Many pest control professionals consider Carpenter ants the most difficult pest there is to deal with in the industry. With all the training and experience they have, there are some homes that take considerable time and a number of treatments to completely eradicate these destructive insects. Many homeowners will call in a professional after they have failed to solve the problem themselves. This situation is usually more difficult to deal with because the homeowner randomly sprayed pesticides killing the obvious evidence and scattering the satellite nests. Of course this increases the cost. If you are not prepared to spend hours in your attic and crawl space wearing a respirator, rubber gloves, coveralls and a hat, then you may be wise to call a professional to do the job properly.
The process:
Find all of the Satellite nests in the home. (Read about nests on the identification and life cycle page)
Try to locate the "mother" nests and the queens.
Eliminate conditions that made the home a suitable habitat for the ants.
Treat the satellite nests with a suitable pest control method or product.
Don't:
Don't spray pesticides on ants outside the nests. Use a vacuum cleaner inside your home.
Don't use "ant drops, ant poisons, ant traps". Save your money for something worthwhile.
Don't squash foraging ants. Follow them.
Don't rip apart walls or ceilings to find the nests.
How to:
Finding carpenter ant nests requires a lot of time an patience. With years of experience, a professional will know where these nests are likely to be and will look for evidence of frass, the junk thrown out of nests. This is often caught up in spider webs in attics, crawl spaces, basements under decks and around the exterior perimeter under the soffits and below the siding. Sometimes sawdust excavated by the ants from the structure will be noticeable, but not always.
Following ants outside the nest is the best indication of it's location, but ants will often follow channels hidden from the hot sun, rain and your vision. Less than 10 % of the population will ever leave the nests so at times there are very few to follow. Knowing whether the ant you are following is heading for food, or has already eaten and is heading back to the nest is an indicator that some very experienced professionals are capable of seeing.
Listen for them. If your hearing is good and the home is very quiet you may be able to hear the rustling and chewing noise they make. A medical stethoscope is useful but the sound of a refrigerator or even a clock can confuse the inexperienced ear.
How to find the main nests (and the queens):
In some locations it would be impossible to find all the main nests among the trees, logs, stumps, buried wood and roots. Even if these nests are found, removing them can be a monumental task. All satellite nests remain in contact with the main nest. Workers can be seen carrying mature larvae from the overcrowded queen's home to new or established satellites of the colony. If you find the main nest, try to remove it physically. If you put toxic products into it, they may leach into the ground water and contaminate water supplies or fish habitat some distance away.
If you can not remove the nest, try to eliminate any favorable conditions that encourage them to move toward the home. Tree branches, fences, garden hoses, structural wood touching the soil, landscape ties and utility wires all provide an easy route to follow. A very fine dusting of diatomaceous earth around the perimeter base of the home will discourage all insects from crossing it to gain entry. This is short term and should be repeated frequently in the spring, summer and fall.
Pesticides, Poisons and Secret Formulas.
Toxic Sprays: Most pesticides available to the public will kill any insect that they come in contact with while still wet. Once dry, the residual effect is minimal and has very little effect on insects.
Ant Dusts: Diatomaceous earth is sold in a variety of containers with convincing trade names. The basic product can also be purchased in much less expensive plain plastic bags at most garden stores.
Toxic chlorpyrifos is now off the market and illegal to use in Canada and U.S.A.
Boric Acid dust: It is very difficult to inject into a nesting cavity without proper equipment. Do not put it in exposed areas.
Ant Poisons sold over the counter at most hardware stores have little if any effect on carpenter ants
Ant Traps are actually not traps. The little tin cans with holes in the side contain borax. They have no effect on carpenter ants.
Secret Formulas: If you find one that works, patent it immediately. Scientists around the world have been searching for years for ingredients that will attract and kill or repel carpenter ants. Some things that homeowners have tried include cinnamon, cayenne pepper, moth balls, boric acid and icing sugar.
None of them have been proven effective.
Disclaimer: This web page was compiled by a pest management professional, not an entomologist.
As a result, some of the terms used may not be accurate according to scientific terms of reference.
Our objective is to provide basic and interesting information for the average homeowner.