Carpenter ants

Carpenter ants are the common, large black ants (1/4 to 1" in length) that every one has seen. They nest in wood, but do not eat the wood for food the way termites do. They chew tunnels and galleries in wood(preferably moist or partially rotted) for a nest area, toss the wood chewing out of the nest sometimes resulting in a pile of sawdust. How destuctive they are will depend in large part on where they build their nest. If they nest in a wall stud, or window frame, they probably won't do any significant damage, but if they get into a carrying beam, a door sill, or foundation sill they can do significant structural damage. They are notoriously hard to treat unless the nest can be found which is not usually accomplished. They do not respond well to "Hardware store" ant traps or sprays, so it is usually a waste of money to even try. A professional should be called in, because they have the experience of knowing likely nesting areas. Carpenter ant prevention can be accomplished by:
1. Storing firewood off the ground and at least 100' from the house.
2. Correcting any moisture problems within the house such as leaking pipes or condensation problems.
3. Removing any broken, decaying, or dead trees or branches, and stumps within 100' of the house.