Bark Peeling Off of Maple Tree

Asked July 30, 2018, 1:44 PM EDT

I recently moved onto a property with a large maple tree on it that has been peeling bark since about the middle of June. The layer underneath the bark that is peeling is light/lime green coinciding with areas of lighter grey. This is visible on the uppermost branches. There is a small amount of dead leaves, nothing comparable to the amount of leaves still alive on the tree. Is the tree dead or is it being attacked by some sort of fungus/parasite?

Kent County Michigan

1 Response

While it is difficult to tell from just one picture, your tree may be a Sycamore tree (Platanus Ocidentalis) or a sycamore maple (Acer pseudoplatanus).rather than a maple. The most striking characteristic of these trees is flaking bark. Sycamores are easily identified by their bark which flakes off in big chunks to reveal the pale new bark beneath. They do this because their bark cannot expand as the tree grows.

The London Plane Tree Platanus × acerifolia) also has flaking bark and similar leaves to a maple. Compare your leaves to the photo below which shows sycamore leaves. They are typically larger than maple leaves.

Sycamore Leaves

Silver maples (Acer saccharinum) is the only maple with peeling bark. Your tree is not a silver maple, which has distinctive silvery leaf backs.

Sometimes a maple or other hardwoods can drop bark. As long as there’s healthy bark underneath the peeling layers, your tree is OK. But if you see these other signs, your tree needs a bit more help:

  • Bark falls off after frost, which usually happens on the tree’s south or southwest side. Any sudden swing in temperature can make trees shed bark and crack under stress.
  • Bark falls off after excessive heat, which, like frost damage, strips bark down to the wood.
  • Bark falls off an unhealthy tree, which means you’d see other signs of stress such as cankers, sap, or dead leaves and twigs.
If you find any signs of pest or disease—sawdust, oozing cankers, dead leaves, or a fuzzy fungus—have a professional arborist check it out. He’ll let you know if you can treat the problem or if you need to remove it to keep other plants on your property out of harm’s way.

Hardwood trees that have peeling bark may be suffering from a fungal disease called Hypoxylon canker. Peeling bark caused by this disease is accompanied by yellowing and wilting leaves and dying branches. In addition, the wood under the peeling bark is covered with a mat of fungus. There is no cure for this disease and the tree should be removed and the wood destroyed to prevent the spread of the fungus. I see no sign of fungus (black mats that look wet) on your limb. Also other parts of the tree would likely be affected.

Your first step should be to positively ID your tree. As mentioned above, it is quite normal for certain trees to flake off bark and end up with patchy colored bark. You can find an arborist by calling a tree service (look in Yellow Pages or online) and ask if they have a certified arborist on staff.