The loess cap is typically about 2 feet thick. It also occurred on some steep end moraines, where soils were excessively drained and no major wetlands served as fire breaks. Oak forests are typically found on ground moraine with minor streams or wetlands forming fire breaks, or on relatively steep, dissected end moraine without major fire breaks. Fire was important in maintaining oak savanna and forest. The entire sub-subsection is intensively farmed.
Forest persists primarily on steeper end moraines and in poorly drained depressions.
Of the extensive original oak openings, only small preserves remain. The landscape is heavily disturbed and severely fragmented.