I think it's much more trunk-like now! The form is much clearer and it looks round, and you've even got a nice twist to it near the bottom. It would look even better with a bit more contrast between the three browns, and maybe some more hue-shifting.
It looks a bit noisy to me still, though. At this scale, the bark texture is essentially noise, so I think you might be better off not depicting it, and instead focusing on the larger shapes, like the twist of the trunk, burrs, etc. If you prefer the noisy look, then I think you should avoid having the single-pixel highlights right next to the darkest brown, as it reads more like sharply jutting features (thorns?) than just bark texture. That's a good technique for something like a cactus or a studded mace, but doesn't look quite right on this tree.
A visual illustration of what I mean by it looking like it juts out too much:
The bottom sketches represent the apparent size of the bump represented by the different levels of contrast.
The left and middle sketches represent a mild bump like what you'd expect to find in the texture of a tree trunk, the right/high-contrast bump doesn't feel as natural for a trunk texture.
Also, the roots don't seem to go into the ground, they appear to end abruptly. That is probably because of the shadow/outline on the tops. Try not having the very tips shaded, it should look more like they smoothly enter the ground.
