Pest Management

COLUMBIA - Scientists are pleased with the first year of a project that puts natural biological warfare into the battle against the red imported fire ant.

Fire ant samples taken from McEntire Air National Guard Station in May indicate that a parasitic fly and a disease pathogen released last spring have survived South Carolina's winter. That's good news for Clemson University, the U.S. Department of Agriculture (USDA), the Department of Defense and the Environmental Protection Agency (EPA).

"Red imported fire ants came here from South America pathogen- and predator-free early in the last century," said David Williams, research entomologist with the USDA's Agricultural Research Service Center for Medical, Agricultural and Veterinary Entomology. With nothing to stop them, they have spread to more than 310 million acres across the South.

The ants are a $3.8 billion problem annually for the nation. In South Carolina 1.4 million households spend well over $100 million a year for insecticides, household repairs and medical and veterinary care because of the ants. At McEntire airbase, they have caused considerable damage to electrical controls for the runway sequence flashing lights.

To balance the scales, scientists went to South America looking for some of the baggage the ants left behind: pathogens and predators. A disease, carried by the protozoan Thelohania solenopsae, and a predator, the phorid fly, are two of the natural enemies they brought back to the United States.

The disease puts fire ant queens on a starvation diet so the colony slowly diminishes in size as no new eggs are laid, and the fly deposits its eggs in the ants' bodies where the egg turns into a larva that feeds on the ant's brain and eventually decapitates its victim. Both the disease and the fly only affect the red imported fire ant and have been approved by the EPA for release in this country.

Mac Horton, Clemson entomologist, said that it will take two to three years for either organism to reach a population density strong enough to begin significant expansion. "Once the phorids reach that saturation point, they have the potential to expand outward as much as 10 miles a year on average," he said. "It could be pretty exciting when we check the McEntire site next spring."

Horton said scientists believe that the two biological agents, along with other biological controls being studied, could eventually reduce overall fire ant populations by 50-60 percent through natural means. These studies are being conducted in 11 states infested with the imported fire ants.

"We think that we can get these biological agents to high enough levels to begin showing an impact within three to four years," said Williams. "The beauty of it is that they're self-sustaining, not like chemical treatments which you have to apply repeatedly."

Williams' laboratory in Gainesville, Fla., rears about 1,500 phorid flies a week, but a new agreement among the Florida Department of Agriculture, USDA Animal and Plant Health Inspection Service (APHIS) and USDA Agricultural Research Service (ARS) promises to boost that number to 10,000-15,000 flies a week by next spring. "We'll give the flies to universities around the South so they can rear them and spread them around," he said.

Williams said that seven years of tests with the biological controls indicate that the disease will not infect anything but imported fire ants. The only native ants that the phorid flies attack are native fire ants, which can be a nuisance like the red imported fire ants.

Horton said that a chemical from Aventis called fipronil, which is being tested at McEntire airbase and at nearby Ft. Jackson, shows promise for controlling red imported fire ants. Material for the test was provided and applied by Laurence Mudge, field development specialist for Aventis Environmental Science.

Fipronil has just received labeling approval from the Environmental Protection Agency, and Mudge expects product marketing to begin this fall. Plots of 1/8th acre have very low fire ant populations a year after treatment. Mounds in individual plots can be counted on one hand where fipronil has been used. By contrast, in plots where fipronil has not been used, as many as 55 mounds can be found.

Williams said that the combination of fipronil and biological controls could dramatically change the way Southerners treat for red imported fire ants. "Rather than putting out two or three chemical treatments a year, you could put out one every two or three years," he said.

Having fewer fire ants at McEntire will make Alison Hyder's job a bit easier. She is an environmental scientist with the S.C. Army National Guard in Columbia and a member of the Guard. She assisted with the initial release of the phorid flies and supervised the release site to encourage fly survival in the early weeks, with help from Sgt. Shelvin Boykin of the Guard and Clemson Extension agent Tim Davis of Richland County.

"A major impact on the fire ant population would allow me to focus on other pest management issues," she said. "Fire ants take up 90 percent of the time I spend on pest management right now."

Hyder said that red imported fire ants have not only interrupted training sessions, they have knocked out vehicles and shorted out air conditioning units costing approximately $5,000 each.

