It looks very much like c. vitalba. I did a little research and there is a vine native to the county here - clematis ligusticifolia. It is likely that, as I see it all over the county. I will have to get a photo of the bloom to verify. Thanks for your help XiaoLong!
Tiffany, I use the term native loosely to describe anything growing wild around here. But you are right - the stinking Baby's Breath that's taking over the county is not native!
