Risk Assessment Basics

Today I would like to speak a little about tree assessment and risk management. There are three broad factors to consider when trying to give an assessment of tree risk.

What is the potential for tree failure.

Failure of the tree is the likelihood that the entire tree, or part of the tree will break or fall within a given time period. The arborist would consider the species, growth habits of that species, defects or decay of the tree, the quality of the branch attachments, condition of the root system, the lean of the tree and the history of the tree and site.

What kind of environment is the tree in that may contribute to the failure.

Most tree failures are the result of storm damage. Exposure to high winds, snow and ice, lightning, soil conditions, and slope need to be considered. Also, grade changes around the tree, removal of adjacent trees that previously served as a wind buffer, root loss or root pruning, failure of nearby trees caused by root disease.

What would be damaged and/or injured in the event of the tree failing.

This would be people and/or property that could be damaged if the tree or part of the tree failed.

I think we learned enough for the day. The moral of story then might be to take good care of your trees to help avoid any risk of damage or injury. Or if I were a Chinese fortune cookie, “We cannot direct the wind, but we can adjust the sails.”