A contentious Napa County measure that would have limited vineyard expansion into woodland areas is on track to fail by less than 2 percentage points, with 95 percent of the vote counted.

Supporters of Measure C conceded defeat but vowed to continue advocating for additional protections on trees and watersheds in the heart of the prestigious wine region.

Opponents, centered in the valley’s powerful wine industry, expressed willingness Monday to work with environmentalists to build consensus around land use regulations.

Any new regulations should be drafted by the county Board of Supervisors and subjected to the county review process, said Ryan Klobas, policy director of the Napa County Farm Bureau and an opponent of Measure C.

“We believe a science-based, data-driven process should guide this effort,” Klobas said.

Supporters of Measure C said they would continue to educate the public about the link between soil erosion and tree removal.

A future initiative is not out of the question, said Jim Wilson, co-chair of the Yes on C campaign.

“We will begin in earnest to see what our next steps are,” Wilson said.

Wilson attributes the measure’s failure, in part, to a lack of funding. The No on C campaign raised $645,858 as of May 28, more than three times the $211,504 raised by the Yes on C campaign, according to Napa County Election Division reports obtained by the Napa Valley Register.

Measure C would have allowed up to 795 acres of oak woodlands to be removed around hills and mountains in Napa County, starting the count from September 2017.

Trees destroyed by wildfires would not count against the total.

Landowners would need a special permit to cut down such trees beyond that level.

New vineyards would not qualify as a reason for the permits to be granted and would face stringent conditions.

The initiative also would establish new standards for buffers near streams, prohibiting the removal of trees within 25 to 150 feet from streams, depending on the wetland area.

Dead or dying trees would be provided an exception.

The measure was the result of three years of activism by local environmentalists concerned that vineyard expansion in the valley was promoting environmentally harmful clear-cutting of hillside forests.

Proponents contended that removing natural woodland could contribute to soil erosion, runoff and the alteration of hydraulic conditions in the area.

Opponents questioned the science behind Measure C and argued that it would promote the construction of large event centers and create more traffic congestion in the valley.

With 1,736 ballots still to be counted, Measure C trailed by 632 votes in the final, unofficial vote count issued by Napa County elections officials last week. Opponents outnumbered supporters 50.9 percent to 49.1 percent.

While proponents have not declared victory, Wilson said the gap is too big to overcome.

The final vote count will be certified on June 25.

You can reach Staff Writer Meghan Herbst at 707-521-5250 or meghan.herbst@pressdemocrat.com. On Twitter @Megeherbst.