It is a curious fact that from any of the green public benches found throughout the city of Boston, you can see a tree. And there is no starker contrast to be found in the polarized city of Boston than between the trees of summer and the trees of winter. Throughout Boston’s parks and streets, but particularly down along the granite banks of the Charles River, the dreaming trees of summer are as different from the hibernating trees of winter as sunlight is from moon light.

The bench where I sit is the bench where I sleep: a green hardwood bench along the Charles River watershed in Boston. My green bench serves double duty as a place to sit and observe the seasons, and, come bedtime, a place for this “rough sleeper” to spend his homeless nights. My bench is in the vicinity of several river trees I’ve grown to know—and by sleeping between the trees, I know it ain’t skid row! I’m in good company with all the gallant elms, sycamores, lindens, mulberry, crabapple, and maple trees found lining the bicycle paths of the Emerald Necklace.

And I’ve noticed over the years camping out that each of these species has a unique reaction to the environment. It’s as if a tree could have a personality. It saddens me when a favorite tree loses a large limb due to a harsh winter wind; and I wince in the summer when a large, noble, fully-leaved tree snaps and gets knocked over on top of a footbridge, necessitating its destruction in a giant woodchipper. The occasional stump of a tree looks to me like a boarded up & closed business, reminding me that an important community asset has been lost.

Branches stretching skywards towards the light with roots descending into the darkness, the tree is a sentinel of time, a living testament that cannot be recovered if the tree is destroyed by fire or simply knocked over by wind. Silent witnesses to so much Boston history, trees inspire further acts of wisdom: to plant as many trees as possible. Thus, “arborist” is a particularly sagacious vocation.

Cheerfully greening and especially beautiful, the trees of summer stretch up towards the sun like so many cathedral spires. Tall and broad like a circus tent, sacred since time immemorial, summer trees are also companionable, providing protection against a sudden rainstorm or providing shade to enjoy a picnic, and glorious, no matter how insect ridden or gnarly they may be.

Not all trees are treated equally, however. One particular tree from Asia, called The Tree of Heaven (Ailanthus altissima), is classified as a noxious invasive species. Thought to have been brought to the U.S. in 1784, It is found throughout Boston today. Ailanthus altissima is notorious for producing a chemical that retards the growth of other plants (though other trees do this, too), while its roots can damage sidewalks, sewers, and the foundations of buildings (again, this happens with many other tree species, including natives). No tree is perfect, and I can understand that they sometimes need to be removed. My regret is lessened when I realize that more trees are being planted around Boston on a regular basis.

The Charles River estuary is lined with trees, their shiny brass identification tags tinkling in the wind. The early evening darkness is pierced by soft moon glow, silhouetting branches against Boston’s crenellated skyline, reminding me of the strange and disturbing paintings of Gustave Doré, or an old Civil War daguerreotype, a bleak scene in shades of gray.

All trees serve some purpose in the judgement of the arborists who plant them or the neighborhoods that demand them. There are approximately 125,000 trees in the entire city of Boston, and more than 35,000 of these are street trees. Healthy public trees provide much more than shade: they filter air pollution, contribute to climate control, store rainwater and reduce erosion, connect the city to various ecosystems, and provide stable habitat for beneficial insects, birds, and animals.

As I limp around the city of Boston, pushing my shopping cart ahead of me in my homeless pilgrimage, the days of tree watching go by slowly, while the years feel quick. I make my way along the footpaths of the Charles River basin, noting the work done on trees. Most of the round brass tags nailed to the trunks have blown off in the winter, while those which remain show various I.D. numbers. Newly planted saplings have plastic tags snapped around their branches, identifying them by species: Northern Red Oak, Swamp White Oak, Little Leaf Linden. I have come to know the trees by the shapes they take, the pattern of their leaves, and the shade or protection they offer. My favorite trees provide deep shade in the searing sun, dense foliage against the down pouring rain, or wide trunks to offer protection against the sudden winds of a violent squall. Those three types of trees I consider my friends.


Kevin Walker is a lifelong Bostonian, now homeless more than twenty years, giving him “perspective on a different side of the city,” he writes.


From “free” to “friend”…

Established in 1911 as the Bulletin of Popular Information, Arnoldia has long been a definitive forum for conversations about temperate woody plants and their landscapes. In 2022, we rolled out a new vision for the magazine as a vigorous forum for tales of plant exploration, behind-the-scenes glimpses of botanical research, and deep dives into the history of gardens, landscapes, and science. The new Arnoldia includes poetry, visual art, and literary essays, following the human imagination wherever it entangles with trees.

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