Field Book

for Describing and

Sampling Soils

Version 3.0

National Soil Survey Center

Natural Resources Conservation Service

U.S. Department of Agriculture

September 2012

USDA-NRCS i September 2012

ACKNOWLEDGMENTS

The science and knowledge in this document are distilled from the 

collective experience of thousands of dedicated soil scientists during 

the more than 100 years of the National Cooperative Soil Survey 

(NCSS) program. A special thanks is due to these largely unknown 

stewards of the natural resources of this nation.

Special thanks and recognition are extended to those who 

contributed extensively to the preparation and production of this 

book: the soil scientists from the NRCS and NCSS cooperators 

who reviewed and improved it; Tammy Umholtz for document 

preparation and graphics; and the NRCS Soil Science Division for 

funding it.

Proper citation for this document is:

Schoeneberger, P.J., D.A. Wysocki, E.C. Benham, and Soil 

Survey Staff. 2012. Field book for describing and sampling soils, 

Version 3.0. Natural Resources Conservation Service, National 

Soil Survey Center, Lincoln, NE.

Cover Photo: A polygenetic Calcidic Argiustoll with an A, Bt, Bk, 

2BC, 2C horizon sequence. This soil formed in Peoria Loess that 

blankets the fluvial Ash Hollow Formation of the Ogallala Group. It 

occurs in an undulating area of the Cheyenne Tablelands in northern 

Banner County, Nebraska. The scale is in meters. (Photo by Doug 

Wysocki, NRCS, Lincoln, NE, June 2011.)

Trade names are used solely to provide specific information. Mention of 

a trade name does not constitute a guarantee of the product by the U.S. 

Department of Agriculture nor does it imply endorsement by the Department 

or the Natural Resources Conservation Service over comparable products that 

are not named.

The U.S. Department of Agriculture (USDA) prohibits discrimination in 

all its programs and activities on the basis of race, color, national origin, 

age, disability, and where applicable, sex (including gender identity and 

expression), marital status, familial status, parental status, religion, sexual 

orientation, political beliefs, genetic information, reprisal, or because all or 

part of an individual’s income is derived from any public assistance program. 

(Not all prohibited bases apply to all programs.) Persons with disabilities who 

require alternative means for communication of program information (Braille, 

large print, audiotape, etc.) should contact USDA’s TARGET Center at (202) 

720-2600 (voice and TDD). To file a complaint of discrimination, write to: 

USDA, Assistant Secretary for Civil Rights, Office of the Assistant Secretary for 

Civil Rights, 1400 Independence Avenue, S.W., Stop 9410, Washington, D.C. 

20250-9410, or call toll-free at (866) 632-9992 (English) or (800) 877-8339 

(TDD) or (866) 377-8642 (English Federal-relay) or (800) 845-6136 (Spanish 

Federal-relay). USDA is an equal opportunity provider and employer.
USDA-NRCS ii September 2012

FOREWORD

Purpose: The following instructions, definitions, concepts, and 

codes are a field guide for making or reading soil descriptions 

and sampling soils as presently practiced in the USA. (Note: 

References cited in the Foreword are listed at the end of 

Chapter 1 [p. 1–31].)

Background: Soil description methodology was developed by soil 

scientists throughout the entire course of the soil survey. The 

USDA published small instruction booklets for field parties, 

including soil descriptions, in 1902–1904, 1906, and 1914. The 

first USDA guide for soil horizon identification and description 

was released in 1937 (Bureau of Chemistry and Soils, 1937). 

Dr. Roy Simonson and others later summarized and revised this 

information (Soil Survey Staff, 1951; Soil Survey Staff, 1962). 

Brief “color-book” inserts with shorthand notation were released 

by the Soil Conservation Service (Spartanburg, SC, 1961; 

Western Technical Center, Portland, OR, 1974). Previous Field 

Books were released in 1998 (Schoeneberger et al.) and 2002 

(Schoeneberger et al.). This is an updated Field Book version 

that summarizes current knowledge, includes updates since 

2002, and reflects changes in source documents.

Standards: This Field Book summarizes and updates current 

National Cooperative Soil Survey conventions for describing soils 

(Soil Survey Manual [Soil Survey Division Staff, 1993]; National 

Soil Survey Handbook [Soil Survey Staff, 2012d]; National Soil 

Information System (NASIS), release 6.2 [Soil Survey Staff, 

2012c]; and NASIS Data Dictionary [Soil Survey Staff, 2012a]). 

Some content is an abbreviation of primary sources.

Regarding Pedon PC and NASIS: The Field Book is a current, 

practical soil description guide for the soil science community. It 

is not a guide on “How To Use Pedon PC or NASIS.” Differences 

and linkages between soil science conventions, Pedon PC, 

NASIS, and older systems are shown, where reasonable to do 

so, as an aid for interpreting and converting archived data.

Standard procedures and terms for describing soils have 

changed and increased in recent years (e.g., redoximorphic 

features). Coincident with these changes has been the 

development and use of computer databases to store soil 

descriptions and associated information. The nature of 

databases, for better or worse, requires consistent and “correct” 

use of terms.

Sources: This Field Book draws from several primary sources: The 

Soil Survey Manual (Soil Survey Division Staff, 1993) and the 

National Soil Survey Handbook (NSSH), Parts 618 and 629 (Soil 
USDA-NRCS iii September 2012

Survey Staff, 2012d). Other important sources are footnoted 

throughout to give appropriate credit and encourage in-depth 

information review. Other material is unique to this book.

Brevity: In a field book, brevity is efficiency. Despite this book’s 

apparent length, the criteria, definitions, and concepts are 

condensed. We urge users to review the comprehensive 

information in original sources to avoid errors resulting from our 

brevity.

Measurement Units: For soil description, metric units are the 

scientific standard. Both NASIS and Pedon PC use metric units.

Format: The “Site Description” and “Profile Description” sections 

generally follow conventional profile description format and 

sequence (e.g., SCS-Form 232, December 1984). Some 

descriptors are arranged in a sequence more compatible 

with field description rather than data entry (e.g., Horizon 

Boundary is next to Horizon Depth, rather than at the end). 

The sequence followed differs somewhat from and does not

supersede convention for writing formal soil descriptions in soil 

survey reports or Official Soil Series Descriptions (e.g., National 

Soil Survey Handbook, Part 614; Soil Survey Staff, 2012d).

Codes: Shorthand notation is listed in the Code column for some 

descriptors. Long-standing conventional codes are retained 

because of widespread recognition. Some recent codes have 

been changed to make them more logical. Some data elements 

have different codes in various systems (e.g., conventional 

[Conv.] vs. NASIS vs. Pedon PC), and several columns may 

be shown to facilitate conversions. If only one code column is 

shown, it can be assumed that the conventional, NASIS, and 

Pedon PC codes are all the same.

Standard Terms vs. Creativity: Describe and record what you 

observe. Choice lists in this document are a minimal set of 

descriptors. Use additional descriptors, notes, and sketches to 

record pertinent information and/or features if no data element 

or choice list entry exists. Record such information as free-hand 

notes under Miscellaneous Field Notes.

Changes: Soil science is an evolving field. Changes to this 

Field Book should and will occur. Please send comments or 

suggestions to the Director, National Soil Survey Center, USDANRCS; 100 Centennial Mall North, Rm. 152; Lincoln, NE 68508-

3866.
USDA-NRCS iv September 2012

TABLE OF CONTENTS

ACKNOWLEDGMENTS. . . . . . . . . . . . . . . . . . . . . . . . . . i

FOREWORD. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii

SITE DESCRIPTION. . . . . . . . . . . . . . . . . . . . . . . . 1–1

Describer Name(s). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–1

Date. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–1

Climate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–1

(Weather Conditions, Air Temperature, Soil 

Temperature [Soil Temperature, Soil Temperature 

Depth])

Location. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–2

(Latitude, Longitude, Geodetic Datum)

Topographic Quadrangle. . . . . . . . . . . . . . . . . . . . . . . . . . 1–2

Soil Survey Site Identification Number (Site ID). . . . . . . 1–2

County FIPS Code. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–3

MLRA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–3

Transects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–3

(Transect ID, Stop Number, Interval)

Series or Component Name. . . . . . . . . . . . . . . . . . . . . . . . 1–4

(Map Unit Symbol, Photo #)

Geomorphic Information. . . . . . . . . . . . . . . . . . . . . . . . . . 1–4

Physiographic Location. . . . . . . . . . . . . . . . . . . . . . . . . . . 1–4

(Physiographic Division, Physiographic Province, 

Physiographic Section, State Physiographic Area, 

Local Physiographic/Geographic Name)

Geomorphic Description. . . . . . . . . . . . . . . . . . . . . . . . . . . 1–4

(Landscape, Landform, Microfeature, Anthropogenic 

Feature)

Surface Morphometry. . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–5

(Elevation, Slope Aspect, Slope Gradient, Slope 

Complexity, Relative Slope Segment Position, Slope 

Shape, Hillslope - Profile Position, Geomorphic 

Components [Hills, Terraces and Stepped Landforms, 

Mountains, Flat Plains], Microrelief, Drainage Pattern)

Water Status. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–11

Drainage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–11

Flooding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–13

(Frequency, Duration, Months)

Ponding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–14

(Frequency, Depth, Duration)

(Soil) Water State. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–14
USDA-NRCS v September 2012

Land Cover. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–16

(Earth Cover - Kind)

Vegetation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–17

(Plant Symbol, Plant Common Name, Plant Scientific 

Name, Vegetation Cover)

Parent Material. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–18

(Kind)

Bedrock. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–22

(Kind, Fracture Interval Class, Weathering Class, 

Depth [to Bedrock])

Lithostratigraphic Unit(s). . . . . . . . . . . . . . . . . . . . . . . . 1–25

Erosion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–25

(Kind, Degree Class)

Surface Fragments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–26

(Kind, Surface Fragment Class)

Diagnostic Horizons or Characteristics. . . . . . . . . . . . . . 1–28

(Kind, Depth, Soil Taxonomy Classification, ParticleSize Control Section)

Restriction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–30

(Kind, Hardness)

References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–31

PROFILE/PEDON DESCRIPTION. . . . . . . . . . . . . . 2–1

Observation Method. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–1

(Kind, Relative Size)

Horizon and Layer Designations. . . . . . . . . . . . . . . . . . . . 2–2

Master and Transitional Horizons and Layers. . . . . . . . . . . . 2–2

Horizon Suffixes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–4

Other Horizon Modifiers. . . . . . . . . . . . . . . . . . . . . . . . . . . 2–5

(Numerical Prefixes, Numerical Suffixes, The Prime, 

The Caret)

Horizon Depth. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–6

Horizon Thickness. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–6

Horizon Boundary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–6

(Distinctness, Topography)

Soil Color. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–8

Decision Flowchart for Describing Soil Colors. . . . . . . . . . . . 2–8

(Soil) Matrix Color. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–9

([Soil] Color, Moisture State, Location or Condition)

Redoximorphic Features—RMFs (Discussion). . . . . . . . . 2–10

Redoximorphic Features. . . . . . . . . . . . . . . . . . . . . . . . . 2–12

(Kind, Quantity, Size, Contrast, Color, Moisture 

State, Shape, Location, Hardness, Boundary)

Tabular List for Determination of Color Contrast. . . . . . . . . 2–16
USDA-NRCS vi September 2012

Mottles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–18

(Quantity, Size, Contrast, Color, Moisture State, 

Shape, Location)

Concentrations (Discussion). . . . . . . . . . . . . . . . . . . . . . 2–19

Concentrations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–20

(Kind, Quantity [Percent of Area Covered], Size, 

Contrast, Color, Moisture State, Shape, Location, 

Hardness, Boundary)

Pedogenic Carbonate Stages (Discussion). . . . . . . . . . . 2–28

(Development, Multiple Stages, Description)

Pedogenic Carbonate Development Stages -

 Fine Earth Matrix. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–30

Pedogenic Carbonate Development Stages -

 Coarse Fragment Matrix. . . . . . . . . . . . . . . . . . . . . . . . 2–31

Ped and Void Surface Features. . . . . . . . . . . . . . . . . . . . 2–32

(Kind, Amount, Continuity, Distinctness, Location, 

Color)

Soil Texture. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–36

Texture Class. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–37

(Soil) Textural Triangle (Fine Earth). . . . . . . . . . . . . . . . . . 2–38

Texture Modifiers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–38

(Quantity and Size, Compositional, Terms Used in 

Lieu of Texture)

Comparison of Particle Size Classes in Different

 Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–45

Rock and Other Fragments. . . . . . . . . . . . . . . . . . . . . . . 2–46

(Kind, Volume Percent, Size Classes and Descriptive 

Terms, Roundness, Hardness)

Artifacts (Human-derived). . . . . . . . . . . . . . . . . . . . . . . 2–49

(Kind, Quantity, Roundness, Shape, Cohesion, 

Penetrability, Persistence, Safety)

(Soil) Structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–52

(Type, Grade, Size)

Consistence. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–62

Rupture Resistance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–62

(Blocks, Peds, and Clods; Surface Crusts and Plates)

Cementing Agents. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–64

Manner of Failure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–65

Stickiness. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–66

Plasticity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–66

Penetration Resistance. . . . . . . . . . . . . . . . . . . . . . . . . . . 2–67

Penetration Orientation. . . . . . . . . . . . . . . . . . . . . . . . . . 2–68

Excavation Difficulty. . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–69
USDA-NRCS vii September 2012

Roots. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–70

(Quantity, Size, Quantity [graphic], Location)

Pores (Discussion). . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–73

Pores. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–73

(Quantity, Size, Shape, Vertical Continuity)

Cracks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–75

(Kind, Depth, Relative Frequency)

Soil Crusts (Discussion). . . . . . . . . . . . . . . . . . . . . . . . . 2–77

Soil Crusts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–79

(Kind)

Special Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–80

(Kind, Area [%] Occupied)

 Saturated Hydraulic Conductivity and Permeability

 (Discussion). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–81

Saturated Hydraulic Conductivity (Ksat). . . . . . . . . . . . . . 2–83

Permeability Classes. . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–85

Chemical Response. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–85

Reaction (pH). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–85

pH Method. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–86

Effervescence. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–87

(Class, Location, Chemical Agent)

Reduced Conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–88

(Dipyridyl - Location)

Salinity Class (Discussion). . . . . . . . . . . . . . . . . . . . . . . . 2–88

Salinity Class. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–89

Sodium Adsorption Ratio (SAR). . . . . . . . . . . . . . . . . . . . 2–89

Odor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–90

(Kind, Intensity)

Miscellaneous Field Notes. . . . . . . . . . . . . . . . . . . . . . . . 2–90

Minimum Data Set (for a soil description). . . . . . . . . . . 2–90

Pedon Description Data Sheet. . . . . . . . . . . . . . . . . . . . . 2–91

Pedon Description Example. . . . . . . . . . . . . . . . . . . . . . . 2–91

Pedon Description (Data Sheet – Blank). . . . . . . . . . . . . . 2–93

Pedon Description (Data Sheet – Example). . . . . . . . . . . . 2–95

Subaqueous Soils (SAS) Description. . . . . . . . . . . . . . . . 2–97

(Discussion, Description)

Bathymetry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–97

Site. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–98

Water Column Measurements. . . . . . . . . . . . . . . . . . . . . 2–102

Soil Profile Measurements and Description. . . . . . . . . . . . 2–103

Salinity (of Subaqueous Soils). . . . . . . . . . . . . . . . . . . . 2–106

Subaqueous Soils Profile Description Data Sheet. . . . . . . . 2–109

Subaqueous Soils Profile Description Example. . . . . . . . . 2–110
USDA-NRCS viii September 2012

Vibracore Sampling for Subaqueous Soils. . . . . . . . . . . 2–111

Discussion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–111

Site Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–111

Core Descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–111

Vibracore Log Sheet. . . . . . . . . . . . . . . . . . . . . . . . . . . 2–113

Vibracore Log Sheet Example. . . . . . . . . . . . . . . . . . . . . 2–114

References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–115

GEOMORPHIC DESCRIPTION. . . . . . . . . . . . . . . . . 3–1

Part I: Physiographic Location. . . . . . . . . . . . . . . . . . . . . 3–2

Part II: Geomorphic Description (Outline). . . . . . . . . . . 3–10

Part II: Geomorphic Description. . . . . . . . . . . . . . . . . . . 3–11

Comprehensive Lists. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–11

Geomorphic Environments and Other Groupings. . . . . . . . . 3–21

Part III: Surface Morphometry. . . . . . . . . . . . . . . . . . . . 3–39

References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–46

SOIL TAXONOMY. . . . . . . . . . . . . . . . . . . . . . . . . . 4–1

Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–1

Horizon and Layer Designations. . . . . . . . . . . . . . . . . . . . 4–1

Master and Transitional Horizons or Layers. . . . . . . . . . . . . . 4–1

Horizon Suffixes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–3

Horizon & Layer Designations Conversion Charts. . . . . . . . . 4–6

(Soil) Textural Triangle: Family Particle-Size Classes. . . . . . 4–10

Combined Textural Triangles: Fine Earth Texture Classes

 and Family Particle-Size Classes. . . . . . . . . . . . . . . . . . . 4–11

Soil Moisture Regimes. . . . . . . . . . . . . . . . . . . . . . . . . . . 4–11

Soil Temperature Regimes and Classes. . . . . . . . . . . . . . . 4–13

References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–14

GEOLOGY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–1

Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–1

Bedrock [Kind]. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–1

Rock Charts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–4

Igneous Rocks Chart. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–5

Metamorphic Rocks Chart. . . . . . . . . . . . . . . . . . . . . . . . . . 5–6

Sedimentary and Volcaniclastic Rocks. . . . . . . . . . . . . . . . . 5–7

Mass Movement (Mass Wasting) Types for Soil Survey. . . . . . 5–8

North American Geologic Time Scale. . . . . . . . . . . . . . . . . . 5–9

Till Terms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–10

Pyroclastic Terms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–11

Hierarchical Rank of Lithostratigraphic Units. . . . . . . . . 5–12

References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–13
USDA-NRCS ix September 2012

LOCATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–1

GPS Location. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–1

Public Land Survey. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–2

Townships and Ranges. . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–3

Sections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–3

Section Subdivisions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–4

Universal Transverse Mercator (UTM) Rectangular

 Coordinate System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–5

State Plane Coordinate System. . . . . . . . . . . . . . . . . . . . . 6–7

References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–7

MISCELLANEOUS. . . . . . . . . . . . . . . . . . . . . . . . . . 7–1

Percent of Area Covered. . . . . . . . . . . . . . . . . . . . . . . . . . 7–1

Ksat Class Estimate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–10

Soil Water Repellency (Discussion). . . . . . . . . . . . . . . . 7–14

Soil Water Repellency. . . . . . . . . . . . . . . . . . . . . . . . . . . 7–15

Measurement Equivalents and Conversions. . . . . . . . . . 7–16

Metric to English. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–16

English to Metric. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–17

Common Conversion Factors. . . . . . . . . . . . . . . . . . . . . . 7–18

Guide to Map Scales and Minimum Size Delineations. . . 7–21

Common Soil Map Symbols (Traditional). . . . . . . . . . . . 7–22

References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–28

SOIL SAMPLING. . . . . . . . . . . . . . . . . . . . . . . . . . . 8–1

Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–1

Types of Sampling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–1

(Horizon Sampling, Incremental Sampling, FixedDepth Sampling)

Sampling Techniques. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–3

Soil Sample Kinds. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–3

(Characterization Samples, Reference Samples)

Field Equipment Checklist. . . . . . . . . . . . . . . . . . . . . . . . . 8–4

Examples of Common Soil-Sampling Equipment. . . . . . . . 8–5

References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–6

INDEX. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–1

USDA-NRCS 1–1 September 2012

SITE DESCRIPTION

P.J. Schoeneberger, D.A. Wysocki, and E.C. Benham, NRCS, Lincoln, NE

DESCRIBER NAME(S)

NAME (or initials)—Record the observer(s) making the description; 

e.g., Erling E. Gamble or EEG.

DATE

MONTH/DAY/YEAR—Record the observation date. Use numeric 

notation (MM/DD/YYYY); e.g., 05/21/2012 (for May 21, 2012).

CLIMATE

Document the prevailing weather conditions at time of observation 

(a site condition that affects some field methods; e.g., Ksat). Record 

the major Weather Conditions and Air Temperature; e.g., Rain, 

27 °C.

Weather Conditions Code

sunny/clear SU

partly cloudy PC

overcast OV

rain RA

sleet SL

snow SN

AIR TEMPERATURE—Ambient air temperature at chest height 

(Celsius or Fahrenheit); e.g., 27 °C.

SOIL TEMPERATURE—Record the ambient Soil Temperature

and Depth at which it is determined; e.g., 22 °C, 50 cm. (NOTE: 

Soil taxonomy generally requires a 50 cm depth.) Soil temperature 

should only be determined from a freshly excavated surface that 

reflects the ambient soil conditions. Avoid surfaces equilibrated with 

air temperatures.

Soil Temperature—Record soil temperature (in °C or °F).

Soil Temperature Depth—Record depth at which the ambient 

soil temperature is measured; e.g., 50 cm.
USDA-NRCS 1–2 September 2012

LOCATION

Record precisely the point or site location (e.g., coordinates). 

Latitude and longitude as measured with a Global Positioning 

System (GPS) is the preferred descriptor. Report lat. and long. as 

degrees, minutes, seconds, and decimal seconds with direction, or 

as degrees and decimal degrees with direction. For example:

LATITUDE—46° 10' 19.38" N. or 46°.17205 N

LONGITUDE—95° 23' 47.16" W. or 95°.39643 W

GEODETIC DATUM (Horizontal_datum_name in NASIS)—A 

geodetic datum must accompany latitude and longitude. A geodetic 

datum is a model that defines the earth’s shape and size and serves 

as a latitude, longitude reference. Geodetic datum is a selectable 

GPS parameter. The preferred datum is the World Geodetic 

System 1984 (WGS-84). See “Location Section” for the complete 

geodetic datum list (p. 6–1).

Topographic maps display latitude and longitude and the geodetic 

datum employed (e.g., NAD 27, NAD 83). NOTE: NASIS requires 

latitude and longitude but allows other coordinate or location 

descriptors (e.g., UTM, State Plane Coordinates, Public Land Survey, 

Metes and Bounds). See “Location Section” (p. 6–1) for details.

TOPOGRAPHIC QUADRANGLE

Record the topographic map name (USGS quadrangle) that covers 

the observation site. Include scale (or “series”) and year printed; 

e.g., Pollard Creek-NW; TX; 1:24,000; 1972.

SOIL SURVEY SITE IDENTIFICATION NUMBER (SITE 

ID)

An identification number must be assigned if samples are collected 

(called User_Pedon_ID in NASIS). For the Kellogg Soil Survey 

Laboratory (Soil Survey Staff, 2011), this identifier consists of five 

required and one optional item.

Example: S2004WA27009

1) S indicates a sampled pedon. (“S” is omitted for pedons 

described but not sampled.)

2) 2004=calendar year sampled. Use 4-digit format; e.g., 

2012.

3) WA=two-character (alphabetic) Federal Information 

Processing Standards (FIPS 6-4) code for the state where 

sampled. For non-U.S. sites, use the Country Code from ISO 
USDA-NRCS 1–3 September 2012

3166-1 (International Organization for Standards, 2012b); 

e.g., CA for Canada.

4) 027=3-digit (numeric) FIPS code for county where 

sampled. For non-U.S. sites, use the appropriate two- or 

three-letter Administrative Subdivision code from ISO 

3166-2 (International Organization for Standards, 2012b) 

preceded by a 0 (zero) for two-letter codes; e.g., 0SK for 

Saskatchewan.

5) 009=consecutive pedon number for calendar year for 

county. This should be a 3-digit number. Use 0s (zeros) as 

placeholders when necessary; e.g., 9 becomes 009.

6) (Optional) A one-character “satellite” code can be used, if 

needed, to indicate a relationship between a primary pedon 

and satellite sample points; e.g., A in S2004WA027009A.

NOTE: Do not use spaces, dashes, or hypens (for database 

reasons). Use uppercase letters. A complete example is 

S2011OK061005A. A sampled soil characterization pedon collected 

in 2011 (2011) from Oklahoma (OK), Haskell County (061); this is 

a satellite pedon (A) of the fifth pedon (005) sampled in that county 

during 2011.

COUNTY FIPS CODE

The Federal Information Processing Standards (FIPS) code is a 

3-digit number for a county within a state in the U.S. (National 

Institute of Standards and Technology, 1990). Record the FIPS code 

for the county where the pedon or site occurs; e.g., 061 (Haskell 

County, OK). For non-U.S. sites, use the appropriate two- or threecharacter Country Code (International Organization for Standards–

Country Codes ISO 3166-1; 2012a or current date).

MLRA

This 1- to 3-digit number, often including one alpha character, 

identifies the Major Land Resource Area (NRCS, 2006); e.g., 58C

(Northern Rolling High Plains, Northeastern Part).

TRANSECTS

If a soil description is one of multiple transect points, record 

transect information; e.g., Transect ID, Stop Number, Interval, 

GPS Coordinates. NASIS also accommodates Transect Kind

(random point [–R], regular interval [–I]), Transect Section 

Method (biased [–B], random [–R]), Delineation Size (acres), 

Transect Direction (azimuth heading, e.g., 180°).
USDA-NRCS 1–4 September 2012

TRANSECT ID—A 4- or 5-digit number that identifies the transect; 

e.g., 0010 (the tenth transect within the survey area).

STOP NUMBER—If the sample/pedon is part of a transect, enter 

the 2-digit stop number along the transect; e.g., 07. (NOTE: NASIS 

allows up to 13 characters.)

INTERVAL—Record distance between observation points, compass 

bearing, and GPS coordinates, or draw a route map in the Field 

Notes (“User Defined Section”).

SERIES OR COMPONENT NAME

Assign the appropriate Soil Series or Map Unit Component name 

at time of description (e.g., Cecil). If unknown, enter SND for 

“Series Not Designated.” (In NASIS, “SND” is not used; assign an 

appropriate soil taxonomy class; e.g., Udorthents.) NOTE: A fieldassigned series name may change after additional data collection 

and lab analyses.

MAP UNIT SYMBOL—Record the soil map unit symbol (if known) 

for the sample site.

PHOTO #—If aerial imagery is used, record the photograph number 

that covers the sample site.

GEOMORPHIC INFORMATION

See the “Geomorphic Description Section” for complete lists 

(p. 3–1). Codes follow each listed choice. Conventionally, the 

entire name (e.g., mountains) is recorded.

PART 1: PHYSIOGRAPHIC LOCATION

Physiographic Division—e.g., Interior Plains or IN

Physiographic Province—e.g., Central Lowland or CL

Physiographic Section—e.g., Wisconsin Driftless Section or 

WDS

State Physiographic Area (Opt.)—e.g., Wisconsin Dells

Local Physiographic/Geographic Name (Opt.)—e.g., Bob’s 

Ridge

PART 2: GEOMORPHIC DESCRIPTION

Landscape—e.g., Foothills or FH

Landform—e.g., Ridge or RI

Microfeature—e.g., Mound or MO

Anthropogenic Feature—e.g., sanitary landfill or SL
USDA-NRCS 1–5 September 2012

PART 3: SURFACE MORPHOMETRY

Elevation—The height of a point on the earth’s surface relative 

to Mean Tide Level (MTL), formerly Mean Sea Level (MSL). 

Record units; e.g., 106 m or 348 ft. Recommended methods: 

interpolation from topographic map contours; altimeter reading 

tied to a known elevation datum. NOTE: An elevation value 

from a GPS can be recorded. Since the GPS elevation value 

typically is less certain than the latitude and longitude values, 

a correction for quantifiable errors is important (e.g., WAAS, 

or averaging many elevation values at a point by collecting 

a track log at the point and averaging the elevation values).

The latitude and longitude coordinates can be used to extract 

an elevation value from a DEM, if available. Note that all parts 

of a DEM cell return the same elevation value, so a higher 

resolution DEM is important for accuracy, especially if the point 

is on a steep slope.

Slope Aspect—The compass direction (in degrees and 

accounting for declination) that a slope faces, viewed 

downslope; e.g., 225°.

Slope Gradient—The ground surface inclination with respect 

to the horizontal plane; commonly called “slope.” Make 

observations downslope to avoid errors from clinometer types; 

e.g., 18%.

Slope Complexity—Describe the relative ground surface 

uniformity (smooth linear or curvilinear=simple or S) or 

irregularity (complex or C) downslope through the site; e.g., 

simple or S.
USDA-NRCS 1–6 September 2012

(adapted from Wysocki et al., 2000)

Simple vs. Complex

Relative Slope Segment Position (called geomorph_

slope_segment in NASIS)—If useful to subdivide long slopes, 

describe relative slope location of the area or point of interest.

Relative Slope 

Segment Position Code Criteria

lower third LT on lower third of slope

middle third MT on middle third of slope

upper third UT on upper third of slope

Slope Shape—Slope shape is described in two directions: up 

and down slope (perpendicular to the elevation contour) and 

across slope (along the elevation contour); e.g., Linear, Convex

or LV.

CV

L = Linear; V = Convex; C = Concave 

CC

VV VC

LV LC

CL

VL

LL

(adapted from Wysocki et al., 2000) 

Surface flow pathway
USDA-NRCS 1–7 September 2012

Hillslope-Profile Position (commonly called Hillslope 

Position)—Two-dimensional geomorphic descriptors that are 

segments (i.e., slope position) along a line that runs up and 

down slope; e.g., backslope or BS. This is best applied to 

points, not areas (e.g., map units).

Position Code

summit SU

shoulder SH

backslope BS

footslope FS

toeslope TS

Alluvium

SU SH

BS

FS 

TS TS

Channel FS

BS

SH SU

(adapted from Ruhe, 1975)
USDA-NRCS 1–8 September 2012

Geomorphic Component—Three-dimensional geomorphic 

descriptors for landforms, landform portions, or microfeatures 

that are applied to areas. Unique 3D descriptors are defined 

for Hills, Terraces and Stepped Landforms, Mountains, and Flat 

Plains; e.g., Hills-nose slope, or NS.

Hills NASIS Code

interfluve IF

crest CT

head slope HS

nose slope NS

side slope SS

free face FF

base slope BS

Lower order stream

base slope

side

slope

no

sl

se

ope

head

slope interfluve

base slope

Alluvial

fill

(Wysocki et al., 2012)

Colluviumand s ol pe al ul vui m

crest

free face (i.e., rock outcrop)

Higher order stream

Terraces and Stepped Landforms Code

riser RI

tread TR
USDA-NRCS 1–9 September 2012

TREAD

RISER

100 yr. Flood Zone

Annual

Flood

Plain

Uplands Terraces Flood-Plain Steps

(adapted from Wysocki et al., 2000)

Mountains Code

mountaintop MT

mountainflank MF

upper third—mountainflank UT

center third—mountainflank CT

lower third—mountainflank LT

free face FF

mountainbase MB
USDA-NRCS 1–10 September 2012

Flat Plains Code

dip DP

rise RI

talf TF

Microrelief—Small, relative elevation differences between 

adjacent areas on the earth’s surface; e.g., microhigh or MH or 

microlow or ML. 

Microrelief Code

microhigh MH

microlow ML

microslope MS

Drainage Pattern—The interconnected system of drainage 

channels on the land surface; also called drainage network. 

(See graphics, p. 3–45.) Can be recorded as a Text Note.

Drainage Pattern Code

annular AN

artificial AR

centripetal CE

dendritic DN

deranged DR

karst KA

parallel PA

pinnate PI

radial RA
USDA-NRCS 1–11 September 2012

Drainage Pattern Code

rectangular RE

thermokarst TH

trellis TR

WATER STATUS

DRAINAGE—An estimate of the natural drainage class (i.e., the 

prevailing wetness conditions) of a soil; e.g., somewhat poorly 

drained or SP.

Drainage Class Conv. Code

Subaqueous Drainage SA

Very Poorly Drained VP

Poorly Drained PD

Somewhat Poorly Drained SP

Moderately Well Drained MW

Well Drained WD

Somewhat Excessively Drained SE

Excessively Drained ED

The following definitions are from the traditional, national criteria 

for natural soil drainage classes (Soil Survey Division Staff, 1993). 

Specific regional definitions and criteria exist. (Contact an NRCS 

State office for specific local criteria.)

Subaqeous Drainage—Free water is above the soil surface. 

The occurrence of internal free water is permanent, and there 

is a positive water potential at the soil surface for more than 

21 hours each day. The soils have a peraquic soil moisture 

regime (proposed 2010; Soil Survey Staff revision online at 

soils.usda.gov/technical/manual/proposedchanges.html).

Very Poorly Drained—Water is at or near the soil surface 

during much of the growing season. Internal free water is 

very shallow and persistent or permanent. Unless the soil is 

artificially drained, most mesophytic crops cannot be grown. 

Commonly, the soil occupies a depression or is level. If rainfall 

is persistent or high, the soil can be sloping.

Poorly Drained—The soil is wet at shallow depths periodically 

during the growing season or remains wet for long periods. 

Internal free water is shallow or very shallow and common

or persistent. Unless the soil is artificially drained, most 

mesophytic crops cannot be grown. The soil, however, is not 
USDA-NRCS 1–12 September 2012

continuously wet directly below plow depth. The water table is 

commonly the result of a low or very low saturated hydraulic 

conductivity class or persistent rainfall or a combination of 

these factors.

Somewhat Poorly Drained—The soil is wet at a shallow 

depth for significant periods during the growing season. 

Internal free water is commonly shallow or moderately deep

and transitory or permanent. Unless the soil is artificially 

drained, the growth of most mesophytic plants is markedly 

restricted. The soil commonly has a low or very low saturated 

hydraulic conductivity class or a high water table, receives 

water from lateral flow or persistent rainfall, or is affected by 

some combination of these factors.

Moderately Well Drained—Water is removed from the soil 

somewhat slowly during some periods of the year. Internal free 

water commonly is moderately deep and may be transitory

or permanent. The soil is wet for only a short time within 

the rooting depth during the growing season but is wet long 

enough that most mesophytic crops are affected. The soil 

commonly has a moderately low or lower saturated hydraulic 

conductivity class within 1 meter of the surface, periodically 

receives high rainfall, or both.

Well Drained—Water is removed from the soil readily but not

rapidly. Internal free water commonly is deep or very deep; 

annual duration is not specified. Water is available to plants in 

humid regions during much of the growing season. Wetness 

does not inhibit growth of roots for significant periods during 

most growing seasons.

Somewhat Excessively Drained—Water is removed from the 

soil rapidly. Internal free water commonly is very deep or very 

rare. The soils are commonly coarse textured and have high

saturated hydraulic conductivity or are very shallow.

Excessively Drained—Water is removed from the soil very 

rapidly. Internal free water commonly is very deep or very 

rare. The soils are commonly coarse textured and have very 

high saturated hydraulic conductivity or are very shallow.
USDA-NRCS 1–13 September 2012

FLOODING—Estimate the Frequency, Duration, and Months

that flooding is expected; e.g., rare, brief, Jan.-March.

Frequency—Estimate how often, typically, flooding occurs.

Frequency 

Class Code

Criteria: estimated average 

number of flood events per

time span 1

None NO No reasonable chance

(e.g., <1 time in 500 years)

Very Rare VR ≥1 time in 500 years, but

<1 time in 100 years

Rare RA 1 to 5 times in 100 years

Occasional 2 OC >5 to 50 times in 100 years

Frequent 2, 3 FR >50 times in 100 years

Very Frequent 3, 4 VF >50% of all months in year

1 Flooding Frequency is an estimate of the current condition, 

whether natural or human influenced (such as by dams or 

artificial levees).

2 Historically, Occasional and Frequent classes could be combined 

and called Common; not recommended.

3 Very Frequent class takes precedence over Frequent, if 

applicable.

4 The Very Frequent class is intended for tidal flooding.

Duration—Estimate how long an area typically is flooded 

during a single flood event.

Duration Class

Code Criteria: estimated 

average duration per Conv. NASIS flood event

Extremely Brief EB EB 0.1 to < 4 hours

Very Brief VB VB 4 to < 48 hours

Brief BR B 2 to < 7 days

Long LO L 7 to < 30 days

Very Long VL VL ≥ 30 days

Months—Estimate the beginning and ending month(s) in a 

year that flooding generally occurs; e.g., Dec.-Feb.
USDA-NRCS 1–14 September 2012

PONDING—Estimate or monitor the Frequency, Depth, and 

Duration of standing water. A complete example is: occasional, 

50 cm, brief, Feb.-Apr.

Frequency—Estimate how often, typically, ponding occurs.

Frequency 

Class Code Criteria: estimated, average # of ponding events per time span

None NO <1 time in 100 years

Rare RA 1 to 5 times in 100 years

Occasional OC >5 to 50 times in 100 years

Frequent FR >50 times in 100 years

Depth—Estimate the average, representative depth of ponded 

water at the observation site and specify units; e.g., 1 ft or 

30 cm.

Duration—Estimate how long, typically, the ponding lasts.

Duration 

Class

Code Criteria: estimated, average 

Conv. NASIS time per ponding event

Very Brief VB VB <2 days

Brief BR B 2 to <7 days

Long LO L 7 to <30 days

Very Long VL VL ≥30 days

(SOIL) WATER STATE (called Observed Soil Moisture Status

in NASIS.)—Estimate the water state of the soil at the time of 

observation; e.g., wet, nonsatiated. Soil temperature must be 

above 0 °C. (Does not apply to frozen soil.)
USDA-NRCS 1–15 September 2012

Water 

State 

Class

Code Criteria: 

tension

Traditional Criteria: 

Conv. NASIS tension and field

Dry 1 D D >1500 kPa >15 bars of tension 2

(=1500 kPa)

Moist 1 M

M 4

≤1500 kPa 

to 

>1.0 kPa

(or

>0.5 kPa) 3

Former Usage: >1/3 

to 15 bars of tension

(33 to 1500 kPa) (field 

capacity to wilting 

point)

Wet W

≤1.0 kPa

(or

<0.5 kPa) 3

0-1/3 bar tension

(<33 kPa)

(field capacity or 

wetter)

 Wet:

 Non-

 satiated 5

WN

>0.00 and

≤1.0 kPa

(or

<0.5 kPa) 3

No Free Water:

Water films are 

visible; sand grains 

and peds glisten, 

but no free water is 

present

 Wet:

 Satiated 5 WS W ≤0.00 kPa

Free Water:

Free water easily 

visible

1 Additional subclasses of water state can be recognized for Dry

and Moist classes, if desired (Soil Survey Division Staff, 1993, 

p. 91).

2 Convention assumes 15 bars of tension as the wilting point for 

most annual agricultural row crops. Caution: Various perennials, 

shrubs, trees, and other native vegetation have a wilting point of 

as much as 66 bars tension (=6600 kPa) or more.

3 Use the 1 kPa limit for all textures, except those coarser than 

loamy fine sand (which use 0.5 kPa limit; Soil Survey Division 

Staff, 1993, p. 90).

4 NASIS uses the same three class names (Dry, Moist, Wet) but 

lumps the “wet: nonsatiated” subclass with the Moist class.

5 Satiation vs. Saturation: Satiation implies minor amounts of 

entrapped air in the smallest pores. True saturation implies no 

entrapped air. In Soil Taxonomy, “Saturation is ... zero or positive 

pressure in the soil ...” (Soil Survey Staff, 2010). Satiation, for 

practical purposes, is ≈ saturation. Temporal monitoring of a 

water table by piezometer or other accepted methods may be 

needed to verify saturation. Related terms used for classifying 

soils (i.e., soil taxonomy): Endosaturation is saturation in all 
USDA-NRCS 1–16 September 2012

layers to >200 cm (80 inches). Episaturation requires saturated 

layers that overlie unsaturated layers within the upper 2 m 

(80 inches). Anthric saturation, a variant of episaturation, is 

saturation due to management-induced flooding (e.g., for rice or 

cranberry production).

LAND COVER

LAND COVER (called EARTH COVER - KIND in NASIS)—Record 

the dominant land cover at the site; e.g., intermixed hardwoods and 

conifers. 

Kind 1 Code Kind 1 Code

ARTIFICIAL COVER (A)—Nonvegetative cover; due to 

human activity.

rural transportation - 

roads, railroads RU

urban and built-up -

cities, farmsteads, 

industry

UR

BARREN LAND (B)—<5% vegetative cover naturally or 

from construction.

culturally induced -

saline seeps, mines, 

quarries, and oil-waste 

areas

CI

other barren - salt flats, 

mudflats, slickspots, 

badlands

OB

permanent snow or ice PS rock RK

sand or gravel SG

CROP COVER (C)—includes entire cropping cycle (land 

prep, crop, or crop residue) for annual or perennial 

herbaceous plants.

close-grown crop -

wheat, rice, oats, and 

rye; small grains

CG

row crop - corn, cotton, 

soybeans, tomatoes, 

and other truck crops, 

tulips

RC

GRASS/HERBACEOUS COVER (G)—>50% grass, grasslike 

(sedges/rushes), or forb cover, mosses, lichens, ferns; 

nonwoody.

hayland - alfalfa, 

fescue, bromegrass, 

timothy

HL rangeland, savanna - 

10 to 20% tree cover RS

marshland - grasses 

and grasslike plants ML rangeland, shrubby -20 to 50% shrub cover RH
USDA-NRCS 1–17 September 2012

Kind 1 Code Kind 1 Code

pastureland, tame -

fescues, bromegrass, 

timothy, lespedeza

PL rangeland, tundra RT

rangeland, grassland; 

<10% trees, <20% 

shrubs; rangeland used 

for hayland

RG other grass and 

herbaceous cover OH

SHRUB COVER (S)—>50% shrub or vine canopy cover.

crop shrubs - filberts, 

blueberry, ornamental 

nusery stock

CS

native shrubs - shrub 

live oak, mesquite, 

sagebrush, creosote 

bush; rangeland >50% 

shrub cover

NS

crop vines - grapes, 

blackberries, raspberries CV other shrub cover OS

TREE COVER (T)—>25% canopy cover by woody plants, 

natural or planted.

conifers - spruce, pine, 

fir CO swamp - trees, shrubs SW

crop, trees - nuts, fruit, 

nursery, Christmas trees CR tropical - mangrove and royal palms TR

hardwoods - oak, 

hickory, elm, aspen HW other tree cover OC

intermixed hardwoods 

and conifers - oak-pine 

mix

IM

WATER (W)—water at the soil surface; includes seasonally 

frozen water.

1 Land Cover Kinds are presented at two levels of detail: Bolded 

table subheadings are the “NASIS - Level 1” choices (NSSH, 

Part 622.16; Soil Survey Staff, 2012d). Individual choices under 

the subheadings are the “NASIS - Level 2” choices.

VEGETATION

PLANT SYMBOL—Record the codes (scientific plant name 

abbreviations) for the major plant species found at the site (NRCS, 

2012); e.g., ANGE (Andropogon gerardii or big bluestem). (NOTE: 

The combination of plant symbol and common name are the 

primary plant data element in NASIS.)
USDA-NRCS 1–18 September 2012

PLANT COMMON NAME—Record the common names of the major 

plant species found at the site (NRCS, 2012); e.g., cottonwood, big 

bluestem. This item may be recorded as a secondary data element 

to augment the Plant Symbol. CAUTION: Multiple common names 

exist for some plants; not all common names for a given plant are 

in the national PLANTS database.

PLANT SCIENTIFIC NAME—Record the scientific plant name 

along with or in lieu of common names; e.g., Acer rubrum (red 

maple). (NOTE: Although used in the past, scientific names of 

plants [NRCS, 2012] are not presently recorded by the NRCS.) 

(NOTE: NASIS codes for common plant names are derived from the 

scientific names.)

VEGETATION COVER—Estimate the percent of the ground covered 

by each plant species recorded at the site.

PARENT MATERIAL

Describe the nature of the unconsolidated material (regolith) in 

which the soil is formed. If the soil is derived directly from the 

underlying bedrock (e.g., granite), identify the Parent Material as 

either grus, saprolite, or residuum and then record the appropriate 

Bedrock - Kind choice. (NOTE: NASIS uses “Component Parent 

Material Origin” to convey the source from which a Parent Material 

is derived, predominantly Bedrock - Kind.) Multiple parent 

materials, if present, should be denoted; e.g., loess, over colluvium, 

over residuum. Use numerical prefixes in the Horizon designations 

to denote different parent materials (lithologic discontinuities); e.g., 

A, BE, 2Bt, 2BC, 3C; Peoria Loess, or Calvert Formation.

KIND—e.g., saprolite, loess, colluvium.

Kind 1 Code Kind 1 Code

EOLIAN DEPOSITS (nonvolcanic)

eolian deposit EOD loess, calcareous CLO

eolian sands EOS loess, noncalcareous NLO

loess LOE parna PAR

GLACIAL and PERIGLACIAL DEPOSITS

cryoturbate CRY till, ablation ATI

drift GDR till, basal BTI

glaciofluvial deposit GFD till, flow FTI

glaciolacustrine deposit GLD till, lodgment LTI

glaciomarine deposit GMD till, melt-out MTI
USDA-NRCS 1–19 September 2012

Kind 1 Code Kind 1 Code

outwash OTW till, subglacial GTI

solifluction deposit SOD till, supraglacial UTI

supraglacial debris-flow SGF till, supraglacial 

meltout PTI

till TIL

IN-PLACE DEPOSITS (nontransported)

bauxite BAU residuum 2 RES

grus 2 GRU saprolite 2 SAP

MASS MOVEMENT DEPOSITS 3 (See Mass Movement Types 

table)

MISCELLANEOUS MASS MOVEMENT DEPOSITS

colluvium COL slump block SLB

scree SCR talus TAL

MASS MOVEMENT DEPOSIT (Unspecified Landslide) MMD

COMPLEX LANDSLIDE DEPOSITS CLD

FALL DEPOSITS FAD

debris fall deposit DLD soil fall deposit 

(=earth fall) SFD

rock fall deposit RFD

FLOW DEPOSITS FLD

earthflow deposit EFD debris avalanche 

deposit DAD

creep deposit CRP debris flow deposit DFD

mudflow deposit MFD debris slide deposit DSD

sand flow deposit SAD lahar LAH

solifluction deposit SOD rockfall avalanche 

deposit RAD

SLIDE DEPOSITS SD

debris slide deposit 4 OSD

Rotational Slide deposit RLD Translational Slide 

deposit TSD

rotational debris slide 

deposit RDD translational debris slide deposits TDD

rotational earth slide 

deposit RED translational earth slide deposit TED
USDA-NRCS 1–20 September 2012

Kind 1 Code Kind 1 Code

rotational rock slide 

deposit RRD translational rock slide deposit TRD

block glide deposit BGD

SPREAD DEPOSITS (=lateral spread) LSD

debris spread deposit DPD rock spread deposit RSD

earth spread deposit EPD

TOPPLE DEPOSITS TOD

debris topple deposit DTD rock topple deposit RTD

earth topple (=soil 

topple) ETD

MISCELLANEOUS DEPOSITS

diamicton DIM limonite LIM

gypsite GYP

ORGANIC DEPOSITS 5

coprogenic materials COM organic materials ORM

diatomaceous earth DIE organic, grassy 

materials OGM

marl MAR organic, herbaceous 

materials OHM

marl, coastal CMA organic, mossy 

materials OMM

marl, freshwater FWM organic, woody 

materials OWM

VOLCANIC DEPOSITS (unconsolidated; eolian and mass 

movement)

ash, volcanic (<2 mm) ASH cinders (2-64 mm) CIN

ash, acidic ASA

lahar deposit 

(volcaniclastic 

mudflow)

LAH

ash, andesitic ASN lapilli (2-64 mm, 

>2.0 sg) 6 LAP

ash, basaltic ASB pumice (<1.0 sg) 6 PUM

ash, basic ASC pyroclastic flow PYF

ash flow (pyroclastic) ASF pyroclastic surge PYS

bombs, volcanic (>64 

mm) BOM scoria (>2.0 sg) 6 SCO
USDA-NRCS 1–21 September 2012

Kind 1 Code Kind 1 Code

tephra (all ejecta) TEP

WATERLAID (or TRANSPORTED) DEPOSITS

alluvium ALL lagoonal deposits LGD

backswamp deposit BSD marine deposit MAD

beach sand BES marl MAR

coprogenic materials COM marl, coastal CMA

diatomaceous earth DIE marl, freshwater FWM

estuarine deposit ESD overbank deposit OBD

fluviomarine deposit FMD pedisediment PED

greensands GRS slope alluvium SAL

lacustrine deposit LAD valley side alluvium VSA

ANTHROPOGENIC DEPOSITS

coal extraction mine 

spoil CES metal ore extraction mine spoil MES

dredge spoils DGD mine spoil or earthy fill MSE

human-transported 

materials HTM

1 Parent material definitions are found in the “Glossary of Landform 

and Geologic Terms,” NSSH, Part 629 (Soil Survey Staff, 2012b), 

or the Glossary of Geology (Neuendorf et al., 2005).

2 Use the most precise term for the in situ material. Residuum is 

the most generic term.

3 Cruden and Varnes, 1996.

4 Debris slide is a more general, encompassing term that may be 

further subdivided into rotational debris slide or translational 

debris slide.

5 These generic terms refer to the dominant origin of the organic 

materials or deposits from which the organic soil has formed (i.e., 

parent material) (Soil Survey Division Staff, 1993). These terms 

partially overlap with those recognized in soil taxonomy (terms 

that refer primarily to what the organic material presently is); see 

the “Diagnostic Horizons or Characteristics” table.

6 sg=specific gravity=the ratio of a material’s density to that of 

water (weight in air/[weight in air - weight in water]).
USDA-NRCS 1–22 September 2012

BEDROCK

Describe the nature of the continuous hard rock underlying the soil. 

Specify the Kind, Fracture Interval, Hardness, and Weathering 

Class. 

KIND—e.g., limestone.

