Peeling Bark On Lilacs: Reasons For Lilac Bark Coming Off Tree

Peeling Bark On Lilacs: Reasons For Lilac Bark Coming Off Tree

By: Jackie Carroll

Lilac trees make beautiful additions to the home landscape, with flowers much like those on lilac shrubs but without the fragrance. These medium-sized trees are appropriate for most home landscapes and they make well-behaved street trees. Environmental factors are usually to blame when a lilac is shedding tree bark.

Causes for Lilac Bark Coming Off

In most cases, the damage from lilac bark shedding isn’t serious. Young trees are more susceptible than older ones, but you may see the problem in trees of any age. Here are the most common causes of splitting or shedding bark:

Rapid freeze and thaw cycles sometimes cause splitting and peeling bark on lilacs. This often happens at the site of a previous injury.

Excessive late fall growth is a common culprit. This occurs with high temperatures or humidity in late fall. You will also see late fall growth spurts when you use too much nitrogen fertilizer late in the season.

Dry weather followed by wet weather causes fluctuating growth, resulting in splits in the bark. Watering the tree during dry spells can help prevent this condition.

Sunscald can cause unsightly bark damage. It may be the result of heavy pruning that allows harsh winter sunlight to filter through the canopy.

Other Reasons Why Lilac is Shedding Tree Bark

Peeling bark on lilacs doesn’t always indicate a problem. Some cultivars, such as ‘Copper Curls’ lilac, have ornamental peeling and curling bark. The irregular, bright orange curls are perfectly normal and part of what makes the tree interesting in winter.

Probably the most serious problem to look for when lilac bark is coming off is the lilac borer moth. This inch long (2.5 cm.) moth looks like a wasp. Its larva bores into the base of branches, causing severe damage. The bark becomes swollen and eventually cracks and breaks away. Mild infestations can be treated with insecticide, but in severe cases, the tree should be removed.

Now that you know what causes bark to peel on lilac trees, you’re probably wondering how to treat the problem. Recent studies show that wound paints and sealers don’t help the tree heal faster and may even slow the natural healing process. The best solution is to let the wound callous over naturally. While the wound heals, watch for insects that may infest the exposed wood and spread diseases. The injury may leave a scar, but natural scars often add character to the overall appearance of the tree.

This article was last updated on

Read more about Lilac Bushes

Lilac Tree Losing Bark?

We moved into our new home last October. We noticed that the bark on the lilac tree is coming off. A lot of the branches have died. I am not sure if the previous owner chopped it. I tried my best to cut all the dry branches and it seems like it's OK. It does have some flowers on it. My question to you is why is the bark falling off the tree. And I notice where the lilac tree is there is a bit of moss on the ground and a bit on the tree. Could this be the cause of it? Is there something I could put to help it?

Add your voice! Click below to answer. ThriftyFun is powered by your wisdom!

Try moving it in a different location away from where the moss is growing, the moss is taking all the nutrients away from tree. After you dig up the tree get as much of the dirt out of the roots that you can and then use some garden soil, and water for 7 days straight till it takes root. After about 7 months add some fertilizer like bone meal or blood meal. Good luck! Lilacs are my favorite flower and I wish they bloomed all summer long but they don't.

Add your voice! Click below to answer. ThriftyFun is powered by your wisdom!

Disinfect a knife with a solution of 10-percent bleach and 90-percent water and make a slender slice into the bark. If the wood is soft and stained a dark brown the tree may have foot rot. This is a fungal disease that begins at the bud union and can girdle the tree.

Examine the under side of a piece of bark or the cracked margins with a magnifying glass. If you see small black, red, orange or yellow fruiting bodies the plant has any one of a number of fungal diseases. You can narrow it down by looking for the color of the fungus.

  • Flick off some of the bark where it is disfigured with a knife.
  • The absence of patchiness under the bark may indicate Psorosis, which comes from may viruses and causes scaly bark.

5 Reasons Bark Is Falling Off Of Your Trees

When you think about bark on trees, you have to compare it to the skin on our faces. They do very similar things: protect what is inside, act as a covering, and tell many different stories. When you look at the skin on someone’s face, for example, you can tell a lot about the person and the life that they have lived. Even more importantly, you can tell a lot about how they feel. With a tree’s bark, you can do something similar in that you can tell if there might be something wrong with the tree or if it isn’t feeling its best.

