Forests and the “Water Engine”

“The groves were God’s first temples.” —William Cullen Bryant


When I was growing up in the Eastern Townships of Québec, my dad took us every


Collecting Maple sap (photo by Merridy Cox)

spring to the local maple tree farm. I remember hiking through knee-deep snow among slim maples with buckets hanging off spiles leaking sap. Most trees had one tap but some wider trees had two. The thing to do was drip some sap onto snow and enjoy a “snow cone”. I preferred to drink the sap straight, enjoying its semi-sweet complex flavour. I even preferred it to the maple syrup, made by boiling the sap in the sugar shacks, and to maple sugar—which I found far too sweet and granular for my taste. It turns out that tree sap—particularly sap from a maple, birch or walnut tree—is extremely good for you and now considered the most valuable product you can get out of a tree. The minerals, nutrients, enzymes, and antioxidants in maple sap provide a power drink that tastes delightful.

Tree sap is mostly water.

Water runs this planet. Like an efficient organic “engine,” it courses through the veins, arteries and capillaries of Earth, nourishing, recycling and communicating. At the heart of water’s engine are trees, pumping, breathing, and dispersing.


Ash tree in Little Rouge River woodland, ON (photo by Nina Munteanu)

Trees are highly evolved water management specialists, writes Jim Robbins, author of The Man Who Plants Trees. “A forest is a soft carpet on the landscape that allows a downpour to reach the ground gently rather than in a torrent.”This one fact reminds us of Nature’s intricate fabric of intelligence and how water works with all the components of our natural world. Trees and forests are the highest functioning members of ecological society, Robbins tells us. They “create rain; render … toxic wastes in the soil harmless; neutralize harmful air pollutants in their tissue; offer shade; provide medicine. They sustain wildlife [with] food and shelter. They are the planet’s heat shield, slowing the evaporation of water and cooling the earth. They generate vast clouds of chemicals that are vital to … the earth’s ecosystems and … to our health and wellbeing. They are natural reservoirs—as much as a hundred gallons of water can be stored in the crown of a large tree. The water they release is part of a largely unrecognized water cycle.”

The deep roots of mature trees bring up negatively charged water along with vital minerals and trace elements, acting as bio-condensers and “harmonizing positive energy from the sun with the negative energy of the earth,” writes Alick Bartholomew, author of The Spiritual Life of Water. Evapotranspiration from leaves of trees and shrubs is a balanced creative energy, he says.


Forest swamp, ON (photo by Nina Munteanu)

Trees are the lungs and air conditioners of our biosphere. Scientists in Germany and the UK demonstrated that trees create and release atmospheric aerosols—biogenic volatile organic compounds such as alcohols, esters, ethers, carbonyl, terpenes, acids and other compounds—that essentially filter the sun’s radiation; and they do other things we still don’t understand. Terpene aerosols help create clouds and produce an albedo effect, one that reflects more sunlight back into space. One large tree, for instance, produces the cooling effect of ten room-sized air conditioners operating 24 hours a day.

The tree “is a chemical factory,” says botanist and biochemist Diana Beresford-Kroeger. They broadcast a host of chemicals into the environment that may travel for hundreds of kilometres, as well as affect the immediate area. Researchers testing California’s Sierra Nevada forest found 120 substances, of which only 70 could be identified. Aerosols released by trees are part of a sophisticated survival strategy, Beresford-Kroeger adds. Two studies published in 1983 showed that willow trees, poplars and sugar maples warn each other about insect attacks; undamaged trees then pump bug-repelling chemicals to ward off the attack. Black walnut trees emit juglone, an aerosol that repels competing nearby plants and some insects. Some tree roots emit a volatile substance that attracts useful fungi. Karban and his team at the University of California–Davis, demonstrated that airborne communication between individual sagebrush plants (called “eavesdropping”) helped neighbouring plants resist attacks.

