Hey everyone, I'm trying to make a rather large tree and I need some advice on the roots/trunk. Here is a what I have so far:

This is for the front yard of a house that is isometric. To me, it looks as though it is made for a non-iso

. I'm not sure how to manuevuer the roots around to make it look like its actually coming up out of the ground. also if there is any shading/dithering advice you can offer it is also welcome. I can't wait to put some leaves on it. That's gonna take forever.
If anyone knows any good tree tutorials or pictures that i can study for further reference please post a link.
thanks!
toshiomagic