APPENDIX D: NRCS SOIL REPORT · 2020-02-20 · Custom Soil Resource Report for Travis County, Natural Texas Resources Conservation Service January 18, 2017. ... color, national origin,

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APPENDIX D: NRCS SOIL REPORT

United StatesDepartment ofAgriculture

A product of the NationalCooperative Soil Survey,a joint effort of the UnitedStates Department ofAgriculture and otherFederal agencies, Stateagencies including theAgricultural ExperimentStations, and localparticipants

Custom Soil ResourceReport for

Travis County,Texas

NaturalResourcesConservationService

January 18, 2017

PrefaceSoil surveys contain information that affects land use planning in survey areas.They highlight soil limitations that affect various land uses and provide informationabout the properties of the soils in the survey areas. Soil surveys are designed formany different users, including farmers, ranchers, foresters, agronomists, urbanplanners, community officials, engineers, developers, builders, and home buyers.Also, conservationists, teachers, students, and specialists in recreation, wastedisposal, and pollution control can use the surveys to help them understand,protect, or enhance the environment.

Various land use regulations of Federal, State, and local governments may imposespecial restrictions on land use or land treatment. Soil surveys identify soilproperties that are used in making various land use or land treatment decisions.The information is intended to help the land users identify and reduce the effects ofsoil limitations on various land uses. The landowner or user is responsible foridentifying and complying with existing laws and regulations.

Although soil survey information can be used for general farm, local, and wider areaplanning, onsite investigation is needed to supplement this information in somecases. Examples include soil quality assessments (http://www.nrcs.usda.gov/wps/portal/nrcs/main/soils/health/) and certain conservation and engineeringapplications. For more detailed information, contact your local USDA Service Center(https://offices.sc.egov.usda.gov/locator/app?agency=nrcs) or your NRCS State SoilScientist (http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/contactus/?cid=nrcs142p2_053951).

Great differences in soil properties can occur within short distances. Some soils areseasonally wet or subject to flooding. Some are too unstable to be used as afoundation for buildings or roads. Clayey or wet soils are poorly suited to use asseptic tank absorption fields. A high water table makes a soil poorly suited tobasements or underground installations.

The National Cooperative Soil Survey is a joint effort of the United StatesDepartment of Agriculture and other Federal agencies, State agencies including theAgricultural Experiment Stations, and local agencies. The Natural ResourcesConservation Service (NRCS) has leadership for the Federal part of the NationalCooperative Soil Survey.

Information about soils is updated periodically. Updated information is availablethrough the NRCS Web Soil Survey, the site for official soil survey information.

The U.S. Department of Agriculture (USDA) prohibits discrimination in all itsprograms and activities on the basis of race, color, national origin, age, disability,and where applicable, sex, marital status, familial status, parental status, religion,sexual orientation, genetic information, political beliefs, reprisal, or because all or apart of an individual's income is derived from any public assistance program. (Notall prohibited bases apply to all programs.) Persons with disabilities who require

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http://www.nrcs.usda.gov/wps/portal/nrcs/main/soils/health/

http://www.nrcs.usda.gov/wps/portal/nrcs/main/soils/health/

https://offices.sc.egov.usda.gov/locator/app?agency=nrcs

http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/contactus/?cid=nrcs142p2_053951

http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/contactus/?cid=nrcs142p2_053951

alternative means for communication of program information (Braille, large print,audiotape, etc.) should contact USDA's TARGET Center at (202) 720-2600 (voiceand TDD). To file a complaint of discrimination, write to USDA, Director, Office ofCivil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 orcall (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunityprovider and employer.

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ContentsPreface.................................................................................................................... 2How Soil Surveys Are Made..................................................................................5Soil Map.................................................................................................................. 8

Soil Map................................................................................................................9Legend................................................................................................................10Map Unit Legend................................................................................................ 11Map Unit Descriptions.........................................................................................11

Travis County, Texas.......................................................................................13Bh—Bergstrom soils and Urban land, 0 to 2 percent slopes.......................13DuA—Heaton soils and Urban land, 0 to 2 percent slopes......................... 14Fs—Oakalla soils, 0 to 1 percent slopes, channeled, frequently flooded....15HsD—Houston Black soils and Urban land, 0 to 8 percent slopes............. 17Tw—Tinn clay, 0 to 1 percent slopes, frequently flooded............................ 18

Soil Information for All Uses...............................................................................20Soil Reports........................................................................................................ 20

Soil Physical Properties.................................................................................. 20Engineering Properties (La Loma Trail Project).......................................... 20

References............................................................................................................26

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How Soil Surveys Are MadeSoil surveys are made to provide information about the soils and miscellaneousareas in a specific area. They include a description of the soils and miscellaneousareas and their location on the landscape and tables that show soil properties andlimitations affecting various uses. Soil scientists observed the steepness, length,and shape of the slopes; the general pattern of drainage; the kinds of crops andnative plants; and the kinds of bedrock. They observed and described many soilprofiles. A soil profile is the sequence of natural layers, or horizons, in a soil. Theprofile extends from the surface down into the unconsolidated material in which thesoil formed or from the surface down to bedrock. The unconsolidated material isdevoid of roots and other living organisms and has not been changed by otherbiological activity.

