U.S. DEPARTMENT OF AGRICULTURE NATURAL RESOURCES CONSERVATION SERVICE 04/27/2000 NRCS TECHNICAL GUIDE SECTION II SOILS DATA FOR CONSERVATION PLANNING CA055-Napa County, California:Detailed Soil Map Legend ___________________________________________________________________________________________________________________ | | | | | | | Wind | | | Map Symbol | Component/ | Component | Depth | | | Erodi- |Hydro-| | and Map Unit Name | Local Phase | Percent | Inches | Kf 1/ | T 2/ | bility |logic | | | | | | | | Index 3/ |group | |________________________________|____________________|____________|____________|_________|_______|__________|______| | | | | | | | | | |100: | | | | | | | | | Aiken Loam, 2 To 15 Percent | Aiken | 85 | 0-8 | .37 | 3 | 48 | B | | Slopes | | | | | | | | | | | | 8-14 | .32 | | | | | | | | 14-44 | .28 | | | | | | | | 44-48 | --- | | | | | | | | | | | | | |101: | | | | | | | | | Aiken Loam, 15 To 30 Percent | Aiken | 85 | 0-8 | .37 | 3 | 48 | B | | Slopes | | | | | | | | | | | | 8-14 | .32 | | | | | | | | 14-44 | .28 | | | | | | | | 44-48 | --- | | | | | | | | | | | | | |102: | | | | | | | | | Aiken Loam, 30 To 50 Percent | Aiken | 85 | 0-8 | .37 | 3 | 48 | B | | Slopes | | | | | | | | | | | | 8-14 | .32 | | | | | | | | 14-44 | .28 | | | | | | | | 44-48 | --- | | | | | | | | | | | | | |103: | | | | | | | | | Bale Loam, 0 To 2 Percent | Bale | 85 | 0-24 | .37 | 5 | 48 | C | | Slopes | | | | | | | | | | | | 24-60 | .37 | | | | | | | | | | | | | |104: | | | | | | | | | Bale Clay Loam, 0 To 2 | Bale | 85 | 0-24 | .32 | 5 | 48 | C | | Percent Slopes | | | | | | | | | | | | 24-60 | .37 | | | | | | | | | | | | | |105: | | | | | | | | | Bale Clay Loam, 2 To 5 | Bale | 85 | 0-24 | .32 | 5 | 48 | C | | Percent Slopes | | | | | | | | | | | | 24-60 | .37 | | | | | | | | | | | | | |106: | | | | | | | | | Bale Complex, 0 To 2 Percent | Bale | 40 | 0-24 | .37 | 5 | 48 | C | | Slopes, Seeped | | | | | | | | | | | | 24-60 | .37 | | | | | | | | | | | | | | | Bale | 30 | 0-24 | .43 | 5 | 48 | C | | | | | 24-60 | .37 | | | | | | | | | | | | | |107: | | | | | | | | | Boomer Loam, 2 To 15 Percent | Boomer | 85 | 0-4 | .37 | 4 | 48 | B | | Slopes | | | | | | | | | | | | 4-44 | .32 | | | | | | | | 44-48 | --- | | | | | | | | | | | | | |108: | | | | | | | | | Boomer Gravelly Loam, 15 To | Boomer | 85 | 0-4 | .37 | 4 | 38 | B | | 30 Percent Slopes | | | | | | | | | | | | 4-44 | .32 | | | | | | | | 44-48 | --- | | | | | | | | | | | | | | | | | | | | | | |109: | | | | | | | | | Boomer Gravelly Loam, 30 To | Boomer | 85 | 0-4 | .37 | 4 | 48 | B | | 50 Percent Slopes | | | | | | | | | | | | 4-44 | .32 | | | | | | | | 44-48 | --- | | | | | | | | | | | | | |110: | | | | | | | | | Boomer-Forward-Felta Complex, | Boomer | 40 | 0-4 | .37 | 4 | 38 | B | | 30 To 50 Percent Slopes | | | | | | | | | | | | 4-44 | .32 | | | | | | | | 44-48 | --- | | | | | | | | | | | | | | | Forward | 35 | 0-4 | .37 | 3 | 38 | C | | | | | 4-35 | .24 | | | | | | | | 35-39 | --- | | | | | | | | | | | | | | | Felta | 15 | 0-7 | .37 | 5 | 38 | B | | | | | 7-26 | .32 | | | | | | | | 26-60 | .28 | | | | | | | | | | | | | |111: | | | | | | | | | Boomer-Forward-Felta Complex, | Boomer | 40 | 0-4 | .37 | 4 | 38 | B | | 5 To 30 Percent Slopes | | | | | | | | | | | | 4-44 | .32 | | | | | | | | 44-48 | --- | | | | | | | | | | | | | | | Forward | 35 | 0-4 | .37 | 3 | 38 | C | | | | | 4-35 | .24 | | | | | | | | 35-39 | --- | | | | | | | | | | | | | | | Felta | 20 | 0-7 | .37 | 5 | 38 | B | | | | | 7-26 | .32 | | | | | | | | 26-60 | .28 | | | | | | | | | | | | | |112: | | | | | | | | | Bressa-Dibble Complex, 5 To | Bressa | 65 | 0-10 | .37 | 3 | 48 | C | | 15 Percent Slopes | | | | | | | | | | | | 10-33 | .43 | | | | | | | | 33-37 | --- | | | | | | | | | | | | | | | Dibble | 25 | 0-9 | .55 | 3 | 48 | C | | | | | 9-34 | .32 | | | | | | | | 34-38 | --- | | | | | | | | | | | | | |113: | | | | | | | | | Bressa-Dibble Complex, 15 To | Bressa | 70 | 0-10 | .37 | 3 | 48 | C | | 30 Percent Slopes | | | | | | | | | | | | 10-33 | .43 | | | | | | | | 33-37 | --- | | | | | | | | | | | | | | | Dibble | 20 | 0-9 | .55 | 3 | 48 | C | | | | | 9-34 | .32 | | | | | | | | 34-38 | --- | | | | | | | | | | | | | |114: | | | | | | | | | Bressa-Dibble Complex, 30 To | Bressa | 70 | 0-10 | .37 | 3 | 48 | C | | 50 Percent Slopes | | | | | | | | | | | | 10-33 | .43 | | | | | | | | 33-37 | --- | | | | | | | | | | | | | | | | | | | | | | | | Dibble | 15 | 0-9 | .55 | 3 | 48 | C | | | | | 9-34 | .32 | | | | | | | | 34-38 | --- | | | | | | | | | | | | | |115: | | | | | | | | | Bressa-Dibble Complex, 50 To | Bressa | 75 | 0-10 | .37 | 3 | 48 | C | | 75 Percent Slopes | | | | | | | | | | | | 10-33 | .43 | | | | | | | | 33-37 | --- | | | | | | | | | | | | | | | Dibble | 15 | 0-9 | .55 | 3 | 48 | C | | | | | 9-34 | .32 | | | | | | | | 34-38 | --- | | | | | | | | | | | | | |116: | | | | | | | | | Clear Lake Clay, Drained | Clear Lake | 85 | 0-32 | .24 | 5 | 86 | D | | | | | 32-69 | .24 | | | | | | | | | | | | | |117: | | | | | | | | | Clear Lake Clay, Overwashed | Clear Lake | 85 | 0-18 | .32 | 5 | 86 | D | | | | | 18-69 | .24 | | | | | | | | | | | | | |118: | | | | | | | | | Cole Silt Loam, 0 To 2 | Cole | 85 | 0-8 | .37 | 5 | 48 | C | | Percent Slopes | | | | | | | | | | | | 8-64 | .32 | | | | | | | | | | | | | |119: | | | | | | | | | Cole Silt Loam, 2 To 5 | Cole | 85 | 0-8 | .37 | 5 | 48 | C | | Percent Slopes | | | | | | | | | | | | 8-64 | .32 | | | | | | | | | | | | | |120: | | | | | | | | | Contra Costa Loam, 5 To 15 | Contra Costa | 85 | 0-5 | .37 | 3 | 48 | C | | Percent Slopes | | | | | | | | | | | | 5-22 | .28 | | | | | | | | 22-34 | .37 | | | | | | | | 34-38 | --- | | | | | | | | | | | | | |121: | | | | | | | | | Contra Costa Gravelly Loam, 5 | Contra Costa | 85 | 0-5 | .37 | 2 | 48 | C | | To 15 Percent Slopes | | | | | | | | | | | | 5-34 | .37 | | | | | | | | 34-38 | --- | | | | | | | | | | | | | |122: | | | | | | | | | Coombs Gravelly Loam, 0 To 2 | Coombs | 85 | 0-14 | .37 | 5 | 38 | B | | Percent Slopes | | | | | | | | | | | | 14-54 | .37 | | | | | | | | 54-60 | .28 | | | | | | | | | | | | | |123: | | | | | | | | | Coombs Gravelly Loam, 2 To 5 | Coombs | 85 | 0-14 | .37 | 5 | 38 | B | | Percent Slopes | | | | | | | | | | | | 14-54 | .37 | | | | | | | | 54-60 | .28 | | | | | | | | | | | | | | | | | | | | | | |124: | | | | | | | | | Cortina Very Gravelly Loam, 0 | Cortina | 85 | 0-11 | .24 | 5 | 38 | A | | To 5 Percent Slopes | | | | | | | | | | | | 11-60 | .17 | | | | | | | | | | | | | |125: | | | | | | | | | Cortina Very Stony Loam, 0 To | Cortina | 85 | 0-21 | .24 | 5 | 38 | A | | 5 Percent Slopes | | | | | | | | | | | | 21-60 | .20 | | | | | | | | | | | | | |126: | | | | | | | | | Diablo Clay, 5 To 9 Percent | Diablo | 85 | 0-60 | .24 | 5 | 86 | D | | Slopes | | | | | | | | | | | | 60-64 | --- | | | | | | | | | | | | | |127: | | | | | | | | | Diablo Clay, 9 To 15 Percent | Diablo | 85 | 0-60 | .24 | 5 | 86 | D | | Slopes | | | | | | | | | | | | 60-64 | --- | | | | | | | | | | | | | |128: | | | | | | | | | Diablo Clay, 15 To 30 Percent | Diablo | 85 | 0-60 | .24 | 5 | 86 | D | | Slopes | | | | | | | | | | | | 60-64 | --- | | | | | | | | | | | | | |129: | | | | | | | | | Diablo Clay, 30 To 50 Percent | Diablo | 85 | 0-60 | .24 | 5 | 86 | D | | Slopes | | | | | | | | | | | | 60-64 | --- | | | | | | | | | | | | | |130: | | | | | | | | | Egbert Silty Clay Loam | Egbert | 85 | 0-33 | .28 | 5 | 38 | D | | | | | 33-60 | .24 | | | | | | | | | | | | | |131: | | | | | | | | | Fagan Clay Loam, 5 To 15 | Fagan | 85 | 0-16 | .32 | 4 | 86 | C | | Percent Slopes | | | | | | | | | | | | 16-28 | .37 | | | | | | | | 28-46 | .37 | | | | | | | | 46-50 | --- | | | | | | | | | | | | | |132: | | | | | | | | | Fagan Clay Loam, 15 To 30 | Fagan | 85 | 0-16 | .32 | 4 | 86 | C | | Percent Slopes | | | | | | | | | | | | 16-28 | .37 | | | | | | | | 28-46 | .37 | | | | | | | | 46-50 | --- | | | | | | | | | | | | | |133: | | | | | | | | | Fagan Clay Loam, 30 To 50 | Fagan | 85 | 0-16 | .32 | 4 | 86 | C | | Percent Slopes | | | | | | | | | | | | 16-28 | .37 | | | | | | | | 28-46 | .37 | | | | | | | | 46-50 | --- | | | | | | | | | | | | | | | | | | | | | | |134: | | | | | | | | | Fagan Clay Loam, 30 To 50 | Fagan | 85 | 0-16 | .32 | 4 | 86 | C | | Percent Slopes, Slipped | | | | | | | | | | | | 16-28 | .37 | | | | | | | | 28-46 | .37 | | | | | | | | 46-50 | --- | | | | | | | | | | | | | |135: | | | | | | | | | Felton Gravelly Loam, 15 To | Felton | 85 | 0-10 | .43 | 3 | 38 | C | | 30 Percent Slopes | | | | | | | | | | | | 10-33 | .32 | | | | | | | | 33-37 | --- | | | | | | | | | | | | | |136: | | | | | | | | | Felton Gravelly Loam, 30 To | Felton | 85 | 0-10 | .43 | 3 | 38 | C | | 50 Percent Slopes | | | | | | | | | | | | 10-33 | .32 | | | | | | | | 33-37 | --- | | | | | | | | | | | | | |137: | | | | | | | | | Felton Gravelly Loam, 50 To | Felton | 85 | 0-10 | .43 | 3 | 38 | C | | 75 Percent Slopes | | | | | | | | | | | | 10-33 | .32 | | | | | | | | 33-37 | --- | | | | | | | | | | | | | |138: | | | | | | | | | Forward Gravelly Loam, 2 To 9 | Forward | 85 | 0-4 | .37 | 3 | 48 | C | | Percent Slopes | | | | | | | | | | | | 4-35 | .24 | | | | | | | | 35-39 | --- | | | | | | | | | | | | | |139: | | | | | | | | | Forward Gravelly Loam, 9 To | Forward | 85 | 0-4 | .37 | 3 | 48 | C | | 30 Percent Slopes | | | | | | | | | | | | 4-35 | .24 | | | | | | | | 35-39 | --- | | | | | | | | | | | | | |140: | | | | | | | | | Forward Gravelly Loam, 30 To | Forward | 85 | 0-4 | .37 | 3 | 48 | C | | 75 Percent Slopes | | | | | | | | | | | | 4-35 | .24 | | | | | | | | 