Why they come in
Most ants nest outdoors and enter buildings when they find food or water. Utah State University Extension notes that most Utah species are foragers. They find a source, then bring others back to it. Some, like pharaoh ants, can settle in warm, moist places inside walls.
Which ants are they?
USU Extension lists six ants commonly found around Utah buildings: pavement ants, field ants, carpenter ants, harvester ants, pharaoh ants and odorous house ants. Different ants respond to different treatments, so it helps to know what you have. Take a clear photo or tell us where and when you see them.
What draws ants to Southern Utah homes
- Irrigation and watered landscaping near the foundation
- Leaks under sinks, around water heaters and in bathrooms
- Crumbs, sticky spills, pet food and unsealed containers
- Cracks in the foundation and gaps around doors and pipes
- Branches and plants touching the house
Why spraying the ants you see often fails
Marching ants are workers. The colony keeps producing more. USU guidance suggests following trails to the nest when possible and using baits that fit what the ants eat, because ants share food with the colony. A spray that kills what you see can leave the source untouched.
What to do
- Clean up food sources and wipe down trails.
- Fix leaks and reduce moisture.
- Seal cracks and gaps where ants come in.
- Trim plants away from the house.
- If ants keep returning, call for help. See ant control in St. George.
What not to do
- Do not spray the trail and walk away. For some species, repellent sprays can push a colony to spread into new areas.
- Do not leave sweet spills, pet food or crumbs out overnight.
- Do not ignore a moisture problem. Ants keep coming back to water.
Reading the signs
Tiny ants in a line to sugar or grease in the kitchen suggest foragers from an outdoor nest. Large ants inside wood or walls can point to a nest indoors and need a closer look. Piles of sawdust-like debris can also be a sign. Tell us what you see and where.