Aaron Firetag has become Charleston’s most recognizable mandolinist, and it all has to do with his collaborative mentality. A skillful string player, Firetag stays busy playing mandolin in several projects, including the pop/folk quintet Lost Highway, the punk-metal band Skwirl Grinda, and the groove/roots combo Quasiphonics. He also plays as a duo called Folkgrass with singer/guitarist/harmonica player Bryan Watson. Through late July and August, Firetag will welcome a rotation of friends and musical guests to the Pour House deck stage. This week will feature members of Lost Highway. Folkgrass and guests will perform the following three weeks. “We may have a few guests come and sit in, depending on who’s free,” Firetag says. “I’m very excited for this opportunity extended to me by the Pour House.” Firetag plans on releasing a debut album with Skwirl Grinda in late fall, and he expects there to be a release show as well.