Tree Trimming FAQ’s

Why do trees need to be trimmed?

Umatilla Electric Cooperative trims trees to minimize the likelihood of safety hazards and power outages. During high winds, strong thunderstorms, or snow or ice storms, limbs and even whole trees can fall on electric lines, tearing down energized lines and equipment. Broken limbs can cause outages just by making the right kind of contact with electric lines and equipment.

Usually, when homes are built, an easement is granted at the time of development that allows utilities the ability to access and maintain their equipment. Umatilla Electric Cooperative may therefore hold easement rights on the land on which power lines and poles are located. Umatilla Electric Cooperative requests landowners not to encroach on the easements with trees or buildings that may disrupt the operation of the lines.

Why did you trim so much of my tree?

Faster growing trees will require more clearance than slower growing trees. Smaller, slower growing trees will require less trimming and are more suitable to be planted closer to electric lines. Umatilla Electric Cooperative takes into consideration what type of species the tree is, how fast the tree will grow, how close it is to the electric lines, and the type of voltage running through those lines. The required distance between vegetation and power lines varies from line to line depending on the voltage, local ordinances, tree characteristics, and the tree owner.

Why don’t you trim less and come back more often?

Umatilla Electric Cooperative has three tree-trimming crews working year-round. In determining our maintenance cycle, we consider our objective of providing safe, reliable service, as well as the costs involved. The costs of maintaining the electrical system, including tree-trimming costs, are recovered in our rates. It's a balance of providing you a safe, dependable electrical system while keeping costs within reason.

Why can’t you shape trees while trimming them clear of lines?

The directional pruning method we use is endorsed by the International Society of Arboriculture. Directional pruning, also known as lateral trimming, removes only those branches that conflict with power lines. Rather than cutting limbs back to unsightly and unnatural stubs, branches are pruned back to the center of the trunk where trees normally shed them. Future tree growth is directed away from the power lines.

Directionally pruned trees are less susceptible to disease and insects, and the overall structure of the tree is stronger and more resistant to high winds and ice. Although the shape has been altered, it is recommended over topping or rounding of trees, which tends to promote quick re-growth of small, weakly attached shoots. We are in the business of providing you with safe, reliable power, and we have a responsibility to do that in an environmentally sound way.

Why can’t you put the line underground?

In older neighborhoods with overhead lines, placing lines underground is difficult and expensive. Many trees are already well established. Placing power lines underground would require Umatilla Electric Cooperative to dig into the roots of the trees, possibly causing immediate harm and making them susceptible to disease.

Converting overhead facilities to underground requires considerable trenching of existing pavement, roads, or other structures. Placing lines underground can cost many times more than what it costs to install power lines overhead.

How can the public help to reduce the frequency of outages?

First, understand that Umatilla Electric Cooperative trims trees as a service to our customers as an integral part of our goal to provide you with safe, reliable electric service. Second, try to keep an open mind when our line clearance crews explain why trimming is occurring. Finally, by allowing our contractor to use the proper trimming techniques, your trees remain healthy, and the re-growth from the tree will tend to interfere less with power lines.

How does Umatilla Electric Cooperative decide when to prune?

We have a routine maintenance program for trees and brush growth around power lines. In cases where tree conditions are worse, a line that begins to show an unusual number of tree-related outages may be trimmed sooner than originally anticipated.

Can I prune trees myself?

Never attempt to prune trees near power lines yourself. Only qualified line clearance tree contractors are allowed to work within a minimum of 10 feet of high voltage lines. If there is any question, call Umatilla Electric Cooperative at (541) 567-6414 for an inspection of your tree and line situation.

Phone and cable company lines, those usually found in the lowest position on a pole, do not have clearance requirements, because they do not carry any significant electrical current.

May we have those chips?

Yes. Wood chips are generated from trees that have been trimmed. These wood chips are available to customers, and can be delivered at your request when tree crews are in your area.

These wood chips consist of multiple tree species, are irregular in shape and color, and can include some twigs and rakings. For more information call Umatilla Electric Cooperative at (541) 567-6414 or toll-free (800) 452-2273

When is it necessary to remove a tree?

In some cases, Umatilla Electric Cooperative may have to remove trees that we deem a high risk to electrical service or to the general public. Fast growing trees under power lines, those that require pruning more than every four years can interfere with electrical service and cause power outages. A contractor from Umatilla Electric Cooperative will notify the homeowner regarding the need for removal.

What if I have a complaint about your tree trimming policies or procedures?

Customer and property owner complaints regarding any aspect of the vegetation management program will be addressed promptly, fairly, and professionally. Contractor crew leaders will notify UEC’s right-of-way supervisor of customer or property owner complaints on the day received. UEC’s right-of-way supervisor or designated employee will contact the complaining party within 10 business days of receipt of the complaint.

Can you offer any advice for planting trees to avoid being in conflict with power lines?
  • Remember, before you plant a tree, look up for power lines and call the *Call Before You Dig* toll-free line (800) 332-2344 to locate any buried lines.
  • Be sure to select a good quality tree that is free from damage or disease. Fall is generally considered the best time to plant.
  • The hole should be no deeper than the height of the root ball, and the width of the hole should be at least twice as wide as the root ball.
  • Remove any string or twine or burlap that might interfere with the tree’s normal development. Also, remember to cut any encircling roots that might girdle the tree.
  • When backfilling the hole, use the soil removed from the hole without the addition of any amendments such as peat moss or potting soil. The soil should be tamped down firmly, but not to the point of compaction.
  • Apply two to four inches of mulch to the surface surrounding the tree to help retain moisture, but do not pile the mulch up against the trunk of the tree.
  • Water thoroughly and repeat when rainfall is absent for more than a week.