Folk music is making a comeback after the success O Brother Where Art Thou?, but it tends to be the more "authentic" branch and less pop. The recordings here of the traditional love song John Riley are from the era of more pop style singing. The TV show Hootenanny featured mostly younger acts, though they sometimes had on people from Pete Seeger's generation. I'm not sure they would have gone for "old timey" acts like the Stanley Brothers or the Cox Family, but I must admit the show is one of those things I've half forgotten.
The next version is from Joan Baez.
And the first version I ever heard was from The Byrds. They are now remembered as a druggie lyrics and jangly guitars, but they were deeply connected to the folk music scene. I love the harmonies here, which I think are close to the style of madrigals. This version is without the string section overdub added to the album version and is repeated for reasons unknown. You will also hear a record skip unfortunately. As much as I love the Byrds' music that is still remembered, this may be my favorite of all their songs.