Approach

Abstract

A list of the possible soil taxa containing a diagnostic horizon was prepared from the Keys to Soil Taxonomy (Soil Survey Staff 2010). From this list, a list of soil series containing the diagnostic horizon was obtained from the “Soil Classification Database” (SC; Soil Survey Division 2013a) (http://soils.usda.gov/technical/classification) and “Official Soil Descriptions” (OSD; Soil Survey Division 2013b) (http://soils.usda.gov/OSD) functions of the National Resource and Conservation Service (NRCS) of the US Department of Agriculture (USDA). Case studies were also examined from the literature, which were used in conjunction with OSDs to prepare tables summarizing the role of soil-forming factors and the pedogenic processes involved in development of diagnostic horizons. Primary soil characterization data were obtained from http://ncsslabdatamart.sc.egov.usda.gov/ (Soil Survey Division 2013c).