YELLOW JACKET

Identification, Facts, & Control

Latin Name

Vespula squamosa

Appearance

1in long yellow and black much like a umbrella wasp.

Yellow Jacket

Identification and Nest

Yellow jackets are colored similar to the umbrella wasp. To tell the difference, look for the umbrella wasp’s spindle shaped abdomen, and the nest. The nest of the yellow jacket, as it is built larger, consists of several "combs" placed side by side (not just one comb as in the case of the umbrella wasp). The nest may contain as many as 10,000 individuals. In California the yellow jacket nest usually is located underground in the vacated burrow of a rodent; but it can be located in a tree hollow, under a house eave, or similar place. Of course, if the nest is underground, there is less of a gray paper covering over the combs, so the combs are somewhat visible when the soil is removed.

Life History

The queen and males mate in the fall. The males then. die and the queen overwinters in a protected place such as a crack, under loose bark, or occasionally in an attic or similar sheltered location.

In the spring the queen emerges from this protected place and selects a site for a new nest. She lays eggs, then collects insects or other meat and feeds it to the young larvae. She continues this until her first brood becomes young adult workers, and then she becomes a full time egg layer while the adult workers continue to expand the nest and collect food. The ground nesting yellow jackets enlarge their hole in the ground to accommodate their expanding nest. During this time the workers make up almost the total adult population of the colony. They feed on nectar, honeydew, fruit juices or sap as they continue to feed the young larvae insect prey and bits of meat. ln early to mid-August, males and "queens" (instead of the workers that were produced all summer) begin to be produced. They mate nearby.

And with the onset of winter, the males die and the females hibernate. They abandon the nest and it is not used again. Throughout the season the adult food includes liquids high in sugar, such as fruit juices and probably almost any kind of meat, including many kinds of insects.

Click on a species of wasps below to learn further information.

Mud Dauber