The 50th Annual Telluride Bluegrass Festival starts Thursday. Every June, thousands of "festivarians," as they're known, descend on the small mountain town for 4 days of music. This year's headliners include Robert Plant and Alison Krauss, Nickel Creek, Emmylou Harris, Béla Fleck and the Flecktones, and performing a 49th time, mandolinist Sam Bush. Ryan Warner spoke with Bush in 2014 along with then-Colorado Music Hall of Fame director G. Brown, author of "Telluride Bluegrass Festival: The First 40 Years."