inches area of rangeland, 1,200 feet north and 400 feet west Composition of the southeast corner of sec. 24, T. 8 N., R. 58 E. Major Components A—0 to 3 inches; grayish brown (2.5Y 5/2) silty clay Yawdim and similar soils: 85 percent loam, dark grayish brown (2.5Y 4/2) moist; moderate fine subangular blocky structure; Minor Components slightly hard, friable, very sticky, moderately Neldore and similar soils: 0 to 3 percent plastic; many very fine roots; few fine and Abor and similar soils: 0 to 3 percent common very fine pores; slightly alkaline; gradual Orinoco and similar soils: 0 to 3 percent wavy boundary. Very shallow clayey soils: 0 to 2 percent Carter County, Montana—Part I 171

Cabbart and similar soils: 0 to 2 percent Major Component Description Soils that have slopes less than 4 percent: 0 to Yawdim 2 percent Surface layer texture: Silty clay loam Major Component Description Depth class: Shallow (10 to 20 inches) Drainage class: Well drained Surface layer texture: Silty clay loam Dominant parent material: Semiconsolidated shale Depth class: Shallow (10 to 20 inches) residuum Drainage class: Well drained Native plant cover type: Rangeland Dominant parent material: Semiconsolidated shale Flooding: None residuum Available water capacity: Mainly 2.5 inches Native plant cover type: Rangeland Flooding: None Blacksheep Available water capacity: Mainly 2.5 inches Surface layer texture: Fine sandy loam Depth class: Shallow (10 to 20 inches) A typical soil description with range in Drainage class: Well drained characteristics is included, in alphabetical order, Dominant parent material: Semiconsolidated, sandy in this section. sedimentary beds Management Native plant cover type: Rangeland Flooding: None For management information about this map unit, Available water capacity: Mainly 2.3 inches see appropriate sections in Part II of this publication. Rock outcrop Definition: Consolidated sandstone and shale 262E—Yawdim-Blacksheep-Rock outcrop complex, 15 to 45 percent slopes A typical soil description with range in characteristics is included, in alphabetical order, Setting in this section. Landform: Management • Yawdim—Hills For management information about this map unit, • Blacksheep—Hills see appropriate sections in Part II of this publication. • Rock outcrop—Hills Position on landform: • Yawdim—Backslopes and footslopes Yegen Series • Blacksheep—Backslopes and shoulders • Rock outcrop—Shoulders and summits Depth class: Very deep (more than 60 inches) Slope: Drainage class: Well drained • Yawdim—15 to 45 percent Permeability: Moderate (0.6 to 2.0 inches/hour) • Blacksheep—15 to 45 percent Landform: Alluvial fans and stream terraces Mean annual precipitation: 12 to 15 inches Parent material: Alluvium Slope range: 2 to 15 percent Composition Annual precipitation: 15 to 17 inches Major Components Yawdim and similar soils: 40 percent Taxonomic Class: Fine-loamy, mixed Typic Blacksheep and similar soils: 30 percent Argiborolls Rock outcrop: 20 percent Typical Pedon Minor Components Yegen loam, 8 to 15 percent slopes, in an area of Bascovy and similar soils: 0 to 2 percent rangeland, 2,000 feet north and 1,500 feet east of Cabbart and similar soils: 0 to 2 percent the southwest corner of sec. 3, T. 4 S., R. 60 E. Very shallow loamy soils: 0 to 2 percent Orinoco and similar soils: 0 to 2 percent A—0 to 6 inches; dark grayish brown (10YR 4/2) Soils with stony surface layers: 0 to 1 percent loam, very dark grayish brown (10YR 3/2) moist; Soils that have slopes less than 15 percent: 0 to moderate thick platy structure; slightly hard, very 1 percent friable, slightly sticky, slightly plastic; common 172 Soil Survey

very fine and fine roots; few very fine pores; Clay content: 5 to 30 percent neutral; abrupt smooth boundary. Calcium carbonate equivalent: 5 to 15 percent Bt1—6 to 11 inches; dark grayish brown (2.5Y 4/2) Reaction: pH 7.9 to 8.4 clay loam, very dark grayish brown (2.5Y 3/2) moist; strong medium subangular blocky structure; hard, firm, moderately sticky, slightly 41C—Yegen loam, 2 to 8 percent slopes plastic; common very fine roots; few very fine pores; few distinct clay films on faces of peds and Setting in pores; neutral; clear smooth boundary. Landform: Alluvial fans and stream terraces Bt2—11 to 32 inches; light olive brown (2.5Y 5/4) clay Slope: 2 to 8 percent loam, olive brown (2.5Y 4/4) moist; moderate Mean annual precipitation: 15 to 17 inches coarse prismatic structure; hard, friable, slightly sticky, slightly plastic; few very fine roots; few very Composition fine pores; few distinct clay films on faces of peds Major Components and in pores; neutral; abrupt smooth boundary. Yegen and similar soils: 85 percent Bk1—32 to 38 inches; light yellowish brown (2.5Y 6/4) sandy clay loam, light olive brown (2.5Y 5/6) Minor Components moist; moderate coarse prismatic structure; hard, Reeder and similar soils: 0 to 4 percent very friable, slightly sticky, slightly plastic; few Moderately saline soils: 0 to 3 percent very fine roots; few fine and medium masses of Cabba and similar soils: 0 to 3 percent lime; strongly effervescent; moderately alkaline; Very deep sandy loam soils: 0 to 3 percent clear smooth boundary. Soils that have slopes less then 2 percent: 0 to Bk2—38 to 60 inches; pale yellow (2.5Y 7/3) sandy 2 percent loam, light olive brown (2.5Y 5/4) moist; weak Major Component Description coarse subangular blocky structure; slightly hard, very friable, slightly sticky, nonplastic; few very Surface layer texture: Loam fine roots; few fine masses of lime; strongly Depth class: Very deep (more than 60 inches) effervescent; moderately alkaline. Drainage class: Well drained Dominant parent material: Alluvium Range in Characteristics Native plant cover type: Rangeland Soil temperature: 41 to 47 degrees F Flooding: None Thickness of the mollic epipedon: 10 to 16 inches Available water capacity: Mainly 9.2 inches Depth to the Bk horizon: 24 to 40 inches A typical soil description with range in A horizon characteristics is included, in alphabetical order, Hue: 10YR or 2.5Y in this section. Value: 3 or 4 dry; 2 or 3 moist Chroma: 2 or 3 Management Clay content: 10 to 27 percent For management information about this map unit, Reaction: pH 6.6 to 7.3 see appropriate sections in Part II of this publication. Bt horizons Hue: 10YR or 2.5Y Value: 3, 4, or 5 dry; 2 to 4 moist 41D—Yegen loam, 8 to 15 percent slopes Chroma: 2 to 4 Texture: Sandy clay loam or clay loam Setting Clay content: 20 to 35 percent Landform: Alluvial fans Reaction: pH 6.6 to 7.3 Slope: 8 to 15 percent Bk horizons Mean annual precipitation: 15 to 17 inches Hue: 2.5Y or 5Y Composition Value: 5, 6, or 7 dry; 4, 5, or 6 moist Chroma: 3, 4, or 6 Major Components Texture: Sandy loam or sandy clay loam Yegen and similar soils: 85 percent Carter County, Montana—Part I 173

Minor Components Drainage class: Well drained Reeder and similar soils: 0 to 4 percent Dominant parent material: Alluvium Moderately saline soils: 0 to 3 percent Native plant cover type: Rangeland Cabba and similar soils: 0 to 3 percent Flooding: None Very deep sandy loam soils: 0 to 3 percent Available water capacity: Mainly 9.2 inches Soils that have slopes less than 8 percent: 0 to 2 percent Rentsac Surface layer texture: Sandy loam Major Component Description Depth class: Shallow (10 to 20 inches) Surface layer texture: Loam Drainage class: Well drained Depth class: Very deep (more than 60 inches) Dominant parent material: Sandstone residuum Drainage class: Well drained Native plant cover type: Rangeland Dominant parent material: Alluvium Flooding: None Native plant cover type: Rangeland Available water capacity: Mainly 1.4 inches Flooding: None Available water capacity: Mainly 9.2 inches A typical soil description with range in characteristics is included, in alphabetical order, A typical soil description with range in in this section. characteristics is included, in alphabetical order, Management in this section. 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. Ynot Series 141C—Yegen-Rentsac complex, Depth class: Very deep (more than 60 inches) 2 to 8 percent slopes Drainage class: Well drained Permeability: Moderately rapid (2.0 to 6.0 inches/ hour) Setting Landform: Alluvial fans and stream terraces Landform: Parent material: Alluvium and eolian deposits • Yegen—Alluvial fans Slope range: 2 to 15 percent • Rentsac—Bedrock-floored plains Annual precipitation: 12 to 15 inches Slope: • Yegen—2 to 8 percent Taxonomic Class: Coarse-loamy, mixed Aridic • Rentsac—2 to 8 percent Haploborolls Mean annual precipitation: 15 to 17 inches Typical Pedon Composition Ynot sandy loam, 2 to 8 percent slopes, in an area of Major Components rangeland, 40 feet south and 2,300 feet west of the Yegen and similar soils: 50 percent northeast corner of sec. 14, T. 4 S., R. 61 E. Rentsac and similar soils: 35 percent A—0 to 10 inches; grayish brown (10YR 5/2) sandy Minor Components loam, very dark grayish brown (10YR 3/2) moist; Reeder and similar soils: 0 to 4 percent moderate fine and medium granular structure; Cabba and similar soils: 0 to 4 percent loose, very friable, nonsticky, nonplastic; common Very deep sandy loam soils: 0 to 4 percent fine and many very fine roots; neutral; clear wavy Soils with darker colored surface layers: 0 to boundary. 3 percent Bw1—10 to 19 inches; brown (10YR 5/3) sandy loam, dark grayish brown (10YR 4/2) moist; weak fine Major Component Description and medium subangular blocky structure; soft, Yegen very friable, nonsticky, nonplastic; common very Surface layer texture: Loam fine and fine roots; few fine and common very fine Depth class: Very deep (more than 60 inches) pores; neutral; gradual smooth boundary. 174 Soil Survey

