After October’s devastating fires that ravaged the Northern California wine country, vintners, growers and most wine industry analysts are cautiously optimistic about the health of the 2017 vintage.

More than 20 wineries in Napa, Sonoma and Mendocino counties were impacted by the fires, everything from total destruction to minor cosmetic damage. No estimates on the number of vineyard acres that burned are currently available, but growers note that even in dry seasons, grapevines are as much as 50 percent water and acted as natural firebreaks to keep flames from spreading even further.

Some vineyards did burn, though, and others may have suffered heat damage; it’s too early to tell the extent and severity. Fire-damaged vines may not produce grapes for a year or two following the event but growers say even vines regrafted on undamaged rootstock will begin producing after that.

What nearly everyone in the wine business is fearful of, however, is smoke taint, the nasty flavor of smoke permeating grapes. Though 85 to 90 percent of the region’s grapes were already in fermentation when the fires struck, the remainder (mostly Cabernet Sauvignon, Merlot and Syrah) probably were affected to some degree by smoke, which could render them virtually unusable.

Whether grapes already in the winemaking process could be ruined by smoke taint is a question right now no one can answer. For an industry that contributes some $27 billion annually to the economies of Napa and Sonoma alone, there’s an awful lot riding on that answer.