Currently, soils are mapped according to the boundaries of major land resourceareas (MLRAs). MLRAs are geographically associated land resource units thatshare common characteristics related to physiography, geology, climate, waterresources, soils, biological resources, and land uses (USDA, 2006). Soil surveyareas typically consist of parts of one or more MLRA.

The soils and miscellaneous areas in a survey area occur in an orderly pattern thatis related to the geology, landforms, relief, climate, and natural vegetation of thearea. Each kind of soil and miscellaneous area is associated with a particular kindof landform or with a segment of the landform. By observing the soils andmiscellaneous areas in the survey area and relating their position to specificsegments of the landform, a soil scientist develops a concept, or model, of how theywere formed. Thus, during mapping, this model enables the soil scientist to predictwith a considerable degree of accuracy the kind of soil or miscellaneous area at aspecific location on the landscape.

Commonly, individual soils on the landscape merge into one another as theircharacteristics gradually change. To construct an accurate soil map, however, soilscientists must determine the boundaries between the soils. They can observe onlya limited number of soil profiles. Nevertheless, these observations, supplementedby an understanding of the soil-vegetation-landscape relationship, are sufficient toverify predictions of the kinds of soil in an area and to determine the boundaries.

Soil scientists recorded the characteristics of the soil profiles that they studied. Theynoted soil color, texture, size and shape of soil aggregates, kind and amount of rockfragments, distribution of plant roots, reaction, and other features that enable themto identify soils. After describing the soils in the survey area and determining theirproperties, the soil scientists assigned the soils to taxonomic classes (units).Taxonomic classes are concepts. Each taxonomic class has a set of soilcharacteristics with precisely defined limits. The classes are used as a basis forcomparison to classify soils systematically. Soil taxonomy, the system of taxonomicclassification used in the United States, is based mainly on the kind and characterof soil properties and the arrangement of horizons within the profile. After the soil

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scientists classified and named the soils in the survey area, they compared theindividual soils with similar soils in the same taxonomic class in other areas so thatthey could confirm data and assemble additional data based on experience andresearch.

The objective of soil mapping is not to delineate pure map unit components; theobjective is to separate the landscape into landforms or landform segments thathave similar use and management requirements. Each map unit is defined by aunique combination of soil components and/or miscellaneous areas in predictableproportions. Some components may be highly contrasting to the other componentsof the map unit. The presence of minor components in a map unit in no waydiminishes the usefulness or accuracy of the data. The delineation of suchlandforms and landform segments on the map provides sufficient information for thedevelopment of resource plans. If intensive use of small areas is planned, onsiteinvestigation is needed to define and locate the soils and miscellaneous areas.

Soil scientists make many field observations in the process of producing a soil map.The frequency of observation is dependent upon several factors, including scale ofmapping, intensity of mapping, design of map units, complexity of the landscape,and experience of the soil scientist. Observations are made to test and refine thesoil-landscape model and predictions and to verify the classification of the soils atspecific locations. Once the soil-landscape model is refined, a significantly smallernumber of measurements of individual soil properties are made and recorded.These measurements may include field measurements, such as those for color,depth to bedrock, and texture, and laboratory measurements, such as those forcontent of sand, silt, clay, salt, and other components. Properties of each soiltypically vary from one point to another across the landscape.

Observations for map unit components are aggregated to develop ranges ofcharacteristics for the components. The aggregated values are presented. Directmeasurements do not exist for every property presented for every map unitcomponent. Values for some properties are estimated from combinations of otherproperties.

While a soil survey is in progress, samples of some of the soils in the area generallyare collected for laboratory analyses and for engineering tests. Soil scientistsinterpret the data from these analyses and tests as well as the field-observedcharacteristics and the soil properties to determine the expected behavior of thesoils under different uses. Interpretations for all of the soils are field tested throughobservation of the soils in different uses and under different levels of management.Some interpretations are modified to fit local conditions, and some newinterpretations are developed to meet local needs. Data are assembled from othersources, such as research information, production records, and field experience ofspecialists. For example, data on crop yields under defined levels of managementare assembled from farm records and from field or plot experiments on the samekinds of soil.

Predictions about soil behavior are based not only on soil properties but also onsuch variables as climate and biological activity. Soil conditions are predictable overlong periods of time, but they are not predictable from year to year. For example,soil scientists can predict with a fairly high degree of accuracy that a given soil willhave a high water table within certain depths in most years, but they cannot predictthat a high water table will always be at a specific level in the soil on a specific date.

