I would agree with Jim that the foggy dew of which there are a number of versions with story variations is a fine song, in my opinion john of dreams is also a very good song and s0 is on top of old smokey and tom dooley., all of which are definmed as folk songs
"Maybe so - if I was into that sort of thing I could list you hundreds of Prima Donnas from any branch of music, that fits this description - often with a vegeance (at least one of them lurks through these threads promoting his own abilities like a born-again Colonel Tom Parker) - it really doesn't make the slightest difference to defining what they do."   
the above statement has little relevance to defining folk song, but illustrates an unnecessary level of unpleasantness that is all too familiar in discussion of folk song. jim appears to be unable to discuss without periodic rudeness