This is the latest design in the war against environmental damage.

A group of engineers from Nectar in California have designed a skyscraper that it hopes will become a gigantic filter for the sky - undoing pollution generated by all the other skyscrapers.

Basically it holds about 200-400 large trees that absorb pollutants and converts CO2 into nice, clean and breathable oxygen.

It is made of concrete and includes a windmill powered water system that gives the trees the water and nutrients they need.

There are no plans for its construction yet, but its designers hope one day it will spring up near some of the world's worst polluting factories.