US TREE SERVICE



Trees provide significant benefits to our homes and cities, but when trees fall
and injure people or damage property, they are liabilities. Taking care of tree
hazards makes your property safer and prolongs the life of the tree.

Trees are an important part of our world. They offer a wide range of benefits to the
environment and provide tremendous beauty.

However, trees may be dangerous. Trees or parts of trees may fall and cause injury to
people or damage to property. We call trees in such situations hazardous, to signify the
risk involved with their presence. While every tree has the potential to fall, only a small
number actually hit something or someone.

It is an owner’s responsibility to provide for the safety of trees on his or her property.
This brochure provides some tips for identifying the common defects associated with
tree hazards. However, evaluating the seriousness of these defects is best done by a
professional arborist. Regular tree care will help identify hazardous trees and the risk
they present. Once the hazard is recognized, steps may be taken to reduce the
likelihood of the tree falling and injuring someone.

Hazardous Trees and Utility Lines

Trees that fall into utility lines have additional serious consequences. Not only can they
injure people or property near the line, but hitting a line may cause power outages,
surges, fires, and other damage. Downed lines still conducting electricity are especially
dangerous. A tree with a potential to fall into a utility line is a very serious situation.

Tree Hazard Checklist

Consider these questions:

  • Are there large dead branches in the tree?
  • Are there detached branches hanging in the tree?
  • Does the tree have cavities or rotten wood along the trunk or in major branches?
  • Are mushrooms present at the base of the tree?
  • Are there cracks or splits in the trunk or where branches are attached?
  • Have any branches fallen from the tree?
  • Have adjacent trees fallen over or died?
  • Has the trunk developed a strong lean?
  • Do many of the major branches arise from one point on the trunk?
  • Have the roots been broken off, injured, or damaged by lowering the soil level,
    installing pavement, repairing sidewalks, or digging trenches?
  • Has the site recently been changed by construction, raising the soil level, or
    installing lawns?
  • Have the leaves prematurely developed an unusual color or size?
  • Have trees in adjacent wooded areas been removed?
  • Has the tree been topped or otherwise heavily pruned?


Defects in Urban Trees
The following are defects or signs of possible defects in urban trees (see figure):

  1. regrowth from topping, line clearance, or other pruning
  2. electrical line adjacent to tree
  3. broken or partially attached branch
  4. open cavity in trunk or branch
  5. dead or dying branches
  6. branches arising from a single point on the trunk
  7. decay and rot present in old wounds
  8. recent change in grade or soil level, or other construction


Defects in Rural Trees
development
  1. previous tree failures in the local area
  2. tree leaning near a target
  3. forked trunk; branches and stems equal in size
  4. wet areas with shallow soil


Managing Tree Hazards

An arborist can help you manage the trees on your property and can provide
treatments that may help make your tree safer, reducing the risk associated with
hazardous trees. An arborist familiar with hazard tree evaluation may suggest one or
more of the following:

  • Remove the target. While a home or a nearby power line cannot be moved, it
    is possible to move picnic tables, cars, landscape features, or other possible
    targets to prevent them from being hit by a falling tree.
  • Prune the tree. Remove the defective branches of the tree. Because
    inappropriate pruning may weaken a tree, pruning work is best done by an ISA
    Certified Arborist.
  • Cable and brace the tree. Provide physical support for weak branches and
    stems to increase their strength and stability.
  • Provide routine care. Mature trees need routine care in the form of water,
    fertilizer (in some cases), mulch, and pruning as dictated by the season and
    their structure.
  • Remove the tree. Some hazardous trees are best removed. If possible, plant
    a new tree in an appropriate place as a replacement.

Recognizing and reducing tree hazards not only increases the safety of your property
and that of your neighbors but also improve the tree’s health and may increase its
longevity!
Recognizing Tree Hazards