Section 2: Pruning Guidelines

Introduction

No matter what the reason for pruning, the tree’s health and appearance should always be considered. Recognized tree surgery practices provide for pruning with a minimum of harm to a tree’s health and appearance.
All right-of-way pruning practices by TxDOT employees, contractors, or utility companies with lines on state rights of way will conform to the guidelines of ANSI A300 Part 1-2001, Tree, Shrub and Other Woody Plant Maintenance – Standard Practices (Pruning). These guidelines represent the nationally used standards by the American National Standards Institute, Inc. The guidelines set forth in this chapter conform to these new standards.

Aesthetic Principles

When pruning, strive to:
Preserve the natural character of the tree and remove the minimum number of branches necessary to provide adequate clearance for safety or utility lines.
Trees which remain unsightly because of repeated pruning for clearance should be removed.
Proper pruning methods. (click in image to see full-size image)
Figure 4-3. Proper pruning methods.

Determining Amount of Clearance

When pruning for safety or clearance around utility lines, consider the rate of tree growth in determining the amount to be removed from a tree. A slow growing tree will require less clearance than a fast growing tree.
Maintain adequate clearance – not excessive clearance.
Acceptable pruning practices by utility companies. (click in image to see full-size image)
Figure 4-4. Acceptable pruning practices by utility companies.

Where to Cut and How to Remove a Limb

In removing a limb, the cut should be made at a fork where the remaining branch will be at least one third the diameter of the one removed. In most cases you can skip the first two steps and proceed to the last cut if the branch is less than two inches in diameter.
Use the following guidelines when cutting a limb two inches in diameter or larger:
  • Pruning tools must be sharp.
  • Undercut one-third of the way through the limb, eight to 12 inches from the main stem.
  • Remove limb four to six inches out from the first cut.
  • Remove stub with an even cut so that the branch bark collar is still protruding.
  • Paint the cut with approved tree wound paint.
    The three step method in proper limb pruning. (click in image to see full-size image)
    Figure 4-5. The three step method in proper limb pruning.
    Another illustration of proper limb pruning. (click in image to see full-size image)
    Figure 4-6. Another illustration of proper limb pruning.
    What happens when the guidelines are not followed. (click in image to see full-size image)
    Figure 4-7. What happens when the guidelines are not followed.

Disposal of Cuttings

All pruned wood and brush must be removed from the right of way and disposed of in accordance with the laws and regulations of the community, county and state.
Diseased branches (especially those infected with oak wilt) must be properly disposed of to prevent the further spread of the disease. (See Section 3, ,for more information.)