When it comes to trees, human beings tend to like them big and tall and inconceivably ancient. …But human beings cut down old trees all the time, for no reason but the inconvenience of their falling leaves or their burgeoning fruit, or because they are in the way of a road or a subdivision, or because of foolish notions of safety. …I wonder what the world would be like if we could harness the outrage engendered by a tree felled in an act of vandalism, or the grief engendered by a tree at risk of dying in a wildfire, and turn it toward protecting the trees we still have left. …Today is Earth Day and Arbor Day is on Friday. Both will be celebrated across the country by a great communal effort to plant trees. …We just need to remember how good it feels to sit beneath the cooling shelter of mature trees, too. [to access the full story a NYTimes subscription is required]