Over the past two weeks, we have worked in several different landscapes ranging from the edge of native forest to the edge of a busy city street. We have worked on trees that were planted intentionally or unintentionally; trees that have been cared after for many years and trees that were abandoned and left to their own devices. It is difficult to define exactly where the native and urban environment starts and stops. Many times the merge is unclear, or challenging to decipher. Sometimes one landscape swallows up the other. Sometimes it is where the sidewalk ends. It can be challenging to manage green assets when decisions are driven by socioeconomic motivators rather than purely ecological factors. Arborists are left with unique dilemmas and experiences in managing trees under these complex circumstances.

Peter Del Tredici, in his book Wild Urban Plants of the Northeast, provides three different categories into which urban landscapes can be classified: remnant natural, managed horticultural and abandoned ruderal (13). Generally speaking, the three functional classifications define a scale of disturbance; remnant natural landscapes being the least disturbed ecologies persistent from a time before the surrounding landscape was developed, to the abandoned ruderal landscapes having the highest level of disturbance and change from the native ecology (an Ailanthus growing out of the sidewalk crack). Del Tredici admits that the urban setting has been changed so drastically that “most urban habitats…are strictly human creations,” (14). But the three characterizations do provide a working classification system that can be applied to the process of management and to the concept of site overlap that I’ll explore here.

On a private, lake front property we recently cabled a mature Red Oak to add supplemental support to two major stem unions. The current homeowners had been there for a few years, and confessed that they fell in love with the tree that framed the view of the lake from their back deck. It is a hard tree to not fall in love with. It’s flanked on the rocky bank by Red Maples and many other oaks at an elevation of around two thousand feet. It’s architecture is unique, broad and sprawling, left to its own devices of growing in an openly exposed site at the water’s edge.

Aside from the construction of the cottage, I would consider the site to be minimally disturbed, and I would classify this tree as a remnant natural tree, a relic of the native setting that existed on the site before any development took place. In fact, the lake was an ice lake at the beginning of the twentieth century, and was marketed as a summer vacation site around 1949 after developers purchased it from the prominent Lewis family (https://www.mrmlpa.com/IceLakes). Perhaps the tree dates the transition of the site’s economy from a commodity based commerce to a real estate and tourism based commerce. Either way, as a remnant natural tree, it influences the emotions of people in a positive way and gives them a sense of home, inspiring them in their financial decisions because of its deep roots in the past and what that invokes in people’s sense of place and belonging. ‘This tree is a good investment’ is the sentiment.

The tree not only occupies its space on the lake shore, it occupies a space in time over the last seventy or so years of history. The supplemental support system adds strength to structure, but it also adds strength to the plot of a continuing of a story. As a mast tree it has helped wildlife thrive in this ecosystem. Birds of prey have hunted fish from the scaffold limbs. Families have picnicked under its shade on spring and summer days. The tree is a microcosm of this larger place, a time capsule in which the years are locked into its growth rings. It tells the story of drought, heavy winds, insect and disease infestations, and it tells the story of sunny days and growth. The tree has brought people to the lakeshore like a temple draws pilgrims up a mountainside. In this sense I think that remnant natural landscapes and pieces of them are holy things.

Del Tredici writes that “enormous variety of non-human life has managed to crowd into cities to form a cosmopolitan collection of organisms that is typically more diverse than that of the surrounding non-urban areas,” (13). He’s telling us that urban landscapes are more diverse than their rural counterparts, a fact that always gives me pause.

The city is a dynamic place. As an arborist, our interactions with people reveals their feelings towards trees. The scope of emotions is broad, and can range from positive relationships like the example described above, to negative stressors like fear, anxiety and even anger.

One place that conjures up mixed emotions is the tree lawn, that gray area in the urban landscape that is sandwiched between hardscapes and riddled with small root space, poor drainage, compacted soils from storm water run-off, and constant exposure to infrastructure development and public ridicule. It is a land yet claimed by anyone, it is the last frontier for the arborist. It is a crossfire. Some city ordinances claim that the homeowner is responsible to manage trees there. But, oh Lord, my budget. The populace raise up with lighted torches to such claims, and march down to city hall, and shout hideous cries at the shade tree commission. All the while the trees grow on somehow in the tiny soil space between brilliant lawns and black pavement. Norway Maples and Red Maples and Silver Maples and Sugar Maples, Sycamores, Lindens and Little Leaf Lindens, Liberty Elms, Japanese Lilacs, Pin Oaks, Honey Locusts, Cherries and Ginkgo; their root plates spill out over the sidewalk and heave it up, and the shade from their crowns cool it down, and their branches tangle up within cable lines and high speed internet cables. They graft around guy wires. Utility contractors brutally cut their roots, cars crash into their trunks, city workers and homeowners loethingly lop their branches, and the trees grow on, sometimes quite unaware that there is any melee whatsoever. There is a flash of strength in their sprouts. Their leaves bring a breath of fresh air, and with their blooms we smell the hope of another year. Hope, though, is not a plan.

Property lines are another interesting phenomena, another arena of conflict between trees and people. Recently we worked along two separate property lines, and to me they seem to be a place where the edges of managed horticultural sites blend together to form small slivers of abandoned ruderal landscapes at that seam. And typically that seam is a fence, and all the better if it is chain link for the trees spouting and growing there. Del Tredici notes that fence lines act as safe sites for establishment of trees and plants he refers to as ‘spontaneous vegetation'(17).

We performed some crown reduction work on a Gray Birch tree that was tucked into the the corner of a chain link fence in the back yard of a residence. The fence line was trellising wild grape vines, bittersweet, and protecting several young stems of Norway Maples as well. All spontaneous vegetation. Next to the fence was both rhododendron and yew shrubs, cultivated varieties mingling with the outsiders leaning against the fence. There was a squirrel nest present in the crown of the Birch too. Maybe they were the horticulturalists here, the sowers of seeds. The Birch was beginning to grow into the roofs of the houses it grew between, and so it was our responsibility to host an intervention. Many times it seems as though that’s what working along property lines shakes out to be, an intervention.

The very next day we worked along another property line. The scope of work included raising the crown of a maturing Pin Oak, and clearance pruning in an Elm as well as in a mature European Beech. The elm tree was spontaneously growing out of the fence line at the edge of a mature yew hedge, causing quite a bulge on the bottom edge of the chain link. ‘What came first,’ I thought to myself, ‘the elm or the fence?’ It was planted by the wind, or a bird riding on the wind maybe. The Elm was a ruderal being in an otherwise managed horticultural setting, at the compete mercy of chance. The European Beech was the neighbor’s tree, a mature and magnificent feature of a managed horticultural landscape, like an elephant growing up out of the earth. Although the Elm was much younger than the Beech, their life stories had come to an intersection at our clients roof line, and so we added a paragraph to the story in the form of two and three inch reduction cuts.

Before starting the work, I went next door and knocked on the neighbor’s door in order to ask for permission to be on their property for setting lines in the Beech tree and accessing the reduction cuts at our clients’ roof edge. I explained our process and a little bit of our philosophy and keeping the cuts as small as possible and utilizing a non-invasive climbing system. And he gathered my advice on a few other trees on his property over the course of our small talk. ‘Isn’t that tree magnificent’ he said again as we admired it from the porch. ‘It’s a wonderful tree’ I agreed. I was anxious to ascend into the crown and explore the world up there. But then he revealed to me something really wonderful. What he really loved most about the tree, he said, was the dark bold carving that the previous homeowners left on the thin gray bark facing his window: two names encircled in a heart.