Local mandolin picker and strummer Aaron Firetag gets around, and his skills don’t always apply to traditional folk or modern-day jamgrass. For the second year in a row, Firetag presents five of his bands as a musical birthday bash. Firetag formed the acoustic duo FolkGrass seven years ago with singer/guitarist/harmonica player Bryan Watson. He gradually branched out and joined groove/roots combo Quasiphonics, the pop/folk quintet Lost Highway, and the experimental punk-metal band Skwirl Grinda. Lately, he’s performed with local songwriter Igoe at a variety of shows. All five acts are on the bill for Firetag’s Birthday Bash. It’s a free event. The music starts at 9 p.m.