ORIGINAL: Wingbone
I don't see any cropland nearby, although I suspect it wouldn't be far. I'd look to see ifI had any swamp oaks or oakridges on or near the site and check those out first. I've hunted the WI river bottoms near Portage and they definately will spend some time there if there acorns.
There is plenty of oak in the bottom - maybe too much as it makes it a little hard to narrow down at times.