Roanoke Tree Removal is a local referral service: we pass your request to an independent, local tree crew. We are not a government office, plant pathologist or insurer, and this page is general information, not a diagnosis.
What stem girdling roots do
Purdue Extension's stem-girdling-roots Q&A says roots wrapped around the trunk or lower stem can be very troublesome for health and safety. They can compress the stem enough to raise windthrow risk and reduce water and nutrition flow, leading to slow decline and eventual death if untreated. Maples are called out as a species where the problem is especially common.
Because the damage builds slowly, homeowners often notice the mulch pile or a flat trunk line years after planting. Catching circling roots while the tree is still young is far easier than dealing with an embedded root on a large maple next to a driveway or house.
How they form
Circling roots often start in a nursery container or a planting hole that is too small, so roots turn instead of growing outward. Compacted soil or hard edges can send roots back toward the stem. Purdue's mulching guidance adds another homeowner cause: volcano mulching, where mulch is piled against the trunk. That moisture and darkness at the stem can promote unnecessary root growth and stem girdling roots that cut off nutrient supply between the roots and the crown.
Planting depth and clearance from the house also matter for long-term root room; see tree too close to the house.
Mulch volcanoes versus a proper ring
Purdue's June 2025 mulching note says to add a 2 to 3 inch layer sloping away from the tree, with at least a 3 to 5 foot radius around the stem, and about a 1 to 2 inch gap between the stem and the start of the mulch. No volcano mulching. If a tree already has a volcano, dig out the excess, expose the root flare, and recreate that gap. That step costs little and is the first fix before anyone cuts a major root.
Signs worth a closer look
| What you notice | Why it may matter | First step |
|---|---|---|
| Flat or reverse trunk flare; stem looks straight into the soil | Flare may be buried or compressed by circling roots | Pull mulch and soil back to find the flare |
| Roots visible wrapping the stem | Classic stem girdling root pattern | Photo it; call an arborist before cutting large roots |
| Thinning crown, early fall color, dieback on one side | Possible reduced flow past a compressed stem | Rule out pests and soil issues too |
| Tree that rocks or leans after storms | Stability may already be compromised | '''+a('Arborist risk assessment','/services/arborist-risk-assessment')+''' before root work |
| Mulch piled against the trunk | Volcano mulch linked to stem girdling roots (Purdue) | Rake mulch back to a flat ring with a stem gap |
When cutting helps, and when it does not
Purdue says that on a small or juvenile tree, if circling roots are less than one-third the trunk diameter and can be removed without damaging the trunk, careful cutting and removal can stop the circling habit. Some arborists remove larger girdling roots with good response, but Purdue warns there are no guarantees. Roots that have embedded into the trunk or stem should be left alone. Any root removal can reduce stability and health, so Purdue recommends an International Society of Arboriculture Certified Arborist for the work.
What not to DIY on a large tree
Do not saw into the trunk to chase an embedded root. Do not remove several large roots on one visit without a plan for stability. Do not dig along a foundation or utility corridor without calling Virginia 811 first. If the tree is already a lean or decay hazard, root surgery is the wrong first tool; see remove or trim? and hazard tree removal.
Prevention at planting and after
- Inspect the root ball.Look for circling roots before the tree goes in the ground.
- Dig a wide hole.Give roots room to grow outward, not around a tight wall of soil.
- Set the flare at grade.Do not bury the stem; backfill only to the flare.
- Mulch as a flat doughnut.2 to 3 inches deep, 3 to 5 feet out, 1 to 2 inches off the stem (Purdue).
- Recheck after a few seasons.Pull mulch back and look for new circling roots while the tree is young.
Species and age change the odds
Purdue flags maples as especially prone to stem girdling roots, but other landscape trees can develop the same wrap when planted from circling containers or buried too deep. Young trees are the easiest to correct because roots are smaller and less embedded. On a mature tree with a flat flare and a history of thin crowns, expect the arborist to talk about risk and stability, not only about cutting one root. Start with arborist risk assessment before anyone rents a saw.
Aftercare once a root is cut
If an arborist removes a non-embedded girdling root, ask how the wound and soil will be left. Purdue's mulching guidance still applies afterward: keep a flat 2 to 3 inch ring, leave the 1 to 2 inch stem gap, and do not rebuild a volcano while the tree recovers. Watch for lean or new dieback through the next growing season. If multiple large roots need work, Purdue notes it may be wiser to stage removals across seasons so the tree can adjust.
Have girdling roots checked in the Roanoke Valley
Call (540) 904-1819 or use the form, and we will pass your request to an independent local crew. Tell us the species if you know it, trunk diameter, whether mulch is piled against the stem, and if the tree leans toward a target. ISA's Find an Arborist directory is another way to locate credentialed help.
Sources
- Purdue Extension FNR, Are tree roots wrapped around a tree trunk a concern? (stem girdling roots) (Checked Oct 13, 2026)
- Purdue Extension FNR / Purdue Landscape Report, Simple Steps to Care for Your Tree: Mulching (June 6, 2025) (Checked Oct 13, 2026)
- International Society of Arboriculture, Find an Arborist (Checked Oct 13, 2026)
- Virginia 811, Call Before You Dig (Checked Oct 13, 2026)
Common questions
What are girdling roots?
Stem girdling roots wrap the lower trunk and can compress the stem. Purdue Extension says they reduce water and nutrient flow and can raise the risk of windthrow, especially on maples.
What causes stem girdling roots?
Circling nursery roots, tight planting holes, compacted soil, and volcano mulching against the trunk are common causes. Purdue links excess mulch against the stem to stem girdling roots.
How do I fix a mulch volcano?
Purdue says to dig out the excess, expose the root flare, and leave about a 1 to 2 inch gap between the stem and a 2 to 3 inch mulch ring that extends 3 to 5 feet out.
Can I cut girdling roots myself?
On small trees, Purdue says circling roots less than one-third the trunk diameter may be carefully removed if the trunk is not damaged. Embedded roots should be left alone. Hire an ISA Certified Arborist for larger work.
Should embedded girdling roots be removed?
Purdue says roots embedded in the trunk or stem should be left alone. There are no guarantees with that risky process.
Do girdling roots mean the tree must come down?
Not always. Young trees with shallow circling roots can often be corrected. Trees with severe compression, lean or target risk need an arborist risk assessment before anyone decides on removal.