Polistes dominulus

"...these are indeed Polistes dominulus females, and they appear to be doing an aggressive behavior called "grappling", which sometimes escalates to the point where it becomes a "falling fight" as the grappling wasps fall to the ground in a writhing ball. The females do this mostly in early spring when initiating new colonies, which they can do either solitarily or in groups. A group of nesting females eventually forms a linear dominance hierarchy, and this type of aggression may help determine who gets the top spot."
Thanks to Dr. Aviva Liebert for providing this information.