Drywood termites often overlooked
Drywood termites are a major wood destroying insect that cost consumers many millions of dollars in damage and control. One estimate suggested Californians spend $250 million dollars a year on this insect. Do we have these termites in New Mexico? Yes we do. They have been rare and not often found in homes for many years. However they seem to be getting more common.
I have found drywoods in a half dozen homes this year and it is usually took three or four years to find that many. Possibly it is because inspectors aren’t looking in the right place and, in some cases, aren’t familiar with drywoods. There was one pest control person who inspected a home in the North Valley several years ago and didn’t find any subterranean termites but walked right over drywood fecal pellets without recognizing them. He cleared the house and when the drywoods were identified, he was responsible for treating the house and it was fumigated.
For many years the primary method of controlling drywood termites was to use sulfuryl fluoride (Vikane) as a fumigant. The house had to be wrapped and sealed and the gas injected. It was and still is a major inconvenience for homeowners as they had to do a lot to prepare for the fumigation as well as stay out of the house overnight. It was thought that once the house was cleared that the fumigant would dissipate harmlessly into the atmosphere. A recent study by the University of California at Irvine has destroyed that myth. It turns out that sulfuryl fluoride is a major greenhouse gas that can last about 30 years in the atmosphere and may last up to 100 years. This study can be found at (http://www.sciencedaily.com/releases/2009/01/090121144059.htm).
Also homes and commercial buildings are built differently now than when sulfuryl fluoride was in its prime. The homes made today are constructed much tighter to control energy and that can impede the flow of gas throughout the building leaving some areas untreated. This is one reason why fumigation has a higher re-infestation rate than some other treatments.
There have been other methods of control tried but most only allow spot treatments. Microwaves, heat, cold and electro guns are a few. Heat has actually progressed to where it is considered sufficient to control termites in the entire house. There is a lot of preparation needed for heat treatment and the time and labor cost is reflected in your bill for the treatment. It takes six to eight hours to heat a piece of wood internally to 125° Fahrenheit.
In addition, the pretreatment preparation required of the homeowner is extensive and, if not completed properly, heat can be extremely damaging to property, such as plastics, electronics, and many other items and there was at least one instance of a house exploding because of the heat and propane gas. I can’t recommend this treatment.
Drywood termites do not need soil contact. They live in dry, sound wood, usually near the surface. They get what moisture they require from the wood they feed on and from the water formed during digestion of that wood. Drywood swarmers generally enter your home at night through unscreened attic or foundation vents or through cracks and crevices between exposed wood. Drywood termites are most commonly recognized by their distinctive fecal pellets (piles) that are often the color of the wood they are feeding upon. The fecal pellets are kicked out of the wood by the nymphs (workers) through “kick holes” that are visible. Incisitermes minor is found in much of California where it is a major pest. It is also found in Arizona, Utah and here in New Mexico where the population seems to be expanding.
If you have a localized infestation that you can reach, then you can inject some Greenbug for Indoors into the kickout holes in the wood. You can also do this with furniture infested by drywood termites.
In most cases it is best to hire a professional who can treat for drywoods. They can treat the infested wood with Termidor and treat all exposed wood with a sodium borate to prevent further infestations. It is important to make sure that when you get a termite inspection, that the inspector knows how to inspect for drywood termites. If he or she doesn’t, hire someone else. Realtors should really be concerned about drywood termites in their home inspections.
If you have any pest questions or need a termite inspection, you can contact me at firstname.lastname@example.org, or by phone at 385-2820.