Why Aren’t We Saving the Urban Forests?

The volunteer black walnut sapling in our front yard arrived courtesy of a local squirrel. Deep into its third spring, it looks like the kind of tree a child would draw: a narrow trunk topped by a ball of leaves. I had to mark it with a little flag to make sure my husband didn’t mow over it by accident. 

As with all the other trees that have appeared in our yard through no effort of our own, I am besotted with this squirrel-planted young walnut. The baby Eastern red cedars and the baby black cherries and the baby red mulberries were all planted by birds. The baby sugar maples were planted by the wind. Some day they will be all food for the creatures who share this yard. (The baby willow oak and the three baby shingle oaks that appeared two years ago have already fed the rabbits.) 

This black walnut won’t reach full maturity for another 150 years or so, and that’s if no one cuts it down — a bet I would not take. Most suburban Americans prefer a lawn unpocked by nuts and unvisited by birds, a square of nature that belongs to nothing natural. 

When it comes to trees, human beings tend to like them big and tall and inconceivably ancient — preferably growing at some pretty distance. Trees are meant to grow in community with other trees, but for many people the ideal tree stands alone in an otherwise desolate landscape, tucked next to a dip in an old stone wall or visible across the vastness of fallow fields. 

Last summer, in the days after a catastrophic wildfire in Maui, Hawaii, Lahaina’s historic banyan tree was rightly a focus of concern far beyond the island. When vandals cut down the legendary Sycamore Gap tree in Britain’s Northumberland National Park last fall, that too caused an international uproar. 

These were movie-star trees. For us they had ceased to be a part of the nameless, inscrutable forest and become instead themselves. A living organism. A friend. 

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. The fear of a falling limb has cost many a suburban tree its life. In the 21st century we have become so separate from the natural world that we don’t feel safe in the presence of perfectly healthy trees. 

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. 

The overwhelming majority of Americans live in cities. In an analysis of 44 U.S. cities by the nonpartisan nonprofit Climate Central, roughly 55 percent of the study’s population live in neighborhoods with an average temperature that is at least eight degrees higher than it is in the surrounding rural areas. This phenomenon, where the built human environment is even hotter than the rest of the rapidly warming world, is known as the urban heat island effect. In New York City, the urban heat island index is a whopping 9.5 degrees. 

We know forests can capture and sequester carbon before it adds to the heating climate, and we know we need to protect the forests we still have. But too few of us understand the crucial contribution that trees make in our cities and suburbs: cooling hot buildings, preventing storm-water runoff, improving air quality, pulling carbon out of the air, and the like. Not even to mention the habitat — food, shelter, nesting sites — that trees provide our wild neighbors. As the proliferating seedlings in my own yard attest, trees are an essential part of the ecosystem for local wildlife. 

Newly planted saplings can help, but with nowhere near the same effectiveness as mature trees. And yet we have somehow gotten the idea that planting a tree in urban and suburban areas has the same practical effect and moral force — there, I said it — as preserving one. A tree is a tree, right? If one happens to be growing in a place where you don’t want it to grow, just cut it down and plant another in a more convenient spot. 

In rapidly growing cities, where even a robust plan for planting trees can’t possibly keep pace with development, the preservation of existing trees would go a long way toward keeping the city livable for human beings as well as for wildlife. Here in Nashville, we actually have a tree-protection ordinance, though it doesn’t apply to duplexes or single-family homes, where so many of the remaining trees still live. There are ways to preserve the trees on construction sites, of course, but spec-house builders rarely bother. 

As a species, we don’t have 150 years to wait for a black walnut seedling to reach its full glorious height before we start protecting the black walnut trees still among us. The parent tree of my own baby walnut lies across the street from a house that was recently torn down by a developer, along with every tree not in the public right of way. The tree surgeon who carted them off in pieces said the builder’s instructions were to clear every tree from the lot. 

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. 

I get it. There’s something very heartwarming about watching a community come together to install a whole row of ornamental trees on a nature-impoverished city street, or to pick up a free seedling from one of the many tree giveaway efforts that sprout up among conservation nonprofits at this time of year. It feels good to dig a hole to the right depth and the right diameter, to set a baby tree down inside it and pat the soil gently around its roots. We are a tenderhearted species, and it feels very good to nurture a baby tree. 

We just need to remember how good it feels to sit beneath the cooling shelter of mature trees, too. And we need to fight just as hard to save them as we work to replace the trees we’ve already lost. 

Margaret Renkl is a contributing writer for the New York Times and the author of the books “The Comfort of Crows: A Backyard Year,” “Graceland, at Last” and “Late Migrations.” She graciously granted the RSF Post permission to reprint her article.