Normal shedding vs a problem
Bark loss is not always a sign of trouble. Many trees shed bark as part of normal growth. As the trunk expands, the outer bark splits and flakes away, leaving fresh bark below. In other cases, bark falls off because the tissue under it has died.
| Clue | Often normal | Often a problem |
|---|---|---|
| Under the bark | Fresh, smooth bark, often a different color | Dry, dark, or bare wood |
| Canopy | Full and green | Thin, dying, or wilting |
| Pattern | Thin flakes or plates across the trunk | Large patches, one side, or a vertical strip |
| Species | Known to exfoliate | Not known for shedding |
| Extra signs | None | Oozing, fungi, insect holes |
Trees that naturally shed bark
Some commonly cited examples are sycamore, river birch, crape myrtle, shagbark hickory, bald cypress, and Chinese elm. The inner bark is sometimes a contrasting color, which is part of the appeal. Shedding can also help trees get rid of insects and growths such as lichens, though it is not the only reason it happens.
Eucalyptus (gum trees). Many eucalyptus species shed bark in strips or sheets, often in warmer months, and this is typically normal. Different species shed differently, and some keep rough bark, so check which species you have. Heavy shedding along with a thin canopy or dead branches is worth a closer look.
If your tree is a natural shedder, leave it alone. Pulling loose bark is not recommended and can injure living tissue.
Causes of problem bark loss
- Sunscald and frost cracks. Sudden temperature swings, especially on young or thin-barked trees, can kill bark on the sunny side and split the trunk.
- Drought or heat stress. Long dry spells can weaken a tree and cause bark to crack or lift.
- Mechanical injury. Lawn mowers, string trimmers, vehicles, ropes, and stakes left too tight can strip bark. Damage that circles the trunk is especially serious.
- Disease. Cankers and fungal infections can kill sections of bark, sometimes with sunken areas or oozing.
- Insects. Boring beetles and other pests can loosen bark, often leaving small holes or tunnels (galleries) under it. See large holes in a tree trunk.
- Lightning or fire. Strips of bark may be blown off.
- Animals. Deer rubbing, rodents, and woodpeckers can all damage bark.
- Root problems or overwatering. A stressed tree may decline and shed bark. See the signs of overwatering.
- A dead or dying tree. Bark often loosens in large sheets from dead wood. See how to tell if a tree is dead.
What an unhealthy trunk looks like
Signs that the trunk may be in trouble include:
- Bare, dry wood where bark was
- Bark loss that wraps most or all of the way around the trunk
- Cracks that run deeply or keep widening
- Dark, wet, or oozing patches
- Mushrooms or shelf fungi
- Tiny holes, sawdust-like frass, or tunnels under loose bark
- Dieback or thin foliage above the damaged area
What to check
- Identify the tree. Is it a species that normally sheds?
- Look under the loose bark. Fresh bark suggests shedding. Dead or bare wood suggests damage.
- Look at the canopy. A healthy crown is reassuring, and a declining one is not.
- Note the pattern and location. One side only, near the soil line, or after a particular event can point to a cause.
- Check for pests and fungi. Take clear photos for an arborist.
- Review recent events. Cold snaps, heat, construction, mowing damage, or changes in watering.
What to do (and what to avoid)
- Remove only loose, hanging bark if you must, and avoid cutting into healthy tissue.
- Protect the trunk from mowers and trimmers with mulch or a guard.
- Water properly in dry weather and avoid overwatering.
- Avoid wound paint or sealants, which are generally not recommended for tree wounds.
- Do not pull off bark from a tree that sheds naturally.
- Give a damaged tree time. Trees can form callus tissue over smaller wounds.
For a broader comparison of what healthy and struggling trees look like, see healthy vs unhealthy tree signs.
When to call an arborist
Contact a certified arborist if bark loss covers a large area or girdles the trunk, if the canopy is thinning, if you see fungi or insect holes, or if the tree leans or has big cracks. An arborist can identify the species and cause, and advise whether treatment or removal is sensible.