Bruce Township was, at the time of its original survey, well timbered with hickory, ash, elm, maple and linden, with some cedar and tamarack along the marshes or streams and a few wetland areas. At the time of the early settlements, an artificial structure, circular in form, was found in Section 3. It appears to have had three gateways or open passageways some ten feet in width, and the area included in this work was a little more than an acre, and the indications led to the conjecture that this and works of similar character were built for some defensive purpose by a race long since extinct.