Proper vegetation management, including tree trimming and clearing, is crucial for maintaining reliable electric service. When trees come into contact with power lines, they can disrupt service and cause "line loss," where electricity escapes into the ground instead of reaching homes and businesses, driving up costs. More importantly, trees near high-voltage lines present serious safety risks, as they can conduct electricity.

Primary Objectives

We’re driven by two primary goals when it comes to vegetation management.

Accommodation Info

Safety

Maintaining safe, reliable, and economical electric services is our highest priority.

Accommodation

We aim to accommodate the preferences of landowners, within reason.

Tree Trimming Accommodations

Accommodating our tree trimming services can be challenging, especially when individual tastes and concerns are involved. While there are recommended procedures for tree trimming that involve making symmetrical cuts across the entire tree to ensure necessary clearance, these are seldom followed because they are rarely acceptable to landowners. Additionally, trimming the whole tree is more costly, contradicting our goal of providing the best possible service at the lowest possible cost.

As a result, "notching" or "gapping" a tree is more common, particularly with larger trees. This method achieves the required clearance, removes minimal parts of the tree, and is both economical and generally accepted. However, we acknowledge that this approach can be unsightly immediately after the initial trimming. Typically, this visual impact is mitigated by seasonal growth.

We aim to trim trees to provide 3 to 5 years of clearance, usually about ten to fifteen feet. At the same time, we strive to ensure that landowners are reasonably satisfied with this necessary but sometimes undesirable task. Our procedures adhere to industry standards. To reiterate, while clearing and trimming can be unsightly, we endeavor to minimize the amount of tree removal. The initial visual impact is generally mitigated by a season's growth.

More Information

Learn more about our approach to vegetation management.

Policies and Procedures

Why does GCEC prune trees?

For Safety:

Utility vegetation maintenance reduces electric safety risk to the public by:
- Providing minimum separation between wires and vegetation to eliminate potential electrical shock
- Reducing potential wildfire hazards from tree/wire conflicts and downed power lines caused by trees

For Reliability:

Trees are among the most common causes of utility service interruptions. Trees that are too close to power lines can interfere with electric service; especially when weather brings lightning, wind, ice, or wet snow. Maintaining power to vital infrastructures and services such as hospitals, nursing homes, police and fire departments, airports, water and sewer pumping stations and traffic signals is paramount.
Utilities can better assure reliability of electric service by:
- Having a preventative maintenance program that includes removing branches, vines and entire trees and brush from electrical equipment and energized conductors.
- Removing vegetation can potentially cause a safety hazard or an electrical outage when it has the potential to grow into the power lines or fall into them due to weather or poor tree health.

Does GCEC follow any pruning guidelines?

An increasing number of utilities follow the American National Standards Institute (ANSI) A-300 Part 1: Tree, A Shrub and Other Woody Plant Maintenance – Standard Practices, Pruning. These guidelines, endorsed by the International Society of Arboriculture (ISA), promote directional pruning methods which minimize pruning stress and focus on tree health while obtaining necessary clearance from power lines.

How often is utility tree pruning completed?

The time between maintenance activities varies from utility to utility and between different regions of the country. Sometimes the frequency is mandated by the state agency. The best interval for tree maintenance is based on:

Expected re-growth rates of tree species present
Amount of clearance that can realistically be obtained at the time of pruning
State or local regulations
Available program funding

Maintenance cycles are generally shorter where there is a longer growing season or a high percentage of fast-growing tree species. In areas with a short growing season or fewer fast-growing tree species, the cycle can be longer. Some utilities conduct ‘mid-cycle’ pruning and/or inspections to mitigate the fastest growing tree species midway through a cycle.

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What is a line clearance tree contractor?

As defined by Occupational Safety and Health Administration (OSHA), it is a company that is qualified to maintain trees near power lines. These companies employ qualified line clearance arborists who receive ongoing electrical safety training as well as provide equipment and tools that are maintained as non-conductive.

How are utility line clearance arborists trained?

Most tree care workers are not qualified to work near energized power lines. Qualified utility line clearance professionals meet OSHA qualifications and are the only ones who are legally permitted to work within 10 feet of power lines or work on a tree that has branches within 10 feet of power lines. Line clearance arborists are trained to prune trees according to American National Standards Institute (ANSI) A-300 pruning standards and follow industry best practices, which helps preserve the health of trees.