Herb Bolton of the USDA's Cooperative State Research, Education and Extension Service (CSREES) serves as national program leader for Army Environmental Programs and as part of the evaluation team. The Department of Defense is keenly interested in the tests at McEntire and Ft. Jackson.

"We have a lot of military facilities in the Southeast, and fire ants affect a lot of groups training on the ranges. They also affect electrical boxes, people on the bases, children at child care centers, recreation areas and wildlife," he said. "This should tell us if there is a way to reduce fire ants by integrating chemicals with biological controls."

Funding from the EPA's Pesticide Environmental Stewardship Program, along with support from the Army Environmental Center and the Armed Forces Pest Management Board, was essential in making the multi-agency effort possible.

"Glenn Williams of EPA's Pesticide Environmental Stewardship Program provided critical support for this project," said Horton. "EPA saw it as a way to manage an important pest while minimizing negative effects on the environment."

END

DATE: 12-14-98

CONTACT: Mac Horton, (864) 656-3113 mhorton@clemson.edu

Clyde Gorsuch, (864) 656-5043 cgrsch@clemson.edu

WRITER: Debbie Dalhouse, (864) 656-0937 ddalhou@clemson.edu

CLEMSON FIRE ANT RESEARCH USES BIOLOGICAL APPROACH

CLEMSON - In the ongoing war to control fire ants, a new, biological approach is being tested at Clemson University. Entomologists here have introduced a naturally occurring disease into fire ant colonies as a means to reduce their population growth.

The disease keeps fire ant populations under control in their native South America, but was only recently found in this country. Without any natural predators, imported fire ants have run rampant across the southern states and are now spreading to colder climates.

"Using natural means to control fire ant populations restores balance to the environment," said Mac Horton, a Clemson entomologist and one of the project leaders for fire ant research, along with entomologist Clyde Gorsuch. "Fire ants are having as harsh an impact on the environment as anything man could do. They dominate many native plants and animals and cause the natural plant and animal systems to break down."

The ants also have a major economic impact. Throughout the southern states, damage estimates are in the billions as the aggressive ants invade electrical equipment, agricultural fields, homes and gardens. Their painful sting sends thousands of people to the doctor each year, and can be deadly for about five out of every 1,000 people.

Clemson scientists are working with the Agricultural Research Service of the U.S. Department of Agriculture (USDA) to test this and another biological control method in a multi-state project.

The disease that has been introduced is carried by a micro-organism, called Theolohania, that reduces the ability of the queen to lay eggs so the colony slowly dies over a period of six to eight months. Although it does not affect any other insects, the disease still required regulatory approval to be used in the tests.

The scientists introduced infected fire ant larvae into a number of test mounds that are being monitored over a two-year period to track fire ant population activity, using satellite technology. Researchers are overlaying the ant population data with other activity, such as human traffic and plant species, to track impact. Findings will be shared with other states to generate data across a wide range of climates and conditions, accelerating the pace of research nationwide.

In another study, Clemson and USDA scientists released "decapitating flies" from Brazil at the Myrtle Beach National Golf Course near Conway. The flies, Pseudacteon tricuspis, help keep fire ant populations in check in their native South America. The fly deposits an egg into the ant's body. The egg turns into a larva that eventually moves into the ant's head. Feeding on the ant's brain, the larva grows to fill the ant's entire head.

Near hatching time, the larva dissolves the tendons that hold the head onto the body, actually cutting off the ant's head. Then the larva finishes growing, emerges and the cycle begins again.

The flies, like the microorganism, were tested extensively before they were allowed into the United States. They are environmentally friendly. Only the red imported fire ant attracts them - people, food, waste and other insects do not interest them.

In addition to the releases near Myrtle Beach, the flies have also been released near the Clemson campus to test their adaptability to the colder climate of the Upstate.

"The biological control agents are one of several strategies that we are testing to control the pests," said James R. Fischer, director of South Carolina Agriculture and Forestry Research at Clemson. "Our scientists are also searching for other environmentally sensitive management strategies, such as competition and predation by native ants, other potential parasites and predators, and tests to determine the ecological peculiarities of the ants in North America."

This work is funded by the state General Assembly and the USDA through the Clemson research system.

The most common method of controlling fire ants is the use of bait that the ants discover while foraging and then take back to the colony. The bait technology has been tested by Clemson scientists since the 1960s and refined in partnership with the USDA and various commercial manufacturers.