Kind 1 Code Kind 1 Code

IGNEOUS—INTRUSIVE

anorthosite ANO pyroxenite PYX

diabase DIA quartzite QZT

diorite DIO quartz-diorite QZD

gabbro GAB quartz-monzonite QZM

granite GRA syenite SYE

granitoid 2 GRT syenodiorite SYD

granodiorite GRD tonalite TON

monzonite MON ultramafic rock 2 UMU

peridotite PER

IGNEOUS—EXTRUSIVE

aa lava AAL pahoehoe lava PAH

andesite AND pillow lava PIL

basalt BAS pumice

(flow, coherent) PUM

block lava BLL rhyolite RHY

dacite DAC scoria (coherent mass) SCO

latite LAT tachylite TAC

obsidian OBS trachyte TRA

IGNEOUS—PYROCLASTIC

ignimbrite IGN tuff, welded TFW

pyroclastics 

(consolidated) PYR tuff breccia TBR

pyroclastic flow PYF volcanic breccia VBR

pyroclastic surge PYS volcanic breccia, acidic AVB

tuff TUF volcanic breccia, basic BVB

tuff, acidic ATU volcanic sandstone VST

tuff, basic BTU
USDA-NRCS 1–23 September 2012

Kind 1 Code Kind 1 Code

METAMORPHIC

amphibolite AMP metavolcanics MVO

gneiss GNE mica MIC

gneiss, biotite BTG mica schist MSH

gneiss, granodiorite GDG migmatite MIG

gneiss, hornblende HBG mylonite MYL

gneiss, migmatitic MMG phyllite PHY

gneiss, muscovite-biotite MBG schist SCH

granofels GRF schist, biotite BTS

granulite GRL schist, graphitic GRS

greenstone GRE schist, muscovite MVS

hornfels HOR schist, sericite SCS

marble MAR serpentinite SER

meta-conglomerate MCN siltite SIT

metaquartzite MQT slate SLA

metasedimentary rocks 2 MSR slate, sulfidic SFS

metasiltstone MSI soapstone (talc) SPS

SEDIMENTARY—CLASTICS

arenite ARE mudstone MUD

argillite ARG ortho-quartzite OQT

arkose ARK porcellanite POR

breccia, nonvolcanic 

(angular fragments) NBR sandstone SST

breccia, nonvolcanic, 

acidic ANB sandstone, calcareous CSS

breccia, nonvolcanic, 

basic BNB shale SHA

claystone CST shale, acid ASH

conglomerate (rounded 

fragments) CON shale, calcareous CSH

conglomerate, calcareous CCN shale, clayey YSH

fanglomerate FCN siltstone SIS

glauconitic sandstone GLS siltstone, calcareous CSI

graywacke GRY
USDA-NRCS 1–24 September 2012

Kind 1 Code Kind 1 Code

SEDIMENTARY—EVAPORITES, ORGANICS, AND 

PRECIPITATES

bauxite BAU limestone, coral COR

chalk CHA limestone, phosphatic PLS

lignite LIG limonite LIM

chert CHE novaculite NOV

coal COA rock anhydrite RAN

diatomite DIA rock gypsum GYP

dolomite (dolostone) DOL rock halite RHL

limestone LST travertine TRV

limestone, arenaceous ALS tripoli TRP

limestone, argillaceous RLS tufa TUA

limestone, cherty CLS

INTERBEDDED (alternating layers of different sedimentary 

lithologies)

limestone-sandstoneshale LSS sandstone-shale SSH

limestone-sandstone LSA sandstone-siltstone SSI

limestone-shale LSH shale-siltstone SHS

limestone-siltstone LSI

1 Definitions for kinds of bedrock are found in the “Glossary of 

Landform and Geologic Terms,” NSSH, Part 629 (Soil Survey 

Staff, 2012b), or in the Glossary of Geology (Neuendorf et al., 

2005).

2 Generic term; use only with regional or reconnaissance surveys 

(order 3, 4).

FRACTURE INTERVAL CLASS (called Bedrock_fracture_

interval in NASIS)—Describe the dominant (average) horizontal 

spacing between vertical joints (geogenic cracks or seams) in the 

bedrock layer.

Average Distance 

Between Fractures Code

 < 10 cm 1

10 to < 45 cm 2
USDA-NRCS 1–25 September 2012

Average Distance 

Between Fractures Code

45 to < 100 cm 3

100 to < 200 cm 4

≥ 200 cm 5

WEATHERING CLASS (called Bedrock_weathering in NASIS)—

The subjective extent to which bedrock has weathered as compared 

to its presumed nonweathered state. Record in Notes, if used.

Class Code

Slight SL

Moderate MO

Strong ST

DEPTH (TO BEDROCK)—Record the depth (cm) from the ground 

surface to the contact with coherent (continuous) bedrock.

LITHOSTRATIGRAPHIC UNIT(S)

Record the lithostratigraphic unit(s) of the unconsolidated material 

(regolith) and the bedrock in which the soil is formed or from which 

it is derived. (This is a text field in NASIS.) For example, Peoria 

Loess over pre-Illinoian till over Dakota Formation. (See discussion, 

p. 5–12.)

EROSION

Estimate the dominant kind and magnitude of accelerated erosion 

at the site. Specify the Kind and Degree.

KIND (called erosion_accelerated_kind in NASIS)—

Kind Code Criteria 1

wind I Deflation by wind

water: — Removal by running water

 sheet S Even soil loss, no channels

 rill R Small channels 2

 gully G Big channels 3

 tunnel T Subsurface voids within soil that enlarge by 

running water (i.e., piping)
USDA-NRCS 1–26 September 2012

1 Soil Survey Division Staff, 1993, p. 82.

2 Small runoff channels that can be obliterated by conventional 

tillage.

3 Large runoff channels that cannot be obliterated by conventional 

tillage.

DEGREE CLASS (called erosion_class in NASIS)—

Class 1 Code

Criteria: Estimated % loss of the original, 

combined A + E horizons or the estimated loss 

of the upper 20 cm (if original, combined A + E 

horizons were <20 cm thick). 2

None 0 0 %

1 1 > 0 up to 25%

2 2 25 up to 75%

3 3 75 up to 100%

4 4 > 75 % and total removal of A

1 In NASIS, the choices include the preceding word “Class” (e.g., 

Class 1).

2 Soil Survey Division Staff, 1993, pp. 86–89.

SURFACE FRAGMENTS

Record the amount of surface fragment cover (either as a class or 

as a numerical percent), as determined by either a “point count” 

or “line-intercept” method. In NASIS, additional details can be 

recorded: Surface Fragment Kind (called surface_frag_kind

in NASIS), Surface Fragment Class (relative quantity), Mean 

Distance Between Fragments (edge to edge), Shape (FL-flat 

or NF-nonflat), Size, Roundness (use classes and criteria found 

in “Rock Fragment – Roundness Table”), and Rock Fragment - 

Rupture Resistance.

KIND—Document the types of coarse fragments present (same 

options as “Rock & Other Fragments - Kind”).

Kind Code Kind Code

Includes all choices in Bedrock—Kind (except Interbedded), 

plus:

calcrete (caliche) 1 CA metamorphic rocks 2 MMR

carbonate concretions CAC mixed rocks 3 MXR
USDA-NRCS 1–27 September 2012

Kind Code Kind Code

carbonate nodules CAN ortstein fragments ORF

carbonate rocks 2 CAR petrocalcic fragments PEF

charcoal CH petroferric fragments TCF

cinders CI petrogypsic fragments PGF

durinodes DNN plinthite nodules PLN

duripan fragments DUF quartz QUA

foliated metamorphic 

rocks 2 FMR quartzite QZT

gibbsite concretions GBC scoria SCO

gibbsite nodules GBN sedimentary rocks 2 SED

igneous rocks 2 IGR shell fragments SHF

iron-manganese 

concretions FMC silica concretions SIC

iron-manganese nodules FMN volcanic bombs VB

ironstone nodules FSN volcanic rocks 2 VOL

lapilli LA wood WO

1 Fragments strongly cemented by carbonate; may include 

fragments derived from petrocalcic horizons.

2 Generic rock names may be appropriate for identifying fragments 

(e.g., a cobble) but are too general and should not be used to 

name Bedrock—Kind.

3 Numerous unspecified fragment lithologies are present, as in till 

or alluvium; not for use with residuum.

Surface Fragment 

Class 1

Code Criteria: percentage 

of surface covered Conv. 2 NASIS

Stony or Bouldery Class 1 % 0.01 to <0.1

Very Stony, or

Very Bouldery Class 2 % 0.1 to <3

Extremely Stony or

Extremely Bouldery Class 3 % 3 to <15

Rubbly Class 4 % 15 to <50

Very Rubbly Class 5 % ≥50 3
USDA-NRCS 1–28 September 2012

1 This is also used to record large wood fragments (e.g., tree 

trunks) on organic soils, if the fragments are a management 

concern and appear to be relatively permanent.

2 Historically called Surface Stoniness classes (now Surface 

Fragment classes). Use as a map unit phase modifier is restricted 

to stone-sized fragments or larger (>250 mm; Soil Survey Staff, 

1951).

3 If the percentage of surface fragments is >80%, the fragments 

are considered to be a distinct, separate horizon (NSSH, 

Amendment #4; 1998).

DIAGNOSTIC HORIZONS or CHARACTERISTICS

Identify the Kind and Upper and Lower Depths of occurrence of 

soil taxonomic diagnostic horizons and characteristics (Soil Survey 

Staff, 2010); e.g., mollic epipedon; 0-45 cm. Multiple features per 

horizon can be recorded. (Called Pedon Diagnostic Features in 

NASIS.) Record Kind, Thickness, Representative Value (RV). 

High Value and Low Value can also be recorded.

KIND—(see definitions in current Keys to Soil Taxonomy)

Kind Code Kind Code

EPIPEDONS (Diagnostic Surface Horizons)

anthropic AN mollic MO

folistic FO ochric OC

histic HI plaggen PL

melanic ME umbric UM

DIAGNOSTIC SUBSURFACE HORIZONS

agric AG natric NA

albic AL ortstein OR

argillic AR oxic OX

calcic CA petrocalcic PE

cambic CM petrogypsic PG

duripan DU placic PA

fragipan FR salic SA

glossic GL sombric SO

gypsic GY spodic SP

kandic KA sulfuric SU
USDA-NRCS 1–29 September 2012

Kind Code Kind Code

DIAGNOSTIC CHARACTERISTICS—MINERAL SOILS

abrupt textural change AC gypsum 

accumulations GA

albic materials AM lamella/lamellae LA

albic materials, 

interfingering of AI lithic contact 1 LC

andic soil properties AP lithologic discontinuity LD

anhydrous conditions AH paralithic contact 1 PC

aquic conditions 1 AQ paralithic materials 1 PM

artifacts ART permafrost 1 PF

cryoturbation 1 CR petroferric contact TC

densic contact 1 DC plinthite PI

densic materials 1 DM resistant minerals RM

durinodes DN slickensides SS

fragic soil properties FP spodic materials SPM

free carbonates FC sulfidic materials 1 SM

gelic materials 1 GM weatherable minerals WM

glacic layer 1 GL

DIAGNOSTIC CHARACTERISTICS—ORGANIC SOILS

(also see 1s above)

fibric soil materials FM limnic materials: LM

hemic soil materials HM coprogenous earth CO

humilluvic material UM diatomaceous earth DI

sapric soil materials RM marl MA

MISCELLANEOUS HORIZON FEATURES/CONDITIONS

anthric saturation 1 AS redox depletions with 

chroma 2 or less 1 RD

endosaturation 1 EN reduced matrix 1 RX

episaturation 1 ED salt accumulations ST

fibers FI secondary carbonates 

2 SC

n-value >0.7 NV strongly contrasting 

particle-size class SR

redox concentrations 1 RC volcanic glass VG
USDA-NRCS 1–30 September 2012

1 Diagnostic properties, materials, or conditions that can occur in 

either mineral or organic soils.

2 “Secondary carbonates” replaces “soft, powdery lime.” NOTE:

Gilgai is no longer a diagnostic feature in soil taxonomy.

DEPTH—Document the zone of occurrence for a diagnostic horizon 

or property, as observed, by recording the Top Depth and Bottom 

Depth and specifying units; e.g., 22-39 cm.

SOIL TAXONOMY CLASSIFICATION—After completely describing 

the soil, classify the pedon as thoroughly as possible (to the lowest 

level). See most recent version of Soil Taxonomy and Keys to Soil 

Taxonomy for complete choice lists; e.g., fine, mixed, active, mesic 

Typic Haplohumults.

PARTICLE-SIZE CONTROL SECTION—Record the Upper and 

Lower Depth of the zone used as the basis for identifying the 

particle-size control section; e.g., 30-80 cm (used to classify in soil 

taxonomy).

RESTRICTION

RESTRICTION - KIND—Identify any root-limiting/restrictive layers 

within the soil profile. Also record the Upper and Lower Depth of 

occurrence.

Kind Code Kind Code

abrupt textural change AC paralithic bedrock BPL

cemented horizon CH permafrost PF

densic material DM petrocalcic PE

densic bedrock BD petroferric TC

duripan DU petrogypsic PG

fragipan FR placic PA

human-manufactured 

materials HF plinthite PI

lithic bedrock BL salic SA

natric NA strongly contrasting 

textural stratification SR

ortstein OR sulfuric SU

RESTRICTION - HARDNESS—Estimate the hardness of a rootrestrictive layer. (Use Rupture Resistance - Cementation Classes.)
USDA-NRCS 1–31 September 2012

REFERENCES

Bureau of Chemistry and Soils. 1937. Soil survey manual. USDA 

Misc. Publ. 274. Washington, DC.

Cruden, D.M., and D.J. Varnes. 1996. Landslide types and 

processes. In A.K. Turner and R.L. Schuster (ed.) Landslides: 

Investigation and mitigation. Spec. Rep. 247, Transportation 

Research Board, National Research Council. National Academy 

Press, Washington, DC.

International Organization for Standards. 2012a (or current date). 

(http://www.iso.org/iso/country_codes/iso_3166_code_lists.htm) 

Note: Free versions at http://en.wikipedia.org/wiki/ISO_3166-1 for 

country codes.

International Organization for Standards. 2012b (or current date). 

(http://www.iso.org/iso/country_codes/iso_3166-2_database.htm) 

Note: Free versions at http://en.wikipedia.org/wiki/ISO_3166-1_

alpha-2 for administrative subdivisions within country.

National Institute of Standards and Technology. 1990. Counties 

and equivalent entities of the United States, its possessions and 

associated areas. U.S. Dep. Commerce, Federal Information 

Processing Standards Publ. (FIPS PUB 6–4).

Natural Resources Conservation Service. 2006. Land resource 

regions and major land resource areas of the United States, the 

Caribbean, and the Pacific Basin. USDA, Agric. Handb. 296. U.S. 

Gov. Print. Office, Washington, DC.

Natural Resources Conservation Service. 2012 (or most current 

date) [Online]. Complete PLANTS checklist. (The national PLANTS 

database.) USDA, National Plant Data Center, Baton Rouge, LA 

(http://plants.usda.gov).

Neuendorf, K., J.P. Mehl, and J.A. Jackson. 2005. Glossary of 

geology, 5th ed. Am. Geol. Inst., Alexandria, VA.

Public Building Service. Sept. 1996. Worldwide geographic location 

codes. U.S. Gen. Serv. Admin., Washington, DC.

Schoeneberger, P.J., D.A. Wysocki, E.C. Benham, and W.D. 

Broderson. 1998. Field book for describing and sampling soils (ver. 

1.1). USDA, NRCS, National Soil Survey Center, Lincoln, NE.

Schoeneberger, P.J., D.A. Wysocki, E.C. Benham, and W.D. 

Broderson (ed.) 2002. Field book for describing and sampling soils 

(ver. 2.0). USDA, NRCS, National Soil Survey Center, Lincoln, NE.

Soil Conservation Service. 1981. Land resource regions and major 

land resource areas of the United States. USDA, Agric. Handb. 296. 

U.S. Gov. Print. Office, Washington, DC.
USDA-NRCS 1–32 September 2012

Soil Survey Division Staff. 1993. Soil survey manual. USDA, SCS, 

Agric. Handb. 18. U.S. Gov. Print. Office, Washington, DC.

Soil Survey Staff. 1951. Soil survey manual. USDA, SCS, Agric. 

Handb. 18. U.S. Gov. Print. Office, Washington, DC.

Soil Survey Staff. 1962. Identification and nomenclature of soil 

horizons. Supplement to Agric. Handb. 18, Soil Survey Manual 

(replacing pages 173–188). USDA, SCS. U.S. Gov. Print. Office, 

Washington, DC.

Soil Survey Staff. 1983. National soil survey handbook, part 603, 

p. 45. USDA, SCS. U.S. Gov. Print. Office, Washington, DC.

Soil Survey Staff. 2010. Keys to soil taxonomy, 11th ed. USDA, 

NRCS. U.S. Gov. Print. Office, Washington, DC.

Soil Survey Staff. 2011. Soil survey laboratory information manual. 

Soil Surv. Invest. Rep. 45, ver. 2.0. USDA, NRCS, National Soil 

Survey Center, Lincoln, NE (ftp://ftp-fc.sc.egov.usda.gov/NSSC/

Lab_Info_Manual/SSIR_45.pdf).

Soil Survey Staff. 2012a. Data dictionary. In National soil 

information system (NASIS), release 6.2 [Online]. USDA, NRCS, 

National Soil Survey Center, Lincoln, NE.

Soil Survey Staff. 2012b. Glossary of landform and geologic terms. 

Part 629, National soil survey handbook (NSSH) [Online]. USDA, 

NRCS, National Soil Survey Center, Lincoln, NE.

Soil Survey Staff. 2012c. National soil information system (NASIS), 

release 6.2 [Online]. USDA, NRCS, Lincoln, NE.

Soil Survey Staff. 2012d. National soil survey handbook (NSSH) 

[Online]. USDA, NRCS, National Soil Survey Center, Lincoln, NE 

(http://soils.usda.gov/technical/handbook/).

Wysocki, D.A., P.J. Schoeneberger, D. Hirmas, and H.E. LaGarry. 

2012. Geomorphology of soil landscapes. In P.M. Huang et al. (ed.) 

Handbook of soil science: Properties and processes, 2nd ed. CRC 

Press, Taylor and Francis Group, LLC, Boca Raton, FL. ISBN: 978-1-

4398-0305-9.

Wysocki, D.A., P.J. Schoeneberger, and H.E. LaGarry. 2000. 

Geomorphology of soil landscapes. In M.E. Sumner (ed.) Handbook 

of soil science. CRC Press, LLC, Boca Raton, FL. ISBN: 0–8493–

3136–6.
USDA-NRCS 2–1 September 2012

PROFILE/PEDON DESCRIPTION

D.A. Wysocki, P.J. Schoeneberger, J.V. Chiaretti, and E.C. Benham, NRCS,

Lincoln, NE

OBSERVATION METHOD

For each layer, record the observation method by which the primary 

observations are made. (Common sampling devices are included 

in the “Soil Sampling” section.) Describe Kind and Relative Size; 

e.g., bucket auger, 3"; trench, 2 x 4 m.

KIND (called Observation_Method in NASIS)—

Kind 1 Code Criteria

“Disturbed” Samples

bucket auger BA Open, closed, sand, mud buckets (5-

12 cm diam.)

dutch or mud 

auger

DA

An open, strap-sided bucket (5-10 cm 

diam.) with a sharpened outer edge 

and a screw tip with a partial twist

screw auger SA External thread hand augers, power 

(flight) auger (2-30 cm diam.)

“Undisturbed” Samples

Macaulay 

sampler MC

A half-cylinder, “gouge” sampler with 

a hinged door that’s pushed in and 

partially rotated to obtain a sample of 

soft sediments (e.g., organics)

push tube PT Handheld or hydraulic, hollow stem 

(2-10 cm diam.)

shovel “slice” 2 SS Undisturbed block extracted with a 

shovel (sharpshooter: 20 x 40 cm)

vibracore tube VT A hollow tube (4-8 cm diam.) vibrated 

into wet sand, silt, or organics

WALL/FLOOR—“Undisturbed” Area or Exposure

small pit SP Hand or machine dug (<1 m x 2 m)

trench TR Hand or machine dug (>1 m x 2 m)

beveled cut BC Roadcuts graded to <60% slope

cut CU Roadcut, streambank, medium borrow 

pit wall >60% slope (>4 m, <33 m)

large open pit or 

quarry

LP Large borrow pit or quarry with large 

or irregular banks (>33 m)
USDA-NRCS 2–2 September 2012

Kind 1 Code Criteria

Other Observations

dive DV A visual onsite assessment performed 

underwater

video VO

Electronically recorded photo or 

sequential digital images of a 

subaqueous setting/site

1 Refer to Examples of Common Soil-Sampling Equipment

(p. 8–5) and Bucket Auger Types (p. 8–6) for examples of 

field equipment.

2 Field method used for hydric soil investigations.

RELATIVE SIZE (of exposure) (called Relative_Exposure_UOM

in NASIS)—Record the approximate size (scale) of the exposure 

observed. Use cm for “Drill Cores” and m for “Wall/Floor” 

observations; e.g., bucket auger, 3 cm; trench wall, 3 m. (NOTE:

Common size range for each method is indicated in the “Criteria” 

column of the “Observation Method – Kind” table. These dimensions 

are approximate; not intended to be precise.)

Relative Size of 

Exposure Observed Code Criteria

centimeters cm

meters m

HORIZON AND LAYER DESIGNATIONS

Use capital letters to identify master horizons; e.g., A, B. 

Use suffixes (lowercase letters) to denote additional horizon 

characteristics or features; e.g., Ap, Btk. (For more detailed criteria, 

see the “Soil Taxonomy” section [p. 4–1]; for complete definitions, 

see Keys to Soil Taxonomy [Soil Survey Staff, 2010].) Label a 

horizon (assign horizon designation) only after all morphology is 

recorded.

MASTER AND TRANSITIONAL HORIZONS AND LAYERS 1—

Identify the master horizons of the soil profile.

Horizon Criteria

(expanded details listed in “Soil Taxonomy” section)

O Organic soil materials (not limnic).

A Mineral; organic matter (humus) accumulation, loss 

of Fe, Al, clay.
USDA-NRCS 2–3 September 2012

Horizon Criteria

(expanded details listed in “Soil Taxonomy” section)

AB

or AE

or AC

Dominantly A horizon characteristics but also 

contains some B, E, or C horizon attributes.

A/B

or A/E

or A/C

Discrete, intermingled bodies of A and B, E, or C 

material; majority is A material.

E Mineral; some loss of Fe, Al, clay, or organic matter.

EA

or EB

or EC

Dominantly E horizon characteristics but also 

contains some A, B, or C horizon attributes.

E/A

or E/B

Discrete, intermingled bodies of E and A or B horizon 

material; majority of horizon is E material.

E and Bt

B and E

Thin, heavier textured lamellae (Bt) within a 

dominantly E horizon (or thin E within dominantly B 

horizon).

BA

or BE

or BC

Dominantly B characteristics but contains A, E, or C 

horizon attributes.

B/A

or B/E

or B/C

Discrete, intermingled bodies of B and A, E, or C 

material; majority of horizon is B material.

B

Subsurface accumulation of clay, Fe, Al, Si, humus, 

CaCO3, CaSO4; or loss of CaCO3; or accumulation of 

sesquioxides; or subsurface soil structure.

CB

or CA

Dominantly C horizon characteristics but also 

contains attributes of the B or A horizon.

C/B

or C/A

Discrete, intermingled bodies of C and B or A 

material; majority of horizon is C material.

C Little or no pedogenic alteration, unconsolidated 

earthy material, soft bedrock.

L Limnic soil materials.

W

A layer of liquid water (W) or permanently frozen 

water (Wf) within or beneath the soil (excludes 

water/ice above soil).

M Root-limiting subsoil layers of human-manufactured 

materials.

R Bedrock, strongly cemented to indurated.

1 See “Soil Taxonomy” (p. 4–6) for older horizon nomenclature.

2 Soil Survey Staff, 2010.
USDA-NRCS 2–4 September 2012

HORIZON SUFFIXES—Historically referred to as “Horizon 

Subscripts,” “Subordinate Distinctions,” 1 “Horizon_Designation_

Suffix” in NASIS, and as “Suffix Symbols” in soil taxonomy 2. 

(Historical designations and conversions are shown in the “Soil 

Taxonomy” section.)

Horizon 

Suffix

Criteria 2

(expanded details listed in “Soil Taxonomy” section)

a Highly decomposed organic matter (used only with O)

aa 3 (proposed) Accumulation of anhydrite (CaSO4)

b Buried genetic horizon (not used with C horizons)

c Concretions or nodules

co Coprogenous earth (used only with L)

d Densic layer (physically root restrictive)

di Diatomaceous earth (used only with L)

e Moderately decomposed organic matter (used only 

with O)

f Permanently frozen soil or ice (permafrost); 

continuous subsurface ice; not seasonal ice

ff Permanently frozen soil (“Dry” permafrost); no 

continuous ice; not seasonal ice

g Strong gley

h Illuvial organic matter accumulation

i Slightly decomposed organic matter (used only with O)

j Jarosite accumulation

jj Evidence of cryoturbation

k Pedogenic CaCO3 accumulation (<50% by vol.)

kk Major pedogenic CaCO3 accumulation (>50% by vol.)

m Continuous cementation (pedogenic)

ma Marl (used only with L)

n Pedogenic, exchangeable sodium accumulation

o Residual sesquioxide accumulation (pedogenic)

p Plow layer or other artificial disturbance

q Secondary (pedogenic) silica accumulation

r Weathered or soft bedrock

s Illuvial sesquioxide and organic matter accumulation

se Presence of sulfides (in mineral or organic horizons)

ss Slickensides
USDA-NRCS 2–5 September 2012

Horizon 

Suffix

Criteria 2

(expanded details listed in “Soil Taxonomy” section)

t Illuvial accumulation of silicate clay

u Presence of human-manufactured materials (artifacts)

v Plinthite

w Weak color or structure within B (used only with B)

x Fragipan characteristics

y Accumulation of gypsum

yy Dominance of gypsum (≈≥50% by vol.)

z Pedogenic accumulation of salt more soluble than 

gypsum

1 Soil Survey Division Staff, 1993.

2 Soil Survey Staff, 2010.

3 Personal communication with Soil Survey Standards Staff, 2012.

OTHER HORIZON MODIFIERS—

Numerical Prefixes (2, 3, etc.)—Used to denote lithologic 

discontinuities. By convention, 1 is understood but is not

shown; e.g., A, E, Bt1, 2Bt2, 2BC, 3C1, 3C2. (NOTE:

Discontinuities have important implications for site history, 

internal water flow, and soil interpretations [see additional 

discussion under “Subaqueous Soils,” p. 2–103]).

Numerical Suffixes—Used to denote subdivisions within a 

master horizon; e.g., A1, A2, E, Bt1, Bt2, Bt3, Bs1, Bs2.

The Prime ( ́) (Called horz_desgn_master_prime in 

NASIS)—Used to indicate the recurrence of identical horizon 

descriptor(s) in a profile or pedon; e.g., A, E, Bt, E ́ Btx, C. 

The prime does not indicate either buried horizons (which 

are denoted by a lowercase “b”; e.g., Btb) or lithologic 

discontinuities (denoted by numerical prefixes). In NASIS, up 

to five primes can be used to denote subsequent occurrences 

of horizon descriptors in a pedon; e.g., A, E, Bt, E ́, Btx, E ̋, 

Cd.

The Caret (^) symbol—Used as a prefix to master horizons 

to indicate human-transported material; e.g., ^A, ^Bw, 

C. (The caret symbol can be applied to all master horizon 

combinations except B and E, B/E, E and B, E/B, EC, L, M, R, 

or W.)
USDA-NRCS 2–6 September 2012

HORIZON DEPTH—Record the depths of both the upper and lower 

boundary for each horizon; specify units (centimeters preferred); 

e.g., 15-24 cm. Begin (zero datum) at the ground surface 1, which 

is not necessarily the mineral surface. (NOTE: Prior to 1993, 

the zero datum was at the top of the mineral surface, except for 

thick organic layers, such as peat or muck. Organic horizons were 

recorded as above and mineral horizons recorded as below, relative 

to the mineral surface.)

Example: Zero Datum for the same horizons 

At Present: Oe 0 - 5 cm, A 5 - 15 cm, E 15 - 24 cm

Before 1993: Oe 5 - 0 cm, A 0 - 10 cm, E 10 - 19 cm

1 Conventionally, the “soil surface” is considered to be the top 

boundary of the first layer that can support plant/root growth. 

This equates to:

a) (for bare mineral soil) the air/fine earth interface;

b) (for vegetated mineral soil) the upper boundary of the first 

layer that can support root growth;

c) (for organic mantles) the same as b) but excludes freshly 

fallen plant litter and includes litter that has compacted and 

begun to decompose; e.g., Oi horizon;

d) (for submerged soil) the same as b) but refers to the water/

soil contact and extends out from shore to the limit of 

emergent rooted plants;

e) (for rock mulches; e.g., desert pavement, scree) the same 

as a) unless the areal percentage of surface rock coverage is 

greater than 80%, the top of the soil is the mean height of 

the top of the rocks.

HORIZON THICKNESS—Record the average thickness and range 

in thickness of horizon; e.g., 15 cm (12-21 cm). NOTE: Used 

primarily for irregular soil horizons/layers.

HORIZON BOUNDARY—Record Distinctness and Topography

of horizon boundaries. (In NASIS, Distinctness is called Boundary 

Distinctness). Distinctness is the vertical distance through which the 

bottom of one horizon grades (transitions) into another. Topography 

is the lateral undulation and continuity of the boundary between 

horizons. A complete example is clear, wavy, or C,W.

Distinctness—The vertical distance (thickness) over which a 

horizon transitions to the top of the next.

Distinctness 

Class Code Criteria: transitional zone thickness

Very Abrupt V < 0.5 cm

Abrupt A 0.5 to < 2 cm
USDA-NRCS 2–7 September 2012

Distinctness 

Class Code Criteria: transitional zone thickness

Clear C 2 to < 5 cm

Gradual G 5 to < 15 cm

Diffuse D ≥ 15 cm

Topography—Cross-sectional shape of the contact between 

horizons.

Topography Code Criteria

Smooth S Planar with few or no irregularities

Wavy W Width of undulation is > than depth

Irregular I Depth of undulation is > than width

Broken B Discontinuous horizons; discrete but 

intermingled, or irregular pockets

A

B

Irregular

A

B

Wavy

A

B 

Smooth

Bt

B

A

E

Broken
USDA-NRCS 2–8 September 2012

SOIL COLOR

DECISION FLOWCHART FOR DESCRIBING SOIL COLORS—Use 

the following chart to decide how and with which data elements the 

color patterns of a soil or soil feature should be described.

Yes

Yes

Yes

No

No

No

Other

Colors

(nonmatrix colors)

Is the color associated with

a coat/stain, film,

concentration, or

depletion?

Is the feature

formed by oxidation

and reduction

processes?

Color

Is the color

a matrix color?

Redoximorphic Feature

(RMF)

Concentration, depletion, or

reduced matrix color

Nonredoximorphic

Feature

Concentration or Ped 

and Void Surface 

Feature; e.g., 

carbonate mass,

clay film, and organic

Mottle

lithochromic color;

e.g., 10YR 8/1

gibbsite; gray shales

Matrix Color

or

Mixed/ 

Intermingled

list in sequence,

dominant first

i.e., discrete, mixed,

or transitional horizons,

such as B/A

NOTE: Reduced matrix color is described as a matrix color and in 

the associated “(Soil Color) - Location or Condition Described Table.”
USDA-NRCS 2–9 September 2012

(SOIL) MATRIX COLOR—Record the Color(s), Moisture State, 

and Location or Condition.

(Soil) Matrix Color - (Soil) Color—Identify the soil matrix 

color(s) with Munsell® notation (Hue, Value, Chroma); e.g., 

10YR 3/2. For neutral colors, chroma is zero but not shown; 

e.g., N 4/. For other gley colors, use appropriate notation (see 

Munsell® gley pages; e.g., 5GY 6/1). For narrative descriptions 

(soil survey reports, Official Soil Series Descriptions), both the 

verbal name and the Munsell® notation are given; e.g., dark 

brown, 10YR 3/3.

(Soil) Matrix Color - Moisture State—Record the general 

moisture condition of the soil described; e.g., moist. (Not to be 

confused with Soil Water State.)

Moisture State Code

Dry D

Moist M

(Soil) Matrix Color - Location or Condition—Record 

pertinent circumstances of the color described (called color_

physical_state in NASIS) in Notes column.

Color Location or Condition Code

COLOR LOCATION

interior (within ped) IN

exterior (ped surface) EX

COLOR, MECHANICAL CONDITION

broken face BF

crushed CR

rubbed (used only with organic matter) RU

COLOR, REDOXIMORPHIC CONDITION

oxidized 1 OX

reduced 2 RE

COLOR, INTRICATE MULTICOLORED PATTERN

variegated 3 VA

1 Soil that is reduced in situ but has been extracted and exposed 

to the atmosphere (air) and has oxidized (changed color). A 

mineral example is vivianite. NOTE: Not used for soil that is 

normally oxidized in place. For indicators of reduction, see 

Redoximorphic Features.
USDA-NRCS 2–10 September 2012

2 Color determined immediately after extraction from a reduced 

environment and prior to oxidation; e.g., FeS. Also used to record 

Reduced Matrix.

3 Color pattern is too intricate (banded or patchy) with numerous 

diverse colors to credibly identify dominant matrix colors (e.g., 

foliated felsic crystalline saprolite).

REDOXIMORPHIC FEATURES—RMFs (DISCUSSION)

Redoximorphic features (RMFs) are color patterns in a soil caused 

by loss (depletion) or gain (concentration) of pigment compared 

to the matrix color, formed by oxidation/reduction of Fe and/or 

Mn coupled with their removal, translocation, or accrual; or a soil 

matrix color controlled by the presence of Fe+2. The composition 

and process of formation for a soil color or color pattern must be 

known or inferred before it can be described as an RMF. Because of 

this inference, RMFs are described separately from mottles, other 

concentrations (e.g., salts), or compositional features (e.g., clay 

films). RMFs generally occur in one or more of these settings:

a. In the soil matrix, unrelated to surfaces of peds or pores.

b. On or beneath the surfaces of peds.

c. As filled pores, as linings of pores, or beneath the surfaces of 

pores.

RMFs include the following:

1. Redox Concentrations—Localized zones of enhanced 

pigmentation due to an accrual of, or a phase change in, the 

Fe-Mn minerals; or physical accumulations of Fe-Mn minerals. 

NOTE: Iron concentrations may be either Fe+3 or Fe+2. Types of 

redox concentrations are:

a. Masses—Noncemented bodies of enhanced pigmentation that 

have a redder or blacker color than the adjacent matrix.

b. Nodules or Concretions—Cemented bodies of Fe-Mn oxides.

2. Redox Depletions—Localized zones of “decreased” 

pigmentation that are grayer, lighter, or less red than the 

adjacent matrix. Redox depletions include, but are not limited 

to, what were previously called “low-chroma mottles” (chroma 

≤2). Redox depletions of chroma ≤2 formed through reduction 

and oxidation processes are strong field indicators of saturation. 

Types of redox depletions are:

a. Iron Depletions—Localized zones that have one or more 

of the following: a yellower, greener, or bluer hue; a higher 

value; or a lower chroma than the matrix color. Color value is 
USDA-NRCS 2–11 September 2012

normally ≥4. Loss of pigmentation results from the loss of Fe 

and/or Mn. Clay content equals that in the matrix.

b. Clay Depletions—Localized zones that have either a yellower, 

greener, or bluer hue, a higher value, or a lower chroma 

than the matrix color. Color value is normally ≥4. Loss of 

pigmentation results from a loss of Fe and/or Mn and clay. Silt 

coats or skeletans commonly form as depletions but can be 

nonredox concentrations if deposited as flow material in pores 

or along faces of peds.

3. Reduced Matrix—A soil horizon that has an in situ matrix 

chroma ≤2 due to the presence of Fe+2. Color becomes redder or 

brighter (oxidizes) when the sample is exposed to air. The color 

change usually occurs within 30 minutes. A 0.2% solution of 

a,a’-dipyridyl dissolved in 1N ammonium acetate (NH4OAc) pH 7 

can verify the presence of Fe+2 in the field (Childs, 1981).

NOTE: RMF alters the traditional sequence for describing soil color 

(see the “Decision Flowchart for Describing Colors for Soil Matrix 

and Soil Features”). RMFs are described separately from other color 

variations or concentrations. Mottles (color variations not due to 

loss or accrual of Fe-Mn oxides; e.g., variegated weathered rock) 

are still described under Soil Color. A reduced matrix is recorded 

as an RMF and as “reduced” in Soil Color - Location or Condition 

Described.
USDA-NRCS 2–12 September 2012

REDOXIMORPHIC FEATURES

Record Kind, Quantity (percent of area covered), Size, Contrast, 

Color, Moisture State, Shape, Location, Hardness, and 

Boundary. A complete example is: common, medium, prominent, 

black iron-manganese nodules, moist, spherical, in the matrix, 

weakly cemented, sharp or c, 2, p, 5YR 2.5/1, FMM, M, S, MAT, 

w, s. At present, relict RMFs, as supported by geomorphic setting, 

water table data, etc., are recorded as ”relict RMFs” (include 

horizons and depths) under Miscellaneous Field Notes.

REDOXIMORPHIC FEATURES - KIND—

Kind Code Kind Code

REDUCED MATRIX (chroma ≤2 primarily from Fe+2)

reduced matrix RMX

REDOX DEPLETIONS (loss of pigment or material)

clay depletions CLD iron depletions FED

REDOX CONCENTRATIONS (accumulated pigment, 

material)

Masses 1 (noncemented)

iron (Fe+2) 2 F2M jarosite JAM

iron (Fe+3) 3, 4, 5 F3M manganese 4, 5 MNM

iron-manganese 3, 4, 5 FMM

Nodules 1 (cemented; no layers, crystals not visible at 10X)

ironstone FSN jarosite JAN

iron-manganese 4 FMN plinthite PLN

Concretions 1 (cemented; distinct layers, crystals not 

visible)

iron-manganese 4 FMC

Surface Coats/Films or Hypocoats

manganese (mangans: flat black, very thin, exterior 

films) MNF

ferriargillans (Fe+3 stained clay film) FEF

1 See discussion under Concentrations for definitions.

2 A concentration of reduced iron Fe+2; e.g., FeS.

3 A concentration of oxidized iron Fe+3; e.g., hematite (formerly 

described as reddish mottles).
USDA-NRCS 2–13 September 2012

4 Iron and Mn commonly occur in combination, and field 

identification of distinct phases is difficult. Use Mn masses

only for those that are at least Slightly Effervescent with H2O2. 

Describe nodules and concretions as iron-manganese unless 

colors are unambiguous.

5 Suggested color guidelines for field description of Fe vs. Mn 

masses:

Color of RMF or Concentration Dominant Composition

Value Chroma

≤2 ≤2 Mn

>2 and ≤4 >2 and ≤4 Fe and Mn

>4 >4 Fe

REDOXIMORPHIC FEATURES - QUANTITY (Percent of Area 

Covered)—See graphics for % of Area Covered (2, 20%) 

beginning on p. 7–1.

Class

Code Criteria: percent of 

Conv. NASIS surface area covered

Few f # < 2

Common c # 2 to < 20

Many m # ≥ 20

REDOXIMORPHIC FEATURES - SIZE—See size class graphic on 

next page.

Size Class Code Criteria

Fine 1 < 2 mm

Medium 2 2 to < 5 mm

Coarse 3 5 to < 20 mm

Very Coarse 4 20 to < 76 mm

Extremely Coarse 5 ≥ 76 mm
USDA-NRCS 2–14 September 2012
USDA-NRCS 2–15 September 2012

REDOXIMORPHIC FEATURES - CONTRAST—Record the color 

difference between the RMF and the dominant matrix color; e.g., 

Prominent or p. Use this table or the following chart to express the 

difference. (Also used for Concentrations and Mottles.)

Contrast 

Class

Code

Difference in Color Between Matrix and RMF

(∆ means “difference between”)

Faint 1 F

Hue (h) Value (v) Chroma (c)

∆h = 0; ∆v ≤ 2 and ∆c ≤ 1

∆h = 1; ∆v ≤ 1 and ∆c ≤ 1

∆h = 2; ∆v = 0 and ∆c = 0

Distinct 1 D

∆h = 0; ∆v ≤ 2 and ∆c > 1 to < 4

or ∆v > 2 to < 4 and ∆c < 4

∆h = 1; ∆v ≤1 and ∆c > 1 to < 3

or ∆v > 1 to < 3 and ∆c < 3

∆h = 2; ∆v = 0 and ∆c > 0 to < 2

or ∆v > 0 to < 2 and ∆c < 2

Prominent 1 P ∆h = 0; ∆v ≥ 4 or ∆c ≥ 4

∆h = 1; ∆v ≥ 3 or ∆c ≥ 3

∆h = 2; ∆v ≥ 2 or ∆c ≥ 2

∆h ≥ 3;

1 If compared colors have both a value ≤3 and a chroma of ≤2, the 

contrast is Faint, regardless of hue differences.
USDA-NRCS 2–16 September 2012 Hues are the same (∆ h = 0) 1 ∆ Value ∆ Chroma Contrast 0 ≤1 Faint 0 2 Distinct 0 3 Distinct 0 ≥4 Prominent 1 ≤1 Faint 1 2 Distinct 1 3 Distinct 1 ≥4 Prominent ≤2 ≤1 Faint ≤2 2 Distinct ≤2 3 Distinct ≤2 ≥4 Prominent 3 ≤1 Distinct 3 2 Distinct 3 3 Distinct 3 ≥4 Prominent ≥4 — Prominent Hues differ by 1 (∆ h = 1) 1 ∆ Value ∆ Chroma Contrast 0 ≤1 Faint 0 2 Distinct 0 ≥3 Prominent 1 ≤1 Faint 1 2 Distinct 1 ≥3 Prominent 2 ≤1 Distinct 2 2 Distinct 2 ≥3 Prominent ≥3 — Prominent Hues differ by 2 (∆ h = 2) 1 ∆ Value ∆ Chroma Contrast 0 0 Faint 0 1 Distinct 0 ≥2 Prominent 1 ≤1 Distinct 1 ≥2 Prominent ≥2 — Prominent Hues differ by 3 or more (∆ h ≥ 3) 1 ∆ Value ∆ Chroma Contrast Color contrast is Prominent, except for low chroma and value 1 Prominent 1 Exception: If both colors have a value ≤3 and a chroma ≤2, the color contrast is Faint, regardless of hue differences. Tabular List for Determination of Color Contrast
USDA-NRCS 2–17 September 2012

REDOXIMORPHIC FEATURES - COLOR—Use standard Munsell® 

notation from the “Soil Color” section; e.g., light brownish gray or 

2.5Y 6/2.

REDOXIMORPHIC FEATURES - MOISTURE STATE—Describe the 

moisture condition of the redoximorphic feature (use “Soil Color - 

Moisture State” table); e.g., Moist (M).

Moisture State Code

Dry D

Moist M

REDOXIMORPHIC FEATURES - SHAPE—Describe the shape of 

the redoximorphic feature (use “Concentrations - Shape” table); 

e.g., Spherical (S).

REDOXIMORPHIC FEATURES - LOCATION—Describe the 

location(s) of the redoximorphic feature within the horizon (use 

“Concentrations – Location” table); e.g., In the matrix around 

depletions (MAD).

REDOXIMORPHIC FEATURES - HARDNESS—Describe the 

relative force required to crush the redoximorphic feature (use the 

same classes and criteria as the “Rupture Resistance for Blocks/

Peds/Clods-Cementation” column); e.g., Strongly Cemented (ST).

REDOXIMORPHIC FEATURES - BOUNDARY—The gradation 

between the redoximorphic feature and the adjacent matrix (use 

“Concentrations - Boundary” table; p. 2–27); e.g., Sharp (S).
USDA-NRCS 2–18 September 2012

MOTTLES

Describe mottles (areas that differ from the matrix color). Mottles 

commonly have a lithomorphic or lithochromic (e.g., gray shale) 

geologic origin rather than pedogenic. Mottles do not indicate 

existing redox conditions. Describe Redoximorphic Features and Ped 

and Void Surface Features (e.g., clay films) separately from mottles. 

Record Quantity Class (in NASIS, estimate “Percent of Horizon 

Area Covered”), Size, Contrast, Color, and Moisture State (D 

or M). Shape is an optional descriptor. A complete example is: 

common (15%), medium, distinct, reddish yellow, moist, irregular 

mottles; or c, 2, d, 7.5YR 7/8, M, I mottles.

MOTTLE QUANTITY (Percent of Area Covered)—See graphics 

for % of Area Covered (2, 20%), p. 7–1 to p. 7–9.

Quantity 

Class

Code

Criteria: range in percent Conv. NASIS

Few f % <2% of surface area

Common c % 2 to <20% of surface area

Many m % ≥20% of surface area

MOTTLE SIZE—Size refers to dimensions as seen on a plane. If 

mottle length is <3 times the mottle width, record the greater of 

the two. If length is >3 times width, record the smaller dimension. 

(See graphic on p. 2–14.)

Size Class Code Criteria

Fine 1 0.25 to < 2 mm

Medium 2 2 to < 5 mm

Coarse 3 5 to < 20 mm

Very Coarse 4 20 to < 76 mm

Extremely Coarse 5 ≥ 76 mm

MOTTLE CONTRAST—Use Redoximorphic Feature - Contrast

criteria and table (p. 2–15).

MOTTLE COLOR—Use standard Munsell® notation of hue, value, 

and chroma; e.g., 5YR 4/4 (for reddish brown).

MOTTLE MOISTURE STATE—Record moisture condition of mottle 

(don’t confuse with soil water state); e.g., moist (M) or dry (D).

MOTTLE SHAPE (optional)—Use “Concentrations - Shape” table; 

e.g., irregular.

MOTTLE LOCATION (optional)—Use (Soil) Matrix Color - 

Location or Condition table; e.g., interior.
USDA-NRCS 2–19 September 2012

CONCENTRATIONS (DISCUSSION)

Concentrations are soil features that form by accumulation of 

material during pedogenesis. Dominant processes involved are 

chemical dissolution/precipitation; oxidation and reduction; and 

physical and/or biological removal, transport, and accrual. Types 

of concentrations (modified from Soil Survey Division Staff, 1993) 

include the following:

1. Finely Disseminated Materials are physically small 

precipitates (e.g., salts, carbonates) dispersed throughout 

the matrix of a horizon. The materials cannot be readily seen 

(10X lens) but can be detected by a chemical reaction (e.g., 

effervescence of CaCO3 by HCl) or other proxy indicators.

2. Masses are noncemented (“Rupture Resistance-Cementation 

Class” of Extremely Weakly Cemented or less) bodies of 

accumulation of various shapes that cannot be removed as 

discrete units and do not have a crystal structure that is readily 

discernible in the field (10X hand lens). This includes finely 

crystalline salts and Redox Concentrations that do not qualify as 

nodules or concretions.

3. Nodules are cemented (Very Weakly Cemented or greater) 

bodies of various shapes (commonly spherical or tubular) that 

can be removed as discrete units from soil and don’t slake. 

Crystal structure is not discernible with a 10X hand lens.

4. Concretions are cemented bodies (Very Weakly Cemented or 

greater) that don’t slake and are similar to nodules, except for 

the presence of visible concentric layers of material around a 

point, line, or plane. The terms “nodule” and “concretion” are not 

interchangeable.

5. Crystals are macro-crystalline forms of relatively soluble 

salts (e.g., halite, gypsum, carbonates) that form in situ by 

precipitation from soil solution. The crystalline shape and 

structure are readily discernible in the field with a 10X hand lens.

6. Biological Concentrations are discrete bodies accumulated by 

a biological process (e.g., fecal pellets) or pseudomorphs of biota 

or biological processes (e.g., insect casts) formed or deposited in 

soil.

7. Inherited Minerals are field-observable particles (e.g., mica 

flakes) or aggregates (e.g., glauconite pellets) that impart 

distinctive soil characteristics and formed by geologic processes 

in the original parent material and subsequently inherited 

by the soil rather than formed or concentrated by pedogenic 

processes. Included here due to historical conventions; not all 

concentrations descriptors may apply (e.g., shape, color).
USDA-NRCS 2–20 September 2012

General conventions for documenting various types of 

concentrations:

Type of Distribution Documentation Examples

Finely Disseminated 

(discrete bodies not 

visible)

Horizon Suffix, 

Concentrations 

(finely disseminated)

Carbonates (none)

Salts (Bz, Bn)

Masses, Nodules, 

Concretions, Crystals, 

Biological Features

Redoximorphic 

Features, or 

Concentrations

Mn nodules

Fe concretions

Insect casts

Continuous 

Cementation

Terms in Lieu of 

Texture

Duripan

Petrocalcic

CONCENTRATIONS

Record Kind, Quantity (percent of area covered), Size, Contrast, 

Color, Moisture State, Shape, Location, Hardness, and 

Boundary. A complete example is: many, fine, prominent, white, 

moist, cylindrical, carbonate nodules in the matrix, moderately 

cemented, clear, or m, 1, p, 10YR 8/1, M, c, CAN, MAT, M, c.

CONCENTRATIONS - KIND—Identify the composition and 

the physical state of the concentration in the soil. NOTE: Table 

subheadings (e.g., Masses) are a guide to various physical states of 

materials. Materials with similar or identical chemical composition 

may occur in multiple physical states (under several subheadings); 

e.g., salt masses and salt crystals.
USDA-NRCS 2–21 September 2012

CONCENTRATIONS (NONREDOX) (accumulations of material)

Kind Code Kind Code

FINELY DISSEMINATED (bodies not visible by unaided eye; 

detectable by chemical tests, e.g., Effervescence)

finely disseminated 

carbonates FDC finely disseminated salts FDS

finely disseminated 

gypsum

FDG

MASSES (noncemented; crystals not visible with 10X hand lens)

barite masses (BaSO4 ) BAM

gypsum masses

(CaSO4 • 2H2O) 

crystals not visible

GYM

carbonate masses

(Ca, Mg, NaCO3 ) CAM salt masses(NaCl, Na-Mg sulfates) SAM

clay bodies CBM silica masses SIM

gypsum crystal clusters 

(nests) very fine crystals GNM

NODULES (cemented; noncrystalline at 10X, no layers)

carbonate nodules 1 CAN opal OPN

durinodes (SiO2 ) DNN ortstein nodules ORT

gibbsite nodules (Al2O3 ) GBN

CONCRETIONS (cemented; noncrystalline at 10X, distinct 

layers)

carbonate concretions 1 CAC silica concretions SIC

gibbsite concretions GBC titanium oxide 

concretions TIC

CRYSTALS (crystals visible with 10X hand lens or larger)

barite crystals (BaSO4 ) BAX salt crystals

(NaCl, Na-Mg sulfates) SAX

calcite crystals (CaCO3 ) CAX satin spar crystals

(CaSO4 • 2H2O) SSC

gypsum crystals

(unspecified; CaSO4 • 

2H20)

GYX selenite crystals

(CaSO4 • 2H2O) SEC
USDA-NRCS 2–22 September 2012

CONCENTRATIONS (NONREDOX) (accumulations of material)

Kind Code Kind Code

BIOLOGICAL CONCENTRATIONS (entities, byproducts, or 

pseudomorphs)

diatoms 2 DIB root sheaths RSB

fecal pellets FPB shell fragments 

(terrestrial or aquatic) SFB

insect casts 3

(e.g., cicada mold) ICB sponge spicules 2 SSB

plant phytoliths 2

(plant opal) PPB worm casts 3 WCB

INHERITED MINERALS (geogenic) 4

glauconite pellets GLI volcanic glass VOG

mica flakes MIC

MISCELLANEOUS 5

carbonate bands CBA carbonate ooliths CAO

carbonate beds CBE carbonate pisoliths CAP

carbonate laminae CAL carbonate root casts CRC

1 For example: loess doll (aka “loess kindchen,” “loess puppies,”

etc.).

