The end of a music festival is always a bittersweet time. All the good times are coming to an end and you have to go back to your day job or whatever on Monday. What better way to close it out than with the sublime music of The Decemberists? It was the band’s first stop in Des Moines in 13 years, and they quickly made up for lost time with some older jams the Iowa crowd had been exploding with anticipation to hear.