In botany, the trunk (or trunk) is the main wooden stem and axis of a tree, which is an important feature in identifying trees, and which often differs markedly from the bottom of the trunk to the top, depending on the species.
The trunks are both plants woody "true" and non - woody plants such as palms and other monocots, although the internal physiology is different in each case. In all plants, trunks thicken over time due to the formation of secondary growth (or in monocots, pseudo-secondary growth). Logs can be vulnerable to damage, including sunburn. The logs that are cut on the log are generally called logs and if they are cut to a specific length they are bolted.
The trunk is made up of five main parts: the bark, the inner bark, the cambium, the sapwood, and the heartwood. From the outside of the tree working first, you see the bark, this is the protective layer of the trunk. Below this is the inner bark that is made from phloem.
The phloem is the way the tree carries food from the roots to the shoots and vice versa. The next layer is the cambium, this is a very thin layer of undifferentiated cells that divide to replenish the phloem cells on the outside and the xylem cells on the inside. Directly within this is the sapwood or living cells of the xylem. These cells carry water through the tree.
Finally, in the center of the tree is the heartwood. The heartwood is made up of old xylem cells that have been filled with resins and minerals to prevent other organisms from growing and infecting the center of the tree.
