Managing Imported Fire Ants in Urban Areas (B 1191) University of Georgia Extension Imported fire ants interfere with outdoor activities and harm wildlife throughout the southern U.S. Ant mounds are unsightly and may reduce land values. Although fire ants do prey on flea larvae, chinch bugs, cockroach eggs, ticks and other pests, the problems they cause usually outweigh any benefits in urban areas. While it is not possible to eradicate this species, controlling fire ants is highly desirable. The best control programs use a combination of non-chemical and chemical methods that are effective, economical and least harmful to the environment. 2016-12-20 16:29:14.11 2006-06-02 14:34:42.0 https://secure.caes.uga.edu/extension/publications/images/primary-pub-images/fireantmound.jpg Managing Imported Fire Ants in Urban Areas | Publications | UGA Extension Skip to content

Managing Imported Fire Ants in Urban Areas (B 1191)

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Introduction

The two species of imported fire ants (red imported fire ant, Solenopsis invicta Buren, and black imported fire ant, Solenopsis richteri Forel) and their hybrid are nuisance insects whose stings can cause serious medical problems. Imported fire ants interfere with outdoor activities and harm wildlife throughout the southern United States. Ant mounds are unsightly and may reduce land values. Although fire ants do prey on flea larvae, chinch bugs, cockroach eggs, ticks and other pests, the problems they cause usually outweigh any benefits in urban areas. While it is not possible to eradicate this species (see History of Control Efforts), controlling fire ants is highly desirable. The best control programs use a combination of non-chemical and chemical methods that are effective, economical and least harmful to the environment.

Integrated Pest Management (IPM)

Integrated Pest Management, or IPM, is a systems approach to managing insect, mite, disease and weed pests. It uses a combination of the most compatible and ecologically sound pest suppression tactics to keep pest populations below levels that cause problems. IPM uses cultural, biological and chemical methods. This bulletin describes site-specific, goal-oriented management programs for urban sites where fire ants occur. The goal of IPM is to prevent the problems caused by unacceptably large numbers of fire ants, rather than eliminating all ants from the ecosystem.

USDA Quarantine Program

Because fire ants are easily transported in nursery stock and soil, the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service (USDA, APHIS) developed a quarantine program for this pest in the 1950s. The USDA Imported Fire Ant Quarantine program is administered by state regulatory agencies (e.g., Alabama Department of Agriculture and Industries, Arkansas State Plant Board, Georgia Department of Agriculture, Louisiana Department of Agriculture and Forestry, Oklahoma Department of Agriculture, Tennessee Department of Agriculture, Clemson University Department of Plant Industry, Texas Department of Agriculture). The purpose of the quarantine program is to minimize the spread of imported fire ants by requiring proper inspection and treatment of all nursery stock, turfgrass, hay and other articles shipped out of quarantined areas (Fig. 1). Inspectors also survey non-quarantined counties for fire ants and occasionally treat small, isolated infestations. The public should do its part to avoid spreading the ants by not transporting or purchasing fire ant infested articles.

Figure 1. National quarantine map Figure 1. National quarantine map.
Figure 1a. Georgia quarantine map Figure 1a. Georgia quarantine map.

Management Options

Properly identifying the ant species is the first step in determining whether and how to control them (see Fire Ant Biology and Identification). In the following sections are options for managing various kinds of imported fire ant problems. There may be other effective methods not mentioned. There is rarely a single best method of control.

Note: See Fire Ant Treatment Methods for information about biological control, home remedies, and insecticide products and their proper use. Use only pesticides labeled for the location or “site” you want to treat. For instance, DO NOT use a product in your vegetable garden unless that site is listed on the label.

Home lawns and other ornamental turf

Fire ants commonly infest lawns, school yards, athletic fields, golf courses and parks, where they pose a medical threat to people and animals. Their mounds also detract from the appearance of the landscape and can damage lawn care equipment.

Treatment options

Program 1. The “Two-Step Method”:

This program suppresses ants in ornamental turf and non-agricultural lands, including roadsides. It is also suitable for pasture and rangeland, provided that the products selected are specifically registered for use in these sites. It is best suited to medium-sized or large areas, and the cost is moderate. This approach is not suggested for previously untreated areas with large numbers of native competitor ants and few fire ant mounds (20 per acre or fewer). The goal of this program is to reduce fire ant problems while minimizing the need to treat individual mounds.

