Caring for tree after machinery damage

Q: I had my front yard dug up due to a collapsed sewer line. The backhoe damaged a six inch square of bark on one side of my mature dogwood tree. Is there anything I should do to ensure better survival of the tree?

A: Unlike mammals, which heal an injury by covering over it, trees deal with damage by forming a layer of dense cells inside the tree around and under the wound. Oxygen contacting the damaged cells stimulates the tree’s protection response to proceed as quickly as possible.

The best help for your tree is to clean the edges of the scrape with a razor knife, removing any loose bark. Do not apply wound dressing, tar, or paint. Water regularly to reduce stress and place mulch under the tree to keep the soil cool.