2 Commonly requires magnification >10X to be observed.

3 Worm casts are ovoid, fecal pellets excreted by earthworms. 

Insect casts are cemented (e.g., CaCO3) molds of insect bodies or 

burrows.

4 Minerals inherited from parent material rather than formed in soil.

5 See Discussion on carbonate stages (p. 2–28).
USDA-NRCS 2–23 September 2012

CONCENTRATIONS - QUANTITY (PERCENT OF AREA 

COVERED)—See graphics for % of Area Covered (2, 20%) 

beginning on p. 7–1.

Class

Code Criteria: percent of 

Conv. NASIS surface area covered

Few f # < 2

Common c # 2 to < 20

Many m # ≥ 20

CONCENTRATIONS - SIZE (Same as “RMFs” and “Mottle Size 

Classes”)—See graphic on page p. 2–24.)

Size Class Code Criteria

Fine 1 0.25 to < 2 mm

Medium 2 2 to < 5 mm

Coarse 3 5 to < 20 mm

Very Coarse 4 20 to < 76 mm

Extremely Coarse 5 ≥ 76 mm

CONCENTRATIONS - CONTRAST—Use “RMF - Contrast” table or 

chart; e.g., distinct.

CONCENTRATIONS - COLOR—Use standard Munsell® notation; 

e.g., 7.5YR 8/1.

CONCENTRATIONS - MOISTURE STATE—Use “Soil Color – 

Moisture State” table; i.e., Moist (M) or Dry (D).
USDA-NRCS 2–24 September 2012
USDA-NRCS 2–25 September 2012

CONCENTRATIONS - SHAPE 1 (also used for Mottles, 

Redoximorphic Features)

Shape 1 Code Criteria

cubic CU crudely equidimensional blocklike units

cylindrical C tubular and elongated bodies; e.g., filled 

wormholes and insect burrows

dendritic D tubular, elongated, and branched bodies; 

e.g., pipestems (root pseudomorphs)

irregular I bodies of nonrepeating spacing or shape

lenticular L

disk-shaped forms with thicker centers and 

thinning towards outer edge (e.g., doubleconvex lens)

pendular PE

irregular drapes, coatings, or nodules 

suspended from underside of coarse 

fragments (e.g., pendular gypsum masses)

platy P relatively thin, tabular sheets, lenses; e.g., 

lamellae

reticulate R crudely interlocking bodies with similar 

spacing; e.g., plinthite

rosettelike RO

interlocking blades radiating out from a 

central point forming petal-like clusters; 

e.g., barite

spherical S well-rounded to crudely spherical bodies; 

e.g., Fe/Mn “shot”

threadlike T

thin (e.g., <1 mm diam.) elongated 

filaments; generally not dendritic (e.g., very 

fine CaCO3 stringers)

1 Shape terms are presented as adjectives due to the typical data 

string output (e.g., dendritic carbonate concretions).
USDA-NRCS 2–26 September 2012

Examples of Mottles,

Concentrations, and

RMF Shapes

platy

(e.g.,

lamellae) 

spherical

(e.g., Fe/Mn

shot)

threadlike

(e.g., very fine

CaCO stringers

and filaments)

3

cubic

(e.g., halite) 

pendular

(e.g., CaCO ,

CaSO , SiO ) 

3

4 4

lenticular

(e.g., gypsum) 

dendritic

(e.g., branched

root pseudomorphs) 

reticulate

(e.g., plinthite)

rosettelike

(e.g., barite,

gypsum) 

irregular

cylindrical

(e.g., filled

worm holes)

CONCENTRATIONS - LOCATION—Describe the location(s) of the 

concentration (or depletion for RMFs) within the horizon. Historically 

called Concentrations - Distribution.

Location Code

MATRIX (in soil matrix; not associated with ped faces or 

pores)

In the matrix (not associated with peds/pores) MAT

In matrix surrounding redox depletions MAD

In matrix surrounding redox concentrations MAC

Throughout (e.g., finely disseminated carbonates) TOT

PEDS (on or associated with faces of peds)

Between peds BPF

Infused into the matrix along faces of peds (hypocoats) MPF

On faces of peds (all orientations) APF

On horizontal faces of peds HPF

On vertical faces of peds VPF
USDA-NRCS 2–27 September 2012

Location Code

PORES (in pores or associated with surfaces along pores)

Infused into the matrix adjacent to pores (hypocoats; 

see graphic p. 2–34) MPO

Lining pores (see graphic p. 2–34) LPO

On surfaces along pores SPO

On surfaces along root channels RPO

OTHER

In cracks CRK

At top of horizon TOH

Around rock fragments ARF

On bottom of rock fragments (e.g., pendants) BRF

On slickensides SSS

Along lamina or strata surfaces ALS

CONCENTRATIONS - HARDNESS—Describe the relative force 

required to crush the concentration body (use the same criteria and 

classes as in the “Rupture Resistance for Blocks, Peds, and 

Clods – Cementation” column (exclude the Noncemented class); 

e.g., Moderately Cemented. 

CONCENTRATIONS - BOUNDARY—The gradation between feature 

and matrix. (Also used to describe Redoximorphic Features - 

Boundary.)

Class Code Criteria

Sharp S Color changes in <0.1 mm between the feature 

and the soil matrix; change is abrupt even 

under a 10X hand lens.

Clear C Color changes within 0.1 to <2 mm between 

the feature and the soil matrix; gradation is 

visible without 10X lens.

Diffuse D Color changes in ≥2 mm between the feature 

and the soil matrix; gradation is easily visible 

without 10X hand lens.
USDA-NRCS 2–28 September 2012

PEDOGENIC CARBONATE STAGES (DISCUSSION)

Pedogenic Carbonate Development: In arid, semiarid, and 

subhumid environments, pedogenic carbonate accumulation is of 

overarching and unifying importance. The present morphological 

concepts and intellectual basis for soil-carbonate horizons and 

stages that follow originate from the seminal contributions of Leland 

Gile (Gile, 1961, 1970, 1975, 1993; Gile and Grossman, 1968; Gile 

and Grossman, 1979; Gile et al., 1966; Gile et al., 2007).

Calcium carbonate (CaCO3) mediates or controls key chemical and 

physical soil properties (e.g., pH, nutrient availability, dispersionflocculation, organic matter stabilization). Calcium carbonate in 

soil may be inherited from parent material and/or may accumulate 

via pedogenic processes. Climate (precipitation, temperature, 

evapotranspiration), carbonate solubility, and microbial 

biomineralization control and constrain the rate and quantity of 

pedogenic carbonate accumulation. Major carbonate accumulation 

occurs mainly in subhumid to arid regions (precipitation ~<750mm/

annum). Pedogenic carbonate formation requires a Ca source, 

such as mineral weathering, concentration by soil or ground 

water evaporation, and/or input via dust and/or precipitation. The 

carbonate (CO3

-2) source is plant and microbial respiration (CO2) via 

the CO2-HCO3

-1-CO3-2 equilibria. Beyond the major climatic control, 

pedogenic carbonate accumulation depends on a balance among 

geomorphic age or landscape stability, soil water movement (at 

both profile and landscape scales), soil texture, and vegetation type 

and quantity. 

Pedogenic carbonate accumulation follows a morphogenetic 

development sequence starting as horizon features, such as 

carbonate coatings, masses, and fine nodules. If carbonate 

continues to accumulate, it may entirely engulf, plug, and cement 

soil horizons. Carbonate-cemented soil horizons are generically 

termed caliche or calcrete and are recognized in Soil Taxonomy as 

petrocalcic horizons. Pedogenic carbonate accumulation is closely 

linked to soil age (Gile et al., 1981; Machette, 1985). Soils on 

progressively older geomorphic surfaces contain sequentially more 

pedogenic carbonate. The progression of carbonate development 

and morphology has been defined as Stages I through VI (see 

figures A and B) (Gile et al., 1966; Gile et al., 1981; Brock, 2007; 

Machete, 1985; Bachman and Machette, 1977).

Pedogenic carbonate stage morphology and expression are initially 

different for a fine earth matrix (fig. A; e.g., lacustrine, distal 

fan deposits, eolian deposits) than for a coarse fragment matrix 

(fig. B; e.g., proximal alluvial fan deposits, channel deposits) soils 

(Gile et al., 1966; Flach et al., 1969; Gile et al., 1981). The time 

required for carbonate stage development depends on soil texture 

and its control on porosity. A fine-grained soil has greater surface 

area and total porosity that requires a correspondingly greater 
USDA-NRCS 2–29 September 2012

carbonate quantity to fill voids and form equivalent carbonate 

stages compared to a coarse-textured soil (Gile, 1993; Gile et al., 

1981). Thus, it takes more time for a fine-grained soil to reach the 

same carbonate stage as a coarse-textured soil under the same 

conditions.

Multiple Carbonate Stages: Pedogenic carbonates (especially 

Stages IV through VI) are durable and persistent in arid 

environments. If different sedimentation events and subsequent 

pedogenesis (separated by time) occur to produce a stacked soil 

sequence (paleosols), a pedon may contain multiple carbonate 

stages. Each soil sequence (sediment package) is evaluated 

independently, and a carbonate stage is attached to horizons in 

that sequence. For example, Stage II carbonate may occur in 

a soil overlying a buried soil with Stage IV carbonate; e.g., A, 

0-12 cm; Bt, 12‐22 cm; Bk (Stage II CaCO3 nodules), 22-65cm; 

2Bkkm1 (Stage IV CaCO3), 65-150 cm; 2Bkkm2 (Stage IV CaCO3), 

150-260 cm. Moreover, on stable geomorphic surfaces climatic 

shifts may superpose younger carbonate forms into preexisting, 

more advanced stages within the same soil. For example, 

carbonate nodules may occur above and into a stage IV Bkkm; 

e.g., A, 0-11 cm; Bt, 11-22 cm; Bk (CaCO3 nodules), 22-65 cm; 

Bkkm (Stage IV CaCO3), 65-150 cm; 2Bkkm (Stage IV CaCO3), 

150-260 cm. Despite the more recent nodules, this soil is Stage IV

in the morphogenetic sequence.

Pedogenic Carbonate Stage Description: Evaluate and record 

the Pedogenic Carbonate Stage by pedon. More than one CaCO3

stage may exist in a pedon as a result of multiple sediment 

layers or shifting climate conditions (see discussion). Pedogenic 

carbonates are described under both Concentrations and Ped and 

Void Surface Features. In arid and semiarid regions, a pedogenic 

carbonate stage is commonly based upon the overall carbonate 

morphology in relation to texture and coarse fragment content (see 

figures A and B). The “stage” is recorded as an interpretive text 

note following the conventional carbonate concentration description; 

e.g., 100-165 cm, 2Bkkm (massive indurated CaCO3), Stage IV. 

Assigning a CaCO3 stage is an interpretive complement to, but not a 

replacement for, conventional soil horizonation.
USDA-NRCS 2–30 September 2012
USDA-NRCS 2–31 September 2012
USDA-NRCS 2–32 September 2012

PED and VOID SURFACE FEATURES

These features are coats/films, hypocoats, or stress features formed 

by translocation and deposition or by shrink-swell processes on or 

along surfaces. Describe Kind, Amount Class (percent in NASIS), 

Distinctness, Location, and Color (dry or moist). An example is: 

many, faint, brown 10YR 4/6 (Moist) clay films on all faces of peds 

or m, f, 10YR 4/6 (M), CLF, PF.

PED and VOID SURFACE FEATURES - KIND (nonredoximorphic)

Kind Code Field Criteria

COATS, FILMS (exterior, adhered to surface)

carbonate coats CAF off-white, effervescent with HCl

silica (silans, opal) SIF off-white, noneffervesent with HCl

clay films (argillans) CLF waxy, exterior coats

clay bridges BRF “wax” between sand grains

ferriargillans

described as RMFKind

see 

RMFs Fe+3 stained clay film

gibbsite coats 

(sesquan) GBF AlOH3, off-white, noneffervescent with HCl

gypsum coats GYF CaSO4 • 2H2O

manganese 

(mangans)

described as RMFKind

see 

RMFs

black, thin films effervescent with 

H2O2

organic stains OSF dark organic films

organoargillans OAF dark, organic stained clay films

sand coats SNF separate grains visible with 10X

silt coats 1 SLF separate grains not visible at 10X

skeletans 2 (sand 

or silt) SKF clean sand or silt grains as coats

HYPOCOATS 3 (a stain infused beneath a surface)

STRESS FEATURES (a smeared exterior face)

pressure faces (i.e., 

stress cutans) PRF look like clay films; sand grains uncoated
USDA-NRCS 2–33 September 2012

Kind Code Field Criteria

slickensides 

(pedogenic) SS

shrink-swell shear features (e.g., 

grooves, striations, glossy surface) 

on pedo-structure surfaces (e.g., 

wedges, bowls); can be horizontal

slickensides 

(geogenic) SSG

vertical/oblique, roughly planar 

shear face from external stress 

(e.g., faults; mass movement); 

striations, grooves

1 Individual silt grains are not discernible with a 10X lens. Silt coats 

occur as a fine, off-white, noneffervescent, “grainy” coat on ped 

surfaces.

2 Skeletans are (pigment) stripped grains >2 μm and <2 mm 

(Brewer, 1976). Preferably describe either silt coats (grains not 

discernible with 10X lens) or sand coats (grains discernible with 

10X lens).

3 Hypocoats, as used here, are field-scale features commonly 

expressed only as redoximorphic features. Micromorphological 

hypocoats include nonredoximorphic features (Bullock et al., 

1985).
USDA-NRCS 2–34 September 2012
USDA-NRCS 2–35 September 2012

PED and VOID SURFACE FEATURES - AMOUNT—Estimate 

the relative percent of the visible surface area that a ped surface 

feature occupies in a horizon. (See graphics for % of Area 

Covered [5, 25, 50, 90%] beginning on page 7.1.) In NASIS, 

record the estimate as a numeric percent; e.g., 20%.

Amount 

Class

Code Criteria: percent of surface 

Conv. NASIS area

Very Few vf % < 5 percent

Few f % 5 to < 25 percent

Common c % 25 to < 50 percent

Many m % 50 to < 90 percent

Very Many vm % ≥ 90 percent

PED and VOID SURFACE FEATURES - CONTINUITY (Obsolete in 

NRCS; replaced with Ped and Void Surface Features - Amount

in NASIS.)

Continuity Class Conv. Code Criteria: features occur as

Continuous C Entire Surface Cover

Discontinuous D Partial Surface Cover

Patchy P Isolated Surface Cover

PED and VOID SURFACE FEATURES - DISTINCTNESS—The 

relative extent to which a ped surface feature visually stands out 

from adjacent material.

Distinctness 

Class

Code Criteria:

Faint F Visible only with magnification (10X hand 

lens); little contrast between materials.

Distinct D Visible without magnification; significant 

contrast between materials.

Prominent P Markedly visible without magnification; 

sharp visual contrast between materials.

OBSOLETE
USDA-NRCS 2–36 September 2012

PED and VOID SURFACE FEATURES - LOCATION—Specify 

where ped surface features occur within a horizon; e.g., Between 

sand grains.

Location Code

PEDS

On all faces of peds (vertical and 

horizontal) PF

On bottom faces of peds BF

On top faces of peds TF

On tops of soil columns TC

On vertical faces of peds VF

OTHER (NONPED)

Between sand grains (bridging) BG

On bedrock BK

On bottom surfaces of rock fragments BR

On concretions CC

On nodules NO

On rock fragments RF

On slickensides SS

On surfaces along pores SP

On surfaces along root channels SC

On top surfaces of rock fragments TR

PED and VOID SURFACE FEATURES - COLOR—Use standard 

Munsell® notation (hue, value, chroma) to record feature color. 

Indicate whether the color is Moist (M) or Dry (D); e.g., 7.5R 5/8 M.

SOIL TEXTURE

Soil texture is the numerical proportion (weight percentage) 

of the sand, silt, and clay separates in the fine-earth fraction 

(≤2 mm). Soil texture is field estimated by hand or lab measured 

by hydrometer or pipette and placed within the textural triangle to 

obtain Texture Class.

Record the Texture Class; e.g., loam; or Subclass; e.g., fine 

sandy loam; or choose a Term in Lieu of Texture; e.g., gravel. If 

appropriate, use a Texture Class Modifier; e.g., gravelly loam.

NOTE: Soil Texture includes only the fine-earth fraction (≤2 mm). 

“Whole-soil Particle-Size Distribution” includes the fine-earth 

fraction (≤2 mm, wt %) and coarse fragments (>2 mm). (NOTE:
USDA-NRCS 2–37 September 2012

For fragments ≥76 mm in diameter, visually estimate the volume 

percent, which is then converted to a weight basis using the 

estimated particle density [ρd] and bulk density [Bd].)

TEXTURE CLASS—

Texture Class or 

Subclass

Code

Conv. NASIS

Coarse Sand cos COS

Sand s S

Fine Sand fs FS

Very Fine Sand vfs VFS

Loamy Coarse Sand lcos LCOS

Loamy Sand ls LS

Loamy Fine Sand lfs LFS

Loamy Very Fine Sand lvfs LVFS

Coarse Sandy Loam cosl COSL

Sandy Loam sl SL

Fine Sandy Loam fsl FSL

Very Fine Sandy Loam vfsl VFSL

Loam l L

Silt Loam sil SIL

Silt si SI

Sandy Clay Loam scl SCL

Clay Loam cl CL

Silty Clay Loam sicl SICL

Sandy Clay sc SC

Silty Clay sic SIC

Clay c C
USDA-NRCS 2–38 September 2012

100

100

100

90

90

90

80

80

80

70

70

70

60

60

60

50

40

40

40

30

30

30

20

20

20

10

10

10

Clay

Separate, %

Sand Separate, %

Silt Separate, %

sand

loamy

 sand

sandy loam

clay

sandy

clay

sandy clay loam

clay loam

loam

silty

clay

silty

clay loam

silt loam

silt

50

50

(Soil) Textural Triangle:

Fine Earth Texture Classes ( )

TEXTURE MODIFIERS—Conventions for using “Rock Fragment 

Texture Modifiers” and for using textural adjectives that convey the 

“% volume” ranges for Rock Fragments - Quantity and Size.

Frag. 

Content 

Vol. %

Rock Fragment Modifier Usage

<15 No texture class modifier (noun only; e.g., loam).

15 to <35 Use fragment-size adjective with texture class; 

e.g., gravelly loam.

35 to <60 Use “very” with fragment-size adjective with 

texture class; e.g., very gravelly loam.

60 to <90 Use “extremely” with fragment-size adjective with 

texture class; e.g., extremely gravelly loam.

≥90 No adjective or modifier. If ≤10% fine earth, use 

the appropriate fragment-size class name for the 

dominant size class; e.g., gravel. Use Terms Used 

in Lieu of Texture (see table on p. 2–43).
USDA-NRCS 2–39 September 2012

TEXTURE MODIFIERS—Quantity and Size adjectives.

Rock Fragments: 

Quantity and 

Size 1

Code Criteria: total (rock) 

fragment volume % 

dominated by

(name size) 1 Conv. NASIS

ROCK FRAGMENTS (>2 mm; ≥ Strongly Cemented)

Gravelly GR GR ≥15% but <35% gravel

Fine Gravelly FGR GRF ≥15% but <35% fine gravel

Medium Gravelly MGR GRM ≥15% but <35% med. gravel

Coarse Gravelly CGR GRC ≥15% but <35% coarse gravel

Very Gravelly VGR GRV ≥35% but <60% gravel

Extremely Gravelly XGR GRX ≥60% but <90% gravel

Cobbly CB CB ≥15% but <35% cobbles

Very Cobbly VCB CBV ≥35% but <60% cobbles

Extremely Cobbly XCB CBX ≥60% but <90% cobbles

Stony ST ST ≥15% but <35% stones

Very Stony VST STV ≥35% but <60% stones

Extremely Stony XST STX ≥60% but <90% stones

Bouldery BY BY ≥15% but <35% boulders

Extremely Bouldery XBY BYX ≥35% but <60% boulders

Channery CN CN ≥15% but <35% channers

Very Channery VCN CNV ≥35% but <60% channers

Extremely Channery XCN CNX ≥60% but <90% channers

Flaggy FL FL ≥15% but <35% flagstones

Very Flaggy VFL FLV ≥35% but <60% flagstones

Extremely Flaggy XFL FLX ≥60% but <90% flagstones

PARAROCK FRAGMENTS (>2 mm; < Strongly Cemented) 2, 3

Paragravelly PGR PGR (same criteria as for gravelly)

Very Paragravelly VPGR PGRV (same criteria as for very 

gravelly)

Extr. Paragravelly XPGR PGRX (same criteria as for extr. 

gravelly)

etc. etc. etc. (same criteria as for nonpara)
USDA-NRCS 2–40 September 2012

Rock Fragments: 

Quantity and 

Size 1

Code Criteria: total (rock) 

fragment volume % 

dominated by

(name size) 1 Conv. NASIS

COMPOSITE ROCK AND ARTIFACT FRAGMENTS 4

Gravelly - Artifactual GRART GRART (same criteria as for gravelly)

Very Gravelly - 

Artifactual VGRART GRVART (same criteria as for very gravelly)

Extremely Gravelly 

- Artifactual XGRART GRXART (same criteria as for extr. gravelly)

etc. etc. etc. (same criteria as for 

noncomposite)

1 The “Quantity” modifier (e.g., very) is the volume % whole soil 

of the total rock fragment content. The “Size” modifier (e.g., 

cobbly) is independently based on the largest, dominant fragment 

size. (See “Comparison of Particle-Size Classes” table; p. 2–45, 

first row.) For a size mixture (e.g., gravel and stones), a smaller 

size class is named if its quantity (%) sufficiently exceeds that 

of a larger size class. For field texture determination, a smaller 

rock fragment size class must exceed either 1.5 or 2 times the 

quantity (volume %) of a larger size class before it is named 

(e.g., 30% gravel and 14% stones=very gravelly, but 20% 

gravel and 14% stones=stony). For detailed naming criteria, see 

NSSH, Part 618, Subpart B, Exhibits, “Rock Fragment Modifier of 

Texture” (Soil Survey Staff, 2012c).

2 Use “Para” prefix if the rock fragments are soft (i.e., meet 

criteria for “para”). (Rupture Resistance – Cementation Class is 

< Strongly Cemented, and fragments do not slake [slake test: 

≈3 cm (1 inch) diam. block, air dried, then submerged in water 

for ≥1 hour; collapse/disaggregation=“slaking”].)

3 For “Para” codes, add “P” to “Size” and “Quantity” code terms. 

Precedes noun codes and follows quantity adjectives; e.g., 

paragravelly=PGR; very paragravelly=PGRV.

4 Used if a horizon contains both rock and artifact fragments

>2 mm that are both cohesive and persistent and whose 

combined % by volume is ≥15%; use appropriate Quantity Class 

(the dominant size fraction is named).
USDA-NRCS 2–41 September 2012

(COMPOSITIONAL) TEXTURE MODIFIERS 1, 2—Compositional 

adjectives.

Types Code Criteria

VOLCANIC

Ashy ASHY

Andic soil properties, and is neither 

hydrous nor medial, or ≥30% of the 

<2 mm fraction is 0.02 to 2.00 mm in 

size, ≥5% is volcanic glass, and the [Al 

+ 1/2 Fe, % by ammonium oxalate) x 

60] + % volc glass is ≥30

Hydrous HYDR

Andic soil properties, and with field 

moist 15 bar water content ≥100% of 

the dry weight

Medial MEDL

Andic soil properties, and with field 

moist 15 bar water content ≥30% to 

<100% of the dry weight, or ≥12% 

water content for air-dried samples

ORGANIC SOIL MATERIALS

Grassy 3 GS OM >15% (vol.) grassy fibers

Herbaceous 3 HB OM >15% (vol.) herbaceous fibers

Mossy 3 MS OM >15% (vol.) moss fibers

Woody 3 WD OM ≥15% (vol.) wood pieces or fibers

HIGHLY ORGANIC MINERAL MATERIALS

Highly Organic 4 HO

Organic carbon (wt %) is:

>5 to <20% (no mineral clays)

12 to <20% (if mineral clay is ≥60%)

or

5+ (clay % x 0.12 to <20%) (if mineral 

clay is <60%)

Mucky 5 MK Mineral soil >10% OM and <17% fibers

Peaty 5 PT Mineral soil >10% OM and >17% fibers

LIMNIC MATERIALS (used only with Histosols)

Coprogenous COP Limnic layer with many very small fecal 

pellets

Diatomaceous DIA Limnic layer composed of diatoms

Marly MR Light-colored limnic layer composed of 

CaCO3 mud
USDA-NRCS 2–42 September 2012

Types Code Criteria

ANTHROPOGENIC MATERIALS

Artifactual ART ≥15% but <35% (vol.) artifacts

Very Artifactual ARTV ≥35% but <60% (vol.) artifacts

Extremely 

Artifactual 2 ARTX ≥60% but <90% (vol.) artifacts

OTHER

Cemented CEM Material is “cemented” by ≥1 

cementing agents; does not slake

Gypsiferous GYP ≥15 to <40% (by weight) gypsum

Permanently 

Frozen PF e.g., Permafrost

1 (Compositional) Texture Modifiers can be used with the Soil 

Texture Name (e.g., gravelly ashy loam) or with Terms Used 

in Lieu of Texture (e.g., mossy peat). For complete definitions 

and usage of (Compositional) Texture Modifiers, see NSSH, 

Part 618.67 (Soil Survey Staff, 2012c).

2 If artifact fragments are >90% (by vol.), no texture is described 

and a Term Used in Lieu of Texture is applied (i.e., artifacts).

3 Used to modify muck, mucky peat, or peat terms in histic 

epipedons and organic horizons (of any thickness) that are 

saturated with water for ≥30 consecutive days in normal years 

(or are artificially drained), including those in Histels and 

Histosols (except Folists).

4 Used only with near-surface horizons of mineral soils saturated 

<30 cumulative days in normal years (and not artificially 

drained).

5 Designed for near-surface horizons saturated ≥30 cumulative 

days annually.
USDA-NRCS 2–43 September 2012

TERMS USED IN LIEU OF TEXTURE—nouns (used only if 

fragments or artifacts are >90% by volume). Bedrock, organic 

terms, gypsum materials, and permanent water have different 

criteria.

Terms Used in Lieu of Texture Code

SIZE (ROCK FRAGMENTS) ≥ Strongly Cemented

Gravel GR

Cobbles CB

Stones ST

Boulders BY

Channers CN

Flagstones FL

SIZE (PARAROCK FRAGMENTS) < Strongly Cemented

Paragravel PG

Paracobbles PCB

Parastones PST

Paraboulders PBY

Parachanners PCN

Paraflagstones PFL

COMPOSITION

Cemented/Consolidated:

Bedrock BR

Organic Soil Materials:

Highly Decomposed Plant Material (Oa) 1 HPM

Moderately Decomposed Plant Material (Oe) 1 MPM

Slightly Decomposed Plant Material (Oi) 1 SPM

Muck 2 (≈Oa) MUCK

Mucky Peat 2 (≈Oe; saturated, moderately 

decomposed organic matter) MPT

Peat 2 (≈Oi) PEAT

Other:

Artifacts 3 (human-manufactured materials) ART

Coarse Gypsum Material CGM

Fine Gypsum Material FGM

Ice 4, 5 (permanent, subsurface) ICE

Material 6 MAT

Water 5 (permanent, subsurface) W
USDA-NRCS 2–44 September 2012

1 Use only with organic horizons of mineral and organic soils that 

are saturated <30 cumulative days in normal years (and are not

artificially drained).

2 Use only with organic horizons (of any thickness) of mineral and 

organic soils that are saturated ≥30 cumulative days in normal 

years or are artificially drained.

3 “Artifacts” is used only to denote presence of artificial materials 

associated with human activities (bitumen, bricks, construction 

debris, garbage, etc.).

4 Use only for layers found below the soil surface (e.g., a floating 

bog).

5 Used for permanent (nonseasonal), massive, subsurface ice; e.g., 

a glacic layer; proposed in NASIS.

6 “Material” is used only in combination with Compositional Texture 

Modifiers (p. 2–41); e.g. woody material; medial material. In 

NASIS, “Cemented Material” denotes any cemented soil material 

(i.e., duripan, ortstein, petrocalcic, petroferric, petrogypsic).

[ Footnotes below apply to the following table: ]

1 Soil Survey Staff, 2011; p. 489.

2 Soil Survey Staff, 2011; p. 33. Note: Mineralogy studies may 

subdivide clay into three size ranges: fine (<0.08 um), medium 

(0.08–0.2 μm), and coarse (0.2–2 μm) (Jackson, 1969).

3 The Kellogg Soil Survey Laboratory (Lincoln, NE) uses a no. 300 

sieve (0.047-mm opening) for the USDA sand/silt measurement. 

A no. 270 sieve (0.053-mm opening) is more readily available 

and widely used.

4 Soil Survey Staff, 1951; p. 207.

5 ASTM, 2011; ASTM designation D2487–92.

6 AASHTO, 1997a.

7 AASHTO, 1997b.

8 Ingram, 1982.
USDA-NRCS 2–45 September 2012
USDA-NRCS 2–46 September 2012

ROCK and OTHER FRAGMENTS

These are discrete, water-stable particles >2 mm. Hard fragments 

(e.g., rock) have a Rupture Resistance - Cementation Class ≥ 

Strongly Cemented. Softer fragments (e.g., pararock) are less 

strongly cemented. (NOTE: Artifacts are addressed separately 

following this section [p. 2–49].) Describe Kind, Volume Percent

(classes given below), Roundness or Shape, Size (mm), and 

Hardness; e.g., granite, 17%, subangular, gravel, indurated; or 

GRA, 17%, SA, GR, I.

ROCK and OTHER FRAGMENTS - KIND (called FRAGMENTS

in NASIS)—Use the choice list given for Bedrock - Kind and the 

additional choices in the table below. NOTE: Interbedded rocks 

from the “Bedrock - Kind” table are not appropriate choices or 

terminology for rock fragments.

Kind Code Kind Code

Includes all choices in Bedrock - Kind (except Interbedded), 

plus:

calcrete (caliche) 

fragments 1 CA

metamorphic 

rock fragments, 

unspecified 2

MMR

carbonate concretions CAC mixed rock

fragments 3 MXR

carbonate nodules CAN ortstein fragments ORF

carbonate rocks 2 CAR petrocalcic fragments PEF

charcoal fragments CH petroferric fragments TCF

cinders CI petrogypsic fragments PGF

durinodes DNN plinthite nodules PLN

duripan fragments DUF quartz fragments QUA

foliated metamorphic 

rocks 2 FMR quartzite fragments QZT

gibbsite concretions GBC scoria fragments SCO

gibbsite nodules GBN

sedimentary 

rock fragments, 

unspecified 2

SED

igneous rock fragments, 

unspecified 2 IGR shell fragments SHF

iron-manganese 

concretions FMC silica concretions SIC

iron-manganese nodules FMN volcanic bombs VB
USDA-NRCS 2–47 September 2012

Kind Code Kind Code

ironstone nodules FSN

volcanic rock 

fragments, 

unspecified 2

VOL

lapilli LA wood fragments WO

1 Fragments strongly cemented by carbonate; may include 

fragments derived from petrocalcic horizons.

2 Generic rock names may be appropriate for identifying fragments 

(e.g., a cobble) but are too general and should not be used to 

name Bedrock - Kind.

3 Numerous unspecified fragment lithologies are present, as in till 

or alluvium; not for use with residuum.

ROCK and OTHER FRAGMENTS - VOLUME PERCENT 

(Quantity)—Estimate the quantity (volume percent) of rock and 

other fragments present. NOTE: Refer to the “Total (rock) fragment 

volume percent” column found under Texture Modifiers - 

Quantity and Size table (p. 2–39).

ROCK and OTHER FRAGMENTS - SIZE CLASSES AND 

DESCRIPTIVE TERMS—

Size 1 Noun Adjective 2

SHAPE—SPHERICAL or CUBELIKE (discoidal, subdiscoidal, 

or spherical)

>2 - 76 mm diam. gravel gravelly

 >2 - 5 mm diam. fine gravel fine gravelly

 >5 - 20 mm diam. medium gravel medium gravelly

 >20 - 76 mm diam. coarse gravel coarse gravelly

>76 - 250 mm diam. cobbles cobbly

>250 - 600 mm diam. stones stony

>600 mm diam. boulders bouldery

SHAPE—FLAT (prismoidal or subprismoidal)

>2 - 150 mm long channers channery

>150 - 380 mm long flagstones flaggy

>380 - 600 mm long stones stony

>600 mm long boulders bouldery

1 Fragment sizes measured by sieves; class limits have a greater 

lower limit.
USDA-NRCS 2–48 September 2012

2 For a mixture of sizes (e.g., both gravel and stones present), 

the largest size class (most mechanically restrictive) is 

named. A smaller size class is named only if its quantity (%) 

sufficiently exceeds that of a larger size class. For field texture 

determination, a smaller size class must exceed 2 times the 

quantity (volume %) of a larger size class before it is named 

(e.g., 30% gravel and 14% stones=very gravelly; but 20% gravel 

and 14% stones=stony). For more explicit naming criteria, see 

NSSH, Part 618, Subpart B, Exhibits, “Rock Fragment Modifier of 

Texture” (Soil Survey Staff, 2012c).

ROCK and OTHER FRAGMENTS - ROUNDNESS—Estimate the 

relative roundness of rock fragments; use the following classes.

Roundness

Class Code Criteria: visual estimate 1

Very Angular VA

[Use Roundness graphic on

p. 2–49]

Angular AN

Subangular SA

Subrounded SR

Rounded RO

Well Rounded WR

1 The criteria consist of a visual estimation; use the following 

graphic.

Estimate the relative roundness of rock fragments. (Ideally, use 

the average roundness of 50 or more fragments.) The conventional 

geologic and engineering approach is presented in the following 

graphic. NOTE: NRCS does not quantify Sphericity. It is included 

here for completeness and to show the Fragment Roundness 

range.
USDA-NRCS 2–49 September 2012

Very

Angular

0.5 

Angular

1.5 

Subangular

2.5 

Subrounded

3.5 

Rounded

4.5 

Well

Rounded

5.5 

Discoidal

0.5 

Subdiscoidal

1.5 

Spherical

2.5 

Subprismoidal

3.5

Prismoidal

4.5

Sphericity

Roundness 1, 2

1 After Powers, 1953.

2 Numerical values below Roundness and Sphericity headings 

are class midpoints (median rho values; Folk, 1955) used in 

statistical analysis.

ROCK and OTHER FRAGMENTS - HARDNESS (called fragment_

hardness in NASIS)—Describe the relative force required to crush 

the fragment. Use the same criteria and classes as the Rupture 

Resistance for Blocks, Peds, and Clods - Cementation column 

(p. 2–63); e.g., Moderately Cemented (exclude the Noncemented

class).

ARTIFACTS (Human-derived)

These are discrete, water-stable fragments of human origin 

(cultural byproducts) (called Human_artifacts in NASIS). They 

are described separately from Rock and Other Fragments due to 

their unique properties and nongeologic origins and due to unique 

historical and cultural implications.

Describe Kind, Quantity (vol. percentage), Roundness, Shape, 

Cohesion, Penetrability, Persistence, Safety.
USDA-NRCS 2–50 September 2012

ARTIFACTS - KIND—Record the dominant types of human 

artifacts present by horizon/layer. (Used in NASIS primarily for % 

passing sieve calculation.) All fragments ≥2 mm.

Kind

bitumen (asphalt) fly ash

boiler slag glass

bottom ash metal

brick paper

cardboard plasterboard

carpet plastic

cloth potsherd

coal combustion byproducts rubber (tires, etc.)

concrete (fragments) treated wood

debitage (stone tool flakes) untreated wood

ARTIFACTS - QUANTITY—Estimate the relative amount 

(volume %) of artifacts by horizon/layer. In NASIS, estimate a 

Representative Value (RV).

Quantity Criteria

# (volume percent)

ARTIFACTS - ROUNDNESS—Estimate the dominant extent of 

roundness of the artifacts by horizon/layer. (Refer to Rock and 

Other Fragments - Roundness graphic on p. 2–49.)

Roundness Class Code

Angular AN

Rounded RO

Subangular SA

Subrounded SR

Very Angular VA

Well Rounded WR
USDA-NRCS 2–51 September 2012

ARTIFACTS - SHAPE—Describe the dominant form (shape) of the 

artifacts by horizon/layer.

Shape Class Code Criteria

Elongated E

One dimension (length, width, or 

height) is 3X longer than either of the 

others.

Equidimensional Q Length, width, height are 

approximately the same.

Flat F

One dimension is <1/3 that of either of 

the others, and one dimension is <3X 

that of the intermediate.

Irregular I Branching or convoluted form.

ARTIFACTS - COHESION—Describe the dominant relative 

fragment integrity.

Cohesion Class Code Criteria

Cohesive C Cannot be readily broken to <2 mm 

pieces.

Noncohesive N Easily broken to <2 mm pieces by 

hand or simple crushing.

ARTIFACTS - PENETRABILITY—Describe the prevalent relative 

ease of penetration of artifacts by external mechanical force by 

horizon/layer.

Penetrability Class Code Criteria

Nonpenetrable N Roots cannot penetrate through or 

between artifacts.

Penetrable P Roots can penetrate through or 

between artifacts.

ARTIFACTS - PERSISTENCE—Describe the dominant relative 

extent.

Persistence Class Code Criteria

Nonpersistent N Susceptible to relatively rapid 

weathering or decay (expected loss 

in <10 years).

Persistent P Expected to remain intact in soil for 

>10 years.
USDA-NRCS 2–52 September 2012

ARTIFACTS - SAFETY—Describe the dominant relative level of 

chemical safety of artifacts present.

Safety Class Code Criteria

Innocuous artifacts IA Harmless to living beings (e.g., 

brick, wood, glass, etc.).

Noxious artifacts NA Potentially harmful or destructive 

to living beings (e.g., batteries, 

garbage, petroleum products).

(SOIL) STRUCTURE

(Soil) structure is the naturally occurring arrangement of soil 

particles into aggregates that results from pedogenic processes. 

Record Grade, Size, and Type. For compound structure, list each 

size and type; e.g., medium and coarse SBK parting to fine GR. 

Lack of structure (structureless) has two end members: massive 

(MA) or single grain (SG). A complete example is: weak, fine, 

subangular blocky or 1, f, sbk.

(SOIL STRUCTURE) - TYPE (formerly Shape)—Record the 

dominant type of ped, by layer; e.g., granular or gr. If a prevailing 

large shape readily breaks into smaller units, record as “(larger 

type) parting to (smaller type)”; e.g., prismatic parting to 

subangular blocky.
USDA-NRCS 2–53 September 2012

Type

Code

Criteria: definition

Conv. NASIS

NATURAL SOIL STRUCTURAL UNITS (pedogenic structure)

Granular gr GR Small polyhedrals with curved or 

very irregular faces.

Angular 

Blocky abk ABK Polyhedrals with faces that intersect at sharp angles (planes).

Subangular 

Blocky sbk SBK Polyhedrals with subrounded and planar faces lacking sharp angles.

Lenticular lp LP

Overlapping, lens-shaped peds 

generally parallel to the soil surface 

that are thick at the center and 

taper toward the edges; formed 

by active or relict periglacial 

frost processes. Most common 

in soils with moderate to high 

water-holding capacity in moist 

conditions.

Platy pl PL Flat and platelike units.

Wedge wg WEG

Elliptical, interlocking lenses that 

terminate in acute angles, bounded 

by slickensides; not limited to 

vertic materials.

Prismatic pr PR Vertically elongated units; flat tops.

Columnar cpr COL

Vertically elongated units with 

rounded tops that commonly are 

“bleached.”

STRUCTURELESS

Single 

Grain sg SGR No structural units; entirely noncoherent; e.g., loose sand.

Massive m MA

No structural units; material is a 

coherent mass (not necessarily 

cemented).

ARTIFICIAL EARTHY FRAGMENTS OR CLODS1

(nonpedogenic structure)

Cloddy 1 — CDY

Irregular blocks created by artificial 

disturbance; e.g., tillage or 

compaction.

1 Used only to describe oversized, “artificial” earthy units that are 

not pedogenically derived soil structural units; e.g., the direct 

result of mechanical manipulation; use Blocky Structure Size

criteria.
USDA-NRCS 2–54 September 2012

Prismatic

(Subangular) (Angular)

Examples of Soil Structure Types

Blocky

Massive

(Continuous, unconsolidated mass) 

Wedge

Platy

Lenticular

Single Grain

(Loose mineral/rock grains) 

Granular

(Soil aggregates)

Columnar

Structureless Types

Example of Wedge Structure, Gilgai Microfeature,

and Microrelief

Master

slickensides

CaCO3

microhigh

microlow

microslope

microslope

3-10 m

Half-wedge

(merging

slickensides)

2m

Parallelepiped

Wedge-shaped ped

Bowl

(modified from Lynn and Williams, 1992)
USDA-NRCS 2–55 September 2012

(SOIL STRUCTURE) - GRADE—

Grade Code Criteria

Structureless 0 No discrete units observable in place or in 

hand sample.

Weak 1 Units are barely observable in place or in a 

hand sample.

Moderate 2 Units well formed and evident in place or 

in a hand sample.

Strong 3 Units are distinct in place (undisturbed 

soil) and separate cleanly when disturbed.

(SOIL STRUCTURE) - SIZE—

Size

Class

Code

Criteria: structural unit size 1 (mm) Conv. NASIS

Granular, 

Platy 2, 

(Thickness)

Columnar, 

Prismatic, 

Wedge 3

(Diameter)

Angular & 

Subangular 

Blocky and 

Lenticular

(Diameter)

Very Fine

(Very Thin) 2

vf

(vn)

VF

(VN) < 1 < 10 < 5

Fine

(Thin) 2

f

(tn)

F

(TN) 1 to < 2 10 to < 20 5 to < 10

Medium

(Medium)

m

(m)

M

(M) 2 to < 5 20 to < 50 10 to < 20

Coarse

(Thick) 2

co

(tk)

CO

(TK) 5 to < 10 50 to <100 20 to < 50

Very Coarse

(Very Thick) 2

vc

(vk)

VC

(VK) ≥ 10 100 to<500 ≥ 50

Extremely 

Coarse

ec

(—)

EC

(—) — ≥500 —

1 Size limits always denote the smallest dimension of the structural 

units.

2 For platy structures only, substitute Thin for Fine and Thick for 

Coarse in the Size Class names.

3 Wedge structure is generally associated with Vertisols (for which 

it is a requirement) or related soils (e.g., “Vertic” subgroups) with 

high amounts of smectitic clays.
USDA-NRCS 2–56 September 2012
USDA-NRCS 2–57 September 2012
USDA-NRCS 2–58 September 2012
USDA-NRCS 2–59 September 2012
USDA-NRCS 2–60 September 2012
USDA-NRCS 2–61 September 2012
USDA-NRCS 2–62 September 2012

CONSISTENCE

Consistence is the degree and kind of cohesion and adhesion that 

soil exhibits and/or the resistance of soil to deformation or rupture 

under an applied stress. Soil-water state strongly influences 

consistence. Field evaluations of consistence include: Rupture 

Resistance (Blocks, Peds, and Clods; or Surface Crusts and 

Plates), Manner of Failure (Brittleness, Fluidity, Smeariness),

Stickiness, Plasticity, and Penetration Resistance. Historically, 

consistence applied to dry, moist, or wet soil as observed in the 

field. Wet consistence evaluated stickiness and plasticity. Rupture 

Resistance now applies to dry soils and to soils in a water state 

from moist through wet. Stickiness and Plasticity of soil are 

independent evaluations.

RUPTURE RESISTANCE—A measure of the strength of soil to 

withstand an applied stress. Separate estimates of Rupture 

Resistance are made for Blocks/Peds/Clods and for Surface 

Crusts and Plates of soil. Block-shaped specimens should be 

approximately 2.8 cm across. If 2.8-cm cubes (e.g., ≈ 2.5-3.1 cm, 

or 1 inch) are not obtainable, use the following equation and the 

table below to calculate the stress at failure: [(2.8 cm/cube length 

cm)2 X estimated stress (N) at failure)]; e.g., for a 5.6-cm cube 

[(2.8/5.6)2 X 20 N] = 5 N ⇒ Soft Class. Plate-shaped specimens 

(surface crusts or platy structure) should be approximately 

1.0-1.5 cm long by 0.5 cm thick (or the thickness of occurrence, if 

<0.5 cm thick).
USDA-NRCS 2–63 September 2012

RUPTURE RESISTANCE FOR:

Blocks, Peds, and Clods—Estimate the class by the force required 

to rupture (break) a soil unit. Select the column for the appropriate 

soil water state (dry vs. moist) and/or the Cementation column, if 

applicable.

Dry 1 Moist 1 Cementation 2 Specimen 

Fails Under Class Code 3 Class Code 3 Class Code 3

Loose L Loose L

[Not Applicable] [Intact specimen 

not obtainable] d(lo) m(lo)

Soft S Very 

Friable

VFR NoncementedNC Very slight force 

between fingers.

<8 N d(so) m(vfr)

Slightly 

Hard

SH Friable FR Extremely 

Weakly 

Cemented

EW

Slight force 

between fingers.

8 to <20 N

d(sh) m(fr)

Mod. 

Hard

MH Firm FI Very 

Weakly 

Cemented

VW

Moderate force 

between fingers.

20 to <40 N

d(h) m(fi)

Hard HA Very 

Firm

VFI Weakly 

Cemented

W Strong force 

between fingers.

40 to <80 N d(vh) m(vfi) c(w)

Very 

Hard

VH Extr. 

Firm

EF Moderately 

Cemented

M Moderate force 

between hands.

80 to <160 N d(vh) m(efi)

Extr. 

Hard

EH Slightly 

Rigid

SR Strongly 

Cemented

ST Foot pressure by 

full body weight.

160 to <800 N d(eh) m(efi) c(s)

Rigid R Rigid R Very 

Strongly 

Cemented

VS

Blow of <3 J but 

not body weight.

800 N to <3 J

d(eh) m(efi)

Very 

Rigid

VR Very 

Rigid

VR Indurated I Blow of ≥3 J

(3 J = 2 kg 

weight dropped 

15 cm) d(eh) m(efi) c(I)

1 Dry Rupture Resistance column applies to soils that are 

moderately dry or drier (Moderately Dry and Very Dry Soil 

Water State subclasses). Moist column applies to soils that are 

slightly dry or wetter (Slightly Dry through Satiated Soil Water 

State subclasses) (Soil Survey Division Staff, 1993, p. 91).
USDA-NRCS 2–64 September 2012

2 This is not an immediate field test; specimen must first be air 

dried and then submerged in water for a minimum of 1 hour prior 

to test; collapse/disaggregation=“slaking” (Soil Survey Division 

Staff, 1993, p. 173).

3 Codes in parentheses (e.g., d(lo); Soil Survey Staff, 1951) are 

obsolete.

Surface Crust and Plates—

Class (air dried) Code Force 1 (Newtons)

Extremely Weak EW Not Obtainable

Very Weak VW Removable, < 1N

Weak W 1 to < 3N

Moderate M 3 to < 8N

Moderately Strong MS 8 to < 20N

Strong S 20 to < 40N

Very Strong VS 40 to < 80N

Extremely Strong ES ≥ 80N

1 For operational criteria (field estimates of force [N]), use the Fails 

Under column in the “Rupture Resistance for Blocks, Peds, Clods” 

table.

CEMENTING AGENTS (called rupture_resist_cem_agent in 

NASIS)—Record kind of cementing agent, if present.

Kind Code 1

carbonates K

gypsum 2 G

humus H

iron I

silica (SiO2) S

1 Conventional codes traditionally consist of the entire material 

name or its chemical symbols; e.g., silica or SiO2. Consequently, 

the Conv. code column would be redundant and is not shown in 

this table.

2 Gypsum is not a true cement but functionally behaves as such.
USDA-NRCS 2–65 September 2012

MANNER OF FAILURE—The rate of change and the physical 

condition soil attains when subjected to compression. Samples are 

moist or wetter.

Failure 

Class Code Criteria: related field operation

BRITTLENESS Use a 3-cm block

(press between thumb and forefinger)

Brittle BR Ruptures abruptly (“pops” or shatters).

Semideformable SD Rupture occurs before compression to 

<1/2 original thickness.

Deformable DF Rupture occurs after compression to ≥1/2 

original thickness.

FLUIDITY 1 Use a palmful of soil

(squeeze in hand)

Nonfluid NF After full compression, no soil flows 

through the fingers.

Slightly Fluid SF

After full compression is exerted, some soil 

flows through fingers; most remains in the 

palm.

Mod. Fluid MF

After full pressure is exerted, most soil 

flows through fingers; some remains in the 

palm.

Very Fluid VF

Under very gentle pressure, most soil flows 

through the fingers as a slightly viscous 

fluid; very little or no residue remains in 

the palm of the hand.

SMEARINESS Use a 3-cm block

(press between thumb and forefinger)

Nonsmeary 2 NS

At failure, the sample does not change 

abruptly to fluid, fingers do not skid, no 

smearing occurs.

Weakly 

Smeary 2 WS

At failure, the sample changes abruptly to 

fluid, fingers skid, soil smears, little or no 

water remains on fingers.

Moderately 

Smeary 2 MS

At failure, the sample changes abruptly to 

fluid, fingers skid, soil smears, some water 

remains on fingers.

Strongly 

Smeary 2 SM

At failure, the sample abruptly changes 

to fluid, fingers skid, soil smears and is 

slippery, water is easily seen on fingers.
USDA-NRCS 2–66 September 2012

1 See additional comments on fluidity under Subaqeous Soils

(p. 2–105).

2 Smeariness failure classes are used dominantly with materials 

displaying andic soil properties (and some spodic materials).

STICKINESS—The capacity of soil to adhere to other objects. 

Stickiness is estimated at the moisture content that displays the 

greatest adherence when pressed between thumb and forefinger.

Stickiness 

Class

Code Criteria: work moistened soil 

Conv. NASIS between thumb and forefinger

Nonsticky (w) so SO Little or no soil adheres to fingers 

after release of pressure.

Slightly 

Sticky (w) ss SS

Soil adheres to both fingers after 

release of pressure. Soil stretches 

little on separation of fingers.

Moderately 

Sticky 1 (w) s MS

Soil adheres to both fingers after 

release of pressure. Soil stretches 

some on separation of fingers.

