Leafcutter Ants

Facts, Identification & Control

Scientific Name: Atta & Acromyrmex spp.

Appearance

leafcutter ant picture
There are two genera of leafcutter ants: Atta & Acromyrmex leafcutter ants. Both genera have extremely long legs. Workers measure 1.5 to 12 mm. Queens can grow larger than 24 mm in length, and male leafcutter ants are approximately 13 to 18 mm long. Some leafcutter ants have brown or black colors, while others may appear to be reddish in color

Behavior, Diet & Habits

Leafcutter ants can be a serious agricultural threat. In extreme cases, leafcutter ants are capable of destroying entire citrus trees in the span of a day and can lead to an annual decrease in crop yield in affected areas. In North and South America, damages caused by leafcutter ants amount to $1 billion in losses.

Leafcutter ants dwell in warm areas, and they are unique because they cultivate and feed on fungus within their nests. Each species of leafcutter ant consumes a different species of fungus, tending the fungi with grass and leaf clippings. These fungi secrete warning chemicals when an ant introduces a leaf to the nest that is toxic.
Within the large nest of an Atta leafcutter ant, air circulation is controlled by natural movements of warm air from the nest’s perimeter to its center. A leafcutter ant nest may descend as deep as six meters.

A mature colony of Texas leafcutter ants could contain 100,000 insects, mostly made up of sterile female workers. Depending on their size, these female leafcutter workers are divided into four castes—major, minor, media and minim—which dictate the functions they perform. Major workers are soldiers; minors guard the nests and trails; media forage for food; and minims tend the fungus gardens.

Leafcutter worker ants will bite if an intruder threatens their nest or their normal food-gathering activities. Leafcutter ants are not aggressive if left alone to do their leaf-gathering business.

Reproduction

Similar to most other ants, the role of reproduction falls to the queen. While the queen lays the eggs, the workers care for the larvae. Four to five queens may inhabit one colony and they may survive for many years.

Signs Of An Infestation

The most visible evidence of leafcutter ant activity is a trail of ants carrying bits of leaves or other organic material back to their nest.

More Information

Providing service for a leafcutter ant problem begins with a thorough inspection by your pest management professional. If the inspection results in evidence of leafcutter ants, your pest management professional will provide expert advice and assistance. For example, one proactive technique that may prove helpful to prevent leafcutter ant damage to specific landscaping plants is to put a piece of smooth plastic, coated with an adhesive compound, around the base of the plant. This should trap the ants before they cut and remove the leaves. Your pest management professional will be able help with other proactive tips, as well.