Illegal tree work in the right-of-way: bad for trees and people

Topped tree

When trees and people coexist, trees are sometimes mistreated, improperly pruned, or topped. When a tree is topped, its branches are all cut off at the same height.  Improper pruning encompasses making large, uneven cuts, taking off too much of the canopy or simply cutting branches in the wrong places.  The sad effect: the trees either die or respond by trying to quickly replace their leaf area, by  sending out new branches called watersprouts.  Watersprouts grow tall and dense, are poorly connected to the original trunk, and are prone to decay and breakage.  If the original intent was a smaller tree, poor pruning leads to the opposite: a bigger, denser, potentially dangerous canopy.

One might ask why such horrors are visited upon innocent trees.  Sometimes residents want their street trees to be smaller or fear that large trees are a safety risk.  Business owners might want greater visibility for their signs or awnings.  Unscrupulous workers calling themselves landscapers or arborists may offer to “take care of the trees” for a low price, when they have little or no knowledge of proper tree care.  Trees under power lines are a special case.  Sometimes a large portion of the canopy of a tree must be removed for clearance to prevent electrical fires or downed lines.  While utility pruning is unavoidable when large trees are unwisely planted under power lines, line clearance arborists should still make good cuts and prune as judiciously as possible.

Topped ornamental pear tree

If you are planning to prune your trees, there is a wealth of available information about proper pruning techniques.  SDOT Urban Forestry has produced a pruning guide, translated into 7 languages: Local non-profit PlantAmnesty offers pruning classes and workshops, and has an arborist referral service: . If you are hiring someone to work on your trees, choose a Certified Arborist.  Arborists certified by the International Society of Arboriculture must take a test to demonstrate their knowledge of tree care, including proper pruning techniques:  All trees in the right-of-way require permits prior to pruning branches over 3 inches in diameter.  Pruning according to arboricultural standards is a condition of the permit and SDOT urban forestry ensures that the permit holders are familiar with these standards.   Pruning permits in almost all cases are free, except where an extensive traffic disruption is involved. Link to permits information:  If you see someone pruning a street tree, you can ask to see their permit, and/or call (206) 684-TREE.

Improperly pruned oak tree