Argentine ants are native to the Paraná River drainage basin that runs through Brazil, Paraguay, Uruguay, and Argentina in South America. In the United States, they've become a nuisance across the southern U.S., from North Carolina to California. Cold temperatures and dry conditions limit their range, so they're more common in coastal areas than inland.

They're often confused with odorous house ants. Odorous house ants are typically more robust, and their single node is flattened and hidden by the gaster. Argentine ants look more slender, and their single node stands upright and is easier to see.

What makes Argentine ants especially challenging is how their colonies behave. They show low aggression toward other colonies of their own species, so colonies can merge into supercolonies that spread across multiple properties. They also reproduce by budding, where mated queens and a group of workers break off and establish new nest sites.

Their foraging trails can be several ants wide. You may even see queens moving with the flow of workers. With heavy trails, you can't rely on an insecticide residual alone. Traffic can reduce how long it holds up. Instead, treat the trailing workers directly with a non-repellent insecticide like Sumari, and follow the trail back to nest sites so you can treat where the colony is actually living.

Argentine ants tend scales and aphids on plants for honeydew. Foliar applications of Sumari to non-blooming plants can help remove that food source and increase pressure on the population.

To strengthen the program, use DominAnt Bait Stations to recruit workers and build stronger trails. Leave a few with customers for between-visit activity—so they can respond quickly if ants show up again and you can reduce callbacks.

Argentine ants often use wall voids to invade structures or to nest. PT Phantom II Pressurized Insecticide is a non-repellent aerosol that's easy to apply to voids and reduces the risk of budding associated with repellent products.

Here's the takeaway. Close out Argentine ant accounts with a simple three-part plan: (1) target the active trails and work back to nest sites using a non-repellent product, (2) increase pressure by removing scale and aphid honeydew sources on non-blooming plants, and (3) supplement management with strategic bait placements and wall-void treatments. Build this plan into your service routine, and you'll put consistent pressure on the colony while cutting down on callbacks.