Can't say that I've ever seen a garter snake here either. Lots of black and oak. At times I have also had coral and pygmy rattlers much to up close and personal.
They went to whever snakes go. Please don't throw rocks in my direction...I love having the "good" guys, but with 4 curious dogs and living at least 40 miles from the vet the "bad" ones are not welcome in my yard or screen room.