The Argentine ant is native to Argentina and Brazil. Experts believe it entered the U.S in the late 1800s via ships transporting South American coffee. Argentine ants can be identified by their musty smell when crushed. They vary in color from light brown to dark brown. The larger queens range up to a quarter-inch in length and the workers are about one-tenth of an inch.
Although Argentine Ants are a major nuisance pest, they cannot sting.
Argentine ants always travel to and from their nests in trails that are sometimes hundreds of feet long and may contain thousands of ants. Trailing is heaviest in early morning or late afternoon. These ants are less active when the surface temperature exceeds 90 F. They might continue to trail in shaded or protected areas. Their natural food preference is “honeydew”, a sweet substance produced by sap-sucking insects like aphids.
Outside, Argentine ants tend to form shallow nests in moist places, such as under stones, logs, potted plants and landscapes mulch, as well as along sidewalks. Often, their nests maybe also found at he base of plants and trees where honeydew-producing insects live. They may invade buildings in large numbers when conditions outside are too wet or too dry, or when there is a decrease in honeydew. To enter structures, they search for cracks, crevices or holes, utility lines, cables and wires, traveling along tree and shrub branches. Once inside, they may crawl along utility wires and pipes in walls, searching for food and nesting sites. Indoors, these ants usually nest near a moisture source, such as in wall voids near water pipes, sinks, bathtubs or showers, or in potted plants. Once foragers find food, sentinels go back to the nest and provide an odor trail for others to follow and join the meal. Hundreds of Argentine Ants can be quickly recruited to contaminate food they find indoors. They prefer a like honeydew and plant secretions, or sugar, syrup and fruit juice. But they’ll settle for almost anything else, including meats, eggs, oil and fat.
If you think argentine ants have infested your home, it is VERY important to immediately contact a certified, licensed pest management professional for inspection. Make sure to let them know about any structural leaks or moisture problems.