The bowl is a neat idea, but I would have skipped it and just used boiling water- then I wouldn’t need to worry about them coming out a 2nd location and stinging me
Many years ago when I was a kid, there was a huge (maybe a bit bigger than a person’s head) hornet/wasp nest in a tree in my yard. I knocked it down during the winter and brought a chunk of it to school (4th or 5th grade) for show and tell. They woke up in the zip lock bag, so I suspect that their survival may depend on the type of hornet/wasp and how rough the winter is.
I just took out a bald faced hornets nest, about the size of a watermelon. It was up in the second story eaves on the back of my house. Two nights ago, sprayed a can of wasp spray. Next morning, nest was busy as ever. Last night, sprayed four cans. Nothing. Today, used one garden hose with one of those metered, siphon containers, filled with half dish soap / half water; and a second garden hose with a nozel sprayer for a concentrated jet blast. Went back and forth with the two hoses, up on a ladder - repositioning occasionally to get a different angle. After about an hour of spraying, the nest was destroyed (I could just reach the nest with the hoses so water pressure was weak). I was wearing a bee keepers hood but didn’t need it, as they didn’t fly near me at all. I actually felt kind of bad for killing them as they hadn’t been aggressive to date. (but installing a patio next week so needed them gone)
Soapy water truly works. Kills on contact. A taller ladder or a pressure washer would’ve made it a five minute job.
