

Bees are hairy flower visitors that use nectar and pollen as food.

Honey bees are golden or yellow-brown in color. The natural nesting

site of the honey bee is a sheltered, darkened enclosure. In

addition to the hives of beekeepers, "wild" or "escaped" bee

colonies nest in tree hollows or between the wall studs of

buildings, within attics or in porch roofs. 



Homeowners also may encounter honey bee swarms, consisting of a

mass of worker bees and a queen, that have clustered at an exposed

location. Swarms are temporary; they may stay a few hours or a few

days. Swarms should be left undisturbed; however, a colony nesting

in a tree or building may need to be removed.



Bumble bees are another kind of bee that may need to be controlled.

Bumble bees are large, hairy, black and yellow insects. Though

bumble bees are primarily ground nesters, they occasionally nest in

debris, such as old dressers, little-used equipment stored outside

or similar protected sites. Control may be difficult since getting

an insecticide to the actual nest location (versus the nest

opening) may present a problem. Bumble bees can sting if the nest

is disturbed and care must be exercised.



Carpenter bees bore holes in wood. They resemble bumble bees; the

abdomen is less hairy and they are metallic blue-black in color.

The males are territorial and can be belligerent; however, like all

male bees and wasps, they can't sting. Carpenter bees are most

active in spring, often seen flying erratically near the eves and

gables of buildings. Porches, garages, shed ceilings, railings,

roof overhangs and outdoor wooden furniture are also common nesting

sites. While the damage from a single bee is slight, the activities

of many carpenter bees over years can cause structural damage.



Other bees like sweat bees, mining bees, leafcutter bees and

parasitic bees are encountered occasionally. Females can sting but

seldom do. Mining bees can be abundant locally because of their

STINGING INSECT CONTROL
nest aggregation behavior; hundreds may nest in one area if soil
conditions are right.

Bees Like Flowering Plants!

There is no effective method to keep bees from flowering plants.
Some flowers are unattractive to bees, such as tulips and roses
while other flowers, like azalea, lilac and honeysuckle attract
only the large, longer-tongued bees like bumble or carpenter
bees. Those fearful of bees or who are allergic to their sting
should cultivate plants with less attractive bloom.

WASPS

Wasps are the most serious stinging insect problem to humans and
are the most likely to use their sting. Unlike honeybees, wasps do
not die after they sting. Wasps are less hairy. The young larvae
eat fresh meat in the form of cutup spiders, flies, bees or
caterpillars. Few visit flowers unless they are hunting for
flower-visiting insects.

Yellow jackets are the fiercest and the insect most likely to
sting. Yellow jackets are sleek, yellow and black insects that fly
extremely well. Most nest in the ground, but a wall void nesting
yellow jacket species, Vespula germanica, introduced from Europe,
has increased in numbers in recent years and has become a serious
problem at parks and backyards where it scavenges for food.

Yellow jacket workers present a major stinging pest problem because
their stings cause pain, swelling and discomfort, and they tend to
nest in and around humans. These scavengers are attracted to trash
areas, garbage cans, and areas where sugary fluids are.

Hornets are aerial nesters and, like their relatives the yellow
jackets, make nests of paper. They are longer than yellow jackets
and either yellow and black or, in the most common Delaware hornet,
white and black in color. The nests, which can reach basketball
size by summer's end, are located in trees, shrubs and sometimes on
buildings. Since the nests grow in size with the season, they often
are not discovered until the foliage thins in the fall, well after
the hornets are dead. The European hornet, Vespa, is the largest of
the hornets, it usually nests inside tree hollows.

Paper wasps are thin with shiny, dark brown, brown or yellow
markings. They have long antennae and legs and a pronounced
wasp-waist between front and rear portions of the body. These wasps
build exposed nests of paper cells under the overhang of buildings,
in unused equipment or debris. Occasionally they build in trees or
shrubs. They seldom sting unless disturbed and aren't scavengers.

