Here, at ArchDaily, Vanessa Quirk argues that the practice of drawing trees on top of skyscrapers in architectural renderings should stop. First, because pretty, high-altitude foliage is the first thing that cost-conscious developers jettison when the actual building is underway; but secondly, because trees can’t really survive at that altitude …
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On the other hand …
Certainly in Vancouver elevation for growing trees is not a problem, but it is important to note that trees require enough soil/medium to grow…and they need much more than grasses and sedges….so having roof top trees is a lot more expensive than having just a ‘green’ roof.