The first grapes of the season were picked from vines early this morning near Rutherford that will be used to make sparkling wine.
Winemakers say this year's harvest is a very good one.
"What we're not getting in quantity, we're getting in quality – very early flavor development, bright acidity. We're looking at a very nice vintage," Mumm Napa winemaker Ludovic Dervon told KCBS.
Mumm Napa was the first winery in the valley to harvest their grapes.
Sales of sparkling wines are growing in California, and across the world. Dervin says California's grape quality rivals that of France's Champagne region, where the weather can be fickle.
"What you will see there is ups and downs in quality; a good year and bad year," Dervin said.
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