Leafcutter Ants

Facts, Identification, & Control

Scientific Name

Atta & Acromyrmex spp.

Appearance

• Color: They are brown, black, or reddish in color.
• Legs: Both genera have long legs.
• Size: Workers measure 1.5 to 12 mm, queens can grow larger than 24 mm in length, and males are approximately 13 to 18 mm long.

How Did I Get Leafcutter Ants?

Infestations in homes are unlikely, because they prefer warm outdoor tropical climates. However, these insects may enter homes in various fashions, such as:

• Cracks in foundation
• Open doors
• In search of food

How Serious Are Leafcutter Ants?

Leafcutter worker ants bite if an intruder threatens their nest or their normal food-gathering activities. They are not aggressive if left alone.

Leafcutter ants can be a serious agricultural threat, as they can easily remove foliage. These pests can lead to an annual decrease in crop yield in affected areas. In North and South America, crop damage from these insects can total a billion dollars.

Signs of 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.

How Do I Get Rid of Leafcutter Ants?

For example, one proactive technique that can be 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.

Service for a leafcutter ant problem begins with a thorough inspection by your pest management professional (PMP). If the inspection results in evidence of infestation, your PMP will provide expert advice on control and will be able help with other proactive tips, as well.

Behavior, Diet, & Habits

Leafcutter ants feed on fungus within their nests. Each species consume 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.

A leafcutter ant nest may descend as deep as six meters. Within the large nests of Atta leafcutter ants, air circulation is controlled by natural movements of warm air from their nests perimeter to its center.

A mature colony of Texas leafcutter ants can contain 100,000 insects, mostly made up of sterile female workers. Depending on their size, female workers are divided into four castes that dictate the functions they perform such as:

• Majors - Soldiers
• Media - Foragers
• Minors - Guard nests
• Minims - Tend fungus gardens

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