Elaphe obsoleta. I was preparing to mow the yard, and I found his tail sticking out of the weeds into the lawn. One of our biggest local snakes (they can reach 8 ft in length), they are nonvenomous, and good for getting rid of unwanted rodents and other vermin. This one was only around 4 ft long.
They are also excellent climbers, and are known to prey on birds and squirrels. We have found cast off skins from much bigger snakes than this one in our basement, where at least one sneaks in occasionally.