At its heart, bluegrass music is about what happens when you commit to the moment. This spirit of spontaneity is ever-present on the self-ti- tled record from Mighty Poplar, a new all-star roots project featuring Andrew Marlin of Watchhouse, Noam Pikelny and Chris Eldridge of Punch Brothers, bassist Greg Garrison (Leftover Salmon) and fiddler Alex Hargreaves (Billy Strings). Across 10 songs that include bluegrass and folk classics and deep cuts from the Carter Family to Leonard Cohen, the fivesome captures the fierce and playful energy of a late night jam between old friends. Regarded as some of the finest players of their generation, the playing is never showy and always in service of the song. Careful reworkings of Dylan’s “North Country Blues” and Martha Scanlan’s “Up on the Divide” sit comfortably next to a rip-roar- ing pass through the fiddle tune “Grey Eagle.” Mighty Poplar’s mem- bers, known for pushing American acoustic music in progressive direc- tions, wanted to return to their roots to make a bonafide bluegrass record to celebrate the music they hold so dear. Recorded with the band sitting knee-to-knee in a woodsy studio outside Nashville, the band eschewed the smooth production style of contemporary bluegrass in favor of the methods and spirit of their most cherished classic bluegrass recordings. As a whole, the songs are as immediate and emotionally impactful as the playing is tasteful. This is bluegrass music at its zenith: thoughtfully crafted by players with off-the-charts chemistry. On Mighty Poplar, they've captured lightning in a bottle.