Carpenter ants are found throughout North America.  These large black ants are called Carpenter Ants because they live in wood.  Unlike termites, carpenter ants do not eat wood.  Carpenter ants are predators that feed mainly on small insects like aphids and inchworms.  In temperate regions carpenter ant colonies hibernate in a state called “diapause” during the colder months.  As seasonal temperatures decline, carpenter ants produce an alcohol called Glycerol that prevents ice crystals from forming within their bodies. Shortly after the first frost, colonies gather together in the nest area in a tight group, with the queen ant in the center of the cluster.  Once “asleep”, the colony does not feed or drink until spring.  Utilizing fats stored within their bodies during the fall, the minimal requirements for winter survival are met.  With stable winter temperatures, the  carpenter ant colony will remain in this dormant state.

Nest locations vary greatly.  Dead trees, hollow spaces in living trees, logs, and stumps are places where  carpenter ants will make nests.  Some nests have galleries(chambers and tunnels) that extend far below the surface of the soil.  Carpenter ants also make nests in homes, sometimes causing extensive local damage.  Most nests begin in an area of decaying wood that gets wet.

Queen ants will chew off their wings after mating and search out a suitable place to start a colony.  The small initial chamber will hold the first eggs and minor workers who begin to form the new colony.  When a colony is first starting there are very few, small workers. Over time, if things go well, the colony will find a suitable nest site and begin work on the nest.  It takes carpenter ant colonies from 3-6 years to reach reproductive maturity.  Mature colonies will swarm once or twice a year in warm weather, releasing the reproductive’s.  Carpenter ant colonies can live for more than 15 years.  Most mature nests will have more than 2500 ants.  Large, successful colonies can have huge numbers of ants.  As the colony grows, different castes of workers are produced, along with future queens and smaller, wasp-like males.  The reproductive forms do not benefit the colony itself but leave the nest and continue the species.  Large winged females  may be seen flying at night, attracted to lights or walking along the ground searching for mates and places to hide and form a nest.  Wandering queen ants may be found in homes and most will die or become food.  Most insectivores will eat winged carpenter ants on sight.

When spring comes, days lengthen and temperatures climb. The nest begins to stir.  Winter has been long and fat stores are all but gone.  Inside the nest ants are beginning to move about and stretch their legs.  There is no food outside yet as temperatures are still low, buds and leaves are still forming.  One thing carpenter ants will need when they first wake up is water.  Carpenter ants get most of  their water from the food they bring back to the larvae.  Larval ants digest the food brought to them and secrete a nutritious fluid to the adult ants.  There may be few larvae present in spring, the queen ant has not been laying eggs over the winter but will start soon, in order to feed the colony.  With no wild food sources available, carpenter ant workers will come out and search for water.   They may also locate sweets, pet food, along with some fruits and vegetable material that is damp.  Workers may also be interested in house plants that are infested with aphids, scale insects, or whiteflies.  These insects secrete honeydew that carpenter ant workers can readily consume, as well as bring back to the nest.

One of the first signs that carpenter ants have moved into a structure is the presence of worker ants in spring, before leaves have formed on the trees.    The first warm days will wake the ant colony up, and they will remain active until the next fall, although cool nights will reduce activity.  Because food is scarce, the first workers usually find water sources like dishwashers, sinks, showers, and pet water. Once scouts find a water source, pheromone trails are laid down that guide other ants to the water.  The ant trail may lead directly back to the nest area or give clues to it’s location.   Ants on walls this time of year may indicate a wall void nest.  Ants in a location not near a water source may be near a nest site.  Ants will travel along these trails one after the other, collecting water with their mouth parts and storing it in their abdomen.   Carpenter ants returning to the nest will be larger than ants leaving.

With ever warmer days, leaves form on tress and shrubs. When daytime temperatures climb sufficiently, ants will begin to venture outside of the nest.  The insects that live outside on trees and shrubs start their activities, and the ant colony begins foraging outside.   Carpenter ant workers may be seen leaving the structure on branches, wires, around foundation corners, and edges.  Doing much of the foraging at night, a large colony will have workers coming and going during the daylight hours as well.  Workers can be seen carrying small inch worms and other prey into the colony.  Ants carrying prey into a house usually means that there is a nest inside.

The busy workers do all the labor in the colony with the exception of egg laying.  The queen lays the eggs, which hatch into little “pope-like” larvae. The larvae go on to form pupae that become the adult ants.  If the colony has reached maturity, a swarm may take place. This swarming is indicated by  large numbers of winged ants either inside or on a structure.  Swarming takes place in warm temperatures, and my take place several times if the colony is large.  Swarming also takes place outside, and if conditions are right, many colonies may swarm at the same time.  This  mass swarming behavior allows males and females from different colonies to exchange genetic material.  Great numbers of swarmers may be produced, most will not survive the first month, less the first year.  Competition for nest sites and feeding territory is fierce.  Rival carpenter ant colonies will fight for feeding rights, eating the enemy workers and taking the eggs, larvae, and pupae as food.  Some ant species even take slaves.  Large colonies may have several satellite nests where pupae are taken to develop, like in the sunny side of  a house or the warm attic.

Control of carpenter ants is best left to the Pros.   Do It Yourself treatments can be dangerous and frustrating. With the right training and material, Pest Control Professionals have what it takes to remove carpenter ants.  If you begin to see ants inside this spring it is likely that you have an ant nest in the house.  Why wait until carpenter ants are everywhere, potentially causing damage?  Don’t hesitate, call a Pest Control Professional as soon as you notice carpenter ant activity.