by Brian Siano
The removal of 24 trees, as part of the long-planned Park A Revitalization, surprised and shocked many of our friends and neighbors. Although we’ve tried to keep people informed via our website, newsletter, Farmer’s Market table and articles in the UC Review, many people were unaware that the changes would be this sudden and this radical. Many people felt that trees which they regarded as healthy should not have been removed from the park.
Clark Park was never a “natural” forest that was simply barred off as a park; it’s a domesticated landscape, and it requires human intervention. Most of the trees, such as the London Planes, were planted more than a hundred years ago to shape the park. Many of the trees were planted because they could thrive in urban (i.e., polluted) environments, and most of them have thrived… for a hundred years.
At an FOCP Membership meeting in 2008, Lisa and Bryan Hanes outlined the strategies for tree removals. Arborist appraisals performed in 2001 and 2008 gave the Haneses a chance to study the progress of the trees in question.
Many of the trees removed were expected to die within the next five years or so. Some had hollow trunks (see photo), making them structurally unsound. A pear tree was removed because of fire blight.
Norway Maples: an Invasive Species
Seven trees, Norway Maples, were designated as an “invasive species,” and were removed. The notion of an “invasive” species of tree surprised many of our neighbors. The Norway Maples looked strong and healthy, and their deep green leaf color made them some of the most attractive trees in the park. They even have a venerable history, because they were introduced to the Americas by no less than John Bartram.
But they are “invasive” because they rapidly take over forest environments. They grow quickly, penetrating existing forest canopies, and their dark leaf color casts a dark shade that prevents sunlight from reaching other trees and plants. Their shallow root systems leach nutrients and water from other plants… and they secrete phytotoxins which damage other plants and trees as well. Many of Boston’s urban wilds are now monocultures of Norway Maples, and Massachusetts and New Hampshire have banned the sale of this species in order to protect woodlands.
The Morris Arboretum strongly suggested that we diversify the species of trees in the park. When the London Planes die, we plan to replace them by planting different species of trees. This becomes difficult when an existing species inhibits the growth of any new trees we decide to plant..
Why all at once?
A look at the downed tree trunks illustrates why many of them were removed. About 40% of this pile shows a great deal of internal rot.
The simple answer is that it was cheaper and more effective to do all twenty-four tree removals when we were also renovating the rest of the park.
Ever since Clark Park was established, it has required periodic maintenance, including tree pruning, planting, and the occasional tree removal. Normally, these haven’t been more than four or five trees at a time, and they don’t happen very often.
To give you an idea of what a tree removal involves, think about the loss of five trees this past summer. The total cost of those tree removals was $41,000. That’s between five and six thousand dollars per tree, and most of those had been torn from the ground already. We had twenty-four trees that were either going to die in the next five to ten years, or were interfering with the health of the park’s other trees.
Perhaps we could simply have let them die on their own, and have them removed one by one as they went. That would have required funding to pay for expensive tree removals, not to mention the hazard of allowing trees to collapse on a heavily-used park. It would also have required heavy machinery to rest on the paths we’re building now, and the work would have to avoid damaging the rest of the park. The Park A project enabled us to take care of these trees all at once, with state and city money, and when the paths and lights were also being rebuilt.