Re: Master horizon for fill

Designations for horizons and other layers are defined in the Soil Survey Manual, chapter 3, page 117-130. (Master horizons ""W"" and ""L"" have been added as well as the subordinate distinctions ""ff, ""j"", ""jj"", and ""ss"" and ""co"", ""di"", and ""ma"" used only with the ""L"" horizon. The Field Book for Describing and Sampling Soils and the Keys to Soil Taxonomy 8th Ed. also have abbreviated and somewhat updated definitions.

The only master horizons that are appropriate to use with mineral soil consisting of unaltered fill material are ""C"" and ""A"" and A only if the material exhibits ""properties resulting from cultivation, pasturing, or similar kinds of disturbance. The suffixes ""d', ""g"", and ""p"" can also be used with these kinds of soils.

I realize that these horizon designations are not entirely satisfactory. We have formed an international committee on the classification of anthropogenic soils (ICOMANTH) to develop improvements to the classification of strongly, human altered soils. Proposals to change or add horizon designations as well as recommendations on for these kinds of soils could be proposed to Dr. Ray Bryant, chair of ICOMANTH.

The ICOMANTH web site address is shown below:

http://wwwscas.cit.cornell.edu/icomanth/