I was doing some research about wasps last year because we had a problem with them building a nest under our breezeway. I found that if you make a fake wasp nest, it will keep them away because wasps are territorial and they will think the territory is occupied. All I knew is that it should be round and gray, so I balled up a grocery bag and covered it with weather resistant duct tape. I broke the hook off a coat hanger so I could hang it. It worked like a charm all summer: no wasps, no pesticides!