Looks like a bald faced hornet nest to me. Those guys are unionized with 100% enrollment. Mess with one and you got them all. I had a nest collection at one time and still shoot one out of a tree in the late fall once in a while. I cut the branch off with the .22 rifle. Yes I am that good. Nature centers love to get them less the hornets. The old Coleman white gas lanterns were famous for moth webs up inside the generator cover tube. Bought a lot of them at
garage sales that " just quit working"'