We noticed this brightly colored box hanging from a tree in the Lake Ballinger neighborhood, a reminder that the Washington State Department of Agriculture’s statewide annual gypsy moth trapping program is underway.

According to the Department of Agriculture website, 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, production agriculture and cityscapes from a destructive plant-eating pest.

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 website said. The traps will be checked every two to three weeks during the summer before being taken down in September.

“If any gypsy moths are out there, we’ll find them,” said John Townsend, state trapping coordinator for WSDA. “Our trappers play a key role in keeping permanent populations of gypsy moth 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.

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 moth, 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.