Ants
Big-Headed Ant
A small, light-brown ant whose larger workers have oversized heads. In Canada it is found mainly indoors — in heated buildings, greenhouses and potted plants.
Quick facts
- Size
- 2–4 mm
- Colour
- Light brown to reddish-brown
- Active season
- Year-round indoors
- Where found
- Greenhouses, heated buildings, potted plants, wall voids
How to Identify
- Two worker sizes: small workers and larger "majors" with very large heads
- Light brown to reddish-brown body
- Travels in trails along edges and baseboards
Signs to Look For
- Trails of small ants to food, especially proteins and grease
- Small piles of soil or debris near cracks and planters
- Ants coming from potted plants or floor drains
Why It Matters
- Contaminate food and food-prep areas
- Protect sap-feeding insects like aphids and scale, harming plants
- Colonies have many queens and can spread through a building
Prevention Tips
- Clean up food and grease spills promptly
- Inspect new plants before bringing them indoors
- Seal cracks around baseboards and plumbing
- Fix leaks and reduce moisture
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Pavement Ant
Small, dark brown ants that nest under sidewalks, driveways and slabs, and often trail indoors looking for food.
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