I'm starting to notice the wasps showing up in our garden, and wasp deterrents shaped like wasp nests showing up in the hardware store.
In the Bag
I have used various toxic methods in the past (the most effective being to call an exterminator), I am now in a kinder and gentler frame of mind. Somehow, somewhere, I'd heard about using an inflated paper bag as a deterrent. The idea being that the wasps see the nest as a rival and therefore avoid it. It seems like one of those "it's crazy enough that it just might work" scenarios, but I wanted some scientific evidence.
I've heard many people with anecdotal evidence that it worked. I tried it out once a while ago with mixed results. It seemed that so many other factors could be involved, including the wasps getting full, the weather changing, the food being removed (so the wasps weren't attracted any more). It's not a simple situation because of the many kinds of wasps, and their different behaviours which change under various conditions. People also seem to have trouble identifying flying insects when they are frantically swatting them.
I came across a commercial version made of material, which looks more like a an actual wasp nest (round and gray). They sent me a paper done for them by a consulting firm, testing the devices near wasp lures and they appeared to be effective. The data, however, only indicated the presence of absence of wasps without identifying the species or counting the number. As well, I still don't know if it is any better than a paper bag.
I contacted some entomologists and received responses from five. Only two had even heard of this practise, which was surprising to me. All were skeptical about its usefulness, though a few acknowledged it was an interesting idea. I guess that is the way a scientist is supposed to think about questions. And I guess you don't get big research grants to look at paper bags. One pointed out that he had not seen any evidence that species of local yellow jackets are especially territorial and that the one that makes a nest resembling a paper bag (confusingly known as the bald-faced hornet) is the least aggressive. Dr. Richard Ring expressed skepticism, but added, "after a 45-year career in entomology I never cease to be amazed by the new things I find out about insect biology and behaviour."
After getting stung in the head last summer, my daughter seems reluctant to participate in any wasp related studies. So if any of you have the inclination to do a controlled test of a paper bag or a commercial device, please share your results.