Can you spot the glaring problem with this painting

There is one huge problem with this picture.  Can you spot it?  I know that technically There are some problems with the picture, but there is one huge problem.  I didn't realize I had done it until it was time to scan the painting.

I on looking at this painting again, I think I need a shadow from the large pine tree on the left hand side.  I could go back and add that in later.  It's funny what you notice while you are painting and what you dont recognize until later.