I came across The Oak and the Ash in Andrew Gant's Folk Songs of the British Isles. Here my musical interests cross paths as there is a nice, easy recorder arrangement of this folk song in Folk Songs For Recorders. This another, for me typically English, folk song of the sadder variety. I always enjoy the first illogical line of A north-country maid up London has strayed" as it illustrates the crazy, baffling manner in which English is used in its native land.
Geoffrey Shaw in his National Songs With Descants provides four verses compared with just three in Andrew's work. Are there any more out there?

Lyrics