Trees have a profound, positive impact on our mental health, and research has made that clear. It has been proven that spending time among trees lowers cortisol levels. And simply living within 100 meters (about 300 feet) of a tree reduces rates of depression.
More recently, science has uncovered another way tree planting affects our mood and mental health: digging in the dirt. In addition to benefits that fresh air, physical exertion, and natural beauty provide, Mycobacterium vaccae — a microbe naturally found in soil — is also improving people’s temperaments.
This microbe’s primary role is to help break down organic matter like decaying leaves and needles, for example, but it can also increase brain serotonin, which can produce antidepressant-like effects in humans. This happens when people are merely working in the soil — tree planting included.
Researchers are still actively studying this phenomenon. While there are many working hypotheses as to why this happens, the amazing thing is that it does happen.
“We should all be really excited about that, and we should not underestimate the power of nature,” said Dr. Christopher Lowry, a professor at the University of Colorado Boulder and prominent researcher of this bacteria.
Get Your Daily Dose of Happy
If you want to experience this science at work for yourself, it’s as simple as grabbing a shovel and planting a tree. The cooler months in late fall are a great time to add a tree to your landscaping. Find out more about the benefits of fall planting at arborday.org/fall.