This forest type is dominant within the subsection where there is adequate protection from recurring fires, generally provided by either steep, irregular topography, broad stream valleys, strings of kettle lakes, or broad wetlands. The loess cap is typically about 2 feet thick.
Ground moraine covers most of the sub-subsection, but there are outwash channels and end moraines.
Streams such as the Rock, Crawfish, Beaverdam, and Fox Rivers act as fire barriers within this sub-subsection. Kettle lakes are also common, both on end moraines and in narrow outwash channels. A silt-loam loess cap covers most of the loamy and clayey tills. Soils are typically Alfisols. Uplands supported sugar maple-basswood forest, with varying amounts of red oak, elm, and white ash.