I'd love to have somebody ask Jean Richie post to this thread. She's had to deal with copyright in the past as a way of protecting the songs that have come down through her family.
BTW, one of the saddest moments I've ever had was when I showed Ed McCurdy a compilation album of cuts from his famous "When Dalliance Was in Flower" record series. (for those not familiar with it, this is a five record series of 18th century songs that Ed researched for months in the New York Public Library. The series is an example of loving scholarship, and thanks to his hard work, the songs have gone "back into the tradition"; they're being sung at many a Renaissance Faire and historical re-creation gathering) Ed said,"I didn't know this record existed." He was not a wealthy man. I'd gotten the record because I saw his name on it. He deserved better for his work.