"It took 30 years to understand the biological complexity of fire ants," said Horton. "The adults use juveniles to convert solid food to liquid food that passes through several adults before it's given to the queen. They do this to protect the queen, so we had to develop a very slow-acting bait."

When the fire ants detect some pesticides, they often build a new nest before the treated colony completely dies out. As a result, Clemson entomologists recommend broadcasting the bait rather than simply treating the visible mound.

Clemson Extension agents work closely with Clemson Regulatory and Public Service specialists to educate homeowners, agricultural producers and others on the various methods and regulatory requirements for controlling fire ants.

END

DATE: 3-12-99

CONTACT: Craig Allen, (864) 656-4461 allencr@clemson.edu

WRITER: Debbie Dalhouse, (864) 656-0937 ddalhou@clemson.edu

CLEMSON RESEARCHERS TRACKING FIRE ANT IMPACT ON WILDLIFE

CLEMSON - The imported fire ant is a major nuisance to people, but may also be causing problems for bobwhite quail and other wildlife. Quail populations have been declining for several years, even on plantations primarily managed for quail, and scientists suspect that fire ants may be a contributing factor.

"Quail are potentially vulnerable to both direct and indirect fire ant impacts," said Mac Horton, a Clemson University entomologist and one of the project leaders for fire ant research.

Graduate student Evan Myers is conducting the quail research. Fire ants are suspected of attacking quail chicks, reducing weight gain and survival rates, and of competing with quail for insect food resources. To document the impact of fire ants on quail, the Clemson researchers are conducting a large-scale experiment in coastal South Carolina.

Researchers will treat five sites, each between 300-500 acres, to reduce fire ant populations, then monitor the sites over a period of several years to track quail populations and the effect fire ants have on important insect food resources. Results from the test sites will be compared with five control sites of similar size.

"The fire ant represents a major threat to the wildlife diversity of South Carolina and the nation," said Craig Allen, project leader for the wildlife research at Clemson. "Data from this study may also shed light on how fire ants impact other ground-nesting animals."

In another project, Clemson researchers are tracking the fire ants' impact on endangered wildlife across the state. Graduate student Leslie Parris is using regional sampling, satellite imagery and computer mapping to predict the presence of fire ants in wildlife habitats. This information, overlaid with maps of endangered species and information on the life cycles of the animals, will enable scientists to predict risk levels for various endangered species and geographical areas.

"This research will investigate the effects of the fire ant on endangered wildlife statewide rather than studying each species individually," said Allen.

Fire ants have also been implicated in numerous fish kills throughout the Southeast. Heavy thunderstorms can wash the ants into waterways where they may be consumed by fish. Clemson researchers are studying the impact of ingesting fire ants in several species of fish, including minnows and game fish. Graduate student Quenton Fontenot is determining if ingesting the ants is toxic to fish or reduces their growth.

For these projects, Clemson is working in cooperation with several partners, including the South Carolina Department of Natural Resources, S.C. Cooperative Fish and Wildlife Research Unit and the USDA Agricultural Research Service.

The wildlife research is part of a wide range of investigations Clemson is conducting on managing fire ants. This research is funded by the South Carolina Agriculture and Forestry Research System and the South Carolina General Assembly.

END

DATE: 6-28-99

CONTACT: Clyde Gorsuch, (864) 656-5043 cgrsch@clemson.edu

Mac Horton, (864) 656-3113 mhorton@clemson.edu

Sanford Porter, USDA-ARS (352) 374-5914

WRITER:Giles Singleton, (864) 656-3876 gsngltn@clemson.edu

FIRE ANTS FLEE FROM NATURAL ENEMY

MYRTLE BEACH - Clemson University is conducting cutting-edge research to find a natural enemy of red imported fire ants. These natural enemies are called "decapitating flies" or Pseudacteon tricuspis. Originally from Brazil, they are smaller than the head of a pin.

When a fire ant mound is disturbed, the flies swarm and attack the ants, which run for cover. The flies deposit eggs into the ants' bodies, beginning a deadly process that takes an average of five to 12 weeks to play itself out.

On June 23, Clemson University and S.C. Rep. W.D. "Billy" Witherspoon hosted the first public release of biological fire ant parasites in South Carolina at Myrtle Beach National Golf Course near Conway. Witherspoon sponsored legislation resulting in a $200,000 grant from the state legislature for 1998-'99 fire

ant control research. The demonstration release was a joint venture of Clemson University and the United States Department of Agriculture (USDA).

