Carpenter Ant Inspection

Because Carpenter Ants forage primarily at night, use a flashlight and conduct inspections in the evening or early morning to locate foraging trails and nest sites. Remember, workers have been known to travel as far as 100 yards from the colony to search for food and water. You may have a long way to go to find the nest of those Ants you found in your kitchen.

common carpenter ant areas A thorough inspection is important to find all the sites. Don't conclude your inspection when one colony is found; several colonies may be present in and around a single structure; both parent colonies and satellite colonies.

Parent colonies contain the egg-laying queen with its broods, as well as the worker ants. The satellite colony has mature larvae and pupae as well as workers. Inspect wooden structures associated with high moisture, where there may be water damage resulting in softened and moist wood. Carpenter Ants will inhabit wood structures that has already been damaged by water or insects.

Carpenter Ants prefer frames and sills of windows and doors, as well as tub enclosure walls, kitchen and bath plumbing walls, around sinks, chimneys, and in hollow spaces such as wall voids.

Common areas of carpenter ant problems in a house.

carpenter ant sawdust Sawdust debris discarded from the carpenter ants making their galleries

UNL extension publication
Photo: Barbara Ogg, UNL

To locate Carpenter Ant nest sites, focus on these areas

Indoors

  • Moisture problems
  • Wall voids
  • Attics (especially under roofing and insulation)
  • Flooring or sub-flooring
  • Ceilings
  • Windows
  • Skylights
  • Hollow doors
  • Dishwashers
  • Trash compactors
  • Plumbing, pipe chases (kitchen/bath)

Outdoors

  • Trees
  • Stumps/dead trees
  • Landscape timbers
  • Woodpiles and fences
  • Leaf litter
  • Debris piles
  • Mulch beds
  • Door kick plates
  • Roof lines and gutters
  • Soffits and vents
  • Windows and door frames
  • Utility entrances (electric, cable, TV, telephone, gas lines)
  • Sheds and doghouses
  • Trash containers

How To Detect Carpenter Ant Galleries

Frequently you can see what looks like sawdust near Carpenter Ant galleries. This sawdust, known as frass, is shredded fragments of wood that have been ejected from the galleries. This is a good indication that a nest is nearby.

If you suspect Carpenter Ants are present but there is no frass, use the handle of a screwdriver to tap along baseboards and other wood surfaces, listening for the hollow sound of damaged wood. If a nest is nearby, often the Carpenter Ants will respond by making a rustling sound within the nest, similar to the sound of crinkling cellophane. Use a screwdriver to probe the wood near a suspicious area; this may reveal excavated galleries.

carpenter ant damage

Notice how smooth the galleries appear.

carpenter ant damage Carpenter Ants clean and polish their nests and push out debris (shavings, frass) through holes.

Use a screwdriver to probe the wood near a suspicious area; this may reveal excavated galleries.