35-39 | --- | | | | | | | | | | | | | |141: | | | | | | | | | Forward-Kidd Complex, 50 To | Forward | 60 | 0-4 | .37 | 3 | 48 | C | | 75 Percent Slopes | | | | | | | | | | | | 4-35 | .24 | | | | | | | | 35-39 | --- | | | | | | | | | | | | | | | Kidd | 30 | 0-14 | .37 | 2 | 56 | D | | | | | 14-18 | --- | | | | | | | | | | | | | |142: | | | | | | | | | Guenoc Loam, 30 To 50 Percent | Guenoc | 85 | 0-12 | .37 | 2 | 48 | C | | Slopes | | | | | | | | | | | | 12-30 | .37 | | | | | | | | 30-34 | --- | | | | | | | | | | | | | | | | | | | | | | |143: | | | | | | | | | Guenoc-Rock Outcrop Complex, | Guenoc | 60 | 0-12 | .37 | 2 | 48 | C | | 5 To 30 Percent Slopes | | | | | | | | | | | | 12-30 | .37 | | | | | | | | 30-34 | --- | | | | | | | | | | | | | | | Rock Outcrop | 30 | --- | --- | - | --- | --- | | | | | | | | | | |144: | | | | | | | | | Guenoc-Rock Outcrop Complex, | Guenoc | 50 | 0-12 | .37 | 2 | 48 | C | | 30 To 75 Percent Slopes | | | | | | | | | | | | 12-30 | .37 | | | | | | | | 30-34 | --- | | | | | | | | | | | | | | | Rock Outcrop | 40 | --- | --- | - | --- | --- | | | | | | | | | | |145: | | | | | | | | | Haire Loam, 0 To 2 Percent | Haire | 85 | 0-22 | .37 | 5 | 48 | C | | Slopes | | | | | | | | | | | | 22-27 | .37 | | | | | | | | 27-45 | .24 | | | | | | | | 45-60 | .37 | | | | | | | | | | | | | |146: | | | | | | | | | Haire Loam, 2 To 9 Percent | Haire | 85 | 0-22 | .37 | 5 | 48 | C | | Slopes | | | | | | | | | | | | 22-27 | .37 | | | | | | | | 27-45 | .24 | | | | | | | | 45-60 | .37 | | | | | | | | | | | | | |147: | | | | | | | | | Haire Clay Loam, 0 To 2 | Haire | 85 | 0-22 | .43 | 5 | 48 | C | | Percent Slopes | | | | | | | | | | | | 22-27 | .37 | | | | | | | | 27-45 | .24 | | | | | | | | 45-60 | .37 | | | | | | | | | | | | | |148: | | | | | | | | | Haire Clay Loam, 2 To 9 | Haire | 85 | 0-22 | .43 | 5 | 48 | C | | Percent Slopes | | | | | | | | | | | | 22-27 | .37 | | | | | | | | 27-45 | .24 | | | | | | | | 45-60 | .37 | | | | | | | | | | | | | |149: | | | | | | | | | Haire Clay Loam, 9 To 15 | Haire | 85 | 0-22 | .43 | 5 | 48 | C | | Percent Slopes | | | | | | | | | | | | 22-27 | .37 | | | | | | | | 27-45 | .24 | | | | | | | | 45-60 | .37 | | | | | | | | | | | | | |150: | | | | | | | | | Haire Clay Loam, 15 To 30 | Haire | 85 | 0-22 | .43 | 5 | 48 | C | | Percent Slopes | | | | | | | | | | | | 22-27 | .37 | | | | | | | | 27-45 | .24 | | | | | | | | 45-60 | .37 | | | | | | | | | | | | | | | | | | | | | | |151: | | | | | | | | | Hambright-Rock Outcrop | Hambright | 50 | 0-12 | .37 | 1 | 0 | D | | Complex, 2 To 30 Percent | | | | | | | | | Slopes | | | | | | | | | | | | 12-16 | --- | | | | | | | | | | | | | | | Rock Outcrop | 35 | --- | --- | - | --- | --- | | | | | | | | | | |152: | | | | | | | | | Hambright Rock-Outcrop | Hambright | 50 | 0-12 | .37 | 1 | 0 | D | | Complex, 30 To 75 Percent | | | | | | | | | Slopes | | | | | | | | | | | | 12-16 | --- | | | | | | | | | | | | | | | Rock Outcrop | 40 | --- | --- | - | --- | --- | | | | | | | | | | |153: | | | | | | | | | Henneke Gravelly Loam, 5 To | Henneke | 85 | 0-7 | .37 | 1 | 38 | D | | 30 Percent Slopes | | | | | | | | | | | | 7-15 | .37 | | | | | | | | 15-19 | --- | | | | | | | | | | | | | |154: | | | | | | | | | Henneke Gravelly Loam, 30 To | Henneke | 85 | 0-7 | .37 | 1 | 38 | D | | 75 Percent Slopes | | | | | | | | | | | | 7-15 | .37 | | | | | | | | 15-19 | --- | | | | | | | | | | | | | |155: | | | | | | | | | Kidd Loam, 15 To 30 Percent | Kidd | 85 | 0-14 | .37 | 2 | 56 | D | | Slopes | | | | | | | | | | | | 14-18 | --- | | | | | | | | | | | | | |156: | | | | | | | | | Kidd Loam, 30 To 75 Percent | Kidd | 85 | 0-14 | .37 | 2 | 56 | D | | Slopes | | | | | | | | | | | | 14-18 | --- | | | | | | | | | | | | | |157: | | | | | | | | | Lodo-Maymen-Felton | Lodo | 45 | 0-7 | .37 | 2 | 48 | D | | Association, 30 To 75 | | | | | | | | | Percent Slopes | | | | | | | | | | | | 7-11 | --- | | | | | | | | | | | | | | | Maymen | 25 | 0-12 | .24 | 1 | 48 | D | | | | | 12-16 | --- | | | | | | | | | | | | | | | Felton | 20 | 0-10 | .37 | 3 | 38 | C | | | | | 10-33 | .32 | | | | | | | | 33-37 | --- | | | | | | | | | | | | | |158: | | | | | | | | | Los Gatos Loam, 5 To 30 | Los Gatos | 85 | 0-25 | .37 | 2 | 48 | C | | Percent Slopes | | | | | | | | | | | | 25-36 | .37 | | | | | | | | 36-40 | --- | | | | | | | | | | | | | | | | | | | | | | |159: | | | | | | | | | Los Gatos Loam, 30 To 50 | Los Gatos | 85 | 0-25 | .37 | 2 | 48 | C | | Percent Slopes | | | | | | | | | | | | 25-36 | .37 | | | | | | | | 36-40 | --- | | | | | | | | | | | | | |160: | | | | | | | | | Los Gatos Loam, 50 To 75 | Los Gatos | 85 | 0-25 | .37 | 2 | 48 | C | | Percent Slopes | | | | | | | | | | | | 25-36 | .37 | | | | | | | | 36-40 | --- | | | | | | | | | | | | | |161: | | | | | | | | | Maxwell Clay, 2 To 9 Percent | Maxwell | 85 | 0-62 | .28 | 5 | 86 | D | | Slopes | | | | | | | | | | | | | | | | | |162: | | | | | | | | | Maymen-Los Gatos Complex, 50 | Maymen | 60 | 0-12 | .24 | 1 | 0 | D | | To 75 Percent Slopes | | | | | | | | | | | | 12-16 | --- | | | | | | | | | | | | | | | Los Gatos | 25 | 0-25 | .37 | 2 | 48 | C | | | | | 25-36 | .37 | | | | | | | | 36-40 | --- | | | | | | | | | | | | | |163: | | | | | | | | | Maymen-Millsholm-Lodo | Maymen | 30 | 0-12 | .24 | 1 | 48 | D | | Association, 30-75 Percent | | | | | | | | | Slopes | | | | | | | | | | | | 12-16 | --- | | | | | | | | | | | | | | | Millsholm | | 0-12 | .37 | 1 | 48 | D | | | | | 12-16 | --- | | | | | | | | | | | | | | | Lodo | 20 | 0-7 | .37 | 2 | 48 | D | | | | | 7-11 | --- | | | | | | | | | | | | | |164: | | | | | | | | | Millsholm Loam, 15 To 30 | Millsholm | 85 | 0-12 | .37 | 1 | 48 | D | | Percent Slopes | | | | | | | | | | | | 12-16 | --- | | | | | | | | | | | | | |165: | | | | | | | | | Millsholm Loam, 30 To 75 | Millsholm | 85 | 0-12 | .37 | 1 | 48 | D | | Percent Slopes | | | | | | | | | | | | 12-16 | --- | | | | | | | | | | | | | |166: | | | | | | | | | Montara Clay Loam, 5 To 30 | Montara | 85 | 0-12 | .43 | 1 | 48 | D | | Percent Slopes | | | | | | | | | | | | 12-16 | --- | | | | | | | | | | | | | |167: | | | | | | | | | Montara Clay Loam, 30 To 50 | Montara | 85 | 0-12 | .37 | 1 | 48 | D | | Percent Slopes | | | | | | | | | | | | 12-16 | --- | | | | | | | | | | | | | | | | | | | | | | |168: | | | | | | | | | Perkins Gravelly Loam, 2 To 5 | Perkins | 85 | 0-29 | .37 | 5 | 38 | C | | Percent Slopes | | | | | | | | | | | | 29-60 | .37 | | | | | | | | | | | | | |169: | | | | | | | | | Perkins Gravelly Loam, 5 To 9 | Perkins | 85 | 0-29 | .37 | 5 | 38 | C | | Percent Slopes | | | | | | | | | | | | 29-60 | .37 | | | | | | | | | | | | | |170: | | | | | | | | | Pleasanton Loam, 0 To 2 | Pleasanton | 85 | 0-11 | .37 | 5 | 56 | B | | Percent Slopes | | | | | | | | | | | | 11-66 | .37 | | | | | | | | | | | | | |171: | | | | | | | | | Pleasanton Loam, 2 To 5 | Pleasanton | 85 | 0-11 | .37 | 5 | 56 | B | | Percent Slopes | | | | | | | | | | | | 11-66 | .37 | | | | | | | | | | | | | |172: | | | | | | | | | Reyes Silty Clay Loam | Reyes | 85 | 0-14 | .28 | 5 | 86 | D | | | | | 14-60 | .32 | | | | | | | | | | | | | |173: | | | | | | | | | Reyes Silty Clay Loam, Salt | Reyes | 85 | 0-14 | .28 | 5 | 86 | D | | Ponds | | | | | | | | | | | | 14-60 | .28 | | | | | | | | | | | | | |174: | | | | | | | | | Riverwash | Riverwash | 100 | --- | --- | - | --- | --- | | | | | | | | | | |175: | | | | | | | | | Rock Outcrop | Rock Outcrop | 100 | --- | --- | - | --- | --- | | | | | | | | | | |176: | | | | | | | | | Rock Outcrop-Hambright | Rock Outcrop | 60 | --- | --- | - | --- | --- | | Complex, 50 To 75 Percent | | | | | | | | | Slopes | | | | | | | | | | | | | | | | | | | Hambright | 30 | 0-12 | .37 | 1 | 0 | D | | | | | 12-16 | --- | | | | | | | | | | | | | |177: | | | | | | | | | Rock Outcrop-Kidd Complex, 50 | Rock Outcrop | 70 | --- | --- | - | --- | --- | | To 75 Percent Slopes | | | | | | | | | | | | | | | | | | | Kidd | 25 | 0-14 | .37 | 2 | 0 | D | | | | | 14-18 | --- | | | | | | | | | | | | | |178: | | | | | | | | | Sobrante Loam, 5 To 30 | Sobrante | 85 | 0-6 | .49 | 2 | 48 | C | | Percent Slopes | | | | | | | | | | | | 6-30 | .37 | | | | | | | | 30-34 | --- | | | | | | | | | | | | | | | | | | | | | | |179: | | | | | | | | | Sobrante Loam, 30 To 50 | Sobrante | 85 | 0-6 | .49 | 2 | 48 | C | | Percent Slopes | | | | | | | | | | | | 6-30 | .37 | | | | | | | | 30-34 | --- | | | | | | | | | | | | | |180: | | | | | | | | | Tehama Silt Loam, 0 To 5 | Tehama | 85 | 0-12 | .37 | 5 | 56 | C | | Percent Slopes | | | | | | | | | | | | 12-60 | .37 | | | | | | | | | | | | | |181: | | | | | | | | | Yolo Loam, 0 To 2 Percent | Yolo | 85 | 0-24 | .37 | 5 | 48 | B | | Slopes | | | | | | | | | | | | 24-60 | .37 | | | | | | | | | | | | | |182: | | | | | | | | | Yolo Loam, 2 To 5 Percent | Yolo | 85 | 0-24 | .37 | 5 | 48 | B | | Slopes | | | | | | | | | | | | 24-60 | .37 | | | | | | | | | | | | | |185: | | | | | | | | | Pits, Quarry | Pits, Quarry | 100 | --- | --- | - | --- | --- | | | | | | | | | | |________________________________|____________________|____________|____________|_________|_______|__________|______| 1/ The Soil Erodibility Factor Kf is used in the Revised Universal Soil Loss Equation (RUSLE) and indicates the susceptibility of the fine-earth fraction of the soil to sheet and rill erosion by rainfall. Rocks and rock fragments in the soil profile are not considered. Values for Kf range from .10 to .64. The higher the value, the more susceptible the soil is to sheet and rill erosion by rainfall. 