- Size: 1/8 to 1/2 inch long; workers vary in size.
- Color: commonly black but some species are red and black, solid red, or brown.
- One node between the thorax and abdomen.
- Winged reproductive males and female; wingless workers.
Habits of Carpenter Ants:
- Eastern U.S. – mature colonies with 10-15,000 workers including satellite nests.
- Western U.S.- mature colonies with 10-100,000 workers.
- Developmental time (egg to adult): about 60 days.
- Swarm: May through August (in the east); February through June (in the west).
- Social insects that usually nest in wood.
- Excavate galleries and tunnels in rotting and sound trees; within structures, readily infest wood, foam insulation, and cavities.
- Often found in conjunction with moisture problems.
- Feed on sweets liquids, honey dew from insects such as aphids, live or dead insects, and meat.
- Do not eat wood.
- Feed from late evening through the early morning.
- Foraging trails extend up to 300 feet.
- Enter homes through gaps and cracks.
- Large numbers of winged adults within a home indicates that the nest(s) exists indoors.
- Workers push frass (wood shavings and pieces of foam insulation) out of the nest through slit-like openings in the surface.
- Frass may contain fragments of other insects.
- Nest in trees weakened by decay.
Damage Caused by Carpenter Ants:
- Excavate moisture-damaged wood.
- Occasionally damage sound wood within structures.
- Large colonies can cause substantial structural damage.
- Structural moisture problems, e.g., roof, soffits, bathroom, and kitchen areas.
- Rustling sounds in wall voids.
- Frass containing insect fragments.
- Foraging ants, especially in the evening.
How to Control and Kill Carpenter Ants:
- Moisture problems should be eliminated by drying out the wood.
- Overhanging tree limbs which touch the structure, stumps, and firewood should be removed.
- Cracks and crevices should be sealed to prevent entry.
- The source of the ants, i.e., the nest and satellite nests, should be located.
- Nests should be treated with a residual spray or dust.
- Nests in voids should be treated by drilling holes in hollow doors, wall voids, ceiling voids, veneers, etc.
- Infested wood should be drilled and a dust or liquid formulation should be applied directly into the galleries.
- Treating worker trails reduces the infestation, but does not eliminate it.
- Outdoor infestations can be reduced by the application of barrier treatments.
- Baits are effective and can be used to eliminate the colony.