Every spring, paper wasps start building under eaves, inside outdoor light fixtures, on porch ceilings, and around any sheltered spot under a Hill Country roofline. Most homeowners deal with them regularly, and most of the time a single nest is manageable. The situations that get people in trouble are underground yellow jacket nests hit by a lawnmower, nests inside a wall void that no one knew about, and trying to remove a large active nest in full sun with a can of spray.
Quick answer
Paper wasps (umbrella-shaped open nest) are the most common stinging insect around Hill Country homes and will sting if the nest is disturbed. Yellow jackets build underground or in wall voids and are more aggressive. Mud daubers are mostly harmless. Remove active nests after dark when wasps are settled, or call a professional for nests in wall voids, underground, or in high-traffic areas.
Dealing with this right now?
Found a wasp or yellow jacket nest somewhere you cannot safely reach, or dealing with a nest inside a wall? ACI Pest & Lawn handles stinging insect removal across the Highland Lakes. Request a visit and we will take it from there.
See how we handle it on our wasps page.
The Species You Will See Around Here
Paper wasps are the most common. They build open, umbrella-shaped nests from gray papery material and hang them from overhangs, eaves, porch joists, and the undersides of decks. You can see the individual cells in the comb. They are not particularly aggressive away from the nest but will sting repeatedly if the nest is bumped or someone gets too close. They are beneficial predators (they hunt caterpillars and other insects), but a nest directly over a door or next to a play area is not something you want to leave.
Mud daubers build small, tubular mud nests, often found on exterior walls, in garages, and under porch overhangs. They are solitary and rarely sting. Many pest professionals leave them alone unless the nests are in a spot where they create a problem, because they actively hunt spiders.
Yellow jackets are the ones that generate emergency calls. They nest underground, inside wall cavities, or in structural voids. The colonies grow large through summer and become more defensive in late summer and fall. Disturbing a ground nest, especially with a lawn mower, can provoke a mass response. Unlike bees, yellow jackets can sting repeatedly.
Signs of a Nest Inside a Wall
A nest inside a wall void is harder to detect. Signs include wasps or yellow jackets entering and exiting through a gap in the siding, mortar joint, gap around a pipe penetration, or a weep hole in brick. You might hear buzzing inside the wall on warm afternoons. If you seal the entry without treating the nest, the wasps will often chew through drywall or find an interior opening.
Wall void nests should be treated by a professional who can apply product directly into the void and assess whether the entry point can be sealed after the colony is dead.
What You Can Safely Handle Yourself
A small, freshly started paper wasp nest with only a few cells and no more than a handful of wasps can be knocked down and removed in the evening or early morning when wasps are cooler and slower. Wear protective clothing, work at arm's length, and have a clear exit path. Treat with a can of wasp freeze or residual spray, wait until all visible activity stops, then remove the nest.
Do not attempt to remove a nest that is large, in an enclosed space, in a wall, underground, or in a location where you cannot move away quickly if it goes badly. Do not disturb any nest in full afternoon heat when wasps are most active and defensive.
When to Call a Professional
Underground yellow jacket nests, any nest inside a wall or structure, large paper wasp colonies that have been active all season, and any situation near someone with a known venom allergy are good reasons to bring in a licensed applicator. A professional can treat a ground nest with a product that penetrates the nest chamber, treat wall voids with dust formulations that reach the colony, and confirm the nest is eliminated before sealing the entry.
Nests at roofline height on a two-story home are also a practical safety issue even if the species is manageable. Working off a ladder while irritating wasps is an unnecessary risk.