moss on tree

Prevent Girdling Roots: How Root Collar Excavation Can Save Your Trees

The roots of your trees provide invaluable functions. They not only anchor your tree into the ground but they also help the tree to absorb water and nutrients from the soil. 

Without healthy tree roots, your tree will not thrive.

Unfortunately, girdling roots are a common problem that can lead to the decline or even death of your tree. Poor planting techniques are usually the culprit behind root girdling but it’s a problem that must be addressed.

In this article, we will talk about how to prevent girdling roots from killing your tree with a service called tree root collar excavation.

What are Girdling Roots?

A girdling root is a root that grows in a circular pattern around the trunk of the tree. Healthy roots are meant to grow deep into the soil. But when roots start to girdle, they wrap around the tree trunk and start to restrict the flow of water and nutrients.

It is estimated that a tree with girdling roots could die in 5 to 15 years if the problem is not addressed. During this time, the roots are slowly strangling your tree and cutting it off from key elements that it needs to survive.

tree care expert inspects tree with homeowner

This is not something that happens overnight. Homeowners will start to notice a tree’s decline, even if they don’t recognize what’s causing it.

Anytime that you notice a tree problem, it’s important to get a proper diagnosis from a tree care professional.

What Causes Girdling Roots?

Girdling roots occur when the tree’s root flare (or “root collar,” as these terms are interchangeable) is covered by dirt and mulch during planting. This part of the tree is sometimes referred to as its “heart,” as it’s an area where the trunk intersects with major lateral roots.

This is an essential part of the tree.

The root flare is comprised of living tissues that transport nutrients and water, gathered by roots, to the entire tree. If the root flare is damaged and cannot transport the nutrients, it will lead to poor growth of the leaves and branches of the tree. 

Tree care technician trims roots

This can be evidenced by poor leaf and canopy growth.

Root flare damage can also lead to problems with disease and pests as the tree weakens over time.

When trees are planted too deeply and the root flare is buried, the tree’s roots may respond by growing up, closer to the surface. But as this occurs, they tend to encircle the trunk. These girdling roots end up potentially causing more harm.

What is a Root Collar Excavation?

The best way to deal with this issue is tree root collar excavation. This service is what you would expect from its name. We are unburying the root flare (or “root collar”) with a careful excavation process.

“Careful” is the key word here. It’s quite important that the root collar is cautiously undug using small digging tools and a brush. The dirt should be removed carefully and slowly so as to avoid damaging the bark in any way. 

Since cautious excavation is so critical, a tool called an air spade is often used in the process. This is why you might have heard of tree root collar excavation being called “air spading.” 

Air spading simply means root collar excavation using an air spade.

This method of excavation involves using a hand-held soil excavation tool connected to a large air compressor to blow high-pressure air. It helps to remove or loosen the soil around the root collar without damaging the tree’s delicate root system, underground pipes, or hard surfaces.

tree care expert  pulls hose out of truck

It’s optimal to correct problems when a tree is young. 

In fact, if you’re looking at how to prevent girdling roots, this is possible if you unbury the root collar prior to girdling roots even happening. 

As we mentioned at the beginning, there are other reasons why burying the root collar is bad. It can lead to problems with decay, disease, and pests as this is a key part of the tree that was never meant to be covered.

But the older that a tree is and the longer that it’s been suffering from girdling roots the more damage might have been done. In a severe case, a tree with significant girdling might not be fixable. 

The good news is that trees are slow growing so you generally have time on your side. If you address this problem early enough, you should be able to preserve your tree’s health.

Finding a Professional Who Offers Tree Root Collar Excavation

If you have never heard of this service before, it’s because not all companies offer it. 

Tree root collar excavation requires extensive horticultural knowledge and experience. There is quite a bit of care and precision that goes into cautiously unburying the root collar.


Once unburied, there are also diagnostic skills that will be required to assess exactly what’s going on and how to deal with it.

That’s why it’s important to work with a tree service that employs Certified Arborists, They’ll be able to assess your tree roots and correct girdling roots if they are occurring. Amendments to the soil can also be made to boost tree health.

Preserving Tree Health with Tree Root Collar Excavation and Other Tree Services

Tree problems can be complicated so it’s always best to work with trained professionals who can help. 

Tree root collar excavation can be used to diagnose problems that might stem from a tree’s roots, including girdling roots. But it’s important that this service is performed by a professional with experience and training. 

At Seacoast Tree Care, serving Southern NH, Southern Maine, and Northeastern Massachusetts, we are committed to preserving the health and beauty of trees by properly diagnosing problems and implementing the best solutions. Tree root collar excavation is just one of various tree services that we offer. 

The end goal is always the same…doing what’s best for the health and longevity of your New England trees.

When you make a wise choice in tree services, you are taking an important step in preserving the value of your property’s trees.

Ready for healthier trees at your Southern NH, ME, or MA home? Request your consultation and get a free quote for tree services. We service properties in and around Stratham, NH, Kittery, ME, and Haverhill, MA. By making a wise choice, you’ll know your trees are in good hands.

Request a Consultation