Little black ants

What little black ants look like

Little black ants are among the smallest ants you will see indoors, at roughly 1.5 mm, and they are uniformly shiny jet black. The thing that gives them away is the trail. They form long, thin, unbroken lines that hug the baseboards, the edge of a counter, a pipe run or a wiring chase, often crossing a whole room in a straight line. Under magnification the waist has two nodes and the antennae end in a club of three segments. Workers are all one size, the body is smooth with no spines, and crushing one gives off no distinct smell. That lack of odour separates them from odorous house ants, which smell of coconut, and the neat trail separates them from crazy ants, which never walk in a tidy line.

Signs you have little black ants

• Baseboard trails. Thin dark lines of ants running along the bottom of a wall, under cabinet kick plates or behind a stove.
• Very small ants in numbers. Individually they are easy to miss, so people usually notice the line rather than a single ant.
• Kitchen and pantry hits. They are found in cereal boxes, sugar, crumbs, grease spots and pet food.
• Trails from an outlet or crack. The line often disappears into a gap at an electrical box, a window frame or a crack in a slab.
• Small soil piles outdoors. Fine craters of excavated soil in driveway cracks, along walkway edges and in garden beds close to the house.

Why little black ants come indoors

Outdoors they nest in soil, under stones, in rotting wood and in cracks in masonry and pavement. They are generalists and will eat sweets, grease, meat and other insects, so almost any kitchen is worth their time. They come in through the smallest openings, which is where their size works in their favour. Colonies have more than one queen and will nest indoors in wall voids, behind baseboards, under floor coverings and inside hollow doors, particularly where it is warm and slightly damp. A trail that stays busy overnight and through cold weather usually means part of the colony is already living inside rather than commuting from the yard.

How to keep little black ants out

• Caulk cracks in the foundation, slab edges, brick joints and around window and door frames.
• Fit or repair door sweeps and weatherstripping, since a gap the width of a business card is plenty.
• Store dry food in sealed hard containers rather than the original boxes and bags.
• Sweep and wipe under appliances and inside cabinets, where crumbs and grease collect out of sight.
• Keep mulch, planters and stacked wood off the foundation and repair damp or rotting trim promptly.

How GO! Pest Control treats little black ants

• Inspection. We trace the trail to where it enters the room and then to the nest, checking baseboards, outlets, cabinets, the foundation and any paved areas nearby.
• Treatment. We place sweet and protein baits along the working trails so foragers carry the material back to the queens, and we treat entry points and the exterior perimeter as needed.
• Follow-up. We return to confirm the trails have stopped and to re-bait or shift placements if new lines appear elsewhere in the building.
• Advice. We point out the specific entry points, storage habits and damp spots that keep drawing them in.

We are licensed, insured and bonded, and we work in homes, apartments, condos and businesses across the Toronto GTA, Ottawa and Hamilton.

Common questions about little black ants