The two-step fire ant method, explained for homeowners

The Two-Step Method is Texas A&M AgriLife's approach to managing red imported fire ants across a whole yard. Step one is broadcasting a fire ant bait over the entire area once or twice a year; step two is treating only the individual mounds that sit where people walk, play or work. It works slowly but broadly, and Texas A&M reports it can bring about an 80 to 90 percent reduction in mounds.

Know the suspect: why are fire ants so hard to beat?

Red imported fire ants aren't native. They came from South America, arrived in Mobile, Alabama, around the 1930s and reached Texas in the 1950s, then spread steadily across the state. Today they are found across much of Dallas-Fort Worth.

The trouble with treating mounds one at a time is that you only see some of the colonies. Texas A&M's fire ant FAQ notes that treated areas get reinfested, with new colonies likely appearing after the next rain, and certainly within a year. The Two-Step Method goes after the colonies you can't see as well as the ones you can.

See the red imported fire ant profile for identification tips.

What is the Two-Step Method?

According to Texas A&M's Two-Step Method page:

1. Step one: broadcast bait over the entire yard.
2. Step two: treat individual mounds that are a problem, such as those near sidewalks, play areas, gardens or doorways.

Texas A&M says the method works best in heavily infested areas, which it describes as five or more mounds per quarter acre. The FAQ notes that it fits larger residential areas best, and AgriLife has promoted neighborhood-wide programs because fire ants don't respect property lines.

How does step one, broadcast baiting, work?

Fire ant baits are made of pesticide on processed corn grits coated with soybean oil. Worker ants pick up the bait and carry it back to the colony, where it is shared and affects the queen's ability to reproduce or survive. Because the ants do the delivery, baits reach colonies you never find.

When should you broadcast fire ant bait in North Texas?

Timing matters more than almost anything else, because ants have to be out foraging to pick the bait up.

• Fall is the preferred window. Texas A&M recommends baiting from late August to mid-October. The FAQ adds that fall applications pay off because mound numbers will already be suppressed by early spring.
• Spring is the second window, but North Texas waits. Texas A&M has advised that homeowners in north central Texas may need to wait a few weeks longer than Central and South Texas, because cooler soil delays foraging. Its school IPM program has suggested holding off until May.
• Watch soil temperature. Fire ants usually forage once soil is around 70°F at a 1-inch depth. Texas A&M's North Texas guidance describes a best range of roughly 70 to 95°F at that depth, with May through September as the main season in North Texas.
• Pick the time of day. In hot months, apply in the late afternoon or evening. Summer morning applications leave the bait sitting in heat and sun before the ants come out.

What conditions do you need for bait to work?

Texas A&M's checklist for a good bait application:

1. Dry ground and grass, with no rain expected for 24 to 48 hours.
2. Fresh bait. Use bait from an unopened or recently opened container. Texas A&M suggests discarding opened bait that is more than a few months old.
3. Ants actively foraging. Test first: put a small amount of bait near a mound. If ants pick it up and carry it underground within a few minutes, the bait is fresh and conditions are right. The FAQ allows 45 to 60 minutes for the test.
4. Follow the label rate and spreader setting. Use the rate and spreader setting the label gives, no more.

How long does fire ant bait take to work?

Be patient. Texas A&M says baits are slow-acting and can take weeks to months to reach 80 to 90 percent control. Speed depends on the active ingredient. Ingredients you may encounter on bait labels include indoxacarb, spinosad and hydramethylnon. Texas A&M reports that baits with these ingredients typically show results in two to four weeks, while baits with other ingredients, such as insect growth regulators, may take two to six months but can suppress ants for longer.

How does step two, mound treatment, work?

Step two handles the mounds you can't wait on. Texas A&M lists several individual mound treatment options:

• Liquid drenches can eliminate mounds within hours and leave minimal residue.
• Granules are sprinkled on and around the mound and then watered in, usually with 1 to 2 gallons of water.
• Dusts act quickly but leave residue on the surface.
• Baits can also be applied around a single mound.

Texas A&M notes that most products applied directly to a mound kill the colony in one to two days. The FAQ advises against mound treatments during hot, dry conditions, when ants move deeper underground.

What about hot water and home remedies?

Texas A&M says that pouring 2 to 3 gallons of very hot or boiling water on a mound kills the ants about 60 percent of the time, but it also kills surrounding plants, may only push the colony elsewhere, and carries a real risk of scald burns. Instant grits don't work: the FAQ explains that worker ants cannot ingest particles larger than 2 microns.

Ride the trail: a homeowner's Two-Step checklist

1. Map the yard. After a rain, walk the property and count mounds. Note which ones sit in high-traffic spots.
2. Check the calendar and the forecast. Aim for fall, or late spring in North Texas, on a dry stretch with no rain expected for a day or two.
3. Read the whole label before buying. The label is the law: the site, rate, equipment and safety directions are legal requirements, not suggestions. Our guide on how to read a pesticide label breaks it down.
4. Run the foraging test. Confirm ants are picking up the bait before you treat the whole yard.
5. Broadcast in the evening. Use a hand-held or push spreader set to the label's rate.
6. Treat problem mounds. Use step two only on mounds that put people or pets at risk.
7. Keep kids and pets off treated areas for as long as the label directs, and store leftover bait sealed and out of reach.
8. Repeat once or twice a year. Rebait when new mounds start to show.

Talking with neighbors about baiting around the same time can slow reinfestation from next door. For the full seasonal picture, see our DFW pest seasons guide and integrated pest management at home.

What should you do about fire ant stings?

Fire ant stings burn and itch, and Texas A&M notes that a white pustule usually forms within a day or two. Wear shoes or boots and tuck pants into socks when working near mounds.

Some people develop serious allergic reactions. Texas A&M advises getting immediate medical attention for chest pain, nausea, severe sweating, trouble breathing, serious swelling or slurred speech. Call 911 in an emergency, and call Poison Control at 1-800-222-1222 for questions about stings or a pesticide exposure. Anyone with a history of strong reactions should talk with a doctor.

When to get help

Consider a licensed pest professional for large properties, sensitive sites, or yards that stay heavily infested after a full season of the Two-Step Method. In Texas, structural pest control licenses are issued by the Texas Department of Agriculture's Structural Pest Control Service. Texas A&M's fire ant site also offers fact sheets for deeper reading.

This field guide is educational and does not offer treatment bookings.