Homeowners in Massachusetts complain about nuisance ants within homes more often than any other household insect pest, including cockroaches, termites, bed bugs and flies. While medically significant ant species like red-imported fire ants and harvester ants are largely absent from the northeast, some of the most hard to manage ant pests frequently infest homes in the region. The most common species of ant pest found in Massachusetts homes include odorous house ants, black carpenter ants, and pavement ants. Ant species belonging to the Brachymyrmex genus, such as dark and brown rover ants, are very common pests of homes in the southern states, but only one species from this genus, B. depilis, is known to frequently infest homes in Massachusetts. These ants are notorious for being exceedingly hard to control within residential areas, and infestations in homes are often associated with potted plants and contaminated mulch purchased from stores.

Ants in the Brachymyrmex genus are more commonly known as “rover ants,” and despite the status of B. depilis as a common and widespread household pest, this species has not been given a common name, and their pest behaviors have not been well described. B. depilis is exceptionally small in size, as yellow-colored workers are less than 1/20 of an inch in body length, and they lack a stinger. These ants live in relatively small colonies that contain one queen and anywhere between a few hundreds to a few thousand workers. Colonies are located within the ground soil, often beneath objects like rocks, mulch, bundles of leaf litter, concrete slabs, and against foundation walls, but they are also capable of establishing nests within potted plants, wall-voids and other well concealed indoor harborages. B. depilis is highly vulnerable to dessication, making them dependent on high-moisture environments. Because of this, these ants are frequently found infesting floor voids and wall voids in bathrooms and kitchens where water from dishwashers, sinks and plumbing provide ideal living conditions. The small size of workers and their habit of nesting within seemingly improbable indoor locations make B. depilis infestations difficult to eliminate. However, gel baits have shown to effectively control these ant pests.

Have you ever suspected ant pests of being present within the wall voids in your home?