Home > Life in Japan > Features
  print button email button

Sunday, Sept. 30, 2001


A plague upon your house

Staff writer

Insects aren't everyone's favorite animals, especially when it comes to those such as cockroaches, termites and wasps that frighten us as well as potentially harm us and our environment.

Spraying supporting posts prevents termite infestation and eventual house destruction.

Most people would do anything to rid their house of such pests. The Japan Pest Control Association estimates that through their 41 centers nationwide in 1999 they gave 20,365 consultations to anxious members of the public. Almost 56 percent of these concerned wasp infestation, with rats and mice ranked second, termites third, cockroaches fourth, fleas fifth and mites sixth.

The most serious of these unwelcome houseguests is the termite, regarded as Japan's most destructive pest as it can invade almost the entire house, from floorboards and tatami mats to walls and furniture. They especially inhabit places that are damp, which at certain times of year can mean almost anywhere, given Japan's often humid climate.

The Formosa subterranean variety of termite can truly bring the house down.

There are two species of termite in Japan: the native subterranean termite (Reticulitermes speratus) that can be found throughout the country apart from northern Hokkaido, and the Formosan subterranean termite (Coptotermes formosanus) that inhabits the coastal areas of Kanagawa Prefecture, the Nansei and Ogasawara islands, and Kisarazu and Tateyama, Chiba Prefecture.

Japanese subterranean termites are chiefly visible during the swarming season in spring when they fly during the daytime, whereas their Formosan cousins fly in the evenings of June and July.

When not swarming, termites habitually avoid light -- in Japan they are termed ankoku no jusha or (dwellers in the dark) -- and thus their activities generally go unnoticed. This means that considerable damage can be done before their presence is detected.

As termites often enter buildings through the earth, they first cause damage to lower structures such as foundations and floor posts. Upright beams of houses are progressively loosened in their postholes. Once damage has spread that far, buildings are at risk of collapsing during an earthquake or typhoon.

In order to protect against attack by termites it is sensible to inspect for their presence from time to time and take swift action if they are discovered. Ideally, prompt detection of termites enables preventive measures to be taken before they even begin to attack a threatened building.

"Termite control can be conducted more easily -- and inexpensively -- when a building is first built, as then it is not necessary to delve deep under the flooring," said Tokuaki Hyoma, director of the Japan Termite Control Association. Because crucial structural components such as floorboards and beams may have been weakened by termite activity, it is dangerous for nonprofessionals to attempt to exterminate them; the association suggests contacting professionals to carry out any necessary work. Asante Inc., a member of the association, places importance on comprehensive below-floor maintenance. The company employs two methods of termite extermination. One way involves spraying the ground with chemicals; another technique is to chemically impregnate wooden components under the floor, such as the foundations or supporting posts. The cost of such a preventive treatment is around 10,000 yen per tsubo (about 3.3 sq.-meter space), including followup checks. A five-year guarantee is usually attached.

For added peace of mind, use both methods. A ventilating system can even be installed to dehumidify the air circulating beneath the floorboards.

Takayoshi Nishimura, head of customer consulting at Asante, says that the company uses mainly pyrethin sprays containing active pyrethroid, believed to be less toxic for humans than chemicals such as organo phosphates.

"At the moment, there is a shift toward using sprays with less toxicity," said Tsuyoshi Yoshimura, an associate professor at Kyoto University who specializes in the control of wood deterioration and who also conducts chemical research for the association. "It is important for consumers to choose the procedures they like and to be able to say what kind of chemicals they would like used," he added.

Here are some tips on the prevention and extermination of some other pests that may bug us in daily life:

Cockroaches: These eat food, dirt or animal excrement, and their habit of walking over uncovered food or plates is pretty disgusting because, like flies, you never know where they've been. Normally, these creatures do not survive the winter, but beware that some can find refuge in a concrete structure with a heating system. For prevention:

Store food or kitchen refuse in a container with a lid.

Clean warm places such as the back of gas cookers or refrigerators at frequent intervals.

Keep kitchen space, cupboards and drawers as clean as possible.

For extermination:

Apply pyrethin sprays, organo phosphates or use aerosol insecticide.

Place poisonous bait laced with boric acid.

Wasps and bees: There are about 300 different kinds of wasps and bees in Japan, but those that sting humans are hornets, long-legged wasps and honey bees. Hornets tend to be aggressive, but long-legged wasps do not attack unless their nest is disturbed. Honey bees rarely attack people. These insects are sensitive to things that move right and left, but not to things that move back and forth, so you should squat down and quietly step backward.

In some prefectures such as Aichi Prefecture, local public health centers offer consultation on hornet control. In cases where a hornets' nest is located on the outside of a house and thus is a danger to the public, extermination is usually performed at no cost by employees of the center.

If you are stung, apply ice to the affected part and use tweezers to remove the poisonous sting. Apply antihistamine ointment, and seek medical advice in the event of severe itchiness or swelling.

Mites: Mites (arachnids, not insects) are so small they normally go unnoticed, but they live in almost all homes and recent medical research has identified them as a potential cause of asthma attacks or allergic reactions.

For prevention:

Vacuum the floor and ventilate rooms as much as possible.

Try to avoid temperatures of 25-28 degrees and humidity of more than 60 percent.

The most effective way of exterminating tatami mites is to air matting outside for more than four hours on a day when the temperature is over 30 degrees.

Back to Top

About us |  Work for us |  Contact us |  Privacy policy |  Link policy |  Registration FAQ
Advertise in japantimes.co.jp.
This site has been optimized for modern browsers. Please make sure that Javascript is enabled in your browser's preferences.
The Japan Times Ltd. All rights reserved.