While it might not look so good, peeling bark can actually help you to better understand your tree and get it the help that it needs before it is too late. So why are your trees peeling? Here are just a few common reasons why:

5. Thin bark

  • Common in some trees
  • Happens naturally in warmer climates
  • Can be a seasonal change

As humans age, our skin gets thinner and you can see the effects it has on our faces: wrinkles, cracks, and discoloration. If your tree has thin bark, it is more likely to peel than a tree that doesn’t have thin bark. Sometimes, it does so naturally when the time is right – like during the spring months or in the middle of fall.

When this topic was investigated by NYC Parks, they found that some shedding may have to do with the photosynthesis process – or the process in which plants obtain nutrients from sunlight. The cracks allow more sunlight to reach the delicate inner systems of the tree.

You can do a quick online search to see if your trees naturally peel or if it is something that you need to worry about.

4. Environmental Causes

Of course, environmental causes are another big reason for the bark of your tree to peel. Everything from an early frost to draught in the summer months can cause the bark of a tree to peel.

According to Gardening Know How, “Peeling tree bark is sometimes due to environmental factors. When peeling bark on trees is limited to the south or southwest side of the tree and bare wood is exposed, the problem may be sunscald [sic] or frost damage. This type of shedding affects the health and lifespan of the tree, and wider areas of exposed wood make it more likely that the tree will die.”

If a tree was already peeling and then it happens again – which happens quite frequently in the winter months when sun scalding is prominent – the process can be repeated and you will have several layers of peeling bark.

There are ways to prevent this, and it is something that tree owners need to look into – especially if you have sensitive or exotic trees.

3. Insect Infestation

  • Boring insects cause peeling everywhere
  • Ants cause peeling toward the bottom
  • Look around holes

Bark that starts peeling toward the bottom is often a sign that an ant infestation has caused the peeling – either because they introduced a fungus or a disease or because they are overwhelming the tree. Unfortunately, this peeling often makes the problem worse.

These holes invite more pests and more diseases, which can eventually disrupt the vascular system and slowly start to kill the tree. If you notice holes in your tree that have peeling bark, this is likely the reason why your tree doesn’t look so healthy.

Common insects can cause the problem too, like bees and ants so you need to be vigilant in checking. It isn’t unusual for this to happen on trees that were already sick or if the tree just recently got over an illness, according to Texas A&M.

2. The tree is exfoliating itself

Another reason that your tree may be peeling? Call it tree puberty. Trees exfoliate themselves just like we do with our skin, especially when there is something on the bark that the tree doesn’t like – such as weed killers and pesticides.

Per Home Guides, “A tree grows by forming a new layer of fibrous tissues deep within its core. As it grows from the inside, its outer layers expand, and it sheds its old bark to make way for the new. The bark on a young tree is generally smooth and flexible and can withstand the inner growth without much effect. Old bark, however, is dry and has lost much of its elasticity, causing it to crack and split as the tree grows.”

This is something that will vary by tree and location – sometimes sunlight can exasperate the situation. Some trees won’t have a problem at all and never have to exfoliate, even if they are the same type of tree. Note that the need to exfoliate can be brought on by disease, drought, or insect damage.

1. Tree is Dying

If you have peeling that is all over the tree or just goes extremely deep, the unfortunate reality is that the worst may have happened: your tree is either about to die or has already died. For many trees, the peeling bark is a cry for help, according to the University of Arkansas Division of Agriculture. If you catch it in time, you will be able to save the tree with professional intervention.

Whatever you do, do not overlook peeling skin on your trees. This will only cause whatever the underlying problem is to get worse or open your tree up to other issues. If you see quite a bit of bark peeling or falling off of your trees, it is time to do something.

At AK Timber Services, our main concern is that your trees are as healthy as possible, which means that we do have to do some investigation as to why your trees are peeling in the first place – and that can be extremely difficult and take some time. If you are worried about the health of your trees or fear the worst, it is highly important to give us a call as soon as you can. In many cases, there is no time to waste.

