What Are the Parts of a Tree?
Trees are absolutely an important part of our natural world to
Hi, I'm Jacob Taxis for About.com. In this video, you will learn about the parts of a tree.Trees are living organisms—and they can live a very long time. That's a good thing, because without the clean oxygen they freely produce, we couldn't live on this earth. Amazingly, the oldest tree in the world, at approximately 13,000 years old, is the Jurupa Oak tree in California. Trees are quite complex and have distinct parts that serve very specific functions for the well-being of the tree itself. Overall, a tree is made up of roots, a trunk, and a crown.First, the roots. Roots are the part of the tree, usually below the surface of the soil, that absorb water and ground nutrients and anchor the tree in the earth. Through a process called phytoremediation, tree roots clean the soil around them by absorbing pollutants. The taproot of a tree is the center root that grows vertically downward. All of the other tree roots, like surface roots, for example, sprout from this taproot. As the tree grows above, so do the length and thickness of the roots below.Next, the trunk. The trunk of a tree is made up of outer bark, inner bark, cambium, sapwood, and heartwood. The outer bark is a protective layering composed of cork cells. The inner bark of a tree acts as the tree's highway system; it transports sugars and nutrients and also aids in protection against herbivores. The cambium aids secondary growth within the tree by producing cells. Sapwood is the outer layer of the secondary wood that sends water and minerals to the tree's crown. This layer is living. Heartwood, on the other hand, is the strong, dead, inner core of a tree that resists decay.Finally, the crown. The crown is what it sounds like: it's the very top portion of the tree and it consists of branches, twigs, and leaves. Branches are the extended limbs of trees that are connected to the central trunk. Boughs are the larger branches, and twigs are the smaller branches. Leaves sprout from twigs and, with the help of sunlight, produce the tree's food in a process called photosynthesis. Chlorophyll, the substance that gives leaves their green color, utilizes carbon dioxide and water to create carbohydrates for the tree to feed on.Whether preventing storm water run-off, cleaning the air, or providing us with life-giving oxygen, trees are absolutely an important part of our natural world. Thank you for watching. For more, visit About.com.