The two steps involve: 1) broadcasting a bait product (see section on proper use of baits), followed by; 2) treating nuisance mounds with a faster acting individual mound treatment or with a mound re-treatment of the bait:

1
Hand spreader
Step 1. Once or twice per year, broadcast a bait-formulated insecticide or use an outdoor bait station product as directed on the label. Most conventional baits are applied at a rate of 1 to 1½ pounds of product per acre, although some products are applied at higher rates. Periodic broadcast applications of fire ant baits will suppress ants about 90 percent when properly applied. A bait can be broadcast with hand-held, vehicle-mounted or aerial applicators. The speed and duration of ant suppression differs with the product used. Hydramethylnon and spinosad baits (see Table 1 for trade names) provide maximum control 2 to 4 weeks after application, while insect growth regulator (IGR) bait products (i.e., those containing fenoxycarb, methoprene or pyriproxyfen) provide maximum suppression 2 to 6 months after treatment depending on environmental conditions. Abamectin baits act more slowly than hydramethylnon and spinosad but more quickly than IGR products. Using higher rates of an IGR bait does not eliminate colonies more quickly. For instance, a late summer application produces maximum suppression the following spring. Where there are many mounds per acre (200 or more), a second application may be needed after the maximum effects of the first treatment have occurred, because not all mounds are affected by a single bait application.
2

Step 2. Wait several days or more after applying the bait, and then treat nuisance ant colonies (such as those in sensitive or high traffic areas) using an individual mound treatment method (see Program 2, Step 1, below). Otherwise, be patient and wait for the bait treatment to work. Any nuisance mounds that escaped the effects of the bait treatment, or colonies migrating into treated areas, should be treated as needed. In large areas individual mound treatment may not be feasible and routine broadcast bait treatments alone may provide sufficient control.

Repeat the bait application when ants re-invade the area and mound numbers reach about 20 to 30 per acre. Bait products do not protect against reinvasion by ant colonies from surrounding land or by newly mated queens. Ant populations can fully recover within 12 to 18 months of the last bait treatment. Low-lying, moist and flood-prone areas are more prone to re-infestation.

Program 2. Individual Mound Treatments:

This approach is best used in small areas of ornamental turf (usually 1 acre or less) where there are fewer than 20 to 30 mounds per acre or where preservation of native ants is desired. This program selectively controls fire ants, but rapid re-invasion should be anticipated. It generally requires more labor and monitoring than other programs, and is not suggested for heavily infested areas.

1
Individual mound treatment

Step 1. Treat undesirable fire ant mounds using an individual mound treatment. Products are applied as dusts, granules, granules drenched with water after application, liquid drenches, baits, or aerosol injections. Non-chemical methods such as drenching mounds with very hot water also may be used.

2

Step 2. Continue treating undesirable mounds that appear, as needed.

Program 3. The “Ant Elimination Method”:

This program eliminates nearly all ant species in treated areas. Its effects are more rapid than those of other programs, and it minimizes re-invasion of treated areas as long as the contact insecticide remains effective. However, it is more expensive, uses more insecticide, and has greater environmental impact. This approach is frequently used by commercial applicators.

1

Step 1. (Optional). Broadcast a bait-formulated insecticide in areas where there are many mounds (more than 20 per acre), or individually treat fire ant mounds. Wait 2 to 3 days after applying a bait before conducting the next step.

2

Step 2. Apply a contact insecticide to turfgrass every 4 to 8 weeks, or when ant activity is detected. Liquid or granular products that can be evenly applied to an area are appropriate for this treatment. Some product labels instruct the user to spray “ant hills.” Although initial surface treatment may not eliminate ants located deep in mounds, routine reapplication will eventually eliminate colonies.

Program combinations:

Any of the three programs can be used on specific sites within a managed area where different levels of fire ant control are desired. On golf courses, for instance, Program 3 might be suitable for high use areas such as putting greens and tee boxes. In fairways and rough areas, Program 1 may be sufficient. On athletic fields, fire ants must be eliminated, so Program 3 should be followed. Control programs should be started 6 to 8 weeks before athletic fields will be used. People with severe allergies to fire ant stings should use Program 3 for their lawns or consider using a bait on a calendar schedule.

