Well. Depends who you ask.
Norway maples, callery pear, ailanthus, ash. Spotted lanternfly adores laying its disgusting eggs on the bark of the ailanthus, commonly known as the tree of heaven.
So ailanthus deserves to get whacked. But what about grape vines? Apple trees? These host the same invasive insect.
As for the callery pear, you might have some gracing your downtown sidewalks or your apartment complex. Offering bright white blooms for a week or two in early spring. Arborists’ assessmen: Pyrus calleryana is a nightmare. Why? Inquiring minds (mine) have investigated. These trees, originally from China, were widely introduced by landscapers in the 1960s, and displace native trees and plants. Also, they don’t smell sweet, as you would expect them too. Communities around the U.S. can’t cut them down fast enough – some are even offering rewards to those who destroy them.
Ash trees play host to another noxious bug, also imported from Asia, known as the emerald ash borer. Cities are eliminating dead trees by the thousands as well as infected ones as a kind of stay of execution. Last year I accompanied a crew in Queens that was feeding axed ashes into the chipper.
Whole blocks were decimated, and once-graceful allees of mature trees vanished, much to locals’ shock and confusion. Everywhere these strange diagrams exposed by peeling bark, the sure sign of disease.
Where is the tree I grew up with, whose branches swayed outside my window my whole life? No more birdhouses.
Thinking about the nature of bad and good trees as I stand in the grueling heat of an early Queens morning. The parade of Norway maples along 145 Street in Flushing provides the only shade separating residents from an New York-style Hades.
People tend toward puzzlement when the sidewalk crew comes along. Are they taking down our trees?
Don’t get me wrong. Sunshine is good! If you asked medical pioneer Florence Nightingale, she would have touted its healing properties. In the nineteenth century, she espoused the wondrous effects of sun and fresh air in the absence of cures we take for granted, antibiotics and penicillin and the like. One approach in the 1930s was to suspend a babe in need of fresh air out a tenement window!
But today, what we now call the heat island effect afflicts neighborhoods like this one in Flushing disproportionately. They need all the cooling they can get. Even the shade of the “invasive” Norway maple plays a part.
Researchers have noted that individuals with mental health issues (e.g depression, for example) are more at risk when faced with high temperatures and “need to take extra care” as cognitive performance has been shown to be differentially affected by heat. People with diabetes, are overweight, have sleep deprivation, or have cardiovascular/cerebrovascular conditions should also avoid too much heat exposure.
Residents need shade. These trees, in the words of an arborist friend, are working hard. And they’re not getting paid, either!
What’s the use of being house proud, like so many Queens-ites, if you haven’t any trees?
Residents love their flowers.
Some even plant small-scale farms – more ambitious than my raised tomato beds.
But others bake. The heat island effect means that people are cooked, literally, in their homes and neighborhoods. Fried like so many sidewalk eggs. Within the United States alone, an average of 1,000 people die each year due to extreme heat.
Mainly poor people. Those without recourse to decent air conditioning, swimming pools – and trees. Trees are a necessary feature in combating most of the urban heat island effect because they reduce air temperatures by 10 °F and surface temperatures by up to 20–45 °F.
Buildings, roads, and other infrastructure absorb and re-emit the sun’s heat more than natural landscapes such as forests and water bodies. The process of taking up water through its roots, up through the leaves and out again as vapor into the air, called transpiration, is something all trees excel at. It’s nature’s air conditioning. Canopy cover is always important, but nowhere more than in the places where it can’t be taken for granted.
In the suburbs we have grand old tall cedars.
In urban areas, not so much.
Nothing makes up for the simple, absolute value of coolness in hot weather.
Some surprising trees make it to a good old age on these mean streets. A Siberian elm somehow thrives in a 4×4 inch tree pit.
I stand outside a nondescript bungalow on 107 Avenue.
There is a robust swamp white oak. How nice.
These are some of the exotics you might stumble across in the boroughs of New York. Older specimens have obviously offered shade to strollers for quite some time. London planes thrive in the most destitute circumstances, and we are all the better off for it.
When you hear about property owners razing “good trees” to build additions or housing projects or basketball courts, it’s common sense to mourn their loss. Mature oaks, sweetgum, lindens don’t just spring up overnight and surely don’t deserve to be disappeared. We know we need them, though some knuckleheads will always come along to say they don’t matter and remove them.
But what about the specimens sometimes dismissed as trash trees? Are honey locusts expendable simply because they are so common in this city?
I think that logic is mistaken. Honey locust has its own sharp-shouldered beauty.
Even the city version without the spikes can make itself welcome as a shade tree where we need shade.
Trees can’t help the species that spawned them, or the whims of the city planners who once planted these sometimes struggling urban forests. A Norway maple has gotta right to live too! And we deserve their shade. All of us.
Jean Zimmerman 