Poor drainage characterizes most of the lake plain and much of the surrounding ground moraine.
The growing season is short, from 92 to 115 days, because the low-lying subsection forms a frost pocket with late spring frosts and early fall frosts. There is also Cretaceous shale, sandstone, and clay near the southwest end of the basin and along the border with the Mesabi Range. Glacial lacustrine deposits occupy much of the subsection. There are beach ridges, but most are not well defined. There is ground moraine along the borders of Glacial Lake Upham, including low drumlin ridges.