Joan Baez songs: Just terrible.
Love the '60s. Love Dylan. Think hippies (sometimes) get a bad rap. HATE the Joan Baez songs in SILENT RUNNING. Granted, I'm not a fan of hers. I think she's probably the single most grating, sanctimonious, cloying, liberal, holier-than-thou singer/songwriter of the '60s EVER (followed closely by Peter, Paul & Mary). But her songs, while on their own may be considered decent by some, just DO NOT FIT in the film and probably instantly dated the film about 48 hours after it was originally released in March of 1972.
I wasn't expecting a STAR WARS-type soundtrack (I realize it was released 5 years earlier), but actual songs WITH LYRICS don't work in a sci-fi film, regardless of the content/context. In SILENT RUNNING, these songs stick out like a sore thumb and just generated snickers of disbelief from this viewer.
(Otherwise, a damn fine film with arguably Bruce Dern's best-ever performance.)