(TDB) - Grape vine virus Red Blotch could be as damaging as phylloxera to Californian vineyards, believes Bruce Cakebread of Napa’s Cakebread Cellars.

Following a tasting in London on Tuesday this week, Bruce Cakebread discussed some of the issues facing wineries in California, in particular drought conditions and their affect on wine style, before mentioning Red Blotch as the biggest problem for growers in the region at the moment.

Having told db that he has already pulled out 22 acres (9 hectares) of Cakebread vineyards due to the virus, he said there are “a lot of vineyards being ripped up now and being re-planted with virus free vines”.

And, suggesting that there was a lot more replanting still to take place, he said, “We think Red Blotch is the next big issue for California, and the impact is like phylloxera in the late 80s and early 90s – Red Blotch is the one that’s coming up.”

During the 1980s a new type of phylloxera started to attack vines in California that were planted on the ARx1 rootstock, which was previously believed to be immune to the parasite that had devastated European vineyards in the late nineteenth century.

So, by the mid 90s, in Napa and northern California, as many as half the total area of vines had been destroyed.

Red Blotch was discovered in the US in 2008 by researchers from the University of California, Davis, who found the virus in Cabernet Sauvignon vines at the Davis Oakville Station Experimental Vineyard in the Napa Valley.

Cakebread said that currently there is no treatment for the virus, which, as its name suggests, causes the vine’s leaves to develop red blotches.