NSSH Amendment 23

February 2013

This is a summary of changes to the National Soil Survey Handbook (NSSH). The official copy of the NSSH is in HTML format and MSWord files at

Part 618 – Soil Properties and Qualities

  1. Corrected abbreviation for the MLRA soil survey office in Subpart A, section 618.1
  2. Updated 2 occurrences of “Soil Survey Laboratory” to “NSSC Kellogg Soil Survey Laboratory.”
  3. Added new section named “Artifacts in the Soil” (Subpart A, section 618.5) to provide guidance on populating data for anthropogenic soils. Renumbered all subsequent sections in Subpart A.
  4. Added new section named “Bulk Density, Satiated” (Subpart A, section 618.9) to provide guidance on populating data for subaqueous soils.
  5. Added sentences to the “significance” items of the following properties and qualities explaining their use in soil classification:
    • Bulk Density One-Third Bar
    • Calcium Carbonate Equivalent
    • Cation-Exchange Capacity NH4OAc pH 7
    • Electrical Conductivity
    • Electrical Conductivity 1:5 (volume)
    • Exchangeable Sodium
    • Extractable Acidity
    • Extractable Aluminum
    • Fragments in the Soil
    • Gypsum
    • Linear Extensibility Percent
    • Reaction, Soil (pH)
    • Saturated Hydraulic Conductivity
    • Sodium Adsorption Ratio
    • Slope Gradient
    • Sum of Bases
    • Texture Class, Texture Modifier, and Terms Used in Lieu of Texture
  6. Modified identical statements in the sections named “Diagnostic Horizon Feature - Depth to Bottom," “Diagnostic Horizon Feature - Depth to Top," “Horizon Depth to Bottom,” and “Horizon Depth to Top,” to reconcile the NSSH with the Soil Survey Manual on what the top of the soil is when surface cover of fragments is 80 percent or more.
  7. Revised the “Effective Cation-Exchange Capacity” section (now Subpart A, section 618.19) to correct errors and omissions in the guidance.
  8. Added sentences to the “Entries” items of several soil properties (Electrical Conductivity, Linear Extensibility Percent, and Reaction, Soil (pH)) to clarify that high and low values do not need to correspond with class limits if more precise data is available.
  9. Added new section named “Electrical Conductivity 1:5 (volume)” (Subpart A, section 618.21) to provide guidance on populating data for subaqueous soils.
  10. Added new section named “Exchangeable Sodium” (Subpart A, section 618.27) to provide guidance on populating this new data element in NASIS.
  11. Revised the “Entries” item for the “Flooding Frequency Class, Duration Class, and Month” section (now Subpart A, section 618.30) to clarify the guidance on data population.
  12. Added some clarification and a new reference to the “Fragments in the Soil” section (now Subpart A, section 618.31) to clarify differences between fragments and artifacts.
  13. Revised guidance on entries when populating the depths of combination horizons in the “Horizon Designation” section (now Subpart A, section 618.37).
  14. Revised the “Reaction, Soil (pH) section (now Subpart A, section 618.51) to add discussion on oxidized pH by the hydrogen peroxide test, delta pH method. Added a reference document (SSIR 51) as a third item in the measurement portion of the section.
  15. Revised the “Slope Aspect” section (now Subpart A, section 618.54) with changes proposed by the SDJR technical team.
  16. Corrected several abbreviations in the “Soil Erodibility Factors for WEPP” section (now Subpart A, section 618.59).
  17. Revised the “Soil Temperature” section (now Subpart A, section 618.62) to accommodate the new data element on mean annual soil temperature in the NASIS Component table. Revised, reorganized, and clarified all statements pertaining to mean monthly soil temperature data.
  18. Modified the paragraph in the “Texture Class, Texture Modifier, and Terms Used in Lieu of Texture” section (now Subpart A, section 618.71 E.) allowing multiple textures for surface horizons. Also expanded text on the sentence which specifies the need for setting the RV indicator. Updated text to specify that the term used in lieu of texture “material” is only appropriate to use with the texture modifier “cemented” reflecting current usage. Numerous revisions were made to item H “Texture Modifier” to clarity and better organize the guidance as well adding new application rules for horizons containing combinations of artifacts and fragments.
  19. Added new section named “Water Temperature” (Subpart A, section 618.76) to provide guidance on populating this new data element in NASIS.
  20. Added one correction and some suggested additions for Subpart B, Exhibits, Section 618.84 Potential Frost Action.