Over the weekend Widespread Panic celebrated the release of its latest studio effort, Earth to America, with three high-profile shows at Morrison, CO’s Red Rocks Amphitheatre. In addition to longtime Panic producer John Keane, who is on the road with the sextet for the summer, the group also invited out additional guests each night. Friday, Luther and Cody Dickinson, who were in Colorado for a performance with John Hiatt, joined the group during its second set. First, Cody Dickinson emerged on keyboards for ‘Stop Breakin’ Down Blues.’ Soon after, his brother Luther joined him on guitar for ‘Junior.’ Finally, Luther Dickinson helped the group through ‘I Walk On Guilded Splinters.’ As he often does, a day later crew member Steve Lopez performed with Widespread Panic on a cover of War’s ‘Slippin’ Into Darkness.’ Similarly, longtime guitar technician Sam Holt enhanced a segue between ‘Impossible,’ ‘Machine’ and ‘Barstools and Dreamers’ on the final night of the group’s three-night stand. Widespread Panic will perform at San Diego’s Bayside at Embarcadero Marina Park South on Wednesday.