Field Ants

What Are They?

Field ant is a name that many people use for a group of ant species  that live in yards. These pests construct large mounds that can become obtrusive. Though the ants prefer living outdoors, they will occasionally sneak into homes.

What Do They Look Like?

Depending on the species, field ants range in color from black to reddish brown. The pests are often confused with carpenter ants because they’re both larger than average. However, field ant thoraxes have a distinct shape that helps with identification.

Field Ant

Vs. Other Ants

Many field ant species are known by other names as well. People confuse some field ants with ants that are pests of people and their property.

The black field ant is often mistaken for the black carpenter ant. The red and black field ant known as the Allegheny mound ant is frequently mistaken for the fire ant. A careful examination can show the difference, but homeowners are often startled to see one of these ants around their home.  Field ant thoraxes have a distinct shape that helps with identification.

What Do They Eat?

Field ants feed on insects and honeydew. The field ant workers care for aphids that produce the honeydew.  Field ants seldom infest homes, but the workers may come inside looking for food. They are often seen on decks and patios foraging for food that may have been spilled.  They will also enter homes to forage for sugary pantry goods.


Field ants make their nests in the soil. They usually make their nests in fields and pastures. The workers often build a mound on the surface with the dirt that they excavate from the tunnels. Field ants can become pests when they make their nest in a lawn, a golf course, or a sports field.

Life Cycle & Colony

Colonies have one queen, and she’s responsible for all reproduction. Eggs develop into either sterile worker females or male drones. These colonies can survive for over 10 years.


Field ants can also become pests in late summer when the winged ants swarm out of their colonies. The male and female ants fly in large numbers to find mates and start new colonies. They often land on buildings and sometimes they get inside.

Problems Caused By Field Ants

They Create Mounds

Field ant mounds can grow as large as three to four feet wide and over two feet tall. They’re unsightly and cause problems when residents try to mow the lawn.  These mounds are the most obvious sign of their presence.

The pests also inject formic acid into surrounding plant roots, causing any vegetation that might shade their mounds to die.

They Can Bite

In addition, field ants will bite when disturbed. They use their mouthparts to pinch people’s skin, then squirt the same acid they use to kill plants into the wound. As such, these bites feel as painful as a sting.

Ways to Get Rid of Them

If winged field ants get into the home, a vacuum cleaner is the quickest solution. Take the vacuum bag outside and dispose of it in the trash. Keep trash containers closed with lids that fit tightly. Store cans that are being saved for recycling outside and away from the house. Check the exterior doors to be sure they close tightly and replace any missing weather-stripping.

Prevention Tips

Residents can limit field ants in their kitchens by caulking cracks in building foundations and replacing broken window screens. However, it’s harder to keep the pests from nesting outside. Clearing piles of firewood and other debris can help, but there’s no sure way to keep field ants from building a mound.