Carpenter bees are large, yellow and black (or blue-black)
bees that become active in early spring. This bee is commonly 2/3 to 1 inch long,
usually with a shiny abdomen and a yellow thorax. Its look-alike cousins
(bumble bees) have a fuzzy abdomen. Although it is rare to be stung by one, their sheer size
is scary and people generally stay clear of them. Bumble bees do not
bore into wood, as do carpenter bees.
Carpenter Bee Biology
Carpenter bees get their name from their ability to drill through wood
and nest in the hole. Their drilling creates a near-perfect hole, approximately 1/2
inch in diameter. The hole is usually located on the underside of the wood surface;
including siding, soffits, decks, overhangs, fence posts and window frames.
Although the hole appears to be only an inch or two deep, it rarely ends there.
- The female carpenter bee will turn 90 degrees and bore a channel from 6 inches
to as long as 4 feet. This channel serves as a main corridor from which she will
drill small chambers a few inches deep. These chambers become egg holders. She
will deposit an egg, bring in a mass of pollen for the newly hatched larvae to feed on,
and then seal it all off to ensure it's development before she repeats the process for the
- The male spends most of his time flying around the nest playing guard.
This is ironic as nature has left him ill prepared: he has no stinger! Only the
female can sting. Simply killing the male will not solve your problem. You
must treat the nest.
Half-inch, round holes appear, and piles of sawdust are found underneath.
Along with the coarse frass (sawdust) found underneath the nest entrance, there are
usually dirty-yellow streaks of fecal matter staining the wood below the hole. If
you are near a nest, you will likely be buzzed by the male carpenter bee on
guard. He is loud and aggressive, but remember that he does not have the ability to
sting you. The female can sting but she is normally very docile. A single
pair (male and female) occupies each nest. It is not uncommon to find several pair
of carpenter bees nesting in one structure. They frequently nest near each other and
often in the same area year after year, causing extensive damage. You may find old
holes near newer ones. Sometimes the female will renovate an old nest gallery and
To control carpenter bees, do not concentrate on the adults. The annoying male
bees are easy to kill with a wasp freeze such as PT515. However, killing the male will do
nothing to stop the cycle. You must treat the nest with a product which will have a long
residual killing time. If you spray liquid residuals in their hole, you may kill the
female bee. The eggs are protected, however, and six to twelve months later the larva will
emerge. Since liquids are absorbed by porous wood, they will be gone when the larva hatch.
This means the larva have a strong chance of survival.
To insure complete control, use a
dust called Drione. It has a desiccant action and can remain
active up to 3 months in the nest and the nest galleries. When the larva emerge they will
be dehydrated by the Drione Dust. Apply the Drione (using a Crusader
Duster) to the nest openings and deep inside the cavities drilled by the carpenter
bees. This will kill any emerging carpenter bees and larva in the future. Since the holes
can penetrate several feet, you should use an applicator like the Crusader Duster. This tool will help you to apply
the dust with enough force to reach deep in the nest where the eggs and larva will be
You should also treat any wood surface that you wish to protect with Defense
SC, Tempo WP or with Cyper
WP. Wettable powders (Tempo WP
and Cyper WP) are used extensively by pest
control operators throughout the United States for most of their monthly, quarterly or
once-a-year pest control accounts. These products are active against many pests
including carpenter bees.
Cyper WP costs less and has a better knock-down or initial kill than Tempo
Tempo products have a better label for treating shrubs, ornamentals, etc.
Both Cyper and Tempo products will kill carpenter bees.
Defense SC is a more versatile product that can be used in more areas than
other insecticides. To the layman, differences in control of
carpenter bees is about the same whether D-Fense or Cyper WP is used for the
job. Professional pest control technicians will usually use wettable
powders (WP) for longest possible
residual but prefer to use Defense SC,
Suspend SC or Cynoff
EC when control is needed without a visible residue on darker
If your home has cedar siding or is a log home:
Wettable powder formulations will leave a visible residue on dark surfaces which is
undesirable for some people. Cedar and log homes may also be bombarded with
carpenter bees which requires special attention. Most of our customers who have
these types of homes prefer to use Demon EC or Cynoff EC for their carpenter bee
elimination. Both of these products contain Cypermethrin
(an active ingredient which gives excellent knock down of carpenter bees) without leaving
a visible residue. These products are also much cheaper to use when treating larger
areas or where high volumes of insecticide spray is required. When treating these
larger areas (on log or cedar homes) use a hose-end sprayer for application. This
allows you to treat exterior walls with greater ease and reach higher areas without having
to use a step ladder. For severe infestations of carpenter bees on
cedar and log, you will need to spray twice (2 weeks apart) the first month.
