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A CASE OF MISTAKEN IDENTITY: Carpenter ants are sometimes confused with termites. While termites are white in color and smaller than a grain of rice, carpenter ants look like regular black ants except a little bigger. Adult carpenter ants grow to be as much as one-half inch long, and queens are often twice that size. If you get really intimate with a carpenter ant you will notice that they have bent or

"elbowed" antennae. They only have one

node or bump on the joint between the

thorax and the abdomen (the thorax is the

middle section and the abdomen is the rear

one. Also, the thorax on some carpenter

ants is burnt orange or chestnut red in color.

Carpenter ants also have hairy abdomens.

You will never see a termite unless you

break open a piece of infested wood or a

shelter tube (tunnels that termites use to

get from the soil where they live to the

wood they are eating). Carpenter ants, on the other hand, roam around looking for food the same way ordinary ants do. Termites eat wood, but carpenter ants do not. Instead, carpenter ants burrow into wood to make a nest and they push the wood and other debris (called frass) out of their colonies. The inside of the infested wood is spotlessly clean and consists of smooth galleries through the wood. Now that we've cleared that up, let's move on to more information about carpenter ants.

FINDING A HOME: Most nests are outdoors in tree stumps, fence posts, and porches. However, carpenter ants will also nest indoors in rotten or damp wood or in solid wood that is adjacent to a source of moisture such as a sweaty pipe, near washing machines, dishwashers or baseboards in damp areas. Although they normally excavate their colonies, they sometimes live in hollow doors, window frames, etc. Carpenter ants are omnivorous meaning they eat all different types of food. Outdoors they eat plants, insects, (their favorite are aphids), fruit, etc. Indoors they eat household foodstuff, especially syrup, honey, sugar, and meat fat or grease. On their way back to the colony they rarely take the same route, which can make it difficult to locate the nest. Even though the colony may be indoors, most of the ants will go outdoors to feed. This also reduces the likelihood of detection. To make matters worse, the ants are more active at night than in the daytime, and some colonies go dormant during the winter. (The colony is most active during the spring and summer.)

REPRODUCING AND COLONIZATION: In the summer months, swarms of winged carpenter ants (both male and female) leave the colony. They mate on the fly then return to earth and shed their wings. The queen finds a suitable place to lay her eggs which then hatch into larvae. The larvae develop into adults "worker ants" in 2 to 10 months depending on the temperature. A new colony will consist of one queen plus 10 to 20 workers. A colony takes 3 to 6 years to develop during which time the queen lays eggs and the workers care for the young. A queen has a life expectancy of 8 to 12 years while workers can live 4 or 5 years. When the colony has developed, winged males and females form. They remain in the colony over the winter and take flight the next summer to begin the process again. A well developed colony may contain thousands of ants. Needless to say, to support a colony of this size the damage to wooden components in a home can be significant.

KISSING YOUR ANTS GOODBYE: Locating the colony is necessary to get rid of the ants. This can be tricky. Sawdust at entrances to the colony is one method. Listening for the ants is another. At quiet times, a distinct dry rustling sound can be heard from the colony (some specialists use stethoscopes to listen for them). If you bang on the wood, it disturbs them and the noise level from the colony will increase. Locating the colony and eliminating it is best left to a pest control specialist. Your best defense against carpenter ants is elimination of damp environments and rotted wood within the home. Storing firewood adjacent to the house or in the basement is not wise. While chemical treatment can kill the colony, they'll be back next year if ideal conditions still exist.

Richard D. Malin & Associates: Technical Library

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