Ant Bites and Flying Ants in Los Angeles: What They Mean

The Argentine ant, which UC IPM calls the most common ant in and around California homes, is not one of the state's few stinging species. The ants that hurt most here are fire ants. The native southern fire ant lives here; the red imported fire ant is established toward Orange County and the Inland Empire. Flying ants are mating swarms, not a new species, and people confuse them with termite swarmers.

Which ants in Los Angeles bite or sting?

Fire ants and harvester ants sting. Velvety tree ants and carpenter ants bite. Most other species, UC IPM says, rarely do either.

Red imported fire ant. UC IPM reports it has infested Los Angeles, Orange, Riverside, San Bernardino and San Diego counties. The mound is often dome-shaped, and the ants quickly climb onto and sting anything that touches it.
Southern fire ant. Per UC IPM, the native fire ant nests in small mounds with flattened, irregular craters, in wood or under rocks. It stings, but the imported species is much more aggressive when a nest is disturbed.
Harvester ants. UC IPM groups them with native fire ants as the most common stinging ants in California, primarily outdoors.
Velvety tree ant. It nests in trees and dead wood such as old limbs, stumps and logs; UC IPM calls it an aggressive biter.
Carpenter ants. They cannot sting, but UC IPM says they inflict painful bites with their powerful jaws and spray formic acid into the wound.
Argentine ants. Not on UC IPM's list of stinging ants. If you have itchy welts and see only Argentine trails, look at fleas or bed bugs first.

What should you do right after a fire ant sting?

Get the ants off fast, keep the stings clean, and leave the pustules alone.

Rub the ants off briskly. NIOSH notes they attach to the skin with their jaws, so a light brush is not enough.
Wash the stings with soap and water. UC IPM warns that the pustules can become infected if they are not kept clean.
An oral antihistamine may help with itching. NIOSH says to follow the package directions, since drowsiness may occur.
Expect burning and itching, then a white, fluid-filled pustule within a day or two. Do not scratch or open it.

When does an ant sting need a doctor?

NIOSH says to get to an emergency medical facility immediately after fire ant stings if the person has:

Severe chest pain
Nausea
Severe sweating
Loss of breath
Serious swelling
Slurred speech

UC IPM adds dizziness and shock, and notes that a small percentage of people are allergic to the stings. NIOSH advises anyone with a history of severe allergic reactions to insect bites or stings to carry an EpiPen and wear medical identification. See a doctor if a pustule looks infected; UC IPM warns that infected pustules may leave permanent scars.

Are flying ants a different kind of ant?

No. Flying ants are the winged males and females of an ordinary colony. UC IPM explains that they leave the nest in large numbers in warm weather to mate, then lose their wings soon after. That is why you find wings on a sill and no insects.

Argentine ants are the exception. UC IPM notes that their newly mated queens are accompanied by workers when they disperse to found new colonies, and the colonies link into one supercolony. A dense cloud of flying ants at an LA home is more likely carpenter ants, fire ants or termites.

How do you tell a flying ant from a termite swarmer?

Check the waist, the antennae and the wings. UC IPM's three tests work from a sharp phone photo:

Waist. An ant's body is constricted, so it looks like it has a thin waist. A termite has a broad waist.
Antennae. Winged female and worker ants have elbowed antennae. Termite antennae are not elbowed.
Wings. An ant's hind wings are smaller than its front wings. A termite's front and hind wings are about the same size.

Catch a few on clear tape before you vacuum.

What does a swarm inside your house mean?

It depends on the insect and where it came out.

A few winged ants at windows or lights. They most likely flew in from a mating flight outside. Vacuum them and check the screens.
Winged ants pouring from a wall, baseboard or window frame. A colony is nesting in the structure. UC IPM lists hollow doors and window frames among carpenter ant nest sites. It notes that an indoor nest is usually a satellite of a larger parent nest outside, in a tree, woodpile or landscaping materials. Our ant control service targets that parent colony; our guide to eliminating the colony, not just the trail explains why.
Termite swarmers emerging indoors. UC IPM notes that a swarm does not always mean the building is infested; a professional inspection is usually required to confirm one. It lists thousands of flying insects suddenly appearing in a bathroom or kitchen among the ways infestations are discovered. An inspection by a licensed pest management professional is required before any treatment, per UC IPM. PesPro does not treat termites. Call a termite-specialty company and verify its license with the Structural Pest Control Board.

When do ants and swarms peak in the LA basin?

Ants move indoors when the weather turns extreme in either direction, and swarms follow warm days after a soaking rain.

Late winter and early spring. Colonies are just beginning to grow, and UC IPM says treatments made now are most effective. Carpenter ants take mating flights in spring; one species, C. modoc, swarms in late afternoon, often after heavy rain. A warm, sunny spring day after rain is the optimal time for subterranean termite swarming.
Summer. UC IPM lists refuge from dry, hot weather among the reasons ants enter buildings. Fire ant baits work best when ants are out foraging, at 70 to 90°F, per UC IPM.
Fall and winter. The first soaking rains bring the flooded conditions UC IPM lists as another trigger for indoor invasions. The most common subterranean termites in California, Reticulitermes, swarm in the afternoon in spring or fall on clear days after a soaking rain.

How does PesPro handle stinging and flying ants?

We identify the species first, then treat the colony rather than the trail. Fire ant mounds, Argentine supercolonies and carpenter ant nests each call for a different method.

Ant control comes as a bi-monthly or quarterly general pest control subscription or a one-time targeted treatment. The written quote is free. Same-day service costs an extra fee and depends on the day's route. Every service carries a 30-day guarantee. For ants, a return visit within 30 days costs 30% of the original price; the third visit at no extra cost applies to cockroaches, bed bugs and rodents.

We serve Los Angeles County and San Bernardino County from El Monte, in English and Spanish. Check your service area, request a quote, or call (323) 472-5329.

Frequently asked questions

Do Argentine ants bite people?

Not in a way most people notice. UC IPM says ants can bite with their pincerlike jaws, although most species rarely do. The Argentine ant is not among the stinging ants it names. If you have itchy welts and see only Argentine trails, suspect fleas or bed bugs instead.

Are red imported fire ants in Los Angeles County?

Yes, but unevenly. UC IPM reports the species has infested Los Angeles, Orange, Riverside, San Bernardino and San Diego counties. A 2019 map from a UC Cooperative Extension IPM advisor shows it widespread in Orange and Riverside Counties. It was not established in western and central Los Angeles County. A fire ant sting there is more likely from the native southern fire ant.

Does a swarm of flying ants mean I have termites?

Not by itself. A pinched waist, elbowed antennae and unequal wings mean ants. A broad waist, straight antennae and four wings of about the same size mean termites. If they are termites, call a licensed termite company; PesPro does not treat termites. If they are ants, we find and treat the colony.

Does PesPro treat fire ants?

Yes. Fire ants are among the species covered by our ant control service, along with Argentine ants, carpenter ants and odorous house ants. We target the colony, not just the ants you see, with methods tailored to each species. The written quote is free. Call (323) 472-5329 or request a quote.