A “whiskey fungus” emanating from an assortment of Jack Daniel’s barrel houses is impacting residents in Tennessee’s Lincoln County. The fungus takes the form of a black mold blanketing the surrounding community from roads to homes and trees, according to Insider. Ethanol vapor emitted through the wooden barrels, inside the barrel houses, as the whiskey matures is thought to generate the fungus. Jack Daniel’s operates six barrel houses in the community with plans to build another 14.