Loading...
HomeMy WebLinkAboutNRCSSoilsData23Pgs_051620219 Custom Soil Resource Report Soil Map 5059080505911050591405059170505920050592305059260505929050590805059110505914050591705059200505923050592605059290494520 494550 494580 494610 494640 494670 494700 494730 494760 494790 494820 494850 494520 494550 494580 494610 494640 494670 494700 494730 494760 494790 494820 494850 45° 41' 13'' N 111° 4' 13'' W45° 41' 13'' N111° 3' 57'' W45° 41' 6'' N 111° 4' 13'' W45° 41' 6'' N 111° 3' 57'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 12N WGS84 0 50 100 200 300 Feet 0 20 40 80 120 Meters Map Scale: 1:1,610 if printed on A landscape (11" x 8.5") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Gallatin County Area, Montana Survey Area Data: Version 24, Jun 4, 2020 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Aug 3, 2009—Sep 1, 2016 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Custom Soil Resource Report 10 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 50B Blackdog silt loam, 0 to 4 percent slopes 1.6 12.5% 457A Turner loam, moderately wet, 0 to 2 percent slopes 8.1 61.7% 510B Meadowcreek loam, 0 to 4 percent slopes 2.8 21.5% UL Urban land 0.6 4.4% Totals for Area of Interest 13.2 100.0% Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate Custom Soil Resource Report 11 pure taxonomic classes but rather to separate the landscape into landforms or landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, onsite investigation is needed to define and locate the soils and miscellaneous areas. An identifying symbol precedes the map unit name in the map unit descriptions. Each description includes general facts about the unit and gives important soil properties and qualities. Soils that have profiles that are almost alike make up a soil series. Except for differences in texture of the surface layer, all the soils of a series have major horizons that are similar in composition, thickness, and arrangement. Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity, degree of erosion, and other characteristics that affect their use. On the basis of such differences, a soil series is divided into soil phases. Most of the areas shown on the detailed soil maps are phases of soil series. The name of a soil phase commonly indicates a feature that affects use or management. For example, Alpha silt loam, 0 to 2 percent slopes, is a phase of the Alpha series. Some map units are made up of two or more major soils or miscellaneous areas. These map units are complexes, associations, or undifferentiated groups. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps. The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. Alpha-Beta complex, 0 to 6 percent slopes, is an example. An association is made up of two or more geographically associated soils or miscellaneous areas that are shown as one unit on the maps. Because of present or anticipated uses of the map units in the survey area, it was not considered practical or necessary to map the soils or miscellaneous areas separately. The pattern and relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha-Beta association, 0 to 2 percent slopes, is an example. An undifferentiated group is made up of two or more soils or miscellaneous areas that could be mapped individually but are mapped as one unit because similar interpretations can be made for use and management. The pattern and proportion of the soils or miscellaneous areas in a mapped area are not uniform. An area can be made up of only one of the major soils or miscellaneous areas, or it can be made up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example. Some surveys include miscellaneous areas. Such areas have little or no soil material and support little or no vegetation. Rock outcrop is an example. Custom Soil Resource Report 12 Gallatin County Area, Montana 50B—Blackdog silt loam, 0 to 4 percent slopes Map Unit Setting National map unit symbol: 56vq Elevation: 4,350 to 5,500 feet Mean annual precipitation: 15 to 19 inches Mean annual air temperature: 37 to 43 degrees F Frost-free period: 90 to 110 days Farmland classification: All areas are prime farmland Map Unit Composition Blackdog and similar soils:90 percent Minor components:10 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Blackdog Setting Landform:Stream terraces Down-slope shape:Linear Across-slope shape:Linear Parent material:Calcareous loess Typical profile A - 0 to 10 inches: silt loam Bt - 10 to 19 inches: silty clay loam Bk - 19 to 60 inches: silt loam Properties and qualities Slope:0 to 4 percent Depth to restrictive feature:More than 80 inches Drainage class:Well drained Capacity of the most limiting layer to transmit water (Ksat):Moderately high (0.20 to 0.57 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:30 percent Available water capacity:High (about 10.9 inches) Interpretive groups Land capability classification (irrigated): 3e Land capability classification (nonirrigated): 3e Hydrologic Soil Group: C