It is probably safe to say that most people are familiar with ants and have seen them around their homes at one time or another. Ants are commonly depicted as picnic invaders because people see them crawling around on their food. When ants enter a home, they are often searching for sweets or protein, though food preferences can vary widely by species.

Facts About Ants


Common Species of Ants

argentine ant
carpenter ant
pavement ants
pharaoh ant
fire ant

There are hundreds of species of ants throughout the U.S. and Canada, yet only about 25 of these are encountered in and around homes. Ants are social insects, which means that they live in colonies and work together for survival by creating nests, finding food, and caring for the queen and the young. Every adult ant in the colony has a job.

The many species of ants vary in appearance. Sometimes even a pest expert needs to examine an ant under a microscope to determine exactly what type it is. However, all ants have three body parts: the head, thorax, and abdomen. Each of these segments is divided by a very narrow area.

Identification / Appearance

What Do Ants look Like?

ant anatomy
click to enlarge

Generally speaking, most ants range anywhere from 1/16’ to 1/2’, though the queens are larger and tend to range from about one–quarter inch to as much as a full inch.

Though colors can vary even within one species, most varieties of ants are yellowish, light brown, brown, black, or reddish.

Life Cycle

An ant’s life cycle consists of four stages:

  • egg
  • larva
  • pupa
  • adult.


An ant colony contains three classes of adults, known as castes (pronounced “casts”). These are reproductive males, workers, and queens. Each one plays a role in sustaining the colony.

Where Do They Build Colonies?
When ants set out to establish a colony, they look for sheltered, moist areas with a nearby food source. Items such as rocks, mulch, wood, or vegetation keep the soil moist and minimize evaporation. Poor drainage and leaks around a home can also provide suitable moisture levels for ants.


What Do Ants Eat?
Food preferences, like the ant species themselves, vary widely. Some will eat a wide variety of food, while others prefer just a few types. Eating preferences can also change during different periods, such as a time of high egg production.

Problems Caused by Ants

Ants can be bothersome to humans for a number of reasons. They can contaminate food, establish nests in people”s yards, and inflict painful bites. They can occasionally transmit disease or even kill young livestock.

Damage to Homes
Some ant species, such as carpenter ants, can cause damage to wooden items and structures. However, a number of ant species are not particularly harmful to people or damaging to homes. In fact, some are able to help keep other nuisance pest populations under control.

Ant Control

There are many products available for ant control. There is an insecticide for almost any situation. Ant control insecticides are available in the form of liquids, dusts, and baits.


There are liquid insecticides available that are ready-to-use and others that must be mixed. There are liquid insecticides that repel the ants. People use these to keep ants from entering a building. There are other liquids that the ants cannot smell. These are sometimes used when ants have a nest outside but they are coming into a house for food or water. Since these insecticides do not repel the ants, they will walk through the treatment and pick it up on their bodies.

The dust insecticides are effective for treating hollow spaces, like the voids inside of walls. Many people use dust to treat the nests of carpenter ants. The dust remains inside the wall and the ants walk through it. Later, when they clean each other, the ants swallow some of the dust.


Ant bait is a combination of a food that the ants will eat and an active ingredient that will be toxic to the ants. Baits for ant control come in several forms. Liquid bait, gel bait, and granular (chunky) bait are the most commonly used forms. Since ants’ food preferences change, it is sometimes necessary to place more then one kind of bait near the ant trail so the workers can choose the one they will accept.

Ant baits are made with several kinds of active ingredients. The most commonly used bait contains a stomach poison. The workers share the bait with the other ants in the nest. As each ant digests some of the bait, it gets a lethal dose. Another type of bait that is widely used contains an Insect Growth Regulator (also called an IGR). The IGR prevents the development of new adult ants. As the older ants die, there are no replacements and the colony dies.

The assortment of ant control products helps assure the treatment works. Since there are many kinds of ants living in many different locations, it would be difficult to get control with only one product. Always follow label directions for mixing or applying insecticides.