Oregon State University Extension Service


How to control household ants?

I have an ant problem inside my house. Throughout the year I have ants roaming every room of my house, with periodic outbreaks when they find something to eat.

When there's an outbreak, I use bait to deal with them, but no matter how much I use, there's an infinite supply of ants. I'm sick of constantly having ants everywhere. Can you help me?

It is likely that you have odorous house ants (Tapinoma sessile), as they are the most common house-infesting ants in western Oregon, but it is still worth having them identified because different species require different management tactics. Pavement ants (Tetramorium caespitum) are another common species of ants in the Pacific Northwest.

This site has more information on ant identification: How to Get Rid of Household Ants, Solve Pest Problems

Discouraging ants in your home

Triggers for ant invasions include extremely hot and cold weather conditions and heavy rain, in addition to food residue. Here are some suggestions for discouraging ants:

  • Clean up food residue that attracts ants. This includes crumbs, pet food, and grease on kitchen surfaces.
  • Frequently take out your garbage and recycle bins.
  • Store food in sealed containers with airtight lids.
  • Watch for ants on indoor plants. Ants will be attracted to aphids and other insects that feed on plants.

Check out this web resource for additional tips: What to Do About Insects in Stored Food, Solve Pest Problems

Commercial bait

Ants take the bait back to their nest, which poisons the nest and eliminates the colony. Because you are seeing a lot of activity, it is possible that the ants have established a colony or colonies in or around your house. Here are some tips when using ant baits:

  • Leaving the bait out at all times, not just when the ants are visible. The ants can persist and only become obvious and appear in abundance when they detect food in a conspicuous area.
  • Make sure your bait is for the appropriate ant species. It may be helpful to switch to a different bait that may be more effective against the species in your house.
  • Follow the instructions carefully on any ant baits used. Product labels indicate whether they are for use indoors or outdoors.

Pest control companies

If the bait is still not effective, consider hiring a pest control company as they can apply products safely in and around your home.

The following resource has important considerations for hiring a pest control company: Selecting a pest control company, National Pest Information Center

¡Use los pesticidas con seguridad!

  • Póngase ropa de protección y equipo de seguridad según las recomendaciones de la etiqueta. Báñese después de cada uso.
  • Lea la etiqueta del pesticida—aunque lo haya usado antes. Siga al pie de la letra las indicaciones de la etiqueta (y cualquiera otra indicación que Ud. tenga).
  • Tenga precaución al aplicar los pesticidas. Conozca su responsabilidad legal como aplicador de pesticidas. Usted puede ser responsable de heridas o daños resultantes del uso de un pesticida.

Source URL: https://extension.oregonstate.edu/ask-extension/featured/how-control-household-ants