Gypsy Moth Facts at a Glance

* Gypsy Moths were brought from Europe to the US in 1869 by a E. Leopold Trouvelot, who wanted to train the creatures to produce silk. Unfortunately, some of his insects escaped and began moving around in search of food.

* In the last 20 years, Gypsy moths have defoliated 58 million acres of forest in the Eastern United States. 1981 was one of the worst years, with over 12 million acres chewed. Since then the annual devastation has been fluctuating, with only 49,000 acres defoliated in 1997, but back up to 475,000 acres in 1999. Nobody is quite sure what causes this. Source: GM Digest, Morgantown, WV.

* Eastern forests have been known to recover from one or two annual gypsy moth infestations, but evergreens are more susceptible and often are destroyed by only one infestation.

* In the Eastern United States, infestations of gypsy moths are spreading at the rate of 21 kilometers per year along a 2,000 mile frontier from Canada to Georgia Coast.

* The moths we're concerned about in Seattle are Asian in origin. They are just like the European gypsy moth, which is the strain that has been eating its way through the Eastern U.S., except that the Asian moths can fly. The two types can interbreed. Some researchers are nervous about the European moths acquiring increased mobility through interbreeding.

* Bacillus thuringiensis (B.t.), which is what the Washington Department of Agriculture wants to spray on the trees of Magnolia and Ballard, occurs naturally in numerous species of agricultural and forest insects and is a natural component of the soil microbiota worldwide.

* One method of moth control is finding and destroying. The buff-colored egg masses contain 100 to 1,500 eggs, which are laid on the underside of tree limbs, bark, rocks and structures. The female moths sometimes lay their eggs on things that move, like campers, firewood and ship cargoes.

* Gypsy moth caterpillars are an extreme nuisance. Trees lose their foliage, caterpillars crawl everywhere, and their droppings rain from the trees. When disease kills large numbers of caterpillars, as often occurs, the stench is overwhelming. In some cases, people develop an allergy to the hairs of the gypsy moth caterpillars.

Here are a few of the 12,000 websites on the Internet related to gypsy moths:

Gypsy Moth in North America
http://gypsy.fsl.wvnet.edu/gmoth/

The Gypsy Moth Server at Virginia Tech
http://www.gypsymoth.ento.vt.edu/vagm.

The GM Digest website: USDA Forest Service gypsy moth suppression, eradication, slow-the-spread projects; also includes defoliation acreages and many links.
http://fhpr8.srs.fs.fed.us/wv/gmdigest/gmdigest.html.

The Washington State Department of Agricultural has no information about gypsy moths or spraying or other control methods on its website.

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