The customary way to get rid of vineyard clippings and old vines is to burn them in the wet season, but the times are changing.

A draft county climate action plan proposes alternatives to the traditional open burning of vineyards, while environmentalists are pushing to end burning altogether. Both efforts are rooted in ultimately reducing the county’s greenhouse gas emissions.

In response, the wine industry is promoting “low-smoke” techniques that would allow continued burning in the vineyards where the debris is gathered. To reduce smoke, clippings and vines are dried under a tarp for up to six months, then ignited starting at the top of the pile, not the bottom. The reduction in smoke can be dramatic.

“The air quality is not so much diminished by agricultural burning as people think,” said Steve Moulds, owner of Moulds Family Vineyards and a member of the Napa Valley Grapegrowers. “The only problem is that it all happens at the same time of year and it looks pretty bad. For the few days that we have it, it does make an impact on air quality.”

To combat the prevalence of smoky burns, the Grapegrowers in 2015 launched the Vineyard Burning Task Force and a campaign to educate members on the need for low-smoke vineyard burning.

Task force member Roberto Juarez, vineyard manager at Moulds Family Vineyards, leads courses for other vineyard managers and farmworkers as part of the group’s outreach. The courses, which Juarez teaches in Spanish and in English, explain best practices for burning vineyard debris with as little smoke as possible.

“We have children and … it’s good for them if we start doing the best as we can, the best (clean burn) as possible,” Juarez said of the task force. Not losing the opportunity to burn, Juarez said, is also a key concern.

The task force was originally planned as a three-year effort, Moulds said. He now wants to extend the program to a five-year plan. “But I don’t know that we’re going to have that much time, given the climate action plan is looking at making some changes,” he said.

That climate action plan is Napa County’s effort to curb greenhouse gas emissions locally over a span of several decades. Among the emissions targeted for reduction are those linked to the open burning of agricultural waste.

The current draft of the plan includes a measure to end open burning and to encourage alternatives, like converting agricultural waste into biochar or burning it in a waste-to-energy plant, which the county might help fund.

Though the plan has been a cause for concern among the Grapegrowers, county Planning Director David Morrison stressed, “We’re not calling for the stopping of ag burning. We’re calling for a different approach to ag burning, number one. And number two; it’s a multi-year, decades-long plan.”

“We’re very aware of the concerns expressed by the Grapegrowers and are taking those into consideration as we prepare the final draft of the climate action plan,” Morrison said. That draft might be sent to the Board of Supervisors for consideration between June and August of this year, he said.

“What we would want to do would be to work cooperatively with the Grapegrowers to find an approach that allows them to continue to burn, but in a way that helps the county as a whole meet its greenhouse gas emission goals,” Morrison said.

Those in support of a long-term plan that eliminates open burning in the county point to the pressing need to cut climate-changing greenhouse gas emissions as soon as possible.

“Our problem right now, in Napa and all over the world, is to find ways to immediately begin to push back irreversible climate tipping points, and the way we do that is by focusing on short-lived climate pollutants such as black carbon and methane,” said Jim Wilson, who sits on the board of directors of Napa Vision 2050, a coalition of local groups focused on environmental protection.

Wilson said that rather than burning agricultural waste biomass, “we should be generating electricity through a plant,” like the one described in the current draft of the climate action plan.

“We applaud the focus that Napa Valley Grapegrowers have on greatly reducing black carbon emissions,” Wilson said. Ultimately though, the goal should be to eliminate burning altogether, he said.

“They’re definitely going in the right direction,” Wilson said. “Can we be going further? What we’re saying is, ‘let’s figure out a way to not burn at all.”

Moulds argued that alternatives to burning would be costly, and would not be suitable for dealing with vineyards removed because of disease and pests. “If we have to start hauling away diseased vines, it’s still going to exist somewhere,” he said. “So if we can burn them and continue to burn them cleanly, we hopefully will not lose that right.”

While the final draft of the climate action plan is still pending, the authority to regulate Napa’s open burning in the more immediate sense lies with the Bay Area Air Quality Management District (BAAQMD).

County Supervisor Brad Wagenknecht, who represents Napa on the air district board of directors, said the likelihood that the district might issue an end to Napa’s agricultural burning soon is low. But he pointed to the persistence of smoky burns in the county as being detrimental to the practice being allowed to continue.

“There are folks that are burning illegally and do it poorly,” Wagenknecht said.

Moulds echoed that sentiment. “If there’s a continued flagrant disregard for best practices, and keeping smoke at an absolute minimum, then it’s just like rubbing salt in a wound.”

When he sees smoky burns taking place throughout the valley, Moulds now stops at the sites to inform those responsible about the need for best practices when burning.

Describing a recent visit to a smoky burn he spotted near his ranch on Dry Creek Road, west of the city of Napa, Moulds said he arrived at the site and approached the workers overseeing the burn.

“I showed them a brochure,” he said, referencing a six-step guide to best practices the task force provides in Spanish and in English. “I explained why it’s really important that we do a smokeless burn, because we’re going to lose the right to burn the things that we absolutely need to burn.”

Moulds asked the workers to convey those concerns to their manager. “And (the manager) called me back about an hour later,” Moulds said, “… and he said, ‘Thank you. I didn’t know. We really want to do our best. We certainly don’t want to lose the right to burn, so we’re on board.’”

The BAAQMD permissive burn period ends this month, and fewer burns will take place until the burning season begins again in October.

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Wine Reporter / Copy Editor

Henry Lutz covers the local wine industry. He has been a reporter and copy editor for the Register since 2016.