Natural History

Before Euro-American settlers arrived in the early 1800s, the land which is now Illinois was covered with a 36 million acre wilderness of tall grasses and wildflowers, wetlands, and forests. Of this 36 million acres, 21 million acres were tallgrass prairie.

(Terry Evans)

The tallgrass prairie supported abundant wildlife including bison, elk, wolves, black bears, and hundreds of species of birds.

Within a few short generations of Euro-American settlers' arrival, over 99% of this biologically diverse landscape had been altered by agriculture and urbanization. Although Illinois still is known as the "Prairie State," less than 0.01% of Illinois' original 21 million acres of prairie remains. What once was a vast sea of rich prairie now survives only as tiny, isolated patches. Many species of prairie plants and animals have either disappeared or are in rapid decline due to loss of habitat.

Some preserved parcels of the original prairie are included in the 40,000-acre Prairie Parklands Macrosite -- a constellation of public, private and corporate lands managed to protect diversity -- situated at the confluence of the Des Plaines and Kankakee Rivers, which forms the Illinois River. The Midewin National Tallgrass Prairie, a keystone in that macrosite, adds a large prairie complex that includes dolomite prairies, one of the rarest natural communities in North America, in addition to "grasslands," savanna, wetlands and seeps, upland forests and three streams. The creation of Midewin offers a rare opportunity to regain some of what has been lost, and on a scale that can make a significant difference to the survival of threatened and endangered prairie species.