How do I get rid of a yellowjacket nest in the ground?

Yellowjackets nest in old rodent burrows and soil cavities as readily as in trees and structures (Cornell IPM), and a ground nest is invisible until you step on it or run the mower over it. The vibration brings the colony out at once. A crushed worker releases an alarm pheromone that recruits more (Cornell IPM). Multiple stings at the same spot in the yard, especially near a lawn edge, a stone wall, or a mulch bed, is a ground nest.

Daytime attacks on the nest, when most workers are home and alert. Flooding it with a hose, which drives them out angry and doesn't kill the queen. Gasoline, which is a fire hazard, poisons the soil, and is illegal as a pesticide. Sealing the hole, which just sends them out another exit. Cornell IPM's advice is to destroy nests when they're young in spring, when there are few workers, and leave established colonies to professionals.

The colony dies with the first hard freeze, and only the mated queens survive to start new nests elsewhere in spring; the old nest is not reused (Cornell IPM). If the nest is far from where anyone walks and it's already October, waiting is an option. In August, with kids and a dog in the yard, it isn't.

Ground nests peak in August and September across Nassau and Suffolk, along lawn edges, under sheds and decks, in stone walls, and in the sandy soil of the South Shore. Bobby Bugs treats the nest directly at the entrance and comes back if it's still active. Wasp and hornet treatment carries a 6-month written guarantee.