How to control household ants?


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 pesticides safely!

  • Wear protective clothing and safety devices as recommended on the label. Bathe or shower after each use.
  • Read the pesticide label—even if you’ve used the pesticide before. Follow closely the instructions on the label (and any other directions you have).
  • Be cautious when you apply pesticides. Know your legal responsibility as a pesticide applicator. You may be liable for injury or damage resulting from pesticide use.

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