Why Is Tree Bark Peeling

If you’ve noticed strips of bark lying around your tree, you might be wondering, why is tree bark peeling? In many cases, this is a completely normal part of a tree’s life cycle. It’s a natural shedding process that helps the tree grow and stay healthy.

Think of bark like the skin of a tree. Just as we shed old skin cells, trees need to shed old bark to make room for new growth underneath. This process allows the tree to expand in girth and protects it from pests and disease. Before you worry, let’s look at how this works and when it’s a sign of trouble.

This natural shedding is a sign of a healthy, growing tree. The technical layer responsible is called the phloem (which transports food) and the cork cambium. As the tree adds new layers of wood from the inside, the outer bark must stretch. Since it can’t stretch infinitely, it cracks and peels away.

This shedding serves several critical purposes. It gets rid of old, inefficient tissue that might harbor lichens or moss. It can also help dislodge insects trying to burrow in. For some species, it’s a key part of their identity and survival strategy.

Tree Species That Naturally Peel

Some trees are famous for their exfoliating bark. If you have one of these, peeling is almost always normal.

Sycamore and London Plane: These trees shed in large, irregular patches, revealing a beautiful mosaic of creamy white, green, and tan underneath.
Paperbark Maple: As it’s name suggests, it has thin, papery sheets of cinnamon-colored bark that curl and peel.
River Birch: Valued for it’s shaggy, curling strips of pinkish, tan, and white bark.
Eucalyptus: Many types shed long ribbons or flakes of bark, often in stunning colors.
Crape Myrtle: The smooth, mottled bark sheds in thin flakes to reveal new patterns beneath.
Madrone (Arbutus): Sheds in thin sheets, showing a satiny, reddish new surface.

How to Tell if Peeling is Healthy

Healthy peeling has a distinct look. The bark underneath, called the inner bark or cambium, should appear fresh and smooth, often a different color. The peeling pattern is consistent with the tree’s known character. There are no signs of oozing sap, deep cracks into the wood, or insect holes under the shed pieces. The tree’s canopy will be full of leaves in season, showing no major dieback.

When Peeling Bark Signals a Problem

Not all bark loss is good. Sometimes, it’s a cry for help. Here’s what to watch for:

Sudden, Extensive Peeling: Large sections falling off a tree that doesn’t normally peel.
Dark Discoloration Underneath: Black, brown, or moist areas under the peeling bark.
Insect Activity: Sawdust-like frass, numerous holes (like shotgun blasts from borers), or visible insects under the bark.
Fungal Growth: Mushrooms or fungal conks growing on the trunk where bark is missing.
Dieback in the Crown: If the top branches are losing leaves or dying, bark peeling on the trunk could be related.

Common Causes of Problematic Bark Loss

If the peeling doesn’t look natural, one of these issues could be the culprit.

Environmental Stress

Extreme weather is a common trigger. A sudden, deep freeze after a warm fall can cause the bark to split and peel. Sunscald, especially on young trees or the south-west side of thin-barked trees, kills the living tissue under the bark, causing it to slough off. Severe drought can also cause bark to crack and separate.

Insect Infestations

Bark beetles and borers are major pests. They tunnel under the bark, disrupting the flow of nutrients and essentially girdling the tree. Their activity often causes the bark to fall off in patches, revealing intricate tunnel patterns (galleries) underneath. Look for tiny holes and sawdust.

Fungal or Bacterial Diseases

Diseases like canker fungi attack a tree’s bark. They cause localized dead areas that sink and crack, eventually causing the bark to fall away. Bacterial diseases like fire blight can also cause bark to appear water-soaked and peel. These often require professional diagnosis.

Physical Damage

Lawnmowers, string trimmers, and even animals rubbing against the trunk can wound the bark. This damage creates an entry point for pests and disease and can kill a vertical strip of bark, causing it to peel away from the healthy parts over time.

What to Do If You’re Concerned

Follow these steps to assess the situation and take action.

Identify the Tree: First, figure out what species you have. Is it known for peeling bark?
Inspect the Pattern: Look at the areas where bark is gone. Is the exposed wood healthy-looking, or is it discolored and damaged?
Check the Canopy: Are the leaves sparse, discolored, or smaller than usual? This is a vital clue.
Look for Pests & Fungi: Examine the trunk and fallen bark for holes, sawdust, or mushrooms.
Consult an Expert: When in doubt, contact a certified arborist. They can provide a definitive diagnosis and treatment plan. It’s worth the investment to save a mature tree.

How to Support a Tree with Healthy Peeling

For trees that shed naturally, your job is simple: support their overall health. Provide consistent water during dry periods, especially for young trees. Apply a layer of organic mulch around the base (but not touching the trunk) to retain moisture and regulate soil temperature. Avoid using weed trimmers near the trunk to prevent accidental damage. And never try to pull off peeling bark—let the tree shed it on it’s own schedule.

FAQ: Your Bark Peeling Questions Answered

Q: Is it bad to peel bark off a tree yourself?
A: Yes, never peel bark off a tree. You can damage the sensitive cambium layer underneath, which is essential for transporting water and nutrients. This can wound the tree, making it susceptible to disease and pests.

Q: Can a tree survive if its bark is peeling all around the trunk?
A> It depends on the cause and extent. If the inner cambium layer is still intact and functional around the entire circumference, the tree may recover. However, if a band of bark is missing all the way around (girdling), it will likely die, as nutrients cannot flow. This is a serious condition.

Q: Why is my pine tree losing bark?
A: Pines do not naturally shed bark like sycamores do. Bark loss on a pine is often a sign of stress, such as from pine bark beetles, fungal infection, or severe physical damage. Inspection by an arborist is recommended.

Q: Does peeling bark mean my tree is dying?
A: Not necessarily. For many species, it’s a sign of vigorous growth. The key is to look at the whole tree. If the peeling is part of the tree’s normal appearance and the canopy is healthy, it’s likely fine. If peeling is accompanied by dead branches, leaf loss, or signs of pests, it could be in decline.

Q: Should I paint or seal the area where bark peeled off?
A: No, this is an outdated practice. Tree wound sealants can actually trap moisture and promote decay. Trees have their own compartmentalization process to seal wounds. Your best bet is to keep the tree healthy and let it heal on its own, unless a specific disease treatment is advised by a pro.

Understanding why is tree bark peeling gives you the power to be a better gardener. You can appreciate the beautiful, natural process in some trees and act quickly to help others in distress. By observing your trees closely and responding to their needs, you ensure they remain healthy and beautiful parts of your landscape for years to come.