‘Forest bathing’: spending time in the woods for its therapeutic (or bathing) effect — Breathe in phytoncides, active substances released by plants to protect them against insects and from rotting, which appear to lower blood pressure and stress and boost your immune system

From: mnn.com…

Forest bathing

The Japanese term Shinrin-yoku may literally mean “forest bathing,” but it doesn’t involve soaking in a tub among the trees. Rather it refers to spending time in the woods for its therapeutic (or bathing) effect. Most of us have felt tension slip away in the midst of trees and nature’s beauty. But science now confirms its healing influence on the body. When you spend a few hours on a woodland hike or camping by a lake you breathe in phytoncides, active substances released by plants to protect them against insects and from rotting, which appear to lower blood pressure and stress and boost your immune system.