Maine is carpenter ant country. The state's forests, wet springs and wood-framed homes give these big black ants an ideal habitat, and Portland, with its Victorian porches, aging clapboard and salt-laden air, is no exception. Add pavement ants working under brick sidewalks and odorous house ants in kitchens, and you get a city where ant questions come up every spring.
PestMinistry is a referral service. We connect callers with independent, licensed ant control providers in our network and do not perform treatments.
Sorting out the ants
- Carpenter ants: the largest, often a quarter to half an inch or more, black or black with reddish tones. They nest in wet or decayed wood, and some also use foam insulation and hollow doors.
- Pavement ants: small, dark brown to black, nesting under pavers, sidewalks and slabs. You may see little piles of sand along cracks.
- Odorous house ants: small brown ants with a rotten-coconut scent when crushed, drawn to sweets and moisture.
- Acrobat ants: small, heart-shaped abdomens that they raise when disturbed, sometimes living in damp siding and foam insulation.
Salt air, rain and rotted wood
Coastal moisture is hard on wood. Window sills facing the harbor, porch rails, fascia boards and trim that stay damp from sea fog slowly soften, and that is where carpenter ant colonies begin. Neighborhoods such as the West End, the East End and Munjoy Hill have many older wood buildings with layers of paint hiding trouble spots. Look for frass, the pale sawdust-like debris ejected from galleries, along baseboards, window wells or under porch ceilings.
Correct treatment follows correct identification
- A technician follows ant trails at dusk or early morning, when carpenter ants are active, and searches for moisture-damaged wood.
- Satellite and parent nests are located. Sometimes treatment means opening a wall void, applying a dust or foam and repairing the leak.
- For sugar ants, baits are placed along trails so workers carry them back.
- Perimeter applications may be added outdoors, especially around foundations and trees touching the roof.
Spraying visible ants with household products usually only kills the foragers and leaves the colony intact.
Prevention tips for Portland homes
- Fix any roof, flashing or gutter leak immediately.
- Replace rotted wood rather than painting over it.
- Cut tree limbs and shrubs that bridge to the roof or siding.
- Store firewood outside and raised, and bring in only what you will burn that day.
- Seal gaps where utilities enter the house.
- Clean up sticky spills, and rinse recycling containers.
Ant seasons in Portland
Swarmers appear in late spring, often indoors on warm days, which signals a mature colony. Foraging peaks through summer evenings. In fall, ants may head indoors as temperatures drop, and any sighting in winter points to a nest in the heated part of the house, often near plumbing or a chimney.
Talk to a pro
For help, call (844) 725-1661. We will connect you with an independent licensed provider serving Portland.
Frequently asked questions
Do carpenter ants eat the wood?
No, they chew it out to create galleries, then push out the debris. They feed on sweets, insects and honeydew.
Is a single large ant indoors a problem?
One in spring may be a forager that wandered in, but repeated sightings, especially at night, suggest a nest.
Can ants damage my house as badly as termites?
Typically more slowly, but a long-established colony in wet wood can weaken structural members.
What is the best time to treat ants in Portland?
Late spring and summer are common, but a provider can treat any time when activity is found.