The Sonoma County Board of Supervisors on Tuesday unanimously approved an emergency halt to new vineyards and orchards on forested slopes and hilltops.
The four-month freeze was prompted by a wave of new vineyard projects and a need to update 12-year-old farming regulations that don't deal with tree removal, officials said.
County Agricultural Commissioner Tony Linegar called that loophole a "deficiency" in the current rules.
"We've seen proposals that would remove a significant number of trees on steep slopes. I don't think it takes a rocket scientist to know that that is going to affect erosion," said Linegar, who assumed his post last month.
Grape growers and agriculture leaders provided guarded support for the move, with some saying they recognized the need to revise rules implemented in 2000. Those regulations allow development of hillside vineyards on slopes up to 50 percent, but contain no restrictions on tree removal.
"We understand that even the best rules over time need adjustment," said John Holdredge, board president of the Russian River Valley Winegrowers.
Still, many wine industry representatives voiced concern over the possibility of tighter regulations, saying they could impact the local economy and be a blow to smaller vineyard operations.
"I ask the process to be cognizant of that specific issue," said Pete Opatz, vice president of Napa-based Silverado Premium Properties, which manages more than 5,000 acres of grapes in the region and vineyards on the Central Coast.
Environmentalists and others who have questioned the reach of vineyards into previously untilled country welcomed the move.
"I've watched the cumulative impact of ridgelines that are stripped of trees and (replaced) by vineyards," said Bonnie Berkeley, who lives above Dry Creek Valley.
"This is the perfect time to pause and assess the (effect on) forested ridgetops and slopes."
Tuesday's decision, before a packed audience, sets up what is likely to be the continuation of a decades-long debate over the proper reach of the region's world-famous vineyards and how they are regulated.
The results could have far-reaching implications.
Two Annapolis-area proposals call for the conversion of over 1,900 acres of forest into land for wine grapes.
County officials have suggested those two projects — the 146-acre Artesa Vineyard proposal and the 1,769-acre Preservation Ranch project — would be subject to any updated regulations, as well as existing state and county rules governing timber-to-vineyard conversions.
In the short-term, the moratorium would affect seven pending vineyard projects covering 341 acres in western and northern Sonoma County. Artesa's proposal, which is further along than Preservation Ranch, is the largest in the affected group.
Others include the 122-acre project put forward on Skaggs Springs Road by Healdsburg vinters Ken and Diane Wilson of Wilson Winery.
Ken Wilson, contacted Monday by phone, said he was undecided on his stance on the moratorium. He said his property was mostly open land, with groves of oaks and madrones that would require removal.
"There's issues on both sides," Wilson said, adding "slopes have to be looked at carefully."
Also on the the list of pending projects is the 10.7-acre Pocket Canyon vineyard proposed by vintner Paul Hobbs.
Last year, Hobbs was is the news in connection with tree clearing trees on a trio of properties to make way for grapes. The work was permitted in two cases. In the third, the clearing of the Pocket Canyon property, Hobbs did not have the proper permits, a mistake he has acknowledged.