Ecological site: R044BB032MT - Loamy (Lo) LRU 44B-B Hydric soil rating: No Minor Components Meagher Percent of map unit:4 percent Landform:Alluvial fans, stream terraces Down-slope shape:Linear Across-slope shape:Linear Custom Soil Resource Report 13 Ecological site:R044XS355MT - Silty (Si) 15-19" p.z. Hydric soil rating: No Quagle Percent of map unit:3 percent Landform:Stream terraces Down-slope shape:Linear Across-slope shape:Linear Ecological site:R044XS357MT - Limy (Ly) 15-19" p.z. Hydric soil rating: No Bowery Percent of map unit:3 percent Landform:Alluvial fans, stream terraces Down-slope shape:Linear Across-slope shape:Linear Ecological site:R044XS355MT - Silty (Si) 15-19" p.z. Hydric soil rating: No 457A—Turner loam, moderately wet, 0 to 2 percent slopes Map Unit Setting National map unit symbol: 56tb Elevation: 4,300 to 5,200 feet Mean annual precipitation: 15 to 19 inches Mean annual air temperature: 39 to 45 degrees F Frost-free period: 90 to 110 days Farmland classification: Prime farmland if irrigated Map Unit Composition Turner and similar soils:85 percent Minor components:15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Turner Setting Landform:Stream terraces Down-slope shape:Linear Across-slope shape:Linear Parent material:Alluvium Typical profile A - 0 to 6 inches: loam Bt - 6 to 12 inches: clay loam Bk - 12 to 26 inches: clay loam 2C - 26 to 60 inches: very gravelly loamy sand Properties and qualities Slope:0 to 2 percent Depth to restrictive feature:More than 80 inches Custom Soil Resource Report 14 Drainage class:Well drained Capacity of the most limiting layer to transmit water (Ksat):Moderately high to high (0.57 to 1.98 in/hr) Depth to water table:About 48 to 96 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:15 percent Maximum salinity:Nonsaline to very slightly saline (0.0 to 2.0 mmhos/cm) Available water capacity:Low (about 5.4 inches) Interpretive groups Land capability classification (irrigated): 3e Land capability classification (nonirrigated): 3e Hydrologic Soil Group: B Ecological site: R044BB032MT - Loamy (Lo) LRU 44B-B Hydric soil rating: No Minor Components Meadowcreek Percent of map unit:5 percent Landform:Stream terraces Down-slope shape:Linear Across-slope shape:Linear Ecological site:R044XS359MT - Subirrigated (Sb) 15-19" p.z. Hydric soil rating: No Beaverton Percent of map unit:5 percent Landform:Alluvial fans, stream terraces Down-slope shape:Linear Across-slope shape:Linear Ecological site:R044XS354MT - Shallow to Gravel (SwGr) 15-19" p.z. Hydric soil rating: No Turner Percent of map unit:5 percent Landform:Stream terraces Down-slope shape:Linear Across-slope shape:Linear Ecological site:R044XS355MT - Silty (Si) 15-19" p.z. Hydric soil rating: No 510B—Meadowcreek loam, 0 to 4 percent slopes Map Unit Setting National map unit symbol: 56vt Elevation: 4,200 to 5,950 feet Mean annual precipitation: 12 to 18 inches Mean annual air temperature: 39 to 45 degrees F Frost-free period: 90 to 110 days Custom Soil Resource Report 15 Farmland classification: Prime farmland if irrigated Map Unit Composition Meadowcreek and similar soils:85 percent Minor components:15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Meadowcreek Setting Landform:Stream terraces Down-slope shape:Linear Across-slope shape:Linear Parent material:Alluvium Typical profile A - 0 to 11 inches: loam Bg - 11 to 25 inches: silt loam 2C - 25 to 60 inches: very gravelly sand Properties and qualities Slope:0 to 4 percent Depth to restrictive feature:More than 80 inches Drainage class:Somewhat poorly drained Capacity of the most limiting layer to transmit water (Ksat):Moderately high to high (0.57 to 1.98 in/hr) Depth to water table:About 24 to 42 inches Frequency of flooding:None Frequency of ponding:None Maximum salinity:Nonsaline to slightly saline (0.0 to 4.0 mmhos/cm) Available water capacity:Low (about 5.1 inches) Interpretive groups Land capability classification (irrigated): 2e Land capability classification (nonirrigated): 3e Hydrologic Soil Group: C Ecological site: R044BY150MT - Subirrigated (Sb) LRU 44B-Y Hydric soil rating: No Minor Components Blossberg Percent of map unit:10 percent Landform:Terraces Down-slope shape:Linear Across-slope shape:Linear Ecological site:R044XS365MT - Wet Meadow (WM) 15-19" p.z. Hydric soil rating: Yes Beaverton Percent of map unit:5 percent Landform:Alluvial fans, stream terraces Down-slope shape:Linear Across-slope shape:Linear Ecological site:R044XS354MT - Shallow to Gravel (SwGr) 15-19" p.z. Hydric soil rating: No Custom Soil Resource Report 16 UL—Urban land Map Unit Composition Urban land:100 percent Estimates are based on observations, descriptions, and transects of the mapunit. Custom Soil Resource Report 17 Soil Information for All Uses Soil Reports The Soil Reports section includes various formatted tabular and narrative reports (tables) containing data for each selected soil map unit and each component of each unit. No aggregation of data has