This past weekend, Yonder Mountain String Band wrapped up a pair of shows in their native Colorado. The groups big, sold-out headlining performance at Red Rocks took place on Sunday, with Jon Fishman performing with the group, as billed. On the previous evening, however, at Boulders Fox Theatre, Fishman also joined in, as the band expanded to a quintet for most of the second set. Fishman-abetted highlights from Saturday included a set-closing sequence from Girlfriend Is Better into a jam that eventually yielded a drum and bass segment before segueing into 2 Hits & The Joint Turned Brown. On Sunday, Fishman emerged late in the first set For How ‘Bout You and then Kentucky Mandolin which carried into Steep Grade Sharp Curves and then reappeared for much of set two. The five musicians will go it all again on October 6 at the Congress Theater in Chicago.