Why didn't you leave out the limb in the upper right corner? I like your image but this limb covers a great looking cloud. Narrows the space the image needs to work imho. Anyway: a cool shot!
Not a bad shot. Could use a bit more constrast and I would have tried to shoot so that the bit of branch in the upper right corner were out of frame. The curve of the ridge line is very pleasing as is the placement of the tree itself. Nice work.
I find the tree tough to pick out. The bright spot at the top is really what draws my eye and so it's hard to settle on the tree as subject. I think it meets the challenge, but the tree needs to be brightened up some.