What is frass?
Carpenter ant frass is the waste the ants produce from their wood-excavating activities. The sawdust-like material contains fragments of chewed wood as well as feces, small pieces of soil and gravel, and parts of dead ants. Carpenter ants usually pile frass near nest sites.
What does frass look like?
Primarily consisting of wood chewings, carpenter ant frass looks like soft, fibrous bits of wood loosely compacted together. The crumbly material will be the color of the nearby wood being excavated and is usually arranged into a cone-like pile.
Can be mistaken for termite frass
Frass produced by carpenter ants may be mistaken for drywood termite frass. Close inspection is usually needed to tell the difference between the two. Drywood termite frass consists solely of fecal matter, whereas carpenter ant frass includes wood chewings and insect parts.
Signs of a Carpenter Ant Infestation
Frass piles that appear near slit-like openings in wood usually indicate carpenter ant infestation. These slits, also referred to as windows, are used as garbage chutes for frass. Windows appear smooth and oblong. Burrowed wood usually has multiple windows on the surface. Frass and windows are often the only external indicators of a carpenter ant attack.
Common spots where carpenter ant windows may be found include basements, attics, foundation walls, and porches. Moist wood provides an ideal environment for carpenter ants to nest. Many times wooden structures often make preferred nesting sites for carpenter ants.