After soil scientists located and identified the significant natural bodies of soil in thesurvey area, they drew the boundaries of these bodies on aerial photographs and

Custom Soil Resource Report

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identified each as a specific map unit. Aerial photographs show trees, buildings,fields, roads, and rivers, all of which help in locating boundaries accurately.


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Soil MapThe soil map section includes the soil map for the defined area of interest, a list ofsoil map units on the map and extent of each map unit, and cartographic symbolsdisplayed on the map. Also presented are various metadata about data used toproduce the map, and a description of each soil map unit.

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Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 14N WGS840 350 700 1400 2100

Feet0 100 200 400 600

MetersMap Scale: 1:7,950 if printed on A portrait (8.5" x 11") sheet.

Soil Map may not be valid at this scale.

MAP LEGEND MAP INFORMATION

Area of Interest (AOI)Area of Interest (AOI)

SoilsSoil Map Unit Polygons

Soil Map Unit Lines

Soil Map Unit Points

Special Point FeaturesBlowout

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 FeaturesStreams and Canals

TransportationRails

Interstate Highways

US Routes

Major Roads

Local Roads

BackgroundAerial Photography

The soil surveys that comprise your AOI were mapped at1:24,000.

Warning: Soil Map may not be valid at this scale.

Enlargement of maps beyond the scale of mapping can causemisunderstanding of the detail of mapping and accuracy of soilline placement. The maps do not show the small areas ofcontrasting soils that could have been shown at a more detailedscale.

Please rely on the bar scale on each map sheet for mapmeasurements.

Source of Map: Natural Resources Conservation ServiceWeb Soil Survey URL:Coordinate System: Web Mercator (EPSG:3857)

Maps from the Web Soil Survey are based on the Web Mercatorprojection, which preserves direction and shape but distortsdistance and area. A projection that preserves area, such as theAlbers equal-area conic projection, should be used if moreaccurate calculations of distance or area are required.

This product is generated from the USDA-NRCS certified data asof the version date(s) listed below.

Soil Survey Area: Travis County, TexasSurvey Area Data: Version 17, Sep 19, 2016

Soil map units are labeled (as space allows) for map scales1:50,000 or larger.

Date(s) aerial images were photographed: Feb 6, 2011—Feb 10,2011

The orthophoto or other base map on which the soil lines werecompiled and digitized probably differs from the backgroundimagery displayed on these maps. As a result, some minorshifting of map unit boundaries may be evident.


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Map Unit Legend

Travis County, Texas (TX453)

Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI

Bh Bergstrom soils and Urbanland, 0 to 2 percent slopes

103.0 57.6%

DuA Heaton soils and Urban land, 0to 2 percent slopes

4.4 2.5%

Fs Oakalla soils, 0 to 1 percentslopes, channeled, frequentlyflooded

1.1 0.6%

HsD Houston Black soils and Urbanland, 0 to 8 percent slopes

48.6 27.1%

Tw Tinn clay, 0 to 1 percent slopes,frequently flooded

21.8 12.2%

Totals for Area of Interest 178.9 100.0%

Map Unit DescriptionsThe map units delineated on the detailed soil maps in a soil survey represent thesoils or miscellaneous areas in the survey area. The map unit descriptions, alongwith 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 moremajor kinds of soil or miscellaneous areas. A map unit is identified and namedaccording to the taxonomic classification of the dominant soils. Within a taxonomicclass there are precisely defined limits for the properties of the soils. On thelandscape, however, the soils are natural phenomena, and they have thecharacteristic variability of all natural phenomena. Thus, the range of someobserved 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 withoutincluding areas of other taxonomic classes. Consequently, every map unit is madeup of the soils or miscellaneous areas for which it is named and some minorcomponents 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 themap unit, and thus they do not affect use and management. These are callednoncontrasting, or similar, components. They may or may not be mentioned in aparticular map unit description. Other minor components, however, have propertiesand behavioral characteristics divergent enough to affect use or to require differentmanagement. These are called contrasting, or dissimilar, components. Theygenerally are in small areas and could not be mapped separately because of thescale used. Some small areas of strongly contrasting soils or miscellaneous areasare identified by a special symbol on the maps. If included in the database for agiven area, the contrasting minor components are identified in the map unitdescriptions along with some characteristics of each. A few areas of minorcomponents may not have been observed, and consequently they are notmentioned in the descriptions, especially where the pattern was so complex that it


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was impractical to make enough observations to identify all the soils andmiscellaneous areas on the landscape.

The presence of minor components in a map unit in no way diminishes theusefulness or accuracy of the data. The objective of mapping is not to delineatepure taxonomic classes but rather to separate the landscape into landforms orlandform segments that have similar use and management requirements. Thedelineation of such segments on the map provides sufficient information for thedevelopment of resource plans. If intensive use of small areas is planned, however,onsite investigation is needed to define and locate the soils and miscellaneousareas.

