Identifying the nest type:
Paper wasps: Build open, umbrella-shaped combs under eaves, porch ceilings, and window frames. Smaller colonies (20–75 individuals) and less aggressive unless the nest is disturbed·
Yellow jackets: Build hidden nests underground (burrows) or in wall voids and hollow trees. Colonies can reach 5,000+ individuals by late summer and are highly defensive·
Hornets (bald-faced hornets): Build large, gray, enclosed paper nests in trees and shrubs. Aggressive defenders — treat from a distance Best time to treat: Dusk or early dawn, when temperatures are cool and most wasps are inside the nest and less active. Never treat in direct sunlight when the colony is fully active.
Treatment for small nests (golf ball or smaller): A freeze spray (available at hardware stores) or wasp freeze aerosol can kill the nest contact on small earlyseason nests. Knock it down with a long pole after ensuring all insects are dead. Treatment for established nests:
Use an aerosol wasp and hornet spray with a jet stream of at least 15–20 feet. Apply directly into the nest opening at night. Repeat if activity continues after 24 hours. Do not block the entrance before spraying — trapped wasps will seek other exit routes, potentially inside your home.
For underground yellow jacket nests:
Apply an insecticide dust (Delta Dust or Sevin dust) directly into the entrance hole at night. Cover the entrance with a shovelful of dirt the following morning.
When in doubt — especially for large nests or wall void infestations — call a professional. The cost of professional treatment is always less than an emergency room visit.
