Red Imported Fire Ant, Solenopsis invicta Buren

Red imported fire ants are native to the central parts of South America. Scientists believe they arrived in Mobile, AL, around 1930 in soil that had been used for ship ballast. These aggressive ants proceeded to spread and now infest all or part of 14 Southern and Western States.

Fire ants look a lot like ordinary ants. They are 1/8 inch to 1/4 inch (3-6 mm) long and reddish brown. Fire ants are probably best distinguished by their aggressive behavior and characteristic mound-shaped nests. People and fire ants often come into conflict when people accidentally bump into these mounds while mowing, step on them, or otherwise disturb them in the normal course of farming or family life. When their nests are disrupted, fire ants swarm out to bite whatever hit their home—pets, kids, or lawn equipment.

Anyone who has had an encounter with them can tell you why these pests are called fire ants. They clamp onto their target with powerful jaws and sting it repeatedly. Each sting injects venom, which causes a burning sensation and itching blisters that can become infected. Red imported fire ants attack and kill newborn domestic animals, pets, and wildlife and destroy seedling corn, soybeans, and other crops. They can even remove bands of bark from young citrus trees, often killing them. The ants' nests can grow up to 2 feet (60 cm) high and are hazards in yards, parks, and other recreational areas. This is one ant you don't want to see at your picnic!