The ants people see crawling about on sidewalks in large numbers are most likely workers of the Tetramorium genus, or “pavement ants,” as they are commonly known. These moderately sized ants are around 3/16 of an inch in length and brown to dark brown in color. Pavement ants are one of the most common home-invading ant pests in the country, as a recent nationwide survey of pest control professionals found that pavement ants were the second most commonly managed ant pests within homes during 2016. Pavement ants are known to establish nests within wall voids, and they frequently infest kitchens and pantries where they consume and contaminate a variety of food sources, including sweets, meat, nuts, cheese, bread, pet food and grease.
While pavement ants are among the most abundant ants in the US, experts have been struggling for centuries to divide pavement ants into different species based on the physical appearance (morphology) of different collected specimens. However, pavement ant specimens are too similar looking to be divided into different species. Because of this, all pavement ants have been referred to by the species name T. caespitum, and the confusion concerning pavement ant taxonomy is known as the “T. caespitum complex.” A recent study using DNA technology found that a total of eight ant species have commonly been referred to as T. caespitum. One of these species, T. immigrans, is now understood to be the principle pavement ant pest species in the US, and they all originate from one single European population that arrived in the US during the early 19th century.
Pavement ants live in colonies that contain around 10,000 individual ants, and they swarm in large numbers during the summer months. Pavement ants are known for establishing nests along or within exterior foundation walls, which sometimes results in indoor swarms. When indoor nests are not found within infested homes, workers usually forage from outdoor nests located close to the foundation. These ants may also damage grass and ornamental plants by feeding on roots, and baiting systems are the preferred method of pavement ant eradication. Pavement ants are abundant in all areas of Texas.
Have you ever found ants emerging from the walls within your home?