Diana Beresford-Kroeger

Diana Beresford-Kroeger

Beresford-Kroeger believes that trees help maintain the health of the natural world, as they constantly shower healing chemical mists into the air. “These substances are at the heart of connectivity in nature,” says Beresford-Kroeger. For instance, during a walk through a pine forest on a warm day, the sharp pungent smell of pinene (a monoterpene), helps to relieve asthma. Another monoterpene aerosol, limonene, has an ability to fight cancer, demonstrated by Dr. Michael Gould at the University of Wisconsin.

The notion that forests are linked to health is practised seriously in Europe and the East, in countries such as Japan, Russia and Korea. Shinrin-yoku (Japanese for “forest bathing” or “wood-air bathing”) is a recognized practice in the East and is gaining interest in the West as a natural form of aromatherapy and relaxation therapy.

Robbins shares the following story about Dr. A. Kukowka, a professor of medicine in Greiz, Germany, who recounted his experience beneath a crown of massive yew trees on a warm day. At first disorienting, the experience became one of exhilaration in which he envisioned paradise, angelic music, and felt “indescribably happy.” Kukowka concluded that the terpene emitted from the trees had affected him.

Is this a story of fancy or does it have some validity? Why do we feel so good around trees and in the forest? And why do some forests please us more than others? When I enter a forest or woodland, a calming force descends upon me; perhaps it is the healing mist of trees. My mind quiets and embraces a state of meditative wellbeing, soothed by the gentle rustle of leaves or the cursive clanking of tall poplars in the wind.

Many of us feel a sense of peace in a forest. I have no doubt that this is the result of several factors including sounds and frequencies (e.g., infrasound), increased negative charge, scents, wood essential oils, genetic heritage and memory, and simple aesthetic appreciation and beauty. I write more about this in later chapters (of my book “Water Is…”).

Forest conifers Metchosin

Forest in Metchosin, BC (photo by Nina Munteanu)

You don’t even need to enter the forest; some of its value is in simply seeing and being near trees. Researchers in Europe and Japan found that the amount of green space and proximity to a person’s home reliably predicted mental and physical health. Anxiety and depression was significantly reduced in the presence of green space. Vegetation creates “a halo of improved health.” Dr. Frances Kuo at the University of Illinois demonstrated that just seeing a tree helps cognition and promotes a sense of wellbeing.Kuo strongly believes that lack of trees is debilitating to general social health. “A disappearing urban forest leads to psychological, physical, and social breakdown,” says Kuo, “Just as animals in unfit environments develop certain behavioural and functional pathologies, we may see more child abuse or crime or their problems when people live in unfit environments.”

Attention Restoration Theory suggests that a human-made environment of objects—cars and buildings—requires high-frequency processing in the brain; while a landscaped environment allows the observer to relax his or her attention, resulting in reduced muscle tension, lower heart rate, and a generally less stressful physiology. What naturally appeals to us, what is considered beautiful, while subjective, also follows a kind of “universal” tendency. For instance, a Harvard Medical School study showed that people gravitated to rounded edges and that the amygdala (the part of our brain that registers fear) was more active when people looked at sharp-edged objects. Symmetrical shapes are generally considered more appealing than asymmetrical ones. Shape (e.g., symmetry), texture, tone, height and colour all play a role in determining how mind, heart and spirit function in the creative process. A study published in 2000 by environmental psychologist Nancy Wells found that ample daylight and greenery boosted attentiveness, focus, and academic performance.


Mimico Creek, ON (photo by Nina Munteanu)

Bartholomew describes four geologic periods when forests flourished on this planet. The first was the Carboniferous, 350 million years ago, when land vertebrates established. The second was the Jurassic, 170 million years ago, when dinosaurs flourished. The third, the Eocene epoch, 60 million years ago, witnessed the first primitive mammals. The last, the Holocene epoch, which began some 500,000 years ago, ushered in the cultures of modern humanity. “Perhaps,” says Bartholomew, “in each case the forests delivered a boost in the oxygen content of the atmosphere, which may have been a trigger for an evolutionary explosion of life forms.”