Bw2—19 to 31 inches; pale brown (10YR 6/3) sandy Composition loam, brown (10YR 4/3) moist; weak fine and Major Components medium subangular blocky structure; soft, very Ynot and similar soils: 85 percent friable, nonsticky, nonplastic; few fine and common very fine roots; common very fine pores Minor Components and few fine pores; neutral; gradual wavy Archin and similar soils: 0 to 4 percent boundary. Soils with gravelly surface layers: 0 to 3 percent C1—31 to 42 inches; pale brown (10YR 6/3) sandy Yamacall and similar soils: 0 to 3 percent loam, grayish brown (10YR 5/2) moist; weak fine Areas of blowouts: 0 to 3 percent and medium subangular blocky structure parting Soils with lighter colored surface layers: 0 to to weak fine granular; soft, very friable, nonsticky, 2 percent nonplastic; few very fine roots; neutral; gradual Major Component Description wavy boundary. C2—42 to 60 inches; light brownish gray (2.5Y 6/2) Surface layer texture: Sandy loam sandy loam, grayish brown (2.5Y 5/2) moist; Depth class: Very deep (more than 60 inches) massive; soft, very friable, nonsticky, nonplastic; Drainage class: Well drained few very fine roots; slightly alkaline. Dominant parent material: Alluvium or eolian material Native plant cover type: Rangeland Range in Characteristics Flooding: None Soil temperature: 42 to 47 degrees F Available water capacity: Mainly 7.7 inches Thickness of the mollic epipedon: 7 to 16 inches Other features: Some soils are calcareous below a A typical soil description with range in depth of 40 inches. characteristics is included, in alphabetical order, in this section. A horizon Hue: 10YR or 2.5Y Management Value: 2 or 3 moist For management information about this map unit, Chroma: 2 or 3 see appropriate sections in Part II of this publication. Clay content: 10 to 18 percent Reaction: pH 6.1 to 7.3 Bw horizons 59D—Ynot sandy loam, Hue: 10YR or 2.5Y 8 to 15 percent slopes Value: 5, 6, or 7 dry; 3, 4, 5, or 6 moist Chroma: 2 to 4 Setting Texture: Sandy loam or fine sandy loam Landform: Alluvial fans Clay content: 10 to 18 Slope: 8 to 15 percent Reaction: pH 6.1 to 7.3 Mean annual precipitation: 12 to 15 inches C horizons Composition Hue: 10YR, 2.5Y, or 5Y Value: 5, 6, or 7 dry; 4, 5, or 6 moist Major Components Chroma: 2 to 4 Ynot and similar soils: 85 percent Texture: Sandy loam or fine sandy loam Minor Components Clay content: 10 to 18 percent Archin and similar soils: 0 to 4 percent Reaction: pH 6.1 to 7.8 Soils with gravelly surface layers: 0 to 3 percent Yamacall and similar soils: 0 to 3 percent 59C—Ynot sandy loam, Areas of blowouts: 0 to 3 percent 2 to 8 percent slopes Soils with lighter colored surface layers: 0 to 2 percent Setting Major Component Description Landform: Alluvial fans and stream terraces Surface layer texture: Sandy loam Slope: 2 to 8 percent Depth class: Very deep (more than 60 inches) Mean annual precipitation: 12 to 15 inches Drainage class: Well drained Carter County, Montana—Part I 175

Dominant parent material: Alluvium or eolian material moderately sticky, moderately plastic; common Native plant cover type: Rangeland very fine roots; few very fine pores; common fine Flooding: None nests and seams of gypsum crystals; Available water capacity: Mainly 7.7 inches disseminated lime; slightly effervescent; moderately alkaline; clear smooth boundary. A typical soil description with range in By2—13 to 27 inches; light gray (2.5Y 7/2) silty clay characteristics is included, in alphabetical order, loam, grayish brown (2.5Y 5/2) moist; weak in this section. coarse subangular blocky structure; very hard, very firm, sticky and plastic; few very fine roots; Management many fine and medium nests of gypsum crystals; For management information about this map unit, disseminated lime; slightly effervescent; see appropriate sections in Part II of this publication. moderately alkaline; gradual smooth boundary. By3—27 to 60 inches; light gray (5Y 7/2) silty clay loam, olive gray (5Y 5/2) moist; massive; Zatoville Series extremely hard, extremely firm, moderately sticky, moderately plastic; few very fine roots; common Depth class: Very deep (more than 60 inches) reddish yellow (7.5YR 6/6) iron stains; common Drainage class: Well drained fine and medium nests of gypsum crystals; Permeability: Slow (0.06 to 0.2 inch/hour) disseminated lime; strongly effervescent; Landform: Alluvial fans and stream terraces moderately alkaline. Parent material: Alluvium Slope range: 2 to 8 percent Range in Characteristics Annual precipitation: 12 to 15 inches Soil temperature: 43 to 47 degrees F Taxonomic Class: Fine, montmorillonitic, frigid Aridic Depth to the By horizon: 13 to 24 inches Ustochrepts A horizon Typical Pedon Hue: 10YR or 2.5Y Value: 5 or 6 dry; 4 or 5 moist Zatoville silty clay loam, 2 to 8 percent slopes, in an Chroma: 2 or 3 area of rangeland, 2,200 feet north and 2,100 feet Clay content: 27 to 40 percent west of the southeast corner of sec. 3, T. 4 S., Electrical conductivity: 0 to 4 mmhos/cm R. 56 E. Reaction: pH 7.4 to 9.0 A—0 to 3 inches; light brownish gray (2.5Y 6/2) silty Bw horizon clay loam, dark grayish brown (2.5Y 4/2) moist; Hue: 10YR or 2.5Y moderate fine subangular blocky structure; hard, Value: 5 or 6 dry; 4 or 5 moist firm, moderately sticky, moderately plastic; many Chroma: 2 or 3 very fine roots; few very fine pores; disseminated Texture: Silty clay loam or silty clay lime; slightly effervescent; moderately alkaline; Clay content: 33 to 45 percent clear smooth boundary. Electrical conductivity: 0 to 4 mmhos/cm Bw—3 to 10 inches; light brownish gray (2.5Y 6/2) Reaction: pH 7.4 to 9.0 silty clay loam, dark grayish brown (2.5Y 4/2) moist; moderate medium prismatic structure By horizons parting to moderate fine subangular blocky; hard, Hue: 10YR, 2.5Y, or 5Y firm, moderately sticky, moderately plastic; many Value: 5, 6, or 7 dry; 4 or 5 moist very fine roots; few very fine pores; disseminated Chroma: 2 or 3 lime; slightly effervescent; moderately alkaline; Texture: Silty clay loam or silty clay clear smooth boundary. Clay content: 30 to 45 percent By1—10 to 13 inches; light gray (2.5Y 7/2) silty clay Electrical conductivity: 8 to 16 mmhos/cm loam, grayish brown (2.5Y 5/2) moist; moderate Sodium adsorption ratio: 13 to 30 medium prismatic structure parting to moderate Calcium carbonate equivalent: 5 to 10 percent fine and medium subangular blocky; hard, firm, Reaction: pH 7.9 to 9.0 176 Soil Survey

178C—Zatoville silty clay loam, Parent material: Eolian deposits 2 to 8 percent slopes Slope range: 4 to 15 percent Annual precipitation: 12 to 15 inches

