A week ago, I wrote about a colony of wasps that had taken over the gas grill on my deck. I invited suggestions on how to get rid of them. Apart from what were posted as comments there, I got two other suggestions.
One was to freeze them with a CO2 fire extinguisher, an interesting idea. If I knew exactly where the nest was, under the tarp-like cover, I might have been able to pull it off. Even not knowing that, the fire extinguisher might have had a broad enough effect to work. And it’d be pretty dramatic.
The other suggestion was to put a tray containing gasoline or kerosene below the nest, allowing the vapours to waft up toward it. The vapours would, the suggestion went, kill the wasps.
The latter suggestion had two advantages over any other I’d gotten. It was something I could do with the information I had: I could easily use the broom to slide a tray under the grill from a distance, I did know the approximate area in which to put the tray, and I didn’t have to target the nest precisely. And it was easy to try, with nothing lost if it didn’t work. So I gave it a shot.
I got an aluminum take-out-food tray, poured a half inch of gasoline into it, and put it on the deck a couple of feet from the corner of the grill. I stood back and used the broom to gently nudge the tray beneath that corner of the cover. And the action didn’t disturb the wasps at all — no sentinels came out to check on things. Nice.
To test the situation, I then bashed the side of the cover again with the broom. That brought them out for investigation, as I retreated inside the sliding glass door. I put the broom away and left the tray undisturbed for several days.
Yesterday, I checked on the wasps, and in an initial check it seemed that the gasoline thing worked. There were a bunch of dead wasps in the pan, and when I smacked the side with the broom, no wasps came out at all. All was quiet.
When I was ready to clean things up for real, I went back out and bashed the grill more thoroughly, all around. Nothing. So I wheeled it back into its place, took the cover off, and found the nest. It was a hornet nest the size of a baseball, under one of the side shelves, and it was abandoned. I knocked it off and cleaned the area, and then ran the grill for ten minutes to heat it up fully.
I have the use of my grill again, and it cost nothing but a few ounces of gasoline. Neat!