Very Sticky (w) vs VS

Soil adheres firmly to both fingers 

after release of pressure. Soil 

stretches greatly upon separation 

of fingers.

1 Historically, the Moderately Sticky class was simply called Sticky.

PLASTICITY—The degree to which “puddled” or reworked soil 

can be permanently deformed without rupturing. The evaluation is 

made by forming a roll (wire) of soil at a water content where the 

maximum plasticity is expressed.

Plasticity 

Class

Code Criteria: make a roll of soil

Conv. NASIS 4 cm long

Nonplastic (w) po PO

Will not form a roll 6 mm in 

diameter, or if a roll is formed, it 

can’t support itself if held on end.

Slightly 

Plastic (w) ps SP 6 mm diameter roll supports itself; 4 mm diameter roll does not.

Moderately 

Plastic 1 (w) p MP 4 mm diameter roll supports itself; 2 mm diameter roll does not.

Very 

Plastic (w) vp VP 2 mm diameter roll supports its weight.

1 Historically, the Moderately Plastic class was simply called Plastic.
USDA-NRCS 2–67 September 2012

2 mm 4 mm 6 mm 4 cm

PENETRATION RESISTANCE—The ability of soil in a confined 

(field) state to resist penetration by a rigid object of specified size. 

A pocket penetrometer (Soil-Test Model CL-700) with a rod diameter 

of 6.4 mm (area 20.10 mm2) and insertion distance of 6.4 mm 

(note line on rod) is used for the determination. An average of 

five or more measurements should be used to obtain a value for 

penetration resistance.

NOTE: The pocket penetrometer has a scale of 0.25 to 4.5 tons/ft2

(tons/ft2 ≈ kg/cm2). The penetrometer does not directly measure 

penetration resistance. The penetrometer scale is correlated to and 

gives a field estimate of unconfined compressive strength of soil as 

measured with a Tri-Axial Shear device. The table below converts 

the scale reading on the pocket penetrometer to penetration 

resistance in MPa. Penetrometer readings are dependent on the 

spring type used. Springs of varying strength are needed to span 

the range of penetration resistance found in soil.

Penetrometer 

Scale Reading Spring Type 1, 2, 3

tons/ft2 Original 

MPa

Lee

MPa

Jones 11 

MPa

Jones 323 

MPa

0.25 0.32 L 0.06 VL 1.00 M 3.15 H

0.75 0.60 0.13 L 1.76 4.20

1.00 0.74 0.17 2.14 H 4.73

1.50 1.02 M 0.24 2.90 5.78

2.75 1.72 0.42 4.80 8.40 EH

3.50 2.14 H 0.53 — —

1 On wet or “soft” soils, a larger “foot” may be needed (Soil Survey 

Division Staff, 1993).

2 Each bolded value highlights the force associated with a rounded 

value on the penetrometer scale that is closest to a Penetration 

Resistance Class boundary. The bolded letter represents the 

Penetration Resistance Class from the following table (e.g., M

indicates the Moderate class).

3 Each spring type spans only a part of the range of penetration 

resistance possible in soils; various springs are needed to span all 

Penetration Resistance Classes.
USDA-NRCS 2–68 September 2012

Penetration Resistance Class (called Penetration Resistance

in NASIS)—Record the appropriate class, by horizon or layer, based 

on the average value of five or more measurements with a pocket 

penetrometer.

Penetration 

Resistance Class

Code Criteria: Penetration 

Resistance (MPa)

Extremely Low EL < 0.01

Very Low VL 0.01 to < 0.1

Low L 0.1 to < 1

Moderate M 1 to < 2

High H 2 to < 4

Very High VH 4 to < 8

Extremely High EH ≥ 8

PENETRATION ORIENTATION—Record the orientation of 

the pocket penetrometer used to determine the Penetration 

Resistance Class.

Orientation Code Criteria

Horizontal H Oriented perpendicular to a vertical pit face

Vertical 1 V Oriented perpendicular to the ground 

surface

1 The conventional (preferred) orientation.
USDA-NRCS 2–69 September 2012

EXCAVATION DIFFICULTY—The relative force or energy required 

to dig soil out of place. Describe the Excavation Difficulty Class

and the moisture condition (moist or dry, but not wet); use the 

“(Soil) Water State” table; e.g., moderate, moist or M, M. Estimates 

can be made for either the most limiting layer or for each horizon.

Class Code Criteria

Low L Excavation by tile spade requires arm 

pressure only; impact energy or foot pressure 

is not needed.

Moderate M Excavation by tile spade requires impact 

energy or foot pressure; arm pressure is 

insufficient.

High H Excavation by tile spade is difficult but easily 

done by pick using over-the-head swing.

Very High VH Excavation by pick with over-the-head swing 

is moderately to markedly difficult. Backhoe 

excavation by a 50- to 80-hp tractor can be 

made in a moderate time.

Extremely 

High

EH Excavation via pick is nearly impossible. 

Backhoe excavation by a 50- to 80-hp tractor 

cannot be made in a reasonable time.
USDA-NRCS 2–70 September 2012

ROOTS

Record the Quantity, Size, and Location of roots in each horizon. 

NOTE: Describe Pores using the same Quantity and Size classes 

and criteria as those for Roots (use the combined tables). A 

complete example for roots is: Many, fine, roots In mat at top of 

horizon or 3, f (roots), M.

ROOTS (and PORES) - QUANTITY—Describe the quantity 

(number) of roots for each size class in a horizontal plane. (NOTE:

Typically, this is done across a vertical plane, such as a pit face.) 

Record the average quantity from three to five representative unit 

areas. CAUTION: The unit area that is evaluated varies with the 

Size Class of the roots being considered. Use the appropriate unit 

area stated in the Soil Area Assessed column of the “Size (Roots 

and Pores)” table (also see following graphic). In NASIS, record 

the actual number (#) of roots/unit area (NASIS then assigns the 

appropriate class). Use class names in narrative description.

Quantity

Class 1

Code Average Count 2

Conv. NASIS (per assessed area)

Few 1 # <1 per area

 Very Few 1 — # <0.2 per area

 Moderately Few 1 — # 0.2 to <1 per area

Common 2 # 1 to <5 per area

Many 3 # ≥5 per area

1 The Very Few and Moderately Few subclasses can be used for 

roots (optional) but do not apply to pores.

2 The applicable area for appraisal varies with the size of roots or 

pores. Use the appropriate area stated in the Soil Area Assessed

column of the “Size (Roots and Pores)” table or use the following 

graphic.

ROOTS (and PORES) - SIZE—(See the following graphic for size.)

Size

Class

Code

Diameter Soil Area 

Assessed 1

Conv. NASIS

Very Fine vf VF < 1 mm 1 cm2

Fine f F 1 to < 2 mm 1 cm2

Medium m M 2 to < 5 mm 1 dm2

Coarse co C 5 to <10 mm 1 dm2

Very Coarse vc VC ≥10 mm 1 m2

1 One dm2=a square that is 10 cm on a side, or 100 cm2.
USDA-NRCS 2–71 September 2012

ROOTS (and PORES) - QUANTITY—Soil area to be assessed.

1 mm 2 mm

10 x 10 cm 100 x 100 cm

(box not shown)

Assessment

Area:

1 cm

1 cm

VF F

5 mm 10 mm

M C VC

10 cm

(1 dm)

10 cm
USDA-NRCS 2–72 September 2012

ROOTS - LOCATION (Roots only)—Identify where roots occur.

Location Code

Between peds P

In cracks C

In mat at top of horizon 1 M

Matted around rock fragments R

Throughout T
USDA-NRCS 2–73 September 2012

1 Describing a root mat at the top of a horizon rather than at the 

bottom or within the horizon flags the horizon that restricts root 

growth.

PORES (DISCUSSION)

Pores are the air- or water-filled voids in soil. Historically, 

description of soil pores, called “nonmatrix” pores in the Soil 

Survey Manual (Soil Survey Division Staff, 1993), excluded 

interstructural voids, cracks, and, in some schemes, interstitial 

pores. Interstructural voids (i.e., the subplanar fractures between 

peds; also called interpedal or structural faces/planes), which 

can be inferred from soil structure descriptions, are not recorded 

directly. Cracks can be assessed independently (Soil Survey Division 

Staff, 1993). Interstitial pores (i.e., visible, primary packing voids) 

may be visually estimated, especially for fragmental soils, or 

can be inferred from soil porosity, bulk density, and particle-size 

distribution. Clearly, one cannot assess the smallest interstitial 

pores (e.g., <0.05 mm) in the field. Field observations are limited 

to those that can be seen through a 10X hand lens or larger. Field 

estimates of interstitial pores are considered to be somewhat 

tenuous but still useful.

PORES

Describe the Quantity and Size of pores for each size class, by 

horizon, in a horizontal plane. (NOTE: Typically, this is actually 

assessed on a vertical face.) Description of soil pore Shape and 

Vertical Continuity is optional. A complete example for pores is: 

common, medium, tubular pores, throughout or c, m, TU (pores), T.

PORES - QUANTITY—See and use Quantity (Roots and Pores).

PORES - SIZE—See and use Size (Roots and Pores).

PORES - SHAPE (or Type)—Record the dominant form (or “type”) 

of pores discernible with a 10X hand lens and by the unaided eye. 

(See following graphic.)

Description Code Criteria

SOIL PORES 1

Dendritic 

Tubular DT Cylindrical, elongated, branching voids; e.g., empty root channels.

Irregular IG Nonconnected cavities, chambers; e.g., 

vughs; various shapes.

Tubular TU Cylindrical and elongated voids; e.g., worm 

tunnels.
USDA-NRCS 2–74 September 2012

Description Code Criteria

Vesicular VE

Ovoid to spherical voids; e.g., solidified 

pseudomorphs of entrapped gas bubbles 

concentrated below a crust; most common 

in arid and semiarid environments.

PRIMARY PACKING VOIDS 2

Interstitial IR Voids between sand grains or rock frags.

1 Also called “Nonmatrix Pores” (Soil Survey Division Staff, 1993).

2 Primary Packing Voids include a continuum of sizes. As used here, 

they have a minimum size that is defined as pores that are visible 

with a 10X hand lens. Primary Packing Voids: also called “Matrix 

Pores” (Soil Survey Division Staff, 1993).

Rock fragments Sand

Interstitial

(e.g., primary packing voids) 

Fine earth

Vesicular

(e.g., isolated, spherical-ovoid cavities) 

Irregular

(e.g., vughs)

Tubular

(e.g., small worm tunnels)

Dendritic Tubular

(e.g., abandoned root channels) 
USDA-NRCS 2–75 September 2012

PORES - VERTICAL CONTINUITY—The average vertical distance 

through which the minimum pore diameter exceeds 0.5 mm. Soil 

must be moist or wetter.

Class

Code Criteria:

Conv. NASIS vertical distance

Low — L < 1 cm

Moderate — M 1 to < 10 cm

High — H ≥ 10 cm

CRACKS

Cracks (also called “Extra-Structural Cracks”; Soil Survey Division 

Staff, 1993) are fissures other than those attributed to soil 

structure. Cracks are commonly vertical, subplanar, and polygonal 

and are the result of desiccation, dewatering, or consolidation of 

earthy material. Cracks are much longer and can be much wider 

than planes that surround soil structural units, such as prisms and 

columns. Cracks are key to preferential flow, also called “bypass 

flow” (Bouma et al., 1982), and are a primary cause of temporal 

(transient) changes in ponded infiltration and hydraulic conductivity 

in soils (Soil Survey Division Staff, 1993). Cracks are primarily 

associated with, but not restricted to, clayey soils and are most 

pronounced in high shrink-swell soils (high COLE value). Record the 

Relative Frequency (estimated average number per m2), Depth

(average), and Kind. A complete example is: 3, 25 cm deep, 

reversible trans-horizon cracks.

Trans-horizon

cracks

Crust-related

cracks 

Soil

structure

(subplanar,

inter-ped

voids)

B

C

Ap

Crust

Horizon
USDA-NRCS 2–76 September 2012

CRACKS - KIND—Identify the dominant types of fissures.

Kind Code 1 General Description

CRUST-RELATED CRACKS 2 (shallow, vertical cracks related 

to crusts; derived from raindrop-splash and soil puddling 

followed by dewatering/consolidation and desiccation)

Reversible 

CrustRelated 

Cracks 3

RCR Very shallow (e.g., 0.1-0.5 cm); very 

transient (generally persist less than a few 

weeks); formed by drying from surface 

down; minimal seasonal influence on 

ponded infiltration (e.g., raindrop crust 

cracks).

Irreversible 

CrustRelated 

Cracks 4

ICR Shallow (e.g., 0.5-2 cm); seasonally 

transient (not present year-round nor 

every year); minor influence on ponded 

infiltration (e.g., freeze-thaw crust and 

associated cracks).

TRANS-HORIZON CRACKS 5 (deep, vertical cracks that 

commonly extend across more than one horizon and may 

extend to the surface; derived from wetting and drying or 

original dewatering and consolidation of parent material)

Reversible 

TransHorizon 

Cracks 6

RTH Transient (commonly seasonal; close when 

rewetted); large influence on ponded 

infiltration and Ksat; formed by wetting 

and drying of soil (e.g., Vertisols, vertic 

subgroups).

Irreversible 

TransHorizon 

Cracks 7

ITH Permanent (persist year-round; see Soil 

Taxonomy), large influence on ponded 

infiltration and Ksat (e.g., extremely coarse 

subsurface fissures within glacial till; 

drained polder cracks).

1 No conventional codes; use entire term. NASIS codes are shown.

2 Called “Surface-Initiated Cracks” (Soil Survey Division Staff, 

1993).

3 Called “Surface-Initiated Reversible Cracks” (Soil Survey Division 

Staff, 1993).

4 Called “Surface-Initiated Irreversible Cracks” (Soil Survey 

Division Staff, 1993).

5 Also called “Subsurface-Initiated Cracks” (Soil Survey Division 

Staff, 1993).

6 Called “Subsurface-Initiated Reversible Cracks” (Soil Survey 

Division Staff, 1993).
USDA-NRCS 2–77 September 2012

7 Called “Subsurface-Initiated Irreversible Cracks” (Soil Survey 

Division Staff, 1993).

Reversible Irreversible Reversible Irreversible

Crust-related Cracks Trans-horizon Cracks 

sand

soil

structure 

0.5 - 2 cm

0.1-0.5 cm

soil

structure 

CRACKS - DEPTH—Record the Average Apparent Depth (also 

called a “depth index value” in the Soil Survey Manual [Soil Survey 

Division Staff, 1993]), measured from the surface, as determined 

by the wire-insertion method (≈2 mm diameter wire). NOTE: This 

method commonly gives a standard but conservative measure of 

the actual fracture depth. Do not record this data element for cracks 

that are not open to the surface. Depth (and apparent vertical 

length) of subsurface cracks can be inferred from the Horizon Depth

column of layers exhibiting subsurface cracks.

CRACKS - RELATIVE FREQUENCY—Record the Average Number 

of Cracks, per meter, across the surface or Lateral Frequency

across a soil profile as determined with a line-intercept method. 

This data element cannot be assessed from cores or push tube 

samples.

SOIL CRUSTS (DISCUSSION)

C. Franks, R. Grossman, and P. Schoeneberger, NRCS, Lincoln, NE

A soil crust is a thin (i.e., <1 cm up to 10 cm thick) surface layer 

of soil particles bound together by living organisms and/or by 

minerals into a horizontal “mat” or small polygonal plates. Soil 

crusts form at the soil surface and have different physical and/or 

chemical characteristics than the underlying soil material. Typically, 

soil crusts change the infiltration rate of the mineral soil and 

stabilize loose soil particles and aggregates. There are two general 

categories of soil crusts: (I) biological crusts and (II) mineral crusts.

(I) Biological Crust (also called biotic, cryptogamic, microbiotic, 

or microphytic crust): a thin, biotically dominated surface layer or 
USDA-NRCS 2–78 September 2012

mat formed most commonly by cyanobacteria (blue green algae), 

green and brown algae, mosses, and/or lichens (NRCS, 1997; 

NRCS, 2001) that forms in or on the soil surface. Various types of 

microbiotic crusts have been recognized based on the biological 

communities of which they are composed (no prevailing consensus 

on types of biological crusts, at present).

(II) Mineral Crust (also called abiotic, nonbiotic, or nonmicrobiotic

crust): a thin surface layer composed of reversibly bonded soil 

particles or secondary mineral crystals, sometimes laminated, that 

is not physically dominated by a microbiotic “mat.”

1. Chemical Crust (e.g., salt incrustations): a thin surface layer 

that is dominated by macro- or microcrystalline evaporites of 

halite (NaCl), MgSO4, mirabilite (Na2SO4 • 10H2O), thenardite 

(Na2SO4), epsomite (MgSO4 • 7H2O), hexahydrite (MgSO4 • 

6H2O), bloedite (Na2Mg(SO4)2 • 4H2O), konyaite (Na2Mg(SO4)2

• 5H2O), loeweite (Na12Mg7 (SO4)13 • 15H2O), gypsum (CaSO4 • 

2H2O) (Singer and Warrington, 1992; Doner and Lynn, 1989), or 

other minerals. Other surficial mineral incrustations (e.g., from 

acid mine drainage or other sources) are included within this 

group.

2. Physical Crust: a physically reconstituted, reaggregated, or 

reorganized surface layer composed predominantly of primary 

mineral particles.

a). Raindrop Impact Crust (also called a structural crust): a 

thin layer that forms as a result of raindrop impact, which 

causes the clay in the soil to disperse, and subsequently 

hardens into a massive structureless or platy surface layer 

when it dries (Singer and Warrington, 1992).

b). Depositional Crust (also called a “fluventic zone”; Soil 

Survey Division Staff, 1993): a surface layer, commonly 

laminated and of variable thickness, consisting of small 

aggregates or primary mineral grains deposited by 

short-range runoff and subsequently dried (Singer and 

Warrington, 1992).

c). Freeze-Thaw Crust (Soil Survey Division Staff, 1993): a 

seasonal surface sediment layer 1 to 5 cm thick occurring 

on bare ground that has been disaggregated or puddled by 

radiant heating and cooling to produce freeze/thaw cycles 

while Very Moist or Wet. Commonly, the layer is composed 

of interlocking polygonal plates 5 to 20 cm in diameter, 

separated by cracks 1 to 2 cm wide that extend to the base 

of the crust and do not completely close upon wetting; Dry 

Rupture Resistance is ≤ Moderately Hard.

d). Vesicular Crust: a surface soil layer or zone characterized 

by spherical or ovoid, discontinuous pores 0.5 to 2 mm in 
USDA-NRCS 2–79 September 2012

diameter that are visible to the naked eye and make up a 

substantial portion of the matrix volume (i.e., ≥20% crosssectional area). These vesicles are believed to form when 

the pores between clay particles in platy soil structure are 

subjected to repeated wetting and drying. If soil aggregates 

become particularly unstable when they become saturated, 

air pressure may form small round voids (e.g., “bubbles”) 

that remain when the soil dries (Blackburn et al., 1975). 

Vesicular crusts occur primarily in arid and semiarid areas.

SOIL CRUSTS

Soil Crusts—Record the presence of any surface crust. No entry 

implies that no crust is present. (In NASIS, crusts are included 

under Pedoderm.)

Description—Soil crusts can be identified and recorded by Kind. 

Additional suggested descriptors may include: Rupture Resistance

(Surface Crusts and Plates), Porosity (Kind), Size, Diameter, 

Thickness, Amount (cross-sectional ground coverage), and Color.

SOIL CRUSTS - KIND—

Kind Code Criteria

BIOLOGICAL CRUSTS MC

biotically dominated surface 

“mat” of algae, lichens, 

mosses, etc.; also called biotic, 

cryptogamic, microbiotic, or 

microphytic crusts; slightly 

flexible when moist

MINERAL CRUSTS MI

reversibly bonded primary, 

secondary mineral grains; not 

biotically dominated; stiff or 

rigid when moist or dry

 Chemical Crusts CC evaporites (e.g., NaCl) or 

precipitates (e.g., CaCO3)

 Physical Crusts — reorganized, reconstituted

 raindrop impact

 crust RC dispersed, puddled, dried

 depositional crust DC sediments of variable thickness

 freeze-thaw crust FC bare ground, small polygons

 vesicular crust/

 zone VC

substantial discontinuous, 

spherical or ovoid pores; e.g., 

0.5 to 4 mm diameter
USDA-NRCS 2–80 September 2012

SPECIAL FEATURES

Record the Kind and Area (%) Occupied. Describe the special soil 

feature by kind and estimate the cross-sectional area (%) of the 

horizon that the feature occupies; e.g., lamellae, 15%.

SPECIAL FEATURES - KIND [Called Horizon Feature Kind in 

NASIS]—Identify the kind of special soil feature.

Kind Code 1 Criteria

desert 

pavement 2

DP A natural concentration of closely packed 

and polished stones at the soil surface in 

a desert (may or may not be an erosional 

lag).

water 

repellent 

layer

HL Either a surface or subsurface layer that 

repels water (e.g., dry organic materials; 

scorch layers in chaparral). See p. 7–14.

ice wedge 

cast

IC A vertical, often trans-horizon, wedgeshaped or irregular form caused by 

infilling of a cavity as an ice wedge melts; 

commonly stratified.

krotovinas KR Filled faunal burrows.

lamellae 3 LA Thin (e.g., >0.5 cm), pedogenically 

formed plates or intermittent layers.

lamina LN Thin (e.g., <1 cm), geogenically deposited 

strata or layers of alternating texture 

(e.g., silt and fine sand or silt and clay).

stone line SL A natural concentration of rock fragments 

caused by water erosion or transport 

erosional lag (i.e., carpedolith).

tongues 

of albic 

material

E Small areas or lobes of albic material that 

dip down (interfinger) more than 5 cm 

into nonalbic material.

tongues 

of argillic 

material

B Small areas or lobes of argillic material 

that dip down (interfinger) more than 

5 cm into nonargillic material.

1 Conventional codes consist of the entire name; e.g., Tongues of 

Albic Material. Consequently, no Conv. code is shown.

2 In NASIS, proposed to be moved to a new descriptor (data 

element) called Pedoderm (in NASIS 6.2) (Soil Survey Staff, 

2012b).

3 In NASIS, described under Diagnostic Horizon or Property - 

Kind.
USDA-NRCS 2–81 September 2012

SPECIAL FEATURES - AREA (%) OCCUPIED—Estimate the 

cross-sectional area (%) of the horizon that the feature occupies 

(see graphics, p. 7–1).

 SATURATED HYDRAULIC CONDUCTIVITY AND 

PERMEABILITY (DISCUSSION)

Saturated hydraulic conductivity (Ksat) is the single most 

scientifically valuable parameter for phenomena related to soilwater flow and transport. Ksat quantitatively defines a soil’s capacity 

to transmit water. Traditionally, NRCS (formerly SCS) used the term 

“permeability” for water-flow phenomena and used Permeability 

Classes (PC), which have prescribed percolation rate ranges 

(originally inches/hr). The PC and associated percolation rates are 

commonly mistaken to be Ksat. The confusion between Ksat, the 

term “permeability,” and the Permeability Classes arises for several 

reasons (Wysocki et al., 2002). A primary reason is that the term 

“permeability” has three meanings in soil science.

1) “Permeability” in a qualitative sense describes a soil’s 

capacity to transmit fluids, including water, or gases. No 

quantitative measure is implied. For example, sandy soils 

are more “permeable” than clayey soils.

2) “Permeability” (k) (Richards, 1952) (also known as intrinsic 

permeability) is an exclusive, quantitative porous material 

parameter controlled by pore geometry. In a stable porous 

material, (k) is independent of the fluid. Permeability (k) 

is the hydraulic conductivity (K) times the fluid viscosity 

(n) divided by the fluid density (ρ) and the gravitational 

constant (g) (Eq. 1). Permeability (k) has area units (e.g., 

m2). 

3) “Permeability” is short for permeability coefficient, which 

is hydraulic conductivity (K), or in saturated soil (Ksat). The 

Darcy equation quantitatively defines (Eq. 2) hydraulic 

conductivity (K) as the factor that relates flux (q) to the 

hydraulic gradient (∆h/l). Ksat depends upon both soil and 

fluid attributes. Measurement units for Ksat depend on the 

input units. With flux expressed as volume (cm3), head 

change (∆h) as cm (cm H2O/cm), and length as cm, the 

Ksat units are length/time (cm/s). Note that both variables 

q and K have units of length/time (cm/s), but they are 

distinctly different entities. Flux (q), when expressed as 

length/time, is an apparent rate that varies with ∆h/l. Ksat is 

a proportionality factor that relates q to ∆h/l. Ksat remains 

constant when the hydraulic gradient (∆h/l) varies. It is a 

physical parameter, not a rate.
USDA-NRCS 2–82 September 2012

Eq. 1 k = Kn/ρg

 k = permeability (cm2)

 K = hydraulic conductivity (cm/sec)

 n = fluid (water) viscosity (dyne-sec/cm)

 ρ = fluid (water) density (gm/cm3)

 g = gravitation acceleration (cm/sec2)

Eq. 2 q = V/At = -K(∆h/l)

 Darcy’s Equation (one dimensional flow) 

q = fluid flux (cm/s)

V = fluid volume (cm3)

 A = cross-sectional area (cm2)

 t = time (s)

 K = hydraulic conductivity (cm/s) 

∆h = change in hydraulic head (cm)

 l = length (cm)

The different permeability meanings have important distinctions 

that are not scientifically interchangeable. Most importantly, the 

intended meaning of “permeability” is not specifically discernible 

from written or verbal context alone. Meaning #1 carries no 

quantitative implications; meanings #2 and #3 have defined 

scientific applications. Uhland and O’Neal (1951) developed seven 

Permeability Classes (PC) from measurements on about 10,000 

3-inch cores collected from 900 sites. They chose the original 

PC ranges such that each class represented an equal number 

of measured values from the sample population (Mason et al., 

1957). Uhland and O’Neal (1951) measured discharge volume and 

calculated flux (q) as follows. 

Eq. 3 q = V/At 

V = fluid volume (in3)

 A = cross-sectional area (in2)

 t = time (hr)

Uhland and O’Neal (1951) specifically noted that the calculated 

value was a “percolation rate” with units of inches hr-1. These 

percolation rates defined the Permeability Class ranges. The Uhland 

and O’Neal study did not calculate Ksat from Darcy’s equation (Eq. 

2). The study method employed both a falling and constant head 

phase during measurement; the hydraulic gradient (∆h/l) varied 

and was undefined. Darcy’s equation requires a defined hydraulic 

gradient to solve for Ksat. The PC, therefore, are a set of soil 

“permeability” (meaning #1) classes arrayed by a method-specific 

percolation rate. To obtain an approximation of Ksat for the Uhland 

and O’Neal (1951) study, one can use the constant head hydraulic 

gradient (0.857 in) and the flux (V/At) as a general solution of 

Darcy’s equation, which yields V/At times 0.857=Ksat. This solution 

shows that PC percolation rates, at a minimum, exceed Ksat by 
USDA-NRCS 2–83 September 2012

about 15%. Two errors result if percolation rates are used as a 

proxy for Ksat. One is added uncertainty when estimating a soil Ksat. 

Do you decrease the estimate by 15%? Secondly, measured Ksat

values would not be equivalent to the PC percolation rates. Ksat is 

the scientific standard for soil-water flow calculations (Hillel, 1980), 

and there is great scientific merit in using Ksat over PC for soil-water 

flow interpretations.

Uhland and O’Neal (1951) also developed a set of field-observable 

properties to link the large number of unmeasured soils to a 

permeability class. The field properties included structure size and 

type, aggregate overlap, texture, pores, compaction, and clay 

mineralogy (O’Neal, 1952). NRCS soil scientists assigned soils 

to the permeability classes based on this characteristic set, or 

extrapolation from soils measured in the initial study. The original 

percolation rate ranges for the PC were altered (Soil Survey Staff, 

1971) and an eighth class added. The PC have historic merit and 

are retained for selected uses. 

To avoid the confounding difficulties inherent in the PC and the term 

“permeability,” the Soil Survey Division Staff (1993) developed Ksat

classes. To summarize:

1) Ksat and the percolation rates (that defined the Permeability 

Classes) are different physical parameters. Both Ksat and 

percolation rates are commonly expressed in units length/

time, which presents a false equivalency. 

2) Darcy’s equation relates Ksat to PC percolation rates. Core 

percolation rates used in Permeability Class development 

exceed Ksat by a minimum 15%. Ksat is not a rate.

3) No simple transformation exists to reliably convert PC 

percolation rates to Ksat. Soils with slower percolation rates 

have a greater difference between Ksat than those with more 

rapid percolation rates. 

4) To prevent confusion and avoid scientific inaccuracies, NRCS 

now emphasizes Ksat rather than the term “permeability” and 

Ksat classes rather than Permeability Classes.

SATURATED HYDRAULIC CONDUCTIVITY (KSAT)

Saturated hydraulic conductivity (Ksat) is the ease with which 

a saturated soil can transmit water through the pore space. Ksat is 

formally defined as the proportionality factor that relates water flow 

rate to the hydraulic gradient in Darcy’s equation (see Discussion). 

Ksat is a measurable soil property, or it may be estimated from 

other properties (texture, structure, bulk density, etc.). Direct field 

Ksat measurement is possible with various devices (Amoozemeter, 

Guelph Permeameter, double-ring infiltrometer). Multiple (e.g., 
USDA-NRCS 2–84 September 2012

≥5) measurement replications are needed on a horizon or layer to 

capture the natural variation. 

Record an estimated Ksat class or a measured Ksat value for each 

horizon/layer. If measured, record the Average Ksat, Standard 

Deviation, Replication Number (n), and Method. See NSSH, 

Exhibit 618.88 (Soil Survey Staff, 2012c) for guidelines for Ksat Class 

estimation using texture and bulk density (see p. 7–10).

Ksat

Class

NASIS 

Code 1

Criteria 2

μm/s cm/hr in/hr

Very Low # < 0.01 < 0.0036 < 0.001417Low # 0.01 to < 0.1 0.00360 to < 0.036 0.001417 to < 0.01417Mod. Low # 0.1 to < 1.0 0.0360 to < 0.360 0.01417 to < 0.1417Mod. High # 1.0 to < 10 0.360 to < 3.60 0.1417 to < 1.417High # 10 to < 100 3.60 to < 36.0 1.417 to < 14.17Very High # ≥ 100 ≥ 36.0 ≥ 14.17

1 For alternative units commonly used for these class boundaries (e.g., Standard 

International Units [Kg s/m3]), see the Soil Survey Manual (Soil Survey Division Staff, 1993, p. 107).

2 To convert μm/sec to in/hr, multiply μm/sec by 0.1417; e.g., (100 μm/sec) x 

(0.1417)=14.17 in/hr. To convert in/hr to μm/sec, multiply by 7.0572.
USDA-NRCS 2–85 September 2012

PERMEABILITY CLASSES

NRCS deemphasizes the use of Permeability Classes. Use Ksat. The 

Permeabilty Classes are listed here because of historic usage and 

because they are needed for selected soil interpretations.

Permeability 

Class Code Criteria: estimatedin/hr 1

Impermeable IM < 0.0015

Very Slow VS 0.0015 to < 0.06

Slow SL 0.06 to < 0.2

Moderately Slow MS 0.2 to < 0.6

Moderate MO 0.6 to < 2.0

Moderately Rapid MR 2.0 to < 6.0

Rapid RA 6.0 to < 20

Very Rapid VR ≥ 20

1 These class breaks were originally defined in English units 

and are retained here as no convenient metric equivalents are 

available.

CHEMICAL RESPONSE

Chemical response is the reaction of a soil sample to an applied 

chemical solution or a measured chemical value. Responses are 

used to identify the presence or absence of certain materials, to 

obtain a rough assessment of the amount present, to measure 

the intensity of a chemical parameter (e.g., pH), or to identify the 

presence of chemical species (e.g., Fe+2) in the soil.

REACTION (pH) - (Called Field_pH in NASIS)—Record pH and 

Method; record the pH value to the precision limit of the method 

(e.g., to the nearest tenth). The preferred method is pH meter for 

1:1 (water:soil). In NASIS, record pH numerical value and the 

method used (e.g., pH 6.5; 1:1 water:soil).

Descriptive Term Code 1 Criteria: pH range

Ultra Acid # <3.5

Extremely Acid # 3.5 to 4.4

Very Strongly Acid # 4.5 to 5.0

Strongly Acid # 5.1 to 5.5

Moderately Acid # 5.6 to 6.0

Slightly Acid # 6.1 to 6.5

Neutral # 6.6 to 7.3
USDA-NRCS 2–86 September 2012

Descriptive Term Code 1 Criteria: pH range

Slightly Alkaline # 7.4 to 7.8

Moderately Alkaline # 7.9 to 8.4

Strongly Alkaline # 8.5 to 9.0

Very Strongly Alkaline # >9.0

1 No codes; enter the measured value.

pH METHOD (called ph_determination_method in NASIS)—

Record the method used to measure pH.

pH Method 1 Code

INDICATOR SOLUTION 2 (pH range) 1

Bromocresol green 3.8 - 5.4 BG

Bromocresol purple 5.2 - 6.8 BP

Bromophenol blue 3.0 - 4.6 BL

Bromothymol blue 6.0 - 7.6 BB

Chlorophenol red 5.2 - 6.8 CHR

Cresol red 7.0 - 8.8 CR

Methyl red 4.8 - 6.0 MR

Phenol red 6.8 - 8.4 PR

Phenolphthalein 8.2 - 10.0 PT

Thymol blue 8.0 - 9.6 TB

COMMERCIAL COLORIMETRIC KITS

Hellige-Truog (kit) HT

Lamotte-Morgan (kit) LM

Soil Test (kit) ST

pH METER 2

pH meter 1:1 water 3 M11

pH meter 1:2 water (0.01 M CaCl2) 3 C12

pH meter 1N KCl M12

pH meter, saturated paste MSD

INDICATOR STRIPS 2

indicator paper strip 1N NaF 1 NF

pH indicator strip (unspecified) 2 STR

(H)ydrion (unspecified; = hydrogen ion paper strip) YD

pH unspecified 2, 3 PHU

1 Soil Survey Staff, 2009.

2 The pH method options in NASIS, release 6.2.

3 Preferred method.
USDA-NRCS 2–87 September 2012

EFFERVESCENCE—The gaseous response (seen as bubbles) of 

soil to applied HCl (carbonate test), H2O2 (MnO2 test), or other 

chemicals. Commonly, ≈1 N HCl is used for carbonate test. Apply 

the chemical to the soil matrix (for HCl, effervescence class refers 

only to the matrix; do not include carbonate masses, which are 

described separately as “Concentrations”). Record the observed 

response (Effervescence Class) and the Chemical Agent used. 

A complete example is: Strongly Effervescent with 1N HCl; or

ST, H2. (NOTE: In NASIS, manganese effervescence [by H2O2] is 

handled in separate tables; called MN_Effervescence_Agent and 

Mn_Effervescence classes; class codes and criteria are the same 

as those for Effervescence Class.)

Effervescence - Class—

Effervescence Class Code Criteria

Noneffervescent NE No bubbles form.

Very Slightly Effervescent VS Few bubbles form.

Slightly Effervescent SL Numerous bubbles form.

Strongly Effervescent ST Bubbles form a low foam.

Violently Effervescent VE Bubbles rapidly form a thick 

foam.

Effervescence - Location (obsolete in NASIS)—Use locations 

and codes from (Ped and Void) Surface Features - Location. 

(NOTE: The requirement to apply chemical agents [e.g., HCl] to the 

soil matrix makes many location choices invalid.)

Effervescence - Chemical Agent (In NASIS, the manganese 

chemical test agent [H2O2] is recorded in a separate table [mn_

effervescence_agent].)

Effervescence Agent Code Criteria

HCl (unspecified) 1 H1 Hydrochloric Acid:

Concentration Unknown

HCl (1N) 1, 2 H2 Hydrochloric Acid:

Concentration=1 Normal

HCl (3N) 1, 3 H3 Hydrochloric Acid:

Concentration=3 Normal

HCl (6N) 1, 4 H4 Hydrochloric Acid:

Concentration=6 Normal

H2O2 (unspecified) 5, 6 P1 Hydrogen Peroxide:

Concentration Unknown

H2O2 

5, 6 P2 Hydrogen Peroxide:

Concentration 3-4%
USDA-NRCS 2–88 September 2012

1 Positive reaction indicates presence of carbonates (e.g., CaCO3).

2 The only HCl concentration used for the effervescence field 

test. NOTE: A (1N HCl) solution is made by combining 1 part 

concentrated (37%) HCl (which is widely available) with 11 parts 

distilled H2O.

3 Use 3N HCl to determine the Calcium Carbonate Equivalent test. 

It is not used for Effervescence Class. An approximately 3N HCl 

solution (10% HCl or 2.87N) is made by combining 6 parts 37% 

HCl (which is widely available) with 19 parts distilled H2O.

4 A 6N HCl solution is used to distinguish between calcium and 

dolomitic carbonates. Dolomite reaction is slower and less 

robust than CaCO3 effervescence. A 6N HCl solution is made 

by combining 1 part concentrated (37%) HCl (which is widely 

available) with 1 part distilled H2O. Soil sample should be 

saturated in a spot plate and allowed to react for 1 to 2 minutes; 

froth=positive response. 

5 Rapid reaction indicates presence of manganese oxides (e.g., 

MnO2). Not used to determine “Effervescence Class.”

6 Under ambient conditions, Mn-oxides react rapidly whereas most 

organic matter reacts slowly with (3-4%) H2O2.

REDUCED CONDITIONS (called Reaction to alpha-dipyridyl in 

NASIS)—Record under “Notes” if evaluated.

Chemical 

Agent

Code Criteria

a,a-dipyridyl 1 P positive reaction 2: red or pink color 

develops

(0.2% conc. 3) N negative reaction: no color develops

1 Commonly stated as “alpha-alpha dipyridyl.”

2 Positive reaction indicates presence of Fe+2 (i.e., reduced 

conditions).

3 Childs, 1981.

Dipyridyl - Location—Describe the location(s) where the chemical 

test was conducted (use “Concentrations - Location” table); e.g., In 

the matrix (MAT).

SALINITY CLASS (DISCUSSION)—Soil salinity classes are based 

on electrical conductivity from a saturation paste extract. Gypsum 

(CaSO4 • 2H2O) and salts more soluble than gypsum (e.g., Na, Mg, 

and Ca chlorides and sulfates) are the sole or major contributors to 

the saturated paste extract EC.
USDA-NRCS 2–89 September 2012

NOTE: Electrical conductivity may be measured at various soil 

solution extract ratios (e.g., 1:1, 1:2, 1:5). The resultant EC 

values are not directly comparable because of the dilution effect. 

The salinity standard is the saturated paste extract EC. To avoid 

confusion, saturated paste EC is commonly denoted as ECe and 

other extracts denoted by the dilution ratio (e.g., EC1:1).

In addition to solution extracts, field measures of EC exist 

(e.g., electromagnetic induction [EMI], salinity probes). These 

measurements obtain an EC value that depends on salinity, 

moisture content, mineralogy, and texture. Such EC measurements 

are not directly comparable to ECe or EC of any extract ratio. For 

example, the electromagnetic induction (EMI) EC is known as 

apparent EC, which is denoted as ECa.

SALINITY CLASS—Estimate the Salinity Class. If the electrical 

conductivity is measured, record the EC Value (in the “Notes” 

column). Salinity class is based on saturated paste extract EC.

Salinity

Class

Code Saturated Paste - ECe

dS/m

Nonsaline 0 < 2

Very Slightly Saline 1 2 to < 4

Slightly Saline 2 4 to < 8

Moderately Saline 3 8 to < 16

Strongly Saline 4 ≥ 16

SODIUM ADSORPTION RATIO (SAR)—A measure of ion 

equilibrium between sodium (Na) in solution and exchangeable 

Na adsorbed on the soil (Soil Survey Staff, 2011). It is applied to 

soil solution extracts and irrigation waters. SAR=[Na+]/[([Ca+2] + 

[Mg+2])/2]0.5, where the cation concentration is in milliequivalents 

per liter. As a field method, it is commonly determined with soil 

paste and an electronic wand.
USDA-NRCS 2–90 September 2012

ODOR

ODOR—Record the Kind and relative Intensity of odor (by 

horizon) immediately after soil is exposed to air. The presence of 

an intense hydrogen sulfide odor (H2S; rotten egg) is commonly 

associated with a strongly anaerobic horizon where sulfate is 

reduced to sulfide (Fanning and Fanning, 1989).

Odor - Kind Code Criteria

None N No odor detected.

Petrochemical P Presence of gaseous or liquid gasoline, 

oil, creosote, etc.

Sulfurous S

Presence of H2S (hydrogen sulfide); 

“rotten egg”; commonly associated with 

strongly reduced soil containing sulfides.

Odor Intensity (proposed)—Estimate and record the relative 

intensity of any odor present.

Odor 

Intensity Code Criteria: relative intensity of odor

Slight SL Odor is faint (e.g., only detected when 

sample is brought close to nose).

Moderate MD

Odor is readily noticeable at arm’s length as 

one handles the material (e.g., intermediate 

intensity); only detected as one starts to dig 

into the material.

Strong ST

Odor is quite intense and readily detected 

before or immediately after the sample is 

exposed to air.

MISCELLANEOUS FIELD NOTES

Use additional descriptors and sketches to capture and convey 

information and features with no existing data element. Record as 

freehand notes under Miscellaneous Field Notes.

MINIMUM DATA SET (for a soil description)

Purpose, field logistics, habits, and soil materials all influence the 

specific properties necessary to “adequately” describe a given 

soil. However, some soil properties or features are so universally 

essential for interpretations or behavior prediction that they should 

always be recorded. These include: Location, Horizon, Horizon 
USDA-NRCS 2–91 September 2012

Depth, Horizon Boundary, Color, Redoximorphic Features, 

Texture, Structure, and Consistence.

PEDON DESCRIPTION DATA SHEET

Over the decades, field data for soils have been documented in 

various ways. For many years soil descriptions were made on small 

blue cards (SCS-SOI-232 form: USDA-SCS, various versions, dates, 

and locations of issuance). Since the NRCS reorganization in 1995, 

some MLRA Soil Survey Regional Offices (MOs) and other groups 

have generated informal, locally tailored data sheets.

The following (blank) data sheet is provided as an option to record 

basic soil description information. This revised data sheet contains 

the most widely used soil descriptors (e.g., depth, color). Other 

descriptors (called data elements in NASIS) should be added as 

needed in blank boxes or in the Miscellaneous Field Notes box or 

in the Notes column. See p. 2–93.

PEDON DESCRIPTION EXAMPLE

A completed profile description data sheet is included to 

demonstrate recording soil information in the field (see p. 2–95).

Most field descriptions will likely be entered into an electronic 

database by the describer or must be deciphered by other 

scientists. Therefore, descriptions should use reasonably mnemonic 

abbreviations, standard codes, or a combination of these or be 

written in “longhand” (using complete words). The following profile 

description contains examples of all of these conventions.

Soil descriptions in soil survey reports, Official Soil Series 

Descriptions (OSDs), or other NRCS products should follow 

prescribed formats and descriptor sequences (i.e., NSSH, Part 614; 

Soil Survey Staff, 2012c).

USDA-NRCS 2–93 September 2012

– 
USDA-NRCS 2–94 September 2012
USDA-NRCS 2–95 September 2012

– 
USDA-NRCS 2–96 September 2012
USDA-NRCS 2–97 September 2012

SUBAQUEOUS SOILS (SAS) DESCRIPTION

S. McVey, P.J. Schoeneberger, J. Turenne, M. Payne, and D.A. Wysocki, NRCS, 

and M. Stolt, URI

DISCUSSION: Permanently submerged mineral or organic 

substrates covered by relatively shallow water display recognizable 

soil morphology and meet Simonson’s soil formation (1959) model 

in that chemical and physical additions, losses, transformations, 

and translocations created the morphology. Such soils are 

informally known as “subaqueous soils.” Kubiena (1953) proposed 

a comprehensive classification that included subaqueous soils. More 

recently, Demas (1993, 1998) and Demas et al. (1996) reintroduced 

subaqueous soil concepts in the U.S. Recent reviews (Stolt and 

Rabenhorst, 2012; Soil Survey Staff, 2012d) provide comprehensive 

treatment of subaqueous soil settings and processes. Payne (2010) 

presents operational methods for subaqueous soil inventory. The 

11th edition of Keys to Soil Taxonomy (Soil Survey Staff, 2010) 

presently recognizes subaqueous soils as suborders of Entisols and 

Histosols (Wassents and Wassists) that meet the criterion of “a 

positive water potential at the soil surface for more than 21 hours of 

each day in all years.”

The description of subaqueous soils is similar to that of terrestrial 

soils but differs in several important ways. Many subaqueous soil 

parameters (color, texture, RMF, etc.) fit traditional descriptive 

conventions outlined in this Field Book. The unique setting and 

morphology of subaqueous soil coupled with its recent scientific 

import warrant a separate section that presents all descriptors in 

one place. This section includes description forms and subaqueous 

soil description examples. (NOTE: The most prevalent subaqueous 

settings are coastal marine or brackish estuarine. The descriptive 

conventions presented here reflect this. Freshwater subaqueous 

settings may require additional descriptors.)

SUBAQUEOUS SOILS DESCRIPTION—Record subaqueous soil 

profile information using the following parameters. (NOTE: Field 

Book soil descriptors presented elsewhere [e.g., horizon] have page 

number references. Please refer to the cited page for complete 

choice lists.)

BATHYMETRY

Bathymetry is the measurement of sea- or lake-floor or river 

bottom relief. Because of nautical importance, bathymetric data are 

commonly expressed as a depth from the water surface at Mean 

Lower Low Water (MLLW) tidal datum to the bottom. The water 

surface reference in a coastal setting is commonly Mean Low Water 

(MLW) or Mean Tide Level (MTL) (see graphic on p. 2–99). Lack of 

bathymetric data often requires field collection of such data during 
USDA-NRCS 2–98 September 2012

subaqueous soil survey. Protocols for bathymetric data collection 

are addressed elsewhere (Payne, 2010; Bradley and Payne, 2010).

The inverse of water depth is the subaqueous soil survey relief, 

which is useful for interpretation of subaqueous geoforms 

(landforms) and geomorphic description. Geomorphic description 

for subaqueous soils follows the same convention as those for 

terrestrial soils (p. 1–4). A compendium of subaqueous geoforms 

exists in the Geomorphic Description System (GDS) (Schoeneberger 

and Wysocki, 2012) (p. 3–38).

SITE

SITE/PEDON ID—Record the site/pedon identification number, 

such as the Soil Survey Site Identification Number (see p. 1–2). 

A complete example is S2011RI009014A. (Translation: This is a 

pedon sampled [S] for soil characterization during 2011 [2011], 

from Rhode Island [RI], in Washington County [009]; it is the 

fourteenth pedon [014] sampled in that county during 2011; and it 

is a satellite sample [A] related to the primary pedon.)

DATE—Record the date the sample was collected; e.g., MM, DD, 

YYYY.

TIME: START/END—Record the time that the pedon was opened 

(Start Time) and exposed to aerobic conditions for description and 

the time that the description was finished (End Time). (NOTE: First 

describe soil color and other soil properties that can change as a 

result of oxidation.)

DESCRIBER(S)—Record the people who describe the core; e.g., 

Herman Munster or HM.

WAYPOINT (Number)—Record the GPS waypoint number.

GPS (Model)—Record the GPS model used. (In NASIS, this is a text 

field.)

COORDINATES—Record the sample site GPS coordinates. 

(NOTE: For subaqueous soils, location is always obtained as a GPS 

coordinate.) 

GEODETIC DATUM—Record the Geodetic Datum (called GPS 

Datum in NASIS) used; e.g., WGS84.

ELEVATION—Elevation should be normalized relative to an 

appropriate vertical or tidal datum. In the U.S., use the North 

American Vertical Datum, 1988 (NAVD88). This elevation datum is 

the standard shown on recent USGS topographic maps. NOTE: For 

elevations below Mean Tidal Level (MTL), a minus sign precedes the 

numerical value (e.g., -1.2 m). For terrestrial anthropogenic water 
USDA-NRCS 2–99 September 2012

bodies (e.g., reservoir), the elevational reference (datum) is the 

design pool level.

TIDAL DATUM (DISCUSSION)—In a tidal system, a Tidal 

Datum is the elevation of the contact between open water and the 

land at a specified mean tidal level. A variety of tidal datums are 

commonly used (see Tidal Datums graphic). Mean Tide Level (MTL), 

formerly known as Mean Sea Level (MSL), is the average of all tidal 

fluctuation in a given area and represents the land-water interface 

on conventional topographic maps. It is also the datum to which 

terrestrial elevations are normalized. Mean High Water (MHW) and 

Mean Low Water (MLW) represent typical 24-hour tidal cycles. Mean 

Higher High Water (MHHW) and Mean Lower Low Water (MLLW) are 

based on lunar cycles that increase the amplitude of tides. Nautical 

charts used for boating are based on Mean Lower Low Water in an 

attempt to represent minimum water depths for navigation. Highest 

and Lowest Observed water depths are often related to severe 

storm events (e.g., storm surge) that exaggerate the typical tidal 

water depth. Specific vegetative communities are associated with 

the various tidal datums.

1 Stylized SAS upper limit: ≥21 hours submerged/day (Soil Survey 

Staff, 2010a, p. 123).
USDA-NRCS 2–100 September 2012

2 Tidal datum widely used on nautical maps for navigational 

context.

MAP UNIT—Record the map unit name or symbol in which the 

sample site occurs.

LOCATION DESCRIPTION—Record relevant geographic 

information (e.g., Greenwich Bay, Warwick, RI–southeastern 

shoreline, 1300 m SE of Sally Rock Point).

WATER DEPTH—Record water depth at observation time; e.g., 

120 cm.

BOTTOM TYPE—Record the dominant bottom type (used in 

combination with subaqueous vegetation type) at the sample site; 

e.g., sand.

Bottom Type 1 Criteria

Mud A silty, clayey, or organic bottom matrix.

Sand A sandy bottom matrix.

Shelly A bottom dominated by shells or shell 

fragments.

Stony or Bouldery A bottom sparsely covered by stones or 

boulders (0.01 to <0.1%).

Very Stony or

Very Bouldery

A bottom partially covered by stones or 

boulders (0.1 to <3%).

Extremely Stony or 

Extremely Bouldery

A bottom dominated by stones or boulders 

(3 to <15%).

Gravelly/Cobbly A bottom sparsely covered by gravel or 

cobbles (0.01 to <0.1%).

Very Gravelly/

Very Cobbly

A bottom partially covered by gravel or 

cobbles (0.1 to <3%).

Extremely Gravelly/

Extremely Cobbly

A bottom dominated by gravel or cobbles 

(3 to <15%).

