Really like this shot. Again I think your levels are slightly off. It might be that your screen calibration could be off and it looks perfect on your screen.
Its always best to use the levels in Photoshop to check that the whole tonal range is being used. If there are flat spots on either side just drag the corresponding slider until it starts to rise.
By the way where is this tree? Ive been after a solumn tree for ages and can never find one lol