A new beer style is emerging, one with the citrusy hop bouquet of an India pale ale but the color of India ink.

It's so new that beer enthusiasts are still groping for a name.

"Black IPA" would be a contradiction in terms: How can you be both black and pale? "India black ale" would be more accurate; however, at least one brewery has had that term struck down by federal labeling authorities for not being an accepted style. But "Cascadian dark ale," or CDA, is gaining currency, especially in the Pacific Northwest, where the style has proved popular.

The name is faintly seditious, derived from the Republic of Cascadia, a fantasy country that would be carved out of Oregon, Washington and the province of British Columbia through seccession from the United States and Canada. (Hopworks Urban Brewery in Portland, Ore., has gotten into the spirit by releasing Secession Black India Pale Ale.)

CDAs defy stylistic conventions. "I'm always surprised by how different this tastes from how it looks," Nathan Arnone of Southern Tier Brewing in Lakewood, N.Y., said about his brewery's Iniquity Imperial Black Ale.

CDAs have a unique flavor profile that you can't duplicate merely by mixing a stout and an IPA. Brewers prefer such hop varieties as Cascade, Centennial, Simcoe and Amarillo, aromatic American strains with flavors often likened to grapefruit, lemon or orange. Hopping rates are often greater than in normal IPAs, and dry-hopping - adding hops during the fermentation or later - is a common practice.

Brewers, however, usually avoid the heavily roasted grains that give stouts their coffeelike and burned-toast flavors. Instead, they rely heavily on de-bitterized malts such as Carafa, in which the husk has been removed from the barley kernels to provide a smoother, less acrid flavor.

"The black malts and the hops don't always play well together, like two kids in a sandbox who don't get along," says Larry Sidor, brew master for Deschutes Brewery in Bend, Ore. Sidor said he did 22 test brews before he found a harmonious combination that the brewery released as Hop in the Dark.

Deschutes doesn't send its beers any farther east than Minneapolis, but several other black IPAs are available locally. Sublimely Self-Righteous from Stone Brewing in Escondido, Calif., strikes a beautiful balance between the bittersweet chocolate flavors of the malt and the resiny hops. With an alcohol content of almost 9 percent by volume, it might properly be termed an imperial CDA. Equally potent is Southern Tier's Iniquity, but that one lies more on the stout side of the equation, with a rich fudge-cake flavor emerging ahead of the prickly hops. On the other hand, Back in Black from the 21st Amendment Brewery in San Francisco has an aggressive grapefruit tang that melds well with the acidity imparted by the black malts. It's unique among black IPAs in that it comes in 12-ounce cans; it is contract-brewed and packaged at Cold Spring Brewing in Cold Spring, Minn.

Four breweries in Nelson County, Va., have collaborated on a black IPA for the annual Brew Ridge Music Festival scheduled for Aug. 21 at Devils Backbone Brewing in Roseland. A single 25-barrel batch (50 kegs' worth) was brewed at Starr Hill Brewing in Crozet in mid-July: "It was an opportunity to brew something we've never done before," brewer Jason Oliver said. Look for it to turn up at the participating breweries (which also include Blue Mountain Brewery in Afton and South Street Brewery in Charlottesville) starting early this month.

An interesting characteristic of black IPAs is that the dark malts bring out hop flavors that you don't encounter in a paler ale. Some tasters pick up mint and rosemary. I've occasionally noticed a hint of ginger in dark, hoppy beers, but it might be my brain trying to force an unfamiliar combination of tastes - sweet malts and spicy hops - into a familiar slot.

Still another flavor, licorice, pokes through in Bashah, a collaboration between Stone Brewing and Scotland's BrewDog that's fermented with a Belgian yeast strain.

As with most emerging styles, there is a debate over who got there first. "The question is a sticky one," allows Abram Goldman-Armstrong, a beer writer from Portland who organized a Cascadian dark ale symposium in January to help draw up parameters for the style. Goldman-Armstrong asserts that the "first true CDA" he ever sampled was Skull Splitter from Rogue Ales in Newport, Ore., a special release for the 2003 Oregon Brewers Festival. He credits a home-brewing friend, Bill Wood of Seattle, with coining the term Cascadian dark ale.

Adam Avery, founder of Avery Brewing Co. in Boulder, Colo., insists that his New World Porter, introduced in 1997, would fit neatly into the style. Avery's recent anniversary brew, dubbed Seventeen, also bears a kinship to black IPAs, although it contains German rather than American hops and is fermented with a lager yeast.

In the July-August issue of Zymurgy, a magazine for home-brewers, contributor Ted Hausotter pegs Vermont as ground zero for the style. In 1990, he recalls, the late Greg Noonan, founder of Burlington's Vermont Pub and Brewery, roasted his own malts to craft a dark IPA called Blackwatch.

Why not Vermont? The state existed as an independent republic from 1777 to 1791 and has its own semi-serious secessionist movement called Second Vermont Republic.

It's an appropriate birthplace for a rebellious beer.

Kitsock can be reached at food@washpost.com.