Healing its wounds

When the tree is damaged, it protects itself by sealing the wound as quickly as possible. Wood cells form around the edges of the wound and the tree forms a callus, often shaped like a pair of fleshy lips.

This callus is not exactly like a scab that forms on an animal. A scab is often temporary and disappears as new tissues are created. But the tree will never regenerate the damaged tissues – it can only build new wood on top of the scar. Even after the wound closes up, the scar will always remain.