Argentine Ants Identification Guide
Quick Facts About Argentine Ants
Argentine ants are an invasive species from South America, established in parts of Tennessee. Individually they’re small and unremarkable, but their colonies are enormous, with many queens and nests linked into huge networks, which makes them persistent invaders.- Size: About 1/16 to 1/8 inch
- Color: Light to dark brown, fairly shiny
- Body: One node at the waist
- Smell: Faint musty odor when crushed, not the coconut smell of odorous house ants
- Trails: Wide, busy trails, often five or more ants across, running up walls and trees
- Diet: Sweets, especially honeydew from aphids and other plant pests
What Do Argentine Ants Look Like?
Their trails are usually the best clue: thick, steady lines of ants that go on for yards.Argentine Ants vs. Odorous House Ants
Odorous house ants are darker and smell like rotten coconut when crushed. Argentine ants are lighter brown with only a faint musty smell, and their trails are wider and busier. See our odorous house ant guide.
Why Argentine Ants Are Hard to Control
Neighboring Argentine ant nests cooperate rather than fight, forming supercolonies that can cover whole neighborhoods. Each nest has many queens, so killing one nest barely makes a dent, and repellent sprays scatter them and trigger new nests. They also protect aphids, scale insects, and mealybugs for their honeydew, which can lead to more damage on landscape plants.
Signs and Where They Nest
- Trails: Wide, continuous lines along foundations, fences, tree trunks, and into the house
- Indoor activity: Kitchens and bathrooms, especially during hot, dry, or very wet weather
- Outdoor nests: Shallow nests in moist soil, under mulch, stones, boards, and potted plants
- Plant pests: Aphids or mealybugs on plants, with ants tending them
Health & Property Risks
Argentine ants don’t sting and rarely bite. They contaminate food, and by protecting sap-sucking insects they can harm landscape plants.
How to Get Rid of Argentine Ants
- Bait, don’t spray: Use sweet liquid baits along trails, and plenty of them; colonies are huge.
- Treat outside: Most nests are outdoors, so focus on the foundation perimeter and trails.
- Control plant pests: Reducing aphids and scale removes a major food source.
- Cut off access: Trim plants touching the house and seal entry points.
- Reduce moisture: Fix irrigation leaks and pull mulch back from the foundation.
Because of their colony size, Argentine ants often need ongoing professional treatment with non-repellent perimeter products and baits. See our ant control services.
Frequently Asked Questions
How do I know if I have Argentine ants?
Look for small, light-to-dark brown ants moving in wide, busy trails, often up walls and trees. Unlike odorous house ants, they don’t smell like coconut when crushed.
Why are Argentine ants so hard to get rid of?
Their nests have many queens and cooperate as huge supercolonies, so treating one nest barely affects the population, and sprays scatter them.
Are Argentine ants in Tennessee?
Yes, they’re established in parts of Tennessee.
What attracts Argentine ants?
Sweets and moisture, especially honeydew from aphids and other plant pests.
Do Argentine ants bite or sting?
They don’t sting and rarely bite. They’re mainly a nuisance and can contaminate food.
