HOME & GARDEN: Argentine ants are a common household pest

Timothy Daly

Timothy Daly

Recently the extension offices has fielded numerous calls from residents who have observed large numbers of small ants invading their homes. These insects are Argentine ants, which are a common household pest in our area.

Unlike fire ants, they do not sting; however, their presence can be a nuisance. Argentine ants are originally from South America and they became established in the United States more than a century ago when they arrived through coffee shipments. They are 1/16 to 1/8 of an inch long brown in color, and are often found crawling in long, well-organized trails foraging for food.

A mature colony can have 1 million or more worker ants and hundreds of queens.

These ants have the ability to travel in excess of 200 feet with thousands of foraging ants following each other from their nest to a food source. Outside they prefer to feed on the sugar-rich honeydew on trees and shrubs which is produced by soft body insects such as aphids and scale insects. Inside homes they go after sugary drinks and food.

Controlling Argentine ants can be difficult but can be accomplished through a two-step process: eliminate the source where the ants are nesting outside and control those ants that have entered your home.

In the outdoors they prefer to nest in leaf litter, compost piles, firewood, vegetation, mulches, and other areas that provide plenty of moisture and organic material. Do a thorough inspection along the sides of your home, searching for any of these nesting sites and then remove them. Also, cut back vegetation and pull back the mulch at least 18 inches away from the structure.

Remove any vines growing on the side of the house. Check for cracks, crevices, and other sources of entry on the sides of the structure and then seal them up. Clean out your gutters and fix any leaking pipes or faucets. Make sure you put the household garbage in a thoroughly sealed can. On the outside areas, insecticides sprays or granules, such as some of the Bayer Advanced or Ortho products, can be applied directly to the nests or around the structure. To find ant nests, follow trails from the food source back to the nest if possible.

The ants seek protection from the cold weather and begin migrating indoors during the fall seeking a warmer environment and food. Inside the house, clean up and eliminate food sources that are attracting the ants. Make sure all food products are stored either in the refrigerator or in airtight containers and bags top keep the ants out. Clean up drinks and food that have been spilled onto the floor and furniture.

Baits, which are composed of a poison incorporated into a food source that the ants consume, is the preferred method of treating the ants inside the house and poses little risk of poisoning humans if used properly. Small bait stations, such as the Combat and Raid products, should be placed on or near the ant trail. It takes several days for the ants to take the bait back to their nests, where they share it with other ants and the queens eventually killing the colony.

Argentine ants can be quite troublesome and may keep coming back year after year in certain situations. In such cases, a professional pest control service is needed to control the ants. To find a pest control professional, go to the Web site of the Georgia Pest Control Association at www.gpca.org.

Timothy Daly, MS is an agricultural and natural resource agent with the Gwinnett County Extension Service. He can be reached at 678-377-4010 or tdaly@uga.edu.