Tree Risk Assessment

What is Tree Risk Assessment?

Resistograph results
Results of Resistograph1

The systematic process used to identify, analyze, and evaluate tree risk. Assessing risk requires the categorizing or to quantify both the likelihood of occurrence and the severity of the consequences.

Risk assessments will not justify the removal of healthy and safe trees, or the removal of an unwanted tree. Tree aesthetics are unrelated to tree risk assessment.

Mumby’s utilizes the ISA Tree Risk Assessment methodology and is qualified to use the BC Parks Wildlife Danger Tree Parks Module assessment method for BC Parks locations.

Image of large tree
Mature Trees can be retained!
Image of a fallen hollow tree
This tree had been topped. Decay penetrated the stem evidently causing it’s failure.
Using the Resistograph Image
Verna using the Resistograph1 to confirm the presence of decay in a large Douglas Fir tree.

The Resistograph machine precisely detects and measures decay and defects in trees and wooden structures. A fine steel drill is fed into the tree. As the drill enters the wood, the Resistograph records variable amounts of resistance encountered.


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