What a perspective! Good for you, for attempting a difficult angle. I would argue however, that is a little too tilted. Actually. When I turn my head to the side, and force myself to look at the canvas sideways, I'd say the perspective looks much better! Its easier to tell that its a tree, and the depth actually improves!
Things farther away will have less detail, so the base of that trunk should be a little less detailed, while the foliage on the tree would be your focal point. This will help to push your depth.
As far as color goes though, this is the first piece I've seen from you that really has a good concept with color and atmosphere.
Something that would help to ground this a little better, would be a horizon line. ( Defining line that would help to separate the ground from the sky.) There's a faint one in the background, I can see it! But I would push it a little bit more.
Nice work though! I can see the amount of time you've put into this. Certainly more defined and complete than the first works I've seen. Keep up the good work!