The mural is by Pierre Alechinsky. The poem, by Yves Bonnefoy, is more or less as follows (my translation):
Passerby,
look at this great tree
and through it,
That can be enough.
For even rent and sullied,
the tree of the city
is all of nature,
all the heavens,
the bird alights there,
the wind moves there, the sun
there expresses the same hope in spite
of death.
Philosopher,
if you are lucky enough to have the tree
in your street,
your thoughts will be less arduous,
your eyes more free,
your hands more desirous,
at least at night.
Addendum, July 27, 2005: This page has had many more visitors than other photos in this gallery. If visitors would leave a comment or e-mail me a note about how they got here or what they like about this photo, I would be thankful!
(December 13, 2011: I had translated "déchiré, souillé" as "torn up, sullied," but on reflection, I think "rent and sullied" is a little better.)