Moss walls for better air in Berlin

The limits of polluting agents are constantly being exceeded in the German capital. A start-up has developed an idea for the improvement of air quality: moss walls. A 12 m² moss wall has the same regulating effect on fine dust thatn 275 freshly planted trees. In addition, this concept --named "City Tree"-- costs 95 % less than trees and requires 99 % less surface. The Berlin senate seems open to the idea for now.