Pace of vineyard development is accelerating

Linegar's office, which processes applications for all vineyard plantings, has been inundated with work, he said.

"It is hard to keep up with the volume we've received lately, and we're doing our best to turn them around as quickly as we can," Linegar said.

Grapes are the most valuable crop in Sonoma County, where growers sold $583 million of the fruit last year harvested from nearly 59,000 acres of vineyards.

Now, they are reinvesting some of that money back into their vineyards. Over the last two and half years, growers and wineries have filed applications to plant nearly 1,500 acres of new vineyards in Sonoma County and replant more than 2,300 acres of existing vineyards.

The pace of activity quickened last winter and this spring. So far, 75 applications for new or replanted vineyards have been filed with the Agricultural Commissioner's office this year, up from 44 filings during the same period last year, according to public records.

"During the height of the recession, when nobody could sell grapes, there were a lot of vineyards that were pulled out because they were at the end of their useful life and the market was weak," said Nick Frey, former president of the Sonoma County Winegrowers. "So those are getting replanted now."

"There are a few people that are planting new vineyards," Frey continued. "Probably Jackson Family Wines is one of the more aggressive."

More than a third of the new vineyard acreage proposed in Sonoma County since the start of 2012 has been sought by Jackson Family Wines, according to property records.

The company proposed a 107-acre vineyard on Browns Lane in Petaluma and another 40-acre vineyard on Ramal Road in Sonoma. Vineyard managers applied to plant two vineyards on land owned by the company, including a 224-acre vineyard on Browns Lane in Petaluma and an 89-acre vineyard on Bennett Valley Road outside Santa Rosa.

Jackson Family Wines spokesman Jason Hunke declined to be interviewed for this story.

So far this year, growers across the county have proposed planting 1,238 acres of grapes. More than 40 percent of the proposed acreage, or 503 acres, are for new vineyards, while 736 acres are existing vineyards that need replanting.

A cluster of new vineyards are planned for west Sonoma County, dotting the landscape around Highway 116 from Sebastopol to Forestville. The projects are fueled by demand for pinot noir and chardonnay, Frey said.

"Both of those grapes are the primary ones in the area, so I think the market is driving the development," he said.

New vineyards and replants are planned for the Sonoma Valley and Carneros regions. Meanwhile, the Dry Creek and Alexander Valley appellations will be active with vineyard replantings.

Sangiacomo Family Vineyards is replanting about 50 acres this year, mostly in the pinot noir and chardonnay varietals, said partner Steve Sangiacomo. The company typically replants 2 to 3 percent of its vineyards annually, but is doing more this year as more of the vines have reached the mature age of 30.

While the pace of applications has quickened, the planting itself has been constrained by limited supply of vines. It takes several years to grow the planting materials, which were in short supply a year ago and still haven't fully caught up with demand.

Complicating matters is a virus known as "red blotch," which growers believe delays ripening in grapes. The virus has been found in some of the rootstock and vineyards.

"The new discovery of the red blotch virus made the supply of planting materials even shorter, because you start eliminating those sources of grapes that everyone thought were clean materials," said Duff Bevill, founder of Bevill Vineyard Management, which is currently replanting vineyards and has filed applications for new vineyards in Sonoma County.

At NovaVine Grapevine Nursery in Santa Rosa, a small percentage of planting materials produced there or by its vendors have tested positive for red blotch virus, said Jay Jensen, CEO.

"People have canceled their orders, or else what they're doing is changing it to another clone that doesn't have red blotch," Jensen said.

Even so, the nursery has had another strong year.

"Things still feel pretty good," Jensen said. "If it wasn't for red blotch it would be fantastic."

Silverado Premium Properties had to switch out about a quarter of the stock it planned to plant statewide because of red blotch, said Pete Opatz, vice president and senior viticulturist at Silverado Premium Properties.

"We've been able to find enough clean plant materials to get us through '13, but it was an exercise, that's for sure," Opatz said. "A lot of our own staff have been going out and testing to verify that we were being shipped clean material by the nurseries."

As the applications for new vineyards arrive at Linegar's office, staff evaluate whether the projects need additional studies on erosion control or tree removal. The vast majority of projects since 2000 have been approved after providing the required information - only six applications were withdrawn out of about 1,800, according to the Agricultural Commissioner's office.

Impacts to wildlife, water and other environmental issues are not currently part of the review process, Linegar said.

"There are people that would like to see us incorporate more into the process, but at this point the ordinance (governing vineyard planting) was designed to address erosion and sedimentation, and that's pretty much what it's limited to," Linegar said.

As growers look for clean roostock to plant, researchers at the University of California at Davis, Cornell University and elsewhere are working to determine the impact of the red blotch disease and how it is spread, said Rhonda Smith, viticulture farm advisor with the UC Cooperative Extension. The virus is known to cause red splotches on the leaves of red varietals, but beyond that, little is known, she said.

"In terms of what it does to white grape vines, that's my task in Sonoma County," Smith said.

While grape growers have linked the virus to stunted grape maturation, that has not yet been scientifically proven, Smith said.

"No one knows what the impact is right now," Bevill said. "The fear is that it could spread, but we don't know how."

News Researcher Janet Balicki contributed to this report.