I like the style of the wooden fence, however, the trees completely miss the same style. Therefore, they the fence together with the tree will look akward.
The wooden fence is nice, however, I suggest letting some of them look like they go into the ground.
The trees are very unrealstic. Trees rarelly ever crop up like that without any holes showing whatsoever. I suggest looking at some pictures of trees.
Also, they look rather more like a beveled square then spherical shaded. Especially the shading on the middle tree reminds more of a beveled square.
Think of the trees as circles. And shade them like so:

The underside is not the darkest because light beams bounce of against the ground, back on the underside of the tree creating a light spot there.