Evolution Festival plans to be a big summer St. Louis event

The walls of Steve Schankman’s office in Clayton are decorated with memorabilia that tell the story of his decades booking concerts in the Midwest.There are ticket stubs, photos and a typewritten contract for a U2 performance in 1981 that reveals the fee the Irish upstarts commanded for an hourlong set at Washington University: $750.It’s a long and colorful history. But none of it ensures that his latest venture, this weekend’s Evolution Festival, will succeed.The Forest Park event..