2012
2013
Trimming large branches from a middle aged tree can result in undesirable suckering and lead to further problems
as the tree ages.
beetles — can cause significant stress and damage to a smaller tree. Not all pest problems
require arborist intervention,so be aware of what
pests are typical on this species in your area, and
which are cause for concern.
Middle age trees
For trees of middle age,the adage of "a good
defense is the best offense" holds true.There are
invasive pest problems,such as emerald ash borer
or hemlock woolly adelgid, that will attack and
kill a tree regardless of its health; however, a vigorous healthy mature tree does a great job of
fending for itself. Monitoring for insect and disease problems is still important for trees of this
age. If you do find a pest that requires professional services,be on the lookout for predisposing
stress conditions that lead a tree to being more
susceptible to them.This is also the age where
urban trees begin to really give back and provide all the benefits we love from them.Keeping
them healthy and keeping an eye out for pest
problems will be an investment that pays off.
Old trees
Just as humans become more susceptible to
pathogens as we age, so do trees. Monitoring for
pest problems at this age is as critical as it was
for young trees.Not only are these trees prone to
opportunistic pests such as boring insects, decay
inspections should become a regular part of these
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visits. Decay is a leading cause of failure in larger, older trees but it is often predictable and
preventable with regular monitoring. Decay is
nearly impossible to manage once it is established, so minimizing wounding, including
pruning wounds, is important at this age. Even
foliar diseases, such as anthracnose, can have a
more serious health impact on an older tree than
a tree in the growth phase of its life.As with
every stage of life we have discussed, an ounce
of monitoring and preventing issues is worth ten
pounds of cure.
No tree lives forever, and we are well aware
that trees in the urban environment live significantly shorter lives than trees in natural settings.
There are, however, many ways by which an
arborist can influence the health of the tree to
get as many useful, productive, and safe years
from that tree as possible. Educating the tree's
owners on the simple steps they can take is also
an important part of a tree care professional's job.
After all, most tree owners don't notice problems until it is too late, and the trees are unable
to ask for help.This is why it's good that tree
doctors still make house calls.
Brandon M. Gallagher Watson is director of
communications at Rainbow Treecare Scientific
Advancements, and is an ISA Certified Arborist
(#MN-4086A).
Arbor Age / October 2013
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