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Carpenter Ant

Camponotus pennsylvanicus · Ant

Scientific Name

Camponotus pennsylvanicus

Category

Ant

Size

1/4 to 1/2 inch workers, up to 1 inch queens

Color

Black (occasionally black and red)

Lifespan

6 to 10 years for queens, 1 year for workers

About the Carpenter Ant

The black carpenter ant is Michigan's largest and most destructive ant. Unlike termites, carpenter ants do not eat wood. They excavate galleries for nesting, producing smooth, sandpaper-finished tunnels and characteristic sawdust-like frass. A mature parent colony contains 10,000 to 20,000 workers plus satellite colonies.

Habits & Behavior

Carpenter ants nest in moist or damaged wood: window frames, door sills, eaves, wet roof decking, plumbing leaks, decks, porch posts, and fallen tree limbs. Parent colonies live outdoors in stumps and logs, while satellite colonies inside the home house workers, older larvae, and pupae. Foraging trails can extend 300 feet from the nest.

Signs of a Carpenter Ant Infestation

Sign #1

Piles of frass (wood shavings mixed with insect parts) below wall voids, window sills, basements

Sign #2

Winged reproductive swarmers indoors in spring (April to June) indicates mature indoor colony

Sign #3

Large (1/4 to 1/2 inch) black ants foraging in kitchens and bathrooms at night

Sign #4

Faint rustling sounds in walls during quiet nights

Sign #5

Damaged or hollow-sounding wood with smooth sandpaper-finished tunnels

Sign #6

Ants trailing along foundation walls, deck edges, or up tree trunks

Carpenter Ant Pressure in Michigan

Carpenter ants are endemic throughout Michigan. Luxury subdivisions with mature oak canopy, extensive mulched landscape beds, and elaborate deck structures have the heaviest pressure. Northville, Rochester Hills, Clarkston, Lake Orion, Commerce Township, and Hartland see the highest rates because of heavy forested and lakefront property.

How BTR Treats Carpenter Ant Infestations

BTR uses a perimeter plus interior program: (1) non-repellent transfer insecticide applied to foundation, eaves, and known trails, (2) bait placement at active trails, (3) direct treatment of identified nests. The non-repellent chemistry allows workers to carry active ingredient back to the colony, eliminating the queen. Most Metro Detroit carpenter ant jobs clear in 2 to 3 visits with 90-day warranty.

Prevention Tips

Fix all roof leaks, plumbing leaks, and poor drainage immediately. Trim tree branches at least 6 feet from the house. Remove stumps, dead trees, and woodpiles within 20 feet of the foundation. Store firewood off the ground and away from the house. Seal cracks in siding, soffits, and window frames.

Frequently Asked Questions About Carpenter Ants

How do I know if I have carpenter ants or termites?

Carpenter ants have bent antennae, pinched waists, and wings of unequal length. Termites have straight antennae, thick waists, and wings of equal length. Carpenter ants produce frass (wood shavings); termites produce no frass. Carpenter ant tunnels are smooth and clean; termite tunnels contain mud and soil.

Are carpenter ants as destructive as termites?

Carpenter ants cause structural damage over years, not months like termites. However, mature colonies with satellite nests can cause significant damage to wet wood, deck posts, window frames, and roof decking. Early treatment prevents long-term structural issues.

Why do I see carpenter ants only at night?

Carpenter ants are primarily nocturnal foragers. Peak activity is 10 pm to 4 am. Daytime sightings indicate a large mature colony with workers active around the clock, which usually means the nest is indoors.

What does spring carpenter ant swarming mean?

Winged carpenter ant swarmers appearing indoors in April, May, or June indicate a mature parent or satellite colony has been inside the home for at least 2 to 5 years. Swarming means new queens are dispersing to establish additional satellite colonies. Immediate treatment is recommended.

Does BTR treat carpenter ants outdoors?

Yes. Our carpenter ant program includes exterior perimeter treatment covering the foundation, eaves, known trails, mulched beds, and nearby tree trunks. Outdoor treatment eliminates foraging workers before they reach the home.

Carpenter Ant Problem? BTR Can Help Today

Free inspection. Licensed Michigan exterminators. 90-day warranty on most services.

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