A group of UC scientists traveled to Chile recently to see firsthand vineyard damage caused by the European grapevine moth, according to an article in the Fresno Bee. The moth has been detected in California's Napa County, and is being actively tracked in the valley to determine whether the infestation has spread.

European grapevine moth was discovered three years ago in Chile. Because the pest develops from larvae to moth at a crucial time in the grape's growth cycle, its effects can be devastating.

"They have lost whole vineyards in Chile; not one grape was picked," UC entomologist Walt Bentley was quoted in the Bee. "It actually lays its eggs on the berry, and as the berries bloom little flower clusters, the larvae begins feeding on that. It is a voracious eater."

Napa County is world-renowned for its fine wines, but it may be the San Joaquin Valley that has the larger stake in the effort to keep the European grapevine moth at bay. Valley farmers produce nearly all of California's table and raisin grapes and, with 1.3 million tons of grapes for crush in 2009, lead the state's production of grapes for wine and concentrate.

A major European grapevine moth infestation could cost the industry millions of dollars in control efforts and lost sales to countries that block imports from areas with the pest, wrote Bee reporter Robert Rodriguez.

More information on the European grapevine moth is available on the UC Integrated Pest Management Web site.