The modern soil surveys that are the basis for FMMP's qualitative soil ratings range in age, scale, and coverage. Produced by the Natural Resources Conservation Service (NRCS--formerly known as the Soil Conservation Service), each survey was originally published in paper format. Each includes a large volume of information on the potential uses and limitations of soils in a given region.
FMMP now uses NRCS' digital soil data (gSSURGO) to compile the Important Farmland Maps. The digital data provides greater detail and accuracy in soil mapping compared with prior hand-transfer or digitizing methods. The gSSURGO data may have additional soil units that did not exist in the paper version; the lists linked from the attached spreadsheet indicate any changes that have occurred. Historic FMMP files will continue to reflect the original map compilation methods and soil lists.
California Prime and Statewide Soils Links