Maple tree bark

Asked April 13, 2020, 3:56 PM EDT

I have four silver maple trees in our back yard that have developed scaling bark. The squirrels have been taking off this bark as they run up and down the trees and it appears they are licking sap as well in exposed areas. Will the removal of this layer of bark cause the trees to die??? Thank you Gary

Kanabec County Minnesota

1 Response

Thanks for your question. I understand the concern in seeing bark fall off and leaking sap underneath—whether it’s harmful to the long-term survival of your trees depends on why the bark is falling off.

Best case scenario, it could be relatively benign. It’s normal for older silver maples to develop scales and plates in their bark (see photo below from the Ohio DNR website) and for bark to shed from time to time as the tree is growing. Around this time of year, sap is flowing throughout the tree due to the swings in daytime vs night-time temperatures. If the layers underneath the top-layer of wood are growing faster than the top layers, this may cause some of this flowing sap to leak, which might be what you’re seeing.

Silver maples are also very prone to storm damage and weather stress, however (especially with that last late frost and the major swings in temperature we’ve been seeing this spring). If the tree appears to be otherwise healthy, to help, you could try adding mulch around the tree (no deeper than 3 inches and not within 6 inches of the base of the tree to prevent moisture damage) and watering it if the soil is dry to hydrate the tree.

But if it’s showing other signs of stress or damage, such as cankers, dead branches, fungus, other abnormalities in the bark, large amounts of sap leakage, or large amounts of exposed areas on the trunk, I would recommend contacting a professional arborist to come take a look—they’ll be able to help you further diagnose the problem and make recommendations on the best course of action. Here is a link with information on how to go about finding and hiring a tree care professional:

https://extension.umn.edu/planting-and-growing-guides/how-hire-tree-care-professional