An identifying symbol precedes the map unit name in the map unit descriptions.Each description includes general facts about the unit and gives important soilproperties and qualities.

Soils that have profiles that are almost alike make up a soil series. Except fordifferences in texture of the surface layer, all the soils of a series have majorhorizons 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 thebasis of such differences, a soil series is divided into soil phases. Most of the areasshown on the detailed soil maps are phases of soil series. The name of a soil phasecommonly indicates a feature that affects use or management. For example, Alphasilt 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 intricatepattern 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 similarin 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 ormiscellaneous areas that are shown as one unit on the maps. Because of presentor anticipated uses of the map units in the survey area, it was not consideredpractical or necessary to map the soils or miscellaneous areas separately. Thepattern and relative proportion of the soils or miscellaneous areas are somewhatsimilar. Alpha-Beta association, 0 to 2 percent slopes, is an example.

An undifferentiated group is made up of two or more soils or miscellaneous areasthat could be mapped individually but are mapped as one unit because similarinterpretations can be made for use and management. The pattern and proportionof the soils or miscellaneous areas in a mapped area are not uniform. An area canbe made up of only one of the major soils or miscellaneous areas, or it can be madeup 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 soilmaterial and support little or no vegetation. Rock outcrop is an example.


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Travis County, Texas

Bh—Bergstrom soils and Urban land, 0 to 2 percent slopes

Map Unit SettingNational map unit symbol: f52hElevation: 0 to 4,000 feetMean annual precipitation: 8 to 60 inchesMean annual air temperature: 54 to 73 degrees FFrost-free period: 180 to 310 daysFarmland classification: Not prime farmland

Map Unit CompositionBergstrom and similar soils: 58 percentUrban land: 35 percentMinor components: 7 percentEstimates are based on observations, descriptions, and transects of the mapunit.

Description of Bergstrom

SettingLandform: Flood-plain stepsLandform position (three-dimensional): TreadDown-slope shape: LinearAcross-slope shape: LinearParent material: Loamy alluvium of holocene age derived from mixede sources

Typical profileH1 - 0 to 20 inches: silty clay loamH2 - 20 to 60 inches: silt loamH3 - 60 to 80 inches: silty clay loam

Properties and qualitiesSlope: 0 to 2 percentDepth to restrictive feature: More than 80 inchesNatural drainage class: Well drainedCapacity of the most limiting layer to transmit water (Ksat): Moderately high to

high (0.57 to 1.98 in/hr)Depth to water table: More than 80 inchesFrequency of flooding: RareFrequency of ponding: NoneCalcium carbonate, maximum in profile: 10 percentGypsum, maximum in profile: 2 percentAvailable water storage in profile: High (about 10.8 inches)

Interpretive groupsLand capability classification (irrigated): None specifiedLand capability classification (nonirrigated): 2eHydrologic Soil Group: BHydric soil rating: No

Description of Urban Land

Typical profileH1 - 0 to 40 inches: variable


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Interpretive groupsLand capability classification (irrigated): None specifiedLand capability classification (nonirrigated): 8sHydrologic Soil Group: DHydric soil rating: No

Minor Components

UnnamedPercent of map unit: 7 percentHydric soil rating: No

DuA—Heaton soils and Urban land, 0 to 2 percent slopes

Map Unit SettingNational map unit symbol: f54xElevation: 0 to 4,000 feetMean annual precipitation: 8 to 60 inchesMean annual air temperature: 54 to 73 degrees FFrost-free period: 180 to 310 daysFarmland classification: Not prime farmland

Map Unit CompositionHeaton and similar soils: 52 percentUrban land: 25 percentMinor components: 23 percentEstimates are based on observations, descriptions, and transects of the mapunit.

Description of Heaton

SettingLandform: Stream terracesLandform position (three-dimensional): TreadDown-slope shape: LinearAcross-slope shape: LinearParent material: Loamy alluvium of holocen age derived from mixed sources

Typical profileH1 - 0 to 25 inches: loamy fine sandH3 - 25 to 60 inches: sandy clay loam

Properties and qualitiesSlope: 0 to 2 percentDepth to restrictive feature: More than 80 inchesNatural drainage class: Well drainedCapacity of the most limiting layer to transmit water (Ksat): Moderately high to

high (0.57 to 1.98 in/hr)Depth to water table: More than 80 inchesFrequency of flooding: None


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Frequency of ponding: NoneAvailable water storage in profile: Moderate (about 6.5 inches)

Interpretive groupsLand capability classification (irrigated): None specifiedLand capability classification (nonirrigated): 3eHydrologic Soil Group: BHydric soil rating: No




Minor Components


Fs—Oakalla soils, 0 to 1 percent slopes, channeled, frequently flooded

Map Unit SettingNational map unit symbol: 2t26xElevation: 370 to 1,450 feetMean annual precipitation: 30 to 35 inchesMean annual air temperature: 66 to 69 degrees FFrost-free period: 210 to 250 daysFarmland classification: Not prime farmland

Map Unit CompositionOakalla, channeled, and similar soils: 90 percentMinor components: 10 percentEstimates are based on observations, descriptions, and transects of the mapunit.