occurred as is done in reports in the Soil Properties and Qualities and Suitabilities and Limitations sections. The reports contain soil interpretive information as well as basic soil properties and qualities. A description of each report (table) is included. Building Site Development This folder contains a collection of tabular reports that present soil interpretations related to building site development. The reports (tables) include all selected map units and components for each map unit, limiting features and interpretive ratings. Building site development interpretations are designed to be used as tools for evaluating soil suitability and identifying soil limitations for various construction purposes. As part of the interpretation process, the rating applies to each soil in its described condition and does not consider present land use. Example interpretations can include corrosion of concrete and steel, shallow excavations, dwellings with and without basements, small commercial buildings, local roads and streets, and lawns and landscaping. Roads and Streets, Shallow Excavations, and Lawns and Landscaping Soil properties influence the development of building sites, including the selection of the site, the design of the structure, construction, performance after construction, and maintenance. This table shows the degree and kind of soil limitations that affect local roads and streets, shallow excavations, and lawns and landscaping. The ratings in the table are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect building site development. Not limited indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. Somewhat limited indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and 18 moderate maintenance can be expected. Very limited indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected. Numerical ratings in the table indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00). Local roads and streets have an all-weather surface and carry automobile and light truck traffic all year. They have a subgrade of cut or fill soil material; a base of gravel, crushed rock, or soil material stabilized by lime or cement; and a surface of flexible material (asphalt), rigid material (concrete), or gravel with a binder. The ratings are based on the soil properties that affect the ease of excavation and grading and the traffic-supporting capacity. The properties that affect the ease of excavation and grading are depth to bedrock or a cemented pan, hardness of bedrock or a cemented pan, depth to a water table, ponding, flooding, the amount of large stones, and slope. The properties that affect the traffic-supporting capacity are soil strength (as inferred from the AASHTO group index number), subsidence, linear extensibility (shrink-swell potential), the potential for frost action, depth to a water table, and ponding. Shallow excavations are trenches or holes dug to a maximum depth of 5 or 6 feet for graves, utility lines, open ditches, or other purposes. The ratings are based on the soil properties that influence the ease of digging and the resistance to sloughing. Depth to bedrock or a cemented pan, hardness of bedrock or a cemented pan, the amount of large stones, and dense layers influence the ease of digging, filling, and compacting. Depth to the seasonal high water table, flooding, and ponding may restrict the period when excavations can be made. Slope influences the ease of using machinery. Soil texture, depth to the water table, and linear extensibility (shrink-swell potential) influence the resistance to sloughing. Lawns and landscaping require soils on which turf and ornamental trees and shrubs can be established and maintained. Irrigation is not considered in the ratings. The ratings are based on the soil properties that affect plant growth and trafficability after vegetation is established. The properties that affect plant growth are reaction; depth to a water table; ponding; depth to bedrock or a cemented pan; the available water capacity in the upper 40 inches; the content of salts, sodium, or calcium carbonate; and sulfidic materials. The properties that affect trafficability are flooding, depth to a water table, ponding, slope, stoniness, and the amount of sand, clay, or organic matter in the surface layer. Information in this table is intended for land use planning, for evaluating land use alternatives, and for planning site investigations prior to design and construction. The information, however, has limitations. For example, estimates and other data generally apply only to that part of the soil between the surface and a depth of 5 to 7 feet. Because of the map scale, small areas of different soils may be included within the mapped areas of a specific soil. The information is not site specific and does not eliminate the need for onsite investigation of the soils or for testing and analysis by personnel experienced in the design and construction of engineering works. Government ordinances and