Q. In our condominium complex we have several English oak trees. We had an arborist prune those plus another 40 trees of different species. The English Oaks are getting to be approximately 30 plus ft. tall. I hear that they may grow to 40 to 70 ft. tall. The arborist told us that they should not be topped. Some of the residents are complaining that they are afraid that they will become a hazard as they may blow down. What do you suggest we do? Thank you, Donald Berglund – Lakewood, WA
A. I suggest you follow your certified arborist’s recommendations. Topping is an outdated technique for attempting to reduce the size of trees. Just like most scientific based practical applications there have been many changes over the past few decades in arboriculture. Research has shown that topping or “heading back” trees creates more problems than it solves. It can even make a tree more hazardous. The International Society of Arboriculture (ISA) credentializes certified arborist (through local chapters). These individuals must also maintain continuing education credits, which keep them up to date on the latest science and techniques of their field. If you are hiring a certified arborist to look after the health of your trees then you are reducing the hazard potential of these trees. Tree height is more of an indication of how much damage a hazard tree can cause, not necessarily that they will be a hazard. Any factor that diminishes the health of the trees will contribute to that trees hazard potential. For more information on why topping is bad you can see an article developed by the ISA called “Why Topping Hurts Trees”, http://www.treesaregood.com/treecare/hazards.aspx. There are some other great articles on this website for the homeowner as well that explain hazard trees.