Setting Taxonomic Class: Mixed, frigid Typic Ustipsamments Landform: Alluvial fans and stream terraces Typical Pedon Slope: 2 to 8 percent Zeona loamy fine sand, in an area of Zeona- Mean annual precipitation: 12 to 15 inches Blacksheep-Rock outcrop complex, 4 to 15 percent Composition slopes, in an area of rangeland, 1,500 feet south and 2,000 feet west of the northeast corner of sec. 32, Major Components T. 3 N., R. 55 E. Zatoville and similar soils: 85 percent Minor Components A—0 to 4 inches; yellowish brown (10YR 5/4) loamy Gerdrum and similar soils: 0 to 3 percent fine sand, brown (10YR 4/3) moist; single grain; Kobase and similar soils: 0 to 3 percent loose, nonsticky, nonplastic; common very fine Marvan and similar soils: 0 to 3 percent and fine roots; neutral; gradual irregular Areas of slickspots: 0 to 3 percent boundary. Soils that have slopes less than 2 percent: 0 to C1—4 to 16 inches; yellowish brown (10YR 5/4) 2 percent loamy fine sand, brown (10YR 4/3) moist; single Soils that have slopes more than 8 percent: 0 to grain; loose, nonsticky, nonplastic; common very 1 percent fine roots; neutral; gradual irregular boundary. C2—16 to 60 inches; light yellowish brown (10YR Major Component Description 6/4) loamy fine sand; brown (10YR 4/3) moist; Surface layer texture: Silty clay loam single grain; loose, nonsticky, nonplastic; few very Depth class: Very deep (more than 60 inches) fine roots; neutral. Drainage class: Well drained Range in Characteristics Dominant parent material: Alluvium Native plant cover type: Rangeland Soil temperature: 42 to 47 degrees F Flooding: None Other features: Colors throughout the control section Water table: Apparent are typically “salt and pepper” with lighter- and Salt affected: Saline within 30 inches darker-colored sand grains. Evidence of recent Sodium affected: Sodic within 30 inches wind action such as thin dark layers and Available water capacity: Mainly 7.7 inches variations in textures are observable in some pedons. Some pedons are calcareous below A typical soil description with range in 30 inches. characteristics is included, in alphabetical order, A horizon in this section. Hue: 5Y, 2.5Y, 10YR, or 7.5YR Management Value: 4, 5, 6, or 7 dry; 3, 4, 5, or 6 moist Chroma: 2 to 4 or 6 For management information about this map unit, Clay content: 0 to 10 percent see appropriate sections in Part II of this publication. Reaction: pH 5.6 to 7.8 C horizons Zeona Series Hue: 5Y, 2.5Y, 10YR, or 7.5YR Value: 5, 6, or 7 dry; 4 or 5 moist Depth class: Very deep (more than 60 inches) Chroma: 1 to 4 Drainage class: Excessively drained Texture: Loamy fine sand or fine sand Permeability: Rapid (6.0 to 20.0 inches/hour) Clay content: 0 to 10 percent Landform: Sand dunes Reaction: pH 6.1 to 8.4 Carter County, Montana—Part I 177

119D—Zeona-Blacksheep-Rock outcrop Drainage class: Excessively drained complex, 4 to 15 percent slopes Dominant parent material: Eolian deposits Native plant cover type: Rangeland Flooding: None Setting Available water capacity: Mainly 5.4 inches Landform: • Zeona—Sand dunes Blacksheep • Blacksheep—Sedimentary plains and hills Surface layer texture: Fine sandy loam • Rock outcrop—Hills Depth class: Shallow (10 to 20 inches) Slope: Drainage class: Well drained • Zeona—4 to 15 percent Dominant parent material: Semiconsolidated, sandy • Blacksheep—4 to 15 percent sedimentary beds Mean annual precipitation: 12 to 15 inches Native plant cover type: Rangeland Composition Flooding: None Available water capacity: Mainly 2.3 inches Major Components Zeona and similar soils: 40 percent Blacksheep and similar soils: 30 percent Rock outcrop Rock outcrop: 15 percent Definition: Consolidated sandstone Minor Components A typical soil description with range in Very shallow loamy soils: 0 to 4 percent characteristics is included, in alphabetical order, Cabbart and similar soils: 0 to 3 percent in this section. Archin and similar soils: 0 to 3 percent Areas of blowouts: 0 to 3 percent Management Areas with ponderosa pines: 0 to 2 percent Major Component Description For management information about this map unit, see appropriate sections in Part II of this publication. Zeona Surface layer texture: Loamy fine sand Depth class: Very deep (more than 60 inches)

179

References

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American Society for Testing and Materials (ASTM). 1988. Standard test method for 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.

Brown, P.L., and G.R. Carlson. 1990. Grain yields related to stored soil water and growing season rainfall. Montana Agricultural Experiment Station Special Report Number 35.

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Conner, R.C. 1993. Montana’s forest resources. U.S. Department of Agriculture, Forest Service, Intermountain Research Station Resource Bulletin INT-RB-81.

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.

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

Miller, M.R., W.M. Bermel, R.N. Bergantino, J.L. Sonderegger, P.M. Norbeck, and F.A. Schmidt. 1977. Compilation of hydrogeological data for southeastern Montana: Montana Bureau of Mines and Geology Open File Report 026.

Montana Department of State Lands, Division of Forestry, and U.S. Department of Agriculture, Forest Survey, Intermountain Forest and Range Experiment Station, Region 1. 1984. Timber resources of Eastern Montana. Working Circles 4, 5, 6, 7, and 8. 180

Myers, C.A. 1966. Yield tables for managed stands with special reference to the Black Hills. U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station Research Paper RM-RP-21.

O’Brien R.A., and D.C. Collins. 1991. Forest statistics for land outside national forests in Eastern Montana, 1989. U.S. Department of Agriculture, Intermountain Research Station Research Bulletin INT-RB-71.

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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.

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Soil Survey Staff. 1975. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. Natural Resources Conservation Service. U.S. Department of Agriculture Handbook 436.

Soil Survey Staff. 1990. Keys to soil taxonomy. 4th edition. U.S. Department of Agriculture, Natural Resources Conservation Service.

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Glossary

Ablation till. Loose, permeable till deposited during Available water capacity (available moisture the final downwasting of glacial ice. Lenses of capacity). The capacity of soils to hold water crudely sorted sand and gravel are common. available for use by most plants. It is commonly Aeration, soil. The exchange of air in soil with air defined as the difference between the amount of from the atmosphere. The air in a well-aerated soil water at field moisture capacity and the soil is similar to that in the atmosphere; the air in amount at wilting point. It is commonly expressed a poorly aerated soil is considerably higher in as inches of water per inch of soil. The capacity, carbon dioxide and lower in oxygen. in inches, in a 60-inch profile or to a limiting layer Aggregate, soil. Many fine particles held in a single is expressed as: mass or cluster. Natural soil aggregates, such as Very low ...... 0 to 3.75 granules, blocks, or prisms, are called peds. Low ...... 3.75 to 5.0 Clods are aggregates produced by tillage or Moderate ...... 5.0 to 7.5 logging. High ...... more than 7.5 Alkali (sodic) soil. (See Sodic (alkali) soil.) Alluvial fan. A body of alluvium, with overflow of Avalanche chute. The track or path formed by an water and debris flow deposits, whose surface avalanche. forms a segment of a cone that radiates Backslope. The geomorphic component that forms downslope from the point where the stream the steepest inclined surface and principal emerges from a narrow valley onto a less sloping element of many hillslopes. Backslopes in profile surface. Source uplands range in relief and areal are commonly steep and linear and descend to a extent from mountains to gullied terrains on footslope. In terms of gradational process, hillslopes. backslopes are erosional forms produced mainly Alluvium. Material, such as sand, silt, or clay, by mass wasting and running water. deposited on land by streams. Badland. Steep or very steep, commonly nonstony, Alpha,alpha-dipyridyl. A dye that when dissolved in barren land dissected by many intermittent 1N ammonium acetate is used to detect the drainage channels. Badland is most common in presence of reduced iron (Fe II) in the soil. A semiarid and arid regions where streams are positive reaction indicates a type of redox feature. entrenched in soft geologic material. Local relief Animal-unit-month (AUM). The amount of forage generally ranges from 25 to 500 feet. Runoff required by one mature cow of approximately potential is very high, and geologic erosion is 1,000 pounds weight, with or without a calf, for active. 1 month. Basal area. The area of a cross section of a tree, Aquic conditions. Current soil wetness generally referring to the section at breast height characterized by saturation, reduction, and redox and measured outside the bark. It is a measure of features. stand density, commonly expressed in square Area reclaim (in tables). An area difficult to reclaim feet. after the removal of soil for construction and other Basal till. Compact glacial till deposited beneath the uses. Revegetation and erosion control are ice. extremely difficult. 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 182 Soil Survey

to the contour) slope that, regardless of the Cable yarding. A method of moving felled trees to a lateral shape, forms an apron or wedge at the nearby central area for transport to a processing bottom of a hillside dominated by colluvium and facility. Most cable yarding systems involve use of slope-wash sediments (for example, slope 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 supported by standard crushed limestone, per accumulation of cobbles or gravel. In some unit area, with the same degree of distortion. blowouts, the water 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. Carter County, Montana—Part I 183

