Is my dog a "bully" at the dog park?

She is submissive to bigger dogs but she plays very rough with smaller dogs and will growl loudly and grab them by the neck as they run. To me this looks like she is being dominant so i take her out of the dog park whenever she does this. Is she being a "bully" if so how can i stop her from doing this?Is my dog a "bully" at the dog park?
Dogs growl loud and grab and try to chase after each other. This is their way of playing. If her rough housing escalates into fighting the this is a sign of dominance and that is when you move her away from the other dogs if she is grabbing and not biting hard enough to puncture or make the dog yelp in pain then this is just normal dog wrestling behaviorIs my dog a "bully" at the dog park?
Maybe or she is just being motherly.Is my dog a "bully" at the dog park?
I would say that she is, just make sure that she does not harm any other dog.