Thursday, June 25, 2009

Termites and Integrated Pest Management

In the United States there are four groups of termites of concern: subterranean (including the Formosan termite), drywood, dampwood and powderpost. Subterranean termites and drywood termites are the two general types. Subterranean termites "nest" in the soil and from there they can attack structures by building shelter tubes from the soil to the wood in structures. Subterranean termites cause more of the damage to homes and structures than drywood termites so will be my primary focus here. Termites will attack any material with cellulose, including wood, paper coated wall board, and paper (as in that treasured book collection that occupies the lower level of my home). Wood that is at least 30 percent water saturated provides enough moisture. Additionally, termites will find free-standing water such as condensation, rain or plumbing leaks and use this moisture as their main source for survival. Termites have been a part of the ecosystem for thousands of years and aid in the decomposition of wood, freeing the nutrients in the decaying material for reuse by other organisms. Termites rely on eating the cellulose found in wooden structures, furniture, stored food and paper. It is virtually impossible to reside anywhere in the United States without confronting termite damage at one point or another.

No technique, from the traditional, blast it with chemicals to the alternative strategies are 100% effective all the time. The most popular professionally applied conventional chemical treatments on the market are Premise (imidacloprid), Termidor (finpronil), and Phantom (chlorfenzpyr) range from slightly toxic to very toxic and vary in their solubility and affinity for soil. They are less environmentally persistent and more rapidly biodegradable, than previous generations of chemicals. This all means that they breakdown faster and do not last as long. In addition, Premise and Termidor kill termites more slowly than the "older" chemicals after the insects come in contact with the treated soil. Studies indicate that "contaminated" termites may pass some of these non-repellent chemicals to other members of their colony which increases the overall impact of the termiticide. There are steps a homeowner should take to make a house less ideal for termite invasions to minimize the use of chemicals. Ridding an infested house of termites or preventing termite infestation using the lest toxic method requires an integrated pest management approach that includes a series of methods fro preventing or managing pest populations based on an ecological understanding of the problem. The US EPA has developed their Pesticide Environmental Stewardship Program (PESP) to encourage these methods. The integrated pest management approach for termite control involves the following steps:

Inspection, detection and monitoring. The thorough inspections and periodic regular monitoring will help determine the location of any termite damage and its extent, signs of previous and current infestation. Research from the Entomology Department of University of Florida found that properly trained termite dog teams are the most effective termite inspectors. This is not a joke, but it is really funny to have your house inspected by a beagle. Termite Dogs can smell termites, through drywall, concrete, paneling and all other building materials.
Identification. The next step is to correctly identify the species found on-site. Ant and termites are often confused.

Determine treatment plan. There is a difference between finding termites and finding "conditions conducive to termite infestations". Both situations need to be addressed, but usually in different ways. Eliminating conditions favorable to wood-destroying pests, mostly moisture-related problems, usually means repairs or alterations to the crawlspace, elimination of water pooling locations and leaks in basements, crawlspaces or other parts of the house or the area around it. If inspection did not find any current infestation a monitoring program combined with these physical changes to the structure to discourage infestation in the long run. If signs of infestation were found, it is possible to spot treat infestation areas using the least toxic chemical. (This is probably borates for wood protection, and replacement of damaged wood. Any replacement wood elements should be with borates, and the infested wood elements removed from site.)

Treatment. The treatment options are bating with spot treatment and traditional chemical barriers. Termite baits use small amounts of insecticide to knock out populations of termites foraging in and around the structure. Some baits may even eradicate entire termite colonies. Termite baits consist of paper, cardboard, or other termite food, combined with a slow-acting substance lethal to termites. Regardless of which bait is used, the process is lengthy and four or five times as expensive as chemical treatment. Baits offer termites an easily accessed location to feed on wooden stakes, cardboard, or some other cellulose-based material. The toxicant-laced bait can either be installed initially, or substituted after termites have been detected in an untreated monitoring device. The more baits installed, the better the chances of locating termites. Planning, patience, and persistence are requisites for successfully using termite baits. This is a long term commitment.
Monitoring. After treatment it is essential to continue monitoring for termites. The success of the treatment method needs to be assessed and once elimination of the infestation has been accomplished, monitoring will detect further infestations as early as possible.

With termites it is important to eliminate all infestation before too much structural damage occurs. Chemical treatment with termiticides is the least expensive and fastest method of treatment for termites. The chemicals in use today are far less toxic than previous generations. If you are strongly opposed to the use of pesticides around your home you should go with a baiting system. Although conventional liquid termiticides reportedly pose no “significant” hazard to humans, pets or the environment when applied according to label directions, they are still toxic chemicals. With baits, the total amount of pesticide applied is small in comparison to the gallons upon gallons needed to achieve a thorough and effective soil barrier treatment. In addition, drilling through driveways, garage, and slabs may be required to create a complete and unbroken chemical barrier surrounding a house. Regulations prevent the application of most if not all termiticides within 50 feet of water well. Termite baiting requires fewer disruptions within the home and is protective of ground water and drainage systems compared to conventional chemical treatment. Installation and subsequent monitoring of bait stations generally does not even require the technician to come indoors. Noise, drill dust, and similar disruptions associated with conventional treatment are avoided, but the baiting process can take months, possibly a full year to eliminate infestations. Traps were quietly and neatly installed yesterday and will be scanned and entered into the system for regular inspections tomorrow. The beagle is scheduled to inspect the home at that time. Updates in my adventures in IPM process will follow.

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