In their natural environment, carpenter ants nest in dead trees and other dead wood. This enhances decay, which has ecological benefits. However, the ant achieves pest status when a colony invades the wood of a house or other structure, damaging its structural integrity.
Since they favor moist wood as a habitat, any condition that promotes moisture should be eliminated to prevent infestation. The easiest of these is keeping gutters clear so water does not run down the side of the structure or gain entry. Moist wood is much easier to chew. The ants do not eat the wood, but remove it to create galleries for their activities. The galleries run parallel to the grain, as they are created in the softer, nonlignin portions of the timber. The galleries have a sandpaper-like feel, due to fecal remnants, but the mud tubes produced by termites will not be present
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