Short answers, pulled from the story.
Settlers from northern Europe and the northeastern United States began plowing up tallgrasses and wild flowers in the mid-1830s after the Black Hawk War ended. By 1849, most species of prairie grass had vanished to make room for crops like soybeans and corn.
The U.S. state of Illinois once held over 35,000 square miles of prairie land but just 3 square miles remain of that original expanse today. Restored prairies now represent only a fragment of the abundant verdure that once stretched from western Ohio to the Rockies.
Prairie grass collects atmospheric carbon dioxide through photosynthesis and stores it deep within its soil when left undisturbed. Deep root systems store large amounts of carbon at fast rates which helps sustain diverse species while mitigating global warming effects across the continent.
Controlled burns with permits are recommended every four to eight years after two growth seasons to prevent trees from encroaching and recycle nutrients into the ground. A wildlife friendly alternative involves burning only a quarter to an eighth of a tract annually using holistic management or livestock substitutes.
Midewin National Tallgrass Prairie sits in Wilmington, Illinois on land once contaminated by TNT manufacturing. The U.S. Department of Agriculture Forest Service administers this site alongside the Illinois Department of Natural Resources since 1997.