Wrong green

This is an update/re-write of a post that lost its links.

Wish I had got my brain in gear long ago, and done it myself.  In a short but effective article by Tim De Chant at Slate, titled
Can We Please Stop Drawing Trees on Top of Skyscrapers? finally someone has taken the trouble to state the obvious:

Architectural design proposals often depict high-rise buildings with trees flourishing on rooftops in an attempt to look more ‘green'.  Despite this, trees and skyscrapers are a lethal mix – for the trees.  Regrettably, trees rarely survive on the top of skyscrapers, undercutting ideas of including them as a nod to sustainability and environmental friendliness in the renderings.

The article sets out the fundamentals: extremes of temperature, destructive wind velocities, and the immediate threats they pose to the normal biological functions of trees – from structural stability, to delicate osmotic gas and vapour exchanges in the normally protected boundary layer of air.  Anticipating the logistical difficulties of maintenance is not exactly rocket science, either.

The case against trees at great heights is easy to make, and is contrasted with the relatively easy path to conventional roof gardens on lower rise, high density apartment buildings..