regulations that restrict certain land uses or impose specific design criteria were not considered in preparing the information in this table. Custom Soil Resource Report 19 Local ordinances and regulations should be considered in planning, in site selection, and in design. Report—Roads and Streets, Shallow Excavations, and Lawns and Landscaping [Onsite investigation may be needed to validate the interpretations in this table and to confirm the identity of the soil on a given site. The numbers in the value columns range from 0.01 to 1.00. The larger the value, the greater the potential limitation. The table shows only the top five limitations for any given soil. The soil may have additional limitations] Roads and Streets, Shallow Excavations, and Lawns and Landscaping–Gallatin County Area, Montana Map symbol and soil name Pct. of map unit Lawns and landscaping Local roads and streets Shallow excavations Rating class and limiting features Value Rating class and limiting features Value Rating class and limiting features Value 50B—Blackdog silt loam, 0 to 4 percent slopes Blackdog 90 Somewhat limited Somewhat limited Somewhat limited Dusty 0.07 Low strength 0.93 Dusty 0.07 Frost action 0.50 Unstable excavation walls 0.01 457A—Turner loam, moderately wet, 0 to 2 percent slopes Turner 85 Somewhat limited Somewhat limited Somewhat limited Dusty 0.09 Frost action 0.50 Dusty 0.09 Shrink-swell 0.01 Unstable excavation walls 0.01 510B—Meadowcreek loam, 0 to 4 percent slopes Meadowcreek 85 Somewhat limited Very limited Somewhat limited Dusty 0.14 Frost action 1.00 Depth to saturated zone 0.99 Dusty 0.14 Unstable excavation walls 0.01 UL—Urban land Urban land 100 Not rated Not rated Not rated Dwellings and Small Commercial Buildings Soil properties influence the development of building sites, including the selection of the site, the design of the structure, construction, performance after construction, and maintenance. This table shows the degree and kind of soil limitations that affect dwellings and small commercial buildings. Custom Soil Resource Report 20 The ratings in the table are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect building site development. Not limited indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. Somewhat limited indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. Very limited indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. Poor performance and high maintenance can be expected. Numerical ratings in the table indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00). Dwellings are single-family houses of three stories or less. For dwellings without basements, the foundation is assumed to consist of spread footings of reinforced concrete built on undisturbed soil at a depth of 2 feet or at the depth of maximum frost penetration, whichever is deeper. For dwellings with basements, the foundation is assumed to consist of spread footings of reinforced concrete built on undisturbed soil at a depth of about 7 feet. The ratings for dwellings are based on the soil properties that affect the capacity of the soil to support a load without movement and on the properties that affect excavation and construction costs. The properties that affect the load-supporting capacity include depth to a water table, ponding, flooding, subsidence, linear extensibility (shrink-swell potential), and compressibility. Compressibility is inferred from the Unified classification. The properties that affect the ease and amount of excavation include depth to a water table, ponding, flooding, slope, depth to bedrock or a cemented pan, hardness of bedrock or a cemented pan, and the amount and size of rock fragments. Small commercial buildings are structures that are less than three stories high and do not have basements. The foundation is assumed to consist of spread footings of reinforced concrete built on undisturbed soil at a depth of 2 feet or at the depth of maximum frost penetration, whichever is deeper. The ratings are based on the soil properties that affect the capacity of the soil to support a load without movement and on the properties that affect excavation and construction costs. The properties that affect the load-supporting capacity include depth to a water table, ponding, flooding, subsidence, linear extensibility (shrink-swell potential), and compressibility (which is inferred from the Unified classification). The properties that affect the ease and amount of excavation include flooding, depth to a water table, ponding, slope, depth to bedrock or a cemented pan, hardness of bedrock or a cemented pan, and the amount and size of rock fragments. Information in this table is intended for land use planning, for evaluating land use alternatives, and for planning site investigations prior to design and construction. The information, however, has limitations. For example, estimates and other data generally apply only to that part of the soil between the surface and a depth of 5 to 7 