See comments for rare plants. The fauna also reflects the isolated, relict watersheds of the section, which have rich fish and mussel faunas, as well as dragonflies and mayflies with restricted distribution. The southern half of the section contains many significant bat hibernacula. This section has more natural areas than any other in the three States, reflecting the large number of rare plants and animals found here, as well as the unique topography. Natural Areas are listed under subsections.
Grazing is common in woodlots in both Minnesota and Wisconsin.
Logging pressure on oak saw logs is high due to the depressed farm economy and strong timber market, and there is a concern about future logging on federally managed flood-plain forests. Development pressure is increasing on the blufflands, especially on the Mississippi and lower Wisconsin Rivers. Mesic prairie has been almost eliminated. Section IV is bounded on all sides by more rolling topography.