Butterworth's 'Banks of Green Willow' is a truly beautiful work. It does indeed include the melody of 'Green Bushes', but also two different variants of BOGW, one major and one modal - the modal one is from David Clements of Basingstoke recorded in 1909 (bear with Mr Clements, he takes a while to get into it):

Clements' version

Butterworth was a good friend of Cecil Sharp and danced in Sharp's demonstration morris dance side. He was one of four of the team killed at the Somme. Sharp was devastated.