Ah, these Californians.
First they take some prime real estate in the San Francisco Bay area. Then they build a custom home. And then they give it to . . . termites?
Well, the house wasn’t exactly a gift. It was part of a scientific experiment on the UC Berkeley campus. The termites were placed in the house in waves, and each wave was attacked by a different method of extermination--heat, cold, electric shock, microwave, fumigants--to see which works best.
The researchers dubbed the house “Villa Termiti.”
Cute idea, and a real media draw. When the first body counts were announced two months ago by the co-investigators at Berkeley and the U.S. Forest Service, reporters rushed
to the battlefield--even CNN, as everyone involved likes to point out.
The war was such fun, the conclusions were almost buried. The data proved that nontoxic “alternative” methods can kill drywood termites. But it also showed that for a real no-survivors, no-escape victory, nothing beats, or even equals, whole-house fumigation.
After the media blitz, California homeowners swamped Berkeley’s extension office with requests for more information on the experiment. “I love my work but given the demands and the lack of resources, the attention has gotten to be a drag,” said entomologist Vernard Lewis, Ph.D., one of the principal investigators.
The interest is understandable. Drywood termites are a big problem in California. Each year, Californians spend an estimated $300 million to $400 million to fight termites, most of it on drywood rather than subterranean termites.
The study was undertaken, Lewis said, to try to answer the questions of both consumers and the industry about the effectiveness of alternative termite treatment methods as well as traditional fumigation techniques.
Vendors of alternative methods have been marketing nontoxic treatments--freezing termites right in the walls with liquid nitrogen, roasting them, zapping them with “Electro-Guns.” These are appealing because they seem environmentally benign, impressively high-tech and there’s no telltale Baggie over the house advertising the presence of termites and the absence of occupants.
But do the alternatives really work? The consumer can’t tell. The only visible evidence of live termites is little piles of droppings; there’s no evidence of termite death.
The study of alternative methods includes projects at both UC Berkeley and UC Riverside. It is funded by grants from the state’s Structural Pest Control Board and donations from the pest control industry.
“Pest control operators need to have as many tools available to them as possible, because people may have a real or perceived objection to pesticides,” said Harvey Logan, executive vice president of the Sacramento-based Pest Control Operators of California. “We hoped the study would show alternative methods safe and effective, that they worked.”
Villa Termiti, built at Berkeley’s Forest Products Lab, is really only a 20-by-20 foot room (the size of a two-car garage) finished in gray stucco with a green shingle gabled roof.
The villa has four identical sides, each with a door and windows, and an attic and crawl space. It has no insulation, no pipes, no heat and the main room is just drywall over framing. (The drywall has already had to be replaced three times over the months of testing.)
The house was ready for occupancy last August, but the termites weren’t just ushered in and allowed to choose their own rooms. They were hand-placed in Douglas fir boards that were divided into three “galleries” with 25 termites in each gallery, for a total of 75 termites per board.
Then, Lewis said, the boards “were randomly placed in the villa. The studs were exposed, the boards were affixed to the studs and the drywall was put back.”
The villa was treated 11 times with six drywood termite eradication methods--two fumigants, heat, liquid nitrogen, microwave and electrogun. Pest control operators specializing in each method performed the treatment, with the exception of the liquid nitrogen method, which researchers applied because Tallon Termite & Pest Control, whose Blizzard System advertises that “We freeze their little buns off,” refused to participate in the study.
Four of the six methods were full-house treatments, involving 48 boards (and 3,600 termites)--12 in the attic, 24 behind the drywall, 12 in the sub-area. The microwave people couldn’t do the sub-area, and the liquid nitrogen was put only into the walls. In all cases, the boards were pulled out and the survivors counted within a couple of days and carefully put aside, Lewis said, because “if you leave them too long, the ants find them.”
--Sulfuryl fluoride (“Vikane”), a fumigant gas injected into the tarp-wrapped villa: No termites survived, no damage to structure.
--Synergized methyl bromide (“MAKR”), a fumigant gas cut by carbon dioxide and injected into the tarp-wrapped villa: No termites survived, no damage to structure.
--Heat, in which propane heaters in the tarp-wrapped villa raised the internal temperature of the wood to 120 degrees (and the room air to 187 degrees): About 35, or 1% of the 3,600 termites survived, those closest to the concrete foundation. Minor warping of some boards.
--Liquid nitrogen (292 degrees below zero), sprayed into the wall voids of the villa’s main room: No termites survived. Minor warping of drywall panels. Holes drilled into the drywall for the procedure required repair.
--Microwave, over 500 watts, administered through a funneled device the size of a toaster oven set on a tripod close to the wall. Almost 8% of termites survived. Some boards severely burned.
--Electric shock, administered by electrogun through pinholes drilled in the drywall: About 50% of the termites survived, but another 30% expired over the next several weeks. Pinholes in the drywall required repair.
“The bottom line is obviously that (all methods) kill insects,” Lewis said. “But if you’re looking for 100%, some fall short, and in the field, they probably fall shorter yet. If you want 100%, you’re in the chemical area.”
Spot treatment might be good enough, but only if all the spots of infestation are located, which can be difficult. The UC researchers used acoustic detection equipment not yet commercially available to pick up signals that humans can’t hear--in this case, the sound of wood fibers being torn by tiny mandibles. “If the industry had the tools I have, maybe they could use spot techniques,” Lewis said. “And still, if I picked up termites in three or four different areas of a house, I’d fumigate.”
At least, he added, “I now have data that says: first, if you treat for termites, treatment methods are not always 100%, but second, even with the Electro-Gun, 80% are killed. Given all that, someone (who is) chemical-phobic could make a decision.”
The industry reaction to the news from Villa Termiti was mixed. Jay Tallon, owner of Tallon Termite, although “tickled pink by the conclusions,” criticizes both procedure and results.
“These people didn’t have the foggiest notion of how much (nitrogen) to use,” he said, having refused to give them the information. And he thinks the conclusion bears out his suspicion that the purpose was “to come out and (show) fumigation still the best way to go.”
The Pest Control Operators’ announcement of the results (“Some Non-Chemical Termite Treatments May Fall Short in Their Claims, Study Finds”) seems to support his assertion. But, Logan said, it was “intended to be realistic, not negative.” The association considers the study “somewhat encouraging,” but “basically a laboratory experiment, using more of the (alternative) product than what’s used in the field.”
But there is support in the industry for the nontoxic techniques.
“The industry would accept the fact that all alternative methods are effective spot treatments,” said Carl Doucette, vice president of American City Pest Control in Lawndale and an industry member of California’s Structural Pest Control Board. “The problem is they guarantee the whole house.”
So far, there aren’t many vendors using alternative methods.
While Villa Termiti was being alternately infested and attacked, researchers at UC Riverside examined 20,000 termite inspection reports filed in three Southern California counties. They found that nontoxic alternatives were used in fewer than 10% of termite control jobs. Most consumers stick to conventional methods--either spot treatments with chemicals or whole-house fumigation.
The Villa Termiti study isn’t definitive, but it’s a first and a useful step, the researchers said. The public response to it certainly proves that the question of drywood termite treatments in general and alternative methods in particular is of wide interest. Further study is needed, Lewis said, with more resources and more manpower, so he and his fellow entomologists can get off the phones and back to work.