Wilco's set at Mountain Jam 2016 was a marathon run, with Jeff Tweedy and company headlining the festival's second evening with a two-hour, 24-song performance. As the show wound its way toward a finish, the group was joined by Jason Isbell, who'd performed his own set earlier that Friday afternoon. Playing lead guitar alongside Nels Cline, Isbell helped Wilco kick "California Stars," one of the standout tracks from their Mermaid Avenue project with Billy Bragg, into fretwork-filled outer space.
Stretching the song's instrumental break by more than a minute, Isbell and Cline traded solos before stacking their riffs atop one another, turning the tune's final minutes into a swirl of hammer-ons and bends. Isbell stayed away from the microphone, too, leaving Tweedy to serve as the group's ringleader. The guys are all smiles in the video above, which feels like some sort of Americana summit, bringing together one of the genre's newest leaders with a group of pioneers.