Editor’s note: On April 23, a task force of scientists, state regulators, extension agents and members of the Certified Pest Control Operators Association of Florida (CPCO) and the Florida Pest Management Association (FPMA) joined forces to eradicate the “Tree Termite,” Nasutitermes costalis, from Dania Beach, Fla. (To read more about this collaborative treatment effort, CLICK HERE). The task force used “drench” applications to eradicate this termite, which tunnels at or above ground level. The following article from Bob Hickman, market development manager, BASF Professional Pest Control, is an overview of the application procedures used for these two termiticides in the Nasutitermes costalis eradication effort, as well as a look at the earlier use of both products for control of this invasive species.
In 2001, a non-native termite species, Nasutitermes costalis, was first identified by University of Florida entomologist Dr. Rudolf Scheffrahn, after its discovery during a routine home inspection in Dania Beach, Broward County, Fla. Scheffrahn recognized the termites as a common Caribbean species – though the first of its kind ever found in the U.S. He speculates that Nasutitermes costalis had been breeding in South Florida approximately eight years prior to their discovery.
In the two years since their detection, Scheffrahn and the Florida Department of Agriculture have closely monitored the dissemination of Nasutitermes costalis within a 50-acre area of Dania Beach. In that time, members of the Tree Termite Eradication Task Force – a group representing the Florida Department of Agriculture, the University of Florida, local County officials and Florida pest management professionals – have worked to study the species, planning for the eventual eradication of the invasive termite.
Nasutitermes costalis is an arboreal termite species, building nests within the branches and at the base of trees and other structures. Because of its aboveground foraging activity, conventional termite treatments are ineffective in controlling Nasutitermes costalis. Instead, researchers from the University of Florida Institute of Food and Agricultural Sciences (IFAS) worked with newer non-repellent liquid termiticides – many of them already labeled for above-ground termites – that could be applied around and directly to the termite nests.
In lab testing conducted by IFAS, two such termiticides were chosen for use in the eradication effort – Termidor® termiticide/insecticide (fipronil) and Premise® termiticide (imidacloprid). The following is an overview of the application procedures used for these two termiticides in the Nasutitermes costalis eradication effort (April 23, 2003), as well as a look at the earlier use of both products for control of this invasive species.
Early Control Efforts – Dania Beach, FL, May-August 2001. The first infestation of Nasutitermes costalis was discovered in May 2001 at a home in Dania Beach. A full subterranean termite treatment of Premise at the labeled rate was applied for this initial infestation. An additional Premise treatment was made in December 2002 following the discovery of a re-infestation at the original site.
In August 2001 a Nasutitermes costalis infestation was discovered on the property adjoining the original termite infestation. Termidor was applied by an Orkin applicator as a 0.06% treatment at an experimental rate of 4 gal./10 linear ft. Under the supervision of Scheffrahn, an experimental application was made around the perimeter of the home, to the surface of the soil with the intent to thoroughly treat the upper 2 inches of soil – an application similar to the Termidor ant label perimeter treatment, but differing in the volume of product applied. As of May 2003 – nearly two full years after the initial treatment – no re-infestation of the Termidor treated site has been found.
Field Testing of Termidor for Nasutitermes costalis – Dorado, Puerto Rico. Field trials of Termidor for control of Nasutitermes spp. were conducted in August 2001 at the Hyatt Dorado Beach Resort in Dorado, Puerto Rico. Termidor was applied as a 0.06% surface treatment only at a rate of 4 gal./10 linear ft., through a variety of treatments, including direct treatments to active termite nests, at the base only of trees with active termite nests, and on the surface of soil next to exterior foundation walls and slabs.
The goals of these treatments were twofold – first, to confirm that direct-to-nest treatments using Termidor would effectively kill tree termite nests; and second, to find out if Termidor applications sprayed only at the base of trees with active foraging tubes and an overhead nest would kill the nest via the Transfer Effect™.
Direct treatment of the nests resulted in 100% kill over the entire monitoring period (12 months). The base-only treatments proved to be just as successful. Within four months, 9 of 10 tree termite nests treated using base-only treatments were controlled – including nest kill. Where nests were accessible, all activity in both tubes and the nest was confirmed ceased within two months after treatment, and remained so throughout the study. Where nests were inaccessible, termite activity in foraging tubes ceased in all but one treatment site.
In addition, a surface treatment of a 6-inch band of soil next to exterior foundation walls and slabs – similar to the applications that were ultimately made in Dania Beach – resulted in 100% control of activity throughout the study.
Nasutitermes costalis Eradication Effort – April 23, 2003, Dania Beach, Fla.* In a concerted effort, certified pest control professionals used non-repellent termiticides in an attempt to eradicate Nasutitermes costalis on April 23, 2003 – approximately one month prior to the termite’s anticipated swarm season.
Termidor was mixed at a concentration of 0.125% active ingredient, while Premise was mixed at a concentration of 0.1%. A Florida Experimental Use Permit was issued for each product; use directions specified application to termite nests and foraging areas with active tubes.
Initial batches of 200 gallons were mixed in separate commercial application vehicles acting as nurse tanks. A separate 50-gallon batch of Termidor was also mixed. A total of 380 gallons of Premise application solution was applied, while 450 total gallons of Termidor was applied. infested area in Dania Beach was divided into 10 treatment sections – Termidor was applied to 5 of these sections, with Premise applied to the 5 other sections.
Tracker, a commercial blue dye from Lesco Corp., was added to the application mixtures to avoid over- or missed application of the termiticides.
The termiticides were applied in a circular pattern over and around the nest, active tube or foraging area. Applications achieved uniform coverage at a rate of not more than 1 gallon per 10 square feet. The application wand was also inserted into each nest or mound, where an amount equivalent to not more than 1 gallon per ten square foot was applied. At two locations, nests, mounds, or tubes were within twenty-five feet of open water. At these locations, the applications were made so as to prevent any direct application of spray material to the water. Application to the nest or tube itself was done so that material did not run off of the nest or tube into water. No application was made to trees, stumps, bushes or any other object that extended over water.
In addition to the Termidor and Premise applications, two trailers and two boats were fumigated using Vikane® gas fumigant.
Treatment Assessment. The first of two follow-up assessments of the treated area will take place approximately 60 days from the initial application date. At this time, three sections that had seen high levels of Nasutitermes costalis infestation will be examined. A more complete survey of the treated area will be conducted in fall 2003.
The author is a market development specialist for BASF Professional Pest Control, where he works with cooperators and BASF Partners in the Southeastern U.S. and Puerto Rico. In 2001, Mr. Hickman supervised field-testing of Termidor in Puerto Rico for control of the Nasutitermes costalis. He has worked with the Tree Termite Eradication Task Force throughout the eradication effort.
* Source: Dwinell, Steve. Tree Termite (Nasutitermes costalis) Eradication Effort Progress Report; April 29, 2003.