The USDA's ongoing Fire Ant Initiative with the Southern Legislative Conference funded the release in Conway as part of an ongoing multi-state study. These flies have currently been released in six states: South Carolina, Alabama, Florida, Oklahoma, Arkansas and Texas.

"In South America, when the decapitating flies swarm, the ants cower, or try to get back into their mound," said USDA entomologist Sanford Porter, who has studied the flies for the past five years. "It's like a helicopter attack in miniature. As

the plague of flies descends, ant after ant freezes in place."

Porter raises the flies in large numbers in a laboratory. He works with the USDA's Agricultural Research Service in Gainesville, Fla.

"The ant stiffens as the fly deposits its egg into the ant's body," said Clyde Gorsuch, the Clemson University entomologist who directs Clemson's participation in this study. "The ant's legs spread out, its back curls up. Other ants run up to it and touch it, as if they know the ant is going to die."

The egg turns into a larva, or worm, that eventually moves into the ant's head. Feeding on the ant's brain, the larva grows to fill the ant's entire head.

Near hatching time, the larva dissolves the tendons that hold the head onto the body, actually cutting off the ant's head. Then the larva finishes growing, emerges, and the cycle begins again.

"Rearing these flies is too expensive for the homeowner," Porter said, "but we hope releases of decapitating flies and other natural enemies will give permanent, wide-area suppression of the fire ant population. South Carolina, the other states and the USDA are doing this for the public's welfare."

The flies were tested extensively before they were allowed into the United States. They are environmentally friendly. Only the red imported fire ant attracts them - people, food, waste and other insects do not interest them.

In addition to the releases near Myrtle Beach, companion releases near the Clemson campus will test the adaptability of the fly to the colder climate of the Upstate.

"In Florida and Texas, they are recovering descendants of the first year's flies," Gorsuch said. "So this method of suppressing fire ants looks very promising for the whole Southeastern environment."

END

DATE: 12-13-99

CONTACT: Mac Horton, (864) 656-3113 mhorton@clemson.edu

David Oi, USDA-ARS (352) 374-5987 doi@gainesville.usda.ufl.edu

Sanford Porter, USDA-ARS (352) 374-5914 sporter@gainesville.usda.ufl.edu

Stanley Schuman, M.D., (843) 792-2281 schumash@musc.edu

WRITER: Debbie Dalhouse, (864) 656-0937 ddalhou@clemson.edu

CLEMSON FIRE ANT RESEARCH USES BIOLOGICAL AND CHEMICAL WEAPONS

CLEMSON - Since the red imported fire ant has no natural enemies in the United States, Clemson University researchers are using biological weapons imported from South America to help control the pests. In cooperation with the USDA's Agricultural Research Service, Clemson scientists have released "decapitating flies" that cause the ant's head to fall off as fly larvae develop inside the ant's body.

These natural enemies,Pseudacteon tricuspis, are originally from Brazil and are smaller than the head of a pin. Clemson scientists released the decapitating flies in the summer of 1999 at Myrtle Beach National Golf Club and near the Starkey Center on the University campus.

When a fire ant mound is disturbed, the flies swarm and attack the ants, causing the ants to run for cover. The flies deposit eggs into the ants' bodies, beginning a deadly process that spans five to 12 weeks.

"The ant stiffens as the fly deposits its egg into the ant's body," said Clyde Gorsuch, a Clemson entomologist and one of the project leaders for fire ant research, along with entomologist Mac Horton. "The ant's legs spread out, its back curls up. Other ants run up to it and touch it, as if they know the ant is going to die."

The egg turns into a larva that eventually moves into the ant's head. Feeding on the ant's brain, the larva grows to fill the ant's entire head. Near hatching time, the larva dissolves the tendons that hold the head onto the body, cutting off the ant's head. Then the larva finishes growing, emerges, and the cycle begins again.

"In South America, when the decapitating flies swarm, the ants cower or try to get back into their mound," said USDA entomologist Sanford Porter, who raises the flies in his Gainesville, Fla., laboratory. "It's like a helicopter attack in miniature. As the plague of flies descends, ant after ant freezes in place."

