www.arborage.com Arbor Age / May 2014 9
ness Program (EHAP). Candidates must complete the require-
ments of the EHAP training program, and TCIA will issue a
certifi cate of completion, which is valid for one year. Each year
a renewal process, with unique training content for a fi ve-year
interval, must be completed.
Understand utility line clearance
Utility arborists face unique challenges when pruning
around utility lines. Because of this, it is critical that a tree
worker understand the fundamentals of pruning around utility
lines before he or she begins working in the fi eld.
Pruning is done for a specifi c purpose — to keep veg-
etation from contacting and causing problems with electric
utility lines. As a utility system arborist, I do not work for a
tree care company, even though I have a forestry education
and specialize in tree care. I work for a company that de-
livers safe and reliable electric power. This is an important
point to remember. While we follow all pruning and tree
care best practices and genuinely care for the health of our
street trees, the overall objective of tree work for a utility
is unique.
Utility line-clearance is done on a cyclical basis. A popula-
tion of trees along a set number of miles of power lines must be
continually maintained. To facilitate this maintenance, pruning
work is distributed over a set timeframe where maintenance
objectives (such as system reliability, safety, customer satisfac-
tion and cost) are evaluated. Often this is a four- or fi ve-year
cycle — meaning only one-fourth or one-fi fth of the total
lines are pruned each year. This cycle setup means there will
be a gap in time where the trees are not reviewed or moni-
tored. Workers must think of the pruning "window" or time
interval before they will be back again to do work. What is
the health of the tree being worked? Will it rapidly deteriorate
and become an issue over that four- or fi ve-year timeframe?
Unfortunately, utility programs do not usually have the ability
to visit and evaluate trees every year like a concerned home-
owner may have the ability to do. This changes the amount of
risk that may be acceptable, and ultimately changes the work
performed on the tree.
This brings up the fact that utility pruning is done on
trees that are owned by someone else. Unless the utility
owns the land where line-clearance pruning is being per-
Before planting any tree, choose a species and location that keeps the tree clear of overhead and away from underground electric lines.
Graphic provided by Unitil