Q. Whatever happened to the giant murder hornets?
It seems like 2019 was so long ago, but that is when the Asian giant hornets dominated the news (at least for a little while). In case you needed reminding, these were the huge, scary hornets that would attack and destroy honeybee colonies with wanton violence, leaving piles of decapitated bees in their wake. I’m happy to report that, as of December 2024, after no sightings for 3 years, they have been officially declared eradicated from the United States. Thank goodness!
Q. What is the difference between parasitic wasps, paper wasps, mud daubers, and yellow jackets?
Parasitic wasps are extremely tiny – almost invisible to the unaided eye – and are harmless to everyone but their hosts. They are solitary and are attracted to tiny nectar-producing flowers such as alyssum, dill, lantana, and milkweed. The female deposits her eggs onto some hapless caterpillar and goes on her merry way. Eventually, the eggs hatch and the larvae burrow into the caterpillar, eating it from the inside until there’s nothing left and emerging to continue the cycle. Now you know where the plot from the Alien movies came from.
Paper wasps are solitary and non-aggressive as well. They are about an inch long and wispy-looking with long legs and a narrow body that is brown with red or yellow patches. They avoid human contact and tend to build their nests under eaves or other protected spots. These nests are normally under 10 inches long and have fewer than 200 inhabitants. These wasps are not a concern unless they set up shop near a busy location, such as near a door.
Mud daubers are also solitary and build their hard-shelled nests in out-of-the-way locations. Sometimes they will build in the corner of your garage, but the nests are never very big. They are not aggressive at all and will abandon the nest at the end of summer. If you see a mud dauber nest in your garage, you can simply remove it in the fall without fear of retribution.
There are several different species of yellow jackets in California, and all of them are jerks. They tend to build their nests in abandoned rodent burrows or, if the opportunity presents itself, inside walls or ceilings. Each nest can house 15,000 or more insects. If they want to expand their nest and the underground burrow is too small, they simply wet the ground and dig out the space they need. If this occurs in a wall space or ceiling, you may see a damp spot on the drywall, which should be your sign to call an exterminator. Yellow jackets are very aggressive and, once they detect a threat, will relentlessly sting to defend their turf. If you happen to disturb their nest and get stung, retreat immediately before the whole nest comes after you. Don’t try to remove the nest yourself. This is a job for a professional exterminator.
Los Angeles County
Orange County
ucceocmghotline@ucanr.edu; http://mgorange.ucanr.edu/
Riverside County
anrmgriverside@ucanr.edu; 951-955-0170; https://ucanr.edu/sites/RiversideMG/
San Bernardino County
mgsanbern@ucanr.edu; 909-387-2182; http://mgsb.ucanr.edu