Chiseling. Tillage with an implement having one or Complex slope. Irregular or variable slope. Planning more soil-penetrating points that shatter or or establishing terraces, diversions, and other loosen hard, compacted layers to a depth below water-control structures on a complex slope is normal plow depth. difficult. 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 184 Soil Survey

compression. Terms describing consistence are Cutbanks cave (in tables). The walls of excavations defined in the “Soil Survey Manual” (Soil Survey tend to cave in or slough. Division Staff, 1962). Decreasers. The most heavily grazed climax range Consolidated sandstone. Sandstone that disperses plants. Because they are the most palatable, they within a few hours when fragments are placed in are the first to be destroyed by overgrazing. water. The fragments are extremely hard or very Deep soil. A soil that is 40 to 60 inches deep over hard when dry, are not easily crushed, and bedrock or to other material that restricts the cannot be textured by the usual field method. penetration of plant roots. Consolidated shale. Shale that disperses within a Deferred grazing. Postponing grazing or resting few hours when fragments are placed in water. grazing land for a prescribed period. The fragments are extremely hard or very hard Depth, soil. Generally, the thickness of the soil over when dry and are not easily crushed. bedrock. Very deep soils are more than 60 inches Contour stripcropping (or contour farming). deep over bedrock; deep soils, 40 to 60 inches; Growing crops in strips that follow the contour. moderately deep, 20 to 40 inches; shallow, 10 to Strips of grass or close-growing crops are 20 inches; and very shallow, less than 10 inches. alternated with strips of clean-tilled crops or Depth to rock (in tables). Bedrock is too near the summer fallow. surface for the specified use. Control section. The part of the soil on which Dip slope. A slope of the land surface, roughly classification is based. The thickness varies determined by and approximately conforming to among different kinds of soil, but for many it is the dip of the underlying bedrock. that part of the soil profile between depths of Diversion (or diversion terrace). A ridge of earth, 10 inches and 40 or 80 inches. generally a terrace, built to protect downslope Coprogenous earth (sedimentary peat). Fecal areas by diverting runoff from its natural course. material deposited in water by aquatic organisms. Divided-slope farming. A form of field stripcropping Corrosion. Soil-induced electrochemical or chemical in which crops are grown in a systematic action that dissolves or weakens concrete or arrangement of two strips, or bands, across the uncoated steel. slope to reduce the hazard of water erosion. One Cover crop. A close-growing crop grown primarily to strip is in a close-growing crop that provides improve and protect the soil between periods of protection from erosion, and the other strip is in a regular crop production, or a crop grown between crop that provides less protection from erosion. trees and vines in orchards and vineyards. This practice is used where slopes are not long Crop residue management. Returning crop residue enough to permit a full stripcropping pattern to be to the soil, which helps to maintain soil structure, used. organic matter content, and fertility and helps to Dominant trees. Trees whose crowns form the control erosion. general level of the forest canopy and that Cropping system. Growing crops according to a receive full light from above and from the sides. planned system of rotation and management Drainage class (natural). Refers to the frequency practices. and duration of periods of saturation or partial Cross-slope farming. Deliberately conducting saturation during soil formation, as opposed to farming operations on sloping farmland in such a altered drainage, which is commonly the result of way that tillage is across the general slope. artificial drainage or irrigation but may be caused Crown. The upper part of a tree or shrub, including by the sudden deepening of channels or the the living branches and their foliage. blocking of drainage outlets. Seven classes of Culmination of the mean annual increment natural soil drainage are recognized: (CMAI). The average annual increase per acre in Excessively drained.—These soils have very high the volume of a stand. Computed by dividing the and high hydraulic conductivity and a low water- total volume of the stand by its age. As the stand holding capacity. They are not suited to crop increases in age, the mean annual increment production unless irrigated. continues to increase until mortality begins to Somewhat excessively drained.—These soils reduce the rate of increase. The point where the have high hydraulic conductivity and a low water- stand reaches its maximum annual rate of growth holding capacity. Without irrigation, only a narrow is called the culmination of the mean annual range of crops can be grown, and yields are low. increment. Carter County, Montana—Part I 185

Well drained.—These soils have an intermediate Dune. A mound, ridge, or hill of loose, windblown water-holding capacity. They retain optimum granular material (generally sand), either bare or amounts of moisture, but they are not wet close covered with vegetation. enough to the surface or long enough during the Ecological site. An area where climate, soil, and growing season to adversely affect yields. relief are sufficiently uniform to produce a distinct Moderately well drained.—These soils are wet natural plant community. An ecological site is the close enough to the surface or long enough that product of all the environmental factors planting or harvesting operations or yields of responsible for its development. It is typified by an some field crops are adversely affected unless a association of species that differ from those on drainage system is installed. Moderately well- other ecological sites in kind and/or proportion of drained soils commonly have a layer with low species or in total production. hydraulic conductivity, a wet layer relatively high Eluviation. The movement of material in true solution in the profile, additions of water by seepage, or or colloidal suspension from one place to another some combination of these. within the soil. Soil horizons that have lost Somewhat poorly drained.—These soils are wet material through eluviation are eluvial; those that close enough to the surface or long enough that have received material are illuvial. planting or harvesting operations or crop growth Endosaturation. A type of saturation of the soil in is markedly restricted unless a drainage system which all horizons between the upper boundary is installed. Somewhat poorly drained soils of saturation and a depth of 2 meters are commonly have a layer with low hydraulic saturated. conductivity, a wet layer high in the profile, Eolian soil material. Earthy parent material additions of water through seepage, or a accumulated through wind action; commonly combination of these. refers to sandy material in dunes or to loess in Poorly drained.—These soils commonly are so blankets on the surface. wet, at or near the surface, during a considerable Ephemeral stream. A stream, or reach of a stream, part of the year that field crops cannot be grown that flows only in direct response to precipitation. under natural conditions. Poorly drained It receives no long-continued supply from melting conditions are caused by a saturated zone, a snow or other source, and its channel is above layer with low hydraulic conductivity, seepage, or the water table at all times. a combination of these. Episaturation. A type of saturation indicating a Very poorly drained.—These soils are wet to the perched water table in a soil in which saturated surface most of the time. The wetness prevents layers are underlain by one or more unsaturated the growth of important crops (except rice) unless layers within 2 meters of the surface. a drainage system is installed. Erosion. The wearing away of the land surface by Drainage, surface. Runoff, or surface flow of water, water, wind, ice, or other geologic agents and by from an area. such processes as gravitational creep. Drainageway. An area of ground at a lower elevation Erosion (geologic). Erosion caused by geologic than the surrounding ground and in which water processes acting over long geologic periods and collects and is drained to a closed depression or resulting in the wearing away of mountains and lake or to a drainageway at a lower elevation. A the building up of such landscape features as drainageway may or may not have distinctly flood plains and coastal plains. Synonym: natural incised channels at its upper reaches or erosion. throughout its course. Erosion (accelerated). Erosion much more rapid Drumlin. A low, smooth, elongated oval hill, mound, than geologic erosion, mainly as a result of or ridge of compact glacial till. The longer axis is human or animal activities or of a catastrophe in parallel to the path of the glacier and commonly nature, such as fire, that exposes the surface. has a blunt nose pointing in the direction from Erosion pavement. A layer of gravel or stones that which the ice approached. remains on the surface after fine particles are Duff. A generally firm organic layer on the surface of removed by sheet or rill erosion. mineral soils. It consists of fallen plant material Escarpment. A relatively continuous and steep slope that is in the process of decomposition and or cliff breaking the general continuity of more includes everything from the litter on the surface gently sloping land surfaces and resulting from to underlying pure humus. erosion or faulting. Synonym: scarp. 186 Soil Survey

Esker. A long, narrow, sinuous, steep-sided ridge equipment. Designated roads also serve as composed of irregularly stratified sand and gravel firebreaks. that were deposited by a subsurface stream First bottom. The normal flood plain of a stream, flowing between ice walls or through ice tunnels subject to frequent or occasional flooding. of a retreating glacier and that were left behind Flaggy soil material. Material that has, by volume, when the ice melted. Eskers range from less than 15 to 35 percent flagstones. Very flaggy soil a mile to more than 100 miles in length and from material has 35 to 60 percent flagstones, and 10 to 100 feet in height. extremely flaggy soil material has more than Even aged. Refers to a stand of trees in which only 60 percent flagstones. small differences in age occur between individual Flagstone. A thin fragment of sandstone, limestone, trees. A range of 20 years is allowed. slate, shale, or (rarely) schist 6 to 15 inches Excess fines (in tables). Excess silt and clay in the (15 to 38 centimeters) long. soil. The soil does not provide a source of gravel Flood plain. A nearly level alluvial plain that borders or sand for construction purposes. a stream and is subject to flooding unless Excess salt (in tables). Excess water-soluble salts in protected artificially. the soil that restrict the growth of most plants. Fluvial. Of or pertaining to rivers; produced by river Excess sodium (in tables). Excess exchangeable action, as a fluvial plain. sodium in the soil. The resulting poor physical Foothill. A steeply sloping upland that has relief of as properties restrict the growth of plants. much as 1,000 feet (300 meters) and fringes a Extrusive rock. Igneous rock derived from deep- mountain range or high-plateau escarpment. seated molten matter (magma) emplaced on the Footslope. The geomorphic component that forms earth’s surface. the inner, gently inclined surface at the base of a Fallow. Cropland left idle in order to restore hillslope. The surface profile is dominantly productivity through accumulation of moisture. concave. In terms of gradational processes, a Summer fallow is common in regions of limited footslope is a transitional zone between an rainfall where cereal grain is grown. The soil is upslope site of erosion (backslope) and a tilled for at least one growing season for weed downslope site of deposition (toeslope). control and decomposition of plant residue. Forb. Any herbaceous plant not a grass or a sedge. Fast intake (in tables). The rapid movement of water Forest cover. All trees and other woody plants into the soil. (underbrush) covering the ground in a forest. Fertility, soil. The quality that enables a soil to Forest type. A stand of trees similar in composition provide plant nutrients, in adequate amounts and and development because of given physical and in proper balance, for the growth of specified biological factors by which it may be differentiated plants when light, moisture, temperature, tilth, from other stands. and other growth factors are favorable. Fragipan. A loamy, brittle subsurface horizon low in Fibric soil material (peat). The least decomposed of porosity and content of organic matter and low or all organic soil material. Peat contains a large moderate in clay but high in silt or very fine sand. amount of well-preserved fiber that is readily A fragipan appears cemented and restricts roots. identifiable according to botanical origin. Peat has When dry, it is hard or very hard and has a higher the lowest bulk density and the highest water bulk density than the horizon or horizons above. content at saturation of all organic soil material. When moist, it tends to rupture suddenly under Field moisture capacity. The moisture content of a pressure rather than to deform slowly. soil, expressed as a percentage of the ovendry Frost action (in tables). Freezing and thawing of soil weight, after the gravitational, or free, water has moisture. Frost action can damage roads, drained away; the field moisture content 2 or 3 buildings and other structures, and plant roots. days after a soaking rain; also called normal field Genesis, soil. The mode of origin of the soil. Refers capacity, normal moisture capacity, or capillary especially to the processes or soil-forming factors capacity. responsible for the formation of the solum, or true Fine textured soil. Sandy clay, silty clay, or clay. soil, from the unconsolidated parent material. Firebreak. Area cleared of flammable material to Giant ripple mark. The undulating surface sculpture stop or help control creeping or running fires. It produced in noncoherent granular materials by also serves as a line from which to work and to currents of water and by the agitation of water in facilitate the movement of firefighters and Carter County, Montana—Part I 187