Rubbly

A bottom substantially covered by large 

rock fragments of various sizes (15 to 

<50%).

Very Rubbly A bottom extensively covered by boulders

(>50%) 2.

1 These bottom types have been used in coastal SAS mapping. 

Other types exist and should be added as necessary. A formal 

ecologically based substrate array is found in the Coastal and 

Marine Ecological Classification Standard (Federal Geographic 

Data Committee, 2012).
USDA-NRCS 2–101 September 2012

2 If the surface rock fragments are >80%, the fragments are 

described as a distinct horizon and should be described as such 

(NSSH Amendment #4, 1998). 

SUBMERGED AQUATIC VEGETATION (SAV) (In NASIS, called 

Site Existing Vegetation table); e.g., ZOSTE [Zostera L.], 

eelgrass.—Record the Plant Symbol, Plant Common Name, and 

Plant Scientific Name of aquatic plants observed at the site (see 

p. 1–17). It is helpful to record the estimated percent cover for 

each major plant.

OBSERVATION METHOD—For each layer, describe the Kind of 

sampling device or procedure used to make observations of the site. 

Methods and tools for SAS are listed in the following table.

KIND (called Observation Method in NASIS)—

Kind Code Criteria: Tools and Methods

Bucket 

Auger BA Open, closed, sand, or mud buckets (5-12 cm diam.)

Dutch or 

Mud Auger DA

An open, strap-sided bucket auger 

(5-10 cm diam.) with a sharpened outer 

edge and a screw tip with a partial twist.

Dive DV A visual, onsite assessment performed 

under water.

Macaulay 

Sampler MS

A half-cylinder “gouge” sampler with 

a hinged door that’s pushed in and 

partially rotated to obtain a sample of soft 

sediments (e.g., organics).

Vibracore 

Tube VT A hollow tube (e.g., 4-8 cm diam.) vibrated into wet sands, silts, or organics.

Video VO Electronically recorded, photo or sequential 

digital images of a subaqueous setting/site.

(SOIL) DRAINAGE CLASS—Subaqueous soils have, by definition, 

a subaqueous (soil) Drainage Class (p. 1–11). There is a positive 

water potential at the soil surface for more than 21 hours of each 

day. The soils have a peraquic soil moisture regime (see 2012 Soil 

Survey Staff proposed revision to the Soil Survey Manual [Online at 

http://soils.usda.gov/technical/manual/proposedchanges.html]).
USDA-NRCS 2–102 September 2012

WATER COLUMN MEASUREMENTS

Water quality measurements are not required but are recommended 

to provide supplemental information on the specific aquatic 

environment in which the soil is found.

pH—Measure the pH (see p. 2–86) at two depths within the water 

column above the soil.

pH (#) Criteria

pH top Within 10 cm of the water surface.

pH bottom Within 10 cm of the bottom.

pH METHOD—Record the pH method used, as there can be 

considerable difference between methods (e.g., pH meter vs. pH 

indicator strip) (see p. 2–86).

Dissolved Oxygen or DO (mg/l)—Measure the dissolved oxygen 

(DO) at two depths within the water column above the soil.

Dissolved 

Oxygen (DO) (#) Criteria (mg/l)

DO top Within 10 cm of the water surface.

DO bottom Within 10 cm of the bottom.

SALINITY (ppt)—Measure the salinity; record in parts per 

thousand (ppt) at two depths within the water column above the 

soil. Measurement methods include handheld salinity meters and 

refractometers (e.g., YSI salinity meter, Vee Gee refractometer).

Salinity (#) Criteria

Salinity top Within 10 cm of the water surface.

Salinity bottom Within 10 cm of the bottom.

WATER TEMPERATURE—Record the water temperature at two 

depths within the water column above the soil.

Water Temperature (#) Criteria: Degrees

(Celsius [°C] or Fahrenheit [°F])

Water Temperature top Within 10 cm of the water surface.

Water Temperature bottom Within 10 cm of the bottom.
USDA-NRCS 2–103 September 2012

SOIL PROFILE MEASUREMENTS AND DESCRIPTION

HORIZON AND LAYER DESIGNATIONS—See p. 2–2.

HORIZON SUFFIXES FOR SUBAQUEOUS SOILS 

(DISCUSSION)—Amongst the conventional list of horizon 

subscripts (see Horizon Subscripts; p. 2–4), several suffixes are 

used extensively for subaqueous soils and warrant brief clarification:

g Strong gleying: The suffix g is used for soil horizons 

(including subaqueous soils) where Fe has been reduced and 

pedogenically removed, resulting in a chroma of 2 or less. 

(NOTE: Subaqueous soils are permanently submerged, and 

most are dominated by reduced conditions and subsequent 

gray colors, indicated by the use of the g suffix. The g is not 

applied to soil materials with gray colors attributed to the 

natural color of the geologic material from which they are 

derived [geogenic colors; e.g., gray shales].)

se Presence of sulfides: This symbol indicates the presence 

of sulfides in mineral or organic horizons. Horizons with sulfides 

typically have dark colors (e.g., value ≤4, chroma ≤2). 

DISCUSSION: An se horizon typically forms in coastal soil 

environments that are permanently saturated or submerged 

(e.g., low tidal marshes, lagoons, and some freshwater 

marshes or swamps). Soil materials in which sulfur reduction 

actively occurs release hydrogen sulfide gas (H2S), which is 

detectable by its distinctive odor (Fanning and Fanning, 1989; 

Fanning et al., 2002). (NOTE: Not all sulfide-bearing soil 

materials produce hydrogen sulfide gas. Sulfides may also 

occur in drier [oxidized] upland environments that have a 

geologic sulfide source. Examples include soils formed in parent 

materials derived from coal deposits [e.g., lignite] or soils that 

formed in coastal plain deposits [e.g., marcasite or pyrite] that 

have not been oxidized because of thick layers of overburden.)

LITHOLOGIC DISCONTINUITIES (DISCUSSION)—Describe the 

presence of any lithologic discontinuities (see p. 2–5; Numerical 

Prefixes; The Prime). Contrasting changes in parent material are 

indicated in Soil Horizon nomenclature by a sequential numeric 

prefix (e.g., A–Bw–2Bw–3C). (NOTE: The prefix “1” is implied 

and not shown by convention.) Discontinuities in subaqueous soils 

are described when there is a significant change in particle size or 

mineralogy that indicates the material was deposited by a different 

process. Important examples are a discontinuity at the change 

from material deposited in a marine environment to older material 

deposited on land and later inundated, or sand deposited over 

marsh organics. In contrast, deposits of similar particle size from 

multiple washover events on a washover-fan flat behind a barrier 
USDA-NRCS 2–104 September 2012

island would not be described as discontinuities (analogous to finely 

stratified alluvium). 

USE OF PRIMES—A prime (′) is used for horizons with identical 

characters that are separated by a horizon with different 

designations. The prime symbol (′), where appropriate, is placed 

after the master horizon designation and before the lowercase suffix 

letter symbols that follow it; e.g., B′t. In cases where three to five 

horizons have identical letter symbols, three to five prime symbols 

can be used for the other horizons (e.g., A, Cg, Aseb, Cseg1, Cseg2, 

A′seb, Cseb, A′′seb, C′seb).

HORIZON THICKNESS—See p. 2–6.

HORIZON BOUNDARY—Record HORIZON BOUNDARY 

DISTINCTNESS when possible (see p. 2–6). (NOTE: The 

HORIZON BOUNDARY TOPOGRAPHY cannot be adequately 

determined from small auger, push tube, or vibracore samples.)

ROCKS AND OTHER FRAGMENTS (Coarse Frags)—Describe 

the Kind, Size, and Quantity (% vol.), Roundness, etc., of rock 

and other coarse fragments in each horizon (see p. 2–46). Shell 

fragments > 2 mm are considered to be coarse fragments.

FIELD TEXTURE CLASS—Estimate the Field Texture Class by 

hand for each horizon (see p. 2–36).

SOIL COLOR—Record the Munsell color of the soil matrix (see 

p. 2–9). Include Color Condition as needed (e.g., reduced).

REACTION TO H2O2 (or Peroxide Color Change—see SAS 

Description Form) (In NASIS, called Reduced Monosulfide 

Presence)—Record the soil color response, as either yes (Y) or 

no (N), to the application of 3% H2O2 solution immediately after 

exposure to the air (e.g., a freshly broken ped or core interior). A 

positive reaction (color change) indicates the presence of reduced 

monosulfides (FeS), which quickly oxidize and change color upon 

application of hydrogen peroxide. “Peroxide Color Change” is an 

immediate (within 10 seconds), discernible color change upon 

addition of H2O2. (NOTE: This method is for monosulfide detection 

only and is not applicable to other sulfides [e.g., pyrite, marcasite, 

FeS2].)

Monosulfides, often in the form of Fe(II) monosulfides (FeS), are 

visible in reduced soil as a black color (e.g., 10YR 2/1 or N 2.5/0). 

When a sulfidic soil is oxidized, either in place due to oxidized 

water conditions or when the soil is drained or excavated and thus 

exposed to air (oxidized), Fe(ll) converts to Fe(III) and the typical 

black color is lost, leaving a gray or brown color (Lyle, 1983). An 

example of a common monosulfide oxidation reaction is:

4FeS + 9O2 + 10H2O = 4Fe(OH)3 +8H+ + 4SO4.
USDA-NRCS 2–105 September 2012

REACTION BY OXIDIZED pH (DISCUSSION) (Not a field 

test)—Oxidation of sulfides creates sulfuric acid as a byproduct 

that lowers pH. Monosulfidic materials are typically identified in the 

laboratory using an “oxidized pH” measurement (pH 1:1 water by 

pH meter), in which a soil undergoes aerobic incubation for at least 

16 weeks and the change in pH measurements are compared over 

time (especially initial vs. final). Sulfidic materials are indicated 

when 1) the initial pH >3.5 and 2) after oxidation the pH decreases 

by ≥0.5 unit to a value ≤4.0 within 16 weeks (or longer if the 

pH is still dropping after 16 weeks) until the pH reaches a nearly 

constant value. Exposure and oxidation of sulfidic materials (acid 

sulfate weathering) result in a sulfuric horizon via the formation of 

sulfuric acid. Field pH is initially measured either immediately after 

sampling or after thawing a frozen sample. Care should be taken 

to prevent oxidation of the sample prior to starting the aerobic 

incubation period and measurements. Hydrogen peroxide has also 

been used to determine the presence of reduced sulfides in soil 

samples with pH measurements made after complete oxidation with 

H2O2 (Finkelman and Giffin, 1986; Jennings et al., 1999). Hydrogen 

peroxide speeds up the natural oxidation reaction and can be 

represented in the following reaction as:

2FeS + 9H2O2 = 2Fe(OH)3 + 2SO4

2- + 4H+ + 4H2O. 

REACTION BY OXIDIZED pH (laboratory test)—Measure the 

pH over time; report the initial and final pH (after 16 weeks) and 

compare results for evidence of pH reduction over time. 

FLUIDITY CLASS—See p. 2–65, under Manner of Failure. Record 

the Fluidity class of each horizon/layer. (NOTE: Fluidity is estimated 

by squeezing a moist to wet palmful of soil and observing the extent 

to which the soil flows out between clenched fingers. Fluidity classes 

are based on the degree of “flow.” Soil bearing capacity decreases 

as fluidity increases.)

Fluidity 

Class Code Criteria

Nonfluid NF After full compression, no soil flows through 

the fingers.

Slightly 

Fluid SF

After full compression is exerted, some soil 

flows through fingers; most remains in the 

palm.

Moderately 

Fluid MF After full pressure is exerted, most soil flows through fingers; some remains in the palm.

Very Fluid VF

Under very gentle pressure, most soil flows 

through the fingers as a slightly viscous 

fluid; very little or no residue remains in the 

palm of the hand.
USDA-NRCS 2–106 September 2012

ODOR—Record the Kind and Intensity immediately after soil is 

exposed to air (see p. 2–90).

ORIGIN—Record the source of parent material from which the soil 

is derived (e.g., estuarine deposit).

NOTES—See Miscellaneous Field Notes (see p. 2–93). Describe 

supplemental information in the “Miscellaneous Field Notes” area or 

the “Notes” column on the description form. For example, describe 

the dominant plant fragment type and % (e.g., black needlerush 

fragments, 25%).

SALINITY (of Subaqueous Soils)

ELECTRICAL CONDUCTIVITY OF SUBAQUEOUS SOILS 

(DISCUSSION)—Salinity in terrestrial soils is evaluated by 

electrical conductivity (ds/m) of a saturated paste extract 

(Saturated Paste method, SSIR 51; Soil Survey Staff, 2009) or a 

given soil:water (by weight) ratio (e.g., 1:2, 1:5). The saturated 

paste EC is the standard salinity measure for terrestrial soils 

and is placed into Salinity Classes (see p. 2–89). Salinity is a 

crucial property of subaqueous soils and is also evaluated via EC 

measurement. The EC measurement, however, is conducted on a 

1:5 by volume soil:solution mixture (1:5 vol. method, SSIR 51; 

Soil Survey Staff, 2009). The resultant EC is not placed into the 

conventional (terrestrially focused) Salinity Classes.

Electrical conductivity of subaqueous soils is measured on 

samples that typically have been stored in a refrigerator or freezer 

immediately after sampling to prevent sulfide oxidation, which 

can influence the EC value. Terrestrial soil samples are dried prior 

to preparing a saturated paste extract. Subaqueous soils cannot 

be dried because of the sulfide oxidation potential. Hence, a 1:5 

volume method is used as follows: Measure 10 ml of moist sample; 

add 50 ml distilled water (5 times the soil volume). Stir the mixture 

briefly (10 seconds) and let settle (15 to 60 minutes). Electrical 

conductivity of the unfiltered supernatant is measured using a 

hand-held conductivity meter. 

Electrical Conductivity of SAS (1:5 vol method)—Measure 

and record the Electrical Conductivity (EC) in dS/m and record 

the Measurement Method used (e.g., 11.2 dS/m by hand-held 

electrical conductivity meter). 

SULFIDES (DISCUSSION)—Identifying the presence of sulfate is 

important to both pH and salinity (see Reaction by Oxidized pH). 

Oxidation of sulfides may generate salts that can alter salinity. 

BULK DENSITY SATIATED (DISCUSSION) (These are variations 

of the Soil Core Method. See Section 3.3.1.4 in SSIR 51, Soil Survey 

Staff, 2009)—It is generally not possible to collect subaqueous soil 
USDA-NRCS 2–107 September 2012

samples using the clod method for bulk density determination. 

Recommended alternative methods are: 

1) Collect a known volume at the field moisture state 

(satiated). Bulk density is then calculated based on the 

dried weight of a known volume of soil at the field moisture 

status.

Calculations (Soil Survey Staff, 2009)

Db = (ODW – RF – CW)/[CV – (RF/PD)], where:

Db = Bulk density of <2-mm fabric at sampled, field

 water state (g cm-3) 

ODW = Oven-dry weight 

RF = Weight of rock fragments 

CW = Empty core weight 

CV = Core volume 

PD = Density of rock fragments 

2) For vibracore samples (opened by cutting the sampling tube 

rather than by compressive extrusion), a 50-ml syringe with 

the end removed and shaped to fit the curved core is used 

as a mini-corer to extract a 10- to 30-ml volume sample. 

The cylinder is removed, extracting a sample of known 

volume. The sample is then analyzed following method 1 

(above). 

3) Samples collected in a peat sampler (e.g., Macaulay 

sampler) can be analyzed for bulk density following method 

2 if a known volume (e.g., a core segment) is collected and 

dried.

USDA-NRCS 2–109 September 2012
USDA-NRCS 2–110 September 2012
USDA-NRCS 2–111 September 2012

VIBRACORE SAMPLING FOR SUBAQUEOUS SOILS

Discussion

Subaqueous soils are challenging to observe and sample because 

of the positive pore pressure of free water in the soil and the water 

above the soil; therefore, a slightly different protocol for sampling 

them is helpful. Vibracore sampling is particularly well suited to 

obtain minimally disturbed samples from sandy, silty, or organic 

subaqueous materials lacking large or substantial coarse fragments. 

The principal concern is accounting for sample compression 

(compaction, repacking, or “core rot”), especially in material with 

Moderately Fluid or Very Fluid fluidity classes. (NOTE: A Vibracore 

Log Sheet [p. 2–113] must be paired with a Subaqueous Soil Profile 

Description [p. 2–109] or a conventional Soil Profile Description 

[p. 2–93].)

Site Description

Record subaqueous soil site information much the same as you 

record subaerial soil site information (see p. 1–1). Additional items 

to evaluate and describe include the following:

WATER DEPTH (UNIT)—Record the depth of water (and the units 

used) above the soil surface at the time the core is collected. (This 

information is used to develop/verify the map unit name; e.g., 

Billington silt loam, 0-1 m water depth.)

TIDAL PERIOD—Record the tidal period (incoming, high, 

outgoing, low, none) at the time of sample extraction. (NOTE: Most 

freshwater lakes do not exhibit appreciable tidal fluctuations.)

Core Descriptions

TOTAL PIPE LENGTH—Describe the total length of the collection 

pipe prior to coring. (This information is used as a check for depth 

of sample collection. The information may also be used to track how 

much pipe is consumed during a field season.)

RISER LENGTH—After insertion of the pipe tube, record the 

external length (cm) from the top of the collection pipe to the soil 

surface outside the pipe. 

INSIDE LENGTH—After insertion of the pipe tube, record the 

length (cm) from the top of the collection pipe to the soil surface 

inside the pipe. (NOTE: A sinker tied to a string and lowered to the 

soil surface inside the pipe facilitates measurement.)

CORE SETTLEMENT—Calculate the sample settlement/compaction 

(also called “rot”) by subtracting the Riser Length from the Inside 

Length. (NOTE: Settlement of the soil sample inside the pipe is 
USDA-NRCS 2–112 September 2012

common and difficult to precisely account for; therefore, vibracore 

samples only provide reasonable estimates of horizon depths.)

FINAL CORE LENGTH—Record the calculated length of the soil 

profile collected. (See graphic on Vibracore Log Sheet, p. 2–113.)

WHERE CORE IS STORED—Describe where the core is stored 

for future retrieval, description, and analysis (e.g., shed 2, core # 

2011-25). (NOTE: Subaqueous soils should be kept in refrigerated 

storage to slow chemical reactions, such as conversion of sulfides to 

sulfates, which influence pH or other soil properties.)
USDA-NRCS 2–113 September 2012

SITE

CORE LOG

Site/Pedon ID

Date/Time Sampled

Soil Type

Map Unit

Location 

Waypoint

GPS

Lat.

Lon.

UTM Easting

UTM Northing

UTM Zone

Elevation

Water Depth 

Tidal Period

a) TOTAL Pipe Length

b) RISER Length 

c) INSIDE Length

d) Core Settlement 

Final Core Length 

Where Is Core Stored?

Date Described

(YYYYSTFIPS###)

(geographic)

(#)

(model/unit #)

(NAVD 88)

(cm)

(before coring)

(after coring)

(sinker length: surface to bottom)

(= c - b)

(after core completed: = a - c)

S2011RI009014A

8/16/2011 8:30 AM

Frankensoil

Frankensoil mucky silt loam

Ninigret Pond: 1000 m E. of intersection of Route 1

and Route 1A at Ninigret Park, RI

4

Trimble Geo XH

721720 m

4583254 m

19

- 1.2 m

120 cm

Outgoing

390 cm

260 cm

264 cm

4 cm

126 cm

URI Bay Campus cold storage

8/17/2011

41 22' 13.0"

W 71 39' 4.0"

VIBRACORE LOG SHEET

Core Sketch

Water Surface

INSIDE Length

RISER Length

TOTAL Pipe Length

outside

soil surface

core

settlement,

compression
USDA-NRCS 2–114 September 2012
USDA-NRCS 2–115 September 2012

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USDA-NRCS 3–1 September 2012

GEOMORPHIC DESCRIPTION

GEOMORPHIC DESCRIPTION SYSTEM

(Version 4.2—03/01/2012)

P.J. Schoeneberger and D.A. Wysocki, NRCS, Lincoln, NE

PART I: PHYSIOGRAPHIC LOCATION

A) Physiographic Division

B) Physiographic Province

C) Physiographic Section

D) State Physiographic Area

E) Local Physiographic/Geographic Name

PART II: GEOMORPHIC DESCRIPTION

A) Landscape

B) Landform

C) Microfeature

D) Anthropogenic Features

PART III: SURFACE MORPHOMETRY

A) Elevation

B) Slope Aspect

C) Slope Gradient

D) Slope Complexity

E) Slope Shape

F) Hillslope—Profile Position

G) Geomorphic Component

1. Hills

2. Terraces, Stepped Landforms

3. Mountains

4. Flat Plains

H) Microrelief

I) Drainage Pattern

NOTE: Italicized NASIS shorthand codes, if available, follow each 

choice. Conventionally, the entire term is recorded.
USDA-NRCS 3–2 September 2012

PART I: PHYSIOGRAPHIC LOCATION

References for items A, B, and C: Physical Divisions of the United States 

(Fenneman, 1946); Physiographic Divisions of Alaska (Wahrhaftig, 1965).

Physiographic Divisions (A) Physiographic Provinces (B)

 Physiographic Sections (C)

Laurentian 

Upland

LU 1. Superior Upland SU

Atlantic Plain AP 2. Continental Shelf CS

3. Coastal Plain CP

 a. Embayed section EMS

b. Sea Island section SIS

c. Floridian section FLS

d. East Gulf Coastal plain EGC

 e. Mississippi alluvial valley MAV

f. West Gulf Coastal plain WGC

Appalachian AH 4. Piedmont Province PP

Highlands a. Piedmont upland PIU

 b. Piedmont lowlands PIL

5. Blue Ridge Province BR

 a. Northern section NOS

 b. Southern section SOS

6. Valley and Ridge Province VR

 a. Tennessee section TNS

 b. Middle section MIS

c. Hudson Valley HUV

7. St. Lawrence Valley SL

 a. Champlain section CHS

 b. St. Lawrence Valley,

 Northern section

NRS

8. Appalachian Plateau AP

 a. Mohawk section MOS

 b. Catskill section CAS

 c. Southern New York sect. SNY

 d. Allegheny Mountain sect. AMS

 e. Kanawaha section KAS

 f. Cumberland Plateau sect. CPS

 g. Cumberland Mtn. sect. CMS
USDA-NRCS 3–3 September 2012

Physiographic Divisions (A) Physiographic Provinces (B)

 Physiographic Sections (C)

9. New England Province NE

 a. Seaboard lowland sect. SLS

 b. New England upland sect. NEU

 c. White Mountain section WMS

d. Green Mountain section GMS

 e. Taconic section TAS

10. Adirondack Province AD

Interior Plains IN 11. Interior Low Plateaus IL

a. Highland rim section HRS

 b. Lexington lowland LEL

 c. Nashville basin NAB

 d. Possible western section WES

 (not delimited on map)

12. Central Lowland Province CL

 a. Eastern lake section ELS

 b. Western lake section WLS

 c. Wisconsin driftless section WDS

 d. Till plains TIP

 e. Dissected till plains DTP

f. Osage plain OSP

13. Great Plains Province GP

 a. Missouri plateau, glaciated MPG

 b. Missouri plateau,

 unglaciated

MPU

c. Black Hills BLH

d. High Plains HIP

 e. Plains Border PLB

 f. Colorado Piedmont COP

 g. Raton section RAS

 h. Pecos valley PEV

 i. Edwards Plateau EDP

 k. Central Texas section CTS

This division includes portions of Alaska

(see “Alaskan Physiographic Areas” section).

Interior IH 14. Ozark Plateau OP

Highlands a. Springfield-Salem plateaus SSP

 b. Boston “Mountains” BOM

15. Ouachita Province OU

 a. Arkansas Valley ARV

b. Ouachita Mountains OUM
USDA-NRCS 3–4 September 2012

Physiographic Divisions (A) Physiographic Provinces (B)

 Physiographic Sections (C)

Rocky RM 16. Southern Rocky Mountains SR

Mountain

System 17. Wyoming Basin WB

18. Middle Rocky Mountains MR

19. Northern Rocky Mountains NR

This division includes portions of Alaska

(see “Alaskan Physiographic Areas” section).

Intermontane IP 20. Columbia Plateau CR

Plateaus a. Walla Walla Plateau WWP

 b. Blue Mountain section BMS

 c. Payette section PAS

 d. Snake River Plain SRP

e. Harney section HAS

21. Colorado Plateau CO

a. High Plateaus of Utah HPU

 b. Uinta Basin UIB

 c. Canyon Lands CAL

 d. Navajo section NAS

e. Grand Canyon section GCS

 f. Datil section DAS

22. Basin and Range Province BP

a. Great Basin GRB

 b. Sonoran Desert SOD

 c. Salton Trough SAT

d. Mexican Highland MEH

 e. Sacramento section SAS

This division includes portions of Alaska

(see “Alaskan Physiographic Areas” section).

Pacific PM 23. Cascade-Sierra Mountains CM

Mountain a. Northern Cascade Mtns. NCM

 b. Middle Cascade Mtns. MCM

 c. Southern Cascade Mtns. SCM

 d. Sierra Nevada SIN

24. Pacific Border Province B

 a. Puget Trough PUT

b. Olympic Mountains OLM

c. Oregon Coast Range OCR
USDA-NRCS 3–5 September 2012

Physiographic Divisions (A) Physiographic Provinces (B)

 Physiographic Sections (C)

 d. Klamath Mountains KLM

 e. California Trough CAT

 f. California Coast Ranges CCR

 g. Los Angeles Ranges LAR

25. Lower California Province LC

This division includes portions of Alaska

(see “Alaskan Physiographic Areas” section).

Alaskan Physiographic Areas (Warhaftig, 1965)

The following Alaskan-Peninsula physiographic areas are 

extensions of the preceding North American Physiographic 

Divisions (e.g., Rocky Mountain System). These Alaskan 

extensions are presented separately rather than intermingled 

with the previous Division I Province lists because: a) they 

constitute a geographically coherent package (Wahrhaftig, 1965); 

b) these extensions were not contained within Fennman’s original 

work, which dealt only with the conterminous U.S. (Fenneman, 

1931, 1938, 1946); and c) Wahrhaftig’s map unit numbers are 

independent of, and inconsistent with, Fenneman’s. Wahrhaftig’s 

original map unit scheme and numbers are retained here for 

simplicity in using his map of the Alaskan peninsula. CAUTION:

Wahrhaftig’s map unit numbers should not be confused with 

similar map unit numbers from Fenneman’s map for the 

conterminous U.S.

Interior Plains IN 1. Arctic Coastal Plain Province —

a. Teshekpuk Hills section —

b. White Hills section —

2. Arctic Foothills Province AF

 a. Northern Section —

 b. Southern Section —

Rocky RM Arctic Mountains Province AM

Mountains 3. Delong Mountains section —

System 4. Noatak Lowlands section —

5. Baird Mountains section —

6. Central & E. Brooks Range

 sect.

—

7. Ambler-Chandalar Ridge &

 Lowland sect.

—

NOTE: The map unit numbering sequence shown here is from 

Wahrhaftig (1965) and is independent of, and not consistent with, 

that of Fenneman.
USDA-NRCS 3–6 September 2012

Physiographic Divisions (A) Physiographic Provinces (B)

 Physiographic Sections (C)

Intermontane IP Northern Plateaus Province —

Plateaus 8. Porcupine Plateau section —

 a. Thazzik Mountain

9. Old Crow Plain section (noted

 but not described)

—

10. Olgivie Mountains section —

11. Tintina Valley (Eagle Trough)

 sect.

—

12. Yukon-Tanana Upland section —

 a. Western Part

 b. Eastern Part

13. Northway-Tanacross Lowland

 sect.

—

14. Yukon Flats section —

15. Rampart Trough section —

16. Kokrine-Hodzana Highlands

 sect.

—

 a. Ray Mountains

 b. Kokrine Mountains

Western Alaska Province —

17. Kanuti Flats section —

18. Tozitna-Melozitna Lowland

 sect.

—

19. Indian River Upland section —

20. Pah River Section —

a. Lockwood Hills

b. Pah River Flats

c. Zane Hills

 d. Purcell Mountains

21. Koyukuk Flats section —

22. Kobuk-Selawik Lowland sect. —

 a. Waring Mountains

23. Selawik Hills section —

24. Buckland River Lowland sect. —

25. Nulato Hills section —

26. Tanana-Kuskowin Lowland

 sect.

—

27. Nowitna Lowland section —

28. Kuskokwim Mountains section —

29. Innoko Lowlands section —

30. Nushagak-Big River Hills sect. —

31. Holitna Lowland section —

32. Nushagak-Bristol Bay Lowland 

 sect.

—
USDA-NRCS 3–7 September 2012

Physiographic Divisions (A) Physiographic Provinces (B)

 Physiographic Sections (C)

33. Seward Peninsula Province SEP

 a. Bendeleben Mountains

 b. Kigluaik Mountains

 c. York Mountains

Bering Shelf Province BES

34. Yukon-Kuskokwim Coastal

 Lowland sect.

—

 a. Norton Bay Lowland

35. Bering Platform section —

a. St. Lawrence Island

b. Pribilof Island

c. St. Matthew Island

d. Nunivak Island

36. Ahklun Mountains Province —

NOTE: The map unit numbering sequence shown here is from 

Wahrhaftig (1965) and is independent of, and not consistent with, 

that of Fenneman.

Pacific PM Alaska-Aleutian Province AAC

Mountain 37. Aleutian Islands section —

System 38. Aleutian Range section —

39. Alaska Range (Southern Part)

 sect.

—

40. Alaska Range (Central &

 Eastern Parts) section

—

 a. Mentasta-Nutzotin Mtn.

 segment

41. Northern Foothills of the

 Alaska Range section

—

Coastal Trough Province —

42. Cook Inlet-Susitna Lowland

 sect.

—

43. Broad Pass Depression section —

44. Talkeetna Mountains section —

 a. Chulitna Mountains

b. Fog Lakes Upland

 c. Central Talkeetna

 Mountains

 d. Clarence Lake Upland

 e. Southeastern Talkeetna

 Mountains

45. Upper Matanuska Valley sect. —

46. Clearwater Mountains section —
USDA-NRCS 3–8 September 2012

Physiographic Divisions (A) Physiographic Provinces (B)

 Physiographic Sections (C)

47. Gulkana Upland section —

48. Copper River Lowland section —

 a. Eastern Part

 b. Western Part: Lake Louis

 Plateau

49. Wrangell Mountains section —

50. Duke Depression (not described)

51. Chatham Trough section —

52. Kupreanof Lowland section —

Pacific Border Ranges Province PBS

53. Kodiak Mountains section —

54. Kenai-Chugach Mtns. sect. —

55. St Elias Mountains section —

a. Fairweather Range subsection

56. Gulf of Alaska Coastal section —

57. Chilkat-Baranof Mtns. section —

 a. Alsek Ranges subsection

b. Glacier Bay subsection

c. Chichagof Highland subsection

 d. Baranof Mountains subsection

58. Prince of Wales Mtns. sect. —

Coast Mountains Province COM

59. Boundary Pass section —

60. Coastal Foothills section —

Other Physiographic Areas

(not addressed by Fenneman, 1946, or Wahrhaftig, 1965)

Pacific Rim PR Pacific Islands Province PI

a. Hawaiian Islands HAI

b. Guam GUM

c. Trust Territories * 

 (e.g., Commonwealth of the 

Northern Mariana Islands, 

Federated States of

 Micronesia, Palau, Republic of

Marshall Islands, American

 Samoa, etc.)

TRT

d. Other

* Most of the former U.S. Trust Territories of the Pacific are now 

independent nations. This designation is used here solely for 

brevity and to aid in accessing archived historical data.
USDA-NRCS 3–9 September 2012

Physiographic Divisions (A) Physiographic Provinces (B)

 Physiographic Sections (C)

Caribbean CB Caribbean Islands Province CI

Basin a. Greater Antilles (Puerto Rico, 

Cuba, Hispaniola, Jamaica)

GRA

b. Lesser Antilles (U.S. Virgin

Islands, Barbados, Grenada, 

 Martinique, etc.)

LEA

c. Other

Undesignated UN Other OT

(reserved for temporary or international designations)

STATE PHYSIOGRAPHIC AREA (D)

e.g., Des Moines Lobe (IA)

(OPTIONAL) (Entries presently undefined; to be 

developed in conjunction with each 

State Geological Survey; target 

scale is approximately 1:100,000.)

LOCAL PHYSIOGRAPHIC/GEOGRAPHIC NAME (E)

e.g., Pilot’s Knob (IA)

(OPTIONAL) (Entries presently undefined; to 

be developed in conjunction with 

each State Geological Survey; 

may include area names found 

on USGS 7.5- and 15-minute 

topographic maps; target scale is 

approximately 1:24,000.)
USDA-NRCS 3–10 September 2012

PART II: GEOMORPHIC DESCRIPTION (OUTLINE)

I) COMPREHENSIVE LISTS: Alphabetical rosters of all terms 

currently recognized in a given category.

 A) LANDSCAPES

 B) LANDFORMS

 C) MICROFEATURES

 D) ANTHROPOGENIC FEATURES

II) GEOMORPHIC ENVIRONMENTS and OTHER GROUPINGS:

Landscape, landform, and microfeature terms grouped by 

geomorphic process (e.g., Fluvial) or by common settings (e.g., 

Water Bodies). These lists are not mutually exclusive; some 

features occur in more than one environment or setting (e.g., 

hill).

1. Coastal Marine and Estuarine} GEOMORPHIC 

ENVIRONMENTS

2. Lacustrine

3. Fluvial

4. Solution

5. Eolian

6. Glacial

7. Periglacial

8. Mass Movement

9. Volcanic and Hydrothermal

10. Tectonic and Structural

11. Slope } OTHER

GROUPINGS

12. Erosional

13. Depressional

14. Wetlands

15. Water Bodies

16. Subaqueous Features
USDA-NRCS 3–11 September 2012

PART II: GEOMORPHIC DESCRIPTION

Codes: Conventionally, the entire land-feature term is used (e.g., 

dune field). Some data storage programs (e.g., NASIS) may 

have shorthand codes developed for some terms. If available, an 

italicized code follows each term (e.g., meander belt MB); these are 

shown for historical purposes.

I) COMPREHENSIVE LISTS:

 A) LANDSCAPES (broad assemblages or unique groups of 

natural, spatially associated features). (LF=Landform;

w=water body)

alluvial plain AP

alluvial plain remnant AR

badlands BA

bajada (also LF) BJ

barrier island (also LF) BI

basin BS

basin floor (also LF) BC

batholith BL

bay [coast] (w; also LF) BY

bolson BO

breached anticline (also LF) BD

breaklands BR

breaks (also LF) BK

caldera (also LF) CD

canyonlands CL

coastal plain (also LF) CP

cockpit karst CPK

cone karst CK

continental glacier CG

delta plain (also LF) DP

dissected breaklands DB

dissected plateau DI

drumlin field DF

dune field (also LF) DU

estuary (w; also LF) ES

everglades EG

fan piedmont (also LF) FP

fault-block mountains FM

fluviokarst FK

fluviomarine terrace (also 

LF)

FT

fold-thrust hills FTH

foothills FH

glaciokarst GK

gulf (w; also LF) GU

hills (singular=LF) HI

ice-margin complex IC

intermontane basin (also 

LF)

IB

island (also LF) IS

karst KR

kegel karst KK

lagoon (w; also LF) LG

lake plain (also LF) LP

lava field (also LF) LF

lava plain (also LF) LV

lava plateau (also LF) LL

lowland LW

marine terrace (also LF) MT

meander belt MB

mountain range MR

mountains (singular=LF) MO

mountain system MS

ocean (w) OC

outwash plain (also LF) OP

peninsula PE

piedmont PI

piedmont slope PS

plain (singular=LF) PL

plateau (also LF) PT

rift valley RF

river valley (also LF) RV
USDA-NRCS 3–12 September 2012

sand plain SP

sandhills SH

scabland SC

sea (w; also LF) SEA

semi-bolson SB

shield volcano (also LF) SV

shore complex (also LF) SX

sinkhole karst SK

sound (w; also LF) SO

strait (w; also LF) ST

tableland TB

thermokarst TK

till plain (also LF) TP

tower karst TW

upland UP

valley (also LF) VA

volcanic field (also LF) VF

 B) LANDFORMS (discrete, natural, individual earthsurface features mappable at common survey scales). 

(LS=Landscape; Micro=Microfeature; w=water body. 

Italicized NASIS code follows each term.)

aa lava flow ALF

alas AA

alluvial cone AC

alluvial fan AF

alluvial flat AP

alpine glacier AG

anticline AN

arete AR

arroyo AY

ash field AQ

ash flow AS

atoll AT

avalanche chute AL

axial stream AX

back-barrier beach BBB

back-barrier flat BBF

backshore AZ

backswamp BS

bajada (also LS) BJ

ballena BL

ballon BV

bar BR

barchan dune BQ

barrier beach BB

barrier beach [relict] BBR

barrier cove BAC

barrier flat BF

barrier island (also LS) BI

basin floor (also LS) BC

basin-floor remnant BD

bay [coast] (w; also LS) BAY

bay [geom.] BYG

bay bottom BOT

bayou (w) WC

beach BE

beach plain BP

beach ridge BG

beach terrace BT

berm BM

beveled base BVB

blind valley VB

block field BW

block glide BLG

block lava flow BLF

block stream BX

blowout BY

bluff BN

bog BO

box canyon BOX

braided stream BZ

breached anticline (also LS) BRL

breaks (also LS) BK

broad interstream divide BID

butte BU

caldera (also LS) CD

canyon CA
USDA-NRCS 3–13 September 2012

canyon bench CYB

canyon wall CW

Carolina Bay CB

channel (also Micro) CC

chenier CG

chenier plain CH

cinder cone CI

cirque CQ

cirque floor CFL

cirque headwall CHW

cirque platform CPF

cliff CJ

climbing dune CDU

closed depression

(also Micro)

CLD

coastal plain (also LS) CP

cockpit COC

col CL

collapse sinkhole CSH

collapsed ice-floored 

lakebed

CK

collapsed ice-walled lakebed CN

collapsed lake plain CS

collapsed outwash plain CT

colluvial apron COA

complex landslide CLS

coral island COR

coulee CE

cove CO

cove [water] (w) COW

crag and tail CAT

creep CRE

crevasse filling CF

cuesta CU

cuesta valley CUV

cutoff CV

debris avalanche DA

debris fall DEF

debris flow DF

debris slide DS

debris spread DES

debris topple DET

deflation basin DB

deflation flat DFL

delta DE

delta plain (also LS) DC

depression DP

diapir DD

diatreme DT

dike DK

dip slope DL

disintegration moraine DM

distributary DIS

divide DN

dome DO

drainageway DQ

drainhead complex DRC

draw DW

drumlin DR

drumlinoid ridge DRR

dune DU

dune field (also LS) DUF

dune lake (w) DUL

dune slack (also Micro) DUS

earthflow EF

earth spread ESP

earth topple ETO

end moraine EM

ephemeral stream (also 

Micro)

EPS

eroded fan remnant EFR

eroded fan-remnant 

sideslope

EFS

erosion remnant ER

escarpment ES

esker EK

estuary (w; also LS) WD

faceted spur FS

fall FB

falling dune FDU

fan FC

fan apron FA

fan collar FCO

fanhead trench FF

fan piedmont (also LS) FG

fan remnant FH
USDA-NRCS 3–14 September 2012

fan skirt FI

fault block FAB

fault-line scarp FK

fault zone FAZ

fen FN

fissure vent FIV

fjord (w) FJ

flat FL

flatwoods FLW

flood plain FP

flood-plain playa FY

flood-plain splay FM

flood-plain step FO

flood-tidal delta FTD

flood-tidal delta flat FTF

flood-tidal delta slope FTS

flow FLO

flute (also Micro) FU

fluviomarine bottom FMB

fluviomarine terrace (also 

LS)

FMT

fold FQ

foredune FD

fosse FV

free face (also Geom. 

Component—Hills, 

Mountains)

FW

fringe-tidal marsh FTM

gap GA

geyser GE

geyser basin GEB

geyser cone GEC

giant ripple GC

glacial drainage channel GD

glacial lake (w) WE

glacial lake [relict] GL

glacial-valley floor GVF

glacial-valley wall GVW

glacier GLA

gorge GO

graben GR

ground moraine GM

gulch GT

gulf (w; also LS) GU

gut [channel]; (w; also 

Micro)

WH

gut [valley] GV

half graben HG

hanging valley HV

headland HE

head-of-outwash HD

headwall HW

high hill HH

highmoor bog HB

hill (plural=LS) HI

hillslope HS

hogback HO

homoclinal ridge HCR

homocline HC

horn HR

horst HT

hot spring HP

ice-contact slope ICS

ice-marginal stream IMS

ice pressure ridge IPR

ice-pushed ridge IPU

inlet IL

inselberg IN

inset fan IF

interdrumlin IDR

interdune (also Micro) ID

interfluve (also Geom. 

Component—Hills)

IV

interior valley INV

intermittent stream (also 

Micro)

INT

intermontane basin (also 

LS)

IB

island (also LS) IS

kame KA

kame moraine KM

kame terrace KT

karst cone KC

karstic marine terrace KMT

karst lake KAL

karst tower KTO
USDA-NRCS 3–15 September 2012

karst valley KVA

kettle KE

kipuka KIP

knob KN

knoll KL

lagoon (w; also LS) WI

lagoon bottom LBO

lagoon channel LCH

lagoon [relict] LAR

lahar LA

lake (w) WJ

lakebed (w) LB

lakebed [relict] LBR

lake plain (also LS) LP

lakeshore LF

lake terrace LT

landslide LK

lateral moraine LM

lateral spread LS

lava dome LD

lava field (also LS) LFI

lava flow LC

lava flow unit (also Micro) LFU

lava plain (also LS) LN

lava plateau (also LS) LL

lava trench (also Micro) LTR

lava tube LTU

ledge LE

levee LV

loess bluff LO

loess hill LQ

longitudinal dune LDU

longshore bar LON

longshore bar [relict] LR

louderback LU

low hill LH

lowmoor bog LX

maar MAA

mainland cove MAC

main scarp (also Micro) MAS

mangrove swamp MAN

marine lake (w) ML

marine terrace (also LS) MT

marsh MA

mawae MAW

meander MB

meandering channel MC

meander scar MS

meander scroll MG

medial moraine MH

mesa ME

meteorite crater MEC

mogote MOG

monadnock MD

monocline MJ

moraine MU

mountain (plural=LS) MM

mountain slope MN

mountain valley MV

mudflow MW

mud pot MP

muskeg MX

natural levee NL

nearshore zone NZ

nearshore zone [relict] NZR

notch NO

nunatak NU

open depression (also 

Micro)

ODE

outwash delta OD

outwash fan OF

outwash plain (also LS) OP

outwash terrace OT

overflow stream channel OSC

oxbow OX

oxbow lake (w) WK

paha PA

pahoehoe lava flow PAF

paleoterrace PTR

parabolic dune PB

parna dune PD

partial ballena PF

patterned ground PG

pavement karst PAV
USDA-NRCS 3–16 September 2012

peak PK

peat plateau PJ

pediment PE

perennial stream (w; also 

Micro)

PS

pillow lava flow PIF

pingo PI

pinnacle (also Micro) PIN

pitted outwash plain PM

pitted outwash terrace POT

plain (plural=LS) PN

plateau (also LS) PT

playa PL

playa dune (also Micro) PDU

playa floor (also Micro) PFL

playa lake (w) WL

playa rim (also Micro) PRI

playa slope (also Micro) PSL

playa step (also Micro) PST

plug dome PP

pluvial lake (w) PLL

pluvial lake [relict] PQ

pocosin PO

point bar PR

point bar [coastal] PRC

pothole (also Micro) PH

pothole lake (w) WN

proglacial lake (w) WO

proglacial lake [relict] PGL

pyroclastic flow PCF

pyroclastic surge PCS

raised beach RA

raised bog RB

ravine RV

recessional moraine RM

reef RF

ribbed fen RG

ridge RI

rim RJ

rise (also Micro) (also 

Geom. Component—Flat 

Plains)

RIS

river (w) RIV

river valley (also LS) RVV

roche moutonnée (also 

Micro)

RN

rockfall (also Micro) ROF

rockfall avalanche RFA

rock glacier RO

rock pediment ROP

rock spread ROS

rock topple ROT

rotational debris slide RDS

rotational earth slide RES

rotational rock slide RRS

rotational slide RTS

sabkha SAB

saddle SA

sag (also Micro) SAG

sag pond (w; also Micro) SGP

salt marsh SM

salt pond (w; also Micro) WQ

sand flow (also Micro) RW

sand ramp SAR

sand sheet RX

scarp RY

scarp slope RS

scree slope SCS

sea (w; also LS) SEA

sea cliff RZ

seep (also Micro) SEE

seif dune SD

semi-open depression SOD

shield volcano (also LS) SHV

shoal (w) WR

shoal [relict] SE

shore SHO

shore complex (also LS) SHC

sill RT

sinkhole SH

slackwater (w) WS

slickrock (also Micro) SLK

slide SJ

slot canyon SLC

slough (w) SL
USDA-NRCS 3–17 September 2012

slump block SN

snowfield SNF

soil fall SOF

solution platform SOP

solution sinkhole SOS

sound (w; also LS) SO

spit SP

spur SQ

stack [coast] SRC

stack [geom.] SR

star dune SDU

steptoe ST

stock STK

stoss and lee SAL

strait (w; also LS) STT

strand plain SS

strath terrace SU

stratovolcano SV

stream (w) STR

stream terrace SX

strike valley STV

string bog SY

structural bench SB

submerged back-barrier 

beach

SBB

submerged mainland beach SMB

submerged point bar 

[coast]

SPB

submerged–upland tidal 

marsh

STM

submerged wave-built 

terrace

SWT

submerged wave-cut 

platform

SWP

swale (also Micro) SC

swallow hole TB

swamp SW

syncline SZ

talus cone TC

talus slope TAS

tarn (w; also Micro) TAR

terminal moraine TA

terrace TE

terrace remnant TER

thermokarst depression 

(also Micro)

TK

thermokarst lake (w) WV

tidal flat TF

tidal inlet TI

tidal inlet [relict] (w) TIR

tidal marsh TM

till-floored lake plain TLP

till plain (also LS) TP

toe (also Micro) TOE

tombolo TO

topple TOP

tor TQ

Toreva block TOR

translational debris slide TDS

translational earth slide TES

translational rock slide TRS

translational slide TS

transverse dune TD

trough TR

tunnel valley TV

tunnel-valley lake (w) TVL

underfit stream US

U-shaped valley UV

valley (also LS) VA

valley-border surfaces VBS

valley flat VF

valley floor VL

valley-floor remnant VFR

valley side VS

valley train VT

volcanic cone VC

volcanic crater CR

volcanic dome VD

volcanic field (also LS) VOF

volcanic neck VON

volcanic pressure ridge 

(also Micro)

PU

volcano VO

V-shaped valley VV

wash WA

washover fan WF
USDA-NRCS 3–18 September 2012

washover-fan flat WFF

washover-fan slope WFS

water-lain moraine WM

wave-built terrace WT

wave-cut platform WP

wave-worked till plain WW

wind gap WG

window WIN

wind-tidal flat WTF

yardang (also Micro) YD

yardang trough (also Micro) YDT

 C) MICROFEATURES (discrete, natural earth-surface 

features typically too small to delineate at common survey 

scales).

 1) Common Microfeatures (not used in association with

the landform “patterned ground”).

bar BA

channel (also LF) CH

closed depression (also LF) CD

corda CO

cutter CU

dune slack (also LF) DS

dune traces DT

earth pillar EP

ephemeral stream (also LF) ES

finger ridge FR

flute (also LF) FL

frost boil FB

glacial groove GG

groove GR

gully GU

gut [channel] (w; also LF) WH

hillock HI

hoodoo HO

ice wedge IWD

ice wedge cast IWC

interdune (also LF) ID

intermittent stream (w; 

also LF)

INT

karren KA

lava flow unit (also LF) LFU

lava trench (also LF) LT

main scarp (also LF) MAS

minor scarp MIS

mound MO

nivation hollow NH

open depression (also LF) OP

perennial stream (w; also 

LF)

PS

pinnacle (also LF) PI

playa dune (also LF) PD

playa floor (also LF) PF

playa rim (also LF) PR

playa slope (also LF) PSL

playa step (also LF) PST

playette PL

pond (w) PON

pool (w) POO

pothole (also LF) PH

rib RB

rill RL

ripple mark RM

rise (also LF) (also Geom. 

Component—Flat Plains)

RIS

rockfall (also LF) ROF

roche moutonnée (also LF) POC

sag (also LF) SAG

sag pond (w; also LF) SP

salt pond (w; also LF) WQ

sand boil SB

sand flow (also LF) RW

seep (also LF) SE

shoreline SH

shrub-coppice dune SCD

slickrock (also LF) SLK

slip face SF
USDA-NRCS 3–19 September 2012

solifluction lobe SOL

solifluction sheet SS

solifluction terrace ST

solution chimney SCH

solution corridor SCO

solution fissure SOF

solution pipe SOP

spatter cone SPC

spiracle SPI

strandline SL

swale (also LF) SW

swash zone SZ

tank (w) TA

tarn (w; also LF) TN

terracettes TER

thermokarst depression 

(also LF)

TK

toe [mass mvt.] (also LF) TOE

tree-tip mound TTM

tree-tip pit TTP

tumulus (pl.: tumuli) TU

vernal pool (seasonal water) VP

volcanic pressure ridge 

(also LF)

VPR

yardang (also LF) YD

yardang trough (also LF) YDT

zibar ZB

 2) Periglacial “patterned ground” Microfeatures

(Singular forms [e.g., circle] are used for a single 

feature [pedon scale], whereas plural forms [e.g., 

circles] are used for map unit components.)

circle CI

earth hummock EH

high-center polygon HCP

ice wedge polygon IWP

low-center polygon LCP

nonsorted circle NSC

palsa (=peat hummock) PA

polygon PYG

sorted circle SCI

stripe STR

turf hummock TH

 3) Other “patterned ground” Microfeatures (Singular 

forms [e.g., hummock] are used for a single feature 

[pedon scale], whereas plural forms [e.g., hummocks] 

are used for map unit components.)

bar and channel BC

circular gilgai CG

elliptical gilgai EG

gilgai GI

hummock HU

linear gilgai LG

mima mound MM

pimple mound PM

puff PU
USDA-NRCS 3–20 September 2012

 D) ANTHROPOGENIC FEATURES (discrete, artificial 

[human-made] earth-surface features).

anthroscape ANT

artificial collapsed 

depression

ACD

artificial levee AL

beveled cut BC

bioswale BS

borrow pit BP

burial mound BM

conservation terrace 

(modern)

CT

cut (e.g., railroad) CUT

cutbank CB

ditch DI

double-bedding mound 

(i.e., bedding mound used 

for timber; lower Coastal 

Plain)

DBM

drainage ditch DD

dredge-deposit shoal DDS

dredge spoil bank DSB

dredged channel DC

dump DU

fill FI

filled marshland FM

floodway FW

furrow FR

gravel pit GP

headwall (anthro) HW

hillslope terrace (ancient) HT

impact crater IC

interfurrow IF

landfill (see sanitary landfill) —

leveled land LVL

log landing LL

midden MI

openpit mine OM

polder POL

pond (human-made) PO

quarry QU

railroad bed RRB

reclaimed land RL

rice paddy RP

road bed RB

road cut RC

sand pit SP

sanitary landfill SL

scalped area SA

sewage lagoon SWL

skid trail ST

spoil bank SB

spoil pile SPP

surface mine SM

tillage mound TM

truncated soil TS
USDA-NRCS 3–21 September 2012

II) GEOMORPHIC ENVIRONMENTS and OTHER GROUPINGS:

Landscape, landform, and microfeature terms grouped 

by geomorphic process (e.g., Fluvial) or by common 

setting (e.g., Water Body). LS=Landscape; LF=Landform; 

Micro=Microfeature. Lists are not mutually exclusive.

