Once upon a time central Illinois was a sea of prairie, sprinkled with islands of forest known as "prairie groves". In Champaign County "The Big Grove" occupied some 6,000 acres in the middle of the county. It was the home of magnificent oaks, hickories, walnuts, and elms that, after standing for centuries, were sawn into lumber for houses and ties to support the rails of the Illinois Central Railroad.
Just a few original giant trees survive of the Big Grove and other timbered areas of Champaign County. Below are two of them, both bur oaks. Their age is unknown, but they must be at least 200 years old.