Ants belonging to the Tetramorium genus are commonly known as “pavement ants,” and several Tetramorium species have spread throughout the world where they thrive in a variety of different habitats, including indoor environments. Multiple pavement ant species are household pests that have established non-native habitats that are largely limited to urban and suburban environments. Most pest control professionals and urban entomologists agree that T. caespitum is one of the three most commonly encountered, and commonly controlled ant pest species within homes and buildings throughout the United States.

caespitum workers are ubiquitous in most US states where they are readily found skittering across sidewalks, driveways, cement foundations, concrete slabs and other paved surfaces. Due to this species’ association with pavement, it’s simply referred to as the “pavement ant,” and workers frequently establish indoor nesting sites within wall voids, beneath floorboards, and in wall insulation. Although the pavement ant is the most abundant Tetramorium ant pest species in the United States, its close relative, Tetramorium bicarinatum, is more abundant on a global scale. T. bicarinatum is commonly known as the “bicolored pavement ant,” and this species is a very common ant pest of homes throughout the southeast.

The bicolored pavement ant inhabits only urban and suburban areas of Louisiana, and workers often nest within rotting wood, plant stems, beneath tree bark, and in soil beneath objects like rocks, landscaping ornaments, mulch, and flower beds. They also tend to nest along foundations in order to regularly enter homes to seek out foods, such as meats, grease, vegetables, fruits and sweets. However, workers are also known for nesting within pantries, flower pots and hard-to-access indoor areas like wall voids and behind kitchen cupboards. Foraging workers are 2 to 4 mm long, and they can be recognized for their reddish-brown colored head, midsection, and black abdomen. Given their sweet tooth, these ants are well controlled with sweet liquid baits, and a minimal amount of insecticide should be applied to wall cracks where workers travel through on their way back to the nest. Insecticide dusts can be injected into wall voids to eliminate nesting individuals, and a wettable insecticide powder can be applied around the perimeter of a home to prevent repeat invasions.

Have you ever witnessed ants emerging from wall cracks or narrow gaps around light fixtures within your home?