trunk
Quick Summary
The trunk, or bole, is the main stem of a tree, distinct from its limbs and roots. It is composed of wood, which is surrounded by bark. Wood contains xylem, a vascular tissue that transports water and minerals from the roots to the rest of the plant, and phloem, which moves sugars from the leaves.123
The bark consists of inner and outer layers. The inner bark is secondary phloem, while the outer bark includes dead tissues like cork cells, which protect the tree from water loss, insects, and fire. The unique structure and appearance of bark often help identify tree species.4
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