What is folk anyway?
2
The Oral tradition
Folk songs are common property and the authors as a rule unknown. Oral transmission is at best unreliable, and often (I presume) the people who sang the songs adapted them to their own tastes, tacking stuff on the end to make it topical, dropping or changing stuff they didn't understand or appreciate, whatever felt right. Even those who thought they were loyal to the "original" – the one they had heard – might mishear words or sentences, couldn't remember the exact words and changes crept in and accumulated.
For example one of the ever-popular "come all you fair and tender maids" songs
A woman is a branchy tree / And man's a singing wind
And from her branches carelessly / He'll take what he can find
A nice metaphor – I mean as a song where women warn other women what to look out for as to how men treat women.
Unfortunately the rhyme relies on an old or dialectical pronunciation of the word wind. Not liking the non-rhyme if the word is pronounced in standard modern English, someone (I presume) thought up another metaphor to describe men's behaviour to women. Or perhaps she (/he) was convinced that that was what she had heard, or that it was a better metaphor:
A woman is a branchy tree / And man's a clinging vine
To my tastes inferior, but there you go.