SPOKANE — The state is setting traps to learn if four species of moths that attack wine grapes have moved into Washington.
Washington is the second-largest grape-growing state in the nation, but vineyards could be damaged if certain species of destructive moths appear.
The state Department of Agriculture said it will place up to 1,000 traps this month, mostly in central Washington. Traps will be placed in most of the 13 major wine-grape growing regions. The traps will be checked every two to four weeks during the summer.
The European grapevine moth was found for the first time in the U.S. in 2009 in the Napa Valley of California.
Mike Klaus, a Department of Agriculture entomologist and survey coordinator, said none of the four destructive moth species have been detected in Washington so far.
“The goal of the survey is to protect Washington’s grape industry by preventing the establishment of these invasive moths,” Klaus said. “If any of these grape pests were to become established here, they could pose a serious threat to our grape and wine industries.”
The four species of destructive moths are European grapevine, European grape berry, Grape tortrix and Grapevine tortrix, he said.
“We greatly appreciate the focus of the grape-pest survey from WSDA,” said Vicky Scharlau, executive director of the Washington Association of Wine Grape Growers. “The damage potential from these pests … is a huge concern to us.”
The European grapevine moth was found for the first time in the U.S. in 2009 in the Napa Valley of California. The pest has since been found in several other California counties, and some California growing regions are under quarantine.
If any of the targeted moths are found in Washington this summer, state agriculture officials may place more traps in the area in an attempt to find the center of the infestation, the Department of Agriculture said.
The Department of Agriculture will also resume a limited survey for grape phylloxera, an aphid-like pest that attacks grape roots. Washington State University and the Department of Agriculture as recently as 2002 had detected grape phylloxera at a few locations in eastern Washington vineyards and backyard grape plantings.
But surveys for the pest have not been conducted in the state since 2002. That’s because control of grape phylloxera is costly and requires many pesticide applications over several years. Planting resistant rootstocks has been the primary control measure. However, new types in California are known to attack previously resistant rootstocks.