Sonoma County's wineries may seek passage of a state law requiring wines from its sub-appellations like Russian River Valley and Chalk Hill to also print "Sonoma County" on their wine labels to better promote the winemaking region.

The board of the Sonoma County Vintners voted this month to explore a "conjunctive labeling" law like the one adopted for Napa County wineries in 1987.

"We see significant potential benefit to Sonoma County wineries, grape growers and tourism," said Honore Comfort, executive director of the trade group, which represents about 160 of the county's wineries.

Appellations are federally recognized grape-growing regions that help consumers know where the grapes that went into wines were grown. Within the Sonoma County appellation, there are 12 sub-appellations designating various distinct growing regions, from the hardscrabble Rockpile northwest of Lake Sonoma to the wind-blown Carneros straddling the Sonoma-Napa border southeast of Sonoma.

Federal labeling regulations currently don't require a producer of Russian River Valley, Alexander Valley or Knights Valley wines to mention anything about Sonoma County on the labels. Some do, but most do not.

The idea of pursing a conjunctive labeling law like Napa's has been around for years, but it has gathered momentum recently as the Sonoma County Vintners, Sonoma County Winegrape Commission, and Sonoma County Tourism Bureau have worked more closely together.

Many in the grape-growing community support the concept, believing that the more the word "Sonoma" appears on labels, the greater the demand will be for their grapes.

"If we had Sonoma County on every label, we'd probably have 100 million faces on retail shelves and wine lists," said Nick Frey, president of the Sonoma County Winegrape Commission. "That presence would build our brand equity, much as Napa Valley has built their brand equity for the past 20 years."

In 1989, in an effort to better market their already esteemed wine region, Napa Valley wineries supported passage of a state law requiring "Napa Valley" to be printed on wine labels from the valley's sub-appellations.

As a result, today a Robert Mondavi cabernet sauvignon from the Oakville American Viticultural Area, located between Rutherford and St. Helena, can print Oakville on the front label, but it must also be followed by Napa Valley.

On such a label, the words "Napa Valley" must be no more than 1 millimeter smaller than "Oakville." The law is often cited as a significant step in Napa's evolution into the nation's most well-known wine region because it demonstrated Napa wineries' willingness to work together to promote themselves.

While Sonoma County has long been the second-best-known wine region in the nation behind Napa, it never sought to follow its rival's lead, preferring instead to emphasize the county's laid-back attitude, independent spirit and diverse growing regions.

But some believe the rise of separate grape-growing regions within the county runs the risk of diluting Sonoma's identity.

"Our market research suggests that when you get outside Sonoma County — you don't have to go very far — and people don't really understand AVAs and their proliferation," Frey said.

A new study further bolsters the idea that conjuctive labeling would have significant benefits for the county, Comfort said.

"From what we have seen so far, it looks like it is the right thing to do," Comfort said

She declined to share the research, saying she preferred to present it to winery officials privately over the next month to help gain consensus in favor of the move. The results of the research and input received from wineries will be jointly presented at the separate annual meetings of the vintners and growers on Jan. 20 and 21, she said.

"Between now and then, we've got a lot of work to do," she said.

While the research appears positive, the vintners group wants feedback from its members to help them decide whether to move forward, she said.

"We're very much in the listening mode," she said.

One of the likely concerns will be objections from the three viticultural areas that already have Sonoma in their names — Sonoma Coast, Sonoma Valley and Sonoma Mountain.

Tom Hinde, president of Cazadero-based Flowers Vineyards and Winery, said the winery only uses Sonoma Coast on its sought-after chardonnay and pinot noir. Adding Sonoma County to such a label seems unnecessary to him.

"I personally think it's duplicative," said Hinde, who sits on the vintners' board. "But I also feel that you need a conjuctive law that is free of exceptions."

Carving out exemptions for those three appellations would potentially be even more confusing, Hinde said.

"I expect there will be vibrant debate around it," he said.

Additional concerns likely will revolve around the cost of changing labels, the space needed on the already crowded labels for additional words, and the general opposition from those who "don't like to be told what to do," Frey said.

Implementing the concept would require changing state law. In addition to Napa, Paso Robles is the only other wine region to pass such a law. It did so in 2006, a move industry leaders there at the time called a "no-brainer."

Chris O'Neil, owner of Russian River Vineyards in Forestville, said he's happy to support Sonoma County, but doesn't want a new law to detract from the winery's strong identification with the Russian River Valley.

If it makes sense for Sonoma County, that's fine with him, but he'd hate to see Sonoma just trying to emulate its exclusive neighbor to the east.

"I question whether we as Sonoma County really want to follow Napa Valley's lead," he said.

You can reach Staff Writer Kevin McCallum at 521-5207 or kevin.mccallum@pressdemocrat.com.