When Do You Need Termite Treatment?

Prevention

First, seal termites out. Cover exposed wood with paint or sealer. Caulk cracks and crevices. Screen windows and vents.

Second, treatment of exposed wood with borates or boric acid provides long term protection against infestation.

Don’t have wood in contact with soil.

Cover exposed wood with paint or sealer.

Remove wood debris from your yard.

Plant trees away from house, and prune away vegetation that provides a bridge to the house.

Ants are predators of termites. Do not kill ants that are not causing a nuisance problem in the house.

According to Sheila Daar and William and Helga Olkowski, " The most permanent, most effective and safest treatment of the problem at the most reasonable cost may require a careful integration of activities carried out by the homeowner and a number of experienced professionals [ such as carpenters] from more than one company." ²

These are the nontoxic or least-toxic options that may be incorporated into your strategy:

Removal or repair of infested wood. For a small infestation, this may be all that is needed.

Heat: This involves tenting and heating either the whole structure or just a part of it up to 140 degrees F^o, a temperature that will not harm the structure. A test of termite eradication methods at UC Berkeley in 1996 resulted in a 100% mortality of termites in naturally infested wood boards treated with heat.³ Care is required to remove all household items that may be damaged by heat, such as electronic equipment.

Microwaves: this is a spot treatment method that also kills the termites by applying heat. The researchers cited above got a 100% mortality rate with this method as well, applied to naturally infested boards. Other studies have had varying success rates. House damage may include warped wood and wood burns.

Cold: cold treatment with liquid nitrogen is a spot treatment method whose effectiveness ranged from 74 to 100% in the above tests, depending on the dose used. This can be an effective method for inaccessible areas, as nitrogen is injected through small holes drilled into the walls. Frost formation within the house may damage some wall coverings. Drill holes must be repaired.

Electrocution: Called Electrogun, this is a spot treatment using volts of electricity, which kills termites in exposed wood. Mortality in the above tests was 95% four weeks after treatment in naturally infested wood. Drill holes and minor wood burns may result from the Electrogun method.

Borates: Borate salts or boric acid can be injected into wood as a treatment or applied to wood surfaces as a preventive measure. Borate dust may be used in wall voids as well. Borate foam is another form of borate that may be applied as a spot treatment. Depending on the product and treatment method, borates may act as a contact poison or a stomach poison. Borates should not be used on wood in contact with soil, as they are water soluble and will leach into the soil. Tim-Bor, Bora-Care, Jecta, and Impel are some brand names of borate products. Ethylene glycol may be added to liquid formulations of borates; this substance increases the penetration of the borate into wood but may be a problem for chemically sensitive individuals.

Fungal pathogens: BioBlast is the trade name of a method that utilizes a fungus that is deadly for termites when sprayed onto the infested wood.

Limonene or other citrus derivatives. Limonene has been used successfully as a pet flea control agent, and is now being applied to termite control. No information was found regarding the effectiveness of this method, whether it provides residual protection, or to what extent it is found in the indoor air of structures treated with it.

Neither borates nor fungal pathogens was tested in the Lewis-Haverty study cited above, so their effectiveness cannot be directly compared to the other drywood termite treatment methods. Both of them provide some residual protection against reinfestations, whereas fumigation, heat, cold, and Electrogun do not.