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

Purple Lilacs
(Image credit: Matthias Rohrberg)

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.

Jackie Carroll

Jackie Carroll has written over 500 articles for Gardening Know How on a wide range of topics.