State University Extension
Home Maintenance And Repair - 01500544
The presence of carpenter ants is usually a symptom of a problem a
water leak causing wet/punky wood. Therefore, it is important to
determine the reason the ants are nesting in the structure, than to
kill them. Your home is much more at risk from water damage, which
attracts carpenter ants, than the ants themselves. Do not be pressured
into buying a long-term spray control program by a pest control company
that does nothing to locate the nest and link the symptom to the cause.
Carpenter ants are common invaders of dwellings in Michigan. These ants
are opportunistic feeders and invade households looking for food
sources; primarily in the kitchen and areas where food is eaten or
stored. Like most ants commonly found around the house, carpenter ants
prefer sweet and greasy foods.
Prevention of a carpenter ant infestation requires that you do at least
two things: maintenance of the structure to deny suitable habitat and
maintenance of the structure to deny access.
Periodically inspect your dwelling for water damaged wood and take the
appropriate steps to correct the problem. Take special care to
carefully inspect areas where water and other pipes go through walls,
base of toilets, around bath tubs and the base of shower stalls.
Regularly caulk, weather strip or otherwise repair openings to the
out-of-doors such as around window panes, where pipes go through walls
to the outside and the basement, and door jambs. Check your roof for
water damage under shingles and the slashing around chimneys,
standpipes, and other roof and bathroom vents. The use of a bait will
lure the ants to feed and you will then be able to watch the ants come
and go and ultimately determine if they are coming from the outside or
have a colony in your dwelling.
Carpenter ants like sweet and greasy foods. Our bait recipe is two
parts jelly or jam an one part canned dog or cat food (the cheaper the
better). The portion doesn't need to be more than a half a cup. Situate
the bait in the area where you have been observing ants, but safe from
pets and children. The ants will start coming to by your bait. Observe
where they are going. When you see that they are regularly feeding on
your bait it's time to change the recipe. Mix a new batch of bait, but
now mix boric acid in with the pet food/jelly mixture. The proper
proportion is a tablespoon to every cup of mixture. The ants will carry
the "poisoned" bait back to their colony, pass the food around, and
eventually the colony should be destroyed.
Indoor formulations of chlorpyrifos can be applied to areas where nests
have been found. Great care should be taken when using these poisons in
the home. Read and follow instructions on the pesticide label. Heed all
warnings. Do not use these materials in your home if you have small
children, fish in an aquarium, or pet birds. Check with your physician
if you have any concerns regarding your personal health risk. Other
recommended indoor pesticides are propoxur RTU and baits:
hydramethylnon and propoxur and boric acid.
If you choose to use an insecticide out of doors, a diazinon 25% EC
formulation sprayed completely around the outside foundation and
adjacent one foot of soil is suggested.
If you have taken all of the steps to prevent or eliminate these
insects through sanitation and/or an application of insecticide and
still seem to have an infestation, you may have to implement a more
vigorous control program or consider hiring a professional service.
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.
Revised by Tom Ellis, M.S., Department of Entomology
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educational purposes only. References to commercial products or trade
names does not imply endorsement by MSU Extension or bias against those
not mentioned. This information becomes public property upon
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status. Issued in furtherance of MSU Extension work, acts of May 8 and
June 30, 1914, in cooperation with the U.S. Department of Agriculture.
Thomas G. Coon, Director, MSU Extension, East Lansing,MI 48824. This
information is for educational purposes only. Reference to commercial
products or trade names does not imply endorsement by MSU Extension or
bias against those not mentioned.
information.was reviewed as
of June 2008. For more information about the contents please
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