The flies were tested extensively for possible environmental impact before they were allowed into the United States. Only the red imported fire ant attracts them - people, food, waste and other insects do not interest them. The release of decapitating flies is part of the USDA's ongoing Fire Ant Initiative with the Southern Legislative Conference that includes Alabama, Arkansas, Florida, Georgia, Louisiana, Mississippi, North Carolina, Oklahoma, Tennessee, Texas and Virginia.

Another biological weapon being used in Clemson research is a disease carried by a protozoan, called Theolohania. The disease reduces the ability of the queen to lay eggs so the colony slowly dies over a period of six to eight months. The disease keeps fire ant populations under control in their native South America, but was only recently found in this country. Although it does not affect any other insects, the disease still required approval by the federal Environmental Protection Agency to be used in the tests.

Clemson scientists, working with USDA entomologist David Oi, introduced infected fire ant larvae into test mounds on the University campus in the summer of 1998. The mounds are being monitored every two months over a two-year period to track fire ant population activity, using satellite technology. Researchers are overlaying the ant population data with other activity, such as human traffic and plant species, to track impact.

"Fire ants are having as harsh an impact on the environment as anything man could do." said Clemson entomologist Mac Horton. "They dominate many native plants and animals and cause the natural plant and animal systems to break down."

Without any natural predators, imported fire ants have run rampant across the southern states and are now spreading to colder climates. Fire ants cost South Carolina's 1.4 million households an estimated $112 million each year in insecticides, household repairs and medical and veterinary care.

"That's not counting what they cost business, industry, tourism and agriculture," Horton said. A team of Clemson agricultural economists and entomologists is planning surveys to determine just what those costs are. One University of Arkansas economist has estimated that the fire ant is a $3.8 billion problem across the South. Fire ants are more than an economic problem, however.

Clemson researchers are collaborating with family medicine physician Stanley Schuman at the Medical University of South Carolina to determine the health impact of fire ants. They report that 33,000 people in the state required medical treatment in 1998 because of fire ant stings, with more than half of them being children. There were also two deaths in South Carolina due to allergic reactions to fire ant stings.

In response to the fire ant invasion, the South Carolina General Assembly has funded Clemson's public service research and technology transfer efforts with a special appropriation of $200,000 per year. Research projects are funded through Agriculture and Forestry Research at Clemson; while technology transfer is funded through the Clemson Cooperative Extension Service.

Other research efforts include testing a new pesticide at Clemson's Sandhill Research and Education Center in Columbia and at McEntire Air National Guard Base in Charleston, where fire ants are knocking out the circuit boards in runway lights. The new chemical may be available to consumers within the next two years, pending approval by the federal Environmental Protection Agency.

"Clemson scientists are testing a variety of strategies to control fire ants," said Jim Fischer, director of Agriculture and Forestry Research at Clemson.

Research efforts include studies to map fire ant locations around the state and to find out why the ants colonize some areas and not others; to learn more about their impact on northern bobwhite, endangered species and some fish populations; how effective baits are in no-till pasture seeding operations; how nitrogen fertilizers affect fire ants; and how different cropping practices affect fire ant populations.

Horton and Clemson entomologist Tim Davis are also testing a new fire ant pesticide at Clemson's Sandhill Research and Education Center in Columbia and at McEntire Air National Guard Base in Charleston, where the ants are knocking out the circuit boards in the lights that line the runways.

The new chemical may be available to consumers within the next two years, pending approval by the federal Environmental Protection Agency. The experimental material looks promising for long-term control of fire ants that is also environmentally sensitive. One pound of the new chemical is as effective as 1,000 pounds of Dursban.

The most common method of controlling fire ants is the use of bait, such as Amdro, that the ants discover while foraging and then take back to the colony. The bait technology has been tested by Clemson scientists since the 1960s and refined in partnership with the USDA and various commercial manufacturers.

Since the queen lays up to 1,000 eggs per day for as long as seven years, fire ant colonies in South Carolina can include more than 250,000 ants, compared to fewer than 1,000 for the native ants. This is one reason why some treatments require several weeks to show results. When the fire ants detect some pesticides, they often build a new nest before the treated colony completely dies out. As a result, Clemson entomologists recommend broadcasting the bait rather than simply treating the visible mound.

Even with all these weapons in their arsenal, scientists are reluctant to predict success in the war against fire ants. "We can learn to manage them better, but we'll never eliminate them," said Clemson entomologist Clyde Gorsuch.

