Dixie Chicks fiddler Martie Maguire will perform at the Telluride Bluegrass Festival this summer. She is reportedly at work on a bluegrass album. The Dixie Chicks won the festival's band competition in 1990, prior to lead vocalist Natalie Maines joining the band. Other artists appearing at the festival include the Zac Brown Band, the Sam Bush Band, Elvis Costello and Emmylou Harris, as well as Kasey Chambers, Jerry Douglas, Bela Fleck, the Greencards, Tim O'Brien, the Punch Brothers, Railroad Earth, Todd Snider, the SteelDrivers and the Yonder Mountain String Band. The festival will be held June 18-21 in Telluride, Colo. Tickets and camping sites are now on sale.