The 2017 grape harvest began early Monday morning in American Canyon as a crew of about 40 workers quickly and efficiently picked rows of pinot noir grapes that will go into premium sparkling wine that has driven the North Coast economy for generations.

This year’s season resembles more of the historical norm as opposed to the early harvests in recent years and should wrap up by early November. Last year, harvest kicked off on July 28.The crop also is expected to generate at least an average yield, growers said. Last year, 503,965 tons of wine grapes were harvested in the North Coast, which was a 25 percent increase over the dismal 2015 season.

“It is rewarding so far because it has been a challenging growing season,” said Mumm Napa winemaker Ludovic Dervin, who will take the five acres of grapes that were harvested and turn it into a sparkling wine blend that should be available for purchase in about three years. Mumm’s wines sell from $25 to $125 a bottle.

The season started with heavy winter rains that were welcome after five years of drought and helped rejuvenate the vines’ root system. In the spring, bud break occurred without any extreme temperature changes that could have threatened the setting of the fruit.

The summer has not featured any prolonged heat spikes that could cause problems such as grapes shriveling on the vine. Growers, however, had to confront aggressive leaf growth on their canopies that triggered sporadic outbreaks of powdery mildew, a fungus that can lessen quality and quantity, if left unchecked.

“Mildew has been a challenge in some locations,” said Julie Nord, the vineyard manager overseeing the pick at the Green Island Vineyard, located where the Napa River meets San Pablo Bay.

In southern Sonoma County, Gloria Ferrer Caves & Vineyards received its first 2017 grapes on Monday, 18 tons of pinot noir from a grower on the Sonoma side of Los Carneros appellation. The vintner is still finishing bottling for upcoming releases of sparkling wines, and the new grapes weren't expected for another week, based on patterns for somewhat normal years, according to Steven Urberg, director of winemaking.

“However, the recent warm weather pushed some of the vineyard blocks carrying a lighter crop to ripen more quickly…,” Urberg said.

Picking starts on Gloria Ferrer's 335-acre estate Tuesday for select pinot noir that will be going into vintage and nonvintage brut rosé labels. The 2014 brut rosé retails for $50 a bottle.

The record rainfall in the North Coast over the winter gave the vines kickstart in growth come spring, but that slowed as roots in standing water or soaked soils struggled for oxygen, some not surviving, according to Mike Crumly, Gloria Ferrer vice president of production.

“This wet spring period caused the vines to stop growing while the root system regenerated,” Crumly said. “Short little shoots with stunted growth showed pale color, and everyone was very concerned.”

Gloria Ferrer forecasts it will receive just over 2,000 tons of grapes this season.

More of the 2017 harvest is expected to kick off later this week in Sonoma County, said Karissa Kruse, executive director of the Sonoma County Winegrowers trade group.

Business Journal Staff Reporter Jeff Quackenbush contributed to this report.