I think that I shall never see/An urban cooling device as effective as a tree

More trees growing in Brooklyn please--but with some care, and with the participation of the people who really need them

Anyone who’s lived in New York knows that—aside from traffic tie-ups—the residents of the Five Boroughs pay precious little attention to the United Nations. Yes, Biden spoke to the General Assembly yesterday about climate change and covid, and yes the Chinese premier promised an end to financing for coal-fired power plants in other countries. But the front page of the Daily News  (“New Rip on Accusers”) remained focused on former governor Andy Cuomo still trying, pathetically, to discredit the women he’d previously harassed. (The Post covered, among other things, a cancer survivor killed by an exploding beer keg).

New York—especially this week—is the venue for some of the highest level climate action. But it’s also a place that suffers grievously from climate change—and where some very local interventions might make a huge difference. Trees, for instance.

Normally, when people talk about trees and climate change, they use very big numbers, putting forward plans to plant tens of millions or billions or trillions of trees to soak up carbon dioxide and slow the rise of the planet’s temperature. At the moment, the would-be tree-planters are somewhat on the defensive, as scientists point out problems with the vast schemes, including that they’ve become a staple of too much corporate greenwashing.

But there is one kind of tree-planting plan that seems both achievable and clearly helpful—the kind that could happen not on vast steppes or savannahs but in a crowded place like New York. Earlier this year the New York Times (which failed to cover the exploding beer keg, but is still a reasonable operation) reported that temperatures in Manhattan varied widely on a hot summer’s day. In fact, they said, the sidewalk along Central Park West (think the Dakota) was 31 degrees cooler than a street in East Harlem less than two miles away. The difference, of course, was the canopy of trees that line many of the best addresses in New York, or for that matter a great many other cities. The same thing in the Bronx: Mott Haven, a poor section of the borough home to mostly people of color, had seven percent tree cover; Riverdale, with the opposite demographic, luxuriated under 47 percent tree cover. Thirty one degrees: that’s the difference between a summer day and a sauna.


Since people in poor neighborhoods are already more likely to suffer from asthma, cardiovascular disease and obesity, and less likely to have air-conditioning, there’s a mulitiplier effect here too: we lack trees where we need them most.  It didn’t happen by accident: as the Times story pointed out, these were the areas that banks redlined two or three generations ago, and have suffered from underinvestment ever since. Bottom line: “African Americans in the city are twice as likely to die from heat exposure as white New Yorkers, according to the city’s health department.”

Happily, that can be remedied, and not by planting billions or trillions, but by planting perhaps a million trees across the city. That’s a manageable number: one for every seven inhabitants or so. It won’t do much to lower the carbon dioxide levels on the planet—for that we have to stop burning fossil fuel (which will also clean up the air in these enclaves, which is systematically dirtier just as it is hotter). But while that’s happening, we might as well make people as cool as possible.

Of course, even urban tree planting is not as simple as sticking seedlings in the ground. Copenhagen—a city that works hard on environmental planning—set out to plant a million trees in 2015, but “people bash into them with bikes and cars,” Sandra Hoj, an urban tree campaigner in the city, told Bloomberg News. And the political breeze that ruffles the treetops can change: “In both L.A. and Denver, million-tree campaigns started under one mayor failed to reach their target before their successors changed strategies. L.A. had planted 407,000, and Denver, between 250,000 and 500,000.”

Also, you need to actually talk to the people who will live beneath the canopy. In Detroit, many residents surprised officials by saying no, often quite loudly, when the city offered to plant trees on their blocks. Researchers surveyed them to find out why: the opposition, they found, “resulted primarily from negative past experiences with street trees, particularly in low-income neighborhoods grappling with blight from vacant properties. In 2014 alone, the city had an estimated 20,000 dead or hazardous trees, following the contraction of Detroit's once-massive tree maintenance program from budget cuts and population decline.

“For many long-term residents, wariness of the new trees was driven by past experiences of caring for vacant properties in their neighborhood. They believed responsibility for maintaining the trees would eventually fall to them. ‘Even though it's city property, we're gonna end up having to care for it and raking leaves and God knows whatever else we might have to do,’ said one woman interviewed for the study.” Happily, when residents were consulted in advance—and given, say, a choice on what species of tree to plant—acceptance rates went up.

We are getting past the point of gestural politics around climate change: from now on, progress is going to be one solar panel, one induction cooktop, one e-bike—or one tree—at a time. And building community is going to be as important as building a new grid. Everyone deserves the chance to live beneath a tree: it’s not that many generations, after all, since we all swung down out of them. But just as trees make a neighborhood, so it takes a neighborhood to make a forest work.