Layers of a Tree

Even though trees may seem that they have only two  layers, the bark and the center of the tree they actually have many more. The first layer is called the outer bark. This outer layer of bark protects the tree from bugs, bacteria, and animals that may gnaw on the tree. It also protects the tree from moisture in the air or rain and when the temperature is really hot or cold. The second layer of the tree is called the inner bark. The inner bark is where food passes to the rest of tree. This layer isn't vital to the tree as it later becomes part of the outer layer of bark. The third layer of a tree is the cambium cell layer. This layer has a greenish color which if you have ever peeled the bark of a branch and you see a greenish layer that is the cambium. The cambium helps the tree grow up. It is a very important layer of the tree because if the tree did not have this layer then it probably would have a hard time growing. The fourth layer is called the sapwood. The sapwood is like a pipe used to move water from the trunk and the roots of a tree to the leaves just like a pipe carries water to the sink from a reservoir or a lake or river. Later, when the tree grows part of the sapwood grows into the heartwood. The heartwood is the fifth, the last, and the middle most part of the tree. The heartwood is the strongest part of the tree and it holds the tree up. Those are the layers of a tree.