feet. Because of the map scale, small areas of different soils may be included within the mapped areas of a specific soil. The information is not site specific and does not eliminate the need for onsite investigation of the soils or for testing and analysis by personnel experienced in the design and construction of engineering works. Custom Soil Resource Report 21 Government ordinances and regulations that restrict certain land uses or impose specific design criteria were not considered in preparing the information in this table. Local ordinances and regulations should be considered in planning, in site selection, and in design. Report—Dwellings and Small Commercial Buildings [Onsite investigation may be needed to validate the interpretations in this table and to confirm the identity of the soil on a given site. The numbers in the value columns range from 0.01 to 1.00. The larger the value, the greater the potential limitation. The table shows only the top five limitations for any given soil. The soil may have additional limitations] Dwellings and Small Commercial Buildings–Gallatin County Area, Montana Map symbol and soil name Pct. of map unit Dwellings without basements Dwellings with basements Small commercial buildings Rating class and limiting features Value Rating class and limiting features Value Rating class and limiting features Value 50B—Blackdog silt loam, 0 to 4 percent slopes Blackdog 90 Not limited Not limited Not limited 457A—Turner loam, moderately wet, 0 to 2 percent slopes Turner 85 Somewhat limited Not limited Somewhat limited Shrink-swell 0.01 Shrink-swell 0.01 510B—Meadowcreek loam, 0 to 4 percent slopes Meadowcreek 85 Not limited Somewhat limited Not limited Depth to saturated zone 0.99 UL—Urban land Urban land 100 Not rated Not rated Not rated Soil Physical Properties This folder contains a collection of tabular reports that present soil physical properties. The reports (tables) include all selected map units and components for each map unit. Soil physical properties are measured or inferred from direct observations in the field or laboratory. Examples of soil physical properties include percent clay, organic matter, saturated hydraulic conductivity, available water capacity, and bulk density. Custom Soil Resource Report 22 Physical Soil Properties This table shows estimates of some physical characteristics and features that affect soil behavior. These estimates are given for the layers of each soil in the survey area. The estimates are based on field observations and on test data for these and similar soils. Depth to the upper and lower boundaries of each layer is indicated. Particle size is the effective diameter of a soil particle as measured by sedimentation, sieving, or micrometric methods. Particle sizes are expressed as classes with specific effective diameter class limits. The broad classes are sand, silt, and clay, ranging from the larger to the smaller. Sand as a soil separate consists of mineral soil particles that are 0.05 millimeter to 2 millimeters in diameter. In this table, the estimated sand content of each soil layer is given as a percentage, by weight, of the soil material that is less than 2 millimeters in diameter. Silt as a soil separate consists of mineral soil particles that are 0.002 to 0.05 millimeter in diameter. In this table, the estimated silt content of each soil layer is given as a percentage, by weight, of the soil material that is less than 2 millimeters in diameter. Clay as a soil separate consists of mineral soil particles that are less than 0.002 millimeter in diameter. In this table, the estimated clay content of each soil layer is given as a percentage, by weight, of the soil material that is less than 2 millimeters in diameter. The content of sand, silt, and clay affects the physical behavior of a soil. Particle size is important for engineering and agronomic interpretations, for determination of soil hydrologic qualities, and for soil classification. The amount and kind of clay affect the fertility and physical condition of the soil and the ability of the soil to adsorb cations and to retain moisture. They influence shrink- swell potential, saturated hydraulic conductivity (Ksat), plasticity, the ease of soil dispersion, and other soil properties. The amount and kind of clay in a soil also affect tillage and earthmoving operations. Moist bulk density is the weight of soil (ovendry) per unit volume. Volume is measured when the soil is at field moisture capacity, that is, the moisture content at 1/3- or 1/10-bar (33kPa or 10kPa) moisture tension. Weight is determined after the soil is dried at 105 degrees C. In the table, the estimated moist bulk density of each soil horizon is expressed in grams per cubic centimeter of soil material that is less than 2 millimeters in diameter. Bulk density data are used to compute linear extensibility, shrink-swell potential, available water capacity, total pore space, and other soil properties. The moist bulk density