Fireants: Biology, Products, Elimination

For every person (layman or professional) you talk to about the elimination or control of fireants, you will hear a different opinion on what products to use and what methods to employ in your ant control program.  This article will address the different issues: baits, granular insecticides, spray insecticides, various active ingredients, methods of applying each type of pest control product -- and even debunk a couple of old wives tales!

On this page you will find links to different products and topics concerning fireants (or fire ants, if you prefer) as well as other species of household ant pests:

Fire Ant Biology

Fire ants do not bite; they sting like wasps and bees.  They hold on with their mouthparts and inject venom into skin through a smooth - not barbed - stinger.

Imported fire ants are 1/8 to 1/4 inch in length and are reddish brown to black.  They are social insects and live in colonies which may have up to 200,000 individuals.  Fire ant colonies are made up of a queen ant, winged males and females (virgin queens), workers, and brood (which is made up of ant eggs, larvae, and pupae).  The queen fire ant lives in a protected nest which may be several feet deep and can be several feet away from the visible mound or mounds.  There may be several satellite nests near the main nest and some nests may have more than one queen.  
Fire ants usually have two flying swarms each year when winged males and females leave the colony for their reproductive flights.  This insures the spread and survival of the species.  Swarming usually occurs in late Spring and in Summer but can occur during any time of the year.  The number of swarms (and the number of swarmers) can depend on the size, strength and health of the colony as well as contributing conditions: abundance of food sources, rainfall, air and ground temperatures.  After mating the fertilized queen begins a new colony in the soil.  Not every mated queen is successful.  Flying ants (swarmers) have many enemies: birds, lizards, frogs and other bugs -- even other ants.
Over the last few decades, fireants have shown us that they can readily adapt to different weather patterns, locations and even complicated control measures targeting their extinction.  Past attempts at eliminating fireants from certain areas (with the use of massive pesticide treatments from ground and air) have done little to inhibit the tremendous march of these persistent pests.  Most of these programs actually helped the Fireant by wiping out other species of ants that competed with the Fireant for food!
There was a time when entomologists told us that only a few colonies of these biting pests could survive per acre.  It was believed that the different ant colonies would drive out all competing fireants for territory and food. We were also told that each colony would have only one viable queen.  You may know travel through the southeast United States and find dozens of colonies per acre.  Each colony may contain several viable queens and each colony may even share resources with its neighbors.  This social behavior resembles the satellites of other ant pests such as the white-footed ant, pharaoh ant and carpenter ant.
During a trip to the mountains of north Alabama during icy weather, the author noted conical shaped piles of dirt & clay (the soils indigenous to the region) that averaged 3 feet in height, less than a foot in diameter at the base, tapering to a dull point at its top.  When broken (during the middle of the day) these mounds were found to house thousands of worker fireants tending hundreds of ant larvae.  The ants were building mounds which obviously took advantage of the mid-day heat to help incubate and maintain the ant larvae of the colony!  When these same type of mounds were broken open for inspection at sundown, no sign of ant or ant larvae were to be found.  The ants had returned underground to avoid night time temperatures.  Their adaptation to the icy temperatures was a sight to see, but this adaptation is also their undoing: the method might work in northern Alabama and Tennessee but will not work in northern states, due to the frost line.  We might see imported fireants continue to migrate northward but do not expect them to become a major pest above Maryland.

Fire Ant Baits

How Ant Baits Work                Ant Baits Used by Professionals

How to Properly Use Baits for Fireants, Ants

Over the years, there have been numerous attempts to develop the perfect fireant bait and every year the industry gets closer to its goal.  Any bait designed to kill fireants (or other ant pests) must contain the perfect mixture of a carrier, attractants and a killing agent or insecticide.  (An exception is Extinguish Fireant Bait which uses an IGR instead of an insecticide.)  This killing agent cannot be too strong.  If the worker ants detect an insecticide in their food (bait) the food will be rejected by the entire colony.  This detection could happen at different "check points" in the processing of an ant colony's food.  Worker ants cannot eat solid foods (debunking the myth of Kill Ants with Grits) but they can drink liquids and carry solids back to the ant colony nursery.  Ant larvae can digest solids.  These solids are given back to workers (by regurgitating liquids) who (in turn) feed 10 or more other workers, who feed other workers -- eventually reaching the queen (or queens) and their workers.  If a dangerous material (poisons, pesticides, etc.) are detected early enough in this chain of colony digestion of food, the contaminated food is earmarked by the entire colony.  If "food source A" is found to be dangerous, the alarm goes out through the entire colony: "Do not eat food source A!"  In this manner, the colony is protected.
As you can see, there is a delicate balance of insecticide and proper attractants in an ant bait.  Too much insecticide will be rejected; too little insecticide will not be strong enough to penetrate to the inner workings of the ant colony.
There are several professional ant baits being used by pest control operators, golf courses and homeowners.
The most popular (click on links for detailed information on each product):
Ascend Fire Ant Bait    Extinguish Fire Ant Bait
Maxforce Fireant Bait    Maxforce Granular Bait    Niban Granular Bait

Each fireant bait has its advantages, whether it be its mode of action, areas where it may be used or simply affordability for each situation.  This section summarizes each ant bait listed:
Ascend Fire Ant Bait is a bait preferred by those who need to broadcast bait over a large area but are on a more limited budget.  When properly broadcasting a large area for control or prevention of ants, following label instructions might be quite expensive when covering several acres.
Extinguish Fire Ant Bait is a bait that may be used in graze lands and pastures.  Its active ingredient (Methoprene) is not actually an insecticide, but an IGR which inhibits the reproduction of the queen and growth of immature ants, thus breaking the life cycle of the ant colony.  This is a very slow acting product that can take 6 weeks to effectively destroy a colony.

