To the untrained eye, root sprouts and tree suckers may appear to be signs of nature doing what it is designed to do, but if you ask the experts, as we did recently in a conversation with our consulting arborist Norm Helie of The Growing Tree, it depends on the tree and where it is.
Sprouts and suckers occur naturally in almost all tree species and are part of the survival mechanism to help trees dominate a given area. According to Helie, more than 60 percent of forest regeneration in New England is from root suckers. In addition, trunk sprout growth helps trees naturally recover from catastrophic snow, wind, and ice events.
In the urban environment root suckers are more prolific than in nature and can be a response to certain stresses, such as insects or disease. Hearing Helie explain his observations and treatment regimens for the sprouts and suckers on trees in the Boston Common, Public Garden, and Commonwealth Avenue Mall, it sounds similar to how a dermatologist might describe treating growths found on a human body.
Root sprout growth takes energy from the tree and diverts it from the main trunk, which can then contribute to further decline. Proper removal involves removing as much of the cells that keep the sprout growing, called the meristematic tissue, as possible. The remaining tissue needs to be cauterized in order to inhibit new sprouts. Follow-up care is certainly needed to prevent new sprout growth, along with fertilization and disease control for overall health.
The next time you see a tree that appears to be struggling in our urban greenspaces, pause and see if sprouts and suckers are part of the problem. Helie says, "these trees always look like the best thing you can do is to cut them down but, in fact, these trees need attention and can do well with the right kind of care."
Learn more about the Friends tree care program. AfterPhotos: Norm Helie