Trees Are So Weird

mostly dead

Trees are mostly dead. The living part is a thin layer of cells called the cambium, responsible for growth. The bulk of a tree is dead tissue (wood) that provides structure and transport.

• 🌳 The living cambium layer is only a few millimeters thick, sandwiched between dead wood (xylem) and dead bark (phloem).
• 💧 Xylem cells die and hollow out to form wood, creating a network of pipes that transport water via transpiration pull.
• 🌿 Phloem cells also die, but their companion cells keep them functional as living sugar pipelines and signal cables.
• 🪵 Wood is essentially stacked layers of dead xylem cells, forming the tree's structural support and water transport system.
• 💀 Damaging the bark kills the living cambium layer, which can lead to the tree's death.

A diagram of a tree stump showing different colored layers, with an arrow pointing to the outermost living layer labeled 'ALIVE PART'.