Ok, this is new to me, but one of our customers uses spray adhesives to kill wasps. Of course when I heard about this I did a Google search and sure enough the spray adhesives seem to be a great way to get rid of the wasps. If you would like to find out more information and the step by step instructions go to the HOW link below. It sounds like a easy and relatively safe idea. The wasps become coated with adhesive and die, and the material also clogs the nest's entrance, preventing any wasps returning to the nest from getting in.