 1. COASTAL MARINE and ESTUARINE (wave or tidal 

control or near-shore/shallow marine).

Landscapes:

barrier island (also LF) BI

bay [coast] (w; also LF) BY

coastal plain (also LF) CP

delta plain (also LF) DP

estuary (w; also LF) ES

fluviomarine terrace (also 

LF)

FT

gulf (w; also LF) GU

island (also LF) IS

lagoon (w; also LF) LG

lowland LW

marine terrace (also LF) MT

ocean (w) OC

peninsula PE

sea (w; also LF) SEA

shore complex SX

sound (w; also LF) SO

strait (w; also LF) ST

Landforms:

atoll AT

back-barrier beach BBB

back-barrier flat BBF

backshore AZ

bar BR

barrier beach BB

barrier cove BAC

barrier flat BF

barrier island (also LS) BI

bay [coast] (w; also LS) BAY

bay bottom BOT

beach BE

beach plain BP

beach ridge BG

beach terrace BT

berm BM

bluff BN

chenier CG

chenier plain CH

coastal plain (also LS) CP

coral island COR

cove [water] (w) COW

delta DE

delta plain (also LS) DC

drainhead complex DRC

estuary (also LS) WD

flat FL

flatwoods FLW

fluviomarine terrace (also 

LS)

FMT

foredune FD

fringe-tidal marsh FTM

gulf (w; also LS) GU

gut [channel] (w, also 

Micro)

WH

headland HE

island (also LS) IS

lagoon (w; also LS) WI

lagoon [relict] LAR

longshore bar LON

longshore bar [relict] LR

mangrove swamp MAN

marine lake (w) ML

marine terrace (also LS) MT

nearshore NZ
USDA-NRCS 3–22 September 2012

nearshore zone [relict] NZR

point bar [coastal] PRC

raised beach RA

reef RF

sabkha SAB

salt marsh SM

sea (w; also LS) SEA

sea cliff RZ

semi-open depression SOD

shoal [relict] SE

shore SHO

shore complex (also LS) SHC

sound (w; also LS) SO

spit SP

stack [coast] SRC

strait (w; also LS) STT

strand plain SS

submerged–upland tidal 

marsh

STM

tidal flat TF

tidal inlet TI

tidal inlet [relict] TIR

tidal marsh TM

tombolo TO

washover fan WF

wave-built terrace WT

wave-cut platform WP

wind-tidal flat WTF

Microfeatures:

gut [channel] (w; also LF) WH

ripple mark RM

shoreline SH

swash zone SZ
USDA-NRCS 3–23 September 2012

 2. LACUSTRINE (related to inland water bodies).

Landscapes:

bay [coast] (w; also LF) BY

delta plain (also LF) DP

island (also LF) IS

lake plain (also LF) LP

peninsula PE

shore complex (also LF) SX

Landforms:

backshore AZ

bar (also Micro) BR

barrier beach BB

barrier flat BF

barrier island BI

bay [coast] (w; also LS) BAY

beach BE

beach plain BP

beach ridge BG

beach terrace BT

berm BM

bluff BN

delta DE

delta plain (also LS) DC

flat FL

flood-plain playa FY

foredune FD

headland HE

island (also LS) IS

karst lake KAL

lagoon WI

lagoon [relict] LAR

lake (w) WJ

lakebed [relict] LBR

lake plain (also LS) LP

lakeshore LF

lake terrace LT

longshore bar LON

longshore bar [relict] LR

nearshore zone NZ

nearshore zone [relict] NZR

oxbow lake WK

playa PL

playa floor (also Micro) PFL

playa lake (w) WL

playa rim (also Micro) PRI

playa slope (also Micro) PSL

playa step (also Micro) PST

pluvial lake (w) PLL

pluvial lake [relict] PQ

raised beach RA

sabkha SAB

salt marsh SM

shoal [relict] SE

shore SHO

shore complex (also LS) SHC

spit SP

stack [coast] SRC

strand plain SS

till-floored lake plain TLP

tombolo TO

water-lain moraine WM

wave-built terrace WT

wave-cut platform WP

wave-worked till plain WW

Microfeatures:

bar (also LF) BA

playa floor (also LF) PF

playa rim (also LF) PR

playa slope (also LF) PSL

playa step (also LF) PST

playette PL

ripple mark RM

shoreline SH

strandline SL

swash zone SZ

vernal pool VP
USDA-NRCS 3–24 September 2012

 3. FLUVIAL (dominantly related to concentrated water flow 

[channel flow]; includes both erosional and depositional 

features with the exceptions of glaciofluvial landforms 

[see Glacial] and permanent water features [see Water 

Bodies]).

Landscapes:

alluvial plain AP

alluvial plain remnant AR

badlands BA

bajada (also LF) BJ

breaklands BR

breaks BK

canyonlands CL

delta plain (also LF) DP

dissected breaklands DB

fan piedmont FP

meander belt MB

river valley (also LF) RV

scabland SC

Landforms:

alluvial cone AC

alluvial fan AF

alluvial flat AP

arroyo AY

axial stream (w) AX

backswamp BS

bajada (also LS) BJ

bar (also Micro) BR

basin-floor remnant BD

block stream BX

box canyon BOX

braided stream BZ

canyon CA

channel CC

coulee CE

cutoff CV

delta DE

delta plain (also LS) DC

drainageway DQ

drainhead complex DRC

draw DW

ephemeral stream (also 

Micro)

EPS

fan apron FA

fan collar FCO

fanhead trench FF

fan remnant FH

fan skirt FI

flood plain FP

flood-plain playa FY

flood-plain splay FM

flood-plain step FO

giant ripple GC

gorge GO

gulch GT

gut [valley] GV

inset fan IF

intermittent stream (also 

Micro)

INT

levee LV

meandering channel MC

meander scar MS

meander scroll MG

natural levee NL

overflow stream channel OSC

oxbow OX

paleoterrace PTR

point bar PR

ravine RV

river valley (also LS) RVV

semi-open depression SOD

slot canyon SLC

strath terrace SU

stream terrace SX
USDA-NRCS 3–25 September 2012

terrace remnant TER

valley flat VF

valley-border surfaces VBS

valley-floor remnant VFR

wash WA

wind gap WG

Microfeatures:

bar (also LF) BA

bar and channel (patterned 

ground)

BC

channel CH

ephemeral stream (also LF) ES

groove GR

gully GU

intermittent stream (also 

LF)

INT

ripple mark RM

swash zone SZ

 4. SOLUTION (dominated by dissolution and, commonly, 

subsurface drainage).

Landscapes:

cockpit karst CPK

cone karst CK

fluviokarst FK

glaciokarst GK

karst KR

kegel karst KK

sinkhole karst SK

thermokarst TK

tower karst TW

Landforms:

blind valley VB

cockpit COC

collapse sinkhole CSH

interior valley INV

karst cone KC

karstic marine terrace KMT

karst lake (w) KAL

karst tower KTO

karst valley KVA

mogote MOG

pavement karst PAV

pinnacle PIN

sinkhole SH

solution platform SOP

solution sinkhole SOS

swallow hole TB

thermokarst depression 

(also Micro)

TK

yardang (also Micro) YD

yardang trough (also Micro) YDT

Microfeatures:

cutter CU

karren KA

solution chimney SCH

solution corridor SCO

solution fissure SOF

solution pipe SOP

thermokarst depression 

(also LF)

TK

yardang (also LF) YD

yardang trough (also LF) YDT
USDA-NRCS 3–26 September 2012

 5. EOLIAN (dominantly wind related; erosion or deposition).

Landscapes:

dune field (also LF) DU

sandhills SH

sand plain SP

Landforms:

barchan dune BQ

blowout BY

climbing dune CDU

deflation basin DB

deflation flat DFL

dune DU

dune field (also LS) DUF

dune lake (w) DUL

dune slack (also Micro) DUS

falling dune FDU

foredune FD

interdune (also Micro) ID

loess bluff LO

loess hill LQ

longitudinal dune LDU

paha PA

parabolic dune PB

parna dune PD

playa dune (also Micro) PDU

sabkha SAB

sand ramp SAR

sand sheet RX

seif dune SD

slickrock (also Micro) SLK

star dune SDU

transverse dune TD

yardang (also Micro) YD

yardang trough (also Micro) YDT

Microfeatures:

dune slack (also LF) DS

dune traces DT

interdune (also LF) ID

playa dune (also LF) PD

playette PL

shrub-coppice dune SCD

slickrock (also LF) SLK

slip face SF

yardang (also LF) YD

yardang trough (also LF) YDT

zibar ZB

 6. GLACIAL (directly related to glaciers; includes 

glaciofluvial, glaciolacustrine, glaciomarine, and outwash 

features).

Landscapes:

continental glacier CG

drumlin field DF

glaciokarst GK

hills HI

ice-margin complex IC

outwash plain (also LF) OP

till plain (also LF) TP
USDA-NRCS 3–27 September 2012

Landforms:

alpine glacier AG

arete AR

cirque CQ

cirque floor CFL

cirque headwall CHW

cirque platform CPF

col CL

collapsed ice-floored 

lakebed

CK

collapsed ice-walled lakebed CN

collapsed lake plain CS

collapsed outwash plain CT

crag and tail CAT

crevasse filling CF

disintegration moraine DM

drumlin DR

drumlinoid ridge DRR

end moraine EM

esker EK

fjord (w) FJ

flute (also Micro) FU

fosse FV

giant ripple GC

glacial drainage channel GD

glacial lake (w) WE

glacial lake [relict] GL

glacial-valley floor GVF

glacial-valley wall GVW

glacier GLA

ground moraine GM

hanging valley HV

head-of-outwash HD

ice-contact slope ICS

ice-marginal stream IMS

ice pressure ridge IPR

ice-pushed ridge IPU

interdrumlin IDR

kame KA

kame moraine KM

kame terrace KT

kettle KE

lateral moraine LM

medial moraine MH

moraine MU

nearshore zone NZ

nearshore zone [relict] NZR

nunatak NU

outwash delta OD

outwash fan OF

outwash plain (also LS) OP

outwash terrace OT

paha PA

pitted outwash plain PM

pitted outwash terrace POT

pothole (also Micro) PH

pothole lake (intermittent 

water)

WN

proglacial lake (w) WO

proglacial lake [relict] PGL

recessional moraine RM

roche moutonnée (also 

Micro)

RN

rock glacier RO

snowfield SNF

stoss and lee SAL

swale (also Micro) SC

tarn (w; also Micro) TAR

terminal moraine TA

till-floored lake plain TLP

till plain (also LS) TP

tunnel valley TV

tunnel-valley lake (w) TVL

underfit stream US

U-shaped valley UV

valley train VT

water-lain moraine WM

wave-worked till plain WW
USDA-NRCS 3–28 September 2012

Microfeatures:

flute (also LF) FL

glacial groove GG

ice wedge IWD

ice wedge cast IWC

nivation hollow NH

pothole (also LF) PH

roche moutonnée (also LF) POC

swale (also LF) SW

tarn (w; also LF) TN

 7. PERIGLACIAL (related to nonglacial, cold climate [modern 

or relict], including periglacial forms of patterned ground. 

NOTE: Consider “patterned ground” as a landform, but 

treat specific types of patterned ground [singular or plural] 

as microfeatures).

Landscapes:

coastal plain CP

hills HI

plains PL

thermokarst TK

Landforms:

alas AA

block field BW

muskeg MX

patterned ground (see 

Microfeatures below for 

types)

PG

peat plateau PJ

pingo PI

rock glacier RO

string bog SY

thermokarst depression 

(also Micro)

TK

thermokarst lake (w) WV

Microfeatures:

circle CI

earth hummock EH

frost boil FB

high-center polygon HCP

ice wedge IWD

ice wedge cast IWC

ice-wedge polygon IWP

low-center polygon LCP

nivation hollow NH

nonsorted circle NSC

palsa (=peat hummock) PA

polygon PYG

solifluction lobe SOL

solifluction sheet SS

solifluction terrace ST

sorted circle SCI

stripe STR

thermokarst depression 

(also LF)

TK

turf hummock TH
USDA-NRCS 3–29 September 2012

 8. MASS MOVEMENT (=MASS WASTING) (dominated by 

gravity, including creep forms; also see “Mass Movement 

Types” table, p. 5–8).

Landscapes: These generic landscapes are not mass movement 

features per se but are commonly modified by and include localized 

areas of mass movement.

breaklands BR

dissected breaklands DB

foothills FH

hills HI

mountain range MR

mountains MO

Landforms:

ash flow AS

avalanche chute AL

block glide BLG

block stream BX

colluvial apron COA

complex landslide CLS

creep CRE

debris avalanche DA

debris fall DEF

debris flow DF

debris slide DS

debris spread DES

debris topple DET

earthflow EF

earth spread ESP

earth topple ETO

fall FB

flow FLO

lahar LA

landslide LK

lateral spread LS

main scarp (also Micro) MAS

mudflow MW

rockfall (also Micro) ROF

rockfall avalanche RFA

rock glacier RO

rock spread ROS

rock topple ROT

rotational debris slide RDS

rotational earth slide RES

rotational rock slide RRS

rotational slide RTS

sag (also Micro) SAG

sag pond (w; also Micro) SGP

sand flow RW

scree slope SCS

slide SJ

slump block SN

soil fall SOF

talus cone TC

talus slope TAS

toe (also Micro) TOE

topple TOP

Toreva block TOR

translational debris slide TDS

translational earth slide TES

translational rock slide TRS

translational slide TS

Microfeatures:

main scarp (also LF) MAS

minor scarp MIS

rockfall (also LF) ROF

sag (also LF) SAG

sag pond (w; also LF) SP

sand boil SB

solifluction lobe SOL

solifluction sheet SS

solifluction terrace ST

terracettes TER

toe (also LF) TOE
USDA-NRCS 3–30 September 2012

 9. VOLCANIC and HYDROTHERMAL

Landscapes:

caldera (also LF) CD

foothills FH

hills HI

lava field (also LF) LF

lava plain (also LF) LV

lava plateau (also LF) LL

mountains MO

shield volcano (also LF) SV

volcanic field (also LF) VF

Landforms:

aa lava flow ALF

ash field AQ

ash flow AS

block lava flow BLF

caldera (also LS) CD

cinder cone CI

diatreme DT

dike DK

fissure vent FIV

geyser GE

geyser basin GEB

geyser cone GEC

hot spring HP

kipuka KIP

lahar LA

lava dome LD

lava field (also LS) LFI

lava flow LC

lava flow unit (also Micro) LFU

lava plain (also LS) LN

lava plateau (also LS) LL

lava trench (also Micro) LTR

lava tube LTU

louderback LU

maar MAA

mawae MAW

mud pot MP

pahoehoe lava flow PAF

pillow lava flow PIF

plug dome PP

pyroclastic flow PCF

pyroclastic surge PCS

shield volcano (also LS) SHV

steptoe ST

stratovolcano SV

volcanic cone VC

volcanic crater CR

volcanic dome VD

volcanic field (also LS) VOF

volcanic neck VON

volcanic pressure ridge 

(also Micro)

PU

volcano VO

Microfeatures:

corda CO

lava flow unit (also LF) LFU

lava trench (also LF) LT

spatter cone SPC

spiracle SPI

tumulus (pl.: tumuli) TU

volcanic pressure ridge 

(also LF)

VPR
USDA-NRCS 3–31 September 2012

 10. TECTONIC and STRUCTURAL (related to regional or local 

bedrock structures or crustal movement; recognized only if 

expressed at or near the land surface).

Landscapes:

basin floor BC

batholith BL

bolson BO

breached anticline (also LF) BD

dissected plateau DP

fault-block mountains FM

fold-thrust hills FTH

foothills FH

hills HI

intermontane basin IB

mountain range MR

mountains MO

mountain system MS

piedmont slope PS

plateau PT

rift valley RF

semi-bolson SB

tableland TB

valley VA

Landforms:

anticline AN

breached anticline (also LS) BRL

canyon bench CYB

cuesta CU

cuesta valley CUV

diapir DD

dike DK

dip slope DL

dome DO

fault block FAB

fault-line scarp FK

fault zone FAZ

fold FQ

graben GR

half graben HG

hogback HO

homoclinal ridge HCR

homocline HC

horst HT

louderback LU

meteorite crater MEC

monocline MJ

rock pediment ROP

scarp slope RS

sill RT

stock STK

strike valley STV

structural bench SB

syncline SZ

window WIN

Microfeatures:

sand boil SB
USDA-NRCS 3–32 September 2012

 11. SLOPE (generic terms [e.g., hill] or those that describe 

slope form, geometry, or arrangement of land features 

rather than any particular genesis or process).

Landscapes:

badlands BA

breached anticline (also LF) BD

breaklands BR

breaks BK

canyonlands CL

dissected breaklands DB

dissected plateau DI

fault-block mountains FM

foothills FH

hills (singular=LF) HI

mountain range MR

mountains MO

mountain system MS

piedmont PI

piedmont slope PS

plains (singular=LF) PL

plateau (also LF) PT

tableland TB

upland UP

Landforms:

beveled base BVB

block stream BX

bluff BN

breached anticline (also LS) BRL

broad interstream divide BID

butte BU

canyon bench CYB

canyon wall CW

cliff CJ

colluvial apron COA

cuesta CU

dip slope DL

dome DO

escarpment ES

faceted spur FS

fault block FAB

fault-line scarp FK

free face (also Geom. 

Component—Hills, 

Mountains)

FW

gap GA

headwall HW

high hill HH

hill (plural=LS) HI

hillslope HS

hogback HO

interfluve (also Geom. 

Component—Hills)

IV

knob KN

knoll KL

ledge LE

low hill LH

mesa ME

mountain (plural=LS) MM

mountain slope MN

mountain valley MV

notch NO

paha PA

peak PK

pediment PE

plain (plural=LS) PN

plateau (also LS) PT

ridge RI

rim RJ

rise (also Micro) (also 

Geom. Component—Flat 

Plains)

RIS

rock pediment ROP

scarp RY

scarp slope RS

scree slope SCS

slickrock (also Micro) SLK
USDA-NRCS 3–33 September 2012

spur SQ

stack [geom.] SR

structural bench SB

talus cone TC

talus slope TAS

tor TQ

valley VA

valley-floor remnant VFR

wind gap WG

Microfeatures:

finger ridge FR

mound MO

rib RB

rill RL

rise (also LF) (also Geom. 

Component—Flat Plains)

RIS

slickrock (also LF) SLK
USDA-NRCS 3–34 September 2012

 12. EROSIONAL (related dominantly to water erosion but 

excludes perennial, concentrated channel flow [i.e. fluvial, 

glaciofluvial] or eolian erosion).

Landscapes:

badlands BA

breached anticline (also LF) BD

breaklands BR

breaks BK

canyonlands CL

dissected breaklands DB

dissected plateau DI

foothills FH

hills HI

mountain range MR

mountains MO

piedmont PI

piedmont slope PS

plateau (also LF) PT

tableland TB

Landforms:

ballena BL

ballon BV

basin floor remnant BD

beveled base BVB

breached anticline (also LS) BRL

canyon bench CYB

canyon wall CW

col CL

colluvial apron COA

cuesta CU

cuesta valley CUV

eroded fan remnant EFR

eroded fan-remnant 

sideslope

EFS

erosion remnant ER

free face (also Geom. 

Component—Hills, 

Mountains)

FW

gap GA

hogback HO

inselberg IN

monadnock MD

notch NO

paha PA

partial ballena PF

peak PK

pediment PE

plateau (also LS) PT

rock pediment ROP

sabkha SAB

saddle SA

scarp slope RS

slickrock (also Micro) SLK

stack [geom.] SR

strike valley STV

structural bench SB

terrace remnant TER

tor TQ

valley-border surfaces VBS

valley-floor remnant VFR

wind gap WG

window WIN

Microfeatures:

earth pillar EP

finger ridge FR

groove GR

gully GU

hoodoo HO

pinnacle PI

rib RB

rill RL

slickrock (also LF) SLK

swale SW
USDA-NRCS 3–35 September 2012

 13. DEPRESSIONAL (low areas or declivity features, excluding 

permanent water bodies).

Landscapes:

basin BS

basin floor (also LF) BC

bolson BO

breached anticline (also LF) BD

breaklands BR

dissected breaklands DB

semi-bolson SB

valley VA

Landforms:

alluvial flat AP

basin floor (also LS) BC

basin floor remnant BD

box canyon BOX

breached anticline (also LS) BRL

canyon CA

canyon wall CW

Carolina Bay CB

closed depression (also 

Micro)

CLD

col CL

coulee CE

cove CO

cuesta valley CUV

depression DP

drainageway DQ

drainhead complex DRC

gap GA

gorge GO

gulch GT

gut [valley] GV

intermontane basin IB

kettle KE

mountain valley MV

open depression (also 

Micro)

ODE

playa PL

playa floor (also Micro) PFL

playa rim (also Micro) PRI

playa slope (also Micro) PSL

playa step (also Micro) PST

pothole (also Micro) PH

pothole lake (intermittent 

water)

WN

ravine RV

sabkha SAB

saddle SA

sag (also Micro) SAG

semi-open depression SOD

slot canyon SLC

strike valley STV

swale (also Micro) SC

trough TR

U-shaped valley UV

valley VA

valley floor VL

V-shaped valley VV

Microfeatures:

closed depression (also LF) CD

open depression (also LF) OP

playa floor (also LF) PF

playa rim (also LF) PR

playa slope (also LF) PSL

playa step (also LF) PST

playette PL

pothole (also LF) PH

sag (also LF) SAG

semi-open depression SOD

swale (also LF) SW

tree-tip pit TTP
USDA-NRCS 3–36 September 2012

 14. WETLANDS (related to vegetated and/or shallow water 

areas and wet soils). (Provisional list: conventional, 

geologic definitions; not legalistic or regulatory usage.)

Landscapes:

estuary (also LF) ES everglades EG

Landforms:

alas AA

backswamp BS

bog BO

Carolina Bay CB

dune slack (also Micro) DUS

ephemeral stream (also 

Micro)

EPS

estuary (also LS) WD

fen FN

flood-plain playa FY

fringe-tidal marsh FTM

highmoor bog HB

intermittent stream (also 

Micro)

INT

lowmoor bog LX

mangrove swamp MAN

marsh MA

muskeg MX

oxbow lake (ephemeral 

water)

WK

peat plateau PJ

playa (intermittent water) PL

pocosin PO

pothole (also Micro) PH

pothole lake (w) WN

raised bog RB

ribbed fen RG

sabkha SAB

salt marsh SM

seep (also Micro) SEE

semi-open depression SOD

slough (intermittent water) SL

string bog SY

swamp SW

tidal flat TF

tidal marsh TM

Microfeatures:

dune slack (also LF) DS

ephemeral stream (also LF) ES

intermittent stream (also 

LF)

INT

playette PL

pothole (also LF) PH

vernal pool (seasonal 

water)

VP
USDA-NRCS 3–37 September 2012

 15. WATER BODIES (discrete “surface water” features; 

primarily permanent open water, which in soil survey 

reports is commonly treated as the generic map unit 

“water” [e.g., lake] or as a spot/line symbol [e.g., perennial 

stream]).

Landscapes:

bay [coast] (also LF) BY

estuary (also LF) ES

gulf (also LF) GU

lagoon (also LF) LG

ocean OC

sea (also LF) SEA

sound (also LF) SO

strait (also LF) ST

Landforms:

axial stream AX

bay [coast] (also LS) BAY

bayou WC

cove [water] COW

dune lake DUL

estuary (also LS) WD

fjord FJ

glacial lake WE

gulf (also LS) GU

gut [channel] (also Micro) WH

ice-marginal stream IMS

inlet IL

lagoon (also LS) WI

lagoon channel LCH

lake WJ

marine lake ML

nearshore zone NZ

oxbow lake WK

perennial stream (also 

Micro)

PS

playa lake WL

pluvial lake PLL

pothole lake WN

proglacial lake WO

river RIV

sag pond (also Micro) SGP

salt pond (also Micro) WQ

sea (also LS) SEA

shoal WR

slackwater WS

slough SL

sound (also LS) SO

strait (also LS) STT

stream (permanent water) STR

tarn (also Micro) TAR

thermokarst lake WV

tidal inlet TI

tidal inlet [relict] TIR

tunnel-valley lake TVL

Microfeatures:

channel (permanent water) CH

gut [channel] (also LF) WH

perennial stream (also LF) PS

pond PON

pool POO

sag pond (also LF) SP

salt pond (also LF) WQ

tank TA

tarn (also LF) TN
USDA-NRCS 3–38 September 2012

 16. SUBAQUEOUS FEATURES (discrete underwater features 

[that commonly can support rooted plants] and adjacent 

features ordinarily found below permanent open water; 

historically, in soil survey reports these underwater 

features have been included in the generic map unit 

“water.” Subaqueous “Landscape” terms are obviously not 

terrestrial but are earth-surface features).

Landscapes:

bay [coast] (w; also LF) BY

estuary (w; also LF) ES

gulf (w; also LF) GU

lagoon (w; also LF) LA

ocean (w) OC

sea (w; also LF) SEA

sound (w; also LF) SO

strait (w; also LF) ST

Landforms:

barrier cove BAC

bay [coast] (w; also LS) BAY

bay bottom BOT

cove [water] (w) CO

estuary (also LS) WD

flood-tidal delta FTD

flood-tidal delta flat FTF

flood-tidal delta slope FTS

fluviomarine bottom FMB

gulf (w; also LS) GU

inlet IL

lagoon (also LS) WI

lagoon bottom LBO

lagoon channel LCH

lake WJ

lakebed (w) LB

longshore bar LON

mainland cove MAC

marine lake ML

nearshore zone NZ

reef RF

sea (w; also LS) SEA

shoal WR

sound (w; also LS) SO

strait (w; also LS) STT

submerged back-barrier 

beach

SBB

submerged mainland beach SMB

submerged point bar 

[coast]

SPB

submerged wave-built 

terrace

SWT

submerged wave-cut 

platform

SWP

tidal inlet TI

tidal inlet [relict] TIR

washover-fan flat WFF

washover-fan slope WFS

Microfeatures:

channel (permanent water) CH gut [channel] (w) WH

Anthropogenic Features:

dredge-deposit shoal DDS dredged channel DC
USDA-NRCS 3–39 September 2012

PART III: SURFACE MORPHOMETRY

A) Elevation: The height of a point on the earth’s surface relative 

to mean sea level (msl); indicate units; e.g., 106 m or 348 ft.

B) Slope Aspect: The compass bearing (in degrees, corrected for 

declination) that a slope faces, viewed downslope; e.g., 287°.

C) Slope Gradient: The angle of the ground surface (in percent) 

through the site and in the direction that overland water would 

flow (commonly referred to as slope); e.g., 18%.

D) Slope Complexity: Describe the relative uniformity (smooth 

linear or curvilinear=simple or S) or irregularity (complex or C) 

of the ground surface leading downslope through the point of 

interest; e.g., simple or S.

(adapted from Wysocki et al., 2000)

Simple vs. Complex

E) Relative Slope Segment Position (called geomorph_

slope_segment in NASIS): If useful to subdivide long slopes, 

describe the relative slope location of the area of interest.

Relative Slope 

Segment Position Code Criteria

lower third LT on lower third

middle third MT on middle third

upper third UT on upper third
USDA-NRCS 3–40 September 2012

F) Slope Shape: Slope shape is described in two directions: 

1) up and down slope (perpendicular or “normal” to the 

contour; called slope_down in NASIS); and 2) across slope 

(along the horizontal contour; called slope_across in NASIS). 

These two descriptors are commonly reported as a pair. The 

first term refers to up and down slope (or vertical), and the 

second term refers to across slope; e.g., Linear, Convex, or LV.

Down Slope

(Vertical)

Across Slope

(Horizontal) Code

concave concave CC

concave convex CV

concave linear CL

convex concave VC

convex convex VV

convex linear VL

linear concave LC

linear convex LV

linear linear LL

CV

L = Linear; V = Convex; C = Concave 

CC

VV VC

LV LC

CL

VL

LL

(adapted from Wysocki et al., 2000) 

Surface flow pathway
USDA-NRCS 3–41 September 2012

G) Hillslope—Profile Position (commonly called Hillslope 

Position): Two-dimensional descriptors of parts of line 

segments (i.e., slope position) along a transect that runs up 

and down the slope; e.g., backslope or BS. This set of terms is 

best applied to transects or points, not areas.

Position Code

summit SU

shoulder SH

backslope BS

footslope FS

toeslope TS

backslope

footslope

toeslope

shoulder summit

SU SH

BS FS SH

BS

SH

FS SH

BS

SH

FS

TS TS

FS

BS

SH SU

FS

BS

SH

SU

General

Scale

Detailed

Scale 

Simple Slopes Complex Slopes

(adapted from Wysocki et al., 2000)

H) Geomorphic Component (Geomorphic Position in PDP): 

Three-dimensional descriptors of parts of landforms or 

microfeatures that are best applied to areas. Other unique 

descriptors are available for Hills, Terraces and Stepped 

Landforms, Mountains, and Flat Plains; e.g. (for Hills), nose 

slope or NS.
USDA-NRCS 3–42 September 2012

1) Hills Code

interfluve IF

crest CT

head slope HS

nose slope NS

side slope SS

free face FF

base slope BS

Lower order stream

base slope

side

slope

no

sl

se

ope

head

slope interfluve

base slope

Alluvial

fill

(Wysocki et al., 2012)

Colluviumand s ol pe al ul vui m

crest

free face (i.e., rock outcrop)

Higher order stream

2) Terraces and Stepped Landforms Code

riser RI

tread TR

TREAD

RISER

100 yr. Flood Zone

Annual

Flood

Plain

Uplands Terraces Flood-Plain Steps

(adapted from Wysocki et al., 2000)
USDA-NRCS 3–43 September 2012

3) Mountains Code

mountaintop MT

mountainflank MF

upper third – mountainflank UT

center third – mountainflank CT

lower third – mountainflank LT

free face FF

mountainbase MB

4) Flat Plains Code

dip DP

rise RI

talf TF
USDA-NRCS 3–44 September 2012

I) Microrelief: Small, relative differences in elevation between 

adjacent areas on the earth’s surface; e.g., microhigh or MH.

Microrelief Code

microhigh MH

microlow ML

microslope MS

 NOTE: See graphic p. 2–54.

J) Drainage Pattern: The arrangement of drainage channels on 

the land surface; also called drainage network.

Drainage Pattern Code

annular AN

artificial AR

centripetal CE

dendritic DN

deranged DR

karst KA

parallel PA

pinnate PI

radial RA

rectangular RE

thermokarst TH

trellis TR
USDA-NRCS 3–45 September 2012

Radial Rectangular

Parallel Pinnate

Deranged

(nonintegrated)

local

depression

Centripetal Dendritic

basin,

lakebed

Annular Artificial

Karst
USDA-NRCS 3–46 September 2012

Thermokarst Trellis

REFERENCES

Fenneman, N.M. 1931. Physiography of the western United States. 

McGraw-Hill Co., New York, NY.

Fenneman, N.M. 1938. Physiography of the eastern United States. 

McGraw-Hill Co., New York, NY.

Fenneman, N.M. 1946 (reprinted 1957). Physical divisions of the 

United States. U.S. Geological Survey. U.S. Gov. Print. Office, 

Washington, DC. 1 sheet; 1:7,000,000.

Ruhe, R.V. 1975. Geomorphology: Geomorphic processes and 

surficial geology. Houghton-Mifflin, Boston, MA.

Schoeneberger, P.J., and D.A. Wysocki. 1996. Geomorphic 

descriptors for landforms and geomorphic components: Effective 

models and weaknesses. In Agronomy abstracts, ASA, Madison, WI.

Soil Survey Staff. 2012. Glossary of landform and geologic terms. 

Part 629, National soil survey handbook (NSSH) [Online]. USDA, 

NRCS, National Soil Survey Center, Lincoln, NE.

Wahrhaftig, C. 1965. Physiographic divisions of Alaska. U.S. Geol. 

Surv. Prof. Pap. 482.

Wysocki, D.A., P.J. Schoeneberger, D. Hirmas, and H.E. LaGarry. 

2012. Geomorphology of soil landscapes. In P.M. Huang et al. 

(ed.) Handbook of soil science: Properties and processes, 2nd ed. 

CRC Press, Taylor and Francis Group, LLC, Boca Raton, FL. ISBN: 

978–1–4398–0305–9.

Wysocki, D.A., P.J. Schoeneberger, and H.E. LaGarry. 2000. 

Geomorphology of soil landscapes. In M.E. Sumner (ed.) Handbook 

of soil science. CRC Press, LLC, Boca Raton, FL. ISBN: 0–8493–

3136–6.
USDA-NRCS 4–1 September 2012

SOIL TAXONOMY

P.J. Schoeneberger, D.A. Wysocki, and J.V. Chiaretti, NRCS, Lincoln, NE

INTRODUCTION

The purpose of this section is to expand upon and augment 

the abbreviated soil taxonomic contents of the “Profile/Pedon 

Description” section. Complete definitions are found in Keys to Soil 

Taxonomy (Soil Survey Staff, 2010a).

HORIZON AND LAYER DESIGNATIONS

NOTE: Horizons are considered to be layers of pedogenically 

derived or modified material. Layers are deemed to be zones of 

nonpedogenically derived/modified material (e.g., geologic strata).

MASTER AND TRANSITIONAL HORIZONS or LAYERS—

Horizon Criteria 1

O

Organic soil materials other than limnic materials. The 

mineral fraction is a small percent by volume and is 

<80% by weight.

A

Mineral soil, formed at the surface or below an O 

horizon, little remnant rock structure, and one or 

more: 1) accumulation of humified organic matter but 

dominated by mineral matter, and not dominated by 

E or B horizon properties; 2) properties resulting from 

cultivation, pasturing, or similar disturbance; or 3) 

morphology resulting from surficial processes different 

from the underlying B or C. Excludes recent eolian or 

alluvial deposits that retain stratification.

AB

or AE

or AC

Dominantly A horizon characteristics but also contains 

some B, E, or C horizon attributes.

A/B

or A/E

or A/C

Discrete, intermingled bodies of two horizons: A 

material dominates with lesser but discrete bodies of 

B, E, or C material.

E

Mineral soil with some loss of silicate clay, iron, 

aluminum, and/or organic matter leaving a net 

concentration of sand and silt; little or no remnant 

rock structure; typically lighter color (higher value, 

chroma) and coarser texture than A.
USDA-NRCS 4–2 September 2012

Horizon Criteria 1

EA

or EB

or EC

Dominantly E horizon characteristics but also contains 

some A, B, or C horizon attributes.

E/A

or E/B

Discrete, intermingled bodies of two horizons: E 

material dominates with lesser but discrete bodies of 

A or B material.

E and Bt

B and E

Thin, heavier textured lamellae (Bt) within a 

predominantly E horizon with less clay (or thin E 

layers within a predominantly B horizon).

BA

or BE

or BC

Dominantly B characteristics but also contains some 

A, E, or C horizon attributes.

B/A

or B/E

or B/C

Discrete, intermingled bodies of two horizons: B 

material dominates with lesser but discrete bodies of 

A, E, or C material.

B

Mineral soil, typically formed below O, A, or E; little 

or no rock structure; and with one or more of the 

following:

1) illuvial accumulation of silicate clay, Fe, Al, 

humus, carbonate, gypsum, silica, or salt 

more soluble than gypsum (one or more);

2) removal, addition, or transformation of 

carbonates, gypsum, or more soluble salts;

3) residual concentration of oxides, sesquioxides, 

and silicate clays (one or more);

4) sesquioxide coatings;

5) alterations that form silicate clays or liberate 

oxides and form pedogenic structure;

6) Brittleness;

7) Strong gleying in the presence of aquic 

conditions (or artificial drainage); layers 

with gleying but no other pedogenic change 

are not B horizons. Most B horizons are or 

were subsurface horizons. Some formed at 

the surface by accumulation of evaporites. 

Cemented and brittle layers that have other 

evidence of pedogenesis are included as B 

horizons.
USDA-NRCS 4–3 September 2012

Horizon Criteria 1

CB

or CA

Dominantly C horizon characteristics but also contains 

some B or A horizon attributes.

C/B

or C/A

Discrete, intermingled bodies of two horizons: C 

material dominates, with lesser but discrete bodies of 

A or B material.

C

Mineral soil, soft bedrock (excluding Strongly 

Cemented to Indurated bedrock unless highly 

cracked); layer little affected by pedogenesis and 

lacks properties of O, A, E, or B horizons. May or may 

not be parent material of the solum.

L

Limnic soil materials. Sediments deposited in a body 

of water (subaqueous) and dominated by organic 

materials (aquatic plant and animal fragments and 

fecal material) and lesser amounts of clay.

W

A layer of liquid water (W) or permanently frozen ice 

(Wf), within or beneath the soil (excludes water / ice 

above soil).

M Root-limiting subsoil layers of human-manufactured 

materials; e.g., geotextile liner.

R Hard bedrock (continuous, coherent Strongly 

Cemented to Indurated Cementation Classes).

1 Soil Survey Staff, 2010a.

HORIZON SUFFIXES—Historically referred to as “Horizon 

Subscripts,” “Subordinate Distinctions,” 1 “Horizon_Designation_

Suffix” in NASIS, and “Suffix Symbols” in Keys to Soil Taxonomy. 2

(Historical nomenclature and conversions are shown in the tables on 

page 4-6.)

Horizon 

Suffixes Criteria 2

a Highly decomposed organic matter (OM); rubbed fiber 

content <17% (by vol.); used only with O (see e, i).

aa 3 (proposed) Accumulation of anhydrite (CaSO4).

b

Buried genetic horizon (not used with organic 

materials or to separate organic from mineral 

materials).

c

Concretions or nodules; significant accumulation of 

cemented bodies enriched with Fe, Al, Mn, Ti (cement 

not specified except excludes a predominance of silica 

[see q]); not used for carbonates or soluble salts (see

z).
USDA-NRCS 4–4 September 2012

Horizon 

Suffixes Criteria 2

co

Coprogenous earth (used only with L); organic 

materials deposited under water and dominated by 

fecal material from aquatic animals.

d

Physical root restriction due to high bulk density 

(natural or human-induced conditions; e.g., lodgment 

till, plow pans.

di

Diatomaceous earth (used only with L); materials 

deposited under water and dominated by the siliceous 

diatom remains.

e

Moderately (intermediately) decomposed organic 

matter; rubbed fiber content 17 to <40% (by vol.); 

used only with O (see a, i).

f Permafrost (permanently frozen subsurface soil or 

ice); excludes seasonally frozen ice and surface ice.

ff

Dry permafrost (permanently frozen soil; not used for 

seasonally frozen soil; no continuous ice bodies [see

f]).

g

Strong gley (Fe reduced and pedogenically removed); 

typically ≤2 chroma; may have other redoximorphic 

features (RMF); not used for geogenic gray colors.

h

Illuvial organic matter (OM) accumulation (with B: 

accumulation of illuvial, amorphous OM-sesquioxide 

complexes); coats sand and silt particles and may 

fill pores; use Bhs if significant accumulation of 

sesquioxides and moist chroma and value ≤3.

i Slightly decomposed organic matter; rubbed fiber 

content ≥40% (by vol.); used only with O (see a, e).

j Jarosite accumulation; e.g., acid sulfate soils.

jj

Evidence of cryoturbation; e.g., irregular or broken 

horizon boundaries, sorted rock fragments (patterned 

ground), or OM in lower boundary between active 

layer and permafrost layer.

k Pedogenic carbonate accumulation (e.g., CaCO3; 

<50% by vol.).

kk Major pedogenic carbonate accumulation; soil fabric is 

plugged ≈ continuous (≥50% by vol. estimated).

m

Continuous pedogenic cementation or induration 

(>90% cemented, even if fractured); physically root 

restrictive. Dominant cement type can be indicated by 

additional letters; e.g., km or kkm—carbonates, qm—

silica, kqm—carbonates and silica, sm—iron, yym—

gypsum, zm—salts more soluble than gypsum.
USDA-NRCS 4–5 September 2012

Horizon 

Suffixes Criteria 2

ma

Marl (used only with L); materials deposited under 

water and dominated by a mixture of clay and CaCO3; 

typically gray or beige.

n Pedogenic exchangeable sodium accumulation.

o Residual accumulation of sesquioxides.

p

Tillage or other disturbance of surface layer (pasture, 

plow, etc.). Designate Op for disturbed organic 

surface, Ap for mineral surface even if the layer 

clearly was originally an E, B, C, etc.

q Accumulation of secondary (pedogenic) silica.

r

Used with C to indicate weathered or soft bedrock 

(root-restrictive saprolite or soft bedrock), such 

as weathered or partially consolidated sandstone, 

siltstone, or shale; materials are sufficiently 

incoherent to allow hand digging with a spade 

(Excavation Difficulty classes are Low to High). Roots 

only penetrate along joint planes.

s

Significant illuvial accumulation of amorphous, 

dispersible sesquioxides and organic matter 

complexes and moist color value or chroma ≥4. Used 

with B horizon; used with h as Bhs if moist color value 

and chroma are ≤3.

se

Presence of sulfides (in mineral or organic horizons). 

Typically dark colors (e.g., value ≤4, chroma ≤2); 

may have a sulfurous odor.

ss

Slickensides; e.g., oblique shear faces 20-60o off 

horizontal; caused by shrink-swell clay action; wedgeshaped peds and seasonal surface cracks also are 

commonly present.

t

Accumulation (by translocation or illuviation) of 

silicate clays (clay films, lamellae, or clay bridging in 

some part of the horizon).

u

Presence of human-manufactured materials 

(artifacts); e.g., asphalt, bricks, plastic, glass, metals, 

construction debris, garbage.

v

Plinthite (high Fe, low OM, reddish contents; firm or 

very firm moist consistence; irreversible hardening 

with repeated wetting and drying).

w

Incipient color or pedogenic structure development, 

minimal illuvial accumulations; used only with B 

horizons, excluded from use with transition horizons.
USDA-NRCS 4–6 September 2012

Horizon 

Suffixes Criteria 2

x

Fragipan or fragic characteristics (pedogenetically 

developed brittleness, firmness, bleached prisms, high 

bulk density, root restrictive).

y Accumulation of gypsum (CaSO4 • 2H2O); <50% by 

volume (estimated).

yy

Dominance of gypsum (≈ ≥50% by vol. estimated); 

light colored (e.g., value ≥7, chroma ≤4); may be 

pedogenically derived or inherited transformation of 

primary gypsum from parent material.

z Pedogenic accumulation of salts more soluble than 

gypsum; e.g., NaCl.

1 Soil Survey Division Staff, 1993.

2 Soil Survey Staff, 2010a.

3 Personal communication with Soil Survey Standards Staff, 2012.

HORIZON AND LAYER DESIGNATIONS CONVERSION 

CHARTS—(NOTE: Gray boxes indicate the year the convention was 

first adopted.)

Master Horizons, Layers, or Combinations

1951 1 1962 2, 

1975 3 1982 4 1998 5 2006 6,

2010 7

Aoo or 

Ao O O O O

Aoo O1 Oi and/or Oe Oi and/or Oe Oi and/or Oe

Ao O2 Oe and/or Oa Oe and/or Oa Oe and/or Oa

— — Oi Oi Oi

— — Oe Oe Oe

— — Oa Oa Oa

A A A A A

A1 A1 A A A

A2 A2 E E E

A3 A3 AB or EB AB or EB AB or EB

AB AB — — —

A&B A&B A/B or E/B A/B or E/B A/B or E/B

AC AC AC AC AC

— — E and Bt E and Bt E and Bt
USDA-NRCS 4–7 September 2012

Master Horizons, Layers, or Combinations

1951 1 1962 2, 

1975 3 1982 4 1998 5 2006 6,

2010 7

B B B B B

B1 B1 BA or BE BA or BE BA or BE

B&A B&A B/A or B/E B/A or B/E B/A or B/E

B2 B2 B or Bw B or Bw B or Bw

G g 8 Ag, Bg, Cg Ag, Bg, Cg Ag, Bg, Cg

B3 B3 BC or CB BC or CB BC or CB

— — B/C, C/B, C/A B/C, C/B, C/A B/C, C/B, C/A

C C C C C

Cca Cca Bk Bk Bk, Bkk 6

Ccs Ccs By, Cy By, Cy By or Byy,

Cy or Cyy 7

D — — — —

Dr R R R R

— — — L 3, 6 L

— — — — M 6

— — — W W

1 Soil Survey Staff, 1951.

2 Soil Survey Staff, 1962; same content used in Soil Taxonomy

(Soil Survey Staff, 1975), except for addition of Limnic (L) 

horizon. 3

3 Soil Survey Staff, 1975. Limnic materials and limnic layer were 

recognized in 1975, formally dropped in 1985 (National Soil 

Taxonomy Handbook 615.30); master L horizon was formally 

adopted in 2006. 6

4 Guthrie and Witty, 1982.

5 Soil Survey Staff, 1998.

6 Soil Survey Staff, 2006.

7 Soil Survey Staff, 2010a.

8 Master horizon G (1951) was changed to a horizon suffix (g) that 

can be used with master horizon A, B, or C; e.g., Bg.
USDA-NRCS 4–8 September 2012

HORIZON SUFFIXES—(NOTE: Gray boxes indicate the year the 

convention was first adopted.)

Horizon Suffixes

(also called “Horizon Subscripts” and “Subordinate 

Distinctions”)

1951 1 1962 2, 

1975 2 1982 3 1998 4 2010 5

— — a a a

b b b b b

ca ca k k k

cn cn c c c

— — — co 6 co

cs cs y y y

— — — d (1988) 7 d

— — — di 6 di

— — e e e

f f f f f

— — — ff ff

g g g g g

h h h h h

ir ir s s s

— — i i i

— — — j j

— — — jj jj

ca ca k k k

— — — — kk 8 (2006)

m m 9 m m m

— — — ma 6 ma

— — n n n

— — o o o

p p p p p

si si q q q

r 10 — r r r

ir ir s s s

sa sa n n n

— — — — se 9 (2011)

— si q q q
USDA-NRCS 4–9 September 2012

Horizon Suffixes

(also called “Horizon Subscripts” and “Subordinate 

Distinctions”)

1951 1 1962 2, 

1975 2 1982 3 1998 4 2010 5

— — — ss (1991) ss

t t t t t

u — — — u 8 (2006)

— — v v v

— — w w w

— x x x x

cs cs y y y

— — — — yy 5

sa sa z z z

1 Soil Survey Staff, 1951.

2 Soil Survey Staff, 1962; same content also used in Soil Taxonomy

(Soil Survey Staff, 1975).

3 Guthrie and Witty, 1982.

4 Soil Survey Staff, 1998.

5 Soil Survey Staff, 2010a.

6 Soil Survey Staff, 1999.

7 Soil Survey Staff, 1988.

8 Soil Survey Staff, 2006.

9 The definition is changed to no longer include fragipans (which 

become “x”).

10 Definition of r (1951; dropped 1962 2) is not the same as used 

since 1981. 3
USDA-NRCS 4–10 September 2012

1 Very fine sand fraction (0.05 - 0.1 mm) is treated as silt for Soil Taxonomy family

groupings; coarse fragments are considered the equivalent of coarse sand in the 

boundary between silty and loamy classes.

100

100

100

90

90

90

80

80

80

70

70

70

60

60

60

50

40

40

40

30

30

30

20

20

20

10

10

10

Clay

Separate, %

Sand Separate, %

Silt Separate, %

50

50

(Soil) Textural Triangle:

Family Particle-Size Classes ( )

sandy

clayey

(very-fine)

clayey

(fine)

finesilty fine-loamy 1 1

coarse-loamy1 coarsesilty1
USDA-NRCS 4–11 September 2012

1

Very fine sand fraction (0.05 - 0.1 mm) is treated as silt for Soil Taxonomy family

groupings; coarse fragments are considered the equivalent of coarse sand in the 

boundary between silty and loamy classes.

100

100

100

90

90

90

80

80

80

70

70

70

60

60

60

50

40

40

40

30

30

30

20

20

20

10

10

10

Clay

Separate, %

Sand Separate, %

Silt Separate, %

50

50

Combined Textural Triangles:

Fine Earth Texture Classes ( )

Family Particle-Size Classes ( )

sand loamy

 sand

sandy loam

clay

sandy

clay

sandy clay loam

clay loam

loam

silty

clay

silty

clay loam

silt loam

silt

sandy

clayey

(very-fine)

clayey

(fine)

fine

silty

- fine loamy 1 1

-

coarse loamy1

- coarse

silty

-

1

SOIL MOISTURE REGIMES—Refers to soil moisture or ground 

water presence in or on soil at tensions >0 and ≤1500 kPa 

(≈ ≤15 bar).