Description of Oakalla, Channeled

SettingLandform: Flood plainsLandform position (three-dimensional): TreadDown-slope shape: LinearAcross-slope shape: LinearParent material: Loamy alluvium derived from limestone


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Typical profileAp - 0 to 8 inches: silty clay loamAk - 8 to 23 inches: silty clay loamBk1 - 23 to 53 inches: silty clay loamBk2 - 53 to 80 inches: silty clay loam

Properties and qualitiesSlope: 0 to 1 percentDepth to restrictive feature: More than 80 inchesNatural drainage class: Well drainedRunoff class: NegligibleCapacity of the most limiting layer to transmit water (Ksat): Moderately high to

high (0.20 to 1.98 in/hr)Depth to water table: More than 80 inchesFrequency of flooding: FrequentFrequency of ponding: NoneCalcium carbonate, maximum in profile: 60 percentSalinity, maximum in profile: Nonsaline to very slightly saline (0.0 to 2.0

mmhos/cm)Available water storage in profile: Moderate (about 8.8 inches)

Interpretive groupsLand capability classification (irrigated): 5wLand capability classification (nonirrigated): 5wHydrologic Soil Group: BEcological site: Loamy Bottomland 29-35" PZ (R081CY561TX)Hydric soil rating: No

Minor Components

Rock outcropPercent of map unit: 5 percentLandform: ChannelsDown-slope shape: LinearAcross-slope shape: ConvexHydric soil rating: No

DevPercent of map unit: 4 percentLandform: Flood plainsLandform position (three-dimensional): TreadDown-slope shape: LinearAcross-slope shape: ConcaveEcological site: DRAW 19-31" PZ (R081BY682TX)Hydric soil rating: No

Unnamed, hydricPercent of map unit: 1 percentLandform: Depressions, flood-plain stepsLandform position (three-dimensional): TreadDown-slope shape: Concave, linearAcross-slope shape: ConcaveHydric soil rating: Yes


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HsD—Houston Black soils and Urban land, 0 to 8 percent slopes

Map Unit SettingNational map unit symbol: f65fElevation: 0 to 4,000 feetMean annual precipitation: 8 to 60 inchesMean annual air temperature: 54 to 73 degrees FFrost-free period: 180 to 310 daysFarmland classification: Not prime farmland

Map Unit CompositionHouston black and similar soils: 56 percentUrban land: 30 percentMinor components: 14 percentEstimates are based on observations, descriptions, and transects of the mapunit.

Description of Houston Black

SettingLandform: RidgesLandform position (two-dimensional): Summit, shoulderLandform position (three-dimensional): InterfluveMicrofeatures of landform position: Linear gilgaiDown-slope shape: ConvexAcross-slope shape: ConvexParent material: Residuum weathered from calcareous shale of taylor marl and

eagleford shale

Typical profileH1 - 0 to 8 inches: clayH2 - 8 to 30 inches: clayH3 - 30 to 80 inches: clay

Properties and qualitiesSlope: 0 to 8 percentDepth to restrictive feature: More than 80 inchesNatural drainage class: Moderately well drainedCapacity of the most limiting layer to transmit water (Ksat): Very low to moderately

low (0.00 to 0.06 in/hr)Depth to water table: More than 80 inchesFrequency of flooding: NoneFrequency of ponding: NoneCalcium carbonate, maximum in profile: 40 percentSalinity, maximum in profile: Nonsaline to slightly saline (0.0 to 4.0 mmhos/cm)Sodium adsorption ratio, maximum in profile: 2.0Available water storage in profile: Moderate (about 8.6 inches)

Interpretive groupsLand capability classification (irrigated): None specifiedLand capability classification (nonirrigated): 3e


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Hydrologic Soil Group: DHydric soil rating: No




Minor Components


Tw—Tinn clay, 0 to 1 percent slopes, frequently flooded

Map Unit SettingNational map unit symbol: 2vtgrElevation: 330 to 750 feetMean annual precipitation: 35 to 47 inchesMean annual air temperature: 63 to 68 degrees FFrost-free period: 226 to 263 daysFarmland classification: Not prime farmland

Map Unit CompositionTinn and similar soils: 85 percentMinor components: 15 percentEstimates are based on observations, descriptions, and transects of the mapunit.

