Linda F. Benedict, Mccown, Charles R., Ring, Dennis R., Morgan, Alan L.
Dennis R. Ring, Alan Morgan, Frank S. Guillot, Alan R. Lax and Charles McCown
The Formosan subterranean termite is considered the most important structural pest of the new millennium. It is more aggressive than native subterranean termites, and colonies may be greater in numbers reaching millions of termites. The Formosan subterranean termite builds above-ground carton nests and eats the centers of live trees. These characteristics contribute to the destructive potential of this invasive pest.
The Formosan subterranean termite was first discovered in Louisiana in 1966. Specimens of this termite were identified from Lake Charles in 1966 and from New Orleans in 1967. Taiwan is the native home of the Formosan subterranean termite. Two entry points were reported for the Formosan subterranean termite in the New Orleans area – the Algiers area across the Mississippi River from the French Quarter and near Camp Leroy Johnson on Lake Pontchartrain. Once the Formosan subterranean termite was introduced to the New Orleans area, it expanded its range, and the numbers of termites increased. The problem coincidentally increased in the French Quarter including historical buildings.
Management of Formosan subterranean termites became so difficult in the French Quarter that some pest management companies stopped treating for termites. The New Orleans Mosquito and Termite Control Board would receive 20 to 30 calls about swarming termites per swarm season from people in the Up per Pontalba Apartments near Jackson Square. One person reported sleeping in a pup tent inside his structure during swarm season to prevent termite alates from falling on him at night and waking him up. Buildings in the French Quarter experienced structural damage on an ongoing basis resulting in a continuous cycle of damage and repair. The situation was bleak.
In response to this problem, an areawide integrated pest management program was begun in the French Quarter with an objective of reducing the numbers of Formosan subterranean termites and potential for damage. This federally funded areawide program is a partnership among the LSU AgCenter, the U.S. Department of Agriculture’s Agricultural Research Service, the New Orleans Mosquito and Termite Control Board, area pest management professionals, and the Audubon Nature Institute.
In 1998, the program began with treatment of a 15-block area of the French Quarter. The strategy was to reduce damage caused by the Formosan subterranean termite by decreasing the numbers of termites through population management, eliminating colonies and reducing termite pressure. Treatments by pest control companies included nonrepellent liquid termiticides and baits. The remaining area of the French Quarter outside of the treated area was monitored to provide a comparison to the treated area. Monitoring methods included sticky traps strategically placed on light poles within 2 meters of all corners in the French Quarter. These traps collected swarming reproductive alates and helped determine the annual alate numbers in the area.
A second monitoring method was the use of in-ground monitoring stations. These stations, which were used to monitor termite foraging activity, were placed in contact with the soil in holes drilled through the sidewalks. Twelve stations were placed at regular intervals around each block in the initial 15-block area, and 44 additional stations were placed in the French Quarter outside of the test area.
In January 2002, this was supplemented with an additional 300 stations placed within the French Quarter outside of the test area. Stations were checked monthly and the presence or absence of termites was recorded. The treated area was expanded each year in 2002, 2003, 2006 and 2007. Inspections were also conducted on properties in the test areas. Aimed at determining the presence of Formosan subterranean termites, the inspections of these properties consisted of visual inspections and the use of infrared cameras. A pest management professional was contacted to treat any infestations located during the inspections.
Data collected showed that areawide management reduced termite numbers and activity in the initial 15-block area by 75 percent. A 50 percent reduction in the number of alates was also observed in other areas of the test within two years after treatment. In addition, a 50 percent reduction in the number of in-ground monitoring stations with termites was observed in the initial 15-block area. A similar 50 percent reduction in the number of in-ground stations with termites was observed in other areas after treatment.
In 2003, about 23 percent of the properties in the initial test area were found to be infested with termites. This percentage declined in each subsequent year, but increased in 2007 and decreased to zero in 2008. Declines in the percentage of properties found to be infested with termites were observed in other areas after treatment.
The number of complaints about swarming termites from people in the Upper Pontalba Apartments has dropped dramatically to about one per year. This further shows that the program has reduced the numbers of termites in the French Quarter. Visual inspections of trees and courtyards on these properties are being conducted to detect any termite infestations outside of the structures. Infested trees were treated by pest management professionals, and termites were not found infesting treated trees in subsequent inspections.
Results of the French Quarter program have shown a reduction in the numbers of Formosan subterranean termites using areawide integrated pest management. Reductions have been seen in the numbers of alates captured, percentages of in-ground stations with termites, infestations in trees, and numbers of swarms in buildings. Some isolated areas still exhibit high termite activity. These areas are being examined for termites through intensive inspections of structures and trees. Continued inspections, treatments and evaluations are needed to further reduce the numbers of Formosan subterranean termites.
The emphasis of the program has been on killing termites and management of termites throughout the landscape rather than simply applying insecticide barriers around structures. The program has shown that areawide management can be successful in reducing the numbers of Formosan subterranean termites. This program should be transferred to and adopted by other neighborhoods and cities.
Acknowledgements Rose Broggi, Chris Morel, Chris Dunnaway and Rita Riggio – LSU AgCenter; Ed Freytag, Barry Yokum, Perry Ponseti, Berry Lyons, Carrie Owens, Jamie Ward and especially Ed Bordes for the many hours of personal communication – New Orleans Mosquito and Termite Control Board; Pedro Levy, Ryan Solhjoo, Chris Florane, Ronnika Allen and Elena Khoutorova – USDA-ARS; pest management professionals for treating properties and cooperating in the program and property owners, tenants and property managers for allowing inspections and treatment of properties in the French Quarter.
Dennis R. Ring and Alan Morgan, both Professors and Extension Specialists, Department of Entomology, LSU AgCenter, Baton Rouge, La.; Frank S. Guillot and Alan R. Lax, USDA-ARS, New Orleans, La.; Charles McCown, Extension Associate, LSU AgCenter, Baton Rouge, La.
(This article was published in the fall 2010 issue of Louisiana Agriculture Magazine.)