NRCS Hydric Soils Database Selection Criteria Update

Content

ACTION:

Notice of changes to the National Soil Information System (NASIS) Database Selection Criteria for Hydric Soils of the United
States.

SUMMARY:

The National Technical Committee for Hydric Soils (NTCHS) has updated the hydric criteria used to select map unit components
for the hydric soils list. The former database selection criteria created to select soils that may meet the definition of
hydric soils did not include subaqueous soils. As required by 7 CFR 12.31, NRCS is hereby providing notice of the changes
to the selection criteria for hydric soils as set forth in the NTCHS publication “Hydric Soils of the United States,” Miscellaneous
Publication 1491, U.S. Department of Agriculture, Soil Conservation Service, June 1991 (see also 60 FR 10349). These changes
will add soil components that represent subaqueous landforms to the list of hydric soils and reflect refinements in knowledge
of the soils of the United States as subaqueous soils are now mapped in previously unmapped areas. These soils have always
met the hydric definition, whether identified by the criteria or not, and thus represent an insignificant change in acreage
of hydric soils.

DATES:

Comments must be received on or before April 24, 2026.

ADDRESSES:

We invite you to submit comments in response to this notice. You may submit your comments through one of the following methods
below:

• Federal eRulemaking Portal: Go to https://www.regulations.gov and search

     for Docket ID NRCS-2026-0001. Follow the online instructions for submitting comments; or

• Mail: Cory Owens, National Resource Soil Scientist; active Chairperson for NTCHS, Soil and Plant Science Division, NRCS, USDA, 1201
NE Lloyd Blvd. Ste. 900, Portland, OR 97232. In your comment, please specify the Docket ID NRCS-2026-0001.

All comments received will be made publicly available on https://www.regulations.gov.

FOR FURTHER INFORMATION CONTACT:

Cory Owens, National Resource Soil Scientist; active Chairperson for NTCHS, Soil and Plant Science Division, NRCS, USDA, 1201
NE Lloyd Blvd. Ste. 900, Portland, OR 97232; telephone: (503) 414-3261; email: cory.owens@usda.gov. Individuals who require alternative means for communication should contact the USDA TARGET Center at (202) 720-2600 (voice
and text telephone (TTY)) or dial 711 for Telecommunications Relay Service (both voice and text telephone users can initiate
this call from any telephone).

SUPPLEMENTARY INFORMATION:

NRCS is responsible for developing database selection criteria, maintaining official lists, and implementing procedures to
identify and list hydric soils under the Food Security Act. These criteria and approved lists of potentially hydric soil map
unit components are developed in consultation with the NTCHS and made available to the public on the NTCHS national web page: https://www.nrcs.usda.gov/conservation-basics/natural-resource-concerns/soil/national-technical-committee-for-hydric-soils#criteria. The lists of hydric soils are created by using National Soil Information System (NASIS) database selection criteria. These
criteria are selected soil properties documented in “Soil Taxonomy” (Soil Survey Staff, 1999). The NTCHS has updated the criteria
to include the taxonomic subgroup Wassents to accurately represent newly mapped subaqueous soils.

Hydric soil lists have a number of agricultural and nonagricultural applications. These include assistance in land-use planning,
conservation planning, and assessment of potential wildlife habitat. These activities potentially interface with wetland functions
and the environmental services they provide, including potential direct benefits to both urban and rural populations and wildlife
habitat. Hydric soils lists play a critical role in environmental planning and wetland identification.

The changes to the criteria were thoroughly discussed and approved by the NTCHS at the annual business meeting in May 2024
in Charlotte, North Carolina. This decision was part of formal deliberations recorded in the meeting minutes as posted on
the NRCS Hydric Soils web page, found at https://www.nrcs.usda.gov/conservation-basics/natural-resource-concerns/soil/hydric-soils. The changes have also been addressed and acknowledged at several of the Hydric Soils Committee meetings during the 2024 Regional
Conferences of the National Cooperative Soil Survey held in respective regions of the United States. As shown below, criteria
1 is updated to include the subgroup of Wassents.

