Field Ants

Formica spp.

field ant

Adult field ant; depression in thorax (April Nobile,

field ant workers

Field ant workers (David Cappaert, Michigan State University,

field ant mound

Field ant mound (Steven Katovich, USDA Forest Service,


  • black or reddish brown and black
  • one node (bump between middle and rear body sections)
  • most common ant found in yards and gardens
  • often mistaken for carpenter ants, but not as likely to forage indoors (observed indoors most commonly in spring)
  • ants of multiple sizes
  • depression in thorax differentiates them from carpenter ants

Nesting Habits

  • nest outdoors in loose soil
  • may produce mounds (sometimes incorporating twigs, dried leaves and other plant materials) in exposed areas or nest under rocks, logs, etc.
  • do not frequently come indoors


  • variety of foods
  • prefer sweet materials such as honeydew excreted by aphids and other insects
  • can be scavengers or predators


  • become a nuisance during swarming flights
  • can create mounds in turf areas

IPM Recommendations

  • Seal potential ant entryways.
  • Store food in airtight containers and dispose of trash regularly.
  • Locate and destroy nests in lawns and adjacent areas.
  • Control soft scale, mealybug or aphid populations on nearby ornamental plants.

Additional Resources:

IPM for Ants: Integrated Pest Management in Sensitive Environments (University of Nebraska-Lincoln Extension)