Cernunnos - Tree Sketch

I made a body armature for Cernunnos. My art doll sculpts usually begin with a head, because it's easier to sculpt the head whatever size I like it and then make the body match. Human figures are usually measured in head-heights (a normal man is 7 1/2 heads tall, for instance). I run into problems when I make animal heads for my human figures because the head height isn't obvious. I have to do a bit of guessing to figure out a total height that makes the funky head shape fit on the human body. If I've guessed right, Cernunnos has a total height of 26". Big sculpture, oi. He'll be sitting, so the final product won't actually be that tall. But it's still going to be a big sculpture.

Anyhow, I also started an armature for the tree he's going to be sitting on. His seat determines his posture, so I need to make some progress on the tree before I can really work out his body. Once I'd started the tree armature, I realized I had no clue what I was doing. I've never sculpted a tree before! So it looks like I have a little more research work to do. I started with a quick sketch of some gnarled tree roots from a photo I found online. Sketches teach me a lot about form, so I'll probably have to do a few more of these before I get the tree sorted out in my head.