Avoiding Tree & Utility Conflicts
Determining where to plant a tree is a
decision that should not be taken lightly. Many factors should be considered
prior to planting. When planning what type of tree to plant, remember to look
up and look down to determine where the tree will be located in relation to
overhead and underground utility lines.
Often, we take utility services for granted because they have
become a part of our daily lives. For us to enjoy the convenience of reliable,
uninterrupted service, distribution systems are required to bring utilities
into our homes. These services arrive at our homes through overhead or
Overhead lines can be electric, telephone, or cable television.
Underground lines include those three plus water, sewer, and natural gas.
The location of these lines should have a direct impact on your
tree and planting site selection. The ultimate mature height of a tree to be
planted must be within the available overhead growing space. Just as important,
the soil area must be large enough to accommodate the particular rooting habits
and ultimate trunk diameter of the tree. Proper tree and site selection provide
trouble-free beauty and pleasure for years to come.
Overhead utility lines are the easiest to see and probably the ones
we take most for granted. Although these lines look harmless enough, they can
be extremely dangerous. Planting tall-growing trees under and near these lines
eventually requires your utility to prune them to maintain safe clearance from
the wires. This pruning may result in the tree having an unnatural appearance.
Periodic pruning can also lead to a shortened life span for the tree. Trees
that must be pruned away from power lines are under greater stress and are more
susceptible to insects and disease. Small, immature trees planted today can
become problem trees in the future.
Tall-growing trees near overhead lines can cause service
interruptions when trees contact wires. Children or adults climbing in these
trees can be severely injured or even killed if they come in contact with the
wires. Proper selection and placement of trees in and around overhead utilities
can eliminate potential public safety hazards, reduce expenses for utilities
and their rate payers, and improve the appearance of landscapes.
Trees are much more than just what you see overhead. Many times,
the root area is larger than the branch spread above ground. Much of the
utility service provided today runs below ground. Tree roots and underground
lines often coexist without problems. However, trees planted near underground
lines could have their roots damaged if the lines need to be dug up for
The biggest danger to underground lines occurs during planting.
Before you plant, make sure that you are aware of the location of any
underground utilities. To be certain that you do not accidentally dig into any
lines and risk serious injury or a costly service interruption, call your
utility company or utility protection service first. Never assume that these
utility lines are buried deeper than you plan to dig. In some cases, utility
lines are very close to the surface.
Proper Places for Trees Around Homes
The illustration indicates approximately where trees should be
planted in relation to utility lines. Your garden center staff or tree care
professional will gladly help you select the right tree.
Trees that grow as tall as 60 feet (20 meters) can be used in the
area marked as the tall zone; however, you should consider your neighbor’s view
or their existing plantings of flower beds and/or trees.
Plant large trees at least 35 feet (11 meters) away from the house
for proper root development and to minimize damage to the house or building.
These large-growing trees are also recommended for streets without overhead
Street planting sites must also have wide planting areas or medians
[greater than 8 feet (3 meters)] that allow for a large root system, trunk
diameter, and root flare.
Large trees are also recommended for parks, meadows, or other open
areas where their large size, both above and below ground, will not be
restricted, cause damage, or become a liability.
Trees that grow up to 40 feet (12 meters) tall can be used to
decorate or frame your house or provide a parklike setting. Select your trees
first, then plant shrubs to complement the trees. Medium-sized trees are also
recommended for planting anywhere the available above and below ground growing
space will allow them to reach a mature height of 30 to 40 feet (10 to 12
meters). Appropriate soil spaces are wide planting areas or medians [4 to 8
feet (1 to 3 meters) wide], large planting squares [8 feet (3 meters) square or
greater], and other open areas of similar size or larger.
This zone extends 15 feet (4.5 meters) on either side of the wires.
Trees with a mature height of less than 20 feet (6 meters) may be planted
anywhere within this zone, including street tree plantings under utility lines.
Such trees are also recommended when the growing space is limited. These trees
are appropriate as well for narrow planting areas [less than 4 feet (1 meter)
wide]; planting squares or circles surrounded by concrete; large, raised
planting containers; or other locations where underground space for roots will
not support tall- or medium-zone trees.
Some Further Suggestions
Plant evergreen trees to serve as windbreaks on the west or north
side of the house, approximately 50 feet (15 meters) or more from the house.
Plant deciduous trees (those that drop their leaves in the fall) on
the south and/or west side of the house to cool in the summer and allow sun to
enter the house in the winter.
Right Tree—Right Place
Planning before planting can help ensure that the right tree is
planted in the right place. Proper tree selection and placement enhance your
property value and prevent costly maintenance trimming and damage to your home.
For further information on planting and helpful tips on tree selection, refer
to ISA’s brochures on tree selection and new tree planting. If you have any
more questions, please contact your local ISA Certified Arborist or tree care
professional, utility company, local nursery, or county extension office.
E-mail inquiries: email@example.com
(c) 1998, 2004 International Society of Arboriculture.
UPDATED JULY 2005
Developed by the International Society of Arboriculture (ISA), a non-profit organization supporting tree care research around the world and is dedicated to the care and preservation of shade and ornamental trees. For further information, contact:
ISA, P.O. Box 3129, Champaign, IL 61826-3129, USA.
E-mail inquires: firstname.lastname@example.org
© 2007 International Society of Arboriculture.
UPDATED SEPTEMBER 2005