We had a nest under our grape vines one time. They had clipped the grape leaves to make room for landing patterns, and the hole was tiny, but I marked the spot in the day time. Nobody had been stung, but they were to close to the house for comfort. That night I got a funnel, and while all the foraging yellow critters had come home and were in the hole presumably in bed sleeping, I put the funnel tip in the hole and started pouring black powder in until it stopped flowing. Took about half a pound of powder. So now all the yellow jackets are trapped, and I suppose trying to dig out. I have some fireworks fuse, so used enough of that to let me get well away. Then I lit the fuse and backed off out of the way, in fact way back. The powder ignited like an upside down rocket ship, blasting fire out of the hole, burning a huge portion of the grape vines. Then it blew, but not with a large bang like I thought would happen. More of a whoomp, and smoldering nest material was spread out around the perimeter. Got all the yellow jackets, and eventually the hole in the grapes healed over, and yes, I'd do it again. If anyone thinks about copying me, be warned that lots and lots of very hot fire comes out of that hole, so be careful where you do it. Grapes is one thing, burning a house or out building is something else.