END

DATE: 6-16-00

CONTACT: Mac Horton, (864) 656-3382 mhorton@clemson.edu

WRITER: Debbie Dalhouse, (864) 656-0937 ddalhou@clemson.edu

PILOT PROGRAM FIGHTS FIRE ANTS ON MILITARY BASES

COLUMBIA - Fire ants are a pest to anyone enjoying the outdoors, but they can threaten national security if their mounds interfere with military preparedness activities. Mature fire ant colonies may contain more than 250,000 workers and reach infestation rates of over 600 mounds per acre. That is many times the density found in their homeland of South America because the ants have no natural enemies here.

Now, a team of military and environmental experts from across the nation is joining forces to combat fire ants on military bases, beginning with Fort Jackson, the McCready Army National Guard Training Center and the McIntire Air National Guard air base. The scientists from Clemson University, the Department of Defense, the U.S. Environmental Protection Agency and the USDA Agricultural Research Service are testing a multifaceted management approach called Integrated Pest Management (IPM) at military bases. Defense Department scientists include the U.S. Army, the S.C. Army National Guard and the S.C. Air National Guard.

"This collaboration is a first for the nation," said Mac Horton, a Clemson University entomologist helping assemble the team. "We hope our findings will lead to more effective solutions to control these invasive alien ants."

The pilot studies began June 5 - 9 on the three military sites. One site was treated with a new chemical called Fipronil, then followed by the introduction of biological control agents from the ants' native South America. A second site was treated with the chemical only, while the third plot was preserved as a control standard and received no treatment. The sites will be monitored for several months to track results of the treatments.

One of the biological control agents is a "decapitating fly," Pseudacteon tricuspis. The fly lays an egg in the ant's body. As the egg grows into a larva, it causes the ant's head to fall off. The other biological control is a disease caused by a protozoan, called Theolohania solenopsae . The disease reduces the ability of the queen to lay eggs, so the colony slowly dies over a period of six to eight months. Both biological controls affect only imported fire ants, so are approved for release in this country by the U.S. Department of Agriculture.

These control agents have been released by the USDA Agricultural Research Service on non-military test sites in several Southern states, including South Carolina. This represents the first effort at developing self-sustaining biological control agents for fire ants in this country. Biological controls offer the hope of areawide, sustained management in a way that chemicals cannot provide.

Fire ants were introduced to this country in the early quarter of this century. They have gradually spread from the port of entry at Mobile, AL, to more than 310 million acres throughout Puerto Rico and twelve Southern states from Texas to Virginia. They have also been reported in California, Arizona, New Mexico and Maryland.

Strict quarantine procedures have slowed the spread of this pest, but populations are projected to expand westward along the Pacific coast, southward into Mexico and the Caribbean, and northward along a front from Oklahoma to Virginia.

END

DATE: 10-27-00

CONTACT: Mac Horton, (864) 656-3382 mhorton@clemson.edu

WRITER: Debbie Dalhouse, (864) 656-0937 ddalhou@clemson.edu

NATURAL ENEMIES IMPROVE FIRE ANT CONTROL

CLEMSON - Early results are promising from a multi-pronged attack on fire ants at Fort Jackson by a team of scientists from Clemson University and various government agencies. The effort is the first of its kind to use an Integrated Pest Management (IPM) approach to control fire ants on a military base and may serve as a model for other sites across the country.

The three-year study began in June, using various combinations of a new chemical treatment, fipronil, and two biological controls that keep the fire ant population in check in its native habitat.

"The first evaluation, conducted in October, showed that the chemical treatment reduced fire ant populations by more than 96 percent when used in combination with the biological controls," said Mac Horton, a Clemson University entomologist who helped assemble the team of scientists. "That compares to an 87 percent reduction when fipronil was used alone."

The biological controls being used are phorid flies, a natural predator that lays its eggs inside the ants' bodies, and Thelohania solenopsae, a disease-carrying microorganism that reduces the ability of the queen to lay eggs.

Four months after their introduction at the test sites, phorid flies were found attacking fire ant workers in three different colonies. This indicates that the flies have become established at the sites. The microorganism, Thelohania solenopsae, was also found to be present in worker ants collected from colonies where it had been introduced.

