No, bark is not entirely dead cells; it is composed of both dead and living cells working together to protect a tree.
Understanding Bark's Composition
Bark serves as a tree's vital protective tissue, much like human skin, defending against threats such as insects, fungi, fire, and deer. Its complex structure includes different layers, some of which are dead, and others that are very much alive.
Based on the provided reference, bark includes two primary components relevant to this question:
- Cork Layer (Outer Bark): This is the part of the bark you typically see and feel on a tree. It is made up of dead cells. These dead cells form a rugged, often textured outer layer that provides the primary physical barrier.
- Cork Cambium: Located beneath the cork layer, the cork cambium is comprised of living cells. This active layer is responsible for producing new cork cells, contributing to the growth and renewal of the outer bark.
| Bark Component | Cell State | Function |
|---|---|---|
| Cork Layer | Dead | Primary protective barrier, insulation |
| Cork Cambium | Living | Produces new cork cells, facilitates growth |
The Protective Role of Bark
The combination of dead and living cells in bark ensures comprehensive protection for the tree. The dead outer layer offers robust physical defense and insulation, while the living cambium layers beneath allow for repair, growth, and continuous adaptation to environmental stresses. This dual nature highlights bark as a dynamic, essential part of tree biology.
