The tree and apple were not drawn at the same time :  the black paint used for the tree is more faded out than the blue. The word "Art" has been written among the roots of the tree.

This appears to be a very simple drawing but I would be quite unable to do that with spraying paint. It is naive but catches one's eye.

 

 

 

Photograph taken by me in Autun, France, on August 15th 2014.