Corn was an important crop for people who lived in the area that became Illinois before the Europeans first set foot here; it was the staple food crop of the people who lived in the Cahokia area some 1,000 years ago. It was a crop of choice when Europeans settled and started to farm in Illinois, and acreage in the state first reached 10 million acres in 1895. Acreage over the past 100 years has...