Description of Tinn

SettingLandform: Flood plainsLandform position (three-dimensional): TreadMicrofeatures of landform position: Circular gilgaiDown-slope shape: LinearAcross-slope shape: ConcaveParent material: Calcareous clayey alluvium

Typical profileA - 0 to 17 inches: clayBss - 17 to 57 inches: clayBkssy - 57 to 80 inches: clay


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Properties and qualitiesSlope: 0 to 1 percentDepth to restrictive feature: More than 80 inchesNatural drainage class: Moderately well drainedRunoff class: HighCapacity of the most limiting layer to transmit water (Ksat): Very low to moderately

low (0.00 to 0.06 in/hr)Depth to water table: More than 80 inchesFrequency of flooding: FrequentFrequency of ponding: NoneCalcium carbonate, maximum in profile: 25 percentGypsum, maximum in profile: 2 percentSalinity, maximum in profile: Nonsaline to very slightly saline (0.0 to 2.0

mmhos/cm)Sodium adsorption ratio, maximum in profile: 2.0Available water storage in profile: Moderate (about 8.4 inches)

Interpretive groupsLand capability classification (irrigated): None specifiedLand capability classification (nonirrigated): 5wHydrologic Soil Group: DEcological site: Clayey Bottomland 28-40" PZ (R086AY198TX)Hydric soil rating: No

Minor Components

WhitesboroPercent of map unit: 10 percentLandform: Flood plainsMicrofeatures of landform position: Circular gilgaiDown-slope shape: LinearAcross-slope shape: ConcaveEcological site: Loamy Bottomland 28-40" PZ (R086AY203TX)Hydric soil rating: No

GladewaterPercent of map unit: 5 percentLandform: Flood plainsDown-slope shape: ConcaveAcross-slope shape: ConcaveEcological site: Clayey Bottomland 28-40" PZ (R086AY198TX)Hydric soil rating: Yes


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Soil Information for All Uses

Soil ReportsThe Soil Reports section includes various formatted tabular and narrative reports(tables) containing data for each selected soil map unit and each component ofeach unit. No aggregation of data has occurred as is done in reports in the SoilProperties and Qualities and Suitabilities and Limitations sections.

The reports contain soil interpretive information as well as basic soil properties andqualities. A description of each report (table) is included.

Soil Physical Properties

This folder contains a collection of tabular reports that present soil physicalproperties. The reports (tables) include all selected map units and components foreach map unit. Soil physical properties are measured or inferred from directobservations in the field or laboratory. Examples of soil physical properties includepercent clay, organic matter, saturated hydraulic conductivity, available watercapacity, and bulk density.

Engineering Properties (La Loma Trail Project)

This table gives the engineering classifications and the range of engineeringproperties for the layers of each soil in the survey area.

Hydrologic soil group is a group of soils having similar runoff potential under similarstorm and cover conditions. The criteria for determining Hydrologic soil group isfound in the National Engineering Handbook, Chapter 7 issued May 2007(http://directives.sc.egov.usda.gov/OpenNonWebContent.aspx?content=17757.wba).Listing HSGs by soil map unit component and not by soil series is a new concept forthe engineers. Past engineering references contained lists of HSGs by soil series.Soil series are continually being defined and redefined, and the list of soil seriesnames changes so frequently as to make the task of maintaining a single nationallist virtually impossible. Therefore, the criteria is now used to calculate the HSGusing the component soil properties and no such national series lists will bemaintained. All such references are obsolete and their use should be discontinued.Soil properties that influence runoff potential are those that influence the minimumrate of infiltration for a bare soil after prolonged wetting and when not frozen. Theseproperties are depth to a seasonal high water table, saturated hydraulic conductivityafter prolonged wetting, and depth to a layer with a very slow water transmission

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rate. Changes in soil properties caused by land management or climate changesalso cause the hydrologic soil group to change. The influence of ground cover istreated independently. There are four hydrologic soil groups, A, B, C, and D, andthree dual groups, A/D, B/D, and C/D. In the dual groups, the first letter is fordrained areas and the second letter is for undrained areas.

The four hydrologic soil groups are described in the following paragraphs:

Group A. Soils having a high infiltration rate (low runoff potential) when thoroughlywet. These consist mainly of deep, well drained to excessively drained sands orgravelly sands. These soils have a high rate of water transmission.

Group B. Soils having a moderate infiltration rate when thoroughly wet. Theseconsist chiefly of moderately deep or deep, moderately well drained or well drainedsoils that have moderately fine texture to moderately coarse texture. These soilshave a moderate rate of water transmission.

Group C. Soils having a slow infiltration rate when thoroughly wet. These consistchiefly of soils having a layer that impedes the downward movement of water orsoils of moderately fine texture or fine texture. These soils have a slow rate of watertransmission.

Group D. Soils having a very slow infiltration rate (high runoff potential) whenthoroughly wet. These consist chiefly of clays that have a high shrink-swellpotential, soils that have a high water table, soils that have a claypan or clay layer ator near the surface, and soils that are shallow over nearly impervious material.These soils have a very slow rate of water transmission.

