Syrah grapes ailing in California

SAN FRANCISCO, Dec. 10 (UPI) -- Forty percent of Syrah grapes in California's wine-loving Sonoma County are ailing and scientists said they suspect a virus caused the mysterious ailment.

French scientists have researched what they call "Syrah Decline" for six years and haven't found the culprit, though they said they believe it's a virus, San Fransisco's KCBS reported. Symptoms include stunted growth in spring, vines swelling at the base and red leaves in summer.

"Vintners are taking this on a case-by-case basis. So if individual vines are declining on a certain vineyard, then obviously they have to be pulled out and replanted," said Rhonda Smith, a Sonoma County viticulture farm adviser with the University Cooperative Extension, told KCBS.