9/28/04

Fall is the Ideal Season for Treating Red Imported Fire Ants

North Carolinians typically may relate the onset of fall with cooler weather and changing leaves, but fall is also the ideal time to treat red imported fire ants, an invading insect species that has spread into Wake County and the Town of Holly Springs during recent years. The ants form conspicuous mounds and, when the mounds are disturbed, aggressively and repeatedly sting.

How do I know if I have fire ants?

Fire ants are reddish to dark brown, and some fire ants are winged. Although fire ants range in size from 1/8 to 1/3 inch in length, a fire ant’s head width never exceeds its abdomen width.

According to the NC Cooperative Extension Service, fire ant mounds constructed in clay soils are usually symmetrical and dome-shaped; mounds built in sandy soils tend to be irregularly shaped. Mound heights vary depending on the size of the ant colony. Unlike most ant mounds, fire ant mounds have no center opening because the ants leave and enter the colony through underground tunnels.

What do fire ant stings look like, and are they lethal?

Fire ant stings have a burning sensation and form a white, fluid-filled pustule within 24 hours. According to Texas A&M University, s tings are lethal to a very small portion of the people who experience severe allergic reactions. Symptoms of an allergic reaction to a fire ant sting include excessive swelling, itching or redness, or other symptoms such as shortness of breath, thickening of the tongue or sweating, according to the university. If these symptoms occur, seek medical help immediately. Otherwise, keep stings clean and in tact to avoid secondary infections.

Texas A&M University also reports that fire ants first bite with their mandibles in order to anchor for the thrust of the sting. Although the university says that wearing rubber boots and gloves powdered with talc when working in proximity to fire ants can deter the insects, if a pinching sensation is felt, the ants should be swept off skin quickly before they actually sting.

How do I treat fire ants?

Fall is the ideal time to apply fire ant bait insecticides because the fire ant populations will be reduced during winter; mating season is in the spring and summer. Texas A&M University recommends a two-step method for treating fire ants but concedes that no method is entirely effective all the time, and no method is permanent. The two-step method involves baiting a wide area, waiting several days, and then applying treatment directly to individual mounds. Mound-specific treatment types include dust, granule, bait or drench insecticides. Fire ant insecticides can be found at local stores that sell lawn-care products. Always follow label directions when applying fire ant treatments.

An alternative method to insecticide is applying extremely hot water to fire ant mounds, according to the university; approximately three gallons of very hot water (90 F) poured onto mounds will eliminate ants about 60% of the time. The university recommends treating mounds on cool, sunny mornings when the ants are close to the surface. Hot water may damage grass and plants; be careful to avoid burning yourself while applying the treatment.

Town of Holly Springs - PO Box 8 - 128 South Main Street - Holly Springs, NC 27540 - (919) 552-6221 - Holly.Springs@hollyspringsnc.us