I'm wondering if I should have it removed. Do the hornets serve a useful function in the garden? They built their nest in a shrub, so it's at my chest level, which is a bit disconcerting. However, I've walked past it tons of times with no mishap when I didn't even know it was there, so they can't be too aggressive. I discovered it the hard way when I was pulling a vine out of the shrub. Oops. What is your advice?
If the hornets are not a threat to you or others then you should leave it. Hornets feed on a variety of insect pests.
The workers will die back with the first several hard freezes and the queen will overwinter elsewhere.
Here is some information and control if need be on the bald faced hornet and the Europen hornet.