Pests
Carpenter ants
Carpenter ants are large dark insects that nest in damp or moisture-compromised wood. Unlike termites, they do not eat the wood of trees, stumps or buildings.
University of Maryland Extension calls carpenter ants large dark insects that can sometimes become a problem in the home. They cause damage by building nests in damp or moisture-compromised wood. Once a nest is established in damp wood, the ants may extend galleries into sound, dry wood.
The same source says carpenter ants do not actually consume the wood of trees, stumps, or structures, but they do use it for nesting. That sets them apart from the subterranean termite, which feeds on wood. A decaying stump is one kind of wood where nests can occur. Ants inside a building are a pest-control question, not a stump question.