2/ The Soil Loss Tolerance (T)value is an estimate of the maximum average annual rate of soil erosion by wind or water that can occur without affecting crop productivity over a sustained period. Values of T range from 1 to 5 tons/acre/year and are based on depth of soil to bedrock and the type of bedrock. 3/ The Wind Erodibility Index I value is used in the Wind Erosion Equation (WEQ) and is based on soil texture and the relationship of dry soil aggregates greater than .84 mm to potential erosion rates of 0 to 310 tons/acre/year from a wide, bare field. This value applies only to the surface layer. Erosion factors are shown in this table as the K factor (Kf) and the T factor. Erosion factor K indicates the susceptibility of a soil to sheet and rill erosion by water. Factor K is one of six factors used in the Universal Soil Loss Equation (USLE) and the Revised Universal Soil Loss Equation (RUSLE) to predict the average annual rate of soil loss by sheet and rill erosion in tons per acre per year. The estimates are based primarily on percentage of silt, sand, and organic matter and on soil structure and permeability. Values of K range from 0.02 to 0.69. Other factors being equal, the higher the value, the more susceptible the soil is to sheet and rill erosion by water. Erosion factor Kf indicates the erodibility of the fine-earth fraction, or the material less than 2 millimeters in size. Erosion factor T is an estimate of the maximum average annual rate of soil erosion by wind or water that can occur without affecting crop productivity over a sustained period. The rate is in tons per acre per year. Wind erodibility groups are made up of soils that have similar properties affecting their susceptibility to wind erosion in cultivated areas. The soils assigned to group 1 are the most susceptible to wind erosion, and those assigned to group 8 are the least susceptible. The groups are as follows: 1  Coarse sands, sands, fine sands, and very fine sands. 2  Loamy coarse sands, loamy sands, loamy fine sands, loamy very fine sands, ash material, and sapric soil material. 3  Coarse sandy loams, sandy loams, fine sandy loams, and very fine sandy loams. 4L Calcareous loams, silt loams, clay loams, and silty clay loams. 4  Clays, silty clays, noncalcareous clay loams, and silty clay loams that are more than 35 percent clay. 5  Noncalcareous loams and silt loams that are less than 20 percent clay and sandy clay loams, sandy clays, and hemic soil material. 6  Noncalcareous loams and silt loams that are more than 20 percent clay and noncalcareous clay loams that are less than 35 percent clay. 7  Silts, noncalcareous silty clay loams that are less than 35 percent clay, and fibric soil material. 8  Soils that are not subject to wind erosion because of coarse fragments on the surface or because of surface wetness. Wind erodibility index is a numerical value indicating the susceptibility of soil to wind erosion, or the tons per acre per year that can be expected to be lost to wind erosion. There is a close correlation between wind erosion and the texture of the surface layer, the size and durability of surface clods, rock fragments, organic matter, and a calcareous reaction. Soil moisture and frozen soil layers also influence wind erosion.