"Boeri acknowledges that there is an alternative model of “green architecture”: design solutions and “smart appliances” for capturing energy and channelling that are invisible behind smoked glass and steel frames. Put another way, a building can meet the new environmental guidelines without the planting of a single shrub. But the “living architecture” movement goes beyond the current legislation: it is about how cities should feel."
Wondering what the high velocity winds would do to the trees on a tower like that. Seems that the root system would be rather shallow and well winds whipping around at 90 mph at ground level would seem to be much higher with the elevation of the tower so I'm supecting you might have winds exceeding 100 mph. I can only imagine trees being ripped off the 20th Floor and falling to the ground below onto unsuspecting people below. It would be alot worse than pigeon poop.