State trappers are currently hanging brightly colored gypsy moth traps in trees, shrubs and other areas in a continuing effort to protect Washington's forests, producing agricultural lands and cityscapes from a destructive plant-eating pest.
The Washington State Department of Agriculture's (WSDA) annual gypsy moth trapping program will search for the invasive insect in every county of the Evergreen State.
Mike Louisell, public information officer for WSDA, said the agency anticipates hanging approximately 100 gypsy moth traps in Yakima County.
In comparison, King County will get more than 3,500 traps and Pierce County will get approximately 3,000 traps. The reason, he said, is because moth detections are much more prevalent in Western Washington.
"It is important to trap in Eastern Washington, but we haven't had a catch there for several years," Louisell said.
By the end of July, WSDA's 25 trappers will place nearly 20,000 small cardboard traps in residential neighborhoods and business districts, near ports and in rural areas. The traps will be checked every two to three weeks during the summer before being taken down in September.
John Townsend, state trapping coordinator for WSDA, looks forward to the annual trapping season. "If any gypsy moths are out there, we'll find them," Townsend said. "Our trappers play a key role in keeping permanent populations of gypsy moths out of the state. Trapping now will largely determine if eradication treatments will take place in 2012."
Townsend noted that the traps are non-toxic and contain a sex pheromone that attracts male moths. Inside the trap is a sticky surface similar to flypaper. The moth flies in and gets stuck to the inside surface-showing entomologists where a population of the pest may be developing.
On May 17, WSDA completed its gypsy moth eradication efforts at the South Hill Mall in Puyallup, a response that was based on catching seven moths at the site last summer and finding other evidence of gypsy moth activity in the area. Workers sprayed a biological insecticide on vegetation located in the northwest corner of South Hill Mall's parking lot. Three treatments were conducted over a period of several weeks, with crews spraying late at night using ground-based equipment. The timing of the eradication was based on the emergence of gypsy moth caterpillars to prevent their development into moths.
South Hill Mall and surrounding areas will receive additional traps this summer to help determine whether any gypsy moth caterpillars escaped the treatments. The site area will be officially declared eradicated if no gypsy moths are detected for two consecutive years. The Puyallup project was the first eradication treatment since eliminating a gypsy moth infestation in Kent in 2007.
The moth has been detected in Washington every year since 1977, but permanent populations have not been established because of the state's aggressive summer trapping and spring eradication efforts. Gypsy moths, which aren't native to the U.S., arrive in the Pacific Northwest on ships from foreign ports or by hitching a ride with people traveling from other parts of the country. Nineteen states in the East and Midwest are permanently infested with gypsy moths, causing extensive environmental and economic damage each year.
The gypsy moth is the worst forest pest ever brought into the U.S. In its caterpillar form, the pest attacks more than 500 species of trees and plants. The caterpillar quickly strips trees and plants of leaves, destroying some and weakening others so they are susceptible to plant diseases. The caterpillar destroys wildlife habitat, degrades water quality and triggers costly quarantines of timber, agriculture and nursery products.
WSDA's trap and pest detection programs include gypsy moth, apple maggot, sudden oak death, spartina, Mediterranean snail and Japanese beetle-all done to protect Washington's environment and to safeguard the agriculture, horticulture, nursery, timber and forest industries.