The trunk needs some work: I'd like you to make the trunk the same color as the text and give it the same type of shine that's on the text. Go to Apple.com and see the iPad2 text. See how the highlight is slanted? See the color? Look at design #52. See how the Trunk has that same glare?
On the base of the trunk, please make that smooth. I see what you're trying to do there--making it look like dirt. But it needs to be smooth like glass.
Do something different with 2 pointed branches on the trunk. Can you either make them more flat or take them off entirely? The points just don't match with all the other rounded elements.