March of 2018 came in like a lion, roaring with sustained winds of 25 to 30 miles an hour. Predictably, trees fell on power lines causing fires that Virginia Department of Forestry personnel worked hard to put out. News outlets reported on the mayhem falling trees caused – power outages, traffic snarls, property destruction and, unfortunately, some fatalities. While the short-term focus in the emergency was on the death and destruction caused by several thousand falling trees, the long-term story is that hundreds of millions of trees did not fall.
Wood is strong and flexible; that is why humans have built with it for millennia. Not only have trees evolved to withstand strong winds, those winds make trees stronger. Just as lifting weights can trigger human muscle growth, swaying in the wind causes wood to grow. The alternating compression and tension on cells when a tree sways causes those cells to grow more wood. The result is the taper at the base of a tree.
Most of the trees that fell during the early March 2018 windstorm did so because they were already dead or dying. Most people can recognize a dead tree, at least during the growing season. However, most people cannot recognize a dying tree. These before and after pictures show a tree at Frying Pan Farm Park that failed during the windstorm. Last year it had leaves on it, but when it blew over, it revealed that its root system was rotten. Can you see the root rot in the standing tree? Look closely at the crown and notice the thinning of the leaves on the edges. To a trained eye, this is a sign of root problems. This is why trees, like pets and people, need to see their health care professionals regularly. Certified arborists are tree health care professionals.
The long-term story of the March windstorm is not that trees fell and caused mayhem. It is that strong healthy trees withstood the wind. And trees grow strong and healthy when they are properly cared for by professionals.
Author Jim McGlone is an Urban Forest Conservationist with the Virginia Department of Forestry. A version of this article ran on the VDOF blog at https://myvaforest.org/. Learn more about trees in Fairfax County in the blog, “Trees, Trees Everywhere…” at https://ourstoriesandperspectives.com/2018/03/14/trees-trees-everywhere-but-none-to-share/