How to Safely Eliminate Household Ants

Most household ants cause little damage, but they often become a nuisance. Some also infest food or weaken wooden structures. Pharaoh ants in hospitals can transmit diseases from one patient to another. Depending on the species, ants feed on starches, meats, fats and sweets. They build nests in the soil, behind moldings, in wall voids and other protected sites. Species identification can help you obtain details such as their food and nesting preferences, and you can use the information to eliminate the ants.

Things You'll Need

• Sticky traps
• Water
• Water containers
• Food morsels
• Insecticidal granules, liquids, dusts or aerosol sprays
• Insecticidal baits

Instructions

1. Seal gaps and cracks in the exterior walls of the house to prevent more ants from coming inside. Apply an insecticidal barrier containing permethrin, bifenthrin, carbaryl, cyfluthrin or deltamethrin to keep ants out of the house. These insecticides come as liquids, granules and dusts. Treat points of entry if you can identify the locations. Otherwise, create a band of insecticidal barrier about 2 to 4 feet wide around the entire building.

2. Clean surfaces and vacuum the carpet to remove any food debris that can invite ants. Rinse reusable containers and eating utensils thoroughly before storage. Take out the trash every day and don't leave pet food out continuously.

3. Place sticky traps or water in containers to prevent ants from reaching plants and other items.

4. Spray the ants you see if you have a light, seasonal infestation. Aerosol or liquid sprays that kill ants upon direct contact contain permethrin, bifenthrin, cyfluthrin, cypermethrin, deltamethrin or tralomethrin as the active ingredients.

5. Place food in an area where you have seen ants. Wait for the ants to come and follow the ant trails to find the nest.

6. Treat outdoor ant nests with insecticides that contain permethrin, carbaryl, bifenthrin, cyfluthrin or acephate. Drench the nest with an insecticidal liquid or spread insecticidal granules over the nest and water them in. Reapply insecticide according to label instructions if ants continue to appear.

7. Treat ant nests in inaccessible voids, cracks and crevices with insecticidal dusts. Drill small holes in the wall about 1/8 inch in diameter and puff an insecticidal dust that contains deltamethrin or permethrin inside. Don't apply more than the amount recommended by the product label because ants will avoid contact with too much dust.

8. Use insecticidal baits to kill ants if you can't find the nest. These baits contain abamectin, fipronil, sulfluramid, disodium octaborate, orthoboric acid or propoxur as the active ingredient. Worker ants will feed on the bait and bring it back to the nest to share with other ants, allowing the insecticide to eventually kill the whole colony. Baits can take several weeks or months to kill ants.

Tips & Warnings

• Don't use water to flood ant nest because this method doesn't effectively eliminate ants.

• Don't use spearmint gum, red pepper, orange peels or herbs as repellents because they don't keep ants away.

• Don't drench ant nest with gasoline because it pollutes the environment and doesn't effectively kill ants.

References

• University of Minnesota Extension: What to Do About Household Ants
• North Carolina Cooperative Extension: A Guide to House-Invading Ants and Their Control
• Texas A&M University: House-Infesting Ants and Their Management