Roots stretch far and wide to give our trees a stable foundation. But what happens if they grow a little further than we’d like?
One of our readers, Paul, recently asked, “How can I get rid of the roots from my tree that have grown into my front yard and are killing the grass?”
Dealing with roots can be tricky—an improper cut could affect the tree’s water flow or cause it to fall in a storm. That’s why it’s important to take a safe approach.
Read on to learn if you can prune above-ground tree roots, how many tree roots you can cut at once and how to safely prune tree roots at the best time.
Cutting Tree Roots Above Ground – Everything You Need to Know
If I cut a root, will the tree die?
It all depends on the size and location of the tree root.
As a guideline, avoid pruning roots more than 2 inches wide. Removing large tree roots can make the tree unstable or unhealthy later on. If large roots are removed, the tree may not be able to get enough nutrients and water. Also, don’t remove roots close or fused to the trunk since these are critical to the tree’s structure.
What’s the best time of year to cut tree roots?
If you choose to cut or remove tree roots, winter and early spring are the best time of year to do so.
How many tree roots can I cut?
Never remove more than 20 percent of above-ground tree roots at once. Then, wait two to three years to make sure your tree fully recovers. Only then can you safely consider cutting more tree roots.
How can I cut tree roots without killing the tree?
Again, if you cut tree roots, there is never a guarantee that it won’t hurt or eventually kill the tree. We only recommend removing tree roots when they are damaging or infringing on a nearby structure – not for aesthetic reasons.
For the best chance of your tree surviving, consult with your local arborist before removing tree roots. Or see if your arborist can prune the roots for you.
For DIY root cutting, use this step-by-step guide.
1.) Find the root posing an issue and trace it back to the base of your tree. If it turns out to be part of a large root, ask your arborist before pruning or cutting. For a smaller root, move to step 2.
2.) Measure the diameter of your tree. Wrap a measuring tape around the tree, four feet from the tree’s base. Then, divide that number by 3.14. Generally, you can safely prune roots that are 3-5 times the diameter away from your tree. So, if your tree has a diameter of 3 feet, only cut tree roots 9-15 feet away from the tree.
3.) Mark the area you’ll cut, and dig a hole all the way around the root until it is completely exposed.
4.) Use a root saw to prune the tree. Carefully pull the root up and away from the tree until it comes out. Be sure to refill the hole with soil from the same area afterward.
5.) Keep an eye on your tree for a few weeks after pruning. Signs of decline like yellow leaves or branch death call for an arborist’s immediate attention.