Bark loss on a favorite tree can be alarming. There are many reasons why trees lose their bark, though. These reasons range from the perfectly harmless to the possibly fatal.
1. Growth Habit
Some trees naturally shed bark as they age. Sycamores, some maples, and paper birch are common and well-known tree varieties that periodically shed bark. Although it can look alarming, if a tree naturally sheds bark then you don't need to worry about its health in relation to bark loss. If you are unsure of the variety of tree in your yard, a tree professional can identify it and let you know if the bark loss is part of the tree's natural growth habit.
2. Animal Browsing
Deer and other urban and suburban wildlife may peel the bark off trees. They are seeking out the tender and nutrient-rich cambium layer that lays just beneath the bark. Overbrowsing, though, can kill a tree and young trees are particularly susceptible to damage. The best defense is protecting the trunk against browsing. Damage is often greatest in winter and early spring when food sources are scarce. Your tree service can put special cages or wraps around the trunk to protect them.
3. Mechanical Damage
Bumping into a tree trunk with a lawn mower, scarring the bark with a weed trimmer, or rubbing off bark with a hammock rope are all examples of mechanical damage that leads to bark loss. Installing a mulch ring around the trunk so there is no need to approach it with lawn equipment can go a long way toward preventing this sort of bark loss. It's also a good idea to avoid tying things around the trunk, or at least use wide straps that cause less damage.
4. Pest Infestation
Certain pests, both of the insect and the disease variety, can lead to bark loss. The most common bark-damaging pests are probably the larva of various moths and beetles that burrow into the cambium layer beneath the bark to feed and mature. As the cambium layer is decimated, the bark begins to flake off. Treatment depends on the exact pest or pathogen, so you will need a tree service to diagnose the problem so they can apply the appropriate pesticide or other treatment.
5. Lightning Strike
A lightning strike doesn't always result in highly visible damage. In some cases, the only immediate sign of a strike is a loss of bark along one side of the trunk. Treatment entails providing sufficient water and fertilizer to the tree as it recovers. It can take a whole growing season before the extent of the damage and whether the tree will survive becomes obvious. If the tree continues to thrive, no further treatment will be needed.
Contact a professional tree service if you are concerned about bark loss on any of the trees in your yard.