Note: Homeowners should never hire a private tree contractor to work within 10 feet of power lines or attempt to do the work themselves. The utility should always be contacted for information first.

Why doesn't GCEC put lines underground?

Undergrounding of lines is very expensive and results in more difficult (and longer) repairs in the event of a power failure. Also, converting an overhead system to underground typically causes substantial damage to existing trees’ root systems.

Is my tree a candidate for pruning or removal?

Situations where tree removal may be preferable to line clearance pruning include:

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Tall or fast-growing species growing directly under the power lines that require frequent pruning and will never have a natural form – high outage risk
Saplings (brush) with the potential to grow into or close to the lines
Large, previously topped trees under the lines
Hazardous trees (examples – leaning, in decline, severe dieback, cracked or split, hollow, etc)

Does GCEC prune trees in a remote or wooded area?

In remote/rural locations, utilities often utilize mechanical equipment to increase efficiency and worker safety. Large saws mounted on high-reaching booms can be used to prune the sides of right-of-way corridors. In some cases, saws are suspended from helicopters. When using this equipment, it is understood that the quality of the cuts can be less than those made by hand. Nevertheless, efforts are made to avoid unnecessary damage to the tree.

Chemical application is another method of side pruning where herbicides are applied to the foliage of selected branches growing into the right-of-way corridor. The treated branches eventually die and are shed by the tree.

Tree Pruning

What is directional pruning?

Directional pruning removes branches growing toward the power lines while leaving those that are growing away. It is the most appropriate way to clear trees for electric utility line clearance.Trees that are pruned in accordance with ANSI A300 Standards will have branches pruned back to a lateral branch that is at least one third the diameter of the branch being removed. Additionally, cuts should be made close to the parent or main limb to not leave a stub or damage the main limb.

What is natural target pruning?

This is the proper method by which branches or limbs are removed from a tree. The cut is made close the parent branch or limb, but without leaving a stub or damaging the branch bark collar.

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How will a tree look after it is directionally pruned?

Trees growing directly under conductors may appear U or V shaped. Trees growing alongside a conductor may appear L shaped, or one side might be removed from side pruning. The trees may appear misshapen, especially if you are looking down the street. In general, trees growing close to the electric utility lines or facilities will never have the potential to grow with a completely “natural” looking shape.

My trees are not even touching the wires, why do they have to prune them?

Utility companies are proactive and try to prune trees BEFORE they pose a risk to the power lines. Because trees are dynamic, factors such as swaying in the wind, sagging with ice/snow weight, and uprooting in storms are examples of problems that can occur without warning even if the trees are not in contact with wires at this moment.

Pruning trees to direct growth away from wires before becoming problematic is ideal. It may take years before a tree presents a safety or reliability risk, but fast-growing trees near the power lines will need to be pruned or removed completely as they mature.

Why not just top the trees?

“Topping” or stubbing is a detrimental practice that can result in poor tree health and form and is not recommended by arboricultural organizations.

Directionally pruned trees stay healthier than topped trees, have a better form, and require less pruning in the future because of the use of reduction cuts used in the directional pruning method. Certain species of trees, such as conifers, may appear to be “topped” after the main leader has been pruned, however, this does not necessarily have a negative effect on the tree’s health.

How much will be cut from my tree?

Typically, a qualified utility forester or vegetation manager prescribes the amount and type of pruning necessary based on:

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Tree growth rate and structure
Wind direction
Tree species: strong or weak wooded
Tree health or vigor
Environmental factors
Water sources
Proximity of tree to wires and line configuration
Power line voltage–higher voltages require greater clearance

In many cases, we need to remove more than 10 feet of clearance to reach the leader from which the limb is growing, ensuring the tree's health. This allows the cuts to heal more quickly and effectively, benefiting the tree overall.

Planting Guidelines

What should I know before planting a tree?

Planting the right tree in the right place can increase property value and energy efficiency of your home and minimize property damage and power outages caused when trees meet power lines. When planting a new tree, consider where you are placing it and what the tree will look like in 10 or 20 years. Look up from the proposed planting site and see if there are wires overhead or nearby. Also, don’t forget to check for underground utilities prior to planting.

Is it safe to plant a tree near a transformer?

A homeowner can plant any plants they wish around the transformer if they leave the necessary clearance around the transformer (3 feet from the back and sides of equipment and 10 feet from the front). If for some reason GCEC needed to access the transformer and it was covered with vegetation GCEC would have to remove it to secure a safe workspace.