This just isn't true. The Eastern half the US was heavily deforested by colonization, but that's really not true in the midwest. It was prarie.
There are actually a lot of researchers who believe that the Native peoples were keeping the forests back via controlled burns, since grassland is better for hunting and agriculture, and the forests have regrown substantially _since_ most of the indigenous people died via disease.
Indiana is the beginning of the Eastern forests. Prairie starts in Illinois and extends over most of the Midwest and runs North/South along the Rockies well into Canada and down to Texas, New Mexico.. nice map: https://en.m.wikipedia.org/wiki/Tallgrass_prairie#/media/Fil...
Like, I'm not saying wikipedia is an infallible source of truth, but I'm not exactly arguing for ancient aliens here:
> In the Eastern Deciduous Forest, frequent fires kept open areas which supported herds of bison. A substantial portion of this forest was extensively burned by agricultural Native Americans. Annual burning created many large oaks and white pines with little understory.[10]
There are actually a lot of researchers who believe that the Native peoples were keeping the forests back via controlled burns, since grassland is better for hunting and agriculture, and the forests have regrown substantially _since_ most of the indigenous people died via disease.