Red Imported Fire Ant Control in San Antonio, TX
Plenty of San Antonio homeowners meet fire ants the morning after a downpour: a fresh hump of loose, crumbly soil in the yard, and a swarm of small reddish ants pouring out the second a shoe touches it. The right first move is not to kick it or flood it, but to bait the whole yard and then deal with the few mounds that sit where people walk. Call or text (210) 281-1064 or book online if you'd rather have a technician handle it.
Why do mounds show up everywhere after a storm? #
The National Weather Service describes South Central Texas as an area people commonly call Flash Flood Alley (NWS Austin/San Antonio). Heavy rain soaks the ground fast, and fire ants answer by rebuilding upward. Texas A&M's Fire Ant Project says a mound of worked soil stands out most right after a heavy rain, which is why a yard that looked clean before a storm can sprout new bumps right after it.
Water also pushes ants indoors: AgriLife notes that whole colonies may move inside during floods. In a city that once logged 11.26 inches of rain at the airport on one October day in 1998, it pays to check the garage, AC unit and slab edges after a big storm.
Fire ants and the caves under the north side #
The north and northwest parts of the county sit over karst, the cave-riddled limestone of the Edwards Aquifer. The U.S. Fish and Wildlife Service lists nine endangered cave invertebrates living in caves on that side of the county, and names non-native fire ants, along with pesticides, among the threats to them (USFWS).
That is a good reason to treat on purpose rather than by habit. SAWS reports that under 3 percent of the recharge zone lies inside city limits, so most homes are not on it, but the principle holds: bait where ants forage, treat only problem mounds, and keep products out of drains and open rock.
Is it really a fire ant mound? #
- Workers of mixed sizes in one mound, about 1/16 to 3/16 inch, reddish brown.
- No hole at the top. Fire ant mounds are fluffy soil with no center opening; ants come and go through tunnels underneath.
- They climb. Disturbed workers race straight up grass blades, sticks and ankles, which few native ants do.
- Native fire ants exist in Texas too, but AgriLife describes them as less aggressive.
Timing the bait #
AgriLife's L-5070 gives May through September as the baiting window for most of Texas, with evening baiting when the soil tops 90 °F. The Fire Ant Project adds a fall broadcast between late August and mid-October.
What to do now, and what to skip #
Do:
- Use the Two-Step Method: broadcast fresh bait across the yard when the grass is dry and no rain is expected for a day or two, then treat individual mounds that sit in high-traffic spots (Two-Step Method).
- Test first: set a little bait out and make sure ants pick it up within about half an hour.
- Expect it to take weeks, even a couple of months, to reach the 80 to 90 percent control AgriLife describes.
Skip:
- Grits, coffee grounds, club soda, cinnamon and molasses. Texas A&M tested home remedies like these and found no documented control.
- Boiling water near plants you like. About three gallons kills roughly 60 percent of mounds, and it kills the grass and plants it touches too.
- Spraying into an AC unit or electrical box. Shut off the power and call a licensed professional or an electrician.
A white pustule a day or two after a sting is normal and can last a week or more; keep it clean, because it infects easily. Chest pain, heavy sweating, nausea, slurred speech, serious swelling or trouble breathing means go to an emergency facility right away.
How Pest Trappers handles fire ants around San Antonio homes #
A technician walks the yard, foundation, AC pad and utility boxes, notes mounds and foraging trails, and asks whether anyone at home is allergic to stings. The Two-Step approach may not suit a home with a highly allergic person, so the technician explains the options for your property and applies any product exactly as its label directs. Treating fire ants around the house is general pest work under our license as Pest Trappers LLC (TPCL #0887549); we do not offer turf or ornamental services. Pricing comes after the inspection.
One rule worth knowing: Bexar is one of the counties under the state's fire ant quarantine (TDA quarantine map), so shipping soil, sod, rooted plants or used dirt-moving equipment out of the quarantined area needs a certificate or permit. More on the insect is in the fire ant guide; everything else we treat in town is on the San Antonio service page. For the other ground-level pest people find around the yard, see scorpion control.