1. Proper Use of Hydric Soil Terminology

2. Objectives • Explain difference between hydric soils definition, criteria, field indicators, and technical standard. • Define terms important to hydric soil identification.

3. NTCHS • The National Committee for Hydric Soils is represented by • 4 universities • 6 NRCS • 1 representative from USFS, USACOE, USEPA, USFWS, and BLM • The NTCHS makes all decisions on hydric soils.

4. Wetlands

5. Wetlands • Wetlands are delineated for jurisdictional purposes using a 3 parameter approach. • Hydrophytic vegetation • Wetland hydrology • Hydric soils

6. Definition, criteria, indicators and technical standard

7. Hydric Soils

8. Definition • “A hydric soil is 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”(59 Fed. Reg. 35680, 7/13/94)

9. Definition • “that formed under” – hydrology alteration does not make a hydric soil no longer hydric • “develop anaerobic conditions” – lack oxygen, does not have to be reduced • “in the upper part” – generally 12.5 cm (5 in.) in a sandy soil and 25 cm (10 in.) in a fine textured soil

10. CriteriaThe criteria for Hydric Soils (Fed. Reg., 2/29/2012) • All Histels except Folistels and Histosols except Folists • The “saturation” criteria • 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 • show evidence that the soil meets the definition of a hydric soil; • Soils that are frequently ponded for long or very long duration during the growing season… • Soils that are frequently flooded for long or very long duration during the growing season…

11. Growing Season • The portion of the year when soil temperatures are above biological zero at 50 cm. Permafrost: • Hypergelic July – Aug. • Pergelic July – Aug. • Subgelic July – Aug.

12. Criteria • Main purpose is to create hydric soil lists • Not all soils on list are hydric, • Range of characteristics may include both hydric and non-hydric soils • Hydric soil lists are an interpretative rating which must be confirmed by on-site investigations

14. Criteria, cont. • Criteria are not intended for on-site application • Criteria 1 is an indicator • Data that proves criteria 3 or 4 exists can be used to document the presence of a hydric soil

15. Hydric Soil Indicators • Indicators are not intended to replace or relieve the requirements contained in the Hydric Soil Definition • Indicators are used to identify the hydric soil component of wetlands; however, there are some hydric soils that lack one of the currently listed indicators

16. Data Standard for Hydric SoilsRequirements • Water table measurements • Redox potential measurements • Reduced Iron (Fe II) measurements • In-situ pH measurements • On-site precipitation data • Replicates

17. Summary • All hydric soils must meet the definition • Criteria are used to generate lists • Lists are used off-site to determine if an area is likely or not to contain hydric soils • Indicators are used to identify hydric soils on site • Technical standard is used with data • To prove a functional hydric soil exists in the absence of an indicator, and to develop new indicators