How to Get Rid of Leaf Cutter Ants

If you have an active Leaf Cutter Ant infestation, follow this guideline for Leaf Cutter ant control treatments.

Ant Control Products

Leafcutter ants are also known as "cut ants" or "parasol ants." Leafcutter ants originate mainly in the Americas. They are found in eastern and south-central Texas. They also can be found in parts of western Louisiana. Leafcutter ants are not commonly found in subdivisions but are considered an agricultural, rural pest. Leafcutter ants are serious agricultural pests in Central and South America, causing millions of dollars in crop losses. The foraging Leafcutter worker ant is reddish or rust-colored.

Identification and Inspection

Identification

They range from 1/12 to 1/2 inch in length.
Leafcutter ants have a color range of orange/brown to reddish black.
The winged reproductives of the Leaf Cutter Ants can be 1-1/4 inch long.
The Leafcutter ant has a spiny body and long legs.
Also called "parasol ants," these ants will cast a shadow as they carry their leaf cuttings. It looks like a mini umbrella.

Distribution: Southern US, South and Central America, and Mexico

Queens: They are about 1 3/16" long, chubby, and brown. The Leafcutter queen can live up to 15 years and lay 1000 eggs daily. There is one queen per colony. They are often confused with large wasps. Winged reproductives swarm in late spring.

Workers: 0.31 &dash; 0.47 inches long, with a light brown/orange color. They have spikes on their backs.

Major Workers: 0.70 inches with large head and mandibles to cut vegetation

Colony Size: large colonies; up to several million workers which may include small satellite colonies

Inspection

Their foraging trails can go a couple of hundred feet from a nesting area. So when inspecting, know that these ants may prey on a tree or shrub in one area, but the nest may be far away. Look for their mounds and trails.

Diet

These ants primarily eat fungus. The worker ants build up a fungi garden from leaf fragments in their colonies.

Leaf Cutter Behavior

Leafcutter ants damage vegetation because they remove foliage to carry it back to their nests. They have been known to remove all the needles or leaves from a tree in one night. At night, workers will pick out a shrub or tree, swarm over it and cut circular-shaped pieces from the leaves.

The leaves or needles are not eaten for food but used in another manner. It is chewed into a material much like pulp, creating a "fungus garden." This pulp produces a fungus that feeds the colony.

During the summer months, Leafcutter ants forage at night. The worker ants will forage during the day during the spring and fall months unless it is rainy or overcast. They are attracted to lights on buildings. After a major swarm, they can be found in a large number on exterior walls of buildings.

Look for "trails of leaves" when inspecting their trails to find their mounds. These foraging workers bring back fragments from leaves.

Damage

Leafcutter ants can do significant damage to plants within a few hours. The damage may resemble damage seen from other leaf chewing insects. Leafcutter ants can attack pine trees but prefer green foliage. Seedling pines are frequently damaged during the winter months when green plants are scarce.

Leaf Cutter Mounds and Nests

A Leaf Cutter Ant nest can cover up to many hundred square feet in area coverage.

These nests can extend as far as ten-twelve feet into the ground.
Leafcutter Ants prefer to nest in well-drained sand or loamy soils.
You may find craters of loose soil deposited above their nests, with many entrances.

Since Leafcutter ants like high moisture areas, search in those areas. Typical areas are drainage ditches, streams, and creek beds. Mounds are formed in the shape of a large funnel. Leafcutter ants can have colonies up to two million according to Texas A&M Extension.

Leafcutting ant colonies may have up to five fertile queens, producing eggs. These eggs develop into larvae. Most of the larvae turn into sterile worker ants, but some develop into winged reproductive ants in the springtime. These swarming reproductives are much larger than the worker ants; they are darker with long brownish wings.

Get Rid of Leaf Cutter Ants

Ant Trails and Inspection

Leafcutter ants feed off the fungi that have been stored and cultivated. There are no ant baits on the market (sugar-based or protein/grease-based ) to mimic this needed food source to work effectively.

Conduct a thorough inspection to find all the mounds before they become larger and more extensive.

Drenching: It is recommended that you drench the mounds with a diluted residual insecticide such as Conquer Insecticide or Dominion 2L at 1 oz per 5 gallons of water.
Spraying An Insecticide: Another method would be to spray non-repellent insecticide labeled to spray in the yard. We recommend Dominion 2L. When spraying the Leafcutter Ant trails as a residual insecticide, use 3/4 oz per gallon of water. The trails are very distinctive, looking like a worn path of bare ground.
Since Leafcutter Ant nests may extend deep underground and are often located near bodies of water, call your local extension agency for their recommendations before using any insecticide spray.

How To Prevent Leafcutter Ants

Conduct a thorough inspection to find all the mounds before they become larger and more extensive.

It is almost impossible to prevent Leafcutter ants. However, spraying a repellent insecticide like Bifen IT, may scatter them enough before they start foraging and trailing.
The best method is to watch for early mound development and drench them with a non-repellent insecticide like Dominion 2L.
Drenching or spraying the mounds with Dominion 2L or Conquer is the best way to kill out the Leafcutter ants.
Conduct a thorough inspection to find all the mounds before they become larger and more extensive.

Written by our resident pest control expert Ken Martin.