Purpose
Ackmore to Zwingle can be used by anyone to look up Official Series Descriptions (OSDs) for the nearly 450 soil series that are named in NRCS soil surveys of Iowa.
The page is also intended to help archaeologists and geoscientists interpret the lithology, relative age, and stratigraphic nomenclature of the surface geologic materials in which the soils of Iowa are formed.
The page classifies soil series according to their sedimentary, geologic, parent materials as described in the Official Series Descriptions (OSDs) and by the PMAT field in the ISPAID database. Classifications are generalized for series that form predominantly in Wisconsinan and earlier geologic materials in uplands. Series that formed predominantly in Holocene alluvium are assigned as appropriate to a lithostratigraphic unit of the DeForest Formation. See Methods for a discussion of the classification process.
Ackmore to Zwingle is not intended for, and should not be used as, a primary source of information for geologic mapping of Iowa landscapes. The classifications provide, at best, a first approximation of the surface geologic materials that might be expected at a location where an NRCS map unit indicates the occurrence of a given soil series. See Appropriate Use for details.