Fire Ant Suppression and Eradication
The red imported fire ant Solenopsis invicta has plagued U.S. farmers, homeowners, livestock, pets, and wildlife ever since its accidental introduction at Mobile, Alabama, in the 1930s. The red imported fire ant has continued to spread and currently infests Alabama, Arkansas, California, Florida, Georgia, Louisiana, Mississippi, New Mexico, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, Virginia and Puerto Rico. This stinging native of South America is also a concern for nursery shippers in infested states. When nurseries ship from infested areas to uninfested areas of the country, they are required by law to take special precautions to prevent the fire ants from moving with plants or soil. Precautions are mandated by the Federal Imported Fire Ant Quarantine regulating such nursery stock shipments.
In 1989, the first fire ant infestation was detected in the Commonwealth of Virginia. Since that time, fire ant infestations have been confirmed in eight counties and ten independent cities. To date, all fire ant infestations appear to have been introduced into Virginia on nursery stock or other plant products from infested areas. With assistance from USDA, the Office of Plant Industry Services previously attempted to eradicate each fire ant occurrence, but now that the pest is thoroughly established in the Tidewater area, VDACS will no longer treat infestations within the quarantine area. We will concentrate on new infestations that may appear outside the quarantine area. Our inspectors use appropriate treatment methods recommended and outlined by the USDA.
Fire ant mounds are found in warm, sunny locations such as landscape beds, lawns, around trees and shrubs, along sidewalk cracks and against buildings. If disturbed, theses ants are generally aggressive and can inflict painful stings. Fire ants are invasive pests of growing concern in our state. If you suspect that you have discovered a red imported fire ant infestation, please use caution and contact your local extension office or the Virginia Department of Agriculture and Consumer Services at 804.786.3515.
- What are Fire Ants?
- What damage do Fire Ants cause?
- How can you identify Fire Ants?
- How can I avoid being stung by Fire Ants?
- How does a colony begin?
- How do Fire Ants spread?
- How large is a colony?
- When the ground is dry, Fire Ant mounds disappear.
Are the mounds dead?
- How can landowners control Fire Ants on their property?
- Where are Fire Ants in the United States?
- Where can I find more information on Fire Ants?
Information regarding the movement of regulated articles
- What are regulated articles?
- Can regulated articles be moved freely within the quarantine area?
- Can regulated articles be transported out of the quarantine area?
- What are the advantages of a compliance agreement and whom do I contact to obtain one?
Virginia’s Fire Ant Quarantine
- Why is Virginia implementing the Fire Ant quarantine?
- What areas of Virginia are included in the temporary Fire Ant quarantine?
- Does North Carolina have a Fire Ant quarantine?
What are Fire Ants?
The Imported Fire Ant, or simply the Fire Ant, is an introduced species that is notorious for its aggressive behavior. Fire Ants can cause serious health problems for humans due to their aggressive nature and sting. Fire Ants clamp onto their targets with powerful jaws and sting their victims repeatedly. Each sting injects a dose of venom that causes a burning sensation. The stings raise itching blisters that can become infected. In sensitive victims, the stings can cause anaphylactic shock (symptoms include trouble breathing and fainting) or even death.
What damage do Fire Ants cause?
In addition to stings on humans, Fire Ants can cause damage to several agricultural commodities, livestock, companion animals and wildlife. They can attack and sometimes kill newborn domestic animals. Fire Ants can also destroy seedling corn, soybeans, and other crops. These insects feed on buds or fruits of many plants and may remove bands of bark from young trees, often killing them. Additionally, the hard, cone-shaped nests of Fire Ants can result in mounds as high as two feet, making it difficult to cultivate and harvest crops from infested fields. Fire Ant mounds are unsightly hazards in yards, parks and other recreational areas where they are especially dangerous to children and pets.
How can you identify Fire Ants?
Identifying Fire Ants is difficult because they look much like ordinary ants. They are 1/8 to 1/4 inch long and reddish brown to black in color. Fire Ants are probably best distinguished by their aggressive behavior and characteristic mound-shaped nests; when their mound is disturbed, thousands of ants will crawl out.
How can I avoid being stung by Fire Ants?
Being aware of your surroundings at all times will enable you to avoid Fire Ant mounds. Some Fire Ant mounds are very small and difficult to detect, therefore taking the time to survey an area is important. If Fire Ants do crawl onto your skin, they first bite with their mandibles in order to anchor for the thrust of the sting. As soon as you feel this pinching sensation, quickly sweep the ants off before they actually sting, thus reducing the likelihood of additional injury.
How does a colony begin?
A new colony begins with a “nuptial flight” of winged males and winged females, usually on a warm, spring day. After mating occurs, males drop to the ground and die. Females seek out nesting sites and burrow underground. A new queen sheds her wings and lays 12 to 24 worker eggs, which she tends constantly. Upon hatching, the workers, all of which are sterile females, take over all colony functions except reproduction, while the queen only mates and lays eggs. She can produce more than 200 eggs per day.
How do Fire Ants spread?
Natural dispersal occurs during the mating process when a queen starts a new colony. Fire Ants spread slowly through natural dispersal, but they can travel longer distances when colonies are moved in soil, plants with roots and soil attached, nursery stock, grass, sod, hay, logs, beehives and any equipment that contains soil.
How large is a colony?
Fire Ant colonies vary in size, but a mature, three-year-old colony typically contains 250,000 workers, which are sterile females, and hundreds of reproductive males and potentially reproductive females. A colony population can grow to 300,000 ants. In addition to single-queen colonies, many Fire Ant colonies have multiple queens, increasing manyfold the number of mounds in an infested area.
