As Bill Clinton nearly said, it all depends what the meaning of 'the' is. There's 'the green man' as in 'the conventional figure of a wild man or man of the woods'. Then there's 'The Green Man', a singular personification of the natural world, who our forebears are thought to have actually believed in.

Am I right in thinking that whether the green man had any association with foliate heads is a separate question from whether The Green Man did?