Big-Headed Ant Pheidole spp.
This type of ant has two distinct sizes of workers. The
larger ones, called major workers, typically range in size from 1/8-inch to 1/4-inch in length, depending on the
species. The major worker is easily identified by the extremely large size of its head in comparison to its body.
The head of the minor worker is in proportion to its body.
Most are reddish brown in color.
Big-headed ants, like all ants, establish well-defined
trails between the nest and food and water sources. They feed on a wide variety of foods including dead insects,
plant materials, and garbage. The workers are partial to the sweet honeydew produced by aphids, scales, and
mealybugs found feeding on many trees and plants. Fruit trees, roses, and many shrubs serve as hosts for aphids and
may contribute to ant infestations in homes and other buildings. One species, Pheidole megacephala,
establishes large "supercolonies" consisting of dozens, if not hundreds, of subcolonies connected by interlocking
trails. These supercolonies have been found to extend over large portions of a city block, making control efforts
on a single property quite difficult to achieve. This species is more common in Florida and Hawaii but can be
encountered all along the southeast Gulf Coast. They have been known to construct mud tubes that can resemble those
made by subterranean termites, although this behavior is not common.
are soil-nesting ants, most commonly found nesting outdoors beneath stones, logs, and landscape timbers. These ants
also are commonly found inside the soil of potted plants, and many inside infestations may be traced to planters.
In addition, big-headed ants may be found nesting beneath slab foundations and entering through cracks in the slab.
On occasion, these ants will nest inside rotted wood or will excavate old termite-damaged wood to make a
Because big-headed ants are soil nesters, their colonies
are often easy to see due to the piles of displaced soil formed as they excavate tunnels in the ground. Most
colonies are relatively small and easy to treat, but treating infestations involving multiple colonies requires
experience. General tips for limiting ant infestations include:
- Eliminating piles of lumber, bricks, or other debris
that could serve as a nesting site for ants.
- Keeping landscape mulch less than 2 inches thick and
at least 12 inches away from foundations.
- Ensuring the sprinkler system does not spray directly
onto the foundation.
- Sealing as many cracks in the building's exterior as
- Keeping tree and shrub branches trimmed to prevent
touching the building.
- Considering re-landscaping to avoid using plants that
are prone to aphids and similar insects. At the very least, treat such plants for aphids regularly. A
tree/shrub company, such as TruGreen, can be helpful with this task.
get their name because of the major workers’ disproportionately large head; minor workers and fire ants have
similar habits and are often confused for one another.
To lessen the chance of infestation, eliminate piles of wood, stones and other debris to discourage
nesting. Tend to hoses and sprinklers that spray and dampen wooden structures such as sheds. It is also wise to
maintain landscaping and prune any trees to keep branches from coming into contact with exterior
Every colony of bigheaded ants has two distinct types of workers. There are major workers and minor workers. The
major workers have very large heads in relation to their bodies. Bigheaded ants get their name from the appearance
of the major workers. The major workers serve as soldiers and defend the colony. The major workers also use their
large jaws to crack seeds and other food for the other members of the colony.The minor workers are about half the
size of the majors. The minor workers feed the colony, tend the immature ants, and build the nest. There are many
more minor workers than majors in every colony.There are several species of bigheaded ants in the United States.
They are in the family Pheidole. Depending on the species, the color ranges from yellow to dark
reddish-brown. These ants are not known for causing structural damage, but a few species are known as hosts of
Bigheaded ants nest in the ground under rocks or logs. They sometimes make a mound around the nest opening. It
is common for these ants to nest under a slab or beside the foundation of a home. They often enter homes through
cracks in the foundation. Although they do not usually nest inside of homes, they often forage inside homes for
food. Most indoor problems with bigheaded ants begin outdoors.
Outdoors, these ants eat insects and honeydew. When they forage indoors, they seem to prefer foods that are high
in protein. These ants readily make trails between their nest and their food source. It is sometimes possible to
follow these trails and find the nest.
To help prevent bigheaded ant problems, remove as many nesting places near the home as possible. Firewood piles
should be as far from the house as possible. A gap of 6” – 12” between the foundation and any mulch or vegetation
will help discourage these ants from invading the home.
Controlling these ants can involve several treatment methods. If part of the colony survives, the population can
rebound. It is best to leave control to the pest control professional.