There are a few species of paper wasps in Alameda County. Their nests have been compared to upside down umbrellas with many holes arranged in a geometric pattern. These wasp nests are usually found under eaves or sheltered patio areas. The European paper wasp is the most commonly encountered paper wasp in Alameda County. They look much like the yellow jackets commonly found here, except the body is slimmer and longer with orange colored legs and antennae. While flying the legs dangle rather than being held close to the body like a yellow jacket.
These wasps are usually non-aggressive but can sting when physically disturbed. Problems can occur when they set up their nest near a doorway or other trafficked area. Usually paper wasp nests in a non-traffic area are allowed to remain undisturbed because they are considered a beneficial insect. They provide a “free pest control service” by capturing pest insects to feed to their young in the nest.
Paper wasps play an important part in helping pollinate plants and kill noxious pest insects, so we recommend only removing the nests that are a danger to humans or pets. “Wasp Freeze” type of insecticide aerosols will saturate the entire nest and quickly kill the individuals in the nest. It is recommended to treat late in the day when most of the workers have returned to the nest. After a treatment you can safely knock the nest down.
If you have a paper wasp nest close to children and pets or near a doorway, please contact our office or make a service for request on-line. Our Biologists will identify the wasps and make control recommendations.