State biologists will announce in late December or early January if any insecticide spraying or other gypsy moth eradication efforts will be undertaken after one of the voracious pests was found in Sequim last summer, the second year in a row.
"It was a single catch site. The next step is to see if there’s any concern about what we found there and then to conduct additional trapping next year," said Mike Louisell, spokesman for the state Department of Agriculture.
"I don’t think it will be a significant issue but the whole idea is to nip the problem in the bud," he said.
If an eradication proposal such as spraying is announced, it would be conducted during the spring of 2009, Louisell said.
In June, biologists hung 25,000 tent-shaped cardboard traps from trees throughout the state and monitored them throughout the summer.
They found 21 gypsy moths at 17 sites, including three at Fort Lewis, two at Kent and two at Point Roberts.
Those sites are being inspected for additional evidence of gypsy moth activity, such as egg masses and pupal cases.
Sequim was one of 14 sites where only one moth was found and the only one in Clallam County. The next closest gypsy moth sites were Belfair, Poulsbo and the unincorporated community of Wauna southwest of Purdy in Pierce County.
"We spend 75 percent of our money for gypsy moth control on trapping to find introductions of moths, not infestations," said Department of Agriculture spokesman John Lundberg.
"The moths we trap may or may not be part of reproducing population dependent upon what the biologists find," he said.
If an area has multiple catches over several years, then they consider spraying or other treatment, Lundberg said.
All moths caught this summer underwent a DNA analysis and were found to be the European gypsy moth, according to a news release from the Department of Agriculture.
That is important because unlike its European counterpart, the female Asian gypsy moth can fly. The males of both species can fly. So the traps are baited with the scent of the female moth.
After hatching, the moth larvae are dispersed either by the wind or by attaching to something.
Then after the male and female have mated, the female European moth lays its eggs right there. Since the female Asian moth can fly to lay her eggs elsewhere, the potential for spreading an infestation is much greater.
The gypsy moth is one of the country’s worst forest pests. It attacks more than 500 species of deciduous and evergreen trees, has defoliated millions of trees and spreads relentlessly once established.
The moths came to the U.S. in 1869 under controlled conditions but eventually escaped and became permanently established in 19 states.
Gypsy moths normally arrive in Washington in the form of egg masses attached to outdoor articles, such as picnic tables, birdhouses and children’s toys brought here from infested states, primarily from the East Coast and upper Midwest. Some moths arrive on foreign ships docked at Washington ports.
The number of moths caught annually in Washington varies widely – ranging from a high of 1,315 moths in 1983 to a low of 17 in 2002. WSDA caught 24 moths at 10 sites in 2007, 75 moths at 18 sites in 2006 and 31 moths at 15 sites in 2005.
No permanent populations of the gypsy moth have been detected in Washington.