Although it is too early to determine if the microorganism has spread to other colonies or to other fire ants besides the workers, the fact that it was detected in inoculated colonies is good news. To be successful, the biological controls must become self-sustaining and must prevent or delay any fire ant reinfestation into treated areas, thereby reducing the number of chemical applications needed to control the invasive ant populations.

The next evaluation of the study will occur in the spring of 2001. The team of researchers working on this project includes scientists from the USDA Agricultural Research Service in Gainesville, FL, the Environmental Protection Agency, the Department of Defense, and the South Carolina Army and Air National Guard, in addition to Clemson University. The university's participation is funded by an initiative of the South Carolina General Assembly through Agriculture and Forestry Research at Clemson.

END

DATE: 8-7-98

CONTACT: Pat Zungoli, (864) 656-3137

e-mail: pzngl@clemson.edu

Eric Benson, (864) 656-7860

e-mail: ebenson@clemson.edu

WRITER: Debbie Dalhouse, (864) 656-0937 e-mail: ddalhou@clemson.edu

CLEMSON RESEARCH FINDS NEW WAYS TO CONTROL TERMITES

CLEMSON - Termites are chewing their way through wood across the country, but research by Clemson University entomologists is finding new ways to control their damage in South Carolina and around the world.

Building codes for foamboard insulation have been modified through the efforts of Clemson entomologist Patricia Zungoli and Neil Ogg, director of statewide Regulatory and Public Service Programs based at Clemson. Termites use the foamboard insulation as a superhighway from their underground chambers to the wooden framework of homes and other buildings.

"The termites don't eat the foamboard insulation, but they do tunnel through it if the insulation extends below grade," Zungoli said. "In our research, termites were able to penetrate all the foamboard insulation products we tested to some degree. Termites were even able to get past an insecticide-treated product by tunneling behind it. For these reasons, we recommend a six-inch clearance between the insulation and ground level to deter termite activity."

As a result of their efforts, the Southern (Standard) Building Code was modified to require the six-inch clearance in regions of the United States where the probability of termite infestation is very high. It is now being considered for adoption by the International Building Code.

While the foamboard manufacturers were not pleased with the code change, they are now working with other concerned groups, including Clemson researchers, to develop ways of testing new products that stop termites. At present, some of the products are in laboratory tests, with field tests planned in the near future.

Clemson researchers have also worked with manufacturers to develop baiting systems that are being used to reduce and even eliminate termites.

"Traditional liquid treatments provide a barrier around the house, but don't necessarily affect the colony living underground," said Patricia Zungoli, a Clemson entomologist. "Now pest control operators can use a more targeted system with in-ground bait that was developed to affect the whole termite colony."

The baits, which are available through commercial pest control operators, require a professional to monitor termite activity and adjust the treatments accordingly. The monitoring stations are placed in the ground around the home or building, at first loaded with untreated wood to assess the extent of termites in the area. If activity is noted, a slow-acting insecticide in a bait material is substituted to reduce the colony. The monitor stations must be checked regularly, usually monthly, to keep the station filled with bait, as compared with the annual inspection after a traditional liquid treatment.

Clemson researchers worked with commercial manufacturers to test the in-ground bait system and are continuing to refine its applications by testing the effect of different temperatures on termite behavior and on the efficacy of the insecticide. One of the ways that they have tracked the effects of the in-ground bait is to trap termites in a wooden block on location, then bring the termites to the laboratory and feed them dye. The termites are then returned to the wooden block at the site and their movements can be tracked by periodic captures.

By weighing the amount of wood that the termites are eating, the researchers can assess the activity level of the colony; and by comparing the number of recaptured dyed termites to undyed ones, the researchers can calculate the approximate size of the colony.

The researchers are also working with manufacturers to improve the success of a new above-ground bait system that is placed inside the structure where there is a heavy termite infestation. This requires using a type of electronic stethoscope to listen to termite activity inside the walls and determine the most effective location for the bait boxes.

"The termites inside the house take the bait back to the colony that is usually located underground in the yard," said Clemson entomologist Eric Benson. "The stethoscope doubles our success rate of finding the best location to place the bait."

Researchers can be found tracking termites in nursing homes, schools and historic homes in Charleston, resort homes in Hilton Head, the Sumter National Forest in the Upstate and the laboratories at Clemson University. They have found that the state's different climates and environments all contribute to differences in termite behavior.

