If your tree doesn’t look as full or healthy as it once did, it’s natural to assume it just needs pruning, watering, or fertilization. But in many cases, the real problem isn’t happening above ground, it’s happening below the surface.
Across New England landscapes, one of the most common hidden causes of tree decline is girdling roots. Left unaddressed, they can slowly weaken—and eventually kill—an otherwise healthy tree.
The good news is that when caught early, a specialized service called root collar excavation can often uncover the issue and correct it before irreversible damage occurs.
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.
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.
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.
Signs Your Tree May Have Girdling Roots
Girdling roots don’t usually cause sudden, dramatic changes. Instead, the symptoms tend to appear gradually and can be mistaken for other issues.
Some of the most common signs include:
- A thinning or sparse canopy
- Smaller or underdeveloped leaves
- Early fall color or premature leaf drop
- Branch dieback, especially in the upper canopy
- A trunk that goes straight into the ground with no visible root flare
If you’re noticing several of these symptoms, it’s a strong indication that something below ground may be affecting your tree’s health. A professional evaluation can determine whether girdling roots are the cause.
What is a Root Collar Excavation (Air Spading)?
Root collar excavation is a specialized process used to expose the base of a tree and evaluate the health of its root system.
This is not simply digging around the tree. In most cases, professionals use a tool called an air spade, which uses compressed air to safely loosen and remove soil. This method allows arborists to uncover the root flare without damaging delicate roots, underground utilities, or nearby hardscapes.
Once the root collar is exposed, a trained arborist can:
- Identify girdling roots
- Carefully prune or manage problematic roots
- Evaluate overall root health
- Recommend additional treatments if needed
You may also hear this process referred to as air spading, but both terms describe the same precise and controlled approach.
Just as importantly, root collar excavation is not only a solution, it’s also a diagnostic tool. It allows professionals to see what’s actually happening below the surface, rather than making assumptions based on above-ground symptoms.
When Should You Consider Root Collar Excavation?
Many homeowners aren’t sure when this service is necessary. In general, it’s recommended when there are signs that a tree may be struggling due to root-related issues.
This might include:
- A buried or hidden root flare
- Unexplained decline in an otherwise healthy tree
- Visible roots circling the trunk
- Poor growth despite proper care
Timing is critical. Because trees decline slowly, there is often a window of opportunity to correct the issue. However, in more advanced cases—where girdling roots have been present for many years—the damage may already be too severe to fully reverse.
Why This Isn’t a DIY Job
It’s understandable to wonder whether you can simply dig around the base of your tree yourself. However, this is one area where improper work can do more harm than good.
The root collar is a sensitive part of the tree. Damaging the bark or removing the wrong roots can weaken the tree further or even accelerate its decline. There’s also the challenge of correctly diagnosing what you’re seeing once the soil is removed.
Root collar excavation requires:
- Precision tools like an air spade
- Knowledge of tree biology
- Experience identifying and correcting root defects
For these reasons, it’s best handled by trained professionals.
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.
Root Collar Excavation in Southern NH, Maine & Massachusetts
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.