Depth to the upper and lower boundaries of each layer is indicated.

Texture is given in the standard terms used by the U.S. Department of Agriculture.These terms are defined according to percentages of sand, silt, and clay in thefraction of the soil that is less than 2 millimeters in diameter. "Loam," for example, issoil that is 7 to 27 percent clay, 28 to 50 percent silt, and less than 52 percent sand.If the content of particles coarser than sand is 15 percent or more, an appropriatemodifier is added, for example, "gravelly."

Classification of the soils is determined according to the Unified soil classificationsystem (ASTM, 2005) and the system adopted by the American Association ofState Highway and Transportation Officials (AASHTO, 2004).

The Unified system classifies soils according to properties that affect their use asconstruction material. Soils are classified according to particle-size distribution ofthe fraction less than 3 inches in diameter and according to plasticity index, liquidlimit, and organic matter content. Sandy and gravelly soils are identified as GW, GP,GM, GC, SW, SP, SM, and SC; silty and clayey soils as ML, CL, OL, MH, CH, andOH; and highly organic soils as PT. Soils exhibiting engineering properties of twogroups can have a dual classification, for example, CL-ML.

The AASHTO system classifies soils according to those properties that affectroadway construction and maintenance. In this system, the fraction of a mineral soilthat is less than 3 inches in diameter is classified in one of seven groups from A-1through A-7 on the basis of particle-size distribution, liquid limit, and plasticity index.Soils in group A-1 are coarse grained and low in content of fines (silt and clay). Atthe other extreme, soils in group A-7 are fine grained. Highly organic soils areclassified in group A-8 on the basis of visual inspection.

If laboratory data are available, the A-1, A-2, and A-7 groups are further classifiedas A-1-a, A-1-b, A-2-4, A-2-5, A-2-6, A-2-7, A-7-5, or A-7-6. As an additionalrefinement, the suitability of a soil as subgrade material can be indicated by a group


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index number. Group index numbers range from 0 for the best subgrade material to20 or higher for the poorest.

Percentage of rock fragments larger than 10 inches in diameter and 3 to 10 inchesin diameter are indicated as a percentage of the total soil on a dry-weight basis. Thepercentages are estimates determined mainly by converting volume percentage inthe field to weight percentage. Three values are provided to identify the expectedLow (L), Representative Value (R), and High (H).

Percentage (of soil particles) passing designated sieves is the percentage of the soilfraction less than 3 inches in diameter based on an ovendry weight. The sieves,numbers 4, 10, 40, and 200 (USA Standard Series), have openings of 4.76, 2.00,0.420, and 0.074 millimeters, respectively. Estimates are based on laboratory testsof soils sampled in the survey area and in nearby areas and on estimates made inthe field. Three values are provided to identify the expected Low (L), RepresentativeValue (R), and High (H).

Liquid limit and plasticity index (Atterberg limits) indicate the plasticitycharacteristics of a soil. The estimates are based on test data from the survey areaor from nearby areas and on field examination. Three values are provided to identifythe expected Low (L), Representative Value (R), and High (H).

References:

American Association of State Highway and Transportation Officials (AASHTO).2004. Standard specifications for transportation materials and methods of samplingand testing. 24th edition.

American Society for Testing and Materials (ASTM). 2005. Standard classification ofsoils for engineering purposes. ASTM Standard D2487-00.


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Absence of an entry indicates that the data were not estimated. The asterisk '*' denotes the representative texture; otherpossible textures follow the dash. The criteria for determining the hydrologic soil group for individual soil components isfound in the National Engineering Handbook, Chapter 7 issued May 2007(http://directives.sc.egov.usda.gov/OpenNonWebContent.aspx?content=17757.wba). Three values are provided to identify the expected Low (L),Representative Value (R), and High (H).

Engineering Properties–Travis County, Texas

Map unit symbol andsoil name

Pct. ofmapunit

Hydrologic

group

Depth USDA texture Classification Pct Fragments Percentage passing sieve number— Liquidlimit

