Common Name: Leafcutter Ant
Latin Name: Atta
Common Family Name: Ants
Latin Family Name: Formicidae
Other Names: Cutter ants, fungus growing ants, cut ants, parasol ants
Origin: Most species of Atta are native to Latin America, but it also occurs in the United States along the Gulf Coast states through Texas to Arizona. Atta texana is a common and very damaging species in the southern states.
Biology: Leaf-cutting ants feed on a fungus that grows on sections of leaves that they harvest, and propagate within their underground nests. Colonies may be enormous, with many thousands of workers that are capable of completely stripping a tree of all vegetation in a single night. The nest may occupy an area over 300 to 400 square feet in area and be up to 8 feet deep, with many openings. Workers forage in distinct and obvious trails, and workers are highly polymorphic. These ants rarely invade a structure, but they can do tremendous damage to ornamental trees and shrubs. The reproductives, or swarmers, are huge, being over an inch long, and their flights are usually in mid-spring. They are attracted to lights and great numbers of them may be found on residential porches at night.
Identification: Leaf cutting ants are double-node ants and are capable of inflicting a painful sting. Workers are usually a dark reddish to reddish brown, and are distinctive by having 3 pairs of spines on the top of their thorax, as well as a pair of spines at the back of the head. Their mandibles are very large, designed as scissors used in cutting off sections of leaves.
Characteristics Important in Control: These are rarely a structural pest, and no control is needed indoors. Control measures outdoors consist of locating the nest and treating directly into it. Bait products will not be accepted by Leaf-cutting ants.