I think it is....but I'm not the informed one on that.

I basically memorized that for my area, any thistle that had a white fuzzy underside was native. That was Oklahoma....

Cirsium altissimum, perhaps.

Here is a link that might be useful: University of Tennessee herbarium

Thanks dbarron...I'll check for white fuzzy undersides...probably true for NC too!

Thanks Carol, that's it!

Yes, it looks like Cirsium altissimum growing in too much shade.