Problem Hydric Soils

Saturated, but not Reduced Low organic matter –e.g., sands No iron –e.g., E horizons of Spodosols, sands Oxygenated water –slopes, sands and gravels, “perched” water tables Cold temperatures High pH, salinity

Problem Hydric Soils Dark A horizons > 12” thick –Mostly Mollisols (Mollic epipedons) –Dark colors from high OM mask redox features Thick, sandy E horizons –Most often Spodosols –Lack of Fe in E horizon Soils with little development –Usually Entisols Sandy soils, low OM, recent deposits on floodplains

Problem Hydric Soils Heavy clay soils –Most are Vertisols or Vertic subgroups Dark colors from high OM mask redox features in surface layers Constant churning of soils may disrupt features and/or gray colors Soils with perched water tables and bright subsoils

Problem Hydric Soils Parent materials –Reddish colored e.g., materials derived from Mesozoic sediments –Gray colored e.g., lacustrine and marine deposits –Dark colored e.g., Carboniferous material

Approaches for Delineating Problem Hydric Soils Field Indicators of Hydric Soil in the United States’ regionally specific indicators for problem soils. Observations made along a hydrologic gradient. Research and local soil scientist’s knowledge of problem soils. Hydric soils lists.

Landscape Transect Approach Soils occur as a continuum on the landscape Describe a known “wet” soil Describe a known “upland” soil Use judgment to discern the boundary WettestUplandWet???

Beware of lithochromic mottles

Be cautious of reduce matrices If a soil is saturated at the time of excavation, make sure you do soil colors as you dig the soil. Reduced matrices will change color upon exposure to air. Therefore, if you wait to do soil colors, you may not get the colors you expect.

Which soil is the hydric soil?

Upland soil in Marl. Hydric soil in marl. Note the organic streaking.

Which soil is the hydric soils?

Sandy upland soil with a thick E horizon. Sandy hydric soil with thick dark surface and yellow sands underneath.

Which soil is the hydric soil?

Upland gray parent material soil. Hydric soil with a reduced matrix that has brightened upon exposure to oxygen.

Red Parent Material

Redox depletions along ped faces

F3 in Red Parent Material

Relict features in red parent material

Glauconitic upland soil that meets F6

Wet soil containing glauconite

Graphitic phyllite parent material

Gray bedrock

Latort profile

Diatamaceous earth

Gray E horizon in a coarse loamy upland soil

“Dirty” E horizon in a wet spodosol

“ABLS” soil found in freshwater wetlands adjacent to tidal areas

“ABSS”

Piedmont floodplains

Buried hydric soil on Piedmont floodplains

High pH/High Salt/High Gypsum

Still not sure? Landscape position, landscape position… –compare soil profiles from various landscape positions Look at the entire soil profile –top to bottom, not just 10” or immediately below the A Indicators of wetland hydrology and a hydrophytic plant community –herbaceous layer is often more diagnostic than trees When all else fails....

… MONITOR !!