The updated criteria, with changes underlined, are as follows:

(1) All Histels except Folistels, all Histosols except Folists, and all Wassents; or

(2) Map unit components in Aquic suborders, great groups, or subgroups, Albolls suborder, Historthels great group, Histoturbels
great group, or Andic, Cumulic, Pachic, or Vitrandic subgroups that:

(a) Based on the range of characteristics for the soil series, will at least in part meet one or more field indicators of
hydric soils in the United States, or

(b) Show evidence that the soil meets the definition of a hydric soil;

(3) Map unit components that are frequently ponded for long duration or very long duration during the growing season that:

(a) Based on the range of characteristics for the soil series, will at least in part meet one or more field indicators of
hydric soils in the United States, or

(b) Show evidence that the soil meets the definition of a hydric soil; or

(4) Map unit components that are frequently flooded for long duration or very long duration during the growing season that:

(a) Based on the range of characteristics for the soil series, will at least in part meet one or more field indicators of
hydric soils in the United States, or

(b) Show evidence that the soils meet the definition of a hydric soil.

Glossary of Terms Used in Hydric Soils Criteria

Anaerobic means a situation in which molecular oxygen is virtually absent from the environment.

Artificial hydric soil means a soil that meets the definition of a hydric soil as a result of an artificially induced hydrologic regime and did not
meet the definition before the artificial measures were applied.

Drained means a condition in which ground or surface water has been removed by artificial means.

Flooded means a condition in which the soil surface is temporarily covered with flowing water from any source, such as streams overflowing
their banks, runoff from adjacent or surrounding slopes, inflow from high tides, or any combination of sources.

Frequently flooded, ponded, saturated is a frequency class in which flooding, ponding, or saturation is likely to occur often under usual weather conditions (more
than 50 percent chance in any year, or more than 50 times in 100 years).

Hydric soil means a soil that formed under conditions of saturation, flooding, or ponding long enough during the growing season to develop
anaerobic conditions in the upper part. This definition includes soils that developed under anaerobic conditions in the upper
part but no longer experience these conditions due to hydrologic alteration such as those hydric soils that have been artificially
drained or protected (e.g., ditches or levees).

Long duration means a duration class in which inundation for a single event ranges from 7 days to 1 month.

Map unit means a collection of areas defined and named the same in terms of their soil components or miscellaneous areas or both.

Map unit components means the collection of soils and miscellaneous areas found within a map unit.

Phase, map unit means a subdivision of a map unit based on features that affect its use and management (e.g., slope, surface texture, stoniness, and thickness).

Ponded means a condition in which water stands in a closed depression. The water is removed only by percolation, evaporation, or
transpiration.

Very long duration means a duration class in which inundation for a single event is greater than 1 month.

What's included on the hydric soils lists?

“Hydric Soils of the United States” is a compilation of all map units with either a major or minor component that is at least
in part hydric. This could include components that are soil series, components that are classified at categories higher than
the series level in Soil Taxonomy, and miscellaneous land types. Because the list includes both major and minor (small) percentages
for map units, in some cases most of the map unit may not be hydric. Also, some components may be phases of soil series

  that have a range of characteristics that both meet and do not meet hydric indicator requirements; therefore, only a portion
  of that component's concept (or range in characteristics) may in fact be hydric. The list is useful in identifying map units
  that may contain hydric soils.

The NRCS Hydric Soil List is available as a full national list or by state using the State Soil Data Access Hydric Soil List
web report: https://www.nrcs.usda.gov/publications/query-by-state.html; or by soil survey area using the Soil Data Access Hydric Soils List web report: https://www.nrcs.usda.gov/publications/query-by-ssa.html.

Colton Buckley, Associate Chief, Natural Resources Conservation Service. [FR Doc. 2026-05787 Filed 3-24-26; 8:45 am] BILLING CODE 3410-16-P

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