Community Tree Risk Management: How to Detect Tree Defects and Conduct Tree Risk Assessments

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Community Tree Risk ManagementHow to Detect
Tree Defectsand Conduct Tree Risk Assessments

• Patrick Weicherding, Ph.D.
• Regional Extension Educator
• Natural Resources Environment
• Andover Regional Center

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Community Tree Risk Management

• Each year, city foresters and municipal managers
  face billions of dollars in property damage,
  personal injury, and even death resulting from a
  falling branch or tree. This public safety risk
  is predictable and preventable but requires a
  systematic approach to assess and treat defects
  in trees.

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Post Storm Surveys in Minnesota

• 84 of the damaged trees had pre-existing defects
  that were preventable and predictable.
• Most common pre-existing defects include
• - Decay
• - Weak branch unions
• - Codominant leaders
• - Stem girdling roots

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Tree Risk Management

• Tree risk management involves the process of
  inspecting and assessing trees for their
  potential to injure people or damage property.

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Tree Risk Management Inspections

• Tree risk management inspections include
• A systematic inspection of individual trees
• An assessment of tree defects
• Estimating the potential for failure based on
  accepted signs and symptoms of tree failure