National Formosan Subterranean Termite Program

Program Info > Approaches

Approaches to Fighting the Formosan Subterranean Termite

This multi-agency termite control project will be unlike any previously attempted. A variety of control methods will be tried, many of them complementary to one another. The project will involve a wide range of scientific disciplines, from entomology to biochemistry--but everyone in the community also has an important role to play.

Speaking in Termite Tongues: Chemical Communication

Many insects "say it with pheromones"--naturally produced chemicals that serve as sexual signals--when it's time to mate. But others make war, not love, with their body chemistry. Some termites' salivary glands contain irritants or toxins that deliver a message of "Get lost!" rather than "Come hither." Other chemicals signal when a group member has found food. The chemical messages of bees and wasps are much better understood than termite talk. Knowing more about termites' chemical lingo may help us give them the word that they're not welcome in town. Or we may lead them on--out of our communities and somewhere where they can't cause trouble.

"Hi, Remember Me?": Natural Enemies from Back Home

The Formosan subterranean termites' natural foes from their native lands didn't join them in the New World. But these enemies--possibly bacteria, fungi, or insect predators--could prove invaluable in keeping termites in check. Naturally, such organisms would have to be extensively evaluated to ensure they pose no threat to people, pets, livestock and plants in our community. But if a bacterium like Bacillus thuringiensis or a fungi like Metarhizium anisopliae can make the grade, they could be important allies in this termite battle. And there could be other natural enemies--currently unknown--that will be safe for our area, but bad news for the termites.

Steeling Ourselves Against Infestation: Physical Barriers

It's been demonstrated that stainless steel mesh provides an effective barrier against termites. Australian researchers have suggested incorporating these barriers into buildings at the design and construction stages. Other reports show stainless steel is 100 percent effective at blocking termites' advances over a three-year period.

It's also been recommended that every building have at least six inches of clearance above the foundation where termite shields made of stainless steel, plastic, metal or concrete can create a barrier. Builders also could deter termites by keeping any wooden foundation structure from extending through the concrete foundation and avoiding foundation cracks. Scientists may also find new materials or new building strategies that prove economical and effective.

Bait and Switch: Better Termite Control through Chemistry

Getting rid of termites with chemicals is nothing new. One promising approach: A toxin is mixed with bait, combining something termites crave with a little lethal lagniappe. Such systems are commercially available today. These systems use wood blocks to monitor for the presence of termites. When they are found, the wood is switched with a toxic bait which the termites eat and take back to share with their nestmates, thus killing many termites or even the entire colony. In the 1930s, Paris Green, an emerald-colored toxin, was shown to be lethal to termites when mixed with food.

Today we know more about the effects of chemicals on public health and the environment. The chemicals used in the baiting systems are much safer than most of the soil termite killers that have been used to protect homes. The chemicals used today are more specific for termites. In some systems, the chemicals are only applied when termites are present, making them environmentally safe.

The products were developed in response to EPA's 1988 ban on the use of powerful organochlorines, one of the top tools to fight termites in years gone by.

One class of weapons will likely become even more important in the future: insect growth regulators, the same chemicals that naturally launch insects into adulthood. These chemicals can be manipulated to send their signals at the wrong time and disrupt the termites' normal development, providing a very effective and safe control.

Another alternative is slower-acting toxins that, unlike organochlorines, break down quickly and pose little threat to humans. Commercial products of this type are already on the market. What's lacking is a side-by-side comparison of their effectiveness. There are also chemicals that seem to make wood less appetizing to termites. New research could tell us which product is most effective or help find new chemicals that might be even safer or better for termite control.

Bugs' Lunch: How Nutrition Knowledge and Better Sanitation Help

Researchers will also conduct complex chemical analysis of the vitamins, minerals, proteins, fatty acids and carbohydrates termites require. The scientists aren't trying to bring the termites to optimal health; rather, they're searching for the insects' nutritional "Achilles' heel."

We already know some of their dietary weaknesses. All termites avoid a lack of moisture; that's why they thrive in coastal areas. Without constant moisture, the termites can't thrive as a colony and many would die.

Keeping leaky roofs fixed and gutters clean would help by keeping wood building structures dry. Construction practices in the French Quarter make moisture control very difficult, but it's important there, too. Moreover, the insects need a specific balance of nutrients to maintain optimal health. If scientists can pinpoint what attracts and stimulates the termites to feed, we could develop even better baits causing the colony to crash.

Keeping An Eye on Invaders: Geographic Information Technology and Monitoring

With all of these approaches, the ultimate question is, "Does it work?". That means researchers must be able to monitor the termites, both in the laboratory and at infestation sites. If you're seeing swarms of termites, odds are the structure has already suffered damage. Detection of termites inside a wall or underground requires sophisticated technology and instruments.

One of these devices can detect termite activity by eavesdropping on the sound of termites chewing. But acoustic detection is expensive and labor-intensive, and can only detect the termites if placed very close to them. Development of new technology with greater sensitivity would allow us to "see" the termites inside a wall or find very small colonies when they are easier to control. These instruments would allow us to put toxins right where the termites are.

Researchers might install "mini-walls" with plexiglass peepholes to monitor colony behavior inside an infested building. That also would allow scientists to check the termites' response to new controls. These transportable pseudo-structures could also be used to capture the insects and take them back to the laboratory for more study.

Another possible research tool: a computerized mapping system that enables researchers to follow the spread of colonies--and see for themselves what factors are associated with most infestations. Being able to predict where the termites might be would allow for more effective monitoring. Another use of mapping technology is to determine which controls have the greatest success.

For more information, contact the Southern Regional Research Center, Agricultural Research Service, USDA, New Orleans, La. 70179. Telephone: (504) 286-4444.