In addition to the native subterranean termite, they have also worked with Formosan subterranean termites in the state. While the Formosan termites have received a great deal of attention because of the level of destruction, the researchers found that the species does not eat any more than other species as individuals. The difference is that the Formosan subterranean colonies tend to be up to six times larger than native colonies. In spite of their colony size, the Formosans can be controlled using the same methods as native species.

Researchers work with the statewide Department of Pesticide Regulation, based at Clemson, Clemson Extension agents and pest control operators around the state to share these findings. Many of these information sessions are held at Clemson's Termite Training Center in Columbia that was the first of its kind and now serves as a model for similar centers that have been developed around the country. The center includes partially built house foundations where pest control operators can get a hands-on idea of proper procedures. It is used by the Department of Pesticide Regulation, Clemson Extension and private pest control companies.

Each year more than 500 pest control operators attend the Pest Control Operators' School in Columbia, one of the largest events of its kind in the

nation. The school is coordinated and sponsored by Clemson University's Department of Entomology in cooperation with the Department of Pesticide Regulation and the South Carolina Pest Control Association (SCPCA). The SCPCA is the professional association of the 660 licensed pest control businesses

in South Carolina.

"These businesses employ more than 4,000 personnel, conduct pest control for more than 25 percent of the homes, businesses and industries in the state, and annually generate gross revenues of more than $250 million," said Clemson entomologist Mac Horton.

Clemson Extension and the Department of Pesticide Regulation also hold two Master Termite Technician training sessions and two Apprentice Termite Technician training sessions each year, reaching a total of 100 professionals. Other outreach activities include the development of instructional materials on insect control for the Extension Food and Nutrition Education Program (EFNEP). The materials are used by EFNEP program assistants in their work with limited-resource

families.

Termite research is sponsored by the South Carolina Agriculture and Forestry Research System, based at Clemson.

The Department of Pesticide Regulation is the licensing agency responsible for ensuring that termite treatments meet detailed standards for the proper control of termites. Free publications on various termite treatments are available by calling (864) 646-2150.

END

DATE: 11-22-00

CONTACT: Pat Zungoli, (864) 656-3137 pzngl@clemson.edu

WRITER: Debbie Dalhouse, (864) 656-0937 ddalhou@clemson.edu

FORMOSAN TERMITES FOUND IN ROCK HILL

CLEMSON - Formosan subterranean termites have been found in a a tree that was removed by the City of Rock Hill; but Clemson University advise homeowners not to panic.

"Formosan termites are not 'super termites,'" said Pat Zungoli, a Clemson University urban entomologist. "The same treatments that are used to control native termites are also effective on Formosan termites."

This is the first time that the termites have been found this far from the coast in South Carolina, although previously they had been found even farther inland in Rutherford County, N.C.

"While this is a new county of record for the Formosan termite in South Carolina, it should not be the cause of undue concern," Zungoli said. "The Formosan termite should be treated as any other subterranean termite infestation. The only difference is that the Formosan colonies may be larger than the native termite colonies."

The colony was reported to the university by Clark Beavins, the forester for the City of Rock Hill. The Clemson team of scientists included Zungoli and Mike Weyman from the university's pesticide regulation department, as well as Eric Paysen and Kevin Hathorne from the urban entomology lab.

The infested tree has been removed and the Clemson team and Beavins are working with the tree service to properly dispose of the infested portion.

"At this point we have no other reports of Formosan termites in the Rock Hill area," Zungoli said. "There is often an overstatement concerning above-ground colonies of this termite. In my experience, true aerial colonies of the Formosan termite are very unusual and are most often found when there is an above-ground source of moisture."

In nature, termites are beneficial insects that serve an important function recycling dead trees into nutrients for the soil. They become a problem when humans build their homes or other buildings near a colony and termites infest the structure.

Several species of native subterranean termites are found in South Carolina. The Formosan species was introduced into the state in Charleston in the mid-1950s and is being spread as humans move infested materials, such as old railroad ties.

Formosan termites cause concern because their colonies can be much larger than those of native termites, sometimes including several million workers. While a timely response is important to control Formosan termites, Clemson entomologists advise that homeowners get estimates from three pest control companies before making a treatment decision.

For more information, visit the Clemson University entomology web site at http://entweb.clemson.edu/urban/index.htm.

END

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