After your spray has been allowed to dry, apply your Drione Dust to all possible carpenter
bee holes or entry points. Repeat spray and dust as necessary.
Choose the product that best suits your overall needs for pest control in and around your
home or business. Tempo WP and Cyper
WP are wettable powders (powder
concentrates that are mixed with water for spraying for various insect pests) which are
odorless and give at least 90 day residual action indoors. Cynoff EC and Demon
EC are liquid concentrates which give about 30 days residual and no visible
Defense SC gives up to 60 days
residual without the visible residue seen with wettable powders.
Mix 1/2 to 1 ounce of these liquid concentrates per gallon of
water. Cyper WP or Tempo WP are mixed at the rate of 2 scoops per gallon when
controlling carpenter bee infestations; spray on any wood surface you wish to protect from
carpenter bees or where they may want to bore holes and create galleries.
One gallon can
treat up to 1000 sq./ft. This application rate works well when treating cedar homes and
log cabins. These structures are particularly subject to carpenter bees.
If you tend to
have recurring carpenter bee problems every Spring or Fall, may have to do more spraying.
This will deter future infestations of many pests, including carpenter bees.
Apply your wettable powder insecticides once every 4 weeks in the spring when they are
most active. Once a month applications throughout the summer will probably provide
protection but do not forget your fall application. Although rain and humidity will break
down the chemical, it is active enough so that even trace amounts will help chase
carpenter bees, wasps and hornets away.
Use a pump sprayer to do the treatment. ( Chapin Sprayer )
Start treating high on the siding under the eaves.
Since the product will run down the
side of the home, you will get the best coverage this way. The most economical way to
spray is with a garden pump sprayer. Our Chapin sprayer is capable of reaching up to 30
feet high. Product comes out slowly and it may take a couple of gallons to treat your
home. However, the pump sprayer avoids excessive waste.
If you have a lot of area to
treat and are not concerned about wasting some product, use a 20
Gallon hose end sprayer with a liquid
concentrate Cypermethrin (Demon EC, Cynoff EC,
Carpenter Bee Kit #3
Bee Kit #9 are perfect for larger jobs or homes
constructed with cedar siding or logs. A hose-end type of sprayer is used by
pouring 6 to 8 ounces Cypermethrin product, fill with water, hooking it to your garden hose and then depressing the
This releases the water from your hose which in turn siphons out the required
amount of Cypermethrin to provide the correct solution. Garden hose application is much
easier to use than a pump sprayer. Many times the water pressure
enables spraying higher
than the pump sprayer. Expect a small amount of waste when using the hose end sprayer.
On a special note,
do not use a "Miracle Gro" or other "no-clog" hose end sprayer which
lets water mix with the concentrate. These sprayers are designed for water soluble
fertilizer and will not work for this application.
When Spring has sprung, insects will
rebound from a long and cold winter. The carpenter bee is one such pest. Treat their nests
directly with Drione or Delta
Dust to insure long term control. Use Cyper
WP or Tempo
WP on decks, overhangs and fence posts in the Spring to stop further nests from
starting. A little prevention will go a long way in reducing the amount of unsightly
damage caused by carpenter bees.
Carpenter Bee Kits
Three pest control kits to choose from:
Carpenter Bee Elimination Kit: This kit
is for controlling carpenter bees, spiders, scorpions, roaches, carpet beetles, clothes
moths and other pests that wander in from outdoors, invading your home. Save $$
when ordering this kit!
The carpenter bee kit contains:
- 1 pint D-Fense SC (same as Suspend)
- 1 Chapin 1 gallon sprayer
- 1 Crusader duster
- 1 Lb. container of Drione Dust
Carpenter Bee Kit #1
If you already own a quality sprayer, you need
Bee Kit 2. This kit contains the same items as Carpenter Bee Kit 1, but without the
1 gallon sprayer.
Order Carpenter Bee Kit #2
Bee Kit #3 contains
a quart of Cynoff EC, 1
pound of Drione Dust,
a Crusader Duster
Gallon hose end sprayer.
With Carpenter Bee
Kit 3, your insecticide (Cynoff) is applied with a sprayer that attaches to
your garden hose. Once treated surfaces have been allowed to dry
thoroughly, any carpenter bee holes can be dusted with Drione Dust.
Carpenter Bee Kit #3
Professional Pest Control Products
6920 Pine Forest Road
Pensacola, Florida 32526
Homes, Log Homes