American Wild Ale is a singular style that may encompass such beers as American-Style Sour Ale, American-Style Brett Ale and Wood- and Barrel-Aged Sour Beer. “Wild” generally refers to the presence of some level of sour, tart, funky or barnyard-like aromas and flavors from the purposeful introduction of a wild Brettanomyces yeast strain, or friendly bacteria such as Lactobacillus. Brewers make them from existing beer styles, creating a special “wild” version, or they may formulate a stand-alone wild beer. Sour beers are an acquired taste for many, yet they are gaining in popularity in the United States. The base beer styles from which these wild ales emerge include everything from fruit beers and Belgian styles to brown ales, and they cover the beer color spectrum from light to dark. Many Wild Ale offerings are special-release beers, not available year-round.