Identification
| Trait | Detail |
|---|---|
| Size | Workers about 2.5–3 mm—small but not “ghost” tiny. |
| Colour | Dark brown to black; legs often lighter. |
| Head/Thorax | Fine parallel grooves (striations) visible under magnification. |
| Nests | Small soil craters between pavers, along driveways, and under stones. |
| Swarmers | Winged reproductives appear in spring and early summer near sidewalks. |
| Similar ants | Odorous house ants and others share kitchens; trail speed and nest location help separate them. |
Pavement ants (Tetramorium immigrans complex in many urban Canadian contexts) are the crater-making ants along patio stones and garage slabs. Indoors they follow plumbing lines and baseboards to sweets on counters, pet bowls, and sticky spills. In Greater Vancouver’s wet winters, warmth and moisture near slab edges keep underground nests active near foundations.
Behaviour & Habits
Colonies live under hardscape: driveways, walks, and patio slabs where sand base provides tunnels. They recruit strongly to food sources, laying pheromone trails that look like busy highways overnight. Swarming events can coat windows and sliding doors briefly in spring, alarming homeowners even when long-term risk is low.
They are opportunistic nesters; expansion can follow disturbed soil during landscaping. They do not excavate structural wood like carpenter ants.
Health & Property Risks
⚠ Health risk — professional removal recommended. Pavement ants are primarily a nuisance contaminant risk in food zones rather than a wood-destroying pest.
Large indoor trails can cross food prep surfaces; individuals can carry bacteria picked up from refuse areas though everyday risk is moderate compared with filth flies. Property risks are cosmetic soil piles and occasional weak sand under pavers—not beam damage.
Prevention
- Seal slab cracks and expansion joints where trails enter.
- Wipe counters and floors; store sweets in sealed containers.
- Rinse recycling and organics bins that touch the house.
- Power-wash heavy trail lines to disrupt recruitment when safe for surfaces.
- Keep mulch shallow against foundations; avoid continuous soil above slab edge.
- Fix leaks that wet sand bases beside drives.
How We Treat Pavement Ants
We track trails to entry points, place baits or non-repellent approaches along routes per label, and treat exterior nest sites when accessible under stones or joints. Interior work focuses on kitchen and utility lines rather than random baseboard fogging. Follow-up verifies trail break and notes new slab work that might reopen routes.
For kitchen and hardscape-related ant work, review our ant control service in Greater Vancouver and schedule an inspection.
Frequently Asked Questions Q: Why suddenly thousands on my patio?
A: Swarming or strong recruitment to a food or moisture cue can spike numbers quickly.
Q: Are they biting?
A: They can nip if handled; stings are not a concern like wasps.
Q: Do I need to rip up pavers?
A: Rarely; targeted treatments and joint sealing often suffice.
Q: Will rain wash bait away?
A: Exterior applications account for weather; repeats may be scheduled.
Q: Can they live only indoors?
A: Uncommon; most lines trace to exterior slab or wall void moisture.
Q: Are they termites?
A: No—different insects; winged swarmers look different under inspection.
Professional Ant Control
Pavement Ant problems in Greater Vancouver require a systematic approach — inspection of the full property, elimination of the root cause, and documented follow-up. Our ant control service covers all of this.
View Ant Control