Should You Be Concerned by Exposed Tree Roots?

Tree Care Experts in San Francisco Bay Area Answer Questions About Exposed Tree Roots

As your trees mature, their root systems spread deep and wide in order to support their increasing height and mass. This is good because healthy roots mean strong, healthy trees that will stand tall and continue to share their benefits for many years. But when the most shallow of these roots become exposed, it can cause a variety of problems for you and your trees. Read on to discover everything you need to know about root exposure – and what you can do about it.

The Causes of Exposed Roots

A tree’s roots serve a few different purposes. Anchor and support roots run deep beneath the tree and are not likely to be exposed unless your tree is yanked out of the ground. Feeder roots, however, grow out more or less horizontally through the top eight to eighteen inches of soil. Their job is to absorb the moisture and oxygen needed to sustain the tree. Because they grow at such a shallow depth, these roots can become exposed for a number of reasons.
Root exposure is more common in older trees and in certain faster-growing species, such as willow and poplar shade trees. But any tree is susceptible in certain conditions. If root growth is hampered by some sort of obstruction, like a sidewalk, driveway, or building, the roots may be forced to the surface of the topsoil. The most common cause of exposed roots, however, is soil erosion – particularly in sloping areas. Overwatering, heavy rain, and runoff can wash away several inches of topsoil over time, leaving your roots uncovered and unprotected.

Effects and Dangers of Root Exposure

Apart from being a bit of an eyesore, exposed surface roots can lead to more serious trouble. A bare root is much more likely to be damaged by lawnmowers and other landscaping equipment, which can compromise its ability to absorb nutrients and water for the tree. Wounded roots are also more vulnerable to rot and disease.

Surface roots can even prove potentially hazardous to humans, as they can extend well beyond a tree’s drip line and are extremely easy to trip over. In some cases, above-ground roots can cause damage to surrounding structures such as storage sheds, garden beds, and even concrete slabs. If this is occurring, consult with a trusted tree service company in your area before taking any action.

What To Do (And What Not To Do) About Exposed Roots

A common misconception is that re-burying the exposed roots with fresh topsoil will solve the problem. It may work in the short term, especially if you overplant with grass or certain flower species, but the roots will eventually come back to the surface of the new soil. Not to mention that this method runs the risk of smothering your roots if too much soil is used.
The best solution is to cover the exposed roots with a layer of mulch. Pine straw or bark nuggets work well, but make sure your layer is no thicker than three or four inches, and leave a few inches of empty space around the base of the trunk, to avoid suffocating the tree.

In addition to insulating and providing protection for your roots, this bed of mulch will serve as a safe zone from lawnmowers and other potentially damaging tools. If erosion or obstructions persist in bringing your roots to the surface, contact a local professional arborist. They can implement preventative measures such as erosion barriers and advise you on safely pruning, or even – in extreme cases – removing trees with troublesome root exposure.

About Ned Patchett Tree Care & Consulting

Ned Patchett Tree Care & Consulting has been proudly serving San Carlos, California, and the San Francisco Bay Area, for years. They are a family-owned and operated company dedicated to safety, community, and excellent service.