In Part One of this series on trees, I talked about the benefits of drinking tree sap.
Amazingly, you don’t even need to drink the sap directly to benefit from the elixirs inside trees. Through the constant action of evapotranspiration, trees release an amazing number of aerosols, many of which are beneficial to all life.
Studies have also shown that different trees provide different benefits. A recent study by Lancaster University showed the birch tree’s detoxifying capabilities when they planted silver birch trees between a street of houses and a busy road.
According to Professor Barbara Maher, the trees absorbed more than 50 per cent of the particulate dust — linked to respiratory problems — from passing traffic, much more than other species, such as oak.
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.
Scientists in Germany and the UK demonstrated that trees create and release a myriad of 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, reflecting 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.
Beresford-Kroeger argues that trees help maintain the health of the natural world, given that 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.
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 explore this more in Part 3 of this series—Why I Love Trees: Part 3, Feeling Trees.
- Bartholomew, Alick. 2010. “The Spiritual Life of Water”. Park Street Press, Rochester Vermont. 338 pp.
- Beresford–Kroeger, Diana. 2003. “Arboretum America: A Philosophy of the Forest.” University of Michigan Regional. 214 pp.
- 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.
Nina 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 www.ninamunteanu.ca for the latest on her books.