Fipronil first came to the public's attention with the introduction of Frontline Topspot and Frontline Spray for the control of fleas on dogs and cats.  The most popular Fipronil product (at the time of this writing) is a Maxforce FC roach bait gel.  (Maxforce FC has made elimination of cockroach populations easier and more effective than any other bait in the world.)  Next introduced was Termidor, a termiticide that is showing great promise for the control of termite problems in homes and other structures.  In early 2002, Over'n Out! fireant granules began taking its share of fireant control products.  More about this new granule in our discussion on broadcast insecticides.

How to Properly Use Baits for Fireants, Ants

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The most common mistakes in baiting for outdoor ant infestations:

• Not choosing correct pest control products
• Stressing the colony
• Bait contamination
• Watering bait
• Timing
• Patience

Far too many individuals assume that any "Fireant elimination product" is a bait.  Read the label before you buy!  There is a huge difference between an ant bait and an insecticide labeled for treating ant mounds or broadcasting lawns for ants and other insect pests.  Acephate is (a common product purchased for treating ant mounds) is an example of a contact insecticide, not a bait.
Most baits used in the control of ants will list several ant species targeted by the material while others list only fireants or Imported Fireants as the target pests.  As pest management technology improves, baits are becoming more sophisticated.  In outdoor ant extermination the granular bait particles are being designed to be more attractive and of a more convenient size for different species of ants.  This can be seen in Maxforce Fireant Bait, Maxforce FG, Niban FG and Extinguish Fire Ant Bait.  Attractants, killing agent (material used to eliminate the target pest) and carrier sizes are constantly being studied and improved upon.
Do not contaminate your bait!  An ant bait must be attractive (not repellent) to the ant colony.  Bait contamination can occur in different ways.  Storage of material is important, not only by the consumer but also by the distributors and sellers of the product.  Never store your insect baits in an area close to contact insecticides or any material that has strong odors.
Baits are also contaminated when used in conjunction with applications of contact insecticide sprays or granules.  Use your bait as a stand alone product.  There are times to use contact materials and times to use baits but not at the same time.  Besides contaminating the bait (making it unattractive to the pest) you also kill the messenger.  The foraging worker ants should be allowed to carry the bait back to the colony where it can be transferred to all colony members.  In this manner you will achieve total colony elimination.
Ant baits do not need watering to activate or disperse their active ingredients.  Ants will more likely to accept baits in their dry, original form.

Timing is important when implementing a fireant management program.  Most professionals encourage a spring, summer and fall application of baits.  In spring and summer, broadcast entire area with ant bait.  Amount of bait used can vary with the product you choose but generally one to two pounds of bait per acre is required.  In the summer months, spot treating of any remaining or reoccurring mounds is recommended.  When spot treating, avoid the practice of covering the mound with baits.  You will have better bait acceptance by baiting the area immediately around the visible ant mound and by scattering the bait in areas where ants are seen foraging for food.
Patience is a key ingredient in a baiting program.  Ant baits work slowly, so as not to alarm the colony of the pesticide's presence.  Do not expect total colony elimination in the first 6 to 8 weeks after application.  You may see a drastic reduction in worker ants in the first couple of weeks but the colony is still very much alive.  Give your bait a chance to work!

Broadcast Insecticides

Fire Ant Elimination Kits    Top of Page

Unless the cost is too great, broadcasting insecticides over an ant infested area produces better results than spot treating or mound treating with a contact insecticide.  When treating for Imported Fireants, both broadcast and a particular type of spot treatment (mound drenching) is often used.

You may use a granular formulation (Talstar, DeltaGard, Over'n Out!) or liquid concentrate formulation (Talstar Concentrate, Cynoff EC, Dragnet) when broadcasting an ant infested area.  Both formulations will work but there are advantages and disadvantages for both.  Granular insecticides must be watered to move the active ingredients into the soil where they kill foraging ants and other insects.  This is a two step procedure: spread the granules (evenly) and water the granules.  Concentrated insecticide applications are made in one step: spray the area using your hose-end sprayer.
Many people will choose granular products if they are treating a large area where a water source is not available or dragging around a water hose with a hose-end sprayer is not an option.  In this case, you will depend on rainfall to water the granular product.  If there is no rain for several days, sunlight will break down the insecticide, making it far less effective.

Spot Treatment Insecticides

Fire Ant Elimination Kits     Top of Page

Treating individual mounds can be done with a professional ant bait or with contact insecticides:

• When using your bait, distribute the granular material around the mound (not on the mound!) in areas where foraging worker ants are most likely to find the bait.  Dumping bait directly on the mounds will stress the colony; ants within the colony will be more concerned with defending, rebuilding and relocating the mound than gathering foods.  Scatter your ant bait around the mound and the ants should begin to feed in a short time.
• When spot treating mounds with a contact insecticide, use liquid materials instead of granular materials.  With liquid insecticides you can drench the mound with proper volume of product.  A good rule of thumb is to use one gallon of mixed solution per foot of diameter, measuring at the base of the mound.  Best results are achieved using Cypermethrin insecticides or Talstar Concentrate.  Mound drenching works better than merely spraying large mounds.  Spraying large mounds (with a standard pump type garden sprayer) will seal off most of the galleries near the surface of the mound, leaving the majority of the mound intact.  Drenching thoroughly soaks the mound and galleries beneath the soil, giving you a better kill.  If the majority of the worker ants and the nursery come into contact with your pesticide solution, the queen ant has no support and will die.

Fire Ant Elimination Kits        Cypermethrin insecticides        Talstar Concentrate   Pesticides

Over'n Out!    Ascend Fire Ant Bait    Extinguish Fire Ant Bait
Maxforce Fireant Bait    Maxforce Granular Bait    Niban Granular Bait

ant baits        insect baits    Fire Ants