The foreground trees look strange to me. They're much shorter than those in the background, and much less realistic (just a trunk with a green cloud on top). It would also be nice if there were more variants - there appear to be twelve of the same tree in that area
Also, there seem to be a couple of inaccuracies in linking the border trees at the bottom? There are clear segments that have been linked together, so it doesn't look like a smooth, natural, continuous effect.
And maybe the grass looks too short for deep forest.