Homes and buildings

Fire ants from colonies close to homes and other buildings sometimes forage indoors for food and moisture, particularly during the hot, dry, summer months. Entire colonies occasionally nest in wall voids or rafters, or behind large appliances, sometimes moving into buildings during floods or drought. They are a nuisance and can threaten sleeping or bed-ridden individuals and pets.

Treatment options

1

If ants are entering or could enter the home from outdoor colonies, treat mounds near the building using one of the programs described for Home Lawns and Other Ornamental Turf Areas. A contact insecticide with a long residual effect, such as chlorpyrifos, diazinon or a pyrethroid, also can be applied as an outside barrier around the base of the home. Caulking cracks and crevices also may help prevent ants from entering.

2

If fire ants are foraging indoors and do not pose an immediate threat to residents or pets, use a bait labeled for use indoors. Examples are baits containing abamectin (PT 370-Ascend®), hydramethylnon (MaxForce® Granular Insect Bait or Amdro®), or bait stations containing hydramethylnon (MaxForce®, Combat®) or sulfluramid (Raid® Ant Baits Plus). Fire ant baits eliminate the colony. Bait products not specifically registered for imported fire ant control may or may not control them.

3

Follow trails of foraging ants to colonies located indoors and treat them with contact insecticide dusts or sprays (containing bendiocarb, chlorpyrifos, pyrethroids and others) injected into the nest. Treating only ant trails will not eliminate the entire colony and interferes with the use of baits.

4

Vacuum indoor ant trails and dispose of the vacuum bag immediately. Treat the source colony or entry site of the trail using the options above.

Electrical equipment and utility housings

Electrical equipment

Fire ants frequently infest electrical equipment. They chew on insulation and can cause short circuits or interfere with switching mechanisms. Air conditioners, traffic signal boxes, and other devices can be damaged. Fire ants also nest in housings around electrical and utility units. The ants move soil into these structures, which causes corrosion, shorting, and other mechanical problems.

Note: For safety reasons, an electrician or a licensed pest control operator should treat infested electrical equipment. Specialized products and training are necessary to treat these sites safely and effectively.

Treatment program

1

Step 1. Turn off all electrical service before starting. Use an individual mound treatment method to eliminate colonies around electrical and plumbing casings and housings. Injectable aerosol products containing pyrethrins, or similar products, give rapid control. Hydramethylnon, abamectin or spinosad baits applied to individual fire ant mounds will control colonies in about 1 week, even if a colony is located within the structure. Do not use liquid drenches, sprays, or products that may damage insulation around electrical fixtures. Treating a larger area around the electrical structure is optional. Mound and area treatments are described in the section on Home Lawns and Other Ornamental Turf Areas. Be extremely careful when applying pesticide around water systems and well heads to prevent contamination of wells and ground water. Once ants are eliminated, remove debris and soil from the equipment housings to reduce the possibility of short circuits.

2

Step 2. Treat the inside of equipment housings with products labeled for this use, such as State Fire Ant Killer® (containing resmethrin), Rainbow Insect Control® (chlorpyrifos), Stutton® JS 685 Powder (synergized pyrethrins and silica gel), Ascend® (abamectin), or Elastrel® or Hot Shot® No-Pest Strip insecticide (dichlorvos).

Maintenance

After ants are removed from the electrical equipment, prevent reinfestation and damage. Where possible, seal all sensitive electrical components, particularly those that are not insulated. Examples are plastic housings containing contact points of switches, relays and circuit breakers.

Spray long-residual contact insecticides around housings, making sure to avoid the electrical circuitry or components. Apply specifically labeled products to the housing itself or to the mounting pad (see Step 2 in the treatment program above).

Home gardens


Okra

Ants occasionally feed on vegetable plants in home gardens. They tunnel into potatoes underground and feed on okra buds and developing pods. The worst damage usually occurs during hot, dry weather. Ants may be a nuisance to gardeners during weeding and harvesting. Ants prey on some garden pests such as caterpillars, but protect or “tend” others, such as aphids, by keeping natural enemies away.


Treatment options

1

Ant mounds can be shoveled out of the garden or treated with very hot water, taking care not to disturb plants or allow hot water to contact them.

