If some of the rounds were 36 inch diameter, it is probably Tulip Poplar, which as several have noted is not related to aspens. Tulip Poplar, also called Yellow Poplar or Tulip tree, is one of the largest trees in the east, with really big ones reaching over 150 ft tall. In a lot of places most of the biggest trees are Tulip. I guess occasionally a Bigtooth Aspen could approach 3 ft diameter, but a round that big seems a lot more likely to be Tulip.