Ant season in Spokane starts when the snow melts and soil warms. Carpenter ants are the standout concern, largely because Spokane sits at the edge of ponderosa pine forest and many neighborhoods have mature trees, wooden decks and older wood-frame houses. Smaller ants, meanwhile, move into kitchens looking for sweet and greasy food.
The ants in your yard
Carpenter ants are the big black ants, sometimes with a red thorax, that nest in damp or decaying wood. Spokane's pine forests, fallen logs and old stumps are natural habitat, and when a colony expands, it sends satellite nests into houses. Pavement ants nest under concrete, sidewalks and driveways and push soil up through cracks. Odorous house ants emit a coconut-like smell and trail along counters, especially in spring and summer. Western thatching ants build large mounds of pine needles and twigs in forested areas and at the edge of yards on the North Side and in the foothills. They bite, sometimes painfully, but rarely enter homes in numbers. Moisture ants, yellowish and smelling of citronella, infest damp wood.
What draws them to a Spokane house
Moisture is key. Snowmelt, ice dams on roofs, clogged gutters and leaking window wells soak wood trim, fascia and siding. Decks attached directly to the house hold water at the ledger board. Trees touching the roof and firewood stored against the siding offer both shelter and a bridge. Older homes in Browne's Addition, the South Hill and Rockwood have original wood windows, which can rot over time, creating ideal nesting sites. Shade and pine needles in yards keep soil damp.
Indicators of an active nest
- Large black ants seen at night in kitchens or bathrooms, particularly in spring.
- Fine, sawdust-like debris with ant body parts below a wall, window or beam.
- A faint rustling in walls when the house is quiet.
- Winged ants appearing indoors in late spring.
- Foraging lines leading from a tree or log toward the house.
How providers handle it
For carpenter ants, the aim is to locate both the parent nest outdoors and any satellites inside. Technicians follow trails, tap along walls, and use moisture meters and sometimes thermal tools to find hollow galleries. Treatment may include baits, dusts into wall voids and exterior barriers around the foundation, windows and eaves. For small kitchen ants, baits and sealing do most of the work. Damaged wood should be repaired or replaced, and moisture sources fixed, otherwise the colony may return.
Reducing the odds
- Cut back tree limbs and shrubs touching the house.
- Keep firewood on a raised rack away from the foundation.
- Repair leaking gutters and roof flashing, and clear ice dams promptly.
- Seal gaps where wires, hoses and pipes enter the walls.
- Remove old stumps and dead trees near the home.
Where to start
If ants are showing up in numbers, call (844) 725-1661. PestMinistry is a referral service. We connect Spokane residents with independent licensed pest control providers who handle identification and treatment.
Do carpenter ants eat wood?
No, they excavate it for nesting and feed on sweets and insects, but the tunnels can still weaken structures.
Why do I see big ants in winter?
A nest inside a heated wall can stay active, which is a reason to investigate.
Are mound ants in my yard harmful?
Thatching ants can bite, and their mounds are unsightly, but they seldom damage buildings.
Will treating the kitchen trail end the problem?
For small ants, often yes. For carpenter ants, you need to find the nest.