2

Only a few products (those containing carbaryl, pyrethrins, pyrethrins plus diatomaceous earth or rotenone) have been registered for treating ants in vegetable gardens.

3

Granular products containing carbaryl (Sevin®) or carbaryl plus metaldehyde have been registered for “ants” foraging in the garden. Products containing diazinon or chlorpyrifos are registered for “soil insects” in home gardens; they can be applied before planting and may provide some temporary control of foraging fire ants. Follow all preharvest intervals indicated on the label when using a pesticide on and around food plants.

4 The bait product Extinguish®, which contains methoprene, is now registered for use in “cropland.” Bait products, however, are not specifically registered for use inside home vegetable gardens, though they can be applied outside the garden’s perimeter. Foraging ants from colonies both inside and outside the garden will collect the bait and take it to their colonies.
5

To keep ants from entering a garden, manage them properly in the surrounding landscape. Products registered for controlling ants in turf grass can be applied outside the perimeter of the garden as a barrier, or used to treat individual mounds near the garden.

Compost piles, mulched flower beds, pavement cracks, etc.

Fire ants invade compost piles and mulched flower beds seeking warmth and moisture. They also nest under cracked pavement, removing dirt from underneath sidewalks and roadways and aggravating structural problems. Colonies in these sites may be difficult to locate precisely. When the exact location of a fire ant colony is unknown, treat the area of greatest ant activity with a fast-acting bait product containing hydramethylnon, abamectin or spinosad.

Around bodies of water

Near water

Fire ants require water to survive and are often found near creeks, run-off ditches, streams, rivers, ponds, lakes and other bodies of water. If surface water is unavailable, they tunnel down to the water table many feet below the ground. Every effort must be made to avoid contaminating water with pesticides. Fire ant bait products contain very small amounts of active ingredients and can be applied close to shorelines, but not directly to the water. To decrease the risk of runoff into waterways, apply baits when ants are actively foraging. Near water or in drainage or flood-prone areas, individual mound treatments should be made with care, using products such as acephate (Orthene®) that have low toxicity to fish. Pyrethrins and rotenone products should not be used because they are highly toxic to fish. Do not apply surface, bait or individual mound treatments if rain is likely to occur soon after treatment.

Organizing a Community-Wide Fire Ant Suppression Program

Fire ant management programs can be successful, but because they are usually implemented by individual landowners and managers, reinfestation from nearby untreated areas generally occurs. Many of the baits on the market today came from efforts to develop products suitable for area-wide treatment programs, and are best suited for large-scale use.

Despite great public concern, neither the state nor federal government is currently planning or funding any large-scale fire ant treatment programs. It is up to local organizations to decide on the best IPM strategy for a particular situation. With the help of experts in the field, any group can organize an effective fire ant suppression program.

The Two-Step Method (Program 1) for Home Lawns and Other Ornamental Turf Areas is often the method best suited for community-wide treatment. Homeowners and land managers may still need to treat a few mounds (step 2) between large-scale bait treatments, but they will need to treat far fewer than if no bait had been applied. In other areas, where ant surveys have documented that there are few imported fire ants and many competitor ant species, Program 2, or program combinations, may be more suitable.

Matching the program to your resources and needs

Basic education is critical. If you treat and your neighbor does not, you will find your yard is quickly re-infested. If you educate your neighbors, you can coordinate your battle against the imported fire ant more effectively and efficiently. Developing leadership in some neighborhoods may be difficult, but not an insurmountable problem. Many states have agencies that can help in organizing communities, be it a neighborhood watch program or a fire ant management program. There are many ways people can work together to conduct community-wide fire ant suppression programs.

Coordinating neighborhood treatment

Homeowners can coordinate treatment of their entire neighborhood each year, usually once in the fall and once in the spring. Each homeowner should receive instructions on:

1) appropriate fire ant bait products to purchase; 2) how to properly broadcast a bait; and 3) treatment date(s). Each homeowner is expected to make his own applications or arrange for treatment on the designated treatment date(s). Contingency dates should be scheduled in case rain is forecast or the temperature is less than 65 or greater than 90 degrees F on the primary treatment date. Volunteers can be enlisted to treat common areas, vacant lots and yards of homeowners who are unable to make applications themselves.

