2-3 tbl spoons of Boric acid powder mixed into 1 jug of apple juice. Poor apple juice into used soda cans, and put a twig in there for easy hornet/wasp access. Won't harm bees (they don't like the apple juice mixture). The Boric acid will kill all nests in the area within a couple weeks. . Refresh mixture after 2 weeks if still wasps around. I would kill the nest immediately if you new where it was. But the mixture is a better long term solution.