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Fostering Sustainable Agriculture through Research, Education and Policy since 1984

What is the secret power of trees that makes us so much healthier and happier?

Dr. Qing Li, Chairman of the Japanese Society for Forest Medicine and Professor at the Nippon Medical School in Tokyo, is studying this tree-human relationship; the Japanese art and science of shinrin-yoku, or Forest Bathing.

“We all know how good being in nature can make us feel. We have known it for millennia. The sounds of the forest, the scent of the trees, the sunlight playing through the leaves, the fresh, clean air – these things give us a sense of comfort. They ease our stress and worry, help us relax and to think more clearly. Being in nature can restore our mood, give us back our energy and vitality, refresh and rejuvenate us. “ Dr. Qing Li, Forest Bathing

In his book, Forest Bathing, Dr. Li takes us on a journey to discovering what has been learned about trees, how we can up their power, and that wherever there are trees, we are happier and healthier. I have always had an instinctual feeling about the beneficial properties of trees and nature, however I learned some new things in this book.

One is that several “studies suggest that we can raise our natural killer cell activity just by going for a walk in nature.” The studies also found that “people who live in areas with fewer trees not only have significantly higher levels of stress and depression, they also have higher mortality rates than people who live where there is a good density of trees.” P. 87

Another is that “the positive effect of tress on people’s mental well-being last longer than short-term boosts to happiness, such as a pay rise or getting married.” p. 115-116

Also, rubber soled shoes insulate us from the ground, “they block the flow of electrons and break the connection with the earth that helps our bodies to function properly. Some people have called shoes one of the most dangerous inventions of mankind and maintain that walking barefoot is the way we are meant to get around.” p.209

A study found “there are around 3.04 trillion trees on earth. That’s around 400 for each person on the planet. 15 billion are lost every year – or around 2 trees per person. That’s a lot of trees. In fact, we’ve nearly halved the amount of trees on the planet. … Our health and the health of the forest go hand in hand.” p. 277-278 One of the biggest ‘natural experiments’ on the relationship between trees and human health was carried out as a result of the emerald ash borer disease in America, over 100 million trees have died so far. The US Forest Service found that, in the places where trees had been affected by the disease, mortality rates were higher… the greater the infestation, the greater its effect on human health.” p. 113-115

The tree mapping tool, iTree, “maps the monetary value of the ‘eco services’ that trees provide – the carbon they store, the pollution they remove, the amount of storm-water run-off they reduce. … it calculated that the 8.4 million trees in London provide 133 million euro in benefits each year. The US Forest Service has calculated that trees in American cities remove $3.8 billion worth of air pollution, prevent 670,000 incidents of acute respiratory symptoms and save 850 lives per year. Figures from Washington DC show that the amount of pollution trees remove in the city is the equivalent of taking 274,000 cars off the roads.”

Enjoy a walk, plant a tree, and learn lots more about the beneficial properties of trees in this book.