* Protection: The outermost layer of bark, called the periderm, is made up of dead cells. This layer acts as a shield against:
* Physical damage: Bark protects the tree from injuries caused by animals, insects, weather, and even human activities.
* Disease: It acts as a barrier against fungal and bacterial infections.
* Temperature fluctuations: The periderm helps regulate the tree's temperature, protecting it from extreme heat or cold.
* Water loss: Bark helps prevent the tree from drying out.
* Transportation: The layer beneath the periderm, called the phloem, is responsible for transporting sugars produced by the leaves to the rest of the tree.
* Structure: The cambium, a thin layer of cells that sits between the phloem and the xylem (which carries water upwards), is responsible for producing new bark cells.
* Shedding: As the tree grows, the cambium produces new bark cells, pushing the older ones outward. These outer layers eventually die and become part of the protective periderm. This process often results in the bark appearing to flake or peel off, revealing the newer, smoother bark beneath.
In summary, bark is a complex and vital part of a tree's structure and survival. It acts as a protective shield, facilitates the transport of nutrients, and contributes to the overall health of the tree.