Other wasps, such as Cicada killer wasps, spider wasps and
parasitic wasps, are beneficial. Efficient prey hunters, they help
keep caterpillars, cicadas and many other pest insects in check. A
parasitic wasp is the main enemy of the Mexican bean beetle that
attacks soybeans in Delaware. These wasps, natural and imported,
are important in the battle against beetle and moth pests.

STINGING INSECT CONTROL

Stinging bees and wasps present a challenge in efficient and
effective control. Control methods at sites where the stinging
insect is most likely to be pestiferous are not available. First,
the stinging insect pest must be identified correctly and its nest
located. Then the nest can be quickly and effectively eliminated to
avoid situations in which people may be stung.

Tree/wall void nest control.

Whether in a tree or side of a building, honey bee, bumble bee or
yellow jacket nests are difficult to eliminate because there are so
many adults present. The actual nest may be some distance from the
entry/exit area itself. Do not attempt to expose the nest, however,
until all, or nearly all, of the adult population are killed.

Spray or dust an insecticide into the entry/exit area. Repeat
application of the insecticide. For some sites, it's better to
apply the spray after dark to avoid being stung by returning
foragers or nest members that respond to disturbances. Nests can be
left to scavenger insects. For wall-void honey bee nests, expose
the wax comb with its honey removed to prevent fermentation of the
honey and the odor it causes. This also diminishes the chance the
honey will run on walls or ceilings.

Nest entry/exit areas should be caulked or otherwise closed to
avoid reuse of the same site. No part of any nest is reused, but
the site itself may still be attractive for a queen to start a new
nest the following season.

Control of aerial nests.

Aerial hornet or paper wasp nests (and the occasional bee swarm or
honey bee nests) can be eliminated by spraying an insecticide
directly into or onto the nest itself. Special aerosols designed to
shoot a stream eight or more feet are sold especially for the
aerial nests. Apply the spray after dark to avoid the possibility
of being stung. If activity persists, repeat the spray another
evening. For round, softball- to basketball-sized hornet nests,
direct the spray into the single, small opening at the bottom of
the nest.

When the population is killed, leave the nest or place it in a
trash bag and discard. If you want the nest for a unique display,
allow the nest to air-dry thoroughly in a place rodents, birds or
squirrels won't destroy it until the odor has disappeared. No nests
or portions of a nest are reused by wasps a second season.

Control of ground nests.

Ground nests of bumble bees or yellow jackets contain several to
hundreds of workers. Like the wall-void nesting site, the actual
nest itself may be some distance from the entry/exit site. Spray or
dust the access area with an insecticide and repeat until activity
ceases. There is no need to remove the nest, it will not be reused.
If a ground bee or wasp chooses a nest site that is inconvenient,
reduce their numbers by spraying the ground area where their
tunnels are visible. Then disrupt the soil surface with a rake or
hoe and spray again. As the bees or wasps attempt to repair the
damage or dig new tunnels, they ingest the insecticide. Often
repeat applications the next season are required.

Choice of insecticide.

An aerosol insecticide is sold that is especially useful for aerial
bee and wasp nests. The can is designed to shoot a stream of
insecticide eight feet or farther. Though this product can be used
on ground nests or nests in structures, it is less effective.

Insecticides labeled for ground insects (for ground nests) can be
substituted or Sevin (carbaryl) used as a spray or a dust depending
upon the situation. For occasional stinging insects inside the
house a flying insect aerosol or fly swatter can be used but be
careful to avoid being stung.

Author: 

Dewey M. Caron
University of Delaware 
Cooperative Extension Entomologist

To the best of our knowledge, all recommendations in this
publication are in accordance with those on product labels.
However, if there is disagreement between recommendations in the
bulletin and what is stated on the label, always follow label
directions.

Commercial companies or products are mentioned in this publication
solely for the purpose of providing specific information. Mention
of a company or product does not constitute a guarantee or warranty
of products by the Agricultural Experiment Station or Delaware
Cooperative Extension or an endorsement over products of other
companies not mentioned.
.