Give us a call today at (360) 635-1076 and our professionals will pay you a visit to investigate your trees and see how we can help you.

Lilac Troubles: White Mold & Bark Eating 'Bees'

Q. I've been noticing white stuff on the trunk of my lilac bush. Is it harmful? If so, what can I do? The lilac gets a lot of sun—from around 1:30 pm until sunset.

A. Sorry Linda, but that is NOT a lot of sun, and it's the way wrong kind of sun for a lilac. Like roses, tomatoes and other disease-prone plants, lilacs need morning sun to dry overnight dew and dampness off their leaves. If other plants are blocking that early sun, see if you can prune or remove them. Otherwise, do everything you can to increase airflow to the area.

This includes pruning the lilac immediately after flowering every Spring to open up the center and increase the internal airflow. Remove some entire older branches down at ground level first, then take out some of the younger branches that are crossing or otherwise restricting airflow. Remove all the spent flower heads promptly as well. Do these chores immediately after the flowers have faded and it will improve the following year's flowering as well as help keep the white stuff at bay.

Q. I have a "patch" of lilacs, (i.e., one big bush with multiple trunks). Every year a white flaky substance appears on the trunks and branches, as well as a white coating on many of the leaves. A lot of the branches covered with the dreaded white stuff are dead the next spring. What can I do?

A. I just can't exaggerate what notorious drama queens these plants are about airflow. My lilac—a very hardy disease resistant variety—is growing near a bunch of ancient, inherited ferns, and anytime the ferns try to grow anywhere near the outskirts of the lilac, the wussy plant gets a white moldy coating on the trunk. When this happens (once every couple of years), I rip the offending ferns out right away, apologize to Her Majesty, and—believe it or not—just wipe the white stuff off with a damp cloth. Occasionally, I've come home from a summer vacation and 'Christmas in July' has spread to a few leaves as well, so they get pulled off and trashed.

It can't be stressed enough: Lilacs need airflow! Don't plant them in a crowded area and make sure their area stays nice and clear all around. If the white stuff still shows up, remove and destroy any affected leaves immediately and wipe the white stuff off the trunk and branches. If you want to be fancy, mix some baking soda into the water you use for your washrag. Or even better, use compost tea for the wiping down that'll remove the gunk and leave a disease-fighting residue behind.

In addition, never feed a lilac chemical fertilizer or use a wood, bark or root mulch underneath it both breed disease like mad. As with roses, remove any old mulch in the spring and replace it with an inch or two of fresh, high-quality yard-waste compost. That will feed the plant for the season and prevent disease spores from incubating down there. And if the season is wet, cloudy and damp, remove that mulch and replace it with fresh compost mid-season.

Q. I thought I had an infestation of bees feasting on my lilac's branches, but now I'm not sure they're aggressive, golden-yellow, about an inch-and-a-quarter long and have wasp-like wings. What are they and how do I get rid of them?

---Ed in Clarksville, Maryland

We have wasp-like bees eating the bark on one of our lilacs. Nothing I've tried will keep them away. Help!

These two Washington, DC area gardeners emailed me within a few days of each other in mid-September a surprising time of year to have this kind of problem, as wasps and hornets are pretty much done for the season at that point.

That's right—the culprit is wasps, not bees. Carpenter bees do famously hollow out breeding galleries in soft woods like cedar, but they don't strip the bark off of trees. Paper wasps and hornets (themselves a type of wasp), however, DO perform this kind of mischief so that they can use the bark as building material for their papery nests. Some sources feel they also feed on the sap that flows as a result of their peeling.

Because they ARE wasps and NOT bees, they are aggressive and WILL sting if confronted, so be careful. And although these insects are a nuisance when they strip bark, they are also very useful predators that eat lots of caterpillars and other garden pests having a hornet's nest near a garden has been shown to reduce the number of cabbageworms by more than half! So try and deter rather than kill them. Spray the bark at night with an organic repellant, like neem or one of the garlic oil products sold for outdoor mosquito control. Or wrap it with strips of row cover, sheer curtain, or other gauzy material.

