Tree Root Pruning

Root pruning can prevent your tree from dying when it comes time to transplant it. Knowing the ins and outs of root pruning will help you smoothly relocate your tree.

toddsmariettatreeservices.com gathered the following information about what root pruning is, why you should root prune, how to do it, and when it is necessary.

What Is Root Pruning

Root pruning is the practice of encouraging tree root growth (before transplanting) by severing existing roots at the tree’s drip line – the ground equivalent of the outer extremity of the tree’s crown.

This practice encourages new feeder root growth within the root ball to be transplanted along with its tree. Smaller root balls, with multiple feeder roots, help the tree acclimate faster to its new environment and soil.

Established trees have roots that reach out far beyond the tree’s drip line. These longer roots are used for anchoring and support. Most small feeder roots, which deliver water, food, and nutrients to the tree, will likely be found on these far-reaching roots at a greater distance from the tree.

It is nearly impossible, in most cases, to include all of these roots in the tree’s root ball. Yet, the more roots a tree has when it is transplanted, the faster and better it will adjust to its new location. Thus, root pruning is performed to encourage root growth before being transplanted.

Watch this video to see how root pruning can be accomplished without cutting roots.

Why Root Pruning Is Necessary

When a tree is unearthed for transplanting, the portion of the roots taken (the root ball) is only the circumference of the drip line, often less. Since the tree will be dependent on this root ball for most of its nutrients and water, it will need feeder roots within the root ball to continue sustaining itself during transplant shock. To encourage feeder root growth, closer to and within the drip line, the long anchor roots are pruned off.

How To Prune Roots

Root pruning is the severing of tree roots around the tree’s entire drip line. This can be accomplished by slicing down with a sharp spade. Consider the following steps:

1. Dig a trench around the outer edge of the tree’s drip line
2. Cut any roots you encounter with a sharp spade or shovel edge
3. Keep going until you have dug down far enough to sever the majority of the roots
4. Once you are satisfied with your work, fill in the trench with the soil you dug out
5. Replace the soil as it was, with the topsoil on top
6. Finish the pruning job by deep watering the tree

Note: The larger the tree’s root ball, the more feeder roots it will have for a successful transplant. However, larger root balls are increasingly heavy. Transplanting an established tree is not a job for one person, and you should consider calling a professional tree service for assistance.

When To Root Prune

Transplanting a tree isn’t a project that can be done on a whim without severely crippling or killing your tree. It’s going to take time, observe the following:

• If your tree will be moved in the fall, prune the tree’s roots in the spring; if the tree will be transplanted in the spring, prune the tree’s roots in early fall. This window of 6-7 months is enough time for new feeder root development.
• When transplant day arrives, dig out the trench and extract the root ball. Look closely and find that your previous pruning activities caused many new feeder roots to grow within the root ball (right where you need them to be).

Note: Root pruning, besides stressing your tree, leaves multiple open wounds that can fall victim to opportunistic pathogens, fungi, and pests.

Tip: Avoid root pruning activities if your other trees or plant life have recently been affected by disease or insect infestation. A professional tree service should be called in to evaluate and treat any disease or insect problems before starting a root pruning project.

More Reasons To Root Prune

Moving or transplanting a tree are not the only reasons to root prune. Root pruning also serves to:

1. Maintain the size of “dwarf” trees. When dwarf trees start to grow beyond their desired height or crown size, root pruning will shock the tree, causing it to divert its energy to root growth.
2. Encourage fruit trees to bloom. The tree thinks it is being attacked and sets a stress crop to propagate itself.
3. Slow the growth of potted plants that have outgrown their container. If you don’t want to move it to a larger container, root pruning and replanting (in the same container) with fresh soil should do the trick.
4. Remove surface roots that disrupt or invade your lawn (continuous damage to these roots may cause disease or infestation to weaken and eventually kill your tree).

For more on how to stop, remove, and kill invasive roots, visit toddsmariettatreeservices.com/tree-root-killing-removal-cutting/

Root Pruning

In this article, you discovered information about root pruning, why it should be done, how you can safely do it, and when it should be done.

Proper root pruning allows you to safely transplant an established tree without causing it to undergo severe shock.

Failure to root prune before moving an established tree leaves it without necessary feeder roots, starving it of water and nutrients, and can lead to its rapid decline and death.

Sources:
hort.ifas.ufl.edu/woody/root-prune-guidelines.shtml
hgic.clemson.edu/factsheet/transplanting-established-trees-shrubs/
extension.tennessee.edu/publications/Documents/sp571.pdf
extension.psu.edu/transplanting-or-moving-trees-and-shrubs-in-the-landscape