Pavement Ants in Southern New England

The pavement ant is representative of a broad group of ground-nesting ants that are found throughout the northern and eastern parts of the United States. Pavement ants live in colonies with a social structure. Homes and buildings with slab-on-ground type construction are particularly prone in invasion by pavement ants.

When pavement ants (Tetramorium caespitum) come out of hibernation, it is every ant on deck. Large numbers of these small 3-4 mm, usually dark ants can emerge inside structures, even in the coldest months. Most sightings occur on floors and lower areas of the structure. Heated basements, radiant heating under slabs, open crawl spaces, increased temperatures near fireplaces, woodstoves, heating systems can provide the warmth needed to stimulate their activities.

What Do Pavement Ants Eat?

Pavement ants will eat almost any kind of food.  They are drawn to sweets, starches, greases, meats, fruits, and vegetables are all acceptable as food. Pavement ants need moisture and will travel some distance to find a source and will not leave a scrap of food on the floor. Once abundant food sources are located, foraging ants range out in search of new discoveries. Foraging areas may extend into other areas of the structure such as countertops, stovetops, dirty microwave ovens, spills in cabinets, walls, and even beds as worker ants investigate the area.

Why Do I Have Pavement Ants?

If you have pavement ants inside your home, they are likely looking for warmth, moisture, and a food supply for their colony to continue to grow and develop. The workers are sent out like “little trucks” to forage and gather these basic needs. Once they have gained entry into your home they will search for food and moisture. This is especially true during the winter months when cold weather limits their outside activity. When they appear on cold winter days they have probably exhausted their stored food supply in the nest and they are out looking for additional food or moisture. They will appear inside homes and buildings during the summer when the conditions outside are extreme. This might occur after very heavy rain when the ground is saturated or just the opposite, during periods of drought when the ground is dry and they need moisture.

Why Do Pavement Ants Swarm?

Pavement ants are usually responsible for making the little piles of sand along driveways, in patios, and along masonry edges.  Pavement ant swarming is the way that they start new colonies. This swarming takes place several times a year. Male and female pavement ants fly up and away from established colonies in a mating frenzy. Most die, un-mated, and end up as food for many animals, or are recycled through decay.

Most swarming occurs between May and July. When this massive event takes place billions of queen pavement ants have been fertilized by the tiny male pavement ants (1/3 the size of the queen). When mating takes place, the queens cut their wings off with their sharp mandibles. Fertilized queen Pavement ants need to find a place to hide and fast. Once an acceptable location is located, she will dig an initial chamber to lay the first eggs. Once hatched, the queen will feed the tiny larvae.

Do Pavement Ants Have Wings?

The winged ants or “swarmer’s” are the kings and queens. Researchers are not certain of the exact cause for the pavement ants to swarm out but it appears to be related to the size of the nest, the age of the nest, and perhaps the weather conditions.

Pavement Ants After Swarming

Within a few weeks after swarming, the first adult ants will have hatched and begun the duties of caring for the eggs, larvae, pupae, and foraging for food to feed the young pavement ant colony. Food sources naturally include sweet and greasy substances: fruit, chips, soda, sugar, syrup, bacon, pet food, baby formula, honey, meat, fat, dead insects, and dead animals. Adult ants seek out food sources creating a pheromone trail back to any discoveries. Other ants quickly arrive at the new feeding site, even if the food is gone; the pheromone trail is still there recruiting other workers to that area. All food items are promptly brought to the developing larvae.

Pavement ant larvae are the stomach of the ant colony. Larvae digest food material and secrete a nutritious fluid that the adults rely on for survival. As the larvae develop, they pupate in small cocoons. Pupae become adult ants, now able to work for the colony or become reproductives that will benefit the species as a whole and leave the colony. The queen pavement ant uses her pheromones to control the makeup of the ant colony. When the colony is mature, most of its energy goes into producing reproductives for swarming. To produce reproductives, many workers must forage as soon as possible. This accounts for the fast increase of activity once a pavement ant colony wakes up.

How To Get Rid of Pavement Ants

If you have pavement ants, you want them gone right away. The use of baits and/or liquid sprays is currently the most effective method of control.

Pavement Ant Baiting:

Baits are very effective and efficient in eliminating a pavement ant infestation provided the ants would accept the bait. Ant baits contain a slow-acting poison and are formulated as gels, solids, and liquids. The worker ants are unable to eat solid food so they gather the bait and carry it back to the nest where they feed the immature stage (larva). The larvae process the bait and then through a process known as trophalaxis they regurgitate a liquid to feed the queen and the other workers. The workers get their “reward” so they will continue to go out and bring back more food and do the other work required by the colony. This process spreads the slow acting poison throughout the nest and causes the entire colony to die off. This is a very successful method provided the ants take the bait. Sometimes, and for reasons that are still unknown, pavement ants will not accept certain baits. When this occurs, the choice is to try a different bait material or to use a liquid insecticide.

When using baits, always read and follow the directions on the label of the product you are using. Baits need to be placed in areas inaccessible to young children and pets. During warmer weather, look for pavement ants outside crawling on the ground close to the foundation. Watch where they go, then place baits on and near their trails. They are likely to gather around the bait or immediately pick it up and transport it back to the colony. It is not unusual for many pavement ants to suddenly appear after the bait is placed. This is normal foraging activity so please do not disturb the ants or apply any insecticides to kill them. Let them feed on the bait. Over the next three days inspect the feeding sites and replenish the baits that are consumed. Within a week the pavement ants should be gone. If the foraging activity continues longer than a week you may need to place more baits or consider the use of liquid sprays.

Liquid Pavement Ant Insecticide Treatment:

Liquid spray treatments are effective in killing the ants you see actively foraging around inside or outside of your home. Liquids may also be applied directly to ant mounds found in the lawn and to ant mounds found along foundations and in cracks of sidewalks, patios, and pavement. For general protection, especially when you cannot locate the nest you can apply insecticides where the ants gain entry, where they hide, and where they search for food. Inspect and treat these areas with liquid pavement ant treatment:

  • Door thresholds
  • Cracks in the foundation wall
  • Window sills
  • Edge of carpeting
  • Pipe holes
  • Window frames
  • Door frames
  • Behind appliances
  • Plumbing voids
  • Cracks in basement floor
  • Under baseboards
  • Top of mudsill

Outdoors, treat up under the siding where it meets the foundation, the ground directly against the foundation along the perimeter of the house, and the expansion joint between the foundation and the driveway, sidewalk, or patio. It may take one to three gallons to thoroughly treat the exterior of a typical three or four bedroom home.

If you believe that your home or business is experiencing pest control issues, contact an F&W Pest Control professional today for a free inspection and quote.

Sign Up for a Pest Program