wave action during the draining of large glacial an obstacle to farm machinery and is too deep to lakes, such as Glacial Lake Missoula. be obliterated by ordinary tillage; a rill is of lesser Glacial drift. Pulverized and other rock material depth and can be smoothed over by ordinary transported by glacial ice and then deposited. tillage. Also, the sorted and unsorted material deposited Gypsum. A mineral consisting of hydrous calcium by streams flowing from glaciers. sulfate. Glacial outwash. Gravel, sand, and silt, commonly Habitat type. An aggregation of all land areas stratified, deposited by glacial meltwater. capable of producing similar climax plant Glacial till. Unsorted, nonstratified glacial drift communities. consisting of clay, silt, sand, and boulders Hard bedrock. Bedrock that cannot be excavated transported and deposited by glacial ice. except by blasting or by the use of special Glaciated uplands. Land areas that were previously equipment that is not commonly used in covered by continental or alpine glaciers and that construction. are at a higher elevation than the flood plain. Hardpan. A hardened or cemented soil horizon, or Glaciofluvial deposits. Material moved by glaciers layer. The soil material is sandy, loamy, or clayey and subsequently sorted and deposited by and is cemented by iron oxide, silica, calcium streams flowing from the melting ice. The carbonate, or other substance. deposits are stratified and occur as kames, Head out. To form a flower head. eskers, deltas, and outwash plains. Heavy metal. Inorganic substances that are solid at Glaciolacustrine deposits. Material ranging from ordinary temperatures and are not soluble in fine clay to sand derived from glaciers and water. They form oxides and hydroxides that are deposited in glacial lakes mainly by glacial basic. Examples are copper, iron, cadmium, zinc, meltwater. Many deposits are interbedded or manganese, lead, and arsenic. laminated. Hemic soil material (mucky peat). Organic soil Gleyed soil. Soil that formed under poor drainage, material intermediate in degree of decomposition resulting in the reduction of iron and other between the less decomposed fibric material and elements in the profile and in gray colors. the more decomposed sapric material. Grassed waterway. A natural or constructed High-residue crops. Such crops as small grain and waterway, typically broad and shallow, seeded to corn used for grain. If properly managed, residue grass as protection against erosion. Conducts from these crops can be used to control erosion surface water away from cropland. until the next crop in the rotation is established. Gravel. Rounded or angular fragments of rock These crops return large amounts of organic as much as 3 inches (2 millimeters to matter to the soil. 7.6 centimeters) in diameter. An individual Hill. A natural elevation of the land surface, rising as piece is a pebble. much as 1,000 feet above surrounding lowlands, Gravelly soil material. Soil that is 15 to 35 percent, commonly of limited summit area and having a by volume, rounded or angular rock fragments up well-defined outline; hillsides generally have to 3 inches (7.6 centimeters) in diameter. Very slopes of more than 8 percent. The distinction gravelly soil is 35 to 60 percent gravel, and between a hill and a mountain is arbitrary and is extremely gravelly soil is more than 60 percent dependent on local usage. gravel by volume. Horizon, soil. A layer of soil, approximately parallel to Grazeable forestland. Land capable of sustaining the surface, having distinct characteristics livestock grazing by producing forage of sufficient produced by soil-forming processes. In the quantity during one or more stages of secondary identification of soil horizons, an uppercase letter forest succession. represents the major horizons. Numbers or Green manure crop (agronomy). A soil-improving lowercase letters that follow represent crop grown to be plowed under in an early stage subdivisions of the major horizons. An of maturity or soon after maturity. explanation of the subdivisions is given in the Ground water. Water filling all the unblocked pores of “Soil Survey Manual” (Soil Survey Division Staff, the material below the water table. 1962). The major horizons of mineral soil are as Gully. A miniature valley with steep sides cut by follows: running water and through which water ordinarily O horizon.—An organic layer of fresh and runs only after rainfall. The distinction between a decaying plant residue. gully and a rill is one of depth. A gully generally is 188 Soil Survey

A horizon.—The mineral horizon at or near the Igneous rock. Rock formed by solidification from a surface in which an accumulation of humified molten or partially molten state. Major varieties organic matter is mixed with the mineral material. include plutonic and volcanic rock. Examples are Also, a plowed surface horizon, most of which andesite, basalt, and granite. was originally part of a B horizon. Illuviation. The movement of soil material from one E horizon.—The mineral horizon in which the horizon to another in the soil profile. Generally, main feature is loss of silicate clay, iron, material is removed from an upper horizon and aluminum, or some combination of these. deposited in a lower horizon. B horizon.—The mineral horizon below an A or Impervious soil. A soil through which water, air, or E horizon. The B horizon is in part a layer of roots penetrate slowly or not at all. No soil is transition from the overlying A to the underlying absolutely impervious to air and water all the C horizon. The B horizon also has distinctive time. characteristics, such as (1) accumulation of clay, Increasers. Species in the climax vegetation that sesquioxides, humus, or a combination of these; increase in amount as the more desirable plants (2) prismatic or blocky structure; (3) redder or are reduced by close grazing. Increasers browner colors than those in the A horizon; or commonly are the shorter plants and the less (4) a combination of these. palatable to livestock. C horizon.—The mineral horizon or layer, Infiltration. The downward entry of water into the excluding indurated bedrock, that is little affected immediate surface of soil or other material, as by soil-forming processes and does not have the contrasted with percolation, which is movement properties typical of the overlying soil material. of water through soil layers or material. The material of a C horizon may be either like or Infiltration capacity. The maximum rate at which unlike that in which the solum formed. If the water can infiltrate into a soil under a given set of material is known to differ from that in the solum, conditions. an Arabic numeral, commonly a 2, precedes the Infiltration rate. The rate at which water penetrates letter C. the surface of the soil at any given instant, Cr horizon.—Sedimentary beds of consolidated usually expressed in inches per hour. The rate sandstone and semiconsolidated and can be limited by the infiltration capacity of the consolidated shale. Generally, roots can soil or the rate at which water is applied at the penetrate this horizon only along fracture planes. surface. R layer.—Consolidated bedrock beneath the soil. Intake rate. The average rate of water entering the The bedrock commonly underlies a C horizon, soil under irrigation. Most soils have a fast initial but it can be directly below an A or a B horizon. 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 Intermittent stream. A stream, or reach of a stream, other extreme, are soils having a very slow that flows for prolonged periods only when it infiltration rate and thus a high runoff potential. receives ground-water discharge or long, They have a claypan or clay layer at or near the continued contributions from melting snow or surface, have a permanent high water table, or other surface and shallow subsurface sources. are shallow over nearly impervious bedrock or Invaders. On range, plants that encroach into an other material. A soil is assigned to two area and grow after the climax vegetation has hydrologic groups if part of the acreage is been reduced by grazing. Generally, plants artificially drained and part is undrained. invade following disturbance of the surface. Carter County, Montana—Part I 189

