It probably is, but without close examination it's hard to tell PB from some of the native grape vines. As you probably already know, PB is considered invasive in a lot of places but native grapes are highly desirable.
A pretty reliable way to tell the difference is by the mature fruits. The exterior looks different, and PB fruits have white flesh. None of the native grapes have white flesh. Also, if you see hairs on the underside of the leaves that are only on the veins, that is a good indication it is PB. Finally, the bark of native grapes will peel off in papery strips, but PB doesn't do this.