[HILLBILLY PUNK] It's not uncommon for a band to refine its sound with age, but when considering the discography of Bend's Larry and His Flask, you'd be forgiven for thinking two separate groups had stumbled on the same unlikely name. Founded in 2003 by brothers Jesse and Jamin Marshall, Larry and His Flask (known simply as "the Flask" to fans) spent their early years as strict purveyors of what guitarist Ian Cook describes as "really dirty punk rock." Until 2009, the Flask's reputation was built primarily on its talent for causing damage to grange halls, basements and keg parties in the woods.

"Jesse was always trying to smash something," Jamin says of his brother's early antics. "One time he fell over and bashed his skull."

In 2003, it would have strained credulity to suggest this band would not only be around eight years later, but would have ditched the political screeds for mandolin breakdowns and exchanged the hand-drawn fliers for write-ups in The New York Times.

"We never even thought, 'We want to be a punk rock band,'" says Jamin, who, like the rest of his bandmates, dresses somewhere between a punk and a spaghetti-western villain. "It was just what we could do. It just came out of us. And now that we put [this new incarnation of the group] together, it's the same way."

The 2008 departure of the band's original drummer, combined with the aforementioned stylistic wanderlust, made Larry and His Flask turn almost by accident to experiments in folk pop. After a meandering transition period, the Flask settled on its current, six-member lineup, effectively dressing the group's punk-rock past in the guise of an Appalachian jug band.

"For the first year of [the current form] of this band," Cook says, "we were constantly on street corners and outside as much as we could manage….We got a reaction from people from all walks of life, not just punk kids in basements."

The rowdy momentum that had characterized the band's formative years continued to turn heads. The Flask soon found itself forgoing busking in favor of tours with the Dropkick Murphys and five-show-a-day marathons on the 2010 Warped Tour.

Though the recording of the group's 2009 self-titled EP was hampered by guitarist Dallin Bulkley's temporary confinement in Virginia (Cook: "Not a violent crime, just a stupid circumstance"), Larry and His Flask were able to do justice to their reinvented sound with this year's All That We Know LP. Arriving with the intensity of a big-tent revival show, All That We Know reveals equal traces of the Avett Brothers and Virus Nine. Bluegrass-worthy banjo lines battle with metal-guitar riffs, all to the backbeat of Jamin Marshall's oom-pah-on-meth drumming. Lyrically, the album reflects some of the band's earlier political convictions, though strewn more generously with introspection.

"Earlier, I would write about politics and how much I hated religion, and now we don't really delve into that so much," Jamin says. "And if we do, it's much more cryptic than it used to be."

He considers for a moment, then adds, "Which is maturity, I guess, and that just comes from growing up and living."

SEE IT: Larry and His Flask play Doug Fir Lounge on Tuesday, Nov. 22, with Sassparilla and Third Seven. 9 pm. $5. 21+.