There are 22 species of harvester ants in the United States. These insects have six legs, three body parts and antenna, square-shaped heads, no spines on the body, red to dark brown, chewing mouthparts, and up to 1/2 inch long. They have powerful mandibles capable of cutting and carrying grass and small stems to the nest.
In 2003, harvester ants became the first ants to travel from earth to space on the NASA space shuttle. Scientists were studying the effects of space flight and weightlessness on the tunneling behavior during a 16-day flight.
They can be aggressive and deliver a painful sting, sometimes causing allergic reactions.
Nests are constructed consisting of many tunnels where worker ants store seeds, which are the main food source. This ant causes considerable damage to grass and cropland when it constructs nests for its huge colonies.