Technical Papers

Homeowner's Guide to Odorous House Ants in New Jersey

Thursday, March 12th, 2015 by Bill Cowley

There are more than 700 species of ants in the United States. One of the more common species, the Tapinoma Sessile, is a native ant that can be found across the United States. The Tapinoma Sessile is better known as the Odorous House Ant. It received its common name because of the intense, rotten coconut-like smell it emits when crushed.

The Basic Characteristic of Odorous House Ants:

Odorous House Ants are relatively small, dark brown ants. They range in size from 1/16 to odorous house ant1/8 of an inch long. Like many other ants, Odorous House Ants have oval shaped bodies, a constricted waist, and a head that is larger than their middle section. Protruding from their head are antennae that help the ant to smell, touch, taste, and hear. All six of the ant’s legs are attached to their middle section, which is commonly known as the thorax. Unlike many other types of ants, the Odorous House Ant does not have a stinger in the last section of its body.

Odorous House Ants needed to find another way to protect themselves from predators and other ants that are vying for the same food because they do not have a stinger. In order to defend themselves, or their colonies, ants will scatter erratically and emit a foul odor from their anal sacs. Although humans are not threatened by the odor, small insects like other ants, are very disturbed by the smell.

How the Odorous House Ant Colony Works:

Unlike some other social insects, the Odorous House Ant may have a colony that contains more than one queen. Typically when the Odorous House Ant has a smaller colony (fewer than 100 workers) there will be only one queen. However, if the colony is larger there can be many queens. Typically the ant’s colonies will range from fewer than 100 workers to more than 10,000 workers. If the colony is large enough to have 10,000 workers there may be hundreds of queens. Although Odorous House Ants can develop extremely large colonies they tend to maintain colonies of only several thousand workers.

New Odorous House Ant colonies are formed primarily by budding. Budding is when one or more queens, along with some of the workers, leaves the main colony and moves to a new location. Because the colony reproduces by budding, their nests are not as permanent as some other types of ants, and therefore if conditions become unfavorable the ants will simply move to a new location. This behavior makes it more difficult to find and eliminate a nest.

The Diet of the Odorous House Ant:

Odorous House Ants are most attracted to sweet smelling substances, however, they will eat other food as well. In the wild, their primary source of nourishment is honeydew. Honeydew is a sweet smelling liquid secreted by tiny animals called aphids. The Odorous House Ant is so enamored with sweet tasting liquid that they have been known to protect a species of butterfly caterpillars from potential predators in order to drink the sweet liquid that the caterpillar produces. When the ants are near humans they will substitute the honeydew with a variety of different sugary substances like juice or soda. Odorous House Ants are also attracted to grease. This intense desire for sweet foods and grease is one of the main reasons Odorous House Ants enter peoples’ homes and are usually found foraging in the kitchen.

Why Odorous House Ants Infest Homes:

Odorous House Ants are often found outside the home, but sometimes the lure of food and a moist environment to build their colony will draw them into a house. Odorous House Ants need a moist environment in order to thrive. If a home has a moisture problem ants are more likely to stay in the home to make their nest. Moisture problems can come from a variety of issues but some of the most common are leaky pipes, damaged appliances, and improper ventilation systems. When ants do make their nests in homes they are often found near the moisture sources in places such as in wall voids near hot water pipers, in heaters, under sinks, in dishwashers, and beneath leaky fixtures. Another area that ants are frequently found is inside wood damaged by termites.

How Odorous House Ants Enter a Home:

The range of the Odorous House Ant is rather large; it can be found throughout the United States as well as in Canada and Mexico. The ant’s wide range is in part due to their ability to nest outdoors as well as indoors. Like most pests, ants can enter the home through cracks and holes as well as when doors are left open. Since Odorous House Ants are relatively tiny, they are able to enter through cracks that are extremely small.

How an Odorous House Ant Infestations Can Be Prevented:

Odorous House Ants are most commonly found outside but will come inside if the environment is hospitable. When they are outside they make their nests in a variety of areas including mulch, leaf litter, and in potted plant soil. They may also be found on trees, bushes, and shrubs while they are searching out places to find honeydew.

Keeping common nesting and foraging areas away from the home is an essential prevention tip. It is important to investigate the perimeter of the house to see if there are any trees or bushes touching walls or windows. Branches are often used by Odorous House Ants as bridges from the outside world into homes; if there is any plant material touching the exterior walls of the house, it should be cut back.

Mulch is a common area for the ants to build their colonies. If they are nesting next to the house, there is a good chance that they will enter the house to forage for food. In order to decrease the chance of the ants coming into the home, rocks or cedar mulch should be used instead of regular wood mulch.

The exterior of the home should also be checked for cracks and holes through which the ant can enter. If cracks or holes are found, it is important to seal them with caulk. Since Odorous House Ants are very small it is likely that there are holes in a home’s exterior wall that, while large enough to be used as an entranceway for ants, are too small for a person to detect. In that case, the best method of prevention is to make the home as least hospitable as possible. Leaky pipes and appliances should be fixed. All food, both sweet and savory, should be stored in tightly fitting containers. Any crumbs or spilled liquids should be cleaned immediately. Lastly, all food based trash should be put into a trash can with a lid and that trash should be removed from the house on a regular basis.

Take a look at this huge ant trail on this video from a recent client in Wall, NJ.