PEST PREVENTION FIELD GUIDE

Ants in the home: find the cause, not just the trail

Ant trails often connect a nest to accessible food or water. Their exact species matters, especially when large ants appear near wet wood.

What to do first

1. Follow the trail from a distance to locate gaps, crumbs, drips or pet-food bowls.
2. Remove crumbs and sticky residue, wash surfaces, and keep pantry supplies tightly sealed.
3. Repair moisture problems and seal small openings after activity decreases.

What to avoid

Avoid improvised pesticide sprays and using chemical products near food. Disturbing an unknown nest can worsen the problem.

When to get expert help

A recurring trail, ants emerging from a wall, or suspected carpenter ants near damaged wood warrant professional identification.

Further guidance

Read Health Canada's pest-control tips and check local public-health recommendations. If a pesticide is considered in Canada, choose a product with a PCP registration number authorized for the pest and application site and follow its label precisely.

Educational information only, not a species diagnosis or professional inspection. Updated October 11, 2026.