A lawsuit seeks to overturn a state-approved timber harvest plan allowing Davis Estates to clear 10 acres of forest near Angwin for a vineyard.

The Center for Biological Diversity filed the suit in Napa County Superior Court. The defendant is the California Department of Forestry and Fire Protection, which oversees commercial timber harvests.

Davis Estates seeks to create a 13.6-acre vineyard using 10 acres that have such trees as Douglas firs and California foothill pines. The 38.7-acre site at 1875 Friesen Drive is in the mountains east of Calistoga.

“The clear-cutting and subsequent vineyard conversion of this forested area will destroy wildlife habitat, pose risks to surface water quality, produce greenhouse gas emissions and eliminate the site’s capacity to sequester carbon,” the lawsuit said.

In contrast, a 900-page draft environmental impact report issued by Cal Fire in 2015 concluded any potential environmental harm could be rendered “less than significant” with certain steps.

Napa County has seen an increasing number of vineyards proposed in the mountains as the Napa Valley floor has filled up. The dynamic has created community tensions that culminated in Measure C, the watershed and oak woodland protection measure that narrowly failed in the June 5 election after a bitter campaign.

Logging forests requires a Cal Fire permit. The Angwin area in recent years has had three timber harvest plan requests before Cal Fire to create vineyards, including the one by Davis Estates.

The Center for Biological Diversity has entered the fray with its legal challenge of Cal Fire’s Sept. 21 timber harvest plan approval for the Davis Estates Friesen vineyard. Davis Estates is pursing the vineyard under the name Frostfire Vineyards II, LLC.

“We are hoping to send a message to Cal Fire and Napa County,” Center for Biological Diversity staff attorney Aruna Prabhala said. “We are watching closely to what’s happening with these vineyard expansion projects in remote areas.”

The group previously sued Napa County to try to stop the Walt Ranch vineyard project in the mountains east of the city of Napa. That project involves removing oak woodlands not subject to timber harvest plans. Napa Superior Court ruled in favor of Napa County and the case is on appeal.

Mike Davis of Davis Estates couldn’t be reached this week to comment on the lawsuit. His Davis Estates winery is near Calistoga, a few miles from the proposed Friesen vineyard site.

However, Davis talked to the Napa Valley Register in 2015 about the proposed vineyard and how it fits in with the winery.

“When I put this whole project together, I built a financial model for a business plan to produce a lot of estate grapes,” he said then.

On Oct. 3, Davis Estates winery won Napa County Planning Commission approval to expand annual wine production from 30,000 gallons to 100,000 gallons.

The Cal Fire 2015 environmental report on the Friesen vineyards proposal drew 48 letters. The City of St. Helena wrote that the superior choice would be no project because the watershed drains into Bell Canyon Reservoir, a major city water source.

“Therefore, it is imperative that the watershed of this reservoir be managed to protect the health and life safety of the residents of the City of St. Helena,” a city letter stated.

But Stuart Smith of Smith-Madrone Vineyards and Winery wrote in defense of the Friesen project.

“This project represents one three thousandths of a percentage of Napa County and three one hundredths of one percent increase of vineyards in Napa County,” Smith wrote. “If there was ever a ‘de minimis’ project, this is it.”

A Center for Biological Diversity press release said about 500 acres in Napa County is converted to vineyards annually. Scientists with the National Marine Fisheries Service have warned that vineyard water use and soil erosion into creeks threaten endangered populations of steelhead trout, it said.

Planning, Building and Environmental Services Director David Morrison said the county has approved 12,032 acres of new vineyards since 1992, excluding replants. That’s an average of 445.6 acres annually. But the numbers have fallen in recent years.

“Fifty-five percent of all vineyard approvals since 1992 occurred prior to 2000,” Morrison wrote in an email. “In other words, we approved more vineyards in the first 10 years than in the past 18.”

Cal Fire did not return requests for a comment on the lawsuit as of Wednesday.