Ten thousand years ago, the land along the Mediterranean was covered in mixed forests of conifers and oak, Bartholomew shares. Lebanon’s forests provided the timber for the exploring ships of the Phoenician empire in the third century BCE. North Africa, a fertile forest two thousand years ago, is now a desert. A thousand years ago, three quarters of Europe was forest. Today forest and woodland cover only one fifth of Europe.

Deforestation doesn’t just create erosion and loss of oxygen; it interferes with the full hydrological cycle that links precipitation with groundwater circulation, and the important energy exchange involved. A reduction in water vapour, otherwise generated by natural forests, creates an imbalance that promotes greater contrast between water-abundant areas and those without; this results in flooding on the one hand and desertification on the other. Dominick Spracklen and his colleagues suggest that, given the role of trees as the planet’s “air conditioners,” one of our primary climate mitigation measures should include planting indigenous trees.

Tree maple-sugar fall-LR

My old maple tree, Little Rouge River woodland, ON (photo by Nina Munteanu)

Russian physicists Anastassia Makarieva and Victor Gorshkov argued in 2007 that forests make rain. Their meteorological theory states that forests function as biotic pumps; they not only function as carbon sinks or havens of biodiversity, but also provide an essential role in the hydrological cycle and climate.

The proportion of the world’s surface covered by forest was once close to 75 percent, Bartholomew writes. It dropped to 50 percent in medieval times and now to 25 percent.




Baldwin, Ian and Jack Schultz. 1983. “Rapid Changes in Tree Leaf Chemistry Induced by Damage: Evidence for Communication Between Plants”. Science 221 (4607): 277–279.

Bartholomew, Alick. 2010. “The Spiritual Life of Water”. Park Street Press, Rochester Vermont. 338 pp.

Benyus, Janine. 2002. “Biomimicry: Innovation Inspired by Nature”. William Morrow Paperbacks. 320 pp.

Beresford–Kroeger, Diana. 2003. “Arboretum America: A Philosophy of the Forest.” University of Michigan Regional. 214 pp.

Farmer, Edward E. and Clarence A. Ryan. 1990. “Interplant Communication: Airborne Methyl Jasmonate Induces Synthesis of Proteinase Inhibitors in Plant Leaves”. PNAS 87: 7713–7716.

Hance, Jeremy. 2012. “New Meteorological Theory Argues that the World’s Forests are Rainmakers”. Mongabay, February 1, 2012. Online:

Karban, R., K. Shiojiri, M. Huntzinger, and A.C. McCall. 2006. “Damaged-induced Resistance in Sagebrush: Volatiles are Key to Intra- and Interplant Communication”. Ecol. Soc. Amer. 87(4): 922–930.

Munteanu, Nina. 2011-2013. “The Splintered Universe” Trilogy. Starfire World Syndicate / Pixl Press.

Robbins, Jim. 2012. “The Man Who Plants Trees”. Spiegel & Grau, New York. 256 pp.

Spracklen, Dominick V., Boris Bonn, and Kenneth S. Carslaw. 2008. “Boreal Forests, Aerosols and the Impacts on Clouds and Climate”. Phil. Trans. R. Soc. A 366: 4613–4626.

Wells, Nancy M. 2000. “At Home with Nature: Effects of ‘Greenness’ on Children’s Cognitive Functioning”. Environment and Behavior 32 (6): 775–795.


Water Is-pBook COVERThis article is an excerpt from Water Is…The Meaning of Water (Pixl Press), for sale worldwide May 10, 2016.





nina-2014aaNina Munteanu is an ecologist, limnologist and internationally published author of award-nominated speculative novels, short stories and non-fiction. She is co-editor of Europa SF and currently teaches writing courses at George Brown College and the University of Toronto. Visit for the latest on her books.

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