“Syrah tends to lose its character at higher ripeness levels,” he said. “The thing that makes syrah beguiling, beautiful and feral is all lost, and you end up with a much more generic, fruity experience.”

Pax Mahle can attest to that personally. Back in 2000 he founded Pax Wine Cellars, making rich, powerful single-vineyard syrahs that were acclaimed by critics like Robert M. Parker Jr. and Wine Spectator. Some of these wines reached alcohol levels above 16 percent. But after a dispute with a financial backer, Mr. Mahle left Pax. He and his wife, Pamela, now make wines of a completely different style under the Wind Gap label, right here in Forestville.

“The Pax wines were good of their kind,” he said. “But I found on a Tuesday or Wednesday night they were the wines I least wanted to drink.”

So he recalibrated his approach, and now aims for lower alcohol, subtler, more savory wines.

“I want the wines to show more earth than fruit, more savor and spice than sweetness,” he said. “I want them above all to be bright and fresh.”

His 2006 Sonoma Coast syrah is full of the herbal, meaty, bacon and olive flavors craved by lovers of northern Rhone wines. It weighs in at 13.1 percent alcohol, but even his biggest wine, at 14.9 percent, from the Castelli-Knight vineyard in the Russian River Valley, is discernibly Rhonish.

Contributing to the confusion is the fact that a good deal of California syrah is simply planted in inappropriate places.

“If you want it to actually have character, it needs to be grown in a very cool climate,” said Mr. Grahm of Bonny Doon Vineyards, and most top syrah producers would agree.

The Peay brothers, Nick and Andy, along with Nick’s wife, Vanessa Wong, grow syrah on their vineyard near Annapolis, in the extreme northwestern corner of Sonoma County just four miles from the Pacific Ocean. There, the fruit struggles to ripen each year, but retains a freshness that comes from sufficient acidity in the grapes.

“Syrahs from warm areas lack the syrah signature of pepper, olive, meatiness, iron and mineral,” Nick Peay said. “From warm areas they just have this monochromatic blueberry and oak quality.”

His brother chimed in: “There is no better wine for lamb, game and meats, but people are making wines with too much alcohol, too much fruit, no elegance and too much oak.”

The Peay syrahs are elegant and polished, not quite as savory as the Wind Gap or Arnot-Roberts wines, perhaps, yet still dripping with the pepper, olive, meat and animal character of syrah.

Cool climates, at least in Northern California, are not without risk. Arnot-Roberts made a delectable wine from the grapes from Clary Ranch on the Sonoma Coast in 2006. In 2009, they didn’t ripen enough to make a single-vineyard wine.

As with any grape there is no single correct way of making a syrah. It mostly comes down to the personal preference of the growers and winemakers.

“The single most important thing is making a good decision about when to pick the grapes,” said Mr. Edmunds of Edmunds St. John, who makes gentle, graceful syrahs with grapes purchased from a variety of sites in California. His preference is for freshness, so he tends to favor those picked on the early side. Other producers, including many in Paso Robles and Santa Barbara County, prefer riper grapes and bigger wines.

“Just because you can get it riper doesn’t mean you should get it riper,” said Mr. Lindquist of Qupé, who has never strayed from his original ideal of balanced, Rhone-influenced wines.

While the finest syrah producers still manage to sell their wines, it is not without a struggle. Wells Guthrie of Copain Wine Cellars makes excellent single-vineyard syrahs with enthralling mineral, saline, briny flavors. His loyal customers buy direct from the winery. Nonetheless, from the 3,000 cases of single-vineyard syrah that he made in 2006 he reduced his production to 1,200 cases in 2009.

“Without the good portion that we sell direct, I don’t know how you would sell any syrah,” he said.

Still, producers are keeping their hopes up. Mr. Jordan of Failla points out how young California’s syrah vineyards are, and how much the grapes will improve as the vines age.

“People are already making dynamic wines, and are increasingly conscious of where things should be,” he said.

Mr. Grahm, Mr. Edmunds and Mr. Lindquist, who’ve seen consumer interest in California syrah rise from nowhere only to crash and burn, likewise continue to focus on the potential.

“It’s a great grape, obviously,” Mr. Lindquist said. “And great grapes always rise to the top.”