When the ground is dry, Fire Ant mounds disappear. Are the mounds dead?
Fire Ant brood (larva) is sensitive to temperature and humidity. Worker ants move the brood up high when it is wet. That's why you see tall mounds after rains. When conditions are dry, the workers move the brood deeper to more humid chambers and you may see no mounds at all. Mounds can extend as much as four feet below the surface.
How can landowners control Fire Ants on their property?
Control of Fire Ants is made difficult by the protective behavior of the workers that guard the queen. If the colony is disturbed, workers will hurriedly carry the queen to a safe location where the queen will begin a new colony. Therefore, the best control is not a method that will merely kill workers, but one in which a bait is applied that will be taken back to the nest by foraging ants where it will either kill the queen or render her sterile. Baits combine a food to attract the ants with an insecticide or insect growth regulator (a pesticide that works by disrupting the ants’ reproductive system). Although baits are slow-acting, they are often the best way to reach the queen and eliminate the colony. Many times, using insecticides that kill on contact will simply force the colony to move to a new location. Since the worker Fire Ants move the queen in order to protect her, these types of treatments are usually ineffective in killing the colony. Individuals applying any treatment should read the insecticide labels closely and follow all directions. You may wish to consider discussing your Fire Ant treatment needs with a pest control professional.
Where are Fire Ants in the United States?
Fire Ants were accidentally brought to the United States from South America. Since arriving in Mobile, AL, they have spread to all or parts of Alabama, Arkansas, California, Florida, Georgia, Louisiana, Mississippi, New Mexico, North Carolina, Oklahoma, Puerto Rico, South Carolina, Tennessee, Texas, and Virginia.
Why is Virginia implementing the Fire Ant quarantine?
The Office of Plant Industry Services (OPIS) in the Virginia Department of Agriculture and Consumer Services (VDACS) has attempted to eradicate Fire Ant colonies since 1989. However, recent data confirm that Fire Ants have now become established and they are spreading naturally in the Tidewater area, making outright eradication no longer achievable. From 1989 to 2007, OPIS treated an average of 33 Fire Ant sites per year. In the last six months of 2008, OPIS treated 642 sites in the Tidewater area. This dramatic increase indicates the Fire Ant has become established in the Tidewater area and cannot be eradicated. The quarantine is necessary to reduce the rate of spread of Fire Ants to the areas of Virginia that are currently not infested
What areas of Virginia are included in the Fire Ant quarantine?
The counties of James City and York, and the cities of Chesapeake, Hampton, Newport News, Norfolk, Poquoson, Portsmouth, Suffolk, Virginia Beach and Williamsburg.
Does North Carolina have a Fire Ant quarantine?
Yes, in North Carolina, portions or entire areas in more than 70 of that state's 100 counties are considered infested with Fire Ants, including the counties of Camden, Currituck, Gates, Hertford and Northampton, which border the Tidewater area. Quarantines have also been in place for several years in other Southern and Gulf Coast states, where problems with Fire Ants have been particularly serious.
- Your city/county agricultural extension agent, listed in the local government section of your telephone directory under Virginia Cooperative Extension Service
- VDACS’ Office of Plant Industry Services at 804.786.3515 in Richmond or 757.562.6637 in Franklin
- USDA-APHIS Fire Ant Web site
INFORMATION REGARDING THE MOVEMENT OF REGULATED ARTICLES
What are regulated articles?
The Fire Ant and any article that is capable of transporting Fire Ants are considered to be regulated articles. The Fire Ant quarantine lists the following as regulated articles: (1) any life stage of Imported Fire Ant; (2) soil; (3) plants with roots with soil attached, or roots and rhizomes of plants with soil attached; (4) grass sod; (5) used soil-moving equipment, unless free of all non-compacted soil; (6) used farm equipment, unless free of all non-compacted soil; (7) hay and straw, including pine straw, that has been stored in direct contact with the ground; (8) honey bee hives that have been in direct contact with the ground, including hive stands containing soil; (9) logs, pulpwood and stump wood with soil attached. In addition, any other article or means of conveyance is considered a regulated article, when such article is determined by a VDACS inspector to present a risk of spread of the Imported Fire Ant. Note: Plants maintained indoors in a home or office environment and not for sale are not considered to be a regulated article.
Can regulated articles be moved freely within the quarantine area?
Yes, regulated articles can be moved freely within the quarantine area, thus avoiding any compliance burden on businesses and residents.
Can regulated articles be transported out of the quarantine area?
Yes, regulated articles that are certified free of Imported Fire Ants can be transported out of the quarantine area. VDACS’ Office of Plant Industry Services inspectors can conduct an inspection to determine if regulated articles meet the conditions required to be certified Fire Ant free. Contact VDACS’ OPIS at 804.786.3515 in Richmond or 757.562.6637 in Franklin to arrange an inspection.
Businesses and individuals that ship regulated articles out of the quarantine area on a regular basis are urged to consider entering into a compliance agreement with VDACS and USDA’s Animal and Plant Health Inspection Service (APHIS) to allow for self-certification of regulated articles. Regulated articles shipped under a compliance agreement do not require inspection by VDACS.
What are the advantages of a compliance agreement and whom do I contact to obtain one?
Businesses and individuals that ship regulated articles out of the quarantine area on a regular basis can enter into a compliance agreement with VDACS and USDA-APHIS that allows for self-certification of regulated articles. This self-certification eliminates the need to contact VDACS since regulated articles shipped under a compliance agreement do not require inspection by VDACS. Contact OPIS at 804.786.3515 in Richmond or 757.562.6637 in Franklin.