If it's in a place that is potentially dangerous, it needs to go soon.

If you need to act, you can use one of those 20-foot aerosol sprays available in garden centers and hardware stores. Or you can hire a pest control company.

If it's in a place where it can be avoided until the end of the year, it can remain because the colony members will all die at the end of the year. You can either remove the nest or leave it as is because it will eventually be destroyed by rain and the like.

Thanks Jean. So far, we've left it alone.

If you don't bother them, they won't bother you. I LOVE having a BFH nest in my trees; in my experience, they either pick off or keep the yellowjacket population down. I have seen plenty while gardening, and they have never bothered me. They use their nest for one season, then it's abandoned. We had a nest about 20' above our hot tub years ago; we waited until it frosted to remove it, not knowing much about them at the time. Finally after researching, and seeing other nests over the years, I just coexist with them, unless the nest is in a highly traveled path or is to low to the ground. One year a new nest was started at the top of a 1st floor window; much too close for comfort. It was small, but increasing in size daily. I waited until night time, went outside, knocked it down, then ran like a lunatic. I only saw one BFH, but it moved on and away from where it had started, thankfully.