The carpenter ant is the largest ant in the Bay Area with the workers growing to about 1/4" long and the queens growing up to 3/4". This ant color varies from black to red and black.
A Carpenter ant's food sources consist of honeydew from aphids, other insects and plant juices but once in your house, they will forage for mainly water and food scraps. The colony begins with one fertile female. Nests are then created in deteriorated wood which has been exposed to moisture. A colony does not produce young queens or males until it's grown to the size of about 2,000 or more workers, which may take a colony anywhere between three to six years to reach this stage. Every year thereafter the colony will produce winged queens and males which venture off to start new colonies.
Carpenters will primarily live in rotting logs and stumps. However, they will make nests in places like the roof, window sills and wood that is in contact with the soil. Generally there will be one central nest and several satellite ones. Because they are one of the larger species of ant, they can travel long distances between nests and food sources.
One of the biggest misconceptions with Carpenter ants is that they eat wood. This is not true, instead they excavate the wood and pile it nearby, which is called frass. If you were to rummage through the frass you will find bug parts and other debris from the colony. Another misconceptions is that they can cause structural damage to buildings, which is rarely the case. The significant damage can come when an infestation goes untreated over a long period of time. Carpenter ant colonies can thrive for years at a time when unbothered.
Carpenter ant colonies can be controlled with an exterior and interior treatment. All areas containing the frass inside the house will receive a treatment to kill the satellite colony. Treating the exterior helps prevent others from entering.
For long term control every other month or quarterly service is recommended.