Irrigation. Application of water to soils to assist in is composed chiefly of rock fragments derived production of crops. Methods of irrigation are: from the valley walls by glacial abrasion and Basin.—Water is applied rapidly to nearly level plucking or by mass wasting. plains surrounded by levees or dikes. Leaching. The removal of soluble material from soil Border.—Water is applied at the upper end of a or other material by percolating water. strip in which the lateral flow of water is controlled Linear extensibility. Refers to the change in length by small earth ridges called border dikes, or of an unconfined clod as moisture content is borders. decreased from a moist to a dry state. Linear Controlled flooding.—Water is released at extensibility is used to determine the shrink-swell intervals from closely spaced field ditches and potential of soils. It is an expression of the volume distributed uniformly over the field. change between the water content of the clod at 1 1 Corrugation.—Water is applied to small, closely /3- or /10-bar tension (33kPa or 10kPa tension) spaced furrows or ditches in fields of close- and oven dryness. Volume change is influenced growing crops or in orchards so that it flows in by the amount and type of clay minerals in the only one direction. soil. The volume change is the percent change for Drip (or trickle).—Water is applied slowly and the whole soil. If it is expressed as a fraction, the under low pressure to the surface of the soil or resulting value is COLE, coefficient of linear into the soil through such applicators as emitters, extensibility. porous tubing, or perforated pipe. Liquid limit. The moisture content at which the soil Furrow.—Water is applied in small ditches made passes from a plastic to a liquid state. by cultivation implements. Furrows are used for Loam. Soil material that is 7 to 27 percent clay tree and row crops. particles, 28 to 50 percent silt particles, and less Sprinkler.—Water is sprayed over the soil surface than 52 percent sand particles. through pipes or nozzles from a pressure system. Loamy soil. Coarse sandy loam, sandy loam, fine Subirrigation.—Water is applied in open ditches sandy loam, very fine sandy loam, loam, silt or tile lines until the water table is raised enough loam, silt, clay loam, sandy clay loam, or silty clay to wet the soil. loam. Wild flooding.—Water, released at high points, is Loess. Fine-grained material, dominantly of silt-sized allowed to flow onto an area without controlled particles, deposited by wind. distribution. Low-residue crops. Such crops as corn used for Kame. A moundlike hill of glacial drift, composed silage, peas, beans, and potatoes. Residue from chiefly of stratified sand and gravel. these crops is not adequate to control erosion Kame terrace. A terracelike ridge consisting of until the next crop in the rotation is established. stratified sand and gravel that were deposited by These crops return little organic matter to the soil. a meltwater stream flowing between a melting Low strength. The soil is not strong enough to glacier and a higher valley wall or lateral moraine support loads. and that remained after the disappearance of the Marl. An earthy, unconsolidated deposit consisting ice. It is commonly pitted with kettles and has an chiefly of calcium carbonate mixed with clay in irregular ice-contact slope. approximately equal amounts. Lacustrine deposit. Material deposited in lake water Masses. Concentrations of substances in the soil and exposed when the water level is lowered or matrix that do not have a clearly defined the elevation of the land is raised. boundary with the surrounding soil material and Lake plain. A surface marking the floor of an extinct cannot be removed as a discrete unit. Common lake, filled in by well-sorted, stratified sediments. compounds making up masses are calcium Landslide. The rapid downhill movement of a mass carbonate, gypsum or other soluble salts, iron of soil and loose rock, generally when wet or oxide, and manganese oxide. Masses consisting saturated. The speed and distance of movement, of iron oxide or manganese oxide generally are as well as the amount of soil and rock material, considered a type of redox concentration. vary greatly. Mean annual increment (MAI). The average annual Large stones (in tables). Rock fragments 3 inches increase in volume of a tree during its entire life. (7.6 centimeters) or more across. Large stones Mechanical treatment. Use of mechanical adversely affect the specified use of the soil. equipment for seeding, brush management, and Lateral moraine. A ridgelike moraine carried on and other management practices. deposited at the side margin of a valley glacier. It 190 Soil Survey

Medium textured soil. Very fine sandy loam, loam, sides. A mountain can occur as a single, isolated silt loam, or silt. mass or in a group forming a chain or range. 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. Nutrient, plant. Any element taken in by a plant Moderately coarse textured soil. Coarse sandy essential to its growth. Plant nutrients are mainly loam, sandy loam, or fine sandy loam. nitrogen, phosphorus, potassium, calcium, Moderately deep soil. A soil that is 20 to 40 inches magnesium, sulfur, iron, manganese, copper, deep over bedrock or to other material that boron, and zinc obtained from the soil and restricts the penetration of plant roots. carbon, hydrogen, and oxygen obtained from the Moderately fine textured soil. Clay loam, sandy clay air and water. loam, or silty clay loam. Observed rooting depth. Depth to which roots have Mollic epipedon. A thick, dark, humus-rich surface been observed to penetrate. horizon (or horizons) that has high base Organic matter. Plant and animal residue in the soil saturation and pedogenic soil structure. It may in various stages of decomposition. The content include the upper part of the subsoil. of organic matter in the surface layer is described Moraine. An accumulation of glacial drift in a as follows: topographic landform of its own, resulting chiefly Very low ...... less than 0.5 percent from the direct action of glacial ice. Some types Low ...... 0.5 to 1.0 percent are lateral, recessional, and terminal. Moderately low ...... 1.0 to 2.0 percent Morphology, soil. The physical makeup of the soil, Moderate ...... 2.0 to 4.0 percent including the texture, structure, porosity, High ...... 4.0 to 8.0 percent consistence, color, and other physical, mineral, Very high ...... more than 8.0 percent and biological properties of the various horizons, and the thickness and arrangement of those Outwash plain. An extensive area of glaciofluvial horizons in the soil profile. material that was deposited by meltwater Mottling, soil. Areas of color that differ from the streams. matrix color. These colors are commonly Overstory. The trees in a forest that form the upper attributes retained from the geologic parent crown cover. material. (See Redox features for indications of Oxbow. The horseshoe-shaped channel of a former poor aeration and impeded drainage.) meander, remaining after the stream formed a Mountain. A natural elevation of the land surface, cutoff across a narrow meander neck. rising more than 1,000 feet above surrounding Pan. A compact, dense layer in a soil that impedes lowlands, commonly of restricted summit area the movement of water and the growth of roots. (relative to a plateau) and generally having steep Carter County, Montana—Part I 191

For example, hardpan, fragipan, claypan, Ponding. Standing water on soils in closed plowpan, and traffic pan. depressions. Unless the soils are artificially Parent material. The unconsolidated organic and drained, the water can be removed only by mineral material in which soil forms. percolation or evapotranspiration. Peat. Unconsolidated material, largely Poor filter (in tables). Because of rapid permeability undecomposed organic matter, that has or an impermeable layer near the surface, the soil accumulated under excess moisture. (See Fibric may not adequately filter effluent from a waste soil material.) disposal system. Ped. An individual natural soil aggregate, such as a Poorly graded. Refers to a coarse-grained soil or soil granule, a prism, or a block. material consisting mainly of particles of nearly Pedon. The smallest volume that can be called the same size. Because there is little difference in “a soil.” A pedon is three dimensional and large size of the particles, density can be increased enough to permit study of all horizons. Its area only slightly by compaction. ranges from about 10 to 100 square feet Potential natural community (PNC). The biotic (1 square meter to 10 square meters), depending community that would become established on an on the variability of the soil. ecological site if all successional sequences were Percolation. The movement of water through the soil. completed without interferences by man under Percs slowly (in tables). The slow movement of water the present environmental conditions. Natural through the soil, adversely affecting the specified disturbances are inherent in its development. The use. PNC may include acclimatized or naturalized Permeability. The quality of the soil that enables nonnative species. water or air to move downward through the Potential rooting depth (effective rooting depth). profile. Depth to which roots could penetrate if the Terms describing permeability are: content of moisture in the soil were adequate. The soil has no properties restricting the Very slow ...... less than 0.06 inch penetration of roots to this depth. Slow ...... 0.06 to 0.2 inch Prescribed burning. The application of fire to land Moderately slow ...... 0.2 to 0.6 inch under such conditions of weather, soil moisture, Moderate ...... 0.6 to 2.0 inches and time of day as presumably will result in the Moderately rapid ...... 2.0 to 6.0 inches intensity of heat and spread required to Rapid ...... 6.0 to 20 inches accomplish specific forest management, wildlife, Very rapid ...... more than 20 inches grazing, or fire hazard reduction purposes. Productivity, soil. The capability of a soil for pH value. A numerical designation of acidity and producing a specified plant or sequence of plants alkalinity in soil. (See Reaction, soil.) under specific management. Phase, soil. A subdivision of a soil series based on Profile, soil. A vertical section of the soil extending features that affect its use and management, through all its horizons and into the parent such as slope, stoniness, and flooding. material. Piping (in tables). Formation of subsurface tunnels Proper grazing use. Grazing at an intensity that or pipelike cavities by water moving through the maintains enough cover to protect the soil and soil. maintain or improve the quantity and quality of Plastic limit. The moisture content at which a soil the desirable vegetation. This practice increases changes from semisolid to plastic. the vigor and reproduction capacity of the key Plasticity index. The numerical difference between plants and promotes the accumulation of litter the liquid limit and the plastic limit. The range of and mulch necessary to conserve soil and water. moisture content within which the soil remains Quartzite, metamorphic. Rock consisting mainly of plastic. quartz that formed through recrystallization of Playa. The generally dry and nearly level lake plain quartz-rich sandstone or chert. that occupies the lowest parts of closed Quartzite, sedimentary. Very hard but depressional areas, such as those on unmetamorphosed sandstone consisting chiefly intermontane basin floors. Temporary flooding of quartz grains. occurs primarily in response to precipitation and Range condition. The present composition of the runoff. plant community on a range site in relation to the Plowpan. A compacted layer formed in the soil directly below the plowed layer. 192 Soil Survey

