This is a very good concept and well accomplished. You might be interested in Green Man in my gallery that I carved (in Lime which I think is Linden.)
Assuming that the serpent is carved as part of the same block, how did you darken the wood of the serpent?
I did a serpent twisted around a tree trunk and I darkened it over a fire and then sanded away the burn marks in the surrounding trunk. Primitive, eh?