Palo Alto county is located in the second tier of counties from the Minnesota state line and in the fourth tier east of the Nebraska state line. It is entirely within the Wisconsin drift soil area and its soils are therefore all derived from this material, either in its original location on the uplands or as it has been carried by the streams and reworked and deposited on the terraces and bottomlands.
Stevenson, W. H. and Brown, P. E., "Soil Survey of Iowa, Report No. 22—Palo Alto County" (1922). Soil Survey Reports. 30.