The best time to plant a tree.
On a road trip through Japan, I was fortunate enough to visit the famed Arashiyama bamboo forest in Kyoto. It was one of the most serene and otherworldly places I experienced during my entire travels. It’s hard to describe the feeling of being surrounded by impossibly tall plants, gazing up at towering bamboo pillars that whisper gracefully in the wind. The peaceful beauty resonates deeply.
‘Shinrin-yoku’ is a form of therapy that originated in Japan, and it can be translated simply as ‘forest bathing’. Our general separation from nature and overloaded daily life clearly cause us stress, and it seems intuitive that we are soothed when we step away from our hectic routines and spend time surrounded by nature. However, the effects are not just psychological as research studies have established clear links with physiological benefits, from reducing blood pressure to boosting our immune system. These health benefits can last for several days, so returning regularly to shinrin-yoku has the potential to promote sustained wellbeing.
A new study published this month by University of Illinois found that Medicare costs tend to be lower in U.S. counties with more forests and shrub lands than in counties dominated by other types of land cover. The relationship persists even when accounting for economic, geographic or other factors that might independently influence health care costs. The study adds to a growing body of evidence in the USA, U.K. and many other countries, linking green space – especially forested areas – to better health outcomes for those living nearby.
How can forests deliver similar benefits to concrete-fatigued city dwellers? Vertical construction in dense urban areas has proven to be an efficient way of creating more homes and offices while keeping the footprint on the ground relatively small. This precedent has been applied in Milan, where the Milanese have expanded their green space by creating two ‘vertical forests’. Not far from the busy Garibaldi train station, a couple of residential tower blocks have been covered in eight hundred trees, five thousand shrubs and fifteen thousand plants. If all these plants were in the ground instead of in the sky, they would cover twenty thousand square metres.
Elsewhere, projects have been commissioned in Switzerland, the Netherlands and China, as other cities take up the lead. The most ambitious proposal is Chinese, where the Liuzhou Forest City will have seventy buildings cascading with foliage. This new town will be home to thirty thousand people, with buildings covered by forty thousand trees and one million plants. A forward-thinking city where trees outnumber people. These vertical forests are expected to absorb almost ten thousand tons of carbon dioxide and fifty-seven tons of pollutants per year.
Similar positive health effects can be achieved by visiting a local park or green space with trees, and also by keeping more plants inside buildings. Unfortunately, the connection between disengaged citizens and declining urban green space is all too common. In the USA for example, despite the strong evidence of the health and environmental benefits of urban trees for city residents, urban trees are steadily disappearing. According to The Nature Conservancy, around four million urban trees die or disappear each year without being replaced, even though studies quantify that every dollar spent on planting trees delivers almost six dollars in public benefits. Money is literally growing on trees and yet on average U.S. cities are still becoming less green.
What is needed is a fundamental shift in our collective attitude: from viewing urban trees as a nicety or useful in the gentrification of neighbourhoods, to seeing them as nothing less than public health infrastructure and crucial to climate change mitigation.
The best time to plant a tree is 20 years ago. The second best time is now.