Here are the 6 most common ants in Massachusetts. Click the name of the ant to learn more about them, how to identify them, what kind of food attracts them, and more.
Acrobat ants can be identified by their light brown to black coloring. The worker ants are 1/8-inch-long, and the queens range up to 3/8-inch-long. They are named acrobat ants because they raise their abdomens over the thorax and head, especially when disturbed. When looking straight down at one, it may look as though their abdomen is heart-shaped. When acrobat ants are alarmed, they emit a repulsive odor. They can also bite.
When worker ants are found indoors, the first place to inspect is the structure’s exterior; one should look for:
- trailing ants on the foundation
- bits of foamboard insulation which would indicate a nest behind the exterior sheathing or siding
- trailing ants on all wires, utility lines and pipes coming into the walls
- trailing ants on tree and shrub branches in contact with the wall
- signs of excessive moisture such as water leaks, peeling paint on wood thresholds, soffits, window frames, trim and molding
If one is looking for acrobat ants in the yard, one should inspect:
- tree cavities
- dead tree limb
- loose bark for ant nests
- under rocks and debris lying on the ground
Acrobat ants feed on honeydew from aphids and mealybugs which they usually tend or “herd.” They also feed on live and dead insects, including termite swarmers. Indoors, they show a slight preference for sweets and high-protein foods such as meats.
Odorous House Ants
Odorous house ants are 1/8 inch long and are brown to black in color. The thorax profile is unevenly rounded and you cannot see the abdomen from above. These ants do not sting or bite; however, the workers emit a disagreeable, rotten coconut-like odor when crushed. One colony may have up to 10,000 ants and several queens. Development time is 34-83 days depending on temperature, so the most common swarms are from May to mid-July.
Facts about odorous house ants when found inside:
- They can be found behind siding, brick veneer, and stucco.
- They can also be found in wall voids, especially around hot water pipes and heaters, and in cabinets.
- They prefer sweets and high-protein food such as meats and cheese.
- They tend to go inside when they need a food source and during rainy weather.
Facts about odorous house ants when found outside:
- They are often found in nests of larger ants, in exposed soil, and under objects
- They feed on insects, honeydew, and plant secretions and seeds
Pavement ants get their name from commonly being found under cracks in pavements. Workers are 1/8-inch-long and queens are 3/8-inch-long. Their bodies are brown to black in color, and their legs and antennae are paler. Their body is unevenly rounded. Pavement ants do have stingers but seldom use it. A pavement ant colony can be comprised of several hundred to several thousand ants. Development time varies from 36-63 days.
Facts about pavement ants when found inside:
- Winged reproductives appear from February into early June.
- They occasionally nest in walls, in insulation, and under floors.
- They mostly nest in ground-level masonry walls of the foundation and especially near some heat source in the winter.
- They often follow pipes, which come through slabs for access to upper floors of buildings.
Facts about pavement ants when found outside:
- Winged reproductives appear outside primarily in June and July.
- They are typically found in nests under stones, in cracks in pavement, and next to buildings.
- They enter buildings through cracks in the slab and walls, slab expansion joints, utility and heat duct penetrations, and the natural openings of buildings.
These ants feed on almost anything including insects, honeydew, seeds, plant sap, and household foods such as meats, nuts, cheese, honey, and bread.They show a preference for meats and grease. They forage in trails, and for distances of up to 30 feet.
The citronella ants get their name from the lemon verbena or citronella odor they emit when threatened. It is most noticeable when the ants are crushed. They are very common in the eastern United States and are frequently confused with termites when they swarm into the living areas of homes. There are two subspecies of the citronella ant.
In both species, the swarmers (winged ants) may vary in color from the more common light yellow to a dark reddish-yellow or light brown. The workers are typically yellow with less color variation than the swarmers. The workers are 4-4.5 mm-long with 12-segmented antennae. The swammers are approximately twice the size as workers with dark, smoke-colored wings. They are subterranean insects that feed on the honeydew (excretions) of aphids and mealybugs feeding on the roots of shrubs.
Colonies typically have mounds of soil around the openings where excavated soil is deposited. They normally go unnoticed unless the swarmers enter through expansion cracks in slabs or around door openings. Although these intrusions may alarm homeowners, the ants will not reproduce within the home nor will they attack stored goods or structures.
These ants are of particular importance in hospitals where they will enter wounds, enter in-use IV bottles, seek moisture from the mouths of sleeping infants, etc. More than a dozen pathogenic bacteria have been found on pharaoh ants collected in hospitals. They are also common problems in food-handling establishments such as hotels, grocery stores, and apartment complexes. Pharaoh ants have a wide preference in food, ranging from syrups to fruits, pies, meats, and dead insects.
Worker pharaoh ants are 1/16-inch-long and the body is yellowish to orange, with a dark tip at the rear. They have a stinger but it is rarely used. Queens are about 1/8-inch-long and slightly darker in color than workers. Males are about 1/16-inch-long, winged, black in color, and possess straight antenna straight, not elbowed. The males are very gnat-like in appearance. The colonies have anywhere between thousands to several hundred thousand ants. Workers live about 9 to 10 weeks, queens live 4 to 12 months, and males die about 3 to 5 weeks after mating.
Facts about pharaoh ants when found inside:
- They nest in warm, humid areas such as wall voids, baseboards, in furniture, and between linens.
- The workers forage widely from the nest in search of food and water, and establish trails to food and water sources.
- They commonly use electrical and telephone wires as a highway system to travel through walls and between floors.
Facts about pharaoh ants when found outside:
- They nest in debris collected on flat roofs.
- Those nesting inside will venture outside onto flat roofs in warm weather for water and food (dead insects). They typically enter and exit via poorly caulked and defective windows, under the flashing, and through weep holes in brick veneer.
- In the temperate northern areas of the United States, they usually cannot survive outdoors year-round.
Note: Do not attempt to control pharaoh ants using DIY ant control because this may make the problem worse. Nor should one disturb/contaminate the foraging ants or the bait stations that have been installed by the technician.
Pharaoh ants are treated differently than other species—the typical use of repellent liquid or dust insecticides (versus non-repellent baits) actually makes the situation worse by causing the colony to fracture (“bud”) into several colonies. Baiting is usually the only method of effective control for pharaoh ants. If the pharaoh ant infestation is in a multifamily building, the only way such an infestation can be eliminated is inspection and treatment of the entire building.
This is the largest genus of ants in America north of Mexico, containing about one-sixth of our entire ant fauna. They are commonly called thatching ants because of their habit of constructing a mound or thatch of plant material, often grass. Field ants rarely nest in homes but occasionally enter in search of sweets. They are commonly found:
- Near small trees, shrubs, or rocks
- In the cracks of sidewalks
- Along foundation walls
- At the base of trees
Field ant workers measure about 1/4 inch long and may be brown, black, reddish or a combination of these colors. Although no stinger is present, these ants will bite and spray pungent-smelling formic acid onto the persons or animals provoking them. Colony size varies considerably, for example, colonies of some species have nests of about 20,000-94,000 ants.
Field and thatching ants feed primarily on honeydew, mealy bugs, scale insects, etc. found on trees and shrubs. However, some are also general scavenger-predators and are attracted to meat.