From www.stefanoboeriarchitetti.net/en/project/vertical-forest/ -

The first 'Vertical Forest', built in Milan in the Porta Nuova area, consists of two towers that are respectively 80 and 112 metres high, housing a total of 800 trees (480 first and second stage trees, 300 smaller ones, 15,000 perennials and/or ground covering plants and 5,000 shrubs, providing an amount of vegetation equivalent to 30,000 square metres of woodland and undergrowth, concentrated on 3,000 square metres of urban surface.

The project is also a device for limiting the sprawl of cities brought about through a quest for greenery (each tower is equivalent to about 50,000 square metres of single-family houses). Unlike “mineral” facades in glass or stone, the plant-based shield does not reflect or magnify the sun’s rays but filters them thereby creating a welcoming internal microclimate without harmful effects on the environment. At the same time, the green curtain “regulates” humidity, produces oxygen and absorbs CO2and microparticles.

The concept behind the Vertical Forest, that of being a “home for trees that also houses humans and birds”, defines not only the urban and technological characteristics of the project but also the architectural language and its expressive qualities.

A few years after its construction, the Vertical Forest has given birth to a habitat colonized by numerous animal species (including about 1,600 specimens of birds and butterflies), establishing an outpost of spontaneous flora and fauna recolonization in the city.

So many benefits arise from surrounding oneself with nature. The residents of the Vertical Forrest in Milan have been overcome by the birdlife and the tranquility the forrest provides.