I found it! Let me answer my own question Looks like wild clematis is ok but regular, and I guess that means the nursery brand of clematis is toxic to torts. Too bad, I have a couple of huge clematis bushes.
I've found conflicting info on this plant. One site says clematis is ok and yet another says toxic. Neither gives latin name, so to be safe stay away. I have never had any animals (deer, rabbits, ect) browse it on my place, so it is probably at least unpalateable.