Boeri Studio will soon realize the dream of the forest tower with Bosco Verticale, or Vertical Forest -- and they're building two. The thought of a tower "built" out of living greenery has been rendered by architects numerous times, it has reached the point where it's considered a trope of green architecture. But from an idealistic view, seeing the tree-tower design get past the planning stage and move toward completion is quite refreshing, if not intriguing, to say the least.

Located in Milan's redeveloping complex of Porta Nuova Isola, Vertical Forest was designed to help alleviate the city's increasing air pollution problem and provide a biological urban habitat in a total area of 40,000 m2.

The towers -- at 110 meters and 76 meters tall -- allegedly have 900 trees (measuring between 3m-6m) already planted in the residential balconies, along with 5,000 shrubs and 11,000 floral plants on terraces up to the 27th floor. As described by the studio, the vast number of plants will not only create oxygen and humidity and lots of shade from harsh sunlight, but they'll also absorb CO2 and dust particles to reduce pollution.

Led by Italian architect Stefano Boeri, the studio worked with Arup to develop the project's structural and geotechnical designs, as well as consultation on acoustics, vibrations, ground-borne noise, and tunneling.

The towers contain units ranging from compact two-room apartments to penthouses and duplexes, with balconies that extend about 3.5 meters outward to provide room for the greenery. Each tower's design also uses photovoltaic energy systems for better self-sufficient energy.

Completion of Vertical Forest is scheduled for the end of 2014.