Does anyone have an Corps of Engineers approved method for verifying mapped USDA soils types, specifically Lake Charles Clay? Lake Charles clay exhibits hydric characteristics but is not listed on the hydric soils list. If we encounter a soil that *appears* to be Lake Charles clay, how do we verify that it is indeed Lake Charles clay (therefore verifying that the soil is non-hydric)?

In my area, must be confirmed by a licensed soil scientist.

Since I am not a soil scientist, my district will not allow me to check the box "confirmed map type" on the soils data sheet and I also explain in the notes "This soil description not performed by a licensed soil scientist".

Does the soil profile match the "typical profile description" found at http://www2.ftw.nrcs.usda.gov/osd/dat/L/LAKE_CHARLES.html ? The description online does provide the range in characteristics, and the diagnostic horizons found in a profile for Lake Charles soils.

A common mistake in analyzing soil is to rely on soil data obtained in the upper 12-18 inches. A deeper pit may be required to accurately identify difficult soil types, typically 3 to 6 foot deep. This allows observation and sampling of the underlying strata, layers, and other characteristics that define the soil type.

If you are using this for wetland delineation purposes, generally the USACE Districts don't want you confirming the soil mapping unit type unless you are a soil scientist. You may want to contact your local USACE Regulatory office for guidance in this regard. I'm assuming you are in either Texas or Louisiana based on that soil mapping unit, so I'd contact John Davidson at the USACE Galveston District as a good starting place...