"I hold trees in the highest regard; they represent age and beauty, the miracles of life and growth, and purify the air we breathe ."
You would be hard pressed to find a Children's classic that didn't involve trees somehow, even Pinocchio has a tree leave growing from his nose when he lies. Harry Potter has the Whomping Willow and J.R. Tolkein has the Ent. The Ent who figures most prominently in the book is Treebeard, who (credibly) claims to be the oldest creature in Middle-earth. There are many reasons why they figure so prominently in our lives.