I am mother and father, but never birth or nurse. I'm rarely still, but I never wander. What am I? The answer is a "tree".
Trees absorb carbon dioxide (a greenhouse gas) and give oxygen for people to breathe. Trees take in odors and pollutant gases (nitrogen oxides, ammonia, sulfur dioxide and ozone) and separate particulates out of the air by trapping them on their leaves and bark.
Studies have shown that patients with views of trees out their windows recover faster and with less complication. Children with ADHD show less symptoms when they have access to nature. Exposure to trees and nature improves concentration by lowering mental fatigue.
Of interest, according to The Guardian some of Britain's best-loved trees could be cloned in an effort to reproduce a range of our most successful and sturdy oaks, yews and firs. Find out more here.