I know I'm in no position to critique such awesome pixel art, being a newbie, but I have two little problems.
1. The highlights on the tree and log just don't work. Maybe you could use the dirt highlights some more?
2. Speaking of the log, it has the same shades as the tree trunk (in the shadow of the leaves), leading us to believe the log is in shadow. However, there is nothing casting a shadow on it.
I hope this helps.
