One of our favorite past times when I was a kid was throwing rocks at the nests and trying to destroy it without getting stung. Good times.
One of the coolest things when I was a kid was watching my old man shoot nests with a 12ga.
Had fun a couple of times. Go out there before the sun comes up and make a torch with a stick and a rag with diesel fuel on it and just hold it under the hole at the bottom and watch the layers burn off.
Usually, I just hit the hole with bee killer early in the morning.
We buy bee killer by the case here at work. There's a lot of pallets of flagstone and fieldstone out there. Most of this stuff is constantly getting moved, but if they hang around too long without getting moved or sold, the bees will make it their home.
