Nice work. The colour choice was obviously a big part of this piece, guessing from the title and I think they are always good ones to use. It gives the piece a natural almost earthy feel. Anyway, the way that you have made the hair so realistic is amazing and I'd very much like to know how you did that.
My only criticism is that the colours could have done with a little bit more blending as at some points, the neck being an example of this, they seem to be a little too cartoony for such a realistic piece. Other then that it's great.
Keep it up.