Acclaimed troubadour Sierra Ferrell is not the only young singer-songwriter to react enthusiastically at the mere mention of Bob Dylan and the underappreciated American folk music master Elizabeth “Libba” Cotten. But it is her level of enthusiasm that distinguishes Ferrell, whose earthy yet slightly exotic country, bluegrass, swing, folk and tango songs sound all the more vital for embracing an era that predates rock ‘n’ roll. The West Virginia native reacted excitedly when told by her interviewer that gospel-music legend Mavis Staples and Elvis Costello are confirmed to perform in May at the …