Soil moisture conditions of a pedon (i.e., Soil Water State) can be 

estimated or measured at the time of observation and subsequently 

assigned to a Water State class (or subclass; see p. 1–15). In a 

broader context, the prevailing soil moisture condition of a site can 

be estimated or measured for “normal years” (i.e., most typical or 

dominant climatic conditions). Class assignment takes into account: 

1) the extent of ground water influence (usually via “depth to”) 

and 2) the seasonal status of water held at tensions <1500 kPa 

(≈ <15 bar) in the moisture control section. 1 In soil taxonomy 1, 

soil moisture regimes are assigned as classes (e.g., Ustic Soil 

Moisture Regime) and are used at the higher categories of the 

system (i.e., from Order down through Subgroup).
USDA-NRCS 4–12 September 2012

Soil 

Moisture 

Regime

Criteria 1

(generalized, abbreviated)

aquic A reducing regime for soils that are free of dissolved 

oxygen and saturated (seasonal ground water 

fluctuations typical). Unlike other regimes, the aquic 

regime may occur temporarily for only a few days.

peraquic A reducing regime for soils that are free of dissolved 

oxygen and permanently saturated (ground water 

is almost always above, at, or very close to the 

surface).

aridic

(torric) 2

The predominantly dry regime for soils of arid and 

semiarid climates that are unsuitable for cultivation 

without irrigation. Soil is dry (in all parts of soil 

moisture control section) >50% of all days annually 

when soil is >5 °C at 50 cm and moist in some part 

for <90 consecutive days when soil is >8 °C at 50 cm 

in normal years.

udic The predominantly moist regime for soils of humid 

climates with well distributed rainfall. Soil is dry (in 

any part of soil moisture control section) for <90 

cumulative days in normal years.

perudic An extremely wet regime for soils of climates where 

precipitation exceeds evapotranspiration in all months 

in normal years. Soil is almost always moist; soil 

tension is rarely >100 kPa (≈ >1 bar).

ustic The temporarily dry regime for soils of climates that 

are intermediate between dry (aridic) and moist 

(udic). Soil is intermittently moist and dry; moisture 

limited but usually available when climate is suitable 

for plant growth. Soil is moist >180 cumulative days 

or >90 consecutive days.

xeric The seasonally dry regime for soils of Mediterranean 

climates with cool, moist winters and warm, 

dry summers. Soil is moist in all parts for ≥45 

consecutive days in the 4 months following the winter 

solstice and dry in all parts for ≥45 consecutive days 

in the 4 months following the summer solstice. Soil is 

also moist in some part >50% of all days when soil 

is >5 °C at depth of 50 cm or moist in some part for 

≥90 consecutive days when soil is >8 °C at depth of 

50 cm in normal years.

1 Complete criteria available in Keys to Soil Taxonomy, 11th ed. 

(Soil Survey Staff, 2010a).

2 Aridic and torric are terms for the same soil moisture regime, but 

they are used in different categories in soil taxonomy. Limits set 
USDA-NRCS 4–13 September 2012

for soil temperature exclude from this regime soils in very cold 

and dry polar regions and in areas at high elevations. Such soils 

are considered to have anhydrous conditions.

SOIL TEMPERATURE REGIMES AND CLASSES (per Keys to Soil 

Taxonomy 1, 2)—

Soil 

Temperature 

Regimes 1

Soil 

Temperature 

Classes 2

Criteria: MAST 3 measured at 

50 cm or at the upper boundary 

of a root-limiting layer if 

shallower

Gelic (see below) ≤0 °C in Gelic suborders and Gelic 

great groups or <1 °C in Gelisols 

(permafrost expected)

Hypergelic ≤ -10 °C

Pergelic -10 to -4 °C

Subgelic -4 to 1 °C

Cryic (no family 

temperature 

class)

≥0 to <8 °C, but no permafrost, and

1. In mineral soils: the MSST 4 is:

a. If soil is not saturated during

 summer and

(1) If no O horizon: ≥0 to

 15 °C; or

(2) If there is an O horizon: ≥0

 to 8 °C; or 

b. If soil is saturated during

 summer and

(1) If no O horizon: ≥0 to

 13 °C; or

(2) If there is an O horizon or a 

histic epipedon: ≥0 to

 6 °C.

2. In organic soils: ≥0 to 6 °C.

For soils with a difference between mean summer and mean winter soil 

temperature of ≥6 °C:

Frigid Frigid ≥0 to <8 °C (but warmer than cryic 

in summer)

Mesic Mesic 8 to <15 °C

Thermic Thermic 15 to <22 °C

Hyperthermic Hyperthermic ≥22 °C

For soils with a difference between mean summer and mean winter soil 

temperature of <6 °C:

Isofrigid Isofrigid <8 °C

Isomesic Isomesic 8 to <15 °C

Isothermic Isothermic 15 to <22 °C

Isohyperthermic Isohyperthermic ≥22 °C
USDA-NRCS 4–14 September 2012

1 Soil temperature regimes are used as criteria in the suborder, 

great group, and subgroup categories of soil taxonomy (Soil 

Survey Staff, 2010a).

2 Soil temperature classes are used as differentiae in the family 

category of soil taxonomy, excluding cryic soils (Soil Survey Staff, 

2010a).

3 MAST=Mean annual soil temperature (Soil Survey Staff, 1999).

4 MSST=Mean summer soil temperature (see Soil Survey Staff, 

1999, p. 108).

REFERENCES

Guthrie, R.L., and J.E. Witty. 1982. New designations for soil 

horizons and layers and the new Soil Survey Manual. Soil Sci. Soc. 

Am. J. 46:443–444.

Natural Resources Conservation Service, Soil Classification Staff. 

1999. Personal communication. USDA, NRCS, National Soil Survey 

Center, Lincoln, NE.

Soil Survey Division Staff. 1993. Soil survey manual. USDA, SCS, 

Agric. Handb. 18. U.S. Gov. Print. Office, Washington, DC.

Soil Survey Staff. 1951. Soil survey manual. USDA, SCS, Agric. 

Handb. 18. U.S. Gov. Print. Office, Washington, DC.

Soil Survey Staff. 1962. Identification and nomenclature of soil 

horizons. Supplement to Agric. Handb.18, Soil Survey Manual 

(replacing pages 173–188). USDA, SCS. U.S. Gov. Print. Office, 

Washington, DC.

Soil Survey Staff. 1975. Soil taxonomy. USDA, SCS, Agric. Handb. 

436. U.S. Gov. Print. Office, Washington, DC.

Soil Survey Staff. 1988. Keys to soil taxonomy, 4th ed. SMSS Tech. 

Monogr. 6, Cornell Univ., Ithaca, NY.

Soil Survey Staff. 1998. Keys to soil taxonomy, 8th ed. USDA, SCS. 

U.S. Gov. Print. Office, Washington, DC.

Soil Survey Staff. 1999. Soil taxonomy, 2nd ed. USDA, NRCS, Agric. 

Handb. 436. U.S. Gov. Print. Office, Washington, DC.

Soil Survey Staff. 2006. Keys to soil taxonomy, 10th ed. USDA, 

NRCS. U.S. Gov. Print. Office, Washington, DC.

Soil Survey Staff. 2010a. Keys to soil taxonomy, 11th ed. USDA, 

NRCS. U.S. Gov. Print. Office, Washington, DC.

Soil Survey Staff. 2010b. National soil survey handbook (NSSH) 

[Online]. USDA, NRCS, National Soil Survey Center, Lincoln, NE 

(http://soils.usda.gov/technical/handbook/).
USDA-NRCS 5–1 September 2012

GEOLOGY

P.J. Schoeneberger, D.A. Wysocki, and E.C. Benham, NRCS, Lincoln, NE

INTRODUCTION

The purpose of this section is to expand and augment the geologic 

information found or needed in the “Site Description” and “Profile/

Pedon Description” sections.

BEDROCK - KIND—

This table is repeated here from the “Site Selection” section for 

convenience in using the following rock charts.

Kind 1 Code Kind 1 Code

IGNEOUS—INTRUSIVE

anorthosite ANO pyroxenite PYX

diabase DIA quartzite QZT

diorite DIO quartz-diorite QZD

gabbro GAB quartz-monzonite QZM

granite GRA syenite SYE

granitoid 2 GRT syenodiorite SYD

granodiorite GRD tonalite TON

monzonite MON ultramafic rock 2 UMU

peridotite PER

IGNEOUS—EXTRUSIVE

a’a lava AAL pahoehoe lava PAH

andesite AND pillow lava PIL

basalt BAS pumice (flow, 

coherent) PUM

block lava BLL rhyolite RHY

dacite DAC scoria (coherent mass) SCO

latite LAT tachylite TAC

obsidian OBS trachyte TRA
USDA-NRCS 5–2 September 2012

Kind 1 Code Kind 1 Code

IGNEOUS—PYROCLASTIC

ignimbrite IGN tuff, welded TFW

pyroclastics 

(consolidated) PYR tuff breccia TBR

pyroclastic flow PYF volcanic breccia VBR

pyroclastic surge PYS volcanic breccia, acidic AVB

tuff TUF volcanic breccia, basic BVB

tuff, acidic ATU volcanic sandstone VST

tuff, basic BTU

METAMORPHIC

amphibolite AMP metavolcanics MVO

gneiss GNE mica schist MSH

gneiss, biotite BTG migmatite MIG

gneiss, granodiorite GDG mylonite MYL

gneiss, hornblende HBG phyllite PHY

gneiss, migmatitic MMG schist SCH

gneiss, muscovite-biotite MGB schist, biotite BTS

granofels GRF schist, graphitic GRS

granulite GRL schist, muscovite MVS

greenstone GRE schist, sericite SCS

hornfels HOR serpentinite SER

marble MAR siltite SIT

meta-conglomerate MCN slate SLA

metaquartzite MQT slate, sulfidic SFS

metasedimentary rocks 2 MSR soapstone (talc) SPS

metasiltstone MSI

SEDIMENTARY—CLASTICS

arenite ARE mudstone MUD

argillite ARG ortho-quartzite OQT

arkose ARK porcellanite POR

breccia, nonvolcanic 

(angular fragments) NBR sandstone SST
USDA-NRCS 5–3 September 2012

Kind 1 Code Kind 1 Code

breccia, nonvolcanic, 

acidic ANB sandstone, calcareous CSS

breccia, nonvolcanic, 

basic BNB shale SHA

claystone CST shale, acid ASH

conglomerate (rounded 

fragments) CON shale, calcareous CSH

conglomerate, 

calcareous CCN shale, clayey YSH

fanglomerate FCN siltstone SIS

glauconitic sandstone GLS siltstone, calcareous CSI

graywacke GRY

EVAPORITES, ORGANICS, AND PRECIPITATES

bauxite BAU limestone, argillaceous RLS

chalk CHA limestone, cherty CLS

chert CHE limestone, coral COR

coal COA limestone, phosphatic PLS

diatomite DIA limonite LIM

dolomite (dolostone) DOL novaculite NOV

gypsum GYP travertine TRV

limestone LST tripoli TRP

limestone, arenaceous ALS tufa TUA

INTERBEDDED (alternating layers of different sedimentary 

lithologies)

limestone-sandstoneshale LSS sandstone-shale SSH

limestone-sandstone LSA sandstone-siltstone SSI

limestone-shale LSH shale-siltstone SHS

limestone-siltstone LSI

1 Definitions for kinds of bedrock are found in the “Glossary of 

Landform and Geologic Terms,” NSSH, Part 629 (Soil Survey 

Staff, 2012), or in the Glossary of Geology (Neuendorf et al., 

2005).

2 Generic term; use only with regional or reconnaissance surveys 

(Order 3, 4, 5; see Guide to Map Scales and Minimum-Size 

Delineations, p. 7–21).
USDA-NRCS 5–4 September 2012

ROCK CHARTS

The following rock charts (Igneous, Metamorphic, and 

Sedimentary and Volcaniclastic) summarize grain size, 

composition, or genetic differences between related rock types. 

NOTE: 1) Most, but not all, of the rocks in these tables are found 

in the NASIS choice lists. Those not in NASIS are uncommon in the 

pedosphere but are included in the charts for completeness and 

to aid in the use of geologic literature. 2) Most, but not all, of the 

rocks presented in these tables can be definitively identified in the 

field; some may require additional laboratory analyses (e.g., grain 

counts, thin section analyses).
USDA-NRCS 5–5 September 2012 IGNEOUS ROCKS CHART KEY MINERAL COMPOSITION CRYSTALLINE TEXTURE Acidic (»felsic) Potassium (K) Feldspar > 2/3 of total Feldspar content Intermediate (---) Potassium (K) Feldspar and Plagioclase (Na, Ca) Feldspar in about equal proportions Basic (»mafic) Plagioclase (Na, Ca) Feldspar > 2/3 of total Feldspar content Ultrabasic

(»ultramafic)

Pyroxene and olivine

PEGMATITIC

(very coarse, 

uneven-sized

crystal grains)

Quartz

granite

pegmatite

No Quartz

syenite

pegmatite

Quartz No Quartz

monzonitepegmatite

Sodic (Na) Plagioclase

Quartz No Quartz

 diorite-

 pegmatite

Calcic (Ca)

Plagioclase

gabbro 

pegmatite

peridotite

(mostly olivine)

PHANERITIC

(crystals visible and 

of nearly equal size)

granite syenite quartz monzonite monzonite quartz-diorite granodiorite diorite gabbro pyoxenite (mostly pyroxene)

PORPHYRITIC

(relatively few 

visible crystals 

within a finegrained matrix)

granite

porphyry

syenite

porphyry

quartz 

monzonite 

porphyry

monzonite 

porphyry

quartz-diorite 

porphyry

diorite 

porphyry diabase

rhyolite

porphyry

trachyte

porphyry

quartzlatite 

porphyry

latite 

porphyry

dacite 

porphyry

andesite 

porphyry

porphyry 

basalt

APHANITIC

(crystals visible only 

with magnification)

micro 1 crypto 2

rhyolite trachyte quartz latite latite dacite andesite basalt } lava 3

GLASSY

(amorphous: 

no crystalline 

structure)

obsidian (and its varieties: perlite, pitchstone, pumice, and scoria)pyroclastics are shown on the Sedimentary and Volcaniclastic Rocks chart

1 Microcrystalline—crystals visible with ordinary magnification (hand lens, simple microscope)2 Cryptocrystalline—crystals only visible with SEM3 Lava – generic name for extrusive flows of nonclastic, aphanitic  rocks (rhyolite, andesite, and basalt)

(Schoeneberger and Wysocki, 1998)
USDA-NRCS 5–6 September 2012 METAMORPHIC ROCKS CHART NONFOLIATED STRUCTURE CRUDE ALIGNMENT FOLIATED STRUCTURE (e.g., banded) CONTACT METAMORPHISM MECHANICAL METAMORPHISM REGIONAL METAMORPHISM PLUTONIC METAMORPHISM Low Grade Medium Grade High Grade Very Low Grade Low Grade Medium Grade High Grade Exteme Grade granofels hornfels marble metaquartzite serpentinite soapstone (talc) crush breccia mylonite slate phyllite greenstone schist amphibolite gneiss granulite migmatite <-- metaconglomerate --> <----- metavolcanics -----> * Not all rock types listed here can be definitively identified in the field (e.g., may require grain counts). ** Not all rock types shown here are available on Bedrock - Kind choice list. They are included here for completeness and as aids to using geologic literature. (Schoeneberger and Wysocki, 1998)
USDA-NRCS 5–7 September 2012 SEDIMENTARY AND VOLCANICLASTIC ROCKS CLASTIC NONCLASTIC Dominant Grain Size Chemical Biochemical Organic Very Fine Fine Medium Coarse Evaporates, Precipitates Accretionates Reduzates <----- (Argillaceous) -----> (Arenaceous) (Rudaceous) < 0.002 mm 0.002 - 0.06 mm 0.06 - 2.0 mm >2.0 mm <-------- argillite --------> (more indurated, less laminated and fissile) <---------- shale ---------> (laminated, fissile) <------- mudstone -------> (nonlaminated, nonfissile)

(» equal clay and silt)

Sandstones (ss):

arenite

arkose

(mainly feldspar)

glauconitic ss

(“greensand”)

graywacke

(dark, “dirty” ss)

orthoquartzite

(mainly quartz)

breccia

(nonvolcanic, angular 

frags)

conglomerate

(nonvolcanic, 

rounded frags)

anhydrite

(CaSO4)

gypsum

(CaSO4 • 

2H O) 2

halite

(NaCl)

CARBONATE ROCKS

Limestones (ls)

(>50% calcite)

black shale

(organics and fine 

sediments)

bituminous ls

bog iron ores

coal

chemical typescalichetravertinetufa

accretionary typesbiostromal lsorganic reefpelagic ls(chalk)bio-clastic typescoquinaoolithic lslithographic ls

claystone

(nonlaminated, 

nonfissile)

siltstone

(nonlaminated, 

nonfissile)

VOLCANICLASTICS (includes Pyroclastics)

<------------------ ignimbrite ------------------>

<--------------------- tuff ---------------------->

agglomerate

(rounded frags)

volcanic breccia

(angular frags)

altered typesdolomite(>50% calcite + dolomite)phosphatic limestone

<------------ pumice (specific gravity <1.0; highly vesicular)-------------> OTHER NONCLASTIC ROCKS

<----- scoria (specific gravity >2.0; slightly or moderately vesicular) ------> Siliceous rocks (SiO2 dominated):

 chert (jasper, chalcedony, opal) diatomiterock phosphateiron-bearing rocks (Fe-SiO2 dominated)

(Schoeneberger and Wysocki, 2000)
USDA-NRCS 5–8 September 2012 MASS MOVEMENT (MASS WASTING) TYPES FOR SOIL SURVEY (landforms , processes, and sediments) LANDSLIDE Movement Types: FALL Free fall, bouncing, or rolling TOPPLE Forward rotation over a point SLIDE* Net lateral displacement along a slip face Rotational Slide Lateral displacement along a concave slip face with backward rotation Translational Slide Lateral displacement along a planar slip face; no rotation <------ Compound Slide ------> Intermediate between rotational and translational; e.g., a compound rock slide SPREAD A wet layer becomes “plastic”, squeezes up and out and drags along intact blocks or beds; e.g., extrusion, liquefaction (=Lateral Spread) FLOW The entire mass, wet or dry, moves as a viscous liquid COMPLEX LANDSLIDE Combination of multiple (2 or more) types of movement No unique subtypes are recognized here; many possible Option: name the main movement types (e.g., a Complex Rock Spread-Debris Flow Landslide)

Dominant Material

Consolidated:

(Bedrock)

Bedrock masses 

dominant

rockfall rock 

topple

rotational rock 

slide

(e.g., Toreva block)

translational rock 

slide

(=planar slide)

(e.g., block glide)

rock spread

block spread

rock fragment flow

(e.g., rockfall 

avalanche 

=sturzstrom)

Unconsolidated:

Coarser

Coarse fragments 

dominant

debris

fall

debris 

topple

rotational debris 

slide

<------------ debris slide ------------>

translational debris 

slide

debris spread debris avalanche

(drier, steep slope)

debris flow (wetter)

(e.g., lahar)

Finer

Fine earth particles 

dominant

earth fall

(=soil fall)

earth 

topple

(=soil 

topple)

rotational earth 

slide

translational earth 

slide

earth spread

(e.g., sand boil)

earth flow

(e.g., creep, loess 

flow, mudflow, 

sandflow, solifluction)

* Slides, especially rotational slides, are commonly and imprecisely called “slumps.”

(Schoeneberger and Wysocki, 2000; developed from Cruden and Varnes, 1996)
USDA-NRCS 5–9 September 2012

NORTH AMERICAN GEOLOGIC TIME SCALE 1, 2 ERA

Geologic 

Period

Geologic 

Epoch

SubdivisionOxygen 

Isotope 

Stage

Years (BP)

CENOZOIC

QUATERNARY

Holocene (1) 0 to 10-12 ka*

Late 

Pleistocene

Late 

Wisconsin

(2) 10-12 to 28 ka

Middle 

Wisconsin

(3, 4) 28 to 71 ka

Early 

Wisconsin

Late

Sangamon

(5a - 5d) 71 to 115 ka

Sangamon (5e) 115 to128 ka

Pleistocene

Late Middle 

Pleistocene 

(Illinoian)

(6 - 8) 128 to 300 ka

Middle 

Pleistocene

Middle 

Pleistocene

(9 - 15) 300 to 620 ka

Early Middle 

Pleistocene

(16 - 19) 620 to 770 ka

Early 

Pleistocene

770 ka to

2.6 Ma**

TERTIARY

Neogene

Pliocene 2.6 to 5.3 Ma

Miocene 5.3 to 23.0 Ma

Paleogene

Oligocene 23.0 to 33.9 Ma

Eocene 33.9 to 55.8 Ma

Paleocene 55.8 to 65.5 Ma

MESOZOICCRETACEOUS

Late Cretaceous 65.5 to 99.6 Ma

Early Cretaceous 99.6 to 145.5 Ma

JURASSIC 145.5 to 201.6 Ma

TRIASSIC 201.6 to 251.0 Ma

PALEOZOIC

PERMIAN 251.0 to 299.0 Ma

PENNSYLVANIAN 299.0 to 318.0 Ma

MISSISSIPPIAN 318.0 to 359.0 Ma

DEVONIAN 359.0 to 416.0 Ma

SILURIAN 416.0 to 444.0 Ma

ORDIVICIAN 444.0 to 488.0 Ma

CAMBRIAN 488.0 to ≈ 542.0 Ma

PRECAMBRIAN ERA > 542.0 Ma
USDA-NRCS 5–10 September 2012

*ka = x 1,000 ** Ma = x 1,000,000 (≈ = approximately)

1 Modified from Morrison, 1991; Sibrava et al., 1986; and Harland 

et al., 1990.

2 Modified from Walker and Geissman, 2009.

TILL TERMS

Genetic classification and relationships of till terms commonly used 

in soil survey (Schoeneberger and Wysocki, 2000; adapted from 

Goldthwaite and Matsch, 1988).

Location (Facies 

of tills grouped by 

position at time of 

deposition)

Till Types

Terrestrial Waterlaid

Proglacial Till

(at the front of or in 

front of glacier)

proglacial flow till waterlaid flow till

Supraglacial Till

(on top of or within 

upper part of 

glacier)

supraglacial flow till 1, 3

supraglacial melt-out till 1

(ablation till—NP) 1

(lowered till—NP) 2

(sublimation till—NP) 2

—

Subglacial Till

(within the lower 

part of or beneath 

glacier)

lodgment till 1

subglacial melt-out till

subglacial flow till

(= “squeeze till” 2, 3)

(basal till—NP) 1

(deformation till—NP) 2

(gravity flow till—NP) 2

waterlaid melt-out till

waterlaid flow till

iceberg till

(= “ice-rafted”)

1 Ablation till and basal till are generic terms that only describe 

“relative position” of deposition and have been widely replaced 

by more specific terms that convey both relative position 

and process. Ablation till (any comparatively permeable 

debris deposited within or above stagnant ice) is replaced by 

supraglacial melt-out till, supraglacial flow till, etc. Basal till (any 

dense, nonsorted subglacial till) is replaced by lodgment till, 

subglacial melt-out till, subglacial flow till, etc.

2 Additional (proposed) till terms that are outdated or have not 

gained wide acceptance and are considered to be Not Preferred

and should not be used.

3 Also called gravity flow till (not preferred).
USDA-NRCS 5–11 September 2012

PYROCLASTIC TERMS

(Schoeneberger and Wysocki, 2002)

Pyroclasts and Pyroclastic Deposits (Unconsolidated)

Size Scale:

0.062 mm 1 2 mm 64 mm 1

<----------------------------------- tephra ----------------------------------->

(all ejecta)

<------------ ash 1 ------------> <--- cinders 2 --->

(specific gravity

>1.0 and <2.0)

<--- bombs 1 --->

(fluid-shaped <----------> coarse fragments) fine ash 1

<-------------->

coarse ash 1

<---- lapilli 1 ---->

(specific gravity 

>2.0)

<--- blocks 1 --->

(angular-shaped 

coarse fragments)

<--------------- scoria 2 ---------------->

(slightly or moderately vesicular;

specific gravity >2.0)

<-------------->

pumiceous 

ash 3

<----------------- pumice ---------------->

(highly vesicular;

specific gravity <1.0)

Associated Lithified (Consolidated) Rock Types

<---------->

fine tuff 1

<-------------->

coarse tuff 1

<- lapillistone 1 ->

(sp. gravity >2.0)

<------------------>

pyroclastic 

breccia

<------- welded tuff 1 -------> <------------ agglomerate 1 ----------->

(rounded, volcanic coarse fragments)

<-------- ignimbrite -------->

(consolidated ash flows and 

nuee ardentes)

<--------- volcanic breccia 1 ---------->

(angular, volcanic coarse fragments)

1 These size breaks are taken from geologic literature (Fisher, 

2005) and based on the modified Wentworth scale. The 0.062-

mm break is very close to the USDA’s 0.05-mm break between 

coarse silt and very fine sand (Soil Survey Division Staff, 1993). 

The 64-mm break is relatively close to the USDA’s 76-mm 

break between coarse gravel and cobbles. (See “Comparison of 

Particle Size Classes in Different Systems” in the “Profile/Pedon 

Description” on p. 2–45.)

2 A lower size limit of 2 mm is required in soil taxonomy (Soil 

Survey Staff, 1994; p. 54) but is not required in geologic usage 

(Fisher, 2005).
USDA-NRCS 5–12 September 2012

3 The descriptor for pumice particles <2 mm, as used in soil 

taxonomy (Soil Survey Staff, 1999). Geologic usage does not

recognize any size restrictions for pumice.

HIERARCHICAL RANK OF LITHOSTRATIGRAPHIC 

UNITS 1, 2, 3

Supergroup—The broadest lithostratigraphic unit. A supergroup 

is an assemblage of related, superposed groups, or groups and 

formations. Supergroups are most useful in regional or broad scale 

synthesis.

Group—The lithostratigraphic unit next in rank below a 

supergroup. A group is a named assemblage of related 

superposed formations, which may include unnamed 

formations. Groups are useful for small-scale (broad) mapping 

and regional stratigraphic analysis.

Formation (called Geologic Formation in NASIS)—The 

basic lithostratigraphic unit used to describe, delimit, and 

interpret sedimentary, extrusive igneous, metavolcanic, 

and metasedimentary rock bodies (excludes metamorphic 

and intrusive igneous rocks) based on lithic characteristics 

and stratigraphic position. A formation is commonly, but 

not necessarily, tabular and stratified and is of sufficient 

extent to be mappable at the earth’s surface or traceable 

in the subsurface at conventional map scales.

(Formations can be, but are not necessarily, combined 

to form higher rank units [groups and supergroups] or 

subdivided into lower rank units [members or beds].)

Member—The formal lithostratigraphic unit next 

in rank below a formation and always part of a 

formation. A formation need not be divided selectively 

or entirely into members. A member may extend 

laterally from one formation to another.

Specifically defined types of members:

Lens (or Lentil): A geographically restricted member 

that terminates on all sides within a formation.

Tongue: A wedge-shaped member that extends 

beyond the main formation boundary or that wedges 

or pinches out within another formation.

Bed—The smallest formal lithostratigraphic unit 

of sedimentary rock. A bed is a subdivision of a 

member based upon distinctive characteristics 

and/or economic value (e.g., coal bed). Members 
USDA-NRCS 5–13 September 2012

need not be divided selectively or entirely into 

beds.

Flow—The smallest formal lithostratigraphic unit 

of volcanic rock. A flow is a discrete, extrusive, 

volcanic body distinguishable by texture, 

composition, superposition, and other criteria.

1 Lithostratigraphic units are mappable rock or sediment bodies 

that conform to the Law of Superposition (Article 2, Section A).

2 Separate data element (text field) in NASIS.

3 Adapted from North American Stratigraphic Code (North 

American Commission on Stratigraphic Nomenclature, 1983).

REFERENCES

Cruden, D.M., and D.J. Varnes. 1996. Landslide types and 

processes. In A.K. Turner and R.L. Schuster (ed.) Landslides: 

Investigation and mitigation. Spec. Rep. 247, Transportation 

Research Board, National Research Council. National Academy 

Press, Washington, DC.

Fisher, R.V. (updated by T. Frost) 2005. Pyroclastic sediments and 

rocks. AGI data sheet 6.3. In J.D. Walker and H.A. Cohen (ed). The 

geoscience handbook. AGI data sheets, 4th ed. Am. Geol. Inst., 

Alexandria, VA.

Goldthwaite, R.P., and C.L. Matsch (ed.) 1988. Genetic classification 

of glacigenic deposits: Final report of the commission on genesis 

and lithology of glacial Quaternary deposits of the International 

Union for Quaternary Research (INQUA). A.A. Balkema, Rotterdam.

Harland, W.B., R.L. Armstrong, L.E. Craig, A.G. Smith, and D.G. 

Smith. 1990. A geologic time scale. Press Syndicate of University of 

Cambridge, Cambridge, UK. 1 sheet.

Jackson, J.A. (ed.) 1997. Glossary of geology, 4th ed. Am. Geol. 

Inst., Alexandria, VA.

Morrison, R.B. (ed.) 1991. Quaternary nonglacial geology: 

Conterminous United States. Geol. Soc. Am., Decade of North 

American Geology, Geology of North America, vol. K–2.

Neuendorf, K., J.P. Mehl, and J.A. Jackson. 2005. Glossary of 

geology, 5th ed. Am. Geol. Inst., Alexandria, VA.

North American Commission on Stratigraphic Nomenclature. 1983. 

North American stratigraphic code. Am. Assoc. Petrol. Geol. Bull. 

67:841–875.
USDA-NRCS 5–14 September 2012

Schoeneberger, P.J., and D.A. Wysocki. 1998. Personal 

communication. USDA, NRCS, National Soil Survey Center, Lincoln, 

NE.

Schoeneberger, P.J., and D.A. Wysocki. 2000. Personal 

communication. USDA, NRCS, National Soil Survey Center, Lincoln, 

NE.

Schoeneberger, P.J., and D.A. Wysocki. 2002. Personal 

communication. USDA, NRCS, National Soil Survey Center, Lincoln, 

NE.

Sibrava, V., D.Q. Bowen, and D.Q. Richmond (ed.) 1986. 

Quaternary glaciations in the Northern Hemisphere: Final report 

of the International Geological Correlation Programme, Project 24. 

Quaternary Sci. Rev., Vol. 5. Pergamon Press, Oxford.

Soil Survey Division Staff. 1993. Soil survey manual. USDA, SCS, 

Agric. Handb. 18. U.S. Gov. Print. Office, Washington, DC.

Soil Survey Staff. 1994. Keys to soil taxonomy, 6th ed. USDA, SCS. 

Pocohantas Press, Inc., Blacksburg, VA.

Soil Survey Staff. 1999. Soil taxonomy, 2nd ed. USDA, NRCS, Agric. 

Handb. 436. U.S. Gov. Print. Office, Washington, DC.

Soil Survey Staff. 2011. Soil survey laboratory information manual. 

Soil Surv. Invest. Rep. 45, ver. 2.0. USDA, NRCS, National Soil 

Survey Center, Lincoln, NE (ftp://ftp-fc.sc.egov.usda.gov/NSSC/

Lab_Info_Manual/SSIR_45.pdf)

Soil Survey Staff. 2012. Glossary of landform and geologic terms. 

Part 629, National soil survey handbook (NSSH) [Online]. USDA, 

NRCS, National Soil Survey Center, Lincoln, NE.

Tennissen, A.C. 1974. Nature of earth materials. Prentice-Hall, Inc., 

Englewood Cliffs, NJ.

Walker, J.D., and J.W. Geissman. 2009. Geologic time scale. Geol. 

Soc. Am.
USDA-NRCS 6–1 September 2012

LOCATION

D.A. Wysocki, P.J. Schoeneberger, and E.C. Benham, NRCS, Lincoln, NE

GPS LOCATION

GEODETIC DATUM (Horizontal_datum_name in NASIS)—A 

geodetic datum must accompany latitude and longitude. A geodetic 

datum is a model that defines the earth’s shape and size and serves 

as a latitude, longitude reference. Geodetic datum is a selectable 

GPS parameter. The preferred datum is the World Geodetic System 

1984 (WGS-84).

Datum Name Code

American Samoa 1962

Astro Beacon “E” 1945

Astro Tern Island (FRIG)

Astronomical Station 1952

Bellevue (IGN)

Canton Astro 1966

Chatham Island Astro 1971

DOS 1968

Easter Island 1967

Geodetic Datum 1949

Guam 1963

Gux 1 Astro

Johnston Island 1961

Kusaie Astro 1961

Luzon

Midway Astro 1961

North American Datum of 1927 NAD27

North American Datum of 1983 1 NAD83

Old Hawaiian

Pitcairn Astro 1967

Santo (DOS) 1965

Viti Levu 1916

Wake Island Astro 1952

Wake-Eniwetok 1960

World Geodetic System 1984 1 WGS84

1 Preferred datum method for continental U.S.
USDA-NRCS 6–2 September 2012

PUBLIC LAND SURVEY

The Public Land Survey System (PLSS) is a rectangular method for 

describing and subdividing land in the U.S. The PLSS process first 

establishes two controlling survey lines for a large tract: an eastwest base line and a north-south principal meridian, which intersect 

at an initial point. Thompson (1987; p. 82–83) shows base lines 

and principal meridians for the conterminous U.S. Lines parallel 

(standard parallels) to the base line are established at 24- or 

30-mile intervals. The meridian, baseline, and standard parallels 

form a lattice for further subdivision. Subsequent survey divides 

land into townships of 36 square miles (6 miles on a side). Each 

township is subdivided into 36 sections 1 mile square (640 acres). 

Each section is further subdivided into quarter-sections (160 acres).

PLSS Principal Meridians

Black Hills New Mexico Principal

Boise Ohio Company Purchase

Chickasaw Ohio River

Choctaw Principal

Cimarron Salt Lake

Connecticut Western Reserve San Bernardino

Copper River Second Principal

Fairbanks Second Scioto River

Fifth Principal Seward

First Principal Sixth Principal

First Scioto River St. Helena

Fourth Principal St. Stephens

Fourth Principal Extended Tallahassee

Gila and Salt River Third Principal

Great Miami River Third Scioto River

Humboldt Twelve-Mile Square

Huntsville U.S. Military

Indian Uintah

Kateel River Umiat

Louisiana Ute

Michigan Washington

Mount Diablo West of the Great Miami

Muskingum River Willamette

Navajo Wind River

Prior to the GPS, soil descriptions predominantly used the PLSS 

for location. Land survey in certain States predates the PLSS and 

commonly employs the State Plane Coordinate System for location 

description. These States include Connecticut, Delaware, Georgia, 
USDA-NRCS 6–3 September 2012

Kentucky, Maine, Maryland, Massachusetts, New Hampshire, New 

Jersey, New York, North Carolina, Ohio (parts), Pennsylvania, Rhode 

Island, South Carolina, Tennessee, Texas, Vermont, Virginia, and 

West Virginia (see State Plane Coordinate System, p. 6–7). 

In soil survey, the base line and principal meridian are generally not 

recorded. Instead, the name of the appropriate USGS topographic 

7.5-minute or 15-minute quadrangle is recorded; e.g., Pleasant 

Dale, NE, 7.5 min. Quad.

TOWNSHIPS and RANGES—Each township is identified using 

two indexes: 1) Township or Tier (north-south number relative 

to the base line), and 2) Range (east-west number relative to the 

Principal Meridian). For example, a township is described as T2N, 

R4E for second township row north of the base line and fourth range 

row east of the prime meridian.

36 mi2

6 mi

6 mi

Township

lines

Principal Meridian

Base Line

Local Point

of Origin 

Section

= 1 mi2

31 32 33 35 36

30 29 28 27 26 25

19 20 21 22 23 24

18 17 16 15 14 13

7 8 9 10 11 12

6 5 4 3 2 1

Section 34

of T1S-R2E

34

Township 2 South,

Range 1 West

Township 3 North,

Range 2 West

R2W R1W R1E R2E R3E

T3N

T2N

T1N

T1S

T2S

R2W R1W R1E R2E R3E

T2S

T1S

T1N

T2N

T3N

(Modified from Mozola, 1989)

N

SECTIONS—Each 1-square-mile section is numbered sequentially 

starting with 1 in the northeast corner of a township proceeding 

in east-west rows, wrapping back and forth to fill in the township; 

e.g., Section 34, T1S, R2E (Section 34 of Township 1 South, Range 

2 East). 
USDA-NRCS 6–4 September 2012

NOTE: Due to the earth’s curvature, survey error, or joins to other 

survey systems (e.g., Metes and Bounds), occasional irregularities 

occur in grid areas. Survey adjustments can result in nonstandard 

size sections and/or breaks in the usual section number sequence.

SECTION SUBDIVISIONS—The PLSS subdivides sections into 

half- and quarter-sections. The section area fraction (1/2, 1/4) is 

combined with the compass quadrant that the area occupies in a 

section; e.g., SW 1/4, Section 34, T1S, R2E (southwest quarter of 

section 34, township 1 south, range 2 east). Additional subdivisions, 

by halves and quarters, describe progressively smaller areas. The 

land description is presented consecutively beginning with the 

smallest subdivision; e.g., a 20-acre parcel described as N 1/2, NW 

1/4, SW 1/4, NW 1/4 of Section 34, T1S, R2E (north half of the 

northwest quarter of the southwest quarter of the northwest quarter 

of section 34, township 1 south, range 2 east). 

NOTE: Point locations (e.g., soil pits) using the PLSS were 

traditionally measured in English units with reference to a specified 
USDA-NRCS 6–5 September 2012

section corner or quarter-corner (1/4 post); e.g., 660 feet east and 

1320 feet north of the southwest corner post, Section 34, T1S, R2E.

UNIVERSAL TRANSVERSE MERCATOR (UTM) 

RECTANGULAR COORDINATE SYSTEM

The Universal Transverse Mercator coordinate system (UTM) is an 

international reference (military and civilian) that depicts the earth’s 

three-dimensional surface in a relatively accurate, two-dimensional, 

flat plane and uses Cartesian coordinates (meters) for location. 

The U.S. Army began use of the UTM projection and grid system 

in 1947. GPS units can display UTM coordinates, which are simpler 

for map distance plotting and measurement than latitude and 

longitude. 

The UTM grid spans from 80 ̊S through 84 ̊N latitude (the Universal 

Polar Stereographic [UPS] system covers polar areas). The UTM 

system divides the earth into 60 equally spaced, vertically arranged 

planes known as zones, or world zones; each zone spans 6 degrees 

of longitude. The zones are sequentially numbered 1 through 60 

west to east. Zone numbering begins at 180 degrees longitude, the 

International Date Line. UTM zone 1 encompasses 180–174 degrees 

W longitude, zone 2 spans 174–168 W longitude, and so forth 

through zone 60.

The UTM grid system also divides the earth into 20 equally spaced 

east-west rows. Each row circles the globe and spans exactly 8 

latitude degrees, except for the 12-degree-wide row between 

72 and 84 degrees north latitude. The 20 UTM rows are lettered 

C through X from south to north beginning at 80 degrees south 

latitude; I and O are omitted to avoid confusion with numbers. Row 

C spans 80–72 degrees south latitude, row D encompasses 72–64 

degrees south latitude, and so forth. The southern hemisphere 

contains rows C, D, E, F, G, H, J, K, L, and M, whereas the northern 

hemisphere contains rows N, P, Q, R, S, T, U, V, W, and X. 

The central meridian of each zone is the east-west control for UTM 

coordinates, and other N-S grid lines are parallel to the central 

meridian. UTM coordinates are expressed as a distance in meters 

east of a zone’s central meridian. This value is called an “easting.” 

The central meridian by convention is given a value of 500,000 m 

east; this eliminates negative distance values. A location west of the 

central meridian has a value <500,000 m. Easting values can range 

from 166,000 to 834,000 m. Some protocols give the easting value 

a leading zero (e.g., 0166000).

The initial north-south grid line for the northern hemisphere is the 

Equator, which has a value of 0 m. A UTM value called a “northing” 

is expressed as distance in meters north of the Equator. For the 

northern hemisphere, northings range from 0 to 9,328,000 m (84 

N Lat). In the southern hemisphere, the 0 m reference is the South 
USDA-NRCS 6–6 September 2012

Pole; the northing is expressed as distance in meters north of it. 

The range in northings is 1,118,000 (80 S Lat) to 10,000,000 m 

(Equator). Points on the Equator can be described by either the 

north or south reference.

A complete UTM location gives in order the zone number, row letter, 

easting value, and northing value; for example, 16 T, 0313702 m 

E, 4922401 m N. The row letters designate the hemisphere location 

(northern or southern). 

All quadrangle maps prepared by the USGS show the UTM 

coordinates (Snyder, 1987). On 7.5-minute quadrangle maps 

(1:24,000 and 1:25,000 scale) and 15-minute quadrangle maps 

(1:50,000, 1:62,500, and standard edition 1:63,360 scales), the 

UTM grid lines are indicated at 1,000-meter intervals, either by blue 

ticks in the map margin or with full grid lines. The maps display 

shortened 1,000-meter values at the tick or grid lines. The full 

meter values are shown only at ticks nearest the southeast and 

northwest map corners. 

To obtain a UTM grid location from a USGS map, use the grid lines, 

draw lines connecting corresponding ticks on opposite map edges, 

or place a transparent grid overlay on the map. Measure distance 

between any map point and the nearest grid line in cm. If the map 

scale is 1:24000, multiply the measured cm distance by 240 to 
USDA-NRCS 6–7 September 2012

obtain meters on the ground. The northing of a point is the value 

of the nearest grid line south plus its distance north of that line; 

the easting is the value of the nearest grid line west of it plus its 

distance east of that line. On maps at 1:100,000 and 1:250,000 

scale, a full UTM grid is shown at intervals of 10,000 meters and 

is numbered and used in the same way. Various overlay UTM 

templates that facilitate distance and coordinate measurement from 

topographic maps are commercially available.

STATE PLANE COORDINATE SYSTEM

The State Plane Coordinate System (SPCS) is designed for mapping 

and surveying in the U.S. It was developed in the 1930s by the 

U.S. Coast and Geodetic Survey. Historically, soil description 

locations sometimes used the SPCS system where the PLSS is 

nonexistent. The States that have used this system are Connecticut, 

Delaware, Georgia, Kentucky, Maine, Maryland, Massachusetts, New 

Hampshire, New Jersey, New York, North Carolina, Ohio (parts), 

Pennsylvania, Rhode Island, South Carolina, Tennessee, Texas, 

Vermont, Virginia, and West Virginia. 

The SPCS divides all 50 states of the United States, Puerto Rico, 

and the U.S. Virgin Islands into 120 numbered zones. The zones 

correspond to political boundaries (State and most counties). The 

SPCS establishes a separate coordinate system and two Principal 

lines in each State: a north-south line and an east-west line. USGS 

7.5-minute topographic maps indicate SPCS grids by tick marks 

along the neatlines (outer border). NOTE: Older topo maps based 

on NAD27 have grid units in feet. After adoption of NAD83, meters 

become the grid unit. 

Specific location coordinates are described by distance and primary 

compass direction (north [northing], south [southing], east 

[easting], or west [westing]) relative to the Principal lines; e.g., 

10,240 m easting and 1,234 m northing. 

Contact the NRCS State office or the Regional Soil Survey MLRA 

Office for State-specific details.

REFERENCES

Mozola, A.J. 1989. U.S. public land survey. In J.T. Dutro et al., AGI 

data sheets, 3rd ed. Am. Geol. Inst., United Book Press, Inc.

Snyder, J.P. 1987. Map projections—A working manual. U.S. Geol. 

Surv. Prof. Pap. 1395. U.S. Gov. Print. Office, Washington, DC.

Thompson, M.M. 1987. Maps for America, 3rd ed. U.S. Geol. Surv., 

U.S. Dep. Interior. U.S. Gov. Print. Office, Washington, DC.

USDA-NRCS 7–1 September 2012

MISCELLANEOUS

D.A. Wysocki, P.J. Schoeneberger, and E.C. Benham, NRCS, Lincoln, NE

PERCENT OF AREA COVERED

The following graphics are Area Percent Covered used to describe 

“Amount” or “Quantity.” (NOTE: Within each large box [e.g., 2%], 

a quadrant contains the same total area covered but contains 

different object sizes and numbers.)

2%
USDA-NRCS 7–2 September 2012

5%

10%
USDA-NRCS 7–3 September 2012

15%

20%
USDA-NRCS 7–4 September 2012

25%

30%
USDA-NRCS 7–5 September 2012

35%

40%
USDA-NRCS 7–6 September 2012

45%

50%
USDA-NRCS 7–7 September 2012

60%

70%
USDA-NRCS 7–8 September 2012

75%

80%
USDA-NRCS 7–9 September 2012

90%
USDA-NRCS 7–10 September 2012

KSAT CLASS ESTIMATE

Field Ksat is an important soil property and its measurement is 

greatly preferred over laboratory determined or mathematically 

predicted Ksat values. Field Ksat reflects horizon, pedon, and largerscale macropore networks that strongly influence water flow in 

soilscapes. Various methods exist for field Ksat measurement (Soil 

Survey Staff, 1982; Bouma et al., 1982; Amoozegar and Warrick, 

1986; Soil Survey Staff, 2009).

Where measured Ksat values are unavailable, mathematical 

models or predictions can provide approximate estimates. Such 

Ksat estimates rely on other estimated or measured soil physical 

properties (e.g., texture, bulk density, porosity). Estimated Ksat

values are assigned as a class range to compare soils and are not 

used as a Ksat value for a specific site (Soil Survey Division Staff, 

1993).

A general guide for estimating Ksat classes (Soil Survey Staff 2012; 

Rawls and Brakensiek, 1983) involves a set of textural triangles that 

group soils by relative bulk density (low, medium, or high) and soil 

texture. Use the following charts and steps to predict Ksat by class 

range. 

Step 1 - Use an estimated or known bulk density and texture 

to select the appropriate bulk density triangle for the layer. 

[e.g., a clay loam (35% sand and 35% clay) with a 1.4 g cm-3

bulk density fits the Medium Bulk Density triangle].

Step 2 - Use the appropriate Bulk Density / Ksat Class Triangle

to assign a Ksat class. [e.g., a clay loam texture (35% clay and 

35% sand) with medium bulk density assigns an estimated 

Moderately Low (0.1 – 1.0 μm/sec) Ksat Class].
USDA-NRCS 7–11 September 2012
USDA-NRCS 7–12 September 2012
USDA-NRCS 7–13 September 2012
USDA-NRCS 7–14 September 2012

SOIL WATER REPELLENCY (DISCUSSION)

Water repellency is a soil’s ability to resist spontaneous wetting 

when water is placed on a soil surface. Water-repellent compounds 

arise from organic matter decomposition, including plant root 

exudates, fungal processes, and surface waxes from plant leaves 

(Mainwaring et al., 2004). Initial, irreversible drying of organic 

materials (Hallett et al., 2003) causes hydrophilic functional groups 

to strongly bond with each other and soil particles. This process 

results in an exposed water-repellent surface (Dekker et al., 1998). 

Soil water repellency is a dynamic property that varies with climate, 

plant community, and microbial decomposition pathways. Fire is 

also an important factor; heat volatilizes water-repellent organic 

substances that move and condense where soil is cooler (Savage, 

1974). Fire may have a 3- to 5-year influence on water repellency 

(DeBano and Krammes, 1966). Water repellency decreases water 

infiltration and increases surface runoff and soil erodibility.

Organic compounds, particularly fats, waxes, and resins, form 

repellent coatings on mineral grains. The repellency degree depends 

on the quantity of particles covered (Doerr et al., 2006). Sandy soils 

(with low surface area) are more prone to water repellency than are 

loamy or clayey soils. Soil water repellency is spatially variable both 

laterally and with depth (Robichand and Miller, 1999; Hubbert et al., 

2006). Soil moisture content strongly influences water repellency. 

Soils that are more than about 10% moisture wet more readily than 

dry soils (Hubbert and Oriol, 2005; MacDonald and Huffman, 2004). 

A common technique to assess water repellency is the Water Drop 

Penetration Test (WDPT). A water drop is placed on a clean soil 

surface and the absorption time recorded (Letey, 1969). The WDPT 

test measures repellency persistence (Doerr et al., 2000). Water 

may penetrate instantly or take hours. Various time classifications 

relate water repellency to absorption time (Robichand et al., 2008). 

Such classifications have convenient intervals that allow relative 

comparison, but the times do not have intrinsic physical meaning. 
USDA-NRCS 7–15 September 2012

SOIL WATER REPELLENCY

Evaluate and record the relative soil water repellency determined 

from a Water Drop Penetration Time (WDPT) measurement. 

(NOTE: Soil should be in a dry state.)

WDPT PROCEDURE

1) Prepare with a knife or trowel a clean, level horizontal 15 x 

15 cm area of soil at a desired depth.

2) Use an eyedropper or plastic squeeze bottle to randomly 

place 5 drops of distilled water (approximately 5 mm in 

diameter) from a 1-cm height onto the prepared surface.

3) Record the average time (in seconds) that the drops remain 

on the surface before absorption. 

Determine the relative water repellency class according to the 

following table.

