I responded to them earlier and have done interminably Nick
In the main, we don't have the slightest idea where these songs originated (including 'Rosebud in June' by the way), that they appeard on stahe or on broadsides is no indication that they wren't adapted from earliest songs
That is not my point, which is that now songs that have experienced an oral tradition in any way. shape or form are now claimed as folk songs and being given Roud numbers - which was my reply to your question

"please will you give me a title of one song you consider to be a Folk Song"
Work your way through those which appeared on teh aforementioned 'Folk Songs of Britain' Series
I'd happily sit through an evening of them raher than Victorian tearjerkers like Nellie Dean
Jim