There are many species of bees, and virtually all are
beneficial through their activity as pollinators.
However, since bees are capable of stinging, they can
cause a considerable nuisance problem. Bees, as a group
can be distinguished from wasps by the covering of dense,
plumose body hairs.
Ground-Nesting Bees: Two groups of ground-nesting bees
commonly encountered in Michigan are bumble bees and
burrower bees. Bumble bees are easily recognized by their
large, robust, hairy, black and yellow (sometimes orange)
bodies. Bumble bees live in colonies of several hundred
individuals; however, only the queens overwinter.
Burrower bees are small to medium-sized, blackish or
brownish bees with densely pubescent heads and
midsections. Each female constructs a burrow in the
ground and provisions it with nectar and pollen.
Control of ground-nesting bees can be achieved by
treating the nests with an appropriate insecticide. For
bumble bees treat the nest entrance with carbaryl 5%
(dust) or a "wasp and hornet" aerosol; after treating,
close the nest entrance with a handful of moist soil.
Wood-Nesting Bees; Carpenter bees and some leafcutter
bees will nest in wood or in shingle gaps. These bees can
be controlled by injecting carbaryl 5% (dust), ready to
use diazinon or pyrethroid into the nest. After
thoroughly treating, plug the nest entrance with a dowel
of the appropriate size or wood putty.
For a complete listing of suggested control options
for all home, yard and garden insect pests contact your
local Extension Service, found under local government in
the phone book.
Read and follow instructions on the pesticide label.
Heed all warnings. Check with your physician if you have
any concerns regarding your personal health risk.
Controlling Honey Bees
About 5000 people in Michigan keep honey bees as
either a business or a hobby. They produce about $4
million worth of honey and beeswax and pollinate over
$100 million worth of commercial fruits, seeds and
vegetables (not to mention the fruits, seeds and
vegetables in backyard gardens).
Honey bees are not native to North America; they were
introduced by early immigrants. "Wild" honey bee colonies
are the descendants of those bees which escaped from
apiaries. Wild honey bees may choose your attic or wall
void as a nesting site, and this can create a serious
nuisance problem.
There are three types (castes) of honey bees;
workers, queens and drones (males). Most people see only
the workers since these individuals actively gather food
for the colony. Queens (reproductive females) may live
for up to five years, and in their prime may produce 1500
to 2000 eggs per day. Honey bee colonies may contain
20,000 to 60,000 individuals.
There is no way to control the annoyance from
foraging workers around homes. Use caution around
flowering trees and shrubs where bees are active. The
nuisance will subside on its own when the flowers have
finished blooming.
As honey bee colonies become strong in the late
spring or early summer, they sometimes send off swarms
with one queen and several thousand workers. When the
queen tires of flying she chooses a resting place and the
workers cluster around her. Thus, you may find a swarm on
a branch or some similar site on your property. The swarm
will remain clustered together until scout bees have
located a suitable site for permanent nesting. This
usually requires two days or less, after which time the
swarm will break cluster and leave.
Since swarms are a temporary phenomenon, it is best
to allow the bees to leave on their own. In the meantime,
don't allow people to disturb the bees. If the swarm is
in an inconvenient place, it may be necessary to remove
it and it is best to contact a local beekeeper.
When nuisance honey bees establish a nest in your
house, or in a hollow tree next to your house, there are
two control alternatives: remove the bees live or
eradicate them. (Note: honey bees are NOT protected
insects.) You may choose to call for professional help (a
Pest Control Operator or beekeeper) or do the job
yourself. Keep in mind that you must remove the bees AND
their nest because the untended honey will begin to
decompose and/or seep out of the comb. This can cause
odor problems, staining and/or secondary pest
infestations (ants, roaches, wax moths and dermestid
beetles).
Bees can be removed by trapping. This procedure is
effective, although time consuming (4 to 6 weeks), and
eliminates the need to open up the wall to remove comb
and honey. Place a wire mesh cone (18" long with a 3/8"
opening at the apex) over the nest entrance. Wear clean,
perspiration-free, protective clothing and use a bee
smoker. All movement should be slow and deliberate. Place
a hive containing a queen and a few workers as close as
possible to the trap. The bees can leave the building but
cannot get back in and will settle in the decoy hive.
After three or four weeks spray the old nest with a non-
residual insecticide such as resmethrin to kill the queen
and any remaining workers. Remove the mesh cone and allow
the bees to retrieve their honey. Two weeks later remove
the hive and close up the old nest entrance.
