Ant mounds appearing all over your lawn and sidewalks in colder weather are the result of ants adapting to temperature changes. Here’s why this happens:

  1. Seeking Warmth
  • Colder Temperatures: As the ground cools, ants dig deeper into the soil to escape the cold. In doing so, they create more visible mounds as they bring soil to the surface.
  • Sun-Exposed Areas: Sidewalks, driveways, and areas near buildings often retain heat from the sun, making these locations ideal for ants to establish colonies or migrate.
  1. Soil Moisture and Protection
  • Rain and Cold Weather: Wet or compacted soil due to seasonal rains or cold weather encourages ants to relocate and build mounds in drier, well-drained areas, such as lawns and sidewalks.
  • Flooding: If their existing nests flood, ants are forced to move and rebuild.
  1. Colony Maintenance
  • Seasonal Nest Expansion: Many ant species build or repair their colonies before winter fully sets in, especially in areas with fluctuating temperatures.
  • Food Storage: Ants may increase their activity to gather and store food for the winter, leading to more noticeable mounds.
  1. Species-Specific Behavior
  • Fire Ants: Common in Florida, fire ants are particularly active in cooler weather. They move to higher ground (like lawns or sidewalks) to keep their colonies dry and warm.
  • Other Ground-Dwelling Ants: Many ground-dwelling species like pavement ants create mounds near sidewalks or driveways for access to heat-retaining areas.

How to Manage Ant Mounds:

  • Targeted Treatment:
    • Use a bait product labeled for ants to target the colony.
    • For fire ants, apply a fire ant-specific bait (e.g., hydramethylnon or indoxacarb) around the mounds.
  • Direct Application:
    • Use a granular or liquid insecticide for immediate treatment of mounds. Products containing bifenthrin or permethrin work well.
  • Improve Lawn Health:
    • Keep your lawn well-aerated and minimize excess moisture, which attracts ants.
    • Mow at the recommended height to reduce thatch buildup, which ants can use for shelter.
  • Seal Entry Points:
    • Prevent ants from moving indoors by sealing cracks in sidewalks, driveways, and foundations.