Not all of it is, since the lower parts will be close to the ground. But if you look at the pics for the Bosco Verticale project in Milan, you'll see two towers raising their trees right up there.
In addition to being pleasant to behold, the two towers will help purify the city air, increase bio-diversity and protect residents from the sun and noise pollution, [say the designers].
That doesn't answer the really important question, which is: will the Magic Faraway Tree be in amongst all those others?