There are only a few different insects that have the potential to cause structural damage to a home.
Of course, the most damaging are termites. In addition, there are Powder Post beetles that actually feed on hardwood material. These beetles are mainly associated with cabinets and furniture.
Another group of insects that attack structures are carpenter ants. Of the three groups, termites are the most serious because they have the potential to cause greater structural damage in a given amount of time than the other two groups of insects. Powder Post beetle problems tend to be very isolated and infestations are generally a result of the insects being brought into an area such as the furniture cabinetry material without the homeowner’s knowledge. However, carpenter ant problems have a greater potential to be wider spread and can develop almost anywhere. I know this because from experience, I have them around my house.
Some confuse ants with termites, which will not begin to swarm until the temperatures reach the mid-80s, which is usually mid-April. Carpenter ants are similar in appearance to other ants in that they have small pinched-in waists much like wasps. Carpenter ants are quite large, from 1/4 to 3/8” long; dark brown to black, although some may have a red or yellowish coloration.
Carpenter ants are active indoors during many months of the year, usually during the spring and summer. When ants are active in the house during late winter and early spring (February-March), the infestation (nest) is probably within the household.
When carpenter ants are first seen in the spring and summer (May-June), the nest is likely outdoors and the ants are simply coming in for food. The natural food for ants consists of honeydew from aphids, other insects, and plant juices, but they will readily forage for water and food scraps within the house.
Carpenter ants usually nest outside in moist wood or partially decayed wood. They prefer the “softened wood” to hollow out their nests called “galleries.” These galleries are quite clean and have a sandpaper appearance. Termite galleries are rough looking in comparison. Many times you can see “sawdust” or frass near these galleries. Outdoor nests can occur in stumps, hollow logs, fence posts or in dead portions of standing trees. However, cracks and crevices may be used to start nests in sound wood. Many times the carpenter ants that you see inside your home are simply foraging for food.
The secret to control is direct treatment of the nest. To locate the entrance, look for the piles of sawdust. Because worker ants move from the nest to forage for food, their movements may help you find the nest opening. Inspect the entire structure and surrounding grounds because the nest or nests may be outdoors as well as in the structure.
If you find the nest entrance, use a dust formulation of an appropriate insecticide. Introduce the dust into the nest through the entrance hole using a hand duster that has a tube with a tip which fit snugly into the entrance. It may be necessary to enlarge the hole to fit the duster. You can make a duster from a flexible plastic bottle equipped with a tube tip. Fill the bottle no more than one-third full, insert the tip in the entrance hole and inject the dust by alternately squeezing and releasing the pressure on the bottle. A dust containing 5 percent carbaryl (Sevin) or 1 percent bendiocarb (Ficam) is recommended for this treatment.
There are new baits and other treatment technology available to pest control operators for more efficient carpenter ant management. If you can’t find the nest entrance, spray around the infested area with a labeled insecticide. One spray application may not eliminate the infestation since only foraging workers will be affected. Additional applications may be necessary to continue to kill these exposed ants until the entire colony dies from lack of food from the foragers. Several of the most effective products for control of carpenter ants are available for use by licensed professional pest control operators.
To prevent carpenter ant invasions from outdoors, spray foundation wall, adjacent soil, and around doors and windows with one of the insecticides listed above. Leaking roofs, gutters, water pipes, or other sources of moisture coming into contact with wood create conditions attractive to carpenter ants. Elimination of these conditions greatly reduces the threat of these ants.
Openings in living trees attract carpenter ants. Close such openings. Stacks of firewood or other lumber outdoors are also attractive. The longer they are undisturbed, the better for the ants. It is better to keep on hand only the amount of firewood that you plan to use during one heating season. Store the wood off the ground and away from the house. Spraying firewood to protect it is of doubtful value and is not recommended.
INTERESTING FACTS: Ants of the genus Camponotus are known as carpenter ants because they house their colonies in galleries they excavate in wood. Carpenter ants do not eat the wood they remove during their nest-building activities, but deposit it outside entrances to the colony in small piles. The wood is used solely as a nesting site. The galleries of carpenter ants are kept smooth and clean, and are not lined with moist soil as termite galleries are.