HI Manfred,
There's something visually odd about this shot.
The lighter shades on the bark suggests the light is coming over your right shoulder, however, the shadow is suggesting the light must have been coming over your left shoulder.
An alternative explanation would be that the tree shadow doesn't belong to the tree in shot, but to another, out of frame to your right.
I couldn't really determine the reality from grass clump shadows.
I was also intrigued/distracted by the tracks and whatever that is on the ridge line of the dune near the top.
If your intention was that I should study this for several minutes and scratch my head (unwise!), you succeeded