The Science Behind Tree Wound Healing

Introduction

When a tree is pruned or injured, it doesn’t “heal” like human skin. Instead, trees use a process called compartmentalization to seal off damage and prevent decay spread. Understanding how trees respond to wounds helps explain why proper pruning cuts are essential.

How Trees Respond to Wounds

1. Compartmentalization of Decay

Trees create chemical and physical barriers around damaged tissue. These barriers:

• Block pathogens
  
  

• Limit decay spread
  
  

• Strengthen surrounding wood
  
  

This is why where you make a pruning cut matters so much.

2. Callus Formation

Trees grow callus tissue around the wound’s edge. Over time, this callus can close over the wound if:

• The cut is clean
  
  

• It’s made at the proper branch collar
  
  

• The tree is healthy
  
  

3. Energy Distribution

Trees allocate energy to wound response, which is why improper pruning can stress a tree.

Why Proper Pruning Matters

Incorrect cuts (flush cuts, stubs, tearing bark) make it harder for trees to seal off damage. Poor pruning leads to:

• Rot
  
  

• Slow closure
  
  

• Weak regrowth
  
  

Internal decay spread