potential natural plant community for that site. change in hue or chroma within 30 minutes after (See Similarity index.) exposure to air as the iron is oxidized (Fe III). A Range site. (See Ecological site.) type of redox feature. Rangeland. Land on which the potential natural Regeneration. The new growth of a natural plant vegetation is predominantly grasses, grasslike community, developing from seed. plants, forbs, or shrubs suitable for grazing or Regolith. The unconsolidated mantle of weathered browsing. It includes natural grasslands, rock and soil material on the earth’s surface; the savannas, many wetlands, some deserts, loose earth material above the solid rock. tundras, and areas that support certain forb and Relict stream terrace. One of a series of platforms shrub communities. in or adjacent to a stream valley that formed prior Reaction, soil. A measure of acidity or alkalinity of a to the current stream system. soil, expressed in pH values. A soil that tests to Relief. The elevations or inequalities of a land pH 7.0 is described as precisely neutral in surface, considered collectively. reaction because it is neither acid nor alkaline. Residuum (residual soil material). Unconsolidated, The degrees of acidity or alkalinity, expressed as weathered or partly weathered mineral material pH values, are: that accumulated as consolidated rock Ultra acid ...... less than 3.5 disintegrated in place. Extremely acid ...... 3.5 to 4.4 Rill. A steep-sided channel resulting from accelerated Very strongly acid ...... 4.5 to 5.0 erosion. A rill generally is a few inches deep and Strongly acid ...... 5.1 to 5.5 not wide enough to be an obstacle to farm Moderately acid ...... 5.6 to 6.0 machinery. Slightly acid ...... 6.1 to 6.5 Riser. The relatively short, steeply sloping area below Neutral ...... 6.6 to 7.3 a terrace tread that grades to a lower terrace Slightly alkaline ...... 7.4 to 7.8 tread or base level. Moderately alkaline ...... 7.9 to 8.4 Riverwash. Unstable areas of sandy, silty, clayey, or Strongly alkaline ...... 8.5 to 9.0 gravelly sediments. These areas are flooded, Very strongly alkaline ...... 9.1 and higher washed, and reworked by rivers so frequently that they support little or no vegetation. Recessional moraine. A moraine formed during a Road cut. A sloping surface produced by mechanical temporary but significant halt in the retreat of a means during road construction. It is commonly glacier. on the uphill side of the road. Red beds. Sedimentary strata that are mainly red Rock fragments. Rock or mineral fragments having and are made up largely of sandstone and shale. a diameter of 2 millimeters or more; for example, Redox concentrations. Nodules, concretions, soft boulders, stones, cobbles, and gravel. masses, pore linings, and other features resulting Rock outcrop. Exposures of bare bedrock other than from the accumulation of iron or manganese lava flows and rock-lined pits. oxide. An indication of chemical reduction and Root zone. The part of the soil that can be oxidation resulting from saturation. penetrated by plant roots. Redox depletions. Low-chroma zones from which Rooting depth (in tables). Shallow root zone. The iron and manganese oxide or a combination of soil is shallow over a layer that greatly restricts iron and manganese oxide and clay has been roots. removed. These zones are indications of the Rubble land. Areas that have more than 90 percent chemical reduction of iron resulting from of the surface covered by stones or boulders. saturation. Voids contain no soil material and virtually no Redox features. Redox concentrations, redox vegetation other than lichens. The areas depletions, reduced matrices, a positive reaction commonly are at the base of mountain slopes, to alpha,alpha-dipyridyl, and other features but some are on mountain slopes as deposits of indicating the chemical reduction and oxidation of cobbles, stones, and boulders left by Pleistocene iron and manganese compounds resulting from glaciation or by periglacial phenomena. saturation. Runoff. The precipitation discharged into stream Reduced matrix. A soil matrix that has low chroma in channels from an area. The water that flows off situ because of chemically reduced iron (Fe II). the surface of the land without sinking into the The chemical reduction results from nearly soil is called surface runoff. Water that enters the continuous wetness. The matrix undergoes a soil before reaching surface streams is called Carter County, Montana—Part I 193

ground-water runoff or seepage flow from ground Sedimentary uplands. Land areas of bedrock water. formed from water- or wind-deposited sediments. Saline soil. A soil containing soluble salts in an They are higher on the landscape than the flood amount that impairs growth of plants. A saline soil plain. does not contain excess exchangeable sodium. Seepage (in tables). The movement of water through Salinity. The electrical conductivity of a saline soil. It soil. Seepage adversely affects the specified use. is expressed, in millimhos per centimeter, as Semiconsolidated sedimentary beds. Soft geologic follows: sediments that disperse when fragments are Nonsaline ...... 0 to 4 placed in water. The fragments are hard or very Slightly saline ...... 4 to 8 hard when dry. Determining the texture by the Moderately saline ...... 8 to 16 usual field method is difficult. Strongly saline ...... more than 16 Sequum. A sequence consisting of an illuvial horizon and the overlying eluvial horizon. (See Salty water (in tables). Water that is too salty for Eluviation.) consumption by livestock. Series, soil. A group of soils that have profiles that Sand. As a soil separate, individual rock or mineral are almost alike, except for differences in texture fragments from 0.05 to 2.0 millimeters in of the surface layer or of the underlying material. diameter. Most sand grains consist of quartz. As All the soils of a series have horizons that are a soil textural class, a soil that is 85 percent or similar in composition, thickness, and more sand and not more than 10 percent clay. arrangement. Sandstone. Sedimentary rock containing dominantly Shale. Sedimentary rock formed by the hardening of sand-sized particles. a clay deposit. Sandy soil. Sand or loamy sand. Shallow soil. A soil that is 10 to 20 inches deep over Sapric soil material (muck). The most highly bedrock or to other material that restricts the decomposed of all organic soil material. Muck penetration of plant roots. has the least amount of plant fiber, the highest Sheet erosion. The removal of a fairly uniform layer bulk density, and the lowest water content at of soil material from the land surface by the saturation of all organic soil material. action of rainfall and surface runoff. Saturation. Wetness characterized by zero or Shelterwood system. A forest management system positive pressure of the soil water. Under requiring the removal of a stand in a series of conditions of saturation, the water will flow from cuts so that regeneration occurs under a partial the soil matrix into an unlined auger hole. canopy. After regeneration, a final cut removes Sawlogs. Logs of suitable size and quality for the the shelterwood and allows the stand to develop production of lumber. in the open as an even-aged stand. The system is Scarification. The act of abrading, scratching, well suited to sites where shelter is needed for loosening, crushing, or modifying the surface to regeneration, and it can aid regeneration of the increase water absorption or to provide a more more intolerant tree species in a stand. tillable soil. Shoulder. The uppermost inclined surface at the top Scribner’s log rule. A method of estimating the of a hillside. It is the transitional zone from the number of board feet that can be cut from a log of backslope to the summit of a hill or mountain. The a given diameter and length. surface is dominantly convex in profile and Sedimentary plain. An extensive nearly level to erosional in origin. gently rolling or moderately sloping area that is Shrink-swell. The shrinking of soil when dry and the underlain by sedimentary bedrock and that has a swelling when wet. Shrinking and swelling can slope of 0 to 8 percent. damage roads, dams, building foundations, and Sedimentary rock. Rock made up of particles other structures. It can also 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 194 Soil Survey

(0.002 millimeters) to the lower limit of very fine soils, slickensides may occur at the bases of slip sand (0.05 millimeters). As a soil textural class, surfaces on the steeper slopes; on faces of soil that is 80 percent or more silt and less than blocks, prisms, and columns; and in swelling 12 percent clay. clayey soils, where there is marked change in Siltstone. Sedimentary rock made up of dominantly moisture content. silt-sized particles. Slickspot. A small area of soil having a puddled, Similar soils. Soils that share limits of diagnostic crusted, or smooth surface and an excess of criteria, behave and perform in a similar manner, exchangeable sodium. The soil generally is loamy 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 Slow refill (in tables). The slow filling of ponds, is represented by a curve. The basis of the curves resulting from restricted permeability in the soil. is the height of dominant or dominant and Small stones (in tables). Rock fragments less than codominant trees that are 100 years old or are 3 inches (7.6 centimeters) in diameter. Small 100 years old at breast height. stones adversely affect the specified use of the Site index. A designation of the quality of a forest site soil. based on the height of the dominant stand at an Sodic (alkali) soil. A soil having so high a degree arbitrarily chosen age. For example, if the of alkalinity (pH 8.5 or higher) or so high a average height attained by dominant or dominant percentage of exchangeable sodium (15 percent and codominant trees in a fully stocked stand at or more of the total exchangeable bases), or the age of 50 years is 75 feet, the site index is 75. both, that plant growth is restricted. Skid trails. Pathways along which logs are dragged Sodicity. The degree to which a soil is affected by to a common site for loading onto a logging truck. exchangeable sodium. Sodicity is expressed as a Slash. The branches, bark, treetops, reject logs, and sodium adsorption ratio (SAR) of a saturation broken or uprooted trees left on the ground after extract, or the ratio of Na+ to Ca++ + Mg++. The logging. degrees of sodicity and their respective ratios Slickens. Accumulations of fine textured material, are: such as material separated in placer-mine and Slight ...... less than 13:1 ore-mill operations. Slickens from ore mills Moderate ...... 13-30:1 commonly consist of freshly ground rock that has Strong ...... more than 30:1 undergone chemical treatment during the milling process. Sodium adsorption ratio (SAR). A measure of the Slickensides. Polished and grooved surfaces amount of sodium (Na) relative to calcium (Ca) produced by one mass sliding past another. In and magnesium (Mg) in the water extract from Carter County, Montana—Part I 195

