Environment
What is lost when we destroy a forest? In an excerpt from her new book, Our Green Heart, renowned biochemist and botanist Diana Beresford-Kroeger reveals the profound and far-reaching effects of an abundant year — and issues a call to action.
Mast is the old word for food that dates back to the earliest years of the human family, found in Sanskrit and in Old Gaelic as meas. Mast comes from the countryside. It is a gift of nature. And sometimes, only sometimes, when the pressure points are perfect, nature produces an extra-fruitful year, so that all creatures in the web of life obtain an excess of food. This is called a mast year.
That such a year is upon us is first noticed in the forest. In a mast year, trees of all the arboreal families hear the call. Each tree grows a larger canopy of leaves to fulfill the promise of the harvest ahead. Then the entire forest, as a community of care, produces seeds, nuts, nutlets and acorns in excess. It is a crop representing a large expense of both time and energy, and its gift is a boon to every living thing in the forest and beyond.
The seeds are filled with the riches of first-class plant proteins, carbohydrates, essential fats, and the phytochemicals that are precursors to vitamins and plant hormones. Minerals are also present within the seed’s testa, or outer coat, as micro- and macro-elements. This abundance carpets the forest floor, for mile after mile. The community of a forest, any forest anywhere, has a will of its own. Somewhere in the genetic pool of knowledge deep within a tree, there is an understanding of future weather patterns. The accuracy of this understanding is a life-or-death matter for a tree and, consequently, for a forest ecosystem. It provides the base of information from which the tree must decide when and where to expend its most precious resources, decisions trees make judiciously, even ruthlessly when necessary. Under stress, trees produce more pollen; if the going gets really tough, they use a biochemical axe, aborting seeds, leaves and even branches.
Any native forest holds evergreen, deciduous evergreen and fully deciduous tree species. This tapestry of varying greens produces a cooling shade system in daylight. Under the towering and spreading canopies of ancient trees, the youngest can dance with their virgin leaves protected from the harshest ultraviolet rays of the sun. These killer UV rays have been amplified by the greenhouse effect of rising temperatures. The understorey tree species, in many older forests often holding on to a great age, are protected. Through this sub-layer, nimble vines begin the uphill battle to reach the sun. If successful, these climbers also bear seeds in descending cascades, sometimes reaching down to the living forest floor, which holds many secrets in its earthbound folds.
The ferns have been the companions of trees since ancient times. They, in turn, allow the mosses, club mosses, liverworts and ground lichens to survive. Living deeper still, the fungi make a home in the soil and sometimes within the trees themselves. These invisible, endogenous fungi are from the higher orders of the cryptograms and are the masterminds of many medicines of the forest. They mix with the life forms in the forest floor, which foams with underground activity. The diversity of the upper storeys is always a reflection of what is underfoot.
Biodiversity blooms in a mast year. In the spring, the male and female reproductive centres kick in full tilt. Some trees are monoecious, meaning they possess both male and female organs; others are dioecious, meaning separate male and female trees exist. The sexual hijinks in a forest beggar belief, and all these sexual routes have teasers. Some are sweet, from the female members, filled with sugars from the female glands where the ova lay in wait. Others, in which proteins are stacked, waiting for release at germination, are more sour. These sour-tasting treats of protein-filled pollen are the bodybuilders of the diet of many insects and birds. At all points in the passage of spring, though, the pollinating insects are fed, from butterflies to bees. These small forest rangers are always on standby to enact pollination. Some travel as far as 16 kilometres from the focal point of the forest to partake.
But with native forests coming down all over the globe, a serious genetic erosion is also occurring: forests are losing their biodiversity. This is happening due to ignorance, greed, war and simple carelessness. The mother trees of ancient pedigree are almost gone. Such trees carry a genetic flexibility from past generations into a growing forest. This injection of germ plasm into the gene pool is essential if we are to combat climate change. The germ plasm from ancient trees has seen and endured variations of temperatures in the past. Their epigenetics hold a memory of stress. A mixture of very old trees with very young trees is healthy for any forest anywhere. The grandparent plasm can inject the grandchild with the knowledge necessary to survive.
With native forests coming down all over the globe, a serious genetic erosion is also occurring: forests are losing their biodiversity.
Time is running out to accomplish the task of saving these grandparent trees. The northern temperate forests have lost so much already. Of the Ulmaceae family, the rock or cork elm, Ulmus thomasii, went first, followed by the beautiful, weeping American elm, U. americana. In eastern Canada, very few massive American arborvitae, Thuja occidentalis, are still seen. The last great giants of T. plicata, the sister tree called the western red cedar, are under attack on Vancouver Island. The custard apple of the Annonaceae family and the pawpaw, or Asimina triloba, have vanished from the wild in southern Ontario. Of the Oleaceae family, the black ash, Fraxinus nigra, went first, followed by the white ash, F. americana; and far too little notice is paid to the loss of the profoundly important blue ash, F. quadrangulata.
Only a handful of pitch pine, Pinus rigida, remain on the shores of the St. Lawrence River. This member of the Pinaceae family is a giant in the medicinal world as a source of antiviral medicine. Also in Canada, there are the two lost ladies of the Magnoliaceae family: the beautiful Magnolia acuminata, the cucumber tree, whose numbers are larger in one garden in Ireland than in all of Canada, and Liriodendron tulipifera, the tulip tree, which was so useful to the Huron people. All the oaks, the Fagaceae family, show the botanical world how badly they have been beaten, especially the white oak, Quercus alba, which is down to retrograde species with crooked trunks, where once upon a time these trees stood up to the stars like soldiers.
The loss of these forest trees, and many, many others, also affects the streams, rivers and estuaries feeding into oceans, severely reducing the plumes of humic and fulvic acid that end up in coastal waters. These giant molecules are the last bonus of the forest mast, transcontinental carriers of iron, the vital metal that allows algae to divide. From this less obvious forest food, oceanic mast explodes. Even the great whales benefit, whether from a lifeline released directly into their calving grounds or from one dispersed across the oceans.
Mast might be the old word for food, but it is also the secret key to life on this planet today, as it will be tomorrow. The design for sustaining every creature has always been here. It is just a question of opening both eyes to look and see.
Excerpted from Our Green Heart by Diana Beresford-Kroeger. Copyright © 2024 Diana Beresford-Kroeger. Published by Random House Canada, a division of Penguin Random House Canada Limited. Reproduced by arrangement with the Publisher. All rights reserved.
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