with power lines: V-cutting, side pruning and under pruning. ... is growing into a
power line, it may need removal. ... else touches a downed power line that is still.
Power Lines
Directional pruning includes three main techniques to remove branches that conflict with power lines: V-cutting, side pruning and under pruning. These pruning methods not only remove the conflicts but also lessen the need for future pruning. Illustrations of each are shown below: V-CUTTING Consists of cutting back a portion of the tree’s crown.
BEFORE V-CUTTING
AFTER V-CUTTING
SIDE PRUNING Consists of cutting back or removing side branches.
BEFORE SIDE PRUNING
AFTER SIDE PRUNING
UNDER PRUNING Involves removing limbs to allow wires to pass below.
TREE RIGHT AFTER V-CUTTING
Power Lines
Power Lines
3 YEARS AFTER V-CUTTING
8 YEARS AFTER V-CUTTING
When is tree removal needed? Removing a tree may be necessary because of disease and insect infestation, or because there is little chance of the tree developing a natural structure or stability. If a palm tree is growing into a power line, it may need removal. That’s because palms grow rapidly and, unlike trees with branches, they have only one growth tip. If a tree poses a threat to human life or property, removing the tree is necessary. Children climbing a tree near a school or park risk injury or electrocution if that tree contacts a power line. And finally, NEVER attempt to trim trees near power lines yourself. SDG&E provides tree trimming services for free to its customers to ensure a safe and reliable energy source.
For more information
BEFORE UNDER PRUNING
AFTER UNDER PRUNING
At first, these target or directional pruning techniques may, in some cases, make the tree less pleasing to look at. However, these techniques reduce the number of sprouts and the chance of disease, improving the long-term health of the tree.
At SDG&E we are committed to providing safe and reliable energy. If you have questions or concerns, please call us at 1-800-411-SDGE (7343). S A N D I EG O G A S & E L EC T R I C P. O . B OX 1 2 9 8 3 1 S A N D I EG O, C A 92 1 1 2- 9 8 3 1 1-800-411-SDGE (7343) w w w. s d g e . c o m
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Do your trees need pruning? SDG&E’s Vegetation Management Program
Why does SDG&E need to trim trees? If not properly maintained, trees near electric power lines can cause problems, both for you and for San Diego Gas & Electric (SDG&E). The SDG&E Vegetation Management Program trims trees growing under or next to high-voltage power lines. Here are the reasons:
For your safety – It prevents electrocutions! SDG&E – and all utilities nationwide – regularly trim trees near primary power lines for the safety of the public. When a tree or a large branch falls on a power line, as sometimes happens during storms, it can bring down the power line. If you or anyone else touches a downed power line that is still energized with electricity, it can cause serious injury, even death.
This tree will not grow taller than 25 feet. It will not interfere with power lines and does not need trimming.
It helps prevent fires!
It’s required by law!
When a tree branch contacts a power line, it can cause a fire. SDG&E works closely with the California Department of Forestry and with other fire agencies in our service territory. To prevent fires, we work together to identify those trees that need trimming.
SDG&E and other utilities in the state are required to achieve clearances from primary electrical power lines in accordance with the California Public Utilities Commission General Order 95 – Rule 35. In addition, trimming within State Responsibility Areas must be completed to achieve compliance with the even stricter Section 4293 of the Public Resources Code.
It helps prevent power outages! Tree-wire contacts, especially with palm trees, are a major cause of power outages in SDG&E’s service area. By trimming trees, we help to prevent power outages. That increases the reliability of your electricity service.
These trees will need trimming. The branches could interfere with the wires and cause fires or power outages, especially during storms.
How is the tree trimming carried out? The trimming is done according to arboricultural standards and in compliance with Section 4293 of the California Public Resource Code by local trimming companies supervised by International Society of Arboriculture (ISA) certified arborists. Directional pruning techniques, promoted by the ISA, are used to retain the natural shape of the tree and reduce sprouting of weak branches.
Some trees cannot be trimmed properly, like this palm, and will have to be removed. Blowing and falling palm fronds are a major cause of outages.
