The ridges are broken periodically by outwash channels. The height of the ridges ranges from 50 to 200 feet. Kettle lakes are common, as are linear lakes that occupy abandoned drainageways of glacial meltwater streams. Many of the smaller kettles are now occupied by bog or swamp vegetation.
Many small streams originate near the margins of the sub-subsection.
Well drained and excessively well drained loamy and gravelly sands characterize most of the uplands. Organic soils are common near the margins of the kettle lakes. Organic soils in the kettle bogs can be several feet thick. Oak savanna, also dominated by white oak, with some black oak, occurred on some south and west aspect slopes and on some of the more gently sloping ridges. Kettle depressions supported hardwood swamps, tamarack swamps, shrub swamps, and bog.