Argentine ants are the ant most Fresno residents know, even if they do not know the name. These small, light-brown ants form enormous supercolonies that can span entire neighborhoods, and they flood kitchens and bathrooms in search of food and water. Irrigated lawns, fruit trees and wooden structures in places like Fig Garden, Old Fig and the Tower District provide everything they need. Ants are active nearly all year in the Valley's mild climate and become worse during hot, dry spells and after winter rains.
PestMinistry is a referral service. We connect callers with independent, licensed ant control providers in our network and do not apply treatments ourselves.
The main ants in Fresno
- Argentine ants are tiny, shiny and light brown, forming trails along walls, pipes and tree trunks.
- Odorous house ants have a distinct coconut-like odor when crushed.
- Carpenter ants nest in damp or damaged wood, including old trees, fence posts and eaves.
- Pavement ants nest beneath slabs and sidewalks.
- Fire ants are not widely established in Fresno, so unusual stinging ants should be identified.
Why Argentine ants are hard to beat
Unlike many ants, Argentine ants live in colonies with many queens and do not compete with neighboring nests. This means that killing visible ants rarely helps; the supercolony simply replaces them. They protect and feed on honeydew from aphids and scale insects on trees and shrubs, which keeps them thriving in landscaped yards. They tend to move indoors during hot, dry spells, as well as during rainy periods when their nests flood. Successful control usually involves slow-acting baits that workers carry back to many queens, and exterior treatments that cut off trails.
What providers do
- Inspect the yard, trees, foundation and interior for trails and entry points.
- Use baits and insecticides suited to the species and season.
- Treat the perimeter and key harborage areas such as mulch and tree bases.
- Remove or manage honeydew-producing insects when possible.
- Advise on trimming, irrigation and sealing gaps.
Expect to see more ants for a few days after bait is placed. Let them feed, because the bait works through the colony.
Where Argentine ants nest
In the Valley, Argentine ants nest in mulch, under stones and pavers, in potted plants, along irrigation lines and in the soil around tree bases. In winter they often shift closer to buildings, taking advantage of warm, dry wall voids, and in summer they move toward water. Checking planters, drip lines and the soil around foundation plantings can show where a trail begins, which makes it easier for a provider to place bait where it counts.
Everyday steps
- Cut tree and shrub branches that touch the house.
- Reduce mulch near the foundation, and avoid overwatering.
- Clean up spills and pet food promptly.
- Seal cracks around windows, doors and pipes.
- Harvest fruit and clear windfalls.
Contact
If ants keep returning, call (844) 725-1661. We will connect you with a licensed provider in our network who serves Fresno.
Fresno ant FAQs
Why does it seem like I kill thousands and they keep coming?
Supercolonies have huge numbers of workers and many queens, so killing visible ants does not reduce the source.
Do ants come inside more in winter?
Often after heavy rain, yes, because nests flood and ants seek dry shelter.
Are carpenter ants a problem in the Valley?
They are less common than Argentine ants but occur where wood is damp, and they can damage structures.
Can I use homemade solutions?
They may deter some ants temporarily, but they rarely stop a supercolony.