|
Many years ago, before I became an arborist, I had a mature maple in my front yard that worried me. The tree had some sort of problem, like a decay cavity or spiral split in the trunk. I can’t remember now. What I do remember is I thought the tree would certainly fall on the house, so I had it removed. It was the only tree on the property. At the time, I thought I did the right thing, but looking back I realized I made a big mistake that needlessly took out a tree that was doing good.
It is very common for people to be afraid of trees simply because they are large or are growing over the house. People see bad things happen with trees, and the natural response is to want to cut them down. People are all over the map in what they consider adequate safety. The perception of risk varies considerably.
What is the risk? It’s helpful to know the risk of being killed by a tree is really low, around 30 deaths per year in the U.S. That’s about the same odds as being struck and killed by lightning. Compare that with the car accidents which kill around 40,000 people per year, and swimming pools which kill 300-500 people per year.
Every tree poses some risk. There is no such thing as a zero-risk tree. So, does this mean every tree should be removed? Certainly not. Risk avoidance means not performing an activity that could carry risk. An example would be not buying a business so you don’t take on the legal liability that comes with it. Another would be not flying in order not to take the risk that the airplane might be hijacked. Avoidance may seem the answer to all risks, but avoiding risks also means losing out on the potential benefits that accepting the risk may have allowed. For example, trees around a home can increase its value up to 15 percent, according to the Arbor Day Foundation. Properly placed trees around buildings can also reduce air conditioning needs by up to 30 percent, and save up to 50 percent in energy used for heating, according to the USDA Forest Service. In addition, a single bur oak can host over 500 species of butterflies and moths.
After many years of being confronted with this dilemma, the International Society of Arboriculture developed Tree Risk Assessment Qualification (TRAQ). The amount of research on tree structure, health, and biology has grown in leaps and bounds over the last decade and the tree risk assessor must attend classroom training and pass an exam in order to be qualified. Using the TRAQ method, the tree risk assessor employs a systematic process to identify, analyze and evaluate tree risk.
The risk level is then communicated to the tree owner/manager. They must decide what level of risk they are comfortable with, whether it be low, moderate, high, or extreme. The final decision on mitigating risk is the tree owner’s and not ours. How we balance risk and benefits is really a management decision, not a tree assessment decision.
It is impossible to maintain trees free of risk; some level of risk must be accepted to experience the benefits that trees provide. In risk management we are trying to balance risks and benefits, and the TRAQ system gives us a good tool to retain trees, to demonstrate their value, and that the risk is worth the benefits.
To Find a TRAQ Arborist:
| 
