Hi, Linda:

Unless you're as famous as George Harrison, you're not likely to have any problems. When someone writes a song, they draw upon all the music they've ever heard, and often phrases surface from old songs without our ever realizing what they are until later. I've had that happen many times... a melody line from Oh, What A Beautiful Morning mysteriously appeared in one of the songs I wrote, and I just finished a song where parts of the melody are suspiciously similar to The Great Pretender. Unless you lift a melody completely, I don't see any problem. And if you're Bob Dylan, you can lift the tune comnpletely and not have a problem.:-)

One of the beneficial side effects of the lack of commercial viability of folk music is that you don't really need to worry much about inadvertently (or even intentionally) using a pre-existing melody. I'd just enjoy the song, sing it for friends and if they enjoy it, the song will be passed around... the greatest payment of them all. Or, you could consider changing your name to Public Domain.:-)

Jerry