AUB’s Tree Trimming Program

A Year-Round Necessity to Ensure Reliable PowerATE trucks

“Why is my power out?!” We’ve all come to expect our electric power to be there with complete reliability. So, when it does go out, we want answers.


 All too often, the answer for the question above is that a tree or limb has either bumped or fallen on a power line. Downed lines are one of the top reasons for power “blips” and outages. They also are a safety hazard and a big expense to every customer.


 At AUB, when it comes to working on problem trees we're not really in the "tree trimming" business; we are in the "power line clearing business."  We try to maintain a three-year trimming cycle.  If we trim your trees this year, we shouldn't be back for another three years.  That's why it is critical to get proper clearance each time we trim.


 If not maintained to ensure proper clearance for power lines, the same tree or group of trees can knock out power to hundreds of customers over and over again. Who wants to pay to fix the same problem over and over again? The best way to avoid that scenario and control tree-related costs is to properly trim the culprit trees and keep them well away from power lines.


  The basics of our program

  • AUB has a certified arborist on staff ensure best practices in tree trimming for the health of the trees and the reliabiltiy of the power grid pursuant to ANSI-300, the nationally recognized standard for proper vegetation maintenance around power lines.
  • AUB's arborist personally notifies property owners of planned trimming prior to the work; during emergencies, such as when a tree has fallen, this may not be possible.
  • Trimming is free of charge to the customer;
  • Customers have the option to arrange for an independent contractor at their expense to trim their trees to AUB specifications prior to AUB contract crews trimming their neighborhood/street. However, if a property owner chooses this option and then does not follow through with getting the trees trimmed, AUB will return to trim the trees and must then charge for the work;
  • AUB trims trees according to the best-recognized and approved principles of modern tree surgery. See below for details.
  • Limbs and/or branches will be cut flush with the supporting trunk or limb so that no stub is left. This method, called “lateral pruning,” is healthier for the tree than the old “rounding over” method;
  • Trees will be trimmed to a minimum clearance of 12 - 15 feet. Limbs may be cut farther from the lines to comply with lateral trim methods;
  • The premises of the property owner will be left as neat as before the trimming; our crews will chip the resulting brush and small limbs, but larger limbs and/or trunks are the property owner’s responsibility. AUB will cut limbs and trunks to short, manageable lengths for the property owner.
  • Limbs that are overhanging power lines will be trimmed as high as possible. All efforts will be made to eliminate weak, diseased, and dead limbs that may fall or blow into the wires;

 Trimming trees around service lines (the lines running from the customer’s house to the transformer) is the property owner’s responsibility. For your convenience and safety, AUB crews will disconnect those lines free of charge at your request when you want to remove or trim a tree near them and then will reconnect the lines when called. Call (423) 745-4501 to request assistance.


Lateral Pruning

For Trees Fit and Trim

 Pursuant to best practices for healthy trees, AUB does not "round over" trees.  Not only is it bad for the tree's health, there is in fact no need for ratepayers to pay to trim the side of a tree that is not near power lines.


 Though rounding over is common, it is not healthy for the tree. It encourages wood decay in the remaining stubs. Plus, the rapid growth of sprouts means the tree has to be trimmed again in no time, increasing overall trimming costs. 


 AUB uses the lateral trimming method, which has been standard practice in the tree-trimming industry for decades. Lateral trimming is simply removing the offending branch back to the closest lateral branch that is growing away from power lines. The wound on the branch is smaller and heals easier, reducing the possibility of decay. Lateral trimming may result in removing branches beyond the required minimum 15 feet of clearance.


  For more information regarding effective and healthy tree trimming methods, visit the website of the National Arbor Day Foundation.