Unlike fire ants (Solenopsis spp.), nuisance ants (Family: Formicidae) are not typically pests in managed turfgrass but can become an issue when they are prone to inhabiting the same area from year-to-year.

Formica ants are comprised of three species: Formica integra (red wood ants), Formica subsericea, and Formica exectoides (Allegheny mound ant). F. integra are a red two-tone color, often the abdomen is much darker than the thorax. F. integra feeds on other arthropods like sawfly larvae, bark beetles, termites, honey bees and tends aphids, psyllids and scale insects for honeydew. F. subsericea are all black and also feed and tend to other insects. F. exectoides are red-black ants that are prevalent in the eastern United States.

Formica ants can be pests of open, sunny areas, constructing mounds that can disrupt the turf surface. To keep shade off the mound, ants will severely damage nearby vegetation.

Ants are social insects that construct colonies, or nests, when temperatures are not too hot (spring and fall). Similar to fire ants, formica ants are more prevalent in areas with higher soil temperatures, near sidewalks, concrete slabs, pavement or in areas with direct sunlight and bare soil. A colony generally consists of an egg-laying queen, males, immatures (eggs, larvae and pupae) and sterile, female workers. The queen lays eggs which are tended and fed by worker ants. In the spring and fall, colonies produced winged ants that leave the colony, mate and seek new nesting sites.

Although formica ants do not present a human health hazard like fire ants, they are considered a nuisance pest. Worker ants can infest buildings in large numbers in search of food for the growing colony. The construction of nests results in large mounds, particularly large with F. exectoides, that are unsightly and will often damage mowing equipment.

Cultural Control

Ants serve a useful role in the ecosystem so the presence of ants in turf is not always a negative thing. However, frequent disruption of a mound by digging or flooding with a garden hose may not kill the colony, but could cause the mound to relocate to a less objectionable location. Reducing the amount of available food (pet food, fruit, bird feeders) and eliminating moist wood or debris from an area can help discourage ant colony establishment.

Biological Control

No biological control option

Chemical Control

If chemical control is necessary, carbaryl (Sevin) or pyrethroids can be used for control. For Formica integra located next to a structure, a gel bait containing fipronil may be used. Bait stations should be used in places where pets may have access. If you wish to use a bait, it should be one listed for sweet-loving ants and tested for attractiveness. Fire ant baits will not be attractive to these ants. Aloft™ is a good general nuisance ant product for professionals. For additional chemical choices, see the NC Agricultural Chemicals Manual.

• 2018 Pest Control for Professional Turfgrass Managers. Bowman, D. et al. 2017. NC State Extension Publication AG-408. 81 pp.
• Extension Plant Pathology Publications and Factsheets
• Horticultural Science Publications
• North Carolina Agricultural Chemicals Manual

For assistance with a specific problem, contact your local Cooperative Extension Center