The City is an Apple Tree, in: Porous City

The City is an Apple Tree

“The tree of my title is not a green tree with leaves.” This is the introductory disclaimer to the title of Christopher Alexander’s rejection of the city being a tree in 1965 (Alexander 1965). His tree represents an abstract structure of city organization, which he compares to another, more favourable structure: the semi-lattice.
The tree in my title, however, is meant to be a real tree with green leaves and full of delicious red apples. My tree is standing on my plot, however, right at the edge of my neighbour’s yard. It is fall and the branches have started to hang low with all the heavy fruits on them. This is my tree since it is rooted on my property. I enjoy looking at it, but even more I enjoy the prospect of eating all these apples. One day my neighbour shows up, approaches the tree, and picks an apple. And eats it right in front of me. How can he? The idyllic moment is spoiled. It is only an apple, but here a topic much bigger than this particular scene emerges. It is one of the most fundamental questions of our collective idea of city. It is the question of what is mine, and what is mine but could potentially be used by or affect the others around me, commonly known as my neighbours. And my tree is not an abstract thought but one of several elements in the city that frequently and literally transgress property lines and question our modern idea of land ownership and property, as they might have one owner but more than one user, or at least others that are affected by it, positively and negatively.