It's that time of year when yellow jackets (ground bees) make their nests. These animals are mean! They are territorial and when bothered by noise, mowers, leaf blowers, they attack in mass! I've usually had success by putting Sevin garden powder down the hole after dark. Some people put gasoline. I had to tear a stone wall apart to get at this nest....poured gasoline into the nest and lit it!
Burn Baby Burn!