Plasticity index

Unified AASHTO >10inches

3-10inches

4 10 40 200

In L-R-H L-R-H L-R-H L-R-H L-R-H L-R-H L-R-H L-R-H

Bh—Bergstrom soilsand Urban land, 0 to2 percent slopes

Bergstrom 58 B 0-20 Silty clay loam CL A-6, A-7-6 0- 0- 0 0- 0- 0 95-98-100

95-98-100

95-98-100

85-92-99

30-38-46

11-18-25

20-60 Silt loam, silty clayloam

CL A-6, A-7-6 0- 0- 0 0- 0- 0 95-98-100

95-98-100

95-98-100

85-91-97

32-39-46

12-19-25

60-80 Silty clay loam CL A-6, A-7-6 0- 0- 0 0- 0- 0 95-98-100

95-98-100

95-98-100

85-91-97

30-38-45

11-18-25

Urban land 35 D 0-40 Variable — — — — — — — — — —

DuA—Heaton soilsand Urban land, 0 to2 percent slopes

Heaton 52 B 0-25 Loamy fine sand SM, SC A-2-4 0- 0- 0 0- 0- 0 95-98-100

95-98-100

70-80-90

15-23-30

16-18-20

NP-2 -3

25-60 Sandy clay loam,fine sandy loam

CL, SC A-4, A-6 0- 0- 0 0- 0- 0 98-99-100

95-98-100

75-87-98

36-51-65

20-28-35

8-15-22



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Pct. ofmapunit

Hydrologic

group


Plasticity index


3-10inches

4 10 40 200


Fs—Oakalla soils, 0 to1 percent slopes,channeled,frequently flooded

Oakalla, channeled 90 B 0-8 Silty clay loam CH, CL A-6, A-7-6 0- 0- 0 0- 0- 0 91-98-100

82-96-100

76-95-100

67-85-97

35-49-58

13-24-30

8-23 Loam, clay loam,silty clay loam,silty clay, clay

CL, CH A-4, A-6,A-7-6

0- 0- 0 0- 0- 0 91-98-100

82-96-100

73-95-100

64-85-100

28-43-62

10-17-38

23-53 Clay loam, silty clayloam, clay, loam

CL, CH A-4, A-6,A-7-6

0- 0- 0 0- 0- 0 84-90-100

83-89-100

74-89-100

65-79-100

25-38-56

8-16-35

53-80 Loam, clay loam,silty clay loam,fine sandy loam,clay

CL, CH,ML, CL-ML

A-4, A-6,A-7-6

0- 0- 0 0- 0- 0 84-90-100

83-89-100

70-89-100

61-79-100

21-38-56

2-16-35

HsD—Houston Blacksoils and Urbanland, 0 to 8 percentslopes

Houston black 56 D 0-8 Clay CH A-7-6 0- 0- 0 0- 0- 0 97-99-100

96-98-100

94-97-100

88-93-98

58-74-90

34-47-60

8-30 Clay, silty clay CH A-7-6 0- 0- 0 0- 0- 0 98-99-100

98-99-100

92-96-100

88-93-97

58-78-98

37-55-72

30-80 Clay, silty clay CH A-7-6 0- 0- 0 0- 0- 0 94-97-100

93-97-100

87-94-100

84-92-99

51-75-99

32-55-78



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Pct. ofmapunit

Hydrologic

group


Plasticity index


3-10inches

4 10 40 200


Tw—Tinn clay, 0 to 1percent slopes,frequently flooded

Tinn 85 D 0-17 Clay CH A-7, A-7-6 0- 0- 0 0- 0- 0 100-100-100

96-98-100

84-91-100

73-79-91

61-66-76

37-41-49

17-57 Silty clay, clay CH A-7, A-7-6 0- 0- 0 0- 0- 0 100-100-100

96-98-100

81-91-100

70-79-91

58-66-76

35-41-49

57-80 Silty clay, clay CH A-7, A-7-6 0- 0- 0 0- 0- 0 100-100-100

92-96-100

78-89-100

67-78-91

58-66-76

35-41-49


25

ReferencesAmerican Association of State Highway and Transportation Officials (AASHTO).2004. Standard specifications for transportation materials and methods of samplingand testing. 24th edition.

American Society for Testing and Materials (ASTM). 2005. Standard classification ofsoils for engineering purposes. ASTM Standard D2487-00.

Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification ofwetlands and deep-water habitats of the United States. U.S. Fish and WildlifeService 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 hydricsoils 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 formaking and interpreting soil surveys. 2nd edition. Natural Resources ConservationService, 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 ofAgriculture, 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 andDelaware Department of Natural Resources and Environmental Control, WetlandsSection.

United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps ofEngineers wetlands delineation manual. Waterways Experiment Station TechnicalReport 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

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http://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_054262






http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/home/?cid=nrcs142p2_053374

http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/home/?cid=nrcs142p2_053374

http://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/landuse/rangepasture/?cid=stelprdb1043084

http://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/landuse/rangepasture/?cid=stelprdb1043084

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 Handbook296. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053624

United States Department of Agriculture, Soil Conservation Service. 1961. Landcapability classification. U.S. Department of Agriculture Handbook 210. http://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052290.pdf


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http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/scientists/?cid=nrcs142p2_054242

http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/scientists/?cid=nrcs142p2_054242



http://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052290.pdf

http://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052290.pdf

Documents

APPENDIX D: NRCS SOIL REPORT · 2020-02-20 · Custom Soil Resource Report for Travis County, Natural Texas Resources Conservation Service January 18, 2017. ... color, national origin,