Base source: USGS 1:100,000 county base map dated 1975; interpretations derived from soil map constructed 1976.; "Projection and 10 000-metre grid ticks, zone 14, Universal Transverse Mercator. 25 000-foot grid ticks based on South Dakota coordinate system, south zone."; Apr. 1977.; Includes location map. 112 x 92 centimeters Scale 1:50,000