Natural Resources Conservation Service

Soils

United States Department of Agriculture

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Technical References

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Policy and Procedure

Technical Soil Services Handbook - operational and procedural policy and guidance for technical soil services within NRCS.

National Soil Survey Handbook - policy, definitions, and procedures for conducting soil survey.

Soil Survey Manual - major principles and practices for soil surveys.
— Updates to the Soil Survey Manual

Soil Change Guide - Procedures for Soil Survey and Resource Inventory - designed for soil survey, vegetation, and ecological site or unit inventory work in order to help soil scientists and other inventory specialists collect interpretable data about soil change.

National Ecological Site Handbook - standards, guidelines, definitions, policies, responsibilities, and procedures for conducting the collaborative process of ecological site description (ESD) development.

Land-Capability Classification (Ag Handbook 210; 1961) (PDF; 782 KB) - Since soil surveys are based on all of the characteristics of soils that influence their use and management, interpretations are needed for each of the many uses. Among these interpretations the Land Capability Classification is one of the most important. It groups soils into capability units, subclasses, and classes. This grouping serves as an introduction of the soil map to farmers, other land users, land use planners, people in agribusiness, elected officials and others. The grouping explains the limitations and hazards for a specific agricultural use.

Technical Notes - specific technical subjects for soil scientists.

National Instructions - specific project guidance to offices involved.

Classification

Soil Taxonomy - principal reference to soil classification.

Keys to Soil Taxonomy - taxonomic keys for field classification.

Soil Geography

Land Resource Regions and Major Land Resource Areas of the United States, the Caribbean, and the Pacific Basin (Ag Handbook 296) - This publication describes 28 land resource regions and the physiography, geology, climate, water resources, soils, biological resources, and kinds of land use in 278 major land resource areas in the United States, the Caribbean, and the Pacific Basin.

Field Guides

Field Book for Describing and Sampling Soils - standards for observing and recording soil and site characteristics.

Field Guide to Classify Biological Soil Crusts for Ecological Site Evaluation (PDF; 1.66 MB)

This field guide was written by Dr. Nicole Pietrasiak, now with John Carroll University. Biological soil crusts (also known as microbiotic, cryptobiotic, cryptogamic, microphytic soil crusts, or, for short, biocrusts) are crucial components of terrestrial ecosystems. It provides a dichotomous key with details, explanations, and illustrations for biocrust community types. It is best aligned with conditions in areas such as the California Coastal Plain, Southern California Mountains, Sierra Nevada Mountains, Southern Nevada Basin and Range, Mojave Desert, and the Lower Colorado Desert.

Dr. Peitrasiak’s work was supported by the NRCS and is being posted for field use and professional evaluation. Please send any comments to the National Leader for Soil Survey Standards, currently David.Hoover@lin.usda.gov.

Field Indicators of Hydric Soils, version 7.0 (PDF; 5.3 MB)

Errata (March 2013) (DOC; 22 KB)
A Guide to Hydric Soils in the Mid-Atlantic Region, version 2.0 (PDF; 6.04 MB)

Soil Survey Office Laboratory References

Soil Survey Field and Laboratory Methods Manual (SSIR 51), version 2.0 (1-31-14; PDF; 10.3 MB)

Particle-size analysis by hydrometer data entry forms (1-31-11; XLS; 386 KB)

Soil Survey Field and Laboratory Methods Manual (SSIR 51), version 1.0, obsolete. (11-2-09; PDF; 8.8 MB)

Addenda to Version 1.0
- 3.3 Bulk Density (4-7-11; PDF; 114 KB)
- 4.6 Electrical Conductivity and Soluble Salts (4-7-11; PDF; 169 KB)

Soil Survey Office Laboratory Safety Guide, version 2.0 (8-29-16; PDF; 229 KB)

Material Safety Data Sheets (MSDS) and recommended chemical disposal procedure (10-23-09; PDF; 3.2 MB)

Laboratory Methods and Information

Lab Methods Manual (SSIR 42) - soil laboratory methodology and reference for the laboratory analyst.

Soil Survey Laboratory Information Manual (SSIR 45) - Companion reference to the Laboratory Methods Manual, SSIR No. 42. Sampling methodology, descriptions of KSSL data sheets, and other information to help users of lab data.

Testing Methods for Phosphorus and Organic Matter

Soil Sample Submission Protocol for the KSSL (11-29-16; PDF; 1.61 MB) - Documentation and worksheets (below) necessary for KSSL sample submission.

Soil Sample Submission Worksheets (6-17-15; ZIP; 292 KB)

Geomorphic Description System

These documents provide a descriptive method and a technical guide for applying and understanding geomorphic and geologic concepts and terms for soil inventory in the USA National Cooperative Soil Survey (NCSS) Program.

Geomorphic Description System, version 4.2 (PDF; 2.5 MB)

Glossary of Landform and Geologic Terms (Part 629 of the National Soil Survey Handbook) (DOC; 1.1 MB)

Geophysical Investigations

Dr. Jim Doolittle, retired soil scientist, produced many trip reports on ground-penetrating radar (GPR) and electromagnetic induction (EMI). These trip reports document the development of both GPR and EMI and associated technologies in soil surveys, soil investigations, and archaeological and engineering projects. A majority of the reports have been scanned in and sorted by Activity (GPR or EMI), Fiscal Year (1983 to 2015), International, and States.

Trip Reports

Installing Monitoring Wells in Soils

This document provides general guidance on how to install and use piezometers and water-table wells to investigate soil water regimes under conditions commonly encountered in Soil Survey and hydropedology studies.

Installing Monitoring Wells in Soils, version 1.0 (PDF; 1.9 MB)

The file below is a bibliography of publications from Wet Soils Monitoring Projects across the United States.

Bibliography (PDF; 70 KB)

Forms

Excel Pedon Description Forms

Excel Ecological Site Inventory (ESI) Forms

National Soil Information System (NASIS)

NASIS Tools

NASIS Metadata

Land Use (Title 310)

National Land Evaluation and Site Assessment (LESA) Handbook (PDF; 11.0 MB) – This handbook explains the preparation and use of the LESA system. It was developed to meet the requirements of the Farmland Protection Policy Act. The Land Evaluation (LE) part of LESA is combined with the site assessment (SA) part of LESA to determine the total value for a specific site for agriculture. The higher the total value of LESA, the higher the capabilities of that site for agricultural. The LESA system can help units of government meet the following two overall objectives: (1) facilitate identification and protection of important agricultural land, and (2) assist in implementing farmland protection policies. LESA utilizes soil survey information and interpretations, and planning concepts and principles. It can be used to facilitate decision making by State and local planners, landholders, developers, and governing officials.

Land Evaluation (LE) part of LESA (PDF; 802 KB)
Site Assessment (SA) part of LESA (PDF; 1.18 MB)

Red Tart Cherry Site Inventory for Grand Traverse County, Michigan (PDF; 9.63 MB) – This document explains how the local Land Evaluation (LE) committee established the soil, topography, and climate requirements to designate Unique Farmland and the LE numerical values for local Land Evaluation and Site Assessment (LESA). It includes discussion of facilities to process the cherries for market. The 7CFR657.5(b) defines the prerequisites for designating soil map units as unique farmland.