Fact vs. Fiction: Odorous House Ants

The nesting sites for the odorous house ant (OHA) usually are determined by proximity to moisture and heat; they love standing water and leaky pipes. Photo courtesy of, and copyrighted by, Gene White, pmimages@earthlink.net

Fiction: Odorous house ants (OHA) or Tapinoma sessile, are easy to kill.

Fact: OHA can be managed with customary professional ant control products and techniques. The sooner they’re identified and interventions are put in place, the easier the process. Individually, these insects are tough. Crushed females have been known to still lay eggs and survive for as long as two months without food or water. Injured workers have been known to continue living and working, even while missing body parts.

Fiction: OHA are only attracted to sugar.

Fact: The sweet tooth of OHA is well documented, but they feed on various food sources, including other insects. Nesting sites usually are determined by proximity to moisture and heat. OHA love standing water and leaky pipes. In dry, indoor conditions, they’re often found in houseplants and under toilet lids. Outdoors, they’re commonly found under rocks, bricks and in exposed soil and firewood stacks.

Fiction: OHA are aggressive and keep tight little colonies.

Fact: OHA tend to overwinter in one nest. However, come spring, the colony branches out with multiple queens and locations. It’s not unusual to find them sharing nesting areas with other ant species.

Fiction: Spraying is the best way to control OHA.

Fact: Residual sprays and aggressive sanitation can stress colonies and prompt OHA to scatter. First, use slow-acting bait matched to their current food preferences — sugar, fat or protein — and remove all competitive food sources. Allow time for the active ingredient to work its way through the colony before implementing residual or cultural controls.

You can reach the Kate and Jeff McGovern at jeffreymcgovern@mindspring.com.