A flock of sheep grazing in the shade of a tree


© Marek Biegalski


How much is the shade of a tree worth? Our cities are gradually turning into vast deserts of cement, with hectares of green destroyed by the inexorable consumption of land. Soon we too shall be like these sheep in search of shade from the sun in the Tuscan countryside. As summer days become hotter and more suffocating, our cities will imprison more and more heat even after the sun goes down. In our metropolises, skyscrapers already prevent the free circulation of air and provide an immense surface area for the absorption of solar radiation. This causes the “canyon effect” – vertical corridors that retain heat because of their dark surfaces and multiple reflections between opposing façades.
Trees are a precious capital for our cities. Hackberry, elm, ash, linden and maple trees have an excellent capacity for storing carbon dioxide and for capturing and absorbing various pollutants, yet how many avenues, once tree-lined, do we now find laid bare? On the subject of heat, tree shade is actually a lot cooler than that produced by awnings and other artificial structures. Solar energy is absorbed by the plant’s biological processes and the foliage changes the direction and speed of the wind without preventing the passage of air. We need to understand that our frantic lives are still interwoven with the branches of trees and protected by the priceless generosity of their leaves.

Andra Meneganzin