Need a serious bluegrass fix? How about 12 hours of it? That’s what’s on tap for the Bluegrass Marathon Jam, featuring music from top regional bands. They include Copper Ridge, Cary Street Ramblers, East of Afton, Some Assembly Required, Highway 249, Old Dog New Tricks, Notch 8, Willis River Band, Jackass Flats, Slack Family Band, Green Boys, River City Band, Rattlesnake Creek, Red Light Rodeo, Heavy Duty Bluegrass, Some Assembly Required, Red Light Rodeo, Creekside Pickers, Hometowne, and Scattered, Smothered and Covered. There also will be a few open-stage sets, during which all comers have a chance to show off their picking skills and plenty of room to just strike up a good old-fashioned jam. The event benefits the Fisher House at McGuire Veteran’s Medical Center, a home for families of veterans receiving medical care. The Marathon Bluegrass Jam takes place at the Cultural Arts Center at Glen Allen on Saturday, Feb. 23, from noon to midnight. Donations accepted. rvabluegrassjam.com.