of a soil indicates the pore space available for water and roots. Depending on soil texture, a bulk density of more than 1.4 can restrict water storage and root penetration. Moist bulk density is influenced by texture, kind of clay, content of organic matter, and soil structure. Saturated hydraulic conductivity (Ksat) refers to the ease with which pores in a saturated soil transmit water. The estimates in the table are expressed in terms of micrometers per second. They are based on soil characteristics observed in the field, particularly structure, porosity, and texture. Saturated hydraulic conductivity (Ksat) is considered in the design of soil drainage systems and septic tank absorption fields. Custom Soil Resource Report 23 Available water capacity refers to the quantity of water that the soil is capable of storing for use by plants. The capacity for water storage is given in inches of water per inch of soil for each soil layer. The capacity varies, depending on soil properties that affect retention of water. The most important properties are the content of organic matter, soil texture, bulk density, and soil structure. Available water capacity is an important factor in the choice of plants or crops to be grown and in the design and management of irrigation systems. Available water capacity is not an estimate of the quantity of water actually available to plants at any given time. Linear extensibility refers to the change in length of an unconfined clod as moisture content is decreased from a moist to a dry state. It is an expression of the volume change between the water content of the clod at 1/3- or 1/10-bar tension (33kPa or 10kPa tension) and oven dryness. The volume change is reported in the table as percent change for the whole soil. The amount and type of clay minerals in the soil influence volume change. Linear extensibility is used to determine the shrink-swell potential of soils. The shrink-swell potential is low if the soil has a linear extensibility of less than 3 percent; moderate if 3 to 6 percent; high if 6 to 9 percent; and very high if more than 9 percent. If the linear extensibility is more than 3, shrinking and swelling can cause damage to buildings, roads, and other structures and to plant roots. Special design commonly is needed. Organic matter is the plant and animal residue in the soil at various stages of decomposition. In this table, the estimated content of organic matter is expressed as a percentage, by weight, of the soil material that is less than 2 millimeters in diameter. The content of organic matter in a soil can be maintained by returning crop residue to the soil. Organic matter has a positive effect on available water capacity, water infiltration, soil organism activity, and tilth. It is a source of nitrogen and other nutrients for crops and soil organisms. Erosion factors are shown in the table as the K factor (Kw and 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 Ksat. 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 Kw indicates the erodibility of the whole soil. The estimates are modified by the presence of rock fragments. 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 and/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 described in the "National Soil Survey Handbook." Custom Soil Resource Report 24 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. Reference: United States Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 430-VI. (http://soils.usda.gov) Custom Soil Resource Report 25 Three values are provided to identify the expected Low (L), Representative Value (R), and High (H). Physical Soil Properties–Gallatin County Area, Montana Map symbol and soil name Depth Sand Silt Clay Moist bulk density Saturated hydraulic conductivity Available water capacity Linear extensibility Organic matter Erosion factors Wind erodibility group Wind erodibility indexKwKfT In Pct Pct Pct g/cc micro m/sec In/In Pct Pct 50B—Blackdog silt loam, 0 to 4 percent slopes Blackdog 0-10 - 9--67-20-24- 27 1.10-1.20- 1.30 4.00-9.00-14.00 0.18-0.19-0.2 0 0.0- 1.5- 2.9 2.0- 3.0- 4.0 .37 .37 5 6 48 10-19 - 7--62-27-31- 35 1.20-1.30- 1.40 1.40-2.70-4.00 0.16-0.18-0.2 0 3.0- 4.5- 5.9 1.0- 2.0- 3.0 .37 .37 19-60 -11--69-15-20- 25 1.20-1.30- 1.40 4.00-9.00-14.00 0.16-0.18-0.2 0 0.0- 1.5- 2.9 0.5- 0.8- 1.0 .49 .49 457A—Turner loam, moderately wet, 0 to 2 percent slopes Turner 0-6 -42--37-15-21- 27 1.10-1.20- 1.30 4.00-9.00-14.00 0.15-0.17-0.1 9 0.0- 1.5- 2.9 2.0- 3.0- 4.0 .24 .24 3 6 48 6-12 -34--37-25-30- 35 1.30-1.40- 1.50 4.00-9.00-14.00 0.12-0.15-0.1 8 3.0- 4.5- 5.9 0.5- 1.3- 2.0 .28 .28 12-26 -34--38-18-28- 35 1.35-1.43- 1.50 4.00-9.00-14.00 0.12-0.15-0.1 8 3.0- 4.5- 5.9 0.0- 0.3- 0.5 .32 .32 26-60 -81--17-0- 3- 5 1.35-1.43- 1.50 42.00-92.00-14 1.00 0.01-0.04-0.0 6 0.0- 1.5- 2.9 0.0- 0.3- 0.5 .05 .15 Custom Soil Resource Report 26 Physical Soil Properties–Gallatin County Area, Montana Map symbol and soil name Depth Sand Silt Clay Moist bulk density Saturated