I've not had much luck with "homeowner" type remedies such as ones listed above. I've also never seen a Thermacell do squat on Hymenoptera. There are several sprays that will easily kill the intruders and not be a human health hazard. Most labeled products will be of low toxicity with LD50 ratings comparable to two aspirin tablets. Consult the local Extension Center or check the state land grant University for printed recommendations. You could also try dusting the area with DE (Diatomaceous earth) like is often used in pool filters. It's a dessicant and works on many insects.