The lone tree with its winter bareness looks wonderful against the twilight blue sky. I do wonder why you included quite so much foreground; for me it adds little to the composition. Did you consider taking the photo from a more distant viewpoint? The inclusion of a little more sky at the top would give the tree a bit more space and prevent the composition feeling cramped.
Although I don't mind the distortion from the wide angle lens, I wish that the tree was parked right in the middle of the frame. Right now, it's not centered nor is it following the rule of thirds--and while your sunset colors are amazing, that minor compositional detail is distracting. I like how you chose to include the field of rocks in your image, it gives a nice sense of depth and space. Overall, a nice image--7