[corresation]

Ignoring the environment while planting a tree anyway, is the opposite of being truly ecological or truly green.

He is doing exactly the opposite of ignoring the environment. Again, your haughtiness is transparent and doesn't make you sound like an expert, but more an armchair expert (which is not an admirable thing).

How many trees in nature grow on spires that are 100s of times higher than their base (hint: trees that grow on mountains do not apply. Mountains are wide enough with a shallow enough grade that they carry their own ground effect. A skyscraper does not), raising hundreds of meters above ground level?

Zero. None. Nada.

This discussion has nothing to do with enclosing tropical plants in polar areas. It has to do with trees environmentally exposed 100s of feet in air. Completely exposed to an incredibly hostile environment. It is enormously impractical.