Tree Management
Our Campus Trees:
A Focus on Tree Vitality
Presented by the Mount Holyoke College Botanic Garden and the Mount
Holyoke College Department of Facilities Management
Maintaining a Healthy
Tree Canopy
The trees of Mount Holyoke College have long been
admired as part of our beautiful campus landscape. Maintaining the
health of these trees is an ongoing collaboration between the Botanic
Garden and the Grounds Department, with input from certified arborists
as needed. A large percentage of the trees on campus were planted
at the same time in the 1940’s, replacing trees lost during
the hurricane of 1938. The many changes to the campus over the last
60 years have stressed many of the trees resulting in a tree canopy
that is in decline.
Community Concern
Knowing many in the MHC community are concerned about
campus trees, we thought it would be helpful to give you more information
about the process of tree management. Every tree on campus is in
the Botanic Garden’s database. Included in the database is
a description of the health of the tree with an assessment of overall
health as excellent, good, fair, or poor. Trees in the poor category
are inspected annually to determine if any have become hazardous,
and need to be removed.
The primary reason trees are removed is safety. The generally accepted
definition of a hazardous tree is: “a tree with structural
defects likely to cause failure of all or part of the tree, which
could strike a ‘target.’ A target can be a vehicle,
building, or a place where people gather such as a park bench, picnic
table, street, or backyard.”1
Besides hazardous trees, some trees need to be removed as part of
construction projects, and, in spite of appearances to the contrary,
we work very hard to save as many trees as possible. Any tree small
enough to move has always been relocated to another site on campus.
In some cases, utilities have been rerouted to avoid damaging tree
roots. Tree removal is only done as the last choice.
Planned Tree Take Downs
Please see our campus map showing trees that have
been removed in the past year, trees that have been planted in the
past year, and hazardous trees, some of which will be removed in
the current year.
Planting for the
Future
Because there had not been a tree planting program
for many years, during the 1990’s the Botanic Garden and Facilities
Management planted nearly two trees for each tree removed. Now we
plant one tree for every tree removed. Sometimes the replacement
tree will be planted in the same location; at other times we might
determine that the original site is unsuitable for a tree. In this
case, a tree will be planted at another location on campus.
Everyone on campus can help us preserve the health of our trees
by keeping vehicles off the lawn areas, especially around trees.
Most trees have roots that reach far beyond the spread of their
canopy, and most roots are in the top 18” of soil. This means
most of our campus is criss-crossed with tree roots. Even pedestrians
can have an impact. Continual use of non-paved paths will compact
soil and negatively impact tree health.
While tree removals are unavoidable, we can all help prolong the
lives of our trees, and leave the legacy of a healthy landscape
for future members of the Mount Holyoke College community.
If you have any questions or concerns about campus trees, please
contact Ellen Shukis, Director of the Botanic Garden at x2199, or
via email.
| Tree
Management questions or concerns?
Please contact:
Ellen Shukis, Director of the Botanic Garden at x2199,
or email.
What
is a 'hazardous' tree?
“a
tree with structural defects likely to cause failure of all
or part of the tree, which could strike a ‘target.’
A target can be a vehicle, building, or a place where people
gather such as a park bench, picnic table, street, or backyard.”1
In
context of this quote, 'failure' of a tree refers to a tree
not being able to support all or part of itself upright anymore,
at which point all or part of the tree may fall over and hurt
passersby or damage property.
In
context of this quote, 'structural defects' may include poorly
healed trunk wounds, which indicate areas of unhealthy tissue
that are susceptible to infection; fungal or bacterial infections
that render the wood soft, spongy or hollow; cracks in the
trunk, which indicate areas of structural weakness, as well
as increases susceptibility to infection; cavities in the
tree, which significantly decrease tree strength, may collect
water and cause rot, and increases susceptibility to infection.
In the context of the above quote, 'structural defects' weaken
the overall strength of the tree trunk, branches and roots
to the point where the tree may fail, and fall over.
Why
does the Botanic Garden and Facilities Management remove campus
trees?
Campus
trees that have been repeatedly evaluated as 'hazardous' by
the Director of the Botanic Garden and a consulting arborist
are removed to prevent accidents from occuring on campus.
Our desire is to maintain a safe campus. This is the only
reason we are removing these hazardous trees. Already, the
campus community has had some near misses with falling limbs
and trees. The Botanic Garden and Facilities Management have
decided that the safe course of action to take is to proactively
remove diseased, decaying, structurally unsafe, 'hazardous'
trees, instead of watching them fall down around us. |
1.
Minnesota Department of Natural Resources, and USDA Forest Service.
1996. How to Recognize Hazardous Defects in Trees. USDA Forest Service
NA-FR-01-96. 20 pp.
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