Some of the most serious threats to a tree are completely invisible from the yard. A tree can look full and healthy for years while a problem underground slowly tightens its grip. Two of the most common hidden killers we find in North Texas are buried root flares and girdling roots. Both are usually the result of well-meaning planting or mulching, and both can be corrected - if they are caught in time.
What the Root Flare Is and Why It Matters
At the base of a healthy tree, the trunk widens out where it meets the ground before spreading into the main roots. This flare, sometimes called the root collar, is meant to sit at or just above the soil line and be exposed to air. It is a structural and biological transition zone, and it is not built to be buried. When the flare is covered by soil or mulch, the bark stays constantly damp, which invites decay and sets the stage for roots to grow in the wrong direction.
How Trees End Up Buried Too Deep
Buried root flares almost always trace back to one of a few causes:
- Planted too deep. If a tree is set into the ground with its flare below grade, it starts life buried and never recovers on its own.
- Mulched too deep. Years of mulch piled against the trunk raise the effective soil line and swallow the flare.
- Fill or grading. Soil added over the root zone during landscaping or construction buries the base.
Once the flare is buried, the tree often responds by sending out roots into that shallow, oxygen-rich layer near the surface - and some of those roots begin to circle the trunk.
Girdling Roots: A Slow Strangulation
A girdling root is a root that grows around the trunk instead of away from it. As both the root and the trunk thicken over the years, the root presses harder and harder against the trunk, compressing the tissue just beneath the bark that carries water and food. In effect, the tree slowly strangles itself. The damage is gradual, which is exactly why it is so dangerous - by the time the symptoms show above ground, the problem has often been building for years.
Warning Signs to Watch For
Because the trouble is underground, you have to read the clues the tree gives you. Be suspicious if you notice:
- No visible root flare. The trunk goes straight into the ground like a telephone pole, with no widening at the base.
- Thinning, sparse canopy. Fewer leaves, smaller leaves, or early fall color, often worse on one side.
- Dieback in the upper branches that slowly works its way down.
- A trunk that does not flare, or even narrows, where it enters the soil - sometimes a sign of a root pressing against it.
- General decline in a tree that has no other obvious cause.
Any of these is a reason to look closer at the base of the tree rather than assuming the problem is up in the canopy.
The Fix: Air-Spade Root-Crown Excavation
The good news is that buried flares and girdling roots can often be corrected, and the tool of choice is an air spade. An air spade uses a powerful jet of compressed air to blow soil away from the base of the tree without cutting or damaging the roots the way a shovel would. This is called root-crown excavation.
The process lets an arborist safely uncover the root flare and inspect what is happening below the surface. Once the crown is exposed, the flare can be brought back to the proper level so it sits in the air where it belongs. Girdling roots can be identified and, where appropriate, carefully cut or removed before they choke the trunk. Because the air spade does not slice healthy roots, the tree keeps its support system while the harmful roots are addressed.
Timing matters. A tree caught early, before a girdling root has done severe damage, has a strong chance of recovering and living a full life. A tree left too long may be beyond saving. That is why an evaluation is worthwhile any time a tree is declining without an obvious reason.
If a tree on your property has no visible flare or a thinning canopy, do not wait for it to get worse. Treetop Tree Service offers free estimates and uses air-spade root-crown excavation to uncover and correct these hidden problems. Call our ISA Certified arborists at 817-992-6670 to have your trees checked.