Hartsburg soils are on broad level areas or in large shallow depressions on Wisconsinan till plains, outwash plains, or glacial lake plains. Slope ranges from 0 to 2 percent. The slopes are plane or slightly concave. Hartsburg soils formed in loess or other silty materials. These are the competing Sable soils and the Ipava , Muscatune , Osco , and Tama soils.
Sable soils are on slightly higher positions on the landscape.
The somewhat poorly drained Ipava and Muscatune soils, moderately well drained Osco soils and the well drained Tama soils are on higher or more sloping positions on the landscape. They do not have carbonates within a depth of 35 inches. Where drained, these soils have an apparent seasonal high water table at a depth of 0.5 foot above the surface to 1 foot below the surface at some time between January and May in most years. In undrained conditions, the apparent seasonal high water table is at a depth of 0.5 foot above the surface to 0.5 foot below the surface at some time between November and June in most years. The potential for surface runoff is negligible.