Kevin Wade created a typography style inspired by tree trunks, named Ringbearer. When trying to sell the text, he decided he needed a new way of displaying it and with that came the tree ring book.
The book by Kevin Wade features individual letters of his typography on separate pages, all made to look like rings of a tree. At the end of the book is a fold out poster that shows all the text. A great way to sell an idea, and in this case, a tree-inspired text.