Looks fantastic to me. Like baccaman pointed out, it could be a little too constrasty. It looks great, but if anything were to walk on it in a game, this way it looks too "rigid". But as a stand-alone tile, I think it looks great. It's not too dark at all, it looks like something that would fit in a dense, misty jungle type environment.
Baccaman is heading in the right direction if it's supposed to have something walking on it. Then it could do with less contrast to make it look more like a flat surface, so a character walking on it won't look like it's hovering above all the grass.