Cheat Sheet | Carpenter ants and bees: How to get rid of the pests

Posted: August 10, 2007

Bugs are in abundance right now, like the carpenter ants trying to remodel your wooden porch steps without your permission. You want them to leave, but nothing you try seems to work.

Here's some insight into the problem, offered with assistance from a variety of pest-control experts:

Need to know: Carpenter ants, considered the most common pest ants in the northern United States, get their name from the "galleries" they excavate - typically in wet or damaged wood - while building their nests, says Clint Briscoe, a company spokesman for Terminix. Once they are established, however, carpenter ants will tunnel through dry, undamaged wood too.

Color chart: Carpenter ants, which grow up to 5/8-inch long, come in different hues and shades. Depending on the species, they can be black, brown and black, and red and black.

Take flight: Winged, reproductive carpenter ants swarm when they leave existing colonies to establish new ones, usually during warm spring days. After their mating flight, the males often die, and the females (queens) find shelter where they will begin their colony. Nests are often started in piles of lumber, hollowed trees and dead branches. The presence of winged ants indicates an active colony is nearby.

Just add water: The main ant colony must have a constant source of moisture to survive, so it's usually in dead wood outdoors. Indoors, a main colony will have to be associated with a water leak or an overly wet, poorly ventilated crawl space or attic. Satellite colonies can be established in any suitable void - including hollow doors, curtain rods, shower rods, and under attic insulation. These ants will set up trunk trails to the main colony, and to other satellite colonies. (Carpenter ants are primarily nocturnal and rely on chemical trails to find their way to and fro.)

Population explosion: Colonies can include more than 100,000 worker ants, and queens can live more than 20 years. Some members of the carpenter-ant caste system have glycerol, a compound found in antifreeze, in their bodies to keep them from freezing.

Aversion therapy: To discourage carpenter ants, store firewood away from your house and remove wood scraps from around the foundation. Trim dead tree limbs and remove stumps from the yard, and prevent tree limbs and shrubbery from touching the house. Seal any plumbing leaks and roof leaks, and check crawl spaces for moisture. Repair broken or clogged cutters. Direct water from gutters away from the foundation.

Treatment options: Getting rid of your everyday ant is tough enough - eradicating carpenter ants is best left to the professional. Control involves tracking down and treating as many satellite colonies as possible inside and outside the house, as well as attempting to find and treat the parent colony. Exterminators may use baits, but these can have mixed results because of carpenter ants' finicky feeding habits.

Other carpenters: Carpenter bees typically attack bare wood decks, fences, and windowsills. Painting wood will deter some carpenter bees, but it isn't the best solution. More easily controlled than carpenter ants, carpenter bees can be eliminated DIY style, using insecticides available at hardware stores and home centers.

If the wood being attacked is treated with a pest-control product that works over an extended period (known as a residual insecticide), the bees may be repelled or killed. Once holes have been started, nest galleries can be treated. Then the holes can be plugged several weeks later, once you're positive that the bees have been killed.

Want Alan J. Heavens' advice on a home- improvement project or purchase? E-mail him at or write to him at The Inquirer, Box 8263, Philadelphia 19101.

comments powered by Disqus