One of Woodstock's great musical voices, John Herald, dead at 65, apparently by his own hand. His group, the Greenbriar Boys, was one of the finest of the New Traditionalist bluegrass groups of the 60s. They memorably backed up Joan Baez on "Banks of the Ohio," and their own debut album on Vanguard spent a lot of time on my turntable. I particularly loved their rendition of "Amelia Earhart's Last Flight" and "We Need a Whole Lot More of Jesus (and a Lot Less Rock and Roll)." John also wrote "Stewball," based on a classic Leadbelly folk song, which was a big hit for Peter, Paul and Mary.
Here's his obit from the New York Times, and here is his page and the Greenbriar Boys page at AllMusic Guide.