Years with this quote from John Muir: “Among all the varied productions with which Nature has adorned the surface of the earth, none awakens our sympathies, or interests our imagination so powerfully as those venerable trees which seem to have stood the lapse of ages, silent witnesses of the successive generations of man, to whose destiny they bear so touching a resemblance, alike in their budding, their prime and their decay.” The authors initially set out on a journey of discovery hoping to include some twenty-four species of trees that live over a thousand years. Their list rose to a hundred and the list is still growing. They comment that some of the world's oldest and most impressive inhabitants have already begun their fourth, fifth, sixth, or even seventh millennium. They report that a carbon-dated small-leaved lime tree (Tilia cordata) in a woodland in the west of England has already celebrated its six-thousandth birthday, and a common yew (Taxus baccata) in Fortingall, Scotland, could be nine thousand years old.
When I came home to find my huge beautiful Monterey pine tree was now an impressive stump, one question that could now be answered was its/her age: forty-two years old. As just about everyone knows, the age of a tree can be determined once it is cut down, by the number of its concentric growth rings. It is part of American tree lore, because this is so for trees that grow seasonally in temperate zones. In good years, the growth rings are broad; in bad growing years, such as a drought year, the rings are close together.
Tree Anatomy and Physiology
What are tree rings, anyway? The question led me to learn about the nutrient transport system inside of trees. Water travels upward through the trunk from its underground roots. A large root called the taproot grows straight down, other roots grow out laterally and branch out to hold the tree down, while very fine root hairs at the ends of roots take water and dissolved minerals and salts from the soil. If we could see this branching root system, it might resemble the structure and size of tree branches that we can see growing up from the trunk (as above, so below). Inside the roots, the tree changes the water into a liquid called root sap, which moves up the trunk in a layer of wood called the sapwood or xylem, comprising masses of miniscule tubes. Inside the xylem, root sap moves through the branches and out to nourish every leaf. Each green leaf is a little photosynthesis unit, which uses moisture and sunlight to remove carbon from the carbon dioxide in the air from which it makes sugars to feed the tree and oxygen to release into the air.
These sugars are then carried through strings of cells out from the leaves, outward and downward, to nourish the rest of the tree. These cells form a layer on the outside of the xylem, just beneath the bark of the tree, called the phloem. In between the xylem and the phloem, there is a thin layer of stem cell tissue, the cambrium, which runs from the leaves to the roots. All along the trunk there are medullary rays or conduits that link these elements with the outside of the tree, enabling the trunk of the tree to grow in diameter as the tree grows. The job of the cambrium is to create more xylem vessels on the inside and more phloem tissue on the outside. As xylem and phloem layers cease functioning and die, dead xylem becomes the heartwood, new xylem the sapwood, while the dead phloem is incorporated into the bark. Usually, new xylem is laid down in the spring and is wide and thin-walled; in the summer, the xylem is narrower, thick-walled, and dark in comparison with the spring xylem. These differences result in one growth ring per season. Having the cambrium close to the bark, the trunk of a tree can grow thicker year by year, some even for thousands of years.
My premed courses in college, medical school, internship, and residency were years of intense learning. There is an immense amount of information that a doctor of medicine needs to learn, and upon which we were tested, over and over again, with class rankings and the next rung up the professional ladder dependent on how much and how well we learned. Left out was the wonder of how the body was constructed and worked, or how the meeting of an ovum and sperm came with elaborate guidance on how to grow into a baby, or how a baby grows smoothly into an adult human being. There are glimpses of wonder along the way in the training of a doctor, but no one talked about such things. Wonder is all too often left behind in the process of becoming an adult, as well. When it is, an essential spiritual element is missing. We humans come into the world with a sense of wonder, expressed and seen most clearly in childhood. Wonder is a precious sensibility to retain. Wonder and imaginative play go together in childhood and are together in the mind of creative adults who can be fascinated and enthralled by their new discoveries that then stimulate ideas and art. Wonder makes living on this planet an adventure. Then as we become aware of the vulnerability of life, some are called to save lives, others to preserve nature.
To grow like a tree is to be part of an interconnected mutually supportive circle of life: from soil to tree to water vapor to clouds to rain to soil and up again (the big picture) as well as a mini-ecosystem that sustains and nourishes this one tree. Whether as one tree on a hillside or one tree among millions in a boreal rain forest, this is so for every tree that lives naturally.
To spread the ashes of a loved one in the forest or woods, or under a special tree, or plant a tree in memory of that person is a ritual link to this large circle of life and also an actual link when ashes are spread or remains are buried: ashes to ashes, dust to dust, and dust to soil. The Earth prevails. What is left of our once-embodied selves, in turn and in time, will be incorporated into the planet. The fern forests and the trees gave us oxygen and nutrients to grow from a single cell into a human being, which we recapitulate in the uterus. Everything on Earth began with her, grew out of her, and will return to her. This is Mother Earth as womb and tomb, personified as the Great Mother of ancient and indigenous peoples: Our Mother who art the Earth.
2
GIVING LIKE A TREE
Inside our mother's uterus, each of us began as a fertilized ovum that grew into an embryo, then into a fetus, developing organs until they could be functional, gaining weight and size until, in approximately nine months of gestation, we were delivered into the world as a newborn baby. While inside our mother's body, we received oxygen and all the necessary nutrients to grow through the placenta that connected us to her physiology. In her body, she—our personal mother—produced the nourishment and eliminated the waste products of our metabolism, and maintained homeostasis, the steady environment in which her body's temperature, acid-base balance, and myriad other functions are kept within the range that sustains life. Mother Earth has been doing the same for us, and will continue to do so if we don't overwhelm her physiology with our numbers and toxic wastes.
As I learned about the evolution of trees and how Earth became a planet on which life was possible through the activity of trees, I realized that without trees, there would be no “Mother Earth.” Earth, air, water, and fire—these basic elements—come through trees. Without trees, Earth would not have a breathable atmosphere, soil for vegetation to grow, or water fit to drink. Sparks would not become fire without oxygen and combustible matter, which trees continue to make. All life has grown out of the body of the Earth; evolution became possible because what is needed is provided. Earth in its abundance gives to us like a tree.
It is spring and I am in New Mexico editing and adding to Like a Tree, as I revise the first draft into its final state. There is a 120-year-old apple tree in full bloom outside the window; its white blossoms delicately tinted with pink are gorgeous. I think of how trees also provide us with beauty, and that this one in particular, a Wolf River apple, will provide a harvest crop of crunchy red apples, as well. Food right off the tree for people and horses that can be further transformed to last for many, many more months when they are canned. Spring-light green is the color filling out the once bare-limbed trees near the creek, trees whose roots hold down the earth, each part of a watershed, conserving water in its banks to be gradually released later, and preventing soil runoff from the sudden, infrequent thunderstorms. On hills above the creek and lining dry arroyos that testify to the existence of flash floods are the evergreen juniper and pine trees that cover the rust-colored hillsides in this high-desert country. So much of the beauty around us is created by trees. Here the tree landscape doesn't resemble that of Northern California,