This map shows hydric soils in the northern Lake States area. Hydric soils are ones that are saturated or flooded with water during at least part of the growing season, so that "hydrophytic" vegetation indicative of wetland conditions grows on them. The data source is STATSGO, the State Soil Survey Geographic Data Base, from the Natural Resources Conservation Service. More information on hydric soils can be found at http://www.statlab.iastate.edu:80/soils/hydric/intro.html#DEF