Relative Water 

Repellency Class Code Absorption Time (seconds)

Non-Water Repellent NWR 0 to 5

Slightly Water Repellent SWR > 5 to 60

Moderately Water Repellent MWR > 60 to 180

Strongly Water Repellent TWR > 180

Modified from Robichand, 2008.
USDA-NRCS 7–16 September 2012

MEASUREMENT EQUIVALENTS AND CONVERSIONS

METRIC TO ENGLISH

Known Symbol Multiplier Product Symbol

LENGTH

micrometers (microns) μm 3.9370 inches in or "

(=10,000 Angstrom units) x 10-5

millimeters mm 0.03937 inches in or "

centimeters cm 0.0328 feet ft or '

centimeters cm 0.3937 inches in or "

meters m 3.2808 feet ft or '

meters m 1.0936 yards yd

kilometers km 0.6214 miles (statute) mi

AREA

square centimeters cm2 0.1550 square inches in2

square meters m2 10.7639 square feet ft2

square meters m2 1.1960 square yards yd2

square kilometers km2 0.3861 square miles mi2

hectares ha 2.471 acres ac

VOLUME

cubic centimeters cm3 0.06102 cubic inches in3

cubic meters m3 35.3146 cubic feet ft3

cubic meters m3 1.3079 cubic yards yd3

cubic meters m3 0.0008107 acre-feet

(=43,560 ft3) acre-ft

cubic kilometers km3 0.2399 cubic miles mi3

liters (=1000 cm) l 1.0567 quarts (U.S.) qt

liters l 0.2642 gallons (U.S.) gal

milliliter ml 0.0338 fluid ounces oz

1 milliliter=1 cm3=1 gm (H20, at 25 °C)

MASS

grams g 0.03527 ounces (avdp.) oz

kilograms kg 2.2046 pounds (avdp.) lb

megagrams

(= metric tons) Mg 1.1023 short tons (2000 lb)

megagrams Mg 0.9842 long tons (2240 lb)
USDA-NRCS 7–17 September 2012

ENGLISH TO METRIC

Known Symbol Multiplier Product Symbol

LENGTH

inches in or " 2.54 x 104 micrometers (microns) μm

[=10,000 Angstrom units (A)]

inches in or " 2.54 centimeters cm

feet ft or ' 30.48 centimeters cm

feet ft or ' 0.3048 meters m

yards yd 0.9144 meters m

miles (statute) mi 1.6093 kilometers km

AREA

square inches in2 6.4516 square centimeters cm2

square feet ft2 0.0929 square meters m2

square yards yd2 0.8361 square meters m2

square miles mi2 2.59 square kilometers km2

acres ac 0.405 hectares ha

VOLUME

acre-feet acre-ft 1233.5019 cubic meters m3

acre-furrow-slice afs =6-in.-thick layer that’s 1 acre in area

≈ 2,000,000 lbs (assumes b.d.=1.3 g/cm3)

cubic inches in3 16.3871 cubic centimeters cm3

cubic feet ft3 0.02832 cubic meters m3

cubic yards yd3 0.7646 cubic meters m3

cubic miles mi3 4.1684 cubic kilometers km3

gallons (U.S.) gal 3.7854 liters l

(=0.8327 Imperial gal)

quarts (U.S.) qt 0.9463 liters (=1000 cm3) l

ounces oz 29.57 milliliters ml

1 milliliter=1 cm3=1 gm (H20, at 25 °C)

MASS

ounces (avdp.) oz 28.3495 grams g

ounces (avdp.) (1 troy oz.=0.083 lb)

pounds (avdp.) lb 0.4536 kilograms km

short tons (2000 lb) 0.9072 megagrams

(= metric tons) Mg

long tons (2240 lb) 1.0160 megagrams Mg
USDA-NRCS 7–18 September 2012

COMMON CONVERSION FACTORS

Known Symbol Multiplier Product Symbol

acres ac 0.405 hectares ha

acre-feet acre-ft 1233.5019 cubic meters m3

acre-furrow-slice afs =6-in.-thick layer that’s 1 acre square

≈ 2,000,000 lbs (assumes b.d.=1.3 g/cm3)

Angstrom units A 1x 10-8 centimeters cm

Angstrom units A 1x 10-4 micrometers um

Atmospheres atm 1.0133 x 106 dynes/cm2

Atmospheres atm 760 mm of mercury (Hg)

BTU (mean) BTU 777.98 foot-pounds

centimeters cm 0.0328 feet ft or '

centimeters cm 0.3937 inches in or "

centimeters/hour cm/hr 0.3937 inches/hour in/hr

centimeters/second cm/s 1.9685 feet/minute ft/min

centimeters/second cm/s 0.0224 miles/hour mph

chain (U.S.) 66 feet ft

chain (U.S.) 4 rods

cubic centimeters cm3 0.06102 cubic inches in3

cubic centimeters cm3 2.6417 x 10-4 gallons (U.S.) gal

cubic centimeters cm3 0.999972 milliliters ml

cubic centimeters cm3 0.0338 ounces (U.S.) oz

cubic feet ft3 0.02832 cubic meters m3

cubic feet

(H2O, 60 °F) ft3 62.37 pounds lbs

cubic feet ft3 0.03704 cubic yards yd3

cubic inches in3 16.3871 cubic centimeters cm3

cubic kilometers km3 0.2399 cubic miles mi3

cubic meters m3 35.3146 cubic feet ft3

cubic meters m3 1.3079 cubic yards yd3

cubic meters m3 0.0008107 acre-feet

(=43,560 ft3) acre-ft

cubic miles mi3 4.1684 cubic kilometers km3

cubic yards yd3 0.7646 cubic meters m3

degrees (angle) ° 0.0028 circumfrences

Faradays 96500 coulombs (abs)

fathoms 6 feet ft
USDA-NRCS 7–19 September 2012

Known Symbol Multiplier Product Symbol

feet ft or ' 30.4801 centimeters cm

feet ft or ' 0.3048 meters m

feet ft or ' 0.0152 chains (U.S.)

feet ft or ' 0.0606 rods (U.S.)

foot pounds 0.0012854 BTU (mean) BTU

gallons (U.S.) gal 3.7854 liters l

gallons (U.S.) gal 0.8327 Imperial gallons

gallons (U.S.) gal 0.1337 cubic feet ft3

gallons (U.S.) gal 128 ounces (U.S.) oz

grams g 0.03527 ounces (avdp.) oz

hectares ha 2.471 acres ac

horsepower 2545.08 BTU (mean)/hour

inches in or " 2.54 x 104 micrometers (micron) μm

(=10,000 Angstrom units [A])

inches in or " 2.5400 centimeters cm

inches/hour in/hr 2.5400 centimeters/hour cm/hr

inches/hour in/hr 7.0572 micrometers/sec μm/sec

kilograms kg 2.2046 pounds (avdp.) lb

kilometers km 0.6214 miles (statute) mi

joules J 1 x 107 ergs

liters l 0.2642 gallons (U.S.) gal

liters l 33.8143 ounces oz

liters (=1000 cm3) l 1.0567 quarts (U.S.) qt

long tons (2240 lb) 1.0160 megagrams Mg

megagrams

(= metric tons) Mg 1.1023 short tons (2000 lb)

megagrams Mg 0.9842 long tons (2240 lb)

meters m 3.2808 feet ft or '

meters m 39.37 inches in

micrometers

(microns) μm 1.000 microns μ

micrometers/second μm/sec 0.1417 inches/hour in/hr

micron μ 1 x 10-4 centimeters cm

microns μ 3.9370 inches in or "
USDA-NRCS 7–20 September 2012

Known Symbol Multiplier Product Symbol

(=10,000 Angstrom units) x 10-5

micron μ 1.000 micrometer μm

miles (statute) mi 1.6093 kilometers km

miles/hour mph 44.7041 cent./second cm/s

miles/hour mph 1.4667 feet/second ft/s

milliliter ml 0.0338 fluid ounces oz

1 milliliter ≈ 1 cm3=1 gm (H2O, at 25°C)

milliliter ml 1.000028 cubic centimeters cm3

millimeters mm 0.03937 inches in or "

ounces oz 29.5729 milliliters ml

1 milliliter ≈ 1 cm3=1 gm (H2O, at 25 °C)

ounces (avdp.) oz 28.3495 grams g

ounces (avdp.) 1 troy oz.=0.083 lb

pints (U.S.) pt 473.179 cubic centimeters cm3

or cc

pints (U.S.) pt 0.4732 liters l

pounds (avdp.) lb 0.4536 kilograms kg

quarts (US liquid) qt 0.9463 liters (=1000 cm3) l

rods (U.S.) 0.25 chains (U.S.) ft

rods (U.S.) 16.5 feet (U.S.) ft

short tons (2000 lb) 0.9072 megagrams

(= metric tons) Mg

square centimeters cm2 0.1550 square inches in2

square feet ft2 0.0929 square meters m2

square inches in2 6.4516 sq. centimeters cm2

square kilometers km2 0.3861 square miles mi2

square meters m2 10.7639 square feet ft2

square meters m2 1.1960 square yards yd2

square miles mi2 2.5900 square kilometers km2

square yards yd2 0.8361 square meters m2

yards yd 0.9144 meters m
USDA-NRCS 7–21 September 2012

GUIDE TO MAP SCALES AND MINIMUM SIZE 

DELINEATIONS 1

Order 

of Soil 

Survey

Map Scale Inches 

Per Mile

Minimum Size 

Delineation 2

Acres Hectares

Order 1

1:500 126.7 0.0025 0.001

1:1,000 63.4 0.100 0.004

1:2,000 31.7 0.040 0.016

1:5,000 12.7 0.25 0.10

1:7,920 8.0 0.62 0.25

1:10,000 6.34 1.00 0.41

Order 2

1:12,000 5.28 1.43 0.6

1:15,840 4.00 2.50 1.0

1:20,000 3.17 4.00 1.6

1:24,000 3 2.64 5.7 2.3

Order 3 1:30,000 2.11 9.0 3.6

1:31,680 2.00 10.0 4.1

Order 4

1:60,000 1.05 36 14.5

1:62,500 4 1.01 39 15.8

1:63,360 1.00 40 16.2

Order 5

1:80,000 0.79 64 25.8

1:100,000 0.63 100 40

1:125,000 0.51 156 63

1:250,000 0.25 623 252

1:500,000 0.127 2,500 1,000

1:750,000 0.084 5,600 2,270

Very 

General

1:1,000,000 0.063 10,000 4,000

1:7,500,000 0.0084 560,000 227,000

1:15,000,000 0.0042 2,240,000 907,000

1 Modified from Peterson, 1981.

2 Traditionally, the minimum size delineation is assumed to 

be a 1/4-inch square, or a circle with an area of 1/16 inch2. 

Cartographically, this is about the smallest area in which a 

conventional soil map symbol can be legibly printed. Smaller 

areas can be, but rarely are, delineated and the symbol “lined in” 

from outside the delineation.

3 Corresponds to USGS 7.5-minute topographic quadrangle maps.

4 Corresponds to USGS 15-minute topographic quadrangle maps.
USDA-NRCS 7–22 September 2012

COMMON SOIL MAP SYMBOLS (TRADITIONAL)

(From Soil Survey Staff, 1990.) The following symbols are common 

on field sheets (original aerial photograph–based soil maps) and in 

many soil surveys published prior to 1997. Current guidelines for 

map compilation symbols are in NSSH, Exhibit 627-5, Feature and 

Symbol Legend for Soil Survey (Soil Survey Staff, 2012).

LANDFORM FEATURES

EXCAVATIONS

 

SOIL DELINEATIONS

ESCARPMENTS

 Bedrock

 Other than bedrock

SHORT STEEP SLOPE

GULLY

DEPRESSION, closed

SINKHOLE

Prominent hill or peak

Soil sample site

 (Type location, etc.)

 Borrow pit

 Gravel pit

 Mine or quarry

LANDFILL

FEATURE SYMBOL

(Points down slope)

(Points down slope)

S

BaC

MiA
USDA-NRCS 7–23 September 2012

MISCELLANEOUS SURFACE FEATURES

Blowout

Clay spot

Gravelly spot

Lava flow

Marsh or swamp

Rock outcrop (includes

sandstone and shale)

Saline spot

Sandy spot

Severely eroded spot

Slide or slip (tips point upslope)

Sodic spot

Spoil area

Stony spot

Very stony spot

Wet spot

FEATURE SYMBOL
USDA-NRCS 7–24 September 2012

79

79

345

ROAD EMBLEMS

CULTURAL FEATURES

Interstate

Federal

State

County, farm, or ranch

RAILROAD

POWER TRANSMISSION LINE

(normally not shown)

PIPELINE

(normally not shown)

FENCE

(normally not shown)

FEATURE SYMBOL

410

224 410

52

347 52

378
USDA-NRCS 7–25 September 2012

CULTURAL FEATURES (continued)

LEVEES

Without road

With road

With railroad

Single side slope

(showing actual feature location)

DAMS

Medium or small

Large

FEATURE SYMBOL

W
USDA-NRCS 7–26 September 2012

FLOOD

POOL

LINE

HYDROGRAPHIC FEATURES

STREAMS

Perennial, double line

(large)

Perennial, single line

(small)

Intermittent

Drainage end

or flow direction

SMALL LAKES, PONDS,

AND RESERVOIRS

Perennial water

Miscellaneous water

Flood pool line

Lake or pond

(perennial)

MISCELLANEOUS

WATER FEATURES

Spring

Well, artesian

Well, irrigation

FEATURE SYMBOL
USDA-NRCS 7–27 September 2012

MISCELLANEOUS CULTURAL FEATURES

Airport

Cemetery

Farmstead, house

(omit in urban areas)

Church

School

Other religion (label)

Located object (label)

Tank (label)

Lookout tower

Oil and/or natural gas wells

Windmill

Lighthouse

FEATURE SYMBOL

Mt.

Carmel

Ranger

Station

Petroleum
USDA-NRCS 7–28 September 2012

REFERENCES

Amoozegar, F. and A.W. Warrick. 1986. Hydraulic conductivity of 

saturated soils: Field methods. In A. Klute (ed). 1986. Methods of 

soil analysis part 1. Physical and mineralogical methods, 2nd ed. 

ASA, Agron. Mono. 9, Madison, WI, pp. 735-770. 

DeBano, L.F., and J.S. Krammes. 1966. Water repellent soils and 

their relation to wildfire temperatures. Int. Assoc. Sci. Hydrol. Bull., 

XI Annals 2, pp. 14-19.

DeBano, L.F. 1981. Water repellent soils: A state-of-the-art. Gen. 

Tech. Rpt. PSW-46. Berkeley, CA: USDA, Forest Service, Pacific 

Southwest Forest and Range Experiment Station. 21 p.

Dekker, L.W., C.J. Ritsema, K. Oostindie, and O.H. Boersma. 1998. 

Effect of drying temperature on the severity of soil water repellency. 

Soil Sci. 163:780-796.

Doerr, S.H., R.A. Shakesby, L.W. Dekker, and C.J. Ritsema. 2006. 

Occurrence prediction and hydrological effects of water repellency 

amongst major soil and land-use types in a humid temperate 

climate. Eur. J. Soil Sci. 57:741-754.

Hallett, P.D., D.C. Gordon, and A.G. Bengough. 2003. Plant 

influence on rhizosphere hydraulic properties: Direct measurements 

using a miniaturised infiltrometer. New Phytologist 157:597-603.

Hubbert, K.R., and V. Oriol. 2005. Temporal fluctuations in soil 

water repellency following wildfire in chaparral steeplands, southern 

California. Intern. J. Wildland Fire 14:439-447. 

Hubbert, K.R., H.K. Preisler, P.M. Wohlgemuth, R.C. Graham, and 

M.G. Narog. 2006. Prescribed burning effects on soil physical 

properties and soil water repellency in a steep chaparral watershed, 

southern California. U.S.A. Geoderma. 130:284-298.

Mainwaring, K.A., C.P. Morley, S.H. Doerr, P. Douglas, C.T. Llewellyn, 

G. Llewellyn, I. Matthews, and B.K. Stein. 2004. Role of heavy polar 

organic compounds for water repellency of sandy soils. Env. Chem. 

Letters 2:35-39.

Letey, J. 1969. Measurement of contact angle, water drop 

penetration time, and critical surface tension. Proceed. of the Symp. 

on Water-Repellent Soils, 6-10 May 1968, UC, Riverside, pp. 43-47.

Peterson, F.F. 1981. Landforms of the Basin and Range Province 

defined for soil survey. Nevada Agric. Exp. Stn. Tech. Bull. 28. Reno, 

NV.
USDA-NRCS 7–29 September 2012

Rawls, W.J., and D.L. Brakensiek. 1983. A procedure to predict 

Green and Ampt infiltration parameters. In Advances in infiltration. 

Proc. of the National Conf. on Advances in Infiltration, Dec. 12-13. 

Chicago, IL.

Robichaud, P.R., and S.M. Miller. 1999. Spatial interpolation and 

simulation of post-burn duff thickness after prescribed fire. Intern. 

J. Wildland Fire 9:137-143.

Robichaud, P.R., S.A. Lewis, and L.E. Ashmun. 2008. New procedure 

for sampling infiltration to assess post-fire soil water repellency. 

USDA, Forest Service, Rocky Mountain Research Station, Research 

Note RMRS-RN-33.

Savage, S.M. 1974. Mechanism of fire-induced water repellency in 

soil. Soil Sci. Soc. Amer. Proc. 38:652-657.

Soil Survey Division Staff. 1993. Soil survey manual. USDA, SCS, 

Agric. Handb. 18. U.S. Gov. Print. Office, Washington, DC. 

Soil Survey Staff. 1982. Measuring hydraulic conductivity for use in 

soil surveys. Soil Survey Investigations Report No. 38, USDA, SCS, 

National Soil Survey Center, Lincoln, NE. 

Soil Survey Staff. 1990. National soil survey handbook (NSSH), Title 

170, Part 601. USDA, NRCS, National Soil Survey Center, Lincoln, 

NE.

Soil Survey Staff. 2009. Soil survey field and laboratory methods 

manual. Soil Surv. Invest. Rep. 51, ver. 1.0. R. Burt (ed.) USDA, 

NRCS.

Soil Survey Staff. 2012. National soil survey handbook (NSSH) 

[online]. USDA, NRCS, National Soil Survey Center, Lincoln, NE.

(http://soils.usda.gov/technical/handbook/)

USDA-NRCS 8–1 September 2012

SOIL SAMPLING

P.J. Schoeneberger, D.A. Wysocki, and E.C. Benham, NRCS, Lincoln, NE

INTRODUCTION

Laboratory measurement of soil properties (e.g., particle size, 

organic carbon, etc.) requires sample collection. Two fundamental 

sampling requirements are: 1) appropriate site selection, and 2) 

a detailed soil description. Soils are landscape entities that reflect 

geomorphic, pedologic, and hydrologic processes and parent 

material distribution (Wysocki et al., 2011). Thus, site selection, 

regardless of purpose, must consider soilscape relationships. A soil 

profile description identifies the horizons and their thickness and 

provides context for data collection and interpretation. Soil property 

data by itself has little value without context; soil data requires 

an accompanying geo-referenced description. Sampling needs 

and strategies vary by project objectives. Various reviews and 

summaries (Buol et al., 2003; Soil Survey Staff, 2004; Soil Survey 

Staff, 2009; Robertson et al., 1999; Carter, 1993) outline sampling 

strategies and techniques.

Statistical design and analysis (e.g., random, randomized block, 

grid, transect, traverse, geostatistical) are important aspects 

of sample collection (Buol et al., 2003). Discussion of statistical 

methods and design is beyond the scope of this publication. 

Summary information is available in Webster and Oliver (2007) and 

Webster and Oliver (1990). Note, however, that statistical blocking 

by geomorphic context stratifies soil areas by similar geologic and 

pedogenic processes. Random sampling within a geomorphically 

stratified area allows determination of both random soil variation 

and systematic landscape variation (Hall and Olson, 1991).

SOILSCAPE SEQUENCES—Soil sampling commonly considers 

pedons as distinct points separate from adjoining soils. Soil water 

flow is generally interpreted as predominantly vertical; lateral flow 

receives considerably less emphasis. In many soilscapes, however, 

vertical flow is important but lateral flow is more influential. A slight 

difference in elevation (15 cm) in nearly level landscapes produces 

substantial hydrologic and morphological differences (Knuteson et 

al., 1989). Soilscape sampling and characterization is an important 

strategy for increasing and organizing both spatial and soil property 

data (Wysocki et al., 2011). This approach evaluates landscapescale processes that relate ecosystem dynamics to soil distribution.

TYPES OF SAMPLING

HORIZON SAMPLING—Cost and time limit the number of sample 

collections. The most effective and efficient strategy for sampling 
USDA-NRCS 8–2 September 2012

is by horizon. Soil horizons develop from natural processes 

acting over time. Variations in soil properties may occur within a 

horizon, but distinct differences generally occur between horizons. 

Consequently, soil horizons are a meaningful and comparable 

schema for sample collection (see graphic). Soil horizons vary in 

thickness and boundary (e.g., wavy, irregular, broken) within a 

pedon and across landscapes. Soil profile descriptions and horizon 

sampling techniques incorporate depth and boundary variability and 

can produce homogeneous samples. It is advisable to subsample 

soil horizons about 50 cm thick. Fixed-depth sampling alone 

does not capture such variation and may lead to the erroneous 

interpretation of data. 

INCREMENTAL SAMPLING—Project objectives (e.g., soil genesis 

or archeological) may require within-horizon detail. Property 

variation or trends within horizons require samples at specified 

increments (e.g., every 10 cm). Increment samples should be 

taken within horizons; sample depths should not cross horizon 

boundaries. Increment sampling provides more detail than horizon 

sampling but adds time and expense. This approach is generally 

limited to special projects.

FIXED-DEPTH SAMPLING—Specified objectives (e.g., surface 

compaction studies) may address properties by fixed depths (e.g., 

0-5 cm or 5-10 cm) instead of by soil horizons. This approach, while 

appropriate for certain purposes, precludes data comparison by 

horizon. Data collected by depth is comparable within a study and 

to other studies employing the same depths. Fixed-depth samples 

may straddle horizons that contain contrasting materials (e.g., 

sandy over clayey strata). The resultant data represents neither 

horizon and is difficult to interpret. Use this approach with caution.

Horizon

Horizon

Sampling

Incremental

Sampling

Fixed-Depth

Sampling

A

Bt

Btk

BC
USDA-NRCS 8–3 September 2012

SAMPLING TECHNIQUES

Excavate a fresh soil pit for sample collection. Avoid road cuts as 

sample sites because dust and exposure can alter soil properties. 

If excavation is not possible, collect samples from intact cores 

(e.g., Giddings tube). If an auger is the only means for sample 

collection, place the collected soil onto a tarp to identify and sample 

by horizon. For soil characterization, collect 3- to 4-kg samples. 

Soils with fragments up to 20 mm in size require a minimum 1 kg 

(dry weight) sample for a representative quantity (ASTM, 2004). If 

fragment size exceeds 20 mm, larger sample sizes are needed.

During sample collection:

1) Collect samples in a soil pit from the bottom up. This 

minimizes contamination by falling debris.

2) Collect the sample across a horizon’s full depth and breadth. 

Avoid atypical pockets or lenses, or subsample these 

separately.

SOIL SAMPLE KINDS

CHARACTERIZATION SAMPLES—Samples collected from a fully 

described soil chosen to be representative of a given soil series or 

soil landscape area. All horizons are bulk sampled to a depth of 200 

cm or more. In addition, three fist-sized clods are collected from 

each horizon for bulk density measurement. Bulk samples undergo 

a suite of analyses (e.g., particle size, 1500 kPa water content, CEC, 

pH, extractable cations, organic carbon, clay mineralogy, etc.).The 

specified analyses vary with soil composition. A Mollisol needs a 

different set of analyses for characterization than does an Andisol 

or Spodosol. Characterization sampling provides a complete set of 

measured values for soil comparison or extrapolation.

REFERENCE SAMPLES (grab samples)—Samples collected for 

a single or limited set of analyses (e.g., OC, PSA, pH) to answer 

a specific question. For example, there may be a question of 

whether or not the A horizon has sufficient organic carbon for mollic 

epipedon criteria (OC ≥ 0.6 %). References samples are generally 

targeted to specific horizons or layers (e.g., A horizon, Bt horizon, 

control section) in a profile. Sample intent is to answer a question 

quickly with little expense.
USDA-NRCS 8–4 September 2012

FIELD EQUIPMENT CHECKLIST

1. Digging Tools (commonly choose 1 or 2): see graphic

Bucket Auger

Sharp Shooter

Montana Sharp Shooter (for rocky soils)

Tile Spade (only for well cultivated or loose material)

Spade (standard shovel)

Push Probe (e.g., Backsaver®, Oakfield®)—include a

 clean-out tool

Pulaski

Soil Description

Knife

Hand Lens (10X or combination lenses)

Acid Bottle (1N HCl)

Water Bottle

Color Book (e.g., Munsell®, EarthColors®)

Picture Tapes (“pit tape”—metric preferred)

Tape Measure (metric or English and metric)

(3) Ultra-Fine Point Permanent Marker Pens

Pocket pH Kit or Electronic “Wand”

Pocket Soil Thermometer

Camera

Sample bags (for grab samples)

Soil Description Sheet (232 or PEDON description form)

Site Description

Field Note Book

GPS Unit

Abney Level

Clinometer

Compass

Altimeter (pocket-sized)

Field References

Field Book for Describing and Sampling Soils

Aerial Photographs

Topographic Maps (1:24,000, 7.5 min; 1:100,000)

Geology Maps

Soil Surveys (county or area)

AGI Field Sheets

Personal Protective Gear

Small First Aid Kit

Leather Gloves

Sunglasses

Insect Repellent

Sunscreen

Hat

Drinking water
USDA-NRCS 8–5 September 2012

EXAMPLES OF COMMON SOIL-SAMPLING EQUIPMENT

(Use of trade or company names is for informational purposes only 

and does not constitute an endorsement.)

Digging Tools/Shovel Types

Soil Probes Hydraulic Probes

Regular

pushtube

Tile probe

(solid

steel rod) 

Peat

sampler

(Macaulay) 

Giddings

tube

Bull

probe

Vibracore

Primary

use:

fine

earth 

locating

hard

contact 

organic

soils 

(not effective in

rocky materials) 

wet sands,

organics

(no co. frags)

Pulaski Standard

shovel 

Tile

spade

Sharpshooter

Montana

sharpshooter 

(all steel)

Primary

use: 

most

materials 

loose

material 

most

materials 

rocky

soil

vibrating

clamp Hinged

door 
USDA-NRCS 8–6 September 2012

REFERENCES

American Society for Testing and Materials (ASTM). 2004. Standard 

practice for description and identification of soils. D2488 Annual 

Book of ASTM Standards. Construction. Section 4, Soil and Rock; 

Dimension Stone. Vol. 04.08. Philadelphia, PA. 

Buol, S.W., R.J. Southard, R.C. Graham, and P.A. McDaniel. 2003. 

Soil genesis and classification. 5th edition. Iowa State Press, Ames, 

IA. ISBN: 0-8138-2873-2. 

Carter, M. (editor). 1993. Soil sampling and methods of analysis. 

Lewis Publishers, CRC Press, Inc., Boca Raton, FL. ISBN: 0-87371-

861-5.
USDA-NRCS 8–7 September 2012

Hall, G.F., and C.G. Olson. 1991. Predicting variability of soils from 

landscape models. In M.J. Mausbach and L.P. Wilding (eds.) Spatial 

variability of soils and landforms. Soil Sci. Soc. Am. Spec. Pub. #28, 

SSSA, Inc., Madison, WI. ISBN: 0-89118-198-7.

Knuteson, J.A., J.L. Richardson, D.D. Patterson, and L.D. Prunty. 

1989. Pedogenic carbonates in a Calciaquoll associated recharge 

wetland. Soil Sci. Soc. Am. J. 53:495-499.

Robertson, G.P., D.C. Coleman, C.S. Bledsoe, and P. Sollins 

(editors). 1999. Standard soil methods for long-term ecological 

research. Oxford University Press, Inc., New York, NY. ISBN: 0-19-

512083-3. 

Soil Survey Staff. 2004. Soil survey laboratory methods manual. 

Soil Survey Invest. Rep. (SSIR) 42, Version 4.0. R. Burt (ed.), 

USDA, Natural Resources Conservation Service. 

Soil Survey Staff. 2009. Soil survey field and laboratory methods 

manual. Soil Survey Invest. Rep. No. 51, Version 1.0. R. Burt (ed.), 

USDA, Natural Resources Conservation Service. Available at http://

soils.usda.gov/technical/.

Soil Survey Staff. 2012. National soil survey handbook (NSSH) 

[Online]. USDA, NRCS, National Soil Survey Center, Lincoln, NE 

(http://soils.usda.gov/technical/handbook/).

Webster R., and M.A. Oliver. 1990. Statistical methods in soil and 

land resource survey. Oxford University Press. Oxford, England. 

Webster R., and M.A. Oliver. 2007 Geostatistics for environmental 

scientists. 2nd edition. John Wiley and Sons, Inc. West Sussex, 

England. 

Wysocki, D.A., P.J. Schoeneberger, D.R. Hirmas, and H.E. LaGarry. 

2011. Geomorphology of soil landscapes. In P.M. Huang, Y. Li, and 

M.E. Sumner (eds.) Handbook of Soil Sciences: Properties and 

Processes, 2nd ed, pp. 29-1−29-26. CRC Press, Boca Raton, FL.

USDA-NRCS 9–1 September 2012

INDEX

A

Across Slope • 1–6, 3–40

Air Temperature • 1–1

Alpha Alpha Dipyridyl • 2–88

Location • 2–88

Anthric Saturation • 1–16

Anthropogenic Feature • 1–4, 3–1, 3–10, 3–20

Area Covered (%) Example • 7–1

Argillans • 2–32

Artifacts • 2–49

Cohesion • 2–51

Kind • 2–50

Penetrability • 2–51

Persistence • 2–51

Quantity • 2–50

Roundness • 2–50

Safety • 2–52

Shape • 2–51

Aspect • See Slope Aspect

B

Bathymetry • 2–97

Bedrock • 1–22

(Bedrock)-Fracture Interval Class • 1–24

Depth to Bedrock • 1–25

Kind • 1–22, 5–1

Weathering Class • 1–25

Biological Concentrations • 2–19, 2–22

Biological Crusts • 2–77, 2–79

Bottom Type • 2–100

Boundary Distinctness • 2–6 • See also Horizon Boundary 

Distinctness

Bridging (clay) • 2–32, 2–34

Brittleness • 2–65

Bulk Density Satiated

Discussion • 2–106

Bypass Flow • 2–75

C

Calcium Carbonate Equivalent Test • 2–88

Carbonate Stages • 2–30

Caret (The) (Horizon Nomenclature) • 2–5

Carpedolith • 2–80

Cementation Classes (Rupture Resistance) • 2–63
USDA-NRCS 9–2 September 2012

Cementing Agents • 2–64

Characterization Samples • 8–3

Chemical Agent • 2–87

Chemical Crusts • 2–78

Chemical Response • 2–85

Clay Depletions • 2–11, 2–12

Clay Films • 2–32

Climate • 1–1

Coastal Marine and Estuarine (Geomorphic Environments; 

Landforms) • 3–21

Coats • 2–32

Cohesion (Artifacts) • 2–51

Color Contrast • See Mottle Contrast

Color Location • 2–9

Color, Mechanical Condition • 2–9

Color Physical State (NASIS) • See Soil Matrix Color - Location or 

Condition

Color, Redoximorphic Condition • 2–9

Common Conversion Factors • 7–18

Common Soil Map Symbols (Traditional) • 7–22

Common Soil-Sampling Equipment (Examples) • 8–5

Comparison of Particle Size Classes in Different Systems (table) • 

2–45

Compositional Texture Modifiers • 2–41

Concentrations • 2–20

Boundary • 2–27

Color • 2–23

Contrast • 2–23

Hardness • 2–27

Kind • 2–20

Location • 2–26

Moisture State • 2–23

Quantity • 2–23

Shape • 2–25

Size • 2–23

Concentrations (Discussion) • 2–19

Concretions • 2–10, 2–12, 2–19, 2–20, 2–21

Consistence • 2–62

Contrast of Soil Mottles • 2–16, 2–18

Coordinates • 1–2, 2–98

Coprogenous Earth • 1–29, 2–41

Core Descriptions • 2–111

Core Settlement • 2–111

County FIPS Code • 1–3

Cracks • 2–75

Depth • 2–77

Kind • 2–76

Relative Frequency • 2–77

Crust-Related Cracks • 2–75, 2–76

Crusts • See Soil Crusts

Crystals • 2–19, 2–20, 2–21
USDA-NRCS 9–3 September 2012

D

Date • 1–1, 2–98

Decision Flowchart For Describing Soil Colors • 2–8

Delineation Size (Transect) • 1–3

Dendritic Tubular Pores • 2–73, 2–74

Densic Contact • 1–29

Densic Materials • 1–29

Depositional Crust • 2–78

Depressional (Landforms) • 3–35

Depth (To Bedrock) • 1–25

Describer(s) Name • 1–1, 2–98

Desert Pavement • 2–80

Diagnostic Characteristics - Mineral Soils • 1–29

Diagnostic Characteristics - Organic Soils • 1–29

Diagnostic Horizons • 1–28

Diagnostic Properties • 1–28

Diagnostic Subsurface Horizons • 1–28

Diatomaceous Earth • 1–29, 2–41

Dipyridyl • See Alpha Alpha Dipyridyl

Dissolved Oxygen • 2–102

Down Slope • 1–6, 3–40

Drainage • 1–11

Drainage Class • 1–11, 2–101

Drainage Network • See Drainage Pattern

Drainage Pattern • 3–1, 3–44

Durinode • 1–29, 2–21

Duripan • 1–28, 2–44

Duripan Fragments • 1–27, 2–46

E

Earth Cover - Kind • 1–16

Effervescence • 2–87

Chemical Agent • 2–87

Class • 2–87

Electrical Conductivity • 2–89

Electrical Conductivity of Subaqueous Soils • 2–106

Elevation • 1–5, 2–98, 3–39, 

Endosaturation • 1–15

English To Metric (conversions) • 7–17

Eolian Deposits • 1–18

Eolian (Geomorphic Environment; Landforms) • 3–26

Epipedons • 1–28

Episaturation • 1–16

Erosion • 1–25

Degree Class • 1–26

Kind • 1–25

Erosion Accelerated Kind • See Erosion Kind

Erosional Lag • 2–80
USDA-NRCS 9–4 September 2012

Erosional (Landforms) • 3–34

Estuarine (Geomorphic Environment; Landforms) • 3–21

Evaporites • 1–24, 5–3, 5–7

Excavation Difficulty • 2–69

Excavation Difficulty Class • 2–69

Extra-Structural Cracks • 2–75

F

Faunal Burrows • 2–80

Fecal Pellets • 2–22

Ferriargillans • 2–12, 2–32

Field Equipment Checklist • 8–4

Field Notes • 2–90

Field pH (NASIS) • See Reaction (pH)

Filaments • 2–25

Films • 2–12, 2–32

Final Core Length • 2–112

Finely Disseminated Materials • 2–19, 2–20, 2–21

FIPS Code • 1–3

Fissures • 2–75

Flat Plains (Geomorphic Components of) • 1–10, 3–43

Flooding • 1–13

Duration • 1–13

Frequency • 1–13

Months • 1–13

Fluidity • 2–65

Fluidity Class • 2–105

Fluvial (Geomorphic Environment; Landforms) • 3–24

Formation (Lithostratigraphic Unit) • 1–25, 5–12

Fragipan • 1–28

Fragment Hardness • See Rock and Other Fragments - Hardness

Fragment Roundness • See Rock and Other Fragments - Roundness

Fragments • See Rock and Other Fragments

Freeze-thaw Crust • 2–78

G

Geodetic Datum • 1–2, 2–98, 6–1

Geologic Formation (NASIS) • See Formation

Geologic Time Scale • See North American Geologic Time Scale

Geology • 5–1

References • 5–13

Geomorphic Component • 1–8, 3–41, 

Flat Plains • 1–10, 3–43, 3–2

Hills • 1–8, 3–42, 

Mountains • 1–9, 3–1, 3–43

Terraces, Stepped Landforms • 1–8, 3–42, 3–1

Geomorphic Description • 1–4, 3–1, 3–11

References • 3–46
USDA-NRCS 9–5 September 2012

Geomorphic Description (Outline) • 3–10

Geomorphic Description System • 3–1

Geomorphic Information • 1–4

Gilgai Microfeatures • 2–54

Glacial and Periglacial Deposits • 1–18

Glacial (Geomorphic Environment; Landforms) • 3–26

Glauconite • 2–19

GPS • 2–98

Ground Surface • 2–6

Group (Lithostratigraphic Unit) • 5–12

Guide To Map Scales And Minimum-Size Delineations • 7–21

Gully (Erosion) • 1–25

Gully (microfeature) • 3–18, 3–25, 3–34

H

Hard Rock Fragments • See Rock Fragments

Hierarchical Rank of Lithostratigraphic Units • 5–12

Hills (Geomorphic Components of) • 1–8, 3–42

Hillslope Position • See Hillslope - Profile Position

Hillslope - Profile Position • 1–7, 3–1, 3–41

Horizon and Layer Designations • 2–2

Horizon Boundary • 2–6, 2–104

Distinctness • 2–6, 2–104

Topography • 2–7

Horizon Depth • 2–6

Horizon Feature Kind (NASIS) • See Special Features

Horizon & Layer Designations • 2–103, 4–1

Horizon & Layer Designations Conversion Charts • 4–6

Horizon Modifiers (Other) • 2–5

Caret • 2–5

Numerical Prefixes • 2–5

Prime • 2–5

Horizon Subscripts • See Horizon Suffixes

Horizon Suffixes • 2–4, 2–103, 4–3, 4–8

Horizon Suffixes for Subaqueous Soils (Discussion) • 2–103

Horizon Thickness • 2–6

Human Artifacts • See Artifacts

Hydrothermal • 3–30 • See also Volcanic and Hydrothermal 

(Geomorphic Environments; Landforms)

Hypocoats • 2–12, 2–32, 2–34

I

Ice Wedge Cast • 2–80

Igneous Rocks • 1–22, 5–1

Igneous Rocks Chart • 5–5

In-Place Deposits • 1–19

Insect Casts • 2–19, 2–20, 2–22

Inside Length • 2–111
USDA-NRCS 9–6 September 2012

Interbedded Rocks • 1–24, 5–3

Interstitial Pores • 2–74

Inter-Structural Voids • 2–73

Interval (Transect) • 1–4

Iron Depletions • 2–10

Irregular Pores • 2–73, 2–74

K

Krotovinas • 2–80

Ksat • See also Saturated Hydraulic Conductivity

Ksat Class Estimate • 7–10

L

Lacustrine (Geomorphic Environment; Landforms) • 3–23

Lamellae • 1–29, 2–25, 2–80

Lamina • 2–80

Land Cover • 1–16

Kind • 1–16

Landform • 1–4, 3–1, 3–10, 3–12

Landscape • 1–4, 3–1, 3–10, 3–11

Landslide • See Mass Movement (Geomorphic Environment; 

Landforms), Mass Movement Types for Soil Survey

Landuse • See Earth Cover - Kind

Limnic Materials • 1–29, 2–41

Lithic Contact • 1–29

Lithologic Discontinuities

Discussion • 2–103

Lithostratigraphic Units • 1–25, 5–12

Local Physiographic / Geographic Name • 1–4, 3–1, 3–9

Location • 1–2, 6–1

Description • 2–100

References • 6–7

Loess Doll (Kindchen, Puppy) • 2–22

M

Major Land Resource Area • 1–3

Manganese Effervescence Agent • See Effervescence Agent

Manganese Effervescence Class • See Effervescence Class

Mangans • 2–12, 2–32

Manner of Failure • 2–65

Map Unit • 2–100

Marl • 1–29, 2–41

Masses • 2–10, 2–12, 2–19, 2–20, 2–21

Mass Movement Deposits • 1–19

Mass Movement (Geomorphic Environment; Landforms) • 3–29

Mass Movement Types for Soil Survey • 5–8
USDA-NRCS 9–7 September 2012

Master Horizons • 2–2, 4–1, 4–6

Matrix Color • See Soil Matrix Color

Mean Sea Level • 1–5, 3–39

Measurement Equivalents & Conversions • 7–16

Member (Lithostratigraphic Unit) • 5–12

Metamorphic Rocks • 1–23, 5–2

Metamorphic Rocks chart • 5–6

Metric To English (conversions) • 7–16

Microbiotic Crust • 2–77

Microfeature • 1–4, 3–1, 3–10, 3–18

Microfeature (terms) • 3–18

Microrelief • 1–10, 2–54, 3–1, 3–44

Mineral Crusts • 2–78

Minimum Data Set • 2–90

Miscellaneous • 7–1

Miscellaneous Field Notes • 2–90

MLRA • 1–3

Month / Day / Year • 1–1

Mottles • 2–18

Color • 2–18

Contrast (also called Color Contrast) • 2–18

Moisture State • 2–18

Quantity • 2–18

Shape • 2–18

Size • 2–18

Mountains (Geomorphic Components of) • 3–43

Multicolored Pattern • 2–9

N

Name • 1–1

Nodules • 2–10, 2–12, 2–19, 2–20, 2–21

North American Geologic Time Scale • 5–9

O

Observation Method • 2–1, 2–101

Kind • 2–1, 2–101

Relative Size • 2–2

Observed Soil Moisture Status (NASIS) • 1–14 • See also (Soil) 

Water State

Odor • 2–90, 2–106

Intensity • 2–90, 2–106

Kind • 2–90, 2–106

Organic Deposits • 1–20

Organics • 1–24, 5–3

Ortstein • 1–28, 2–44

Ortstein Fragments • 1–27, 2–46

Oxidation / Reduction • 2–10
USDA-NRCS 9–8 September 2012

P

Paralithic Contact • 1–29

Paralithic Materials • 1–29

Pararock Fragments • 2–39

Parent Material • 1–18

Particle Size Classes • 2–45

Ped and Void Surface Features • 2–32

Amount • 2–35

Color • 2–36

Continuity • 2–35

Distinctness • 2–35

Kind • 2–32

Location • 2–36

Pedogenic Carbonate Development Stages

Coarse Fragment Matrix • 2–31

Fine Earth Matrix • 2–30

Pedogenic Carbonate Stages (Discussion) • 2–28

Pedon Description

Example • 2–95

Form • 2–93

Pendant • 2–27

Penetrability (Artifacts) • 2–51

Penetration Orientation • 2–68

Penetration Resistance • 2–67

Penetration Resistance Class • 2–68

Periglacial (Geomorphic Environment; Landforms) • 3–28

Permeability Classes • 2–85

Permeability (Discussion) • 2–81

Peroxide Color Change • 2–104

Persistence (Artifacts) • 2–51

Petrocalcic Horizon • 1–28, 2–44

Petroferric • 1–29, 2–44

Petrogypsic Horizon • 1–28, 2–44

pH • 2–85, 2–102

Method • 2–86, 2–102

Physical Crusts • 2–78

Physiographic Division • 1–4, 3–1, 3–2

Physiographic Location • 1–4, 3–1, 3–2

Physiographic Province • 1–4, 3–1, 3–2

Physiographic Section • 1–4, 3–1, 3–2

Phytoliths (plant) • 2–22

Pipestems • 2–25

Piping (Erosion) • 1–25

Placic Horizon • 1–28

Plant Common Name • 1–18

Plant Opal • See Phytoliths

Plant Scientific Name • 1–18

Plant Symbol • 1–17

Plasticity • 2–66

Plasticity Class • 2–66
USDA-NRCS 9–9 September 2012

Plinthite • 1–29, 2–25

Pocket Penetrometer • 2–67

Ponding • 1–14

Depth • 1–14

Duration • 1–14

Frequency • 1–14

Pores • 2–73

Quantity • 2–70

Quantity Class • 2–70

Shape • 2–73, 2–74

Size • 2–70

Size Classes • 2–70, 2–72

Vertical Continuity • 2–75

Pores (Discussion) • 2–73

Precipitates • 1–24, 5–3, 5–7

Preferential Flow • 2–75

Pressure Faces • 2–32, 2–34

Primary Packing Voids • 2–74

Prime (The) (Horizon Nomenclature) • 2–5, 2–104

Profile / Pedon Description • 2–1

References • 2–115

Public Land Survey • 6–2

Pyroclastic Terms • 5–11

Q

quadrangle • 1–2

R

Raindrop Impact Crust • 2–78

Range (location) • 6–3

Reaction Oxidized pH • 2–105

Discussion • 2–105

Reaction (pH) • 2–85

Reaction to Alpha-dipyridl (NASIS) • See Reduced Conditions

Reaction to H2O2 (Peroxide Color Change) • 2–104

Redox Concentrations • 2–10, 2–12

Redox Depletions • 2–10, 2–12

Redoximorphic Features • 2–12

Boundary • 2–17

Color • 2–17

Contrast • 2–15

Hardness • 2–17

Kind • 2–12

Location • 2–17

Moisture State • 2–17

Quantity • 2–13

Shape • 2–17

Size • 2–13
USDA-NRCS 9–10 September 2012

Redoximorphic Features-RMF (Discussion) • 2–10

Reduced Conditions • 2–88

Reduced Matrix • 2–11, 2–12

Reduced Monosulfide Presence • 2–104

Reference Samples • 8–3

Relative_Exposure_UOM • 2–2

Relative Size (of Exposure) • 2–2

Relative Slope Segment Position • 1–6, 3–39

Restriction • 1–30

Kind • 1–30

Rill (Erosion) • 1–25

Rill (Microfeature) • 3–18, 3–33, 3–34

Riser Length • 2–111

RMF Shapes • 2–26

Rock and Other Fragments • 2–46

Hardness • 2–49

Kind • 2–46

Roundness • 2–48

Size Classes and Descriptive Terms • 2–47

Volume Percent • 2–47

Rock Charts • 5–4

Rock Fragments • 2–38, 2–43, 2–46

Quantity • 2–38

Size • 2–38

Root Channels • 2–73

Root Pseudomorphs • 2–25

Roots • 2–70

Location • 2–72

Quantity • 2–70

Quantity Class • 2–70

Size • 2–70

Size Classes • 2–70, 2–72

Roundness (Artifacts) • 2–50

Roundness (Rock and Other Fragments) • 2–48, 2–49

Rupture Resistance • 2–62

Blocks, Peds, And Clods • 2–63

Surface Crusts and Plates • 2–64

S

Safety (Artifacts) • 2–52

Salinity • 2–88, 2–102, 2–106

Salinity Class • 2–89

Sampling Techniques • 8–3

Sampling, Types of • 8–1

Fixed-Depth Sampling • 8–2

Horizon Sampling • 8–1

Incremental Sampling • 8–2

Sand Coats • 2–32

Satiation • 1–15
USDA-NRCS 9–11 September 2012

Saturated Hydraulic Conductivity • 2–83

Saturated Hydraulic Conductivity Classes • 2–84

Saturated Hydraulic Conductivity (Discussion) • 2–81

Saturation • 1–15

Scale (topographic quadrangle) • 1–2

Scientific Plant Name • 1–18

Secondary Carbonates • 1–30

Section (location) • 6–3

Sedimentary and Volcaniclastic Rocks Chart • 5–7

Sedimentary Rocks • 1–23, 5–2

Series Name • 1–4

Shape (Artifacts) • 2–51

Sheet (Erosion) • 1–25

Shell Fragments • 2–22

Shot • 2–25

Silt Coats • 2–32

Site Description • 1–1, 2–98, 2–111

Site/Pedon ID • 2–98

Skeletans • 2–32

Slake Test • 2–40

Slickensides • 1–29, 2–33

Slope Aspect • 1–5, 3–39, 

Slope Complexity • 1–5, 3–39, 

Slope Gradient • 1–5, 3–39, 

Slope (Landforms) • 3–32

Slope Shape • 1–6, 3–40, 

Smeariness • 2–65

Sodium Adsorption Ratio (SAR) • 2–89

Soft, Powdery Lime • See Secondary Carbonates

Soft Rock Fragments • See Pararock Fragments

Soil Color • 2–8

Soil Crusts • 2–79

Kind • 2–79

Soil Crusts (Discussion) • 2–77

Soil Drainage Class • See Drainage Class

Soil Matrix Color • 2–9

Soil Matrix Color - Location or Condition • 2–9

Soil Moisture Regimes • 4–11

Soil Moisture Status • See Soil Water State

Soil Permeability • 2–81

Soil Sample Kinds • 8–3

Soil Sampling • 8–1

References • 8–6

Soilscape Sequences • 8–1

Soil Series Name • 1–4

Soil Structure • 2–52

Grade • 2–55

Size • 2–55

Type • 2–52

Soil Surface • 2–6

Soil Survey Area Identification Number (SSID) • 1–2
USDA-NRCS 9–12 September 2012

Soil Taxonomy • 4–1

References • 4–14

Soil Taxonomy Classification • 1–30

Soil Temperature • 1–1

Soil Temperature Depth • 1–1

Soil Temperature Regimes and Classes • 4–13

Soil Textural Triangle • See Textural Triangle

Soil Texture • 2–36

Soil Water Repellency • 7–15

Soil Water Repellency (Discussion) • 7–14

Solution (Geomorphic Environment; Landforms) • 3–25

Special Features • 2–80

Sphericity • 2–48

Sponge Spicules • 2–22

State Physiographic Area • 1–4, 3–1, 3–9

State Plane Coordinate System • 6–7

Stickiness • 2–66

Stickiness Class • 2–66

Stone Line • 2–80

Stop Number (Transect) • 1–4

Stress Features • 2–32, 2–34

Stringers • 2–25

Structure • See Soil Structure

Structure Shape • See Soil Structure - Type

Subaqueous Soils • 2–97

Subaqueous Soils Profile Description

Example • 2–110

Form • 2–109

Submerged Aquatic Vegetation • 2–101

Subordinate Distinctions • See Horizon Suffixes

Sulfides

Discussion • 2–106

Surface Coats • 2–12

Surface Crust and Plates Classes (Rupture Resistance) • 2–64

Surface Crust and Plates (Rupture Resistance) • 2–62

Surface Crusts • 2–77 • See also Soil Crusts

Surface Fragments • 1–26

Class • 1–26

Kind • 1–26

Mean Distance Between Fragments • 1–26

Shape • 1–26

Size • 1–26

Surface Morphometry • 1–5, 3–39, 

T

Table Comparing Particle Size Systems • 2–45

Tabular List for Determination of Color Contrast • 2–16

Tectonic and Structural (Geomorphic Environments; Landforms) • 

3–31
USDA-NRCS 9–13 September 2012

Terms Used In Lieu of Texture • 2–43

Terraces and Stepped Landforms (Geomorphic Components of) • 

1–8

Terraces, Stepped Landforms (Geomorphic Components of) • 3–42

Textural Triangle

Combined Textural Triangles: Fine Earth Texture Classes and 

Family Particle-Size Classes • 4–11

Family Particle-Size Classes • 4–10

Fine Earth Texture Classes • 2–38

Texture Class • 2–37

Texture Modifiers • 2–38, 2–39

Texture Modifiers (Compositional) • 2–41

Threadlike • 2–25

Tidal Datum (Discussion) • 2–99

Tidal Period • 2–111

Till Terms • 5–10

Time

End • 2–98

Start • 2–98

Time Scale • See North American Geologic Time Scale

Tongues • 2–80

Topographic Quadrangle • 1–2

Total Pipe Length • 2–111

Townships (location) • 6–3

Transects • 1–3

Delineation Size • 1–3

ID • 1–4

Kind • 1–3

Trans-Horizon Cracks • 2–75, 2–76

Transitional Horizons • 2–2, 4–1

Transported Deposits • 1–21

Tubular Pores • 2–73, 2–74

Tunnel (Erosion) • 1–25

U

Unconfined Compressive Strength • 2–67

Undulation • 2–6

Universal Transverse Mercator (UTM) Rectangular Coordinate 

System • 6–5

V

Variegated (color) • 2–9

Vegetation • 1–17

Vegetation Cover • 1–18

Vertical Datum

Discussion • 2–100

Vesicular Crust • 2–78
USDA-NRCS 9–14 September 2012

Vesicular Pores • 2–74

Vibracore Log Sheet

Example • 2–114

Form • 2–113

Vibracore Sampling for Subaqueous Soils (Discussion) • 2–111

Volcanic and Hydrothermal (Geomorphic Environment; Landforms) 

• 3–30

Volcanic Deposits • 1–20

Volcaniclastic Rock Terms • 5–7

Vughs • 2–73, 2–74

W

Water Bodies (Landforms) • 3–37

Water Column Measurements • 2–102

Water Depth • 2–100, 2–111

Water Laid Deposits • 1–21

Water Repellent Layer • 2–80

Water Status • 1–11

Water Table • See Depth to Water Table, Seasonal High Water Table

Water Temperature • 2–102

Waypoint • 2–98

Wedge Structure • 2–53, 2–54

Wetland (Landforms) • 3–36

Where Core Is Stored • 2–112

0 1 2 3 4 5 6

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Inches Centimeters