hydraulic conductivity Available water capacity Linear extensibility Organic matter Erosion factors Wind erodibility group Wind erodibility indexKwKfT In Pct Pct Pct g/cc micro m/sec In/In Pct Pct 510B— Meadowcreek loam, 0 to 4 percent slopes Meadowcreek 0-11 -41--37-18-22- 25 1.20-1.30- 1.40 4.00-9.00-14.00 0.18-0.19-0.2 0 0.0- 1.5- 2.9 2.0- 3.5- 5.0 .24 .24 3 6 48 11-25 -20--54-18-26- 27 1.20-1.30- 1.40 4.00-9.00-14.00 0.13-0.14-0.1 5 0.0- 1.5- 2.9 1.0- 2.0- 3.0 .37 .37 25-60 -96-- 2-0- 3- 5 1.20-1.35- 1.50 141.00-141.00- 141.00 0.02-0.03-0.0 3 0.0- 1.5- 2.9 0.0- 0.3- 0.5 .02 .02 UL—Urban land Urban land ————————— Custom Soil Resource Report 27 Water Features This folder contains tabular reports that present soil hydrology information. The reports (tables) include all selected map units and components for each map unit. Water Features include ponding frequency, flooding frequency, and depth to water table. Hydrologic Soil Group and Surface Runoff This table gives estimates of various soil water features. The estimates are used in land use planning that involves engineering considerations. Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long-duration storms. The four hydrologic soil groups are: Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential) when thoroughly wet. These consist chiefly of clays that have a high shrink-swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the second is for undrained areas. Surface runoff refers to the loss of water from an area by flow over the land surface. Surface runoff classes are based on slope, climate, and vegetative cover. The concept indicates relative runoff for very specific conditions. It is assumed that the surface of the soil is bare and that the retention of surface water resulting from irregularities in the ground surface is minimal. The classes are negligible, very low, low, medium, high, and very high. Report—Hydrologic Soil Group and Surface Runoff Absence of an entry indicates that the data were not estimated. The dash indicates no documented presence. Custom Soil Resource Report 28 Hydrologic Soil Group and Surface Runoff–Gallatin County Area, Montana Map symbol and soil name Pct. of map unit Surface Runoff Hydrologic Soil Group 50B—Blackdog silt loam, 0 to 4 percent slopes Blackdog 90 —C 457A—Turner loam, moderately wet, 0 to 2 percent slopes Turner 85 —B 510B—Meadowcreek loam, 0 to 4 percent slopes Meadowcreek 85 —C UL—Urban land Urban land 100 —— Custom Soil Resource Report 29 References American Association of State Highway and Transportation Officials (AASHTO). 2004. Standard specifications for transportation materials and methods of sampling and testing. 24th edition. American Society for Testing and Materials (ASTM). 2005. Standard classification of soils for engineering purposes. ASTM Standard D2487-00. Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deep-water habitats of the United States. U.S. Fish and Wildlife Service FWS/OBS-79/31. Federal Register. July 13, 1994. Changes in hydric soils of the United States. Federal Register. September 18, 2002. Hydric soils of the United States. Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric soils in the United States. National Research Council. 1995. Wetlands: Characteristics and boundaries. Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S. Department of Agriculture Handbook 18. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/national/soils/?cid=nrcs142p2_054262 Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service, U.S. Department of Agriculture Handbook 436. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053577 Soil Survey Staff. 2010. Keys to soil taxonomy. 11th edition. U.S. Department of Agriculture, Natural Resources Conservation Service. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053580 Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and Delaware Department of Natural Resources and Environmental Control, Wetlands Section. United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual. Waterways Experiment Station Technical Report Y-87-1. United States Department of Agriculture, Natural Resources Conservation Service. National forestry manual. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ home/?cid=nrcs142p2_053374 United States Department of Agriculture, Natural Resources Conservation Service. National range and pasture handbook. http://www.nrcs.usda.gov/wps/portal/nrcs/ detail/national/landuse/rangepasture/?cid=stelprdb1043084 30 United States Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 430-VI. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/soils/scientists/?cid=nrcs142p2_054242 United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/? cid=nrcs142p2_053624 United States Department of Agriculture, Soil Conservation Service. 1961. Land capability classification. U.S. Department of Agriculture Handbook 210. http:// www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052290.pdf Custom Soil Resource Report 31