Yellow Jackets: The Good and the Bad
Wasps and yellow jackets are beneficial insects. They feed their young on insects that would otherwise
damage crops and ornamental plants in your garden. They can also feed on house fly and blow fly larva.
When the populations peak in late summer and early fall, the yellow jackets' feeding habits become
a problem. At this time of year, they have a healthy appetite for many of the same foods and drinks
we eat. Yellow jacket stings can result in a life threatening situation if the person is allergic to the
The yellow jacket worker is about ½-inch in length with alternating yellow and black bands on the
abdomen. Foraging yellow jackets are often mistaken for honey bees because of their similar color
and the fact that they may be attracted to the same food sources.
Honey bees are slightly larger than yellow jackets and are covered with hairs or setae that are absent
on yellow jackets. Foraging honey bees can be identified by the pollen baskets on the rear legs that
are often loaded with a ball of yellow or green pollen. The yellow jacket has a smooth stinger that
can be used to sting multiple times. Female honey bees have a barbed stinger that can be used to sting only
Underground Yellow Jacket Nest (left)
versus Paper Wasp Nest (right)
Yellow Jackets and Paper Wasps are common pests during the summer months, and it is important
to be able to identify them for multiple reasons. When it comes to these two insects, it can be tricky
to tell them apart.
The Yellow Jacket and one species of Paper Wasps are nearly identical in appearance to the untrained
eye. They are both yellow and black, with the colors falling into a similar striped pattern. The only
recognizable physical distinction between the two is the body type — paper wasps are much
thinner near the waist and is larger than Yellow Jackets. However, unless the insect stays still long
enough for you to get a good look, you will probably not be able to differentiate. It could also be difficult
to the untrained eye if you don't have the two species side-by-side.
The life cycle of the yellow jacket nest begins in winter, when fertilized yellow jacket queens go into
hibernation. Queens hibernate in covered natural locations such as tree stumps and hollow logs,
although they may also choose manmade structures for shelter.
Underground Yellow Jacket Nest
In spring, the queen will emerge and begin to build a nest. When the nest is started, she begins to lay
her eggs. After eggs hatch into larvae, the queen feeds her young with scavenged meat, fish and other
insects. As adults, these first offspring are sterile female workers that expand the nest, search for food
and care for the queen and her young.
After her first generation matures, the yellow jacket queen remains inside the nest laying eggs for the
rest of the summer.
Yellow jackets make nests from a papery pulp made of chewed-up wood fibers mixed with saliva. Their
nests are made up of a series of rounded combs stacked in tiers. Their combs are covered by an
envelope made up of several layers of pulp.
Yellow jackets build their nests below ground in old rodent burrows or similar cavities such as hollow logs,
landscape timbers of in the attics or walls of buildings.
Several hundred to several thousand yellow jackets may be found in a single nest.
Yellow jacket nests are used for just one season and then will remain vacant until the next season.
In the fall, cells will contain larvae ready to become adult males and fertile females. These males and
females will leave their colonies to mate. After mating, males die and the fertilized females go in search
of hibernation locations. Worker wasps perish in winter, leaving the hibernating queen to begin anew
in spring. While nests may last through winter if built in sheltered areas, they will not be used again.
Yellow Jacket Stinger
Yellow jackets capture insects and spiders to feed their young which can include pests like caterpillars,
flies and crickets.
Adults feed on sugar such as the juices of ripening and overripe fruits and honeydew (a sugary substance
secreted by certain insects, like aphids). During late summer and fall, some yellow jackets become aggressive
scavengers around human food and can be common outdoors where food or drinks are available.
Yellow jackets have the ability to sting you multiple times. When a yellow jacket stings you, it pierces your
skin with its stinger and injects a poisenous venom that causes sudden pain. You may also experience
inflammation or redness around the sting a few hours after being stung. Fatigue, itching, and warmth
around the injection site are also common symptoms for many people.