Vigar soils have thicker mollic epipedons and more acid sola. Wilmer soils contain sandstone and gravel fragments throughout the sola. Kibbie and Rimer soils do not have mollic epipedons. Lisbon soils contain less than 15 percent fine sand or coarser in the upper part of the argillic horizon. Martinton soils do not have loamy texture in the upper part of the B horizon, having more than 15 percent clay argillic horizons.
Aztalan soils are on glacial lake basins and stream terraces.
The slope gradients typically are 0 to 6 percent. These soils formed in loamy outwash and silty clay loam lacustrine deposits. The mean annual temperature ranges from 45 to 50 degrees F, and mean annual precipitation ranges from 28 to 35 inches. These are the Kibbie , Martinton , and Navan soils. The poorly drained and very poorly drained Navan soils form a drainage sequence with Aztalan soils and are the most common associates in the nearly level and gently undulating landscapes.