Have fire ant mounds all over your yard? A local pro can treat the entire property safely.
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Fire Ant Sting Stages: What to Expect
| Time After Sting | What Happens | What to Do |
|---|---|---|
| Immediate | Intense burning pain at each sting site. Fire ant venom contains solenopsin, an alkaloid that causes immediate pain and localized cell death. | Move away from the mound. Brush ants off — do NOT slap them. Slapping triggers more stings as a defensive response. |
| 2-6 hours | Red welts form. Itching begins. Swelling around each sting site. | Wash with soap and water. Apply ice pack (10 min on, 10 off). Take oral antihistamine for itching. Do NOT apply topical antihistamine cream — it can irritate the pustules. |
| 24 hours | Characteristic white pustules form at each sting site. These are sterile — filled with dead white blood cells, not bacteria. This is the definitive fire ant sting marker. | Do NOT pop the pustules. Keep clean and dry. Popping introduces bacteria and can cause scarring and secondary infection. The pustule will dry up and heal on its own in 7-10 days. |
| 3-10 days | Pustules dry, crust over, and heal. Mild scarring possible if pustules were disturbed. | Let them heal. If a pustule breaks accidentally, clean with soap and water, apply antibiotic ointment, and cover with a bandage. |
How to Kill a Fire Ant Mound Without Chemicals
Boiling water method (most effective DIY): Bring 2-3 gallons of water to a rolling boil. Pour directly onto the mound — slowly, to let the water penetrate deep. The boiling water kills ants on contact and collapses the tunnels. Success rate: 60-70% on the first pour. A second pour 24 hours later kills any survivors. Do this at dawn or dusk when most ants are inside the mound. Do NOT pour gasoline, diesel, or motor oil on the mound — this contaminates soil and groundwater and is illegal in Texas.
Biological control (prevention): Beneficial nematodes (Steinernema carpocapsae) applied to your lawn will parasitize and kill fire ant queens before they establish new colonies. Apply in spring and fall when soil temperature is above 60F. This is a prevention strategy, not a treatment for existing large mounds.
Sources: Texas A&M AgriLife Extension — Fire Ant Management; Texas Parks & Wildlife Department. This guide is for informational purposes. Seek medical attention for severe reactions.