Learn which plants thrive in your Hardiness Zone with our new interactive map!

Ant Lawn Treatment

By Kimberly Sharpe ; Updated September 21, 2017
Ants build unsightly mounds in the lawn.

Ants pose problems for the home landscape lawn, even though they do not consume grass. They build unsightly mounds that can attain a diameter of up to 24 inches, according to the University of Iowa. The red fire ant produces painful bites which makes a yard unpleasant for children or pets. Their bites can be fatal for allergic individuals. Ants also infest food left outside and a few species pose a threat to the home structure by consuming wood.

Treatment Types

Treatment can involve a combination of one or two effective methods. Raking the nest down repeatedly and apply diazin granules will not kill the entire colony but with ongoing care, the ants will often relocate. Setting bait traps in areas where the ants often go will encourage the ants to take the toxic bait back to the nest. Widespread bait broadcasting using a seed broadcaster in the lawn helps to control fire ants because they do not forage along a known path, but randomly throughout the lawn.

Ongoing Treatment Benefits

Repeated treatments will eliminate as many members of the ant colony as possible. The lower ant colony population will cause the ants to eventually move their mound to a new location to save the remaining members of the ant colony. Killing the queen using baits and insecticides will cause the entire colony to perish over time. Whenever ants begin to feel threatened or that their colony numbers are significantly decreasing, the insects will move on to a new location, hopefully out of the lawn area, in self preservation.

Treatment Effects

Both abamectin B and fenoxycarb broadcast baits and bait boxes work by rendering the queen sterile and unable to produce eggs so the colony eventually dies out. Control is often slow and takes up to 10 weeks. Spreading boric acid also helps to kill individual ants, which weakens the overall colony. Insecticidal mound drenches and granules, such as diazin-based insecticides, work by killing individual colony members.

Treatment Considerations

Research the ant species that is infesting the lawn when deciding on a course of treatment. Fire ant nests are often hard to locate and wide-ranging, so broadcast bait methods work well to kill them. Typical black ants produce small mounds and forage close to their nest, so focused destruction of the nest mound works to control them over time. Pavement ants enjoy building their nest along walkways or foundations. Placing bait boxes in their pathways significantly reduce their colony numbers and cause the ants to relocate.


Keep all children and pets away from any area treated with insecticides or ant bait. Bait houses pose a danger to both children and pets. When using any type of bait, always apply it on a dry day. Ants ignore wet bait and will simply pass it by during their foraging. Apply bait during the ants' foraging time for best results. Ants are the most active gathering food in the early evening when the temperatures range between 70 to 90 degrees F.


About the Author


Based in Oregon, Kimberly Sharpe has been a writer since 2006. She writes for numerous online publications. Her writing has a strong focus on home improvement, gardening, parenting, pets and travel. She has traveled extensively to such places as India and Sri Lanka to widen and enhance her writing and knowledge base.