Every colony of big-headed ants has two distinct types of workers: major workers and minor workers. Big-headed ants get their name from the appearance of the major workers - they have very large heads in relation to their bodies. The front half of the major's head is sculptured, while the back half is smooth and shiny. The major workers are about 1/8 inch in size serve as soldiers and defend the colony. The minor workers are small (1/16 inch) reddish brown ants and they feed the colony, tend the immature ants, and build the nest. There are many more minor workers than majors in every colony.
The big headed ant can be found nesting in disturbed soils, lawns, flowerbeds, under objects, such as bricks, cement slabs, rocks, logs, or flower pots, around trees or water pipes, along the base of structures, and walkways, where displaced soil is usually observed from the action of ants digging below the surface. Well-cared-for lawns may have big head ant infestations that are less noticeable, except along the edges where lawns meet walkways where piles of soil are often deposited. Big headed ant populations expand into neighboring areas by following along these lawn-walkway edges or roadways. Big headed ants can quickly move into new areas to establish nests and kick out other ant populations.