Changes in agricultural technology, particularly the development of fertilizer chemistry, sharply reduced the economic viability of grassland in Illinois and led to the plow-up of most of the remaining parcels of tallgrass prairie.

After the Illinois greater prairie chicken population dropped to 25,000 in 1933 the hunting season was permanently closed, but this did not halt the decline.

Conservation areas were purchased and set aside in 1939–1944, but the birds died out in these Northern Illinois parcels anyway.

This created an incentive for the private sector to purchase grassland parcels in southern Illinois.

The IDNR manages the State Natural Area with the hope of re-establishing, or maintaining, breeding populations of greater prairie chickens, Henslow's sparrows, loggerhead shrikes, northern harriers, short-eared owls, upland sandpipers, and other endangered or threatened species with a biological tie to grassland ecosystems.