Fred Gosbee's grandfather was a woodsman in Maine and always sang really high and spoke the last line of the song.
In some of my rooting around I found a reference to speaking the last line in the ancient bardic tradition as a way of "breaking the spell" that music creates, grounding the song and bringing it into the present. I'm sure the woodsman had no idea of this consciously, although that is certainly the effect it has.
I'll try and find that reference
cheers- Julia