Home Jambase Audio & Video: Greensky Bluegrass & Umphrey’s McGee Collaborate In AshevilleNational Music NewsJambaseMusicAudio & Video: Greensky Bluegrass & Umphrey’s McGee Collaborate In AshevilleFebruary 18, 2017241FacebookTwitterPinterestWhatsApp Members of Umphrey’s McGee and Greensky Bluegrass shared the stage together last night at Exploreasheville.com Arena.