The Dry Branch Fire Squad are part curators, part mad scientists, breathing life and blood back into that great melancholy tradition of mountain and old-time music. In-your-face traditionalism isn’t the key to fame or wealth in this dimension or any other, so the band has thrived mostly on the festival circuit, where bandleader Ron Thomason’s folksy monologues create the atmosphere of an old-fashioned radio show. Their recorded output hasn’t always matched the fire of the band’s much-beloved live shows, which is where this Rounder best-of comes in handy, cherry-picking 20 years of plaintive, rough-edged folk music for its most indelible moments. (Their first Rounder anthology, 1988’s Tried and True, covered the first 10 years of Ron Thomason’s career.) Highlights include the excellent, hard-driving “Rollin’ on Rubber Wheels,” a little-known Carter Stanley composition, Thomason’s duet with the great Hazel Dickens on “Hide You in the Blood,” and a lovely, heartfelt version of the Emmylou/Earl Thomas Conley ballad “Happy Endings” (showing, as Thomason says, that the collaboration of country and bluegrass can “go both ways”). The mournful harmonies on the Carter Family’s “A Distant Land To Roam” raise the hairs on the back of your neck, just as they ought to, and the band’s version of Utah Phillips’ “Orphan Train” achieves a poignance seldom heard in this often stoic musical form.