General Information

Odorous House Ant Information Sheet

Odorous House Ant (Tapinoma sessile) Description of Workers: Small workers, around 1/16-inch to 1/8-inch (2-3 mm); dark brown to black. Bitter odor when crushed – said to smell like rotten coconuts.

Most common structure-invading ant in Washington and Oregon. They nest in a wide variety of places outdoors and inside. These ants are known for constructing shallow nests in soil underneath objects, such as stones, patio blocks and debris outdoors in the warmer regions of the US. Inside, they prefer areas with moisture such as around hot water pipes, heaters and most wall voids of any structure. Odorous house ants have multiple queens in each colony and the colony can number as many as 600,000 ants. The ants forage for food in all types of weather and temperatures down to 50 degrees Fahrenheit.

HABITS: A scout ant in search of food leaves the nest and, in the random search pattern that follows, takes a somewhat meandering path outward, until she finds food. She then feeds on the food source and heads straight back to the nest ( Figure 1). Somehow on the outgoing trip she can keep track of her position with respect to her nest, and, on the return trip, uses this information to take the shorter, more direct route home. On the way back to the nest, she lays down an odor trail. Once back in the nest, this scout ant then alerts her nest mates of the food find, which encourages them to leave the nest. These recruited ants will follow the odor trail directly to the food source. In turn, each ant will reinforce the odor trail until the food is gone. This behavior is a highly efficient means of exploiting a temporary food resource.

Figure 1. Ant trail.

Think of the way you take to the nearest fast food place that you may frequent. This is no different then you taking a walk or a drive to get food. You know the route to take.
In some instances, these odor trails can become more or less permanent, as in the case of ants that are visiting permanent food sources such as an aphid colony, garbage area, and other sites in structures with permanent food and water. The trail can even be physically cut into the turf, as with carpenter ants that chew their way through the thatch layer. This is not much different then us making a road or a freeway from one town to another. It is well known and easily traveled.

Recommendations to make sure treatment is successful

  1. Keep all alternative food sources to a minimum by not leaving food out on the counter, cleaning up after each meal, keeping kid spills cleaned up, and trashcans emptied. The more food products that are around your home the more attractive it is to the ants. The treatment that was done in home will work, but it will work faster if there is no competing food for the colony.
  2. Keep vegetation cut back so it does not touch the house. These ants will travel outside during warmer weather to eat the honeydew from plant insects and they will travel across the branches that touch the structure instead of traveling through the perimeter treatment we have applied.
  3. Keep all water spills cleaned up and water areas dry. These ants need a large amount of water to stay alive, less water the faster the colony will expire.
  4. DO NOT SPRAY THE ANTS IF YOU SEE THEM, THE CHEMICALS WILL MAKE YOUR ANT INFESTATION INCREASE AND SPREAD THROUGHOUT YOUR HOME AND POSSIBLY CAUSE THE TREATMENT THAT YOU HAVE SPENT YOUR HARD EARNED MONEY ON TO BE COMPLETELY USELESS.

As long as the above items are maintained, we will retreat your home for free as many times as needed to eliminate the ant infestation under your guarantee. 100% treatment satisfaction is my personal goal. SR.

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