As anyone who has followed www.TheEarthConnection.org knows, I love trees. Not only do I feel somehow deeply connected with them, but I also find them fascinating.
    I have recently been reading about trees and have learned some interesting things, especially about how trees grow. Now that I know these facts, they seem obvious, perhaps known to most people. But, nonetheless, I would like to share some of what I have learned.
    Trees grow in two ways. They add length, or height, only from the tips of their twigs. Clusters of specialized cells at the end of a twig divide to make the twig grow longer. Thus, the tree grows taller, or spreads more.
    The other way trees grow is by adding girth. In the cambium–the layer just beneath a tree’s bark– cells divide. This division takes place in the trunk, in every branch, in every twig. Thus, as a tree ages, its trunk widens. What was once a twig becomes a substantial branch. The rings inside a tree’s trunk that can be seen when a tree has been cut down show just how much the cambium has expanded in each year of the tree’s life.
    So trees do not grow upward from the ground. A branch growing out from a tree will be the same distance from the ground as long as the tree stands. Branches are not lifted upward as the tree grows.Â
    I was intrigued to learn that a tree’s life underground mirrors its above-ground growth. Just as the tree grows taller and wider each year, so grow the roots underground. As their tips lengthen every year, pushing deeper into the earth, the roots are thickening at the same time.Â
    One more fact–one I find counter-intuitive. The life of a tree is in its outer layers. That’s where the growth is taking place. It’s where the sap runs. The inner part of a tree–ironically called the heartwood–is dead. As life continues growing outward, the work of what was formerly the cambium is complete.  Having become dead heartwood, it is encased in new life. –April Moore