Carpenter ants in house? Carpenter ants can be a very difficult pest to dislodge because of their colony structure: nests in the home are often satellites of parent colonies located nearby, in rotting logs or other moist wood, so unless all the colonies are found and eradicated, the ants will return…and return…and return.
In general, removing carpenter ants that are in the house often requires professional pest control, but below are a few DIY measures you can attempt.
First, make sure to make a positive identification so that you know you are actually dealing with carpenter ants. Carpenter ants are large, as much as half an inch long, and sometimes have wings. (Don’t confuse them with termites–termite wings are much longer, and brittle. ) Ant bodies are usually black, but sometimes dark reddish or brownish. Because the burrow into wood to nest, you may see sawdust around the affected area, but the nest area itself will be clean.
Once you are sure that what you have are carpenter ants in house, try some of the following measures to avoid the need for a professional pest control company.
Eliminate carpenter ants in houses
- Liquid ant baits, such as Combat Source Kill Max Ant Killing Gel, are sometimes effective against carpenter ants. These slow-kill formulas are designed to attract foraging ants to carry the poison back to the colony to destroy the nests. However, the baits in these traps are not carpenter ants preferred diet, so they are not always effective. Some homeowners report success in eliminating carpenter ants in house with homemade baits using boric acid and bait foods such as peanut butter. Remember: If using ant baits, expect to ssee many more ants before their numbers are reduced, and resist the urge to kill them! These ants are your allies in carrying the poison back to the nests.
- Specially-formulated sprays that target carpenter ants (eg TERRO® Carpenter Ant & Termite Killer Aerosol) may help control problem areas. However, these pesticides kill on contact, and will not help with the parent or other satellite nests. Sprays may be more effective if you can follow the trails back to the nests and locate and eliminate the actual nests.
- For a treatment that can reach nests within walls and cavities, Penn State scientists recommend dust formulations like diatomaceous earth, boric acid, or silica aerogel that can be blown into holes, and are not dangerous to humans or pets. Diatomaceous earth can also be sprinkled directly on the ground and near potential entry points, both in and out of the house.
Preventing a recurrence
- Remove all waste wood, stumps, etc. that are near the house. Try not to let any plants actually touch the house, and keep firewood outside when not in use.
- Because carpenter ants infest wet or rotting wood, make sure any wood structures in or around the house are kept properly dry. For example, make sure the roof and gutters don’t leak, and that decks are made of either painted and sealed or pressure-treated wood.
If the above self-help steps are not enough to eliminate the carpenter ants in your house, you will probably need to call a professional pest control company, which will be able to help you locate and exterminate all the nests in your area.
“Carpenter ant Tanzania crop” by Muhammad Mahdi Karim. https://commons.wikimedia.org/wiki/File:Carpenter_ant_Tanzania_crop.jpg#/media/File:Carpenter_ant_Tanzania_crop.jpg