Yellowjackets and other social wasps

Last Updated: 5/23/2017

This time of year when we venture outside to picnic, BBQ, fish, garden or just sit and enjoy the backyard, we might notice there are some unwanted creatures buzzing around sharing our space.

Most of us have had the upsetting experience of having wasps buzzing around us while we’re eating or working outside and you may have even been stung a time or two. Yellowjackets and paper wasps – considered social wasps because they live and work together in a common hive or nest – were possibly some of the insects you were trying to shew away.

There are a large number of wasp species in California but the two species we encounter most in California are the western yellowjackets and paper wasp. Both species of wasps do a lot of good by killing plant eating insects and nuisance flies but some species also feed on pet and human food, garbage and over ripe fruit.



Controlling paper wasps

Paper wasp nests are very fragile and can be knocked down easily with a stick or a broom. If you remove them early in the year, the paper wasp will generally leave the area and build their nest elsewhere. If you use an aerosol wasp spray for control, choose one that is less toxic to the environment that features an essential oil base and not a synthetic pyrethroid. Be safe and always wear protective clothing and eye protection whenever applying a pesticide. Remember that the paper wasp is doing some of the pest control work for you and if you can tolerate their presence they will usually leave you alone.


Controlling Yellowjackets

Western yellowjackets are the species of social wasps responsible for most of the aggressive behavior and stinging that occurs when their nest is disturbed. Be aware of what attracts wasps and remove the attractive items like pet food, meat, over ripe fruit, open trash cans with food left on plates etc. Place Yellowjackets lure traps in locations far away from patios and food prep areas to draw them away and reduce populations. It is essential that you do not attempt to do any control when the wasps are active. The commercial aerosol products can knock down a few wasps but the chance of getting stung when treating a nest is very possible and even likely.

For help and advice on removing ground-nesting yellowjacket nests contact the Placer County Mosquito and Vector Control and visit www.placermosquito.org for more information.