Science and conservation In Japan it’s called shinrin-yoku, “forest bathing.” It’s the practice of taking in the atmosphere of the forest using all your senses, slowly and mindfully. Scientists have found that forest bathing can reduce levels of stress hormones in the body. Some studies have also suggested that phytoncides (natural chemicals released by trees) can boost the immune system. More generally, researchers have found that being in nature can improve mood, attention and problem-solving skills. Here are five walks that will let you experience different kinds of forest—and learn a bit about forest conservation along the way.