Odorous House Ant Control | PESTWISE

Learn more about Odorous House Ants and how PESTWISE can help eliminate these unwanted pests from your residential or commercial property. Our expert team is dedicated to providing safe and effective pest control solutions in Belleville, Ontario, Canada.

Odorous House Ant

Scientific Name: Tapinoma sessile

Identification: Odorous house ants are small ants (about 2.5–3 mm long) that are dark brown to black in color. Their most distinctive trait? When crushed, they emit a strong, rotten coconut-like odor.

They have an uneven-shaped thorax (seen from the side) and a single, hidden node between the thorax and abdomen — giving them a smooth body profile. Their movement is erratic and quick, often seen trailing in long lines toward sweet food sources.

Habitat: Odorous house ants nest both indoors and outdoors, often choosing areas near moisture or food sources.

Common Indoor Nest Sites:

  • Wall voids near hot water pipes

  • Beneath sinks or dishwashers

  • Inside window and door frames

  • Under carpets or behind baseboards

Common Outdoor Nest Sites:

  • Under mulch, logs, stones, or soil

  • Beneath pavement or concrete slabs

  • Along building foundations, especially where water accumulates

Odorous house ants are highly adaptable and may relocate frequently — especially after disturbance or weather shifts. Their nests are typically shallow and diffuse, and colonies can contain multiple queens.

Behavior: Odorous house ants are highly active, fast-moving ants that often form long, chaotic trails while foraging for food. They are especially attracted to sweet substances like syrup, juice, and fruit.

  • Erratic Movement: Unlike pavement ants, their trails often appear disorganized and rapid.

  • Indoor Invaders: They readily move indoors during rainy or cold weather to seek shelter and moisture.

  • Multiple Colonies: Colonies may contain multiple queens and frequently relocate their nests if disturbed.

  • Nocturnal Activity: Most active in the evening and overnight, often seen on kitchen counters, sinks, or pantry shelves.

  • Rotten Coconut Smell: When crushed, workers emit a distinctive foul odor, which is a key identifying trait.

Life Cycle: Odorous house ants undergo complete metamorphosis, progressing through four key stages:

  1. Egg – Tiny white eggs laid by multiple queens inside wall voids, baseboards, or under floors.

  2. Larva – Legless, white grubs fed by workers. Growth rate depends on warmth and food.

  3. Pupa – Immobile transitional stage, developing inside cocoon-like cases.

  4. Adult – Emerges as a worker, male, or queen. Colonies expand rapidly, often containing multiple queens.

Key Notes:

  • Life cycle takes 2–3 months in indoor conditions

  • Colonies grow through budding, not swarming

  • Persistent indoors year-round

Risks & Concerns: 

  • Food Contamination: Odorous house ants forage in unsanitary areas like sinks, trash bins, and bathrooms, then travel across food surfaces — increasing risk of contamination.

  • Rapid Nest Expansion: Colonies can grow rapidly and spread through walls, insulation, and flooring. Their tendency to relocate makes infestations harder to track.

  • Structural Entry Points: They can exploit tiny cracks in siding, windows, or foundations to enter homes and commercial kitchens.

  • Strong Smell When Crushed: Their characteristic rotten coconut odor may be unpleasant if infestations are widespread or crushed during cleaning.

  • Difficult to Eliminate with DIY Methods: Disturbing the colony or using sprays can cause ants to split into satellite nests, worsening the problem.

Risks & Concerns: 

  • Food Contamination: Odorous house ants forage in unsanitary areas like sinks, trash bins, and bathrooms, then travel across food surfaces — increasing risk of contamination.

  • Rapid Nest Expansion: Colonies can grow rapidly and spread through walls, insulation, and flooring. Their tendency to relocate makes infestations harder to track.

  • Structural Entry Points: They can exploit tiny cracks in siding, windows, or foundations to enter homes and commercial kitchens.

  • Strong Smell When Crushed: Their characteristic rotten coconut odor may be unpleasant if infestations are widespread or crushed during cleaning.

  • Difficult to Eliminate with DIY Methods: Disturbing the colony or using sprays can cause ants to split into satellite nests, worsening the problem.

Contact PESTWISE today for a free consultation and to schedule your Odorous House Ant treatment.

Don't let pesky ants invade your home or office. Trust PESTWISE to get rid of them quickly and effectively.