Working through homeowner associations

Homeowner associations might contract with a local commercial applicator to broadcast fire ant bait over the entire subdivision periodically, including common areas and medians. The contractor should be asked to evaluate the area and re-treat areas as needed.

Working through city and county government

aerial view

Some states have legislation or other laws in place that could aid your community in organizing treatment programs, (e.g., fire ant abatement legislation in Arkansas, or public health laws in many states). With enough citizen support, local governments can establish fire ant control programs that treat public areas and perhaps allow homeowners to have their properties treated for a fee. The municipal or county government could contract with a commercial pest control applicator. Advertising should encourage entire blocks or neighborhoods to sign up, because the larger the area treated, the longer lasting the control. Treatments would include annual broadcast applications of a fire ant bait, follow-up checks, and possibly individual mound treatments as needed. The fee paid by individual landowners could pay for the program.

A city government might help coordinate the aerial application of a fire ant bait to an entire town. Areas where baits must not be applied, such as swimming pools and vegetable gardens, would have to be covered during application. Widespread citizen support would be essential. The aerial applicators contracted by the city would have to agree to modify equipment to apply the recommended amount of bait per acre, heed the FAA flying height over populated areas, and avoid bodies of water and agricultural areas where food is produced. Make sure the product(s) used is registered for application to the sites treated. Many volunteers would be needed to successfully coordinate and implement this program.

Planning to ensure success

Determine treatment areas.

Some localized areas, even within heavily infested regions, have little or no imported fire ant infestation. Surveys should be conducted to determine if the number of imported fire ant mounds is high enough to justify treatment, or what type of treatment is necessary.

Respect individual differences.

Sensitivity to fire ants and to the use of insecticides varies dramatically from person to person. Some individuals might not want to participate in a control program because they believe fire ants are not a problem and serve useful purposes, or because they are opposed to using insecticides, natural or otherwise, on their property. At the other extreme are people who want no fire ants on their property and don’t care about the methods used to achieve that goal. Participation in an area-wide program should be voluntary or decided upon through a democratic process.

Promote education and recognize limitations.

The strengths and limitations of the program should be acknowledged. For instance, a broadcast bait will eliminate most (usually 90 to 95 percent) of the fire ant mounds in an area temporarily (6 to 18 months). It will not eradicate them permanently. The speed at which suppression will occur is rather slow. Periodic, coordinated re-application will be necessary to maintain control. Between broadcast treatments, some individual colonies may require individual mound treatment. Properties that border untreated areas such as agricultural lands, water edges, flood plains and wilderness will likely be reinfested unless the borders of these areas are treated to form a barrier or buffer zone.

Follow pesticide laws and regulations.

In each state there is an agency that regulates the commercial application of pesticides (e.g., Structural Pest Control Board in Texas, Louisiana Dept. of Agriculture and Forestry). Although you can apply insecticides on your own property, you can not treat other yards in the neighborhood for a fee without a license. State laws mandate that anyone applying insecticides for a fee be licensed and insured. Anyone using “restricted use” insecticides must have a valid commercial or non-commercial pesticide applicator’s license. In some states, there are special regulations governing the use of pesticides to treat public school grounds.

Read and retain the insecticide product label.

Those who use insecticides must keep the label with the product. Never purchase a large quantity of insecticide and repackage, divide, or store it in a container without the label. Always follow the directions on the product label.

Take bids and review credentials.

Before contracting with a commercial applicator company or private pest control operator, get several bids based on the specific services you require. These firms must be licensed by the appropriate state agency.

Fire Ant Treatment Methods

Treatment methods and products vary greatly in effectiveness, speed of activity, practicality (labor requirements), toxicity to the user and the environment, compatibility with other options, and cost. Carefully study available treatment methods and their proper use in order to choose the best one for a particular situation. Many methods and products have been evaluated. Information is available from county Extension agents and Extension entomologists. Individual mound treatment cost ranges from about $0.15 to more than $1.00 per mound, and bait treatments can cost $8.00 per acre or more.

Natural and

Status and Revision History
Published on Sep 1, 2000
Re-published on Mar 13, 2009
Reviewed on Mar 30, 2012
Reviewed on Dec 20, 2016