You may not know this, but there is phenomenon in London you don’t see in capital cities around the world. It surrounds a unique tree that thrives in inner cities called the plane tree. Here in London the trees shown here have been ‘docked’, pollarded if you will. They are not there to provide shade but to clean up the air of pollutants that would otherwise create the filth you inevitably associate with any large conurbation. The characteristic bark is often mottled in varying shades as lime green flakes that fall away in the growth and girth of the tree. The plane trees line the streets, almost every street just as shown, and in the summer they give a lovely passage for people to walk beneath as they travel to school and work.
I am always amazed that natural solutions exist even though for the main part we are oblivious to such wonderful benefits.