Heck, wrap the whole plant in row cover if you can do it. That'll keep the hornets away while still letting light and air reach the plant.

Don't seal or otherwise try and repair any of their damage to the bark let the plant take care of that naturally. And finally, don't worry about this becoming a regular problem. No one knows why these insects pick specific targets in certain years, but each colony only lives for one year, and successive generations don't tend to return to the scene of the crime.

Gardens Alive exclusive update!: The Question of the Week above originally appeared way back in 2010 on a show that we have chosen for a repeat this week (its Pledge Drive time in Philly). In the five years since, I've learned more about these creatures.

They are still wasps, but at least THIS September (true to the timing of the original questions) they were European Hornets on my lilac. These are big menacing-looking insects that, unlike other hornets, do NOT sting. Yes, they DO look fierce, but they are not a stinging threat. (I proved that through a variety of maneuvers that would have had regular hornets stinging me all over.)

And yes, they were stripping the bark from my lilac this year. It's probably the third time this has happened in 15 or so years of the lilac being out there (so it's not an annual problem). They hung around for a about a week and a half, seemed to devour a lot of bark and then were gone. The lilac—which bloomed its absolute best ever this past Spring—never seemed to suffer any ill effect and still looks great a month later.

I'm guessing that although it looks troubling, their September snacking doesn't harm the plant. In fact, it may stimulate it to grow better!


Identifying the cause of the bark damage is fairly easy.

Beavers and rabbits can only strip bark as high as they can stand.

Black bear damage typically occurs in the Spring. Stripped bark will lay on the ground. Vertical tooth and claw marks may be noticed. Damage will mostly occur on at the 3-5 foot level of the tree, typically conifers 15-30 years old. Damage may be extensive, up to 70 trees in one day.

Field mice (including voles and deer mice) tend to strip bark during the harsh winter. Damage often takes place along the vertical portion of the trunk that lies beneath the snow.

Mountain beaver damage occurs low on the bole of smaller trees. Tooth marks will be horizontal. Claw marks will be irregular. Twigs often clipped quite high on the tree, leaving 2-inch stubs.

Porcupines rely on tree bark as an essential component of their diet. When they are around, trees, especially tender branches in the upper-most parts of the treee, will be substantially and quickly impacted.

Squirrels typically strip bark in late winter or during periods with low acorn or seed production by trees (Fig 2). Horizontal branches seem to be preferred, but have been known to strip the bark off of trunks too (Fig.3).

Chunks of the outermost bark will also be found on the ground (Fig 4). Squirrels are also noted for the amount of surface area stripped (Fig 5).

Shedding Bark

Shedding bark on some trees is a completely normal development. The bark of most young trees is smooth and thin. As the tree grows, the bark layer thickens with the outermost tissue eventually dying. Continued growth pushes the bark outward, causing the outer layers to crack. On some trees, the outer dead layers peel and drop off, revealing the inner layers of bark. Shedding or peeling bark is characteristic of trees such as the sycamore, redbud, silver maple, shagbark hickory, birch, and Scotch pine. The grayish brown bark on a large sycamore tree, for example, flakes off in irregular blotches revealing a cream or whitish gray inner bark. This summer the sycamores have lost larger than normal amounts of bark. The dry fall and record cold of last winter may have loosened more bark than normal leading to the heavy loss of bark. Despite the loss of large amounts of outer bark, there is no cause for concern as the sycamore trees appear to be healthy. On older redbuds, the outer bark on the trunk often falls off revealing orangish-brown inner bark. Long, thin strips of bark may also come off large silver maples.

Cracking and peeling of bark on the south or southwest sides of young fruit trees, red maples, and lindens often indicate a serious problem. Often attributed to sunscald, the damaged bark comes off completely down to the wood. The loss of bark will reduce the vigor and health of the tree and possibly shorten its life. If the trunk eventually becomes completely girdled, the tree will die. Unfortunately, not much can be done to help trees with damaged bark. There is no scientific evidence showing tree wraps prevent sunscald damage. All the loose bark can be carefully removed. However, wound dressings or tree paints are of no benefit.

This article originally appeared in the August 9, 1996 issue, p. 129.