Why would savvy business owners pay good money to top trees that beautify and shade parking lots and parking strips, when all it does is shorten the trees’ lives?
“I really don’t know why they do tree topping,” says Paula Dinius, urban horticulturist for WSU/Chelan County Extension. She and others were shocked to see so many topped trees around Wenatchee this spring — not a good sign for maintaining healthy trees.
If it’s worry about branches falling on customers or cars, topping trees just creates the problem they’re afraid of, since it weakens wood growth, she explains.
By cutting off the top of a tree, that cut will not close and seal out decay, so decay starts and continues down into the tree.
“Trees are genetically programmed to be a particular size regardless of what you do,” says Dinius. “When topped, the tree responds by sending out water sprouts. These are not normal branches but weak ones, with no supporting wood from the main branch.”
If topping trees is because they block signs, then perhaps some homework is needed up front to either select a smaller tree that will not cover the sign, or else buy a large tree that branches out above the sign.
Dinius advises businesses or individuals hiring an arborist to check that they know how to trim trees properly, and not just go for the lowest bid.
For trees that have already been topped, she says they can be kept smaller by recutting about every three years, but this significantly decreases the tree’s life span as well as increases maintenance costs.
Dinius suggests several resources to help you learn more about proper tree care. Websites include:
• InterNational Society of Arborculturists (ISA) Pruning Mature Trees
• Pruning Young Trees
• National Arbor Day Foundation
You just missed Dinius’ annual spring tree management seminar, but watch for it next year in May. If you have questions regarding tree pruning or other tree care topics, you can contact WSU Chelan County Master Gardeners at email@example.com or Dinius at firstname.lastname@example.org.
It’s certainly less costly to select the right tree for a particular location and allow it to grow naturally, without all the pruning hassle. And be able to enjoy its beauty for years to come.
A WSU Master Gardeners of Chelan County column appears weekly in the At Home section. Mary Fran McClure is one of three columnists featured.