I seem to remember singing this song from a book (could have been Lomax) and the line where Groves appears in church "dressed in his oil of green." Is that correct? Anyway, seems that oil of green must have been some kind of coat along the lines of what Robin Hood wore - Lincoln Green. Maybe this coat was oiled for the rainy weather that comes with roaming through the forests in the England of olden days? What do you think?