S.D. Codified Laws § 10-6-130
All soils must be divided into classes based on soil classification standards developed by the United States Department of Agriculture, Natural Resources Conservation Service. All agricultural land must be categorized as either cropland or noncropland. Soil types with land capability class I, II, and III must be categorized as cropland and land capability classes V, VI, VII, and VIII must be categorized as noncropland. Soil types with land capability class IV may be categorized by the director of equalization as either cropland or as noncropland. The director of equalization must notify the department by November 1 of each year of any changes to the categorization of the land capability class IV soil types. Beginning with the 2023 assessment year, the total acres of class IV soil types classified as noncropland in a county may increase a maximum of twenty percent over the total acres of class IV soil types classified as noncropland in the county in the previous assessment year. The department shall provide each county with soil ratings for all soil types present in the county. The director of equalization shall implement the soil ratings and utilize the ratings as the basis for determining the value of each soil type in the county.
The director may make an adjustment to a parcel pursuant to § 10-6-131.
Nothing in this section prohibits the department from categorizing soil types with land capability class I, II or III as noncropland if one or more of the adjustment factors contained in § 10-6-131 affects the productivity of the soil type, and the reasonable, probable use of the soil type that is physically practical, appropriately supported, financially feasible, and that results in the highest sustainable use of the land, is not harvesting crops or plants produced.
SDCL 10-6-130