As the tree grows it starts the appearance of rings inside the trunk. Counting the rings of a tree gives a fairly accurate measure of a tree’s age. The growth rings show how the weather has changed and affected the tree’s quality of life over the years. The wider the rings the more growth of the tree and the closer it is to ideal weather conditions. The narrow the rings will indicate less growth due to cold weather or drought conditions. The oldest layer of growth is in the center; the newest growth rings are closest to the bark.
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The outside of the trunk is the bark that protects the tree. Beneath that is the cambium layer, where the tree grows. In the spring, the cambium grows quickly and the ring is light-colored. The ring is darker at the end of each growing season as the cambium grows more slowly. The phloem in the bark carries food made by leaves of the tree. The next layer inside the cambium is sapwood, the part of the tree trunk that carries water and minerals up from the roots to the trunk, branches, and leaves. In the center of the tree is the heartwood, a hard dead core that supports the tree.
Sources[]
- Hoover, Evalyn, Howard Larimer, Sheryl Mercier, Michael Walsh, Dave Youngs, Beverly Tillman, Gretchen Winkleman, Judith Hillen, Ben Wagner, and Sheryl Mercier. The Budding Botanist: Investigations with Plants. Fresno, CA: Aims Education Foundation, 1993. Print.