Will Cutting Tree Roots Kill the Tree?

A tree’s roots are crucial to its overall health, as the roots act as anchors that secure the tree against harsh conditions. In some cases, cutting tree roots can kill the tree, but not always. Our guide takes you through the factors that affect whether trimming tree roots is harmful to your tree and how to prevent worst-case scenarios.

Can I Cut Tree Roots Without Killing My Tree?

Although it’s a risky move, cutting tree roots doesn’t always lead to a tree’s death. In most cases, you can cut up to 25% of your tree’s roots without causing permanent damage. Whether or not your tree survives depends on a number of variables, including what stage of growth your tree is in and how deep you cut the roots.

Factors That Impact Post-Cut Root Health

Let’s dig into the factors that affect whether snipping tree roots will negatively impact its health.

Severity of Cut

Minor cuts to feeder roots, which are responsible for absorbing water and nutrients, won’t significantly impact your tree. In fact, it can usually grow feeder roots back if needed. However, severe cuts to large, structural tree roots can compromise your tree’s stability and potentially lead to death. 

Tree Age and Health

Young, healthy trees are more likely to tolerate cuts to their roots without affecting their growth, as they usually grow back the roots they need and continue to thrive. Older trees that have been weakened by stress or tree disease are less likely to survive cuts to their roots as they are unable to grow new roots as easily. 

Timing of Cut 

Avoid cutting tree roots during spring or summer, which is when most trees are in active growth season. This period is the most stressful for trees and can limit their ability to recover from injury if you cut too deep into their root system. Consider cutting roots during dormant seasons like fall or winter when it’s less harmful to trees. 

How to Prevent Killing Trees When Cutting Roots

Although consulting your local arborist or tree stump removal professional is your best bet, there are other measures you can take when cutting tree roots to prevent damage to the tree. Try these tactics when severing roots:

• Avoid cutting large, structural roots and opt for trimming smaller roots 

• Steer clear of roots located within 3 to 5 times the trunk’s diameter 

• Make clean cuts with the proper tools for the type of roots you’re cutting 

• Refrain from cutting more than 25% of the tree’s roots at once 

• After trimming roots, water the tree and apply mulch around the base without touching the trunk 

• Call an arborist if you notice wilting leaves, yellowing or leaning in the tree