From the San Francisco Chronicle:

A grape pest that has been the scourge of Napa growers for more than a year is the focus of eradication efforts in vineyards throughout the Sierra Nevada foothills for the first time.

The discovery of the European grapevine moth last month in two traps in Nevada County prompted state and federal agriculture officials to quarantine 103 square miles near Grass Valley. State agriculture officials say one moth was caught in a vineyard and the second in a residential area.

Nevada County becomes the ninth county affected by the quarantine, which restricts the movement of plants and equipment. More than 2,000 square miles of California's grape growing region is now affected.

The European grapevine moth feeds on grapes, plums, cherries and other fruits. The larvae it leaves behind can cause crops to rot.

Just as Napa seems to be getting the best of a grape pest that can spoil entire crops the tiny moth has popped up in yet another wine region.

For more, see: Grape pest quarantine extends to Sierra foothills