Celebrating living trees instead of fake trees seemed like a logical
first step. In fact, trees might be our single best tool for urban
salvation. City dwellers get most excited about two natural features:
water and trees. Now fans can even write emails to trees in Melbourne
(“As I was leaving St. Mary’s College today I was struck, not by a
branch, but by your radiant beauty. You must get these messages all
the time. You’re such an attractive tree.” The trees, which are tagged
with individual identification numbers in St. Mary’s Park, sometimes
write back via the park crew).
My man Olmsted understood this devotion. In his principles for
park design, he thought no features should stand out as too distracting
or spectacular. There should be no flamboyant flower beds and only a
minimal amount of overt architecture. The magic formula: generous
meadows loosely defined by trees. Winding pathways leading to
mystery, flirtatiously half concealed by trees. Trees, trees, trees. They
were so important to the Olmsted schema that he ordered no fewer
than 300,000 of them for Central Park’s 800 acres, effectively
freaking out his budgetary overlords. There were so many trees and
shrubs that Calvert Vaux had to recruit a small team of family and
friends to fill in the master drawing with tiny green spots. This was
pixelation, circa 1858.
Urban trees provide not just aesthetic pleasure but concrete health
benefits. Although certain species of trees can worsen asthma through
pollen and other compounds, taken as a whole they generally improve
people’s physiology in several important ways. Public officials
perhaps didn’t fully appreciate this until a rather astounding study
was published in 2013. Geoffrey Donovan, an urban forester with the
U.S. Forest Service, spotted an intriguing natural experiment: a pesky
scourge called the emerald ash borer, a “phloem feeder,” landed on
our shores in about 2002, whereupon it decimated 100 million ash
trees throughout the Midwest and Northeast. Gone, poof. Donovan
decided to see if there was any relationship between the treepocalypse