include California common beer or "steam beer", Kentucky Common Beer, amber ale, blonde ale and cream ale. Contemporary craft styles Numerous beer styles have emerged in the United States since the beginnings of the craft beer movement in the 1970s, ranging from variations on traditional European styles to much more experimental ales and lagers. American craft beers frequently employ newer American hop varietals such as Cascade, Citra, Simcoe, Willamette, or Warrior. These hops, developed by private growers and universities since the 1970s, contribute to the distinctiveness of many American craft beers but are especially important to the flavor of American Pale Ale (APA) and American India Pale Ale. These beers can deviate considerably from the traditional English styles they were adapted from and are often robustly bitter, resinous, or fruity. The American "double" or "imperial" IPA, a popular style credited to Russian River Brewing Company brewmaster Vinny Cilurzo, can be extremely hoppy and strong, ranging from 7–14% ABV with bitterness ratings routinely topping 90 IBUs. Similarly, American stout beer, inspired by Russian Imperial Stout, may be hoppy and high in ABV, such as Deschutes Abyss or Goose Island's Bourbon County Stout, which is fermented to 15% ABV and conditioned in bourbon barrels. An emerging style associated with the Pacific Northwest is Cascadian Dark Ale, alternatively known as Black IPA, a heavily hopped beer with dark, roasted malts. Other adapted styles with distinct American variations include Irish red ale, brown ale, Scotch ale, wheat beer, rye beer and barleywine. Some breweries, such as Off Color Brewing in Chicago, focus on resurrecting styles that have been essentially extinct since the advent of Reinheitsgebot in Germany. Belgian beer styles have also been adapted by American breweries, including saison, dubbel, tripel, and Belgian strong ale. The lighter of these (saison, golden strong ale and tripel) beers have soft malt flavors and mild to strong "spicy" characteristics that come from yeast or the addition of spices. The darker of these beers (dubbel and dark strong ale) may have flavors of dried fruit that derives from the malts, yeast and sugar used to make them. All of these beers are high in carbonation and low in hop character. Witbier, a style nearly extinct until reintroduced by Belgian brewer Pierre Celis in the 1960s, is one of the top-selling craft beer styles in the United States. Brewery Ommegang, Jolly Pumpkin, and The Bruery are other examples of