Termite Control: Results of Testing at the U.S. Forest Service
Liquid termiticide treatments to soil continue as the most widely used method to protect wooden structures from attack by both native and Formosan subterranean termites, and have been the mainstay of the pest control industry for decades. The Wood Products Insect Research Project was located at Gulfport, MS, until 1995, and is now headquartered on the Mississippi State University Campus. However, field tests are still installed and maintained at the primary research sites in Arizona, Florida, Mississippi (Gulfport), and South Carolina, as well as at the Formosan subterranean termite research site on Midway Island. A new test site has also been established on Puerto Rico, and limited tests are still conducted at the U. S. Army Tropic Test Site in the Republic of Panama. Several termiticides are currently registered by the U. S. EPA for use under and around wooden structures (Table 1). Two additional pyrethroids, cyfluthrin and deltamethrin, have been effective in field tests and may soon complete EPA registration. Five years of Premise tests were completed during 1997 and results were reported in the April 1998 issue of Pest Control (please refer to this article for details). In Forest Service field sites, the ability of subterranean termites to penetrate termiticide-treated soil to attack pine blocks or boards is evaluated for at least five years, but tests often run much longer. Chlorpyrifos (Dursban, Equity, Tenure, Cyren, Navigator), cypermethrin (Demon, Prevail), fenvalerate (Tribute), and permethrin (Dragnet, Torpedo, Prelude) field tests were initiated from 1967 through 1980. Bifenthrin (Biflex),. cyfluthrin (Tempo), deltamethrin (EC formulation), and imidacloprid (Premise) tests were initiated in 1986, 1987, 1988, and 1992, respectively. Deltamethrin (DeltaGard TC; grEvo) will be marketed as a suspension concentrate with a planned general use rate of 0.125%, or at 0.25% for use under difficult-to-treat situations. These tests determine the years-of-effectiveness of currently marketed and potentially new termiticides as treatments to soil under long-term field conditions.