If a bottle of Oregon Pinot Noir has the word “Willamette” on its front label, would you assume that it comes from the Willamette Valley?

Probably, but if the bottle in question happened to be the 2017 Willametter Journal Pinot Noir, you would be wrong. Although the brand’s name implies a connection to the Willamette Valley, and although the front label includes the text “the Willamette region of Oregon’s coastal range,” the wine does not, in fact, qualify for the Willamette Valley appellation.

It’s one of the points in a larger controversy brewing over the Willametter Journal’s creator, Joe Wagner.

As the winemaker behind mega-hit Pinots like Meiomi and Belle Glos, Wagner is one of California’s most prominent winemakers. Now, the Oregon Winegrowers Association, along with a state lawmaker, alleges that labels on both the Willametter Journal and another of Wagner’s Oregon brands, Elouan, may have violated state and federal regulations by falsely advertising the grapes’ place of origin.

Although the controversy hinges on technical nuances of labeling laws, it raises much deeper concerns for wine producers and consumers. When it comes to wine, location — terroir — is everything.

Any successful wine region, whether Bordeaux or Napa Valley or Willamette Valley, depends economically on its name’s ability to command prestige. That’s why the federal government regulates the creation and use of American Viticultural Areas, to establish hard boundaries — and a common language — for wine regions.

“The idea of geographic standards of identity is a global phenomenon,” says Tom Danowski, president of the Oregon Winegrowers Association.

“Whether it’s Florida orange juice, Idaho potatoes, kobe beef from Japan, people around the world who are engaged in commerce have to protect the name of their geographies.”

“The industry here has spent 53 years creating an image for the Willamette Valley,” says David Adelsheim, who founded Adelsheim Vineyard in 1971. “Now our concern is the potential of people who may not have our best interests at heart to take advantage of the brand that is Willamette Valley Pinot.”

At the Oregon association’s urging, the Oregon Liquor Control Commission is investigating the complaints surrounding Elouan and Willametter Journal and has requested attention from the U.S. Alcohol and Tobacco Tax and Trade Bureau. Meanwhile, Oregon state representative David Gomberg, D-District 10-Central Coast, has asked the fraud and consumer protection division at the state attorney general’s office to conduct its own probe.

Wagner denies that he violated any statutes. “We have followed all TTB rules and regulations and have done nothing to warrant this type of press,” he wrote in an email.

At the heart of the Wagner kerfuffle is the use of fanciful names on the wine labels — words that sound like they refer to a geographic place but are not legally recognized terms for American Viticultural Areas.

The use of “Willamette” on the Willametter Journal label is fanciful; the question is whether that’s OK. And it’s not the only potential misnomer on the Willametter Journal bottle, according to the Oregon winegrowers group. The wine’s back label reads “Sourced from: Territory of Oregon.” But “Territory of Oregon” is not an American Viticultural Area — nor is Oregon, which was granted statehood in 1859, a territory.

In fact, “the wine appears to have no AVA,” says Danowski. That on its own would be a violation of federal code. “We would write a letter to the TTB about that even if that was an Oregon winery.”

What stood out to Gomberg, who discovered the Willametter Journal bottle while browsing in his local wine shop, was the phrase “Oregon’s coastal range.” He represents a coastal district. “There is no Pinot Noir grown on Oregon’s coast,” he says. “That’s kind of like saying ‘from the Sacramento region of San Francisco.’”

Wagner’s response: Everyone in Oregon, including the Oregon Wine Board, refers to the inland winegrowing regions as having “coastal influences.”

“We believe this validates our own statements within our romance language to describe how the character of the wine is developed with coastal and coastal range conditions,” he wrote.

The Elouan wine label presents a different, though similar, set of complications. The 2017 Elouan Pinot Noir carries the Oregon AVA, but the label makes mention of three of the state’s sub-AVAs: Rogue, Umpqua and Willamette — again, as fanciful names.

In order to use any of Oregon’s official vinticulture designations, at least 95 percent of a wine’s grapes have to come from the named region. It would be impossible for at least 95 percent of any wine to come from the Rogue, Umpqua and Willamette Valley AVAs, which do not overlap, simultaneously.

Finally, Oregon state law requires that any Oregon grapes processed outside of the state — trucked down to, say, California — carry only the Oregon AVA, and not a sub-AVA like Willamette Valley. The Elouan and Willametter Journal wines were finished in Rutherford, Calif., according to their back labels, which would further compound the violations surrounding their use of the words Willamette, Rogue and Umpqua.

“The Commission has reason to believe that some wines labeled with an Oregon AVA were not fully finished in Oregon,” wrote Oregon Liquor Control Commission chairman Paul Rosenbaum in a Sept. 6 letter to the Tax and Trade Bureau.

Wagner believes he’s done nothing wrong, since the wines do carry the simple, catch-all Oregon AVA, which permits a wine to be finished out of state. But he does not address the possibility that the use of fanciful names that happen also to be the official names of sub-AVAs might constitute its own violation.

Why should it matter where a wine is finished — that is, transformed from grapes into wine — if the label reflects truthfully where the wine is from? Simple: because Oregon imposes a unique set of rules on winemaking within its borders.

“Oregon has more restrictive labeling guidelines for wines made in Oregon than are in place in federal statutes,” says Danowski. Oregon requires that a wine be at least 95 percent from its listed AVA (federal law requires just 85 percent), and at least 90 percent its listed grape variety (federal law requires just 75 percent).

Many wine consumers may be surprised to learn how loosely enforced many wine labeling rules really are. The Tax and Trade Bureau employs fewer than 60 field investigators to cover 50 states, says Bernie Kipp, a retired district director of trade investigations at the bureau who currently advises on alcohol compliance for the law firm Stoel Rives.

All wineries are required to keep detailed documentation of their wine production — including records of their grape sources, varietal makeup, alcohol content and much more — but many will never have to show those records to anyone.

“Do the field investigators go out to wineries and do what they call product integrity investigations?” Kipp says. “Yeah. But it’s not real common, and it certainly is not every year.”

If found to be in violation of state and federal labeling laws, Wagner will likely simply be asked to correct future labels, Kipp speculates. It’s possible Wagner could face a fine from the Oregon Liquor Control Commission or a license suspension from the TTB.

The good news for Oregon wine: If you have to worry about protecting your name, it probably means you’re doing something right. Napa Valley, for instance, has spent decades trying to defend its name. The Napa Valley Vintners helped get a 2000 truth-in-labeling law passed in California that then became locked in a legal fight with Bronco Wine Co., which produced three wine brands — Napa Creek, Napa Ridge and Rutherford Vintners — not made with Napa Valley fruit. Bronco, better known as the maker of Two Buck Chuck, lost.

Similar battles surely lie ahead for Oregon wine as its star continues to rise. “We hope to get an early start on this, now that we’ve had a wake-up call,” Adelsheim says.

For the last year Adelsheim and other Willamette vintners, including Ken Wright, have been developing state legislative proposals to strengthen labeling requirements. For instance, any wine labeled as Willamette Valley Pinot Noir would have to be 100 percent Pinot Noir and 100 percent from the Willamette Valley if lawmakers agree.

Esther Mobley is The San Francisco Chronicle’s wine critic. Email: emobley@sfchronicle.com Twitter: @Esther_mobley Instagram: @esthermob