Vegetation Management

Vegetation is a vital natural commodity.  It provides needed shade in summer, helps clear the air of pollutants, provides a home for wildlife and pleases the eye with the beauty of its foliage and blossoms.  When vegetation comes close to or in contact with utility power lines, a potentially hazardous situation is created often resulting in an electric outage.  While vegetation is the cause of many outages, trees and power lines can coexist.  To control the frequency of outages, PES establishes the following guidelines:

A.    PES will maintain the following minimum clearances between vegetation and power lines in non-manicured areas:

  • Twenty-five (25) feet of clearance on each side of distribution lines
  • Thirty-seven and one-half (37.5) feet on each side of transmission lines
  • Ten (10) feet clearance around open secondary service lines
  • Six (6) feet of clearance around insulated secondary lines

B.    PES will maintain the following minimum clearances between vegetation and power lines in manicured yards:

  • Ten (10) feet horizontal clearance and six (6) feet of vertical clearance from energized lines
  • Any tree or tree limb in that “hazard zone” will be subject to removal, although PES tree crews will take into consideration the tree species, hardiness and speed of growth
  • All trees planted directly under electric lines in manicured yards must be on the approved tree list, available at the PES main office
  • To maintain optimal line accessibility, no woody-stemmed plants may be planted within twenty (20) feet of utility poles.  While PES will make every effort to avoid trees and shrubs, landscaping within twenty (20) feet of the pole may be damaged during typical maintenance and will not be replaced by PES.
  • Ten (10) feet below the mounting height of all yard lights
  • For underground services, six (6) feet of separation is required between all customer shrubs, trees and fences and PES pad-mount transformers.
  • Two (2) feet of clearance around meter bases.

C.    Prior to maintaining the right-of-way, PES will attempt to contact the property owner using information available to PES.  PES will only recognize the property owner or his/her pre-established designee as an individual having authority to make permanent decisions concerning the alteration of property.

D.    PES will be responsible for all repairs to property damaged while maintaining the right-of-way unless the damaged property infringed on the designated right-of-way area defined in the policy.

E.    PES will remove all debris trimmed using handsaws, and will rake clean any manicured areas.

F.    PES will use the lateral pruning method that is outlined in the American National Standards Institute (ANSI) A300 standard.  The National Arbor Day Foundation, International Society of Arboriculture (ISA), and National Arborist Association recommend this standard.  Lateral pruning removes branches where they meet the closest lateral branch that is at least one-third the diameter of the original branch and that grows away from the electric line (if there is no lateral branch to prune to, however, the limb must be removed at the tree's trunk). That leaves a healthier tree with no stub to decay and prevents the growth of weak sprouts.

G.    Proper pruning may mean removing branches beyond the designated minimum fifty (50) feet of clearance for distribution lines or seventy five (75) feet for transmission lines. If the closest proper-size lateral branch is farther away than the minimum clearance, the limb will be removed to the proper joint for the health of the tree.  By directing growth away from electric lines, lateral pruning results in less future pruning, which reduces the visual impact and the cost of pruning. Controlling vegetation management results in cost savings for PES customers.

H.    In some instances, tree removal is the option that is the most beneficial to both PES and the property owner. Tree removal is the permanent solution. Repetitive trimming of fast-growing trees located directly under the lines is a costly, temporary fix. Many trees must be trimmed extensively in order to keep power lines clear. Unfortunately, such extensive trimming may cause the tree to develop internal decay and the tree may become a hazard not only to PES electric lines, but also to surrounding property.

I.    Anytime PES removes a hazard tree during the normal trimming cycle, a replacement certificate may be issued for a tree on the approved tree list.  The value of the tree replacement will be listed on Operating Policy 2-6.  In lieu of a tree replacement certificate, PES may do away with the stump of the removed tree.  This program is to encourage positive negotiation with the property owner and encourages selecting trees with size and growth characteristics that are not hazardous to PES electric lines.

J.    PES will clear undergrowth with a brush-cutting machine, tractor or mower.  Sprayed liquid herbicide will be used to control woody-stemmed plants in the right-of-way.  By using herbicides instead of clear cutting, PES will be able to target unwanted species of trees for removal while allowing “low growers” and native grasses to thrive. This creates a better balance between utility and the environment.

K.    For new services, it is the homeowner’s responsibility to prepare the right-of-way area as designated in sections A and B.  The right-of-way will be inspected and must be approved for compliance prior to construction.  PES will not be responsible for landscaping repairs for new construction.

L.    The property owner may establish the conditions for access to the right-of-way work area, but cannot unreasonably deny access to PES employees.

M.    PES will train and certify its employees on proper tree pruning, vegetation care and utility tree trimming safety following ANSI, ISA and other suitable standards.

To encourage community education and involvement in vegetation management, PES will participate in annual Arbor Day activities.  Furthermore, PES will donate ten cents ($0.10) per customer per year to establish new wooded areas in the Pulaski, Giles County area, as outlined in the Tree Line USA program.