Every week you wait, the nest doubles.
A wasp nest in June is a golf ball with a dozen residents. The same nest in August is a football with hundreds — and by late summer, yellow jacket colonies run into the thousands with the food supply tightening and the aggression climbing. The calendar is not your friend on this one, and the size of the nest is the size of the job.
The DIY statistics aren’t a scare line: ladders plus swarming stingers is the combination that fills emergency rooms every summer. A nest at the roofline means working at height, in the line of retreat, against defenders that sting repeatedly and summon reinforcements with pheromones. A suited pro with the right treatment handles it in one visit — that’s the entire sales pitch, and it’s true.
Ground nests deserve their own warning because they’re the ones that find you first. Yellow jackets love abandoned rodent burrows and lawn voids, and the first announcement is usually a mower or a footstep triggering the defense. If wasps are boiling out of a spot in the lawn, mark it from a distance, keep the kids and dogs inside, and call — ground colonies are large and they hit hard.