How Do I Get Rid of Ants?
Serious ant infestations, like this one pictured, may need a professional. (Photo courtesy of Angie's List member Justin B., of Meadville, Pennsylvania)
Generally speaking, ants are helpful creatures. Many species kill bed bugs, fleas and other irritating insects, and they don't carry diseases or attack humans. Occasionally, however, these bugs invade homes and apartments looking for food, and evicting them once they've dug in can be a challenge. Both DIY and professional pest removal options are available.
Exterminator prices increase accordingly depending on the severity of your infestation.
Reasons for ant infestation
Ants are in your home for one reason: food. Most feed on sugary or greasy items, which include many of the foods eaten by humans. The common pavement ant (brown to black, 1/10th of an inch long), for example, will set up colonies near driveways or patios and then send out scouts to search for food in your home. They're willing to eat meat, grease, seeds, dead or live insects, and can sting and bite if disturbed.
Carpenter ants (black, up to half an inch long), meanwhile, are looking for protein rather than sugar, and will eat through wood to find nesting locations. Small piles of wood shavings called "frass" found under windows or door frames are signs of carpenter ants.
Keeping ants out
To prevent ant infestations, the first step is keeping a clean house. If you see scout ants in your home, kill them immediately and then make sure you don't have any food left out, all kitchen surfaces are clean, and that there are no obvious ways into your home for these pests.
If you continue to see ants, they've managed to find a way inside. Unlike humans, ants don't need to use doors and will happily crawl through small cracks in your walls or under your windows. To prevent ants from moving in, start by caulking potential entry points, such as window casings. Next, you can lay down barriers like salt or talc under doors to turn ants away, or apply scents such as vinegar, peppermint oil or cinnamon. Bear in mind, however, that anything you put down will also be of interest to pets and children, so be careful what you use.
DIY methods for ant removal
If ant explorers have been replaced by a full-on colony, then you need a plan. Start with soap and water - this will not only kill chemical trails, but any ants it touches. Add citrus to the water to increase its effectiveness. You can also purchase ant baits from local grocery and hardware stores; these use a mixture of ant poison (such as Borax) and sugars to attract, trap and kill ants. Bear in mind, however, that these traps won't work on protein-feeders like carpenter ants, since the sweetness won't interest them.
Getting professional help
Large-scale infestations require professional assistance. Pros address ant problems by locating the colony itself; typically this starts by laying bait traps, which contain poisoned food taken back to the nest. Once found, exterminators can use a variety of techniques including chemical sprays to totally eliminate the ants in your home. In the case of carpenter ants, early detection is critical, since if left unchecked they can cause significant damage to your home. A pest control professional may need to drill small holes in your wall to make sure the entire colony has been eliminated, and will often book a follow-up visit to make sure problems don't reoccur.
How much does an exterminator cost? If you're going to tackle an ant colony yourself, the costs can be quite low - the cost of a liquid ant killer or an ant trap is between $5 and $10. Professional exterminators, meanwhile, can charge between $400 and $1000 to completely eliminate ants. The large difference in cost comes partly because of experience, partly due to materials, but mostly because of effectiveness. DIY treatments may be able to divert ants which have not established a colony, or deal with the scouts send out to gather food, but aren't as effective at long-term removal. A reliable, professional exterminator can make sure ants are completely eliminated and don't find their way back inside.
Editor's note: This is an updated version of a story originally published June 4, 2013.