Bees can also be controlled by putting an insecticide
into the nest. This is most effective when done in the
early spring when the stored honey is at its lowest level
and the colony is weakest. Locate the nest (tap on the
wall and listen for buzzing), drill a hole into the nest
area, and treat with carbaryl 5% dust, or a ready to use
diazinon or pyrethroid.
For large colonies (2 years and older) it is
suggested that you remove the comb and honey by
disassembling the siding. DO NOT ALLOW ANYONE TO CONSUME
THE INSECTICIDE-CONTAMINATED HONEY! If one swarm of bees
found the site acceptable, another swarm may find the
same area acceptable. In fact, once a site has been used,
it seems to be more attractive to other bees. After
removing the nest, clean the area with soap and water and
apply a fresh coat of paint. Be sure to plug up any
entrance holes and other cracks and crevices.
It is also possible to kill bees by exposing the nest
to freezing temperatures during the winter months.
For a complete listing of suggested control options
for all home, yard and garden insect pests contact your
local Extension Service, found under local government in
the phone book.
Read and follow instructions on the pesticide label.
Heed all warnings. Check with your physician if you have
any concerns regarding your personal health risk.
Carpenter Bee
Two species of Xylocopa, or carpenter bees, occur in
the eastern U.S. Xylocopa virginica is found from Maine
to Wisconsin and south to florida and Texas. In Michigan
it appears to be restricted to the southern half of the
state. Xylocopa micans Lepeleter occurs in the
southeastern states. Carpenter bees are widespread in
their distribution, but are seldom abundant in any given
locality.
The adult carpenter bee resembles the common bumble
bee. Carpenter bees are large (20-30mm), robust, and with
a shiny, bluish-black abdomen. Bumble bees, on the other
hand, have a hairy abdomen that is mostly yellow.
Adults excavate nests in wood. Softwoods (pine,
redwood, fir, cedar, and spruce) are preferred, but they
have been seen nesting in hardwoods (willow and oak). A
"nest" consists of a round entrance hole (0.5 inch
diameter by 1.5 - 2 inches deep) and a system of tunnels
oriented along the grain of the wood. Tunnels range in
length from a half foot to several feet (after years of
use). The bees cut one half inch per day to open the
entrance hole, and then move at a faster pace as they cut
the tunnels with the grain.
Nests are located in porches, eaves, fascia boards,
garages, sheds, carports, fences, window trim, lamp
posts, and other wood objects. Nests are most likely to
be southern or eastern in aspect. They tend to avoid wood
that is painted, whitewashed or covered with bark.
Juvenile (unmated) adults of both sexes overwinter in
the tunnels. They become active when temperatures reach
the 70's in the spring. Mating, accompanied by a strange
"bobbing dance" by the male, occurs in April.
The bees clean and enlarge the nest. They seem to
prefer this to establishing new nests. Therefore, nests
may be used by many generations of bees. Some nests have
been known to have been in use for 14 years. The females
prepare a series of brood cells in the tunnels, providing
each with food ("bee bread" - a mixture of pollen and
nectar), an egg, and a partition of chewed wood. Most
females produce 6 to 8 young. The larvae develop from May
to August, emerging in September. The oldest bee,
developing at the end of the tunnel, emerges first and
must cut through all the partitions and crawl over the
other developing bees. There is only one generation per
year.
There are two principle concerns about the activities
of carpenter bees. One concern is over the possibility of
stings. However, this is actually of minor consequence
since the females (males can't sting) are very hesitant
to sting, and in fact must be held to provoke a sting. In
addition, they are mild stings.
The second concern deals with wood damage. It is
generally more of an aesthetic problem since they rarely
nest in structural timbers. Damage is most severe in trim
and decorative wood on the exterior of the building.
Other concerns include stains of excreta, the buzzing
flight of the adults, the noise of nest construction, and
the attraction of (hungry) woodpeckers.
Carpenter bees are not particularly important as
pollinators. In addition to woodpeckers there are two
species of bee flies (Diptera: Bombyliidae) that are
natural enemies of the carpenter bee. The flies deposit
their eggs in the entrance of the tunnel and the maggots
parasitize the bee larvae.
Carpenter bees are best controlled by placing ready
to use diazinon, or contact sprays of pyrethroids in the
tunnels. After thoroughly treating, plug the entrance
with a dowel of the appropriate size. It may be helpful
to treat the sites used, or most likely to be used, with
one of the residual insecticides mentioned previously.
This should be done in the spring prior to the time when
the bees begin nest construction.
For a complete listing of suggested control options
for all home, yard and garden insect pests contact your
local Extension Service, found under local government in
the phone book.
Read and follow instructions on the pesticide label.
Heed all warnings. Check with your physician if you have
any concerns regarding your personal health risk.
