Five to watch for at Old Pool Farm

This year marks the Philadelphia Folk Festival's 50th birthday. But it's been a few years since the festival organizers' realized that the august institution, which takes place every August at the Old Pool Farm in Upper Salford Township near Schwenksville, needed to attract a younger audience to ensure that it has a future to compare with its storied past.

In recent years, festival bookers Rich Hardon and Jesse Lundy have brought in marquee names like the Decemberists and Jeff Tweedy of Wilco to give the fest a contemporary buzz. "We're trying to get the young crowd," says festival host Gene Shay, "and also retain the legacy audience."

This year, there's no single act that's as big a draw as those two. But the fest is bringing in a number of sharp, talented artists on their way up, from localites Hoots & Hellmouth and Birdie Busch on Friday to Canadian femme duo Dala on Sunday. Here are a few acts to watch for, beginning with the Thursday night Camper Concert hosted by David Dye, of WXPN's World Cafe:

Amanda Shires. Texas fiddler Amanda Shires grew up in Lubbock, home to Buddy Holly and the Flatlanders. The sweet-voiced singer, who plays ukulele and has toured with Jason Isbell and Justin Townes Earle, adds her own page to that high-plains story with her promising debut Carrying Lightning. The album has at least one stop-you-in-your-tracks stunner with the Dolly Parton-worthy "When You Need a Train It Never Comes." Thursday night at the Camper Concert at 7:30.

Justin Townes Earle. The son of Steve Earle was middle-named after Townes Van Zandt, so it almost seems destiny that he'd grow up to be a folk-country traveling troubadour with hard-livin' stories to tell. And, indeed, that is the way it's worked out. It couldn't have been predicted, though, that Earle, 29, would progress so rapidly from the release of his debut album, 2007's Yuma, to last year's powerful and poignant Harlem River Blues, which marks him as one of the best songwriters of his generation. Friday on the main stage at 7:30.

Caitlin Rose. On her full-length debut Own Side Now, the 24-year-old daughter of Nashville songwriter Liz Rose (who cowrote Taylor Swift's "You Belong With Me") establishes herself as an alt-country force with a keen eye for detail - see the superb "Shanghai Cigarettes" - with influences ranging from Patsy Cline to Fleetwood Mac. Sunday on the craft stage at noon.

David Wax Museum. With an ethnomusicological bent and a donkey jawbone for a percussion instrument, the David Wax Museum - led by Harvard grad and Mexican folklorist David Wax - is perfectly suited for folk-fest crowds. The band's album Everything Is Saved was produced by Josh Ritter knob-twiddler Sam Kassirer. And what's made them such a big hit at the Newport Folk Festival the last two years is the abundant energy Wax and his jawbone-rattling partners in folk bring to the stage. With Caitlin Rose Sunday on the craft stage at noon.

Jessica Lea Mayfield. Kent, Ohio, native Jessica Lea Mayfield won't yet be 22 when she makes her folk-fest debut, but the bleached-blond singer-songwriter already has a knack for despairing, lovelorn songs. They bring to mind Lucinda Williams and Nick Cave, as hearts are torn apart by forces beyond their control. Mayfield's second album, Tell Me, was produced by the Black Keys' Dan Auerbach, and it finds her dark vision maturing at an impressive pace. Sunday at 3:30 on the lobby stage.