saturated soil paste. It is the ratio of the Na Strath terrace. A surface cut formed by the erosion concentration divided by the square root of one- of hard or semiconsolidated bedrock and thinly half of the Ca + Mg concentration. mantled with stream deposits. Soft bedrock. Bedrock that can be excavated with Stream channel. The hollow bed where a natural trenching machines, backhoes, small rippers, and stream of surface water flows or may flow; the other equipment commonly used in construction. deepest or central part of the bed, formed by the Soil. A natural, three-dimensional body at the earth’s main current and covered more or less surface. It is capable of supporting plants and has continuously by water. properties resulting from the integrated effect of Stream terrace. One of a series of platforms in a climate and living matter acting on earthy parent stream valley, flanking and more or less parallel material, as conditioned by relief over periods of to the stream channel. It originally formed near time. the level of the stream and is the dissected Soil separates. Mineral particles less than remnants of an abandoned flood plain, 2 millimeters in equivalent diameter and ranging streambed, or valley floor that were produced between specified size limits. The names and during a former stage of erosion or deposition. sizes, in millimeters, of separates recognized in Stripcropping. Growing crops in a systematic the United States are as follows: arrangement of strips or bands that provide Very coarse sand ...... 2.0 to 1.0 vegetative barriers to soil blowing and water Coarse sand ...... 1.0 to 0.5 erosion. Medium sand ...... 0.5 to 0.25 Structure, soil. The arrangement of primary soil Fine sand ...... 0.25 to 0.10 particles into compound particles or aggregates. Very fine sand ...... 0.10 to 0.05 The principal forms of soil structure are platy Silt ...... 0.05 to 0.002 (laminated), prismatic (vertical axis of aggregates Clay ...... less than 0.002 longer than horizontal), columnar (prisms with rounded tops), blocky (angular or subangular), Solum. The upper part of a soil profile, above the and granular. Structureless soils are either single C horizon, in which the processes of soil grain (each grain by itself, as in dune sand) or formation are active. The solum in soil consists massive (the particles adhering without any of the A, E, and B horizons. Generally, the regular cleavage, as in many hardpans). characteristics of the material in these horizons Stubble mulch. Stubble or other crop residue left on are unlike those of the material below the solum. the soil or partly worked into the soil. It protects The living roots and plant and animal activities the soil from wind erosion and water erosion after are largely confined to the solum. harvest, during preparation of a seedbed for the Species. A single, distinct kind of plant or animal next crop, and during the early growing period of having certain distinguishing characteristics. the new crop. Stone line. A concentration of coarse fragments in a Subsoil. Technically, the B horizon; roughly, the part soil. Generally, it is indicative of an old weathered of the solum below plow depth. surface. In a cross section, the line may be one Subsoiling. Tilling a soil below normal plow depth, fragment or more thick. It generally overlies ordinarily to shatter or loosen a layer that is material that weathered in place and is overlain restrictive to roots. by recent sediment of variable thickness. Substratum. The part of the soil below the solum. Stones. Rock fragments 10 to 24 inches (25 to Subsurface layer. Any surface soil horizon (A, E, AB, 60 centimeters) in diameter if rounded or 15 to or EB) below the surface layer. 24 inches (38 to 60 centimeters) in length if 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 that crop. A practice common in semiarid regions, 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. 196 Soil Survey

Surface layer. The soil ordinarily moved in tillage, or or consists of till and that has a slope of 0 to its equivalent in uncultivated soil, ranging in 8 percent. depth from 4 to 10 inches (10 to 25 centimeters). Tilth, soil. The physical condition of the soil as Frequently designated as the “plow layer,” or the related to tillage, seedbed preparation, seedling “Ap horizon.” emergence, and root penetration. Tailwater. The water directly downstream of a Toeslope. The outermost inclined surface at the base structure. of a hill. Toeslopes are commonly gentle and Talus. Rock fragments of any size or shape, linear in profile. commonly coarse and angular, derived from and Too arid (in tables). The soil is dry most of the time, lying at the base of a cliff or very steep rock and vegetation is difficult to establish. slope. The accumulated mass of such loose, Topsoil. The upper part of the soil, which is the most broken rock formed chiefly by falling, rolling, or favorable material for plant growth. It is ordinarily sliding. rich in organic matter and is used to topdress Taxadjuncts. Soils that cannot be classified in a roadbanks, lawns, and land affected by mining. series recognized in the classification system. Trace elements. Chemical elements, for example, Such soils are named for a series they strongly zinc, cobalt, manganese, copper, and iron, in resemble and are designated as taxadjuncts to soils in extremely small amounts. They are that series because they differ in ways too small essential to plant growth. to be of consequence in interpreting their use Trafficability. The degree to which a soil is capable and behavior. of supporting vehicular traffic across a wide Terminal moraine. A belt of thick glacial drift that range in soil moisture conditions. generally marks the termination of important Tread. The relatively flat terrace surface that was cut glacial advances. or built by stream or wave action. Terrace. An embankment, or ridge, constructed Tuff. A compacted deposit that is 50 percent or more across sloping soils on the contour or at a slight volcanic ash and dust. angle to the contour. The terrace intercepts Understory. Any plants in a forest community that surface runoff so that water soaks into the soil or grow to a height of less than 5 feet. flows slowly to a prepared outlet. A terrace in a Upland. Land at a higher elevation, in general, than field generally is built so that the field can be the alluvial plain or stream terrace; land above farmed. A terrace intended mainly for drainage the lowlands along streams. has a deep channel that is maintained in Valley. An elongated depressional area primarily permanent sod. developed by stream action. Terrace (geologic). An old alluvial plain, ordinarily Valley fill. In glaciated regions, material deposited in flat or undulating, bordering a river, a lake, or the stream valleys by glacial meltwater. In sea. nonglaciated regions, alluvium deposited by Terracette. Small, irregular step-like forms on steep heavily loaded streams. hillslopes, especially in pasture, formed by creep Variegation. Refers to patterns of contrasting colors or erosion of surficial materials that may or may assumed to be inherited from the parent material not be induced by trampling of livestock such as rather than to be the result of poor drainage. sheep or cattle. Varve. A sedimentary layer or a lamina or sequence Texture, soil. The relative proportions of sand, silt, of laminae deposited in a body of still water within and clay particles in a mass of soil. The basic a year. Specifically, a thin pair of graded textural classes, in order of increasing proportion glaciolacustrine layers seasonally deposited, of fine particles, are sand, loamy sand, sandy usually by meltwater streams, in a glacial lake or loam, loam, silt loam, silt, sandy clay loam, clay other body of still water in front of a glacier. loam, silty clay loam, sandy clay, silty clay, and Very deep soil. A soil that is more than 60 inches clay. The sand, loamy sand, and sandy loam deep over bedrock or to other material that classes may be further divided by specifying restricts the penetration of plant roots. “coarse,” “fine,” or “very fine.” Very shallow soil. A soil that is less than 10 inches Thin layer (in tables). A layer of otherwise suitable deep over bedrock or to other material that soil material that is too thin for the specified use. restricts the penetration of plant roots. Till plain. An extensive, nearly level to gently rolling Water bars. Smooth, shallow ditches or depressional or moderately sloping area that is underlain by areas that are excavated at an angle across a Carter County, Montana—Part I 197

sloping road. They are used to reduce the Well graded. Refers to soil material consisting of downward velocity of water and divert it off and coarse-grained particles that are well distributed away from the road surface. Water bars can over wide range in size or diameter. Such soil easily be driven over if constructed properly. normally can be easily increased in density and Water-spreading. Diverting runoff from natural bearing properties by compaction. Contrasts with channels by means of a system of dams, dikes, poorly graded soil. or ditches and spreading it over relatively flat Wilting point (or permanent wilting point). The surfaces. moisture content of soil, on an ovendry basis, at Weathering. All physical and chemical changes which a plant (specifically a sunflower) wilts so produced in rocks or other deposits at or near the much that it does not recover when placed in a earth’s surface by atmospheric agents. These humid, dark chamber. changes result in disintegration and Windthrow. The action of uprooting and tipping over decomposition of the material. trees by the wind. NRCS Accessibility Statement

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