Ants can cause a nuisance problem by foraging for food inside a home and forming nests in unwanted areas, such as playgrounds or lawns. Most nuisance ants nest outdoors, but pharaoh ants and carpenter ants are two types of ants that can nest indoors. Ants are commonly associated with aphids and other honeydew-producing insects. Ants collect and feed on the sweet, sticky substance that these insects excrete. In turn, ants protect these pest insects from attack by lady beetles and other natural enemies. Ants may be attracted to food in a patio area, so an important step to any ant-control program is to remove their food attractions. Crumbs, grease, food scraps and other items are sought by foraging worker ants, and they will return to those areas where food is found. To prevent ants from foraging indoors, residual spray treatments can be applied around foundations and patio perimeters. For more permanent control, the nest should be destroyed. Dusts usually are more effective on nests than sprays because dusts, such as hydramethylnon, are more readily tracked into the colony. Slow-acting insecticides allow the forager to return to the colony with the "poisoned" food which will kill the queens and young ants. Several brands of ant baits or traps are available. If ant-feeding bait is used as a control, all other food sources should be removed so the insects concentrate on the bait. Homemade ant bait can be made by mixing a small amount of boric acid into a food source for foraging ants. Boric acid is sold as a disinfectant in pharmacies and as an insecticide in many cockroach powders such as Roach-Prufe. To prepare the bait, select something sweet like honey or jelly, or something greasy like peanut butter (apple jelly or honey mixed with peanut butter is a common bait); add boric acid at 1 to 2 percent concentration (approximately 1 teaspoon of boric acid per cup of the food bait). Place this mixture in an area visited by ants. If the bait is successful, the ants should be gone in ten days to two weeks. Note of caution: Although relatively nontoxic, boric acid or any other bait should be kept away from children and pets--placed in out-of-the-way areas or enclosed in "bait stations" such as straws. Also boric acid is a soil sterilant and should never be placed on soils where plants are growing or that may be used for growing plants in the future. Some ants, such as carpenter ants and pharaoh ants, require more specialized treatment for control. For more information see the fact sheet, Ants in the Home.

Browse related Faqs by tag: horticulture, integrated pest management, ants, colorado