I can find no mention of this song on Google, so hoping someone here knows it. I have heard it sung a couple times around Boston, USA. This is the chorus, to my best recollection:

And now the wolf cries long and low, and the wind upon the hill
The stars shine cold, and the moon grows old, and the earth is wrapped in chill
Gone the robin from the oak, and the holly sings the wren
Come rain and snow, when the warm winds blow, the oak will grow again