I first came across an older version of this book in 2000 or 2001. I was taking a botany course at Western Kentucky University (as part of my biology degree), and we used this for some of our field days. I remember thinking how great this book was at the time, and just last month my wife bought this for me. It is an updated version, and it is even better than the one I used.
From the publisher:
The Arbor Day Foundation's What Tree Is That? is a unique field guide that uses a step-by-step approach to identify common trees of the United States and Canada. The fully illustrated, 164-page book helps readers recognize more than 250 varieties based on trunk bark, leaf margins and textures, pods, nuts, and the arrangement of leaves on twigs.
Focusing on specific characteristics, this easy-to-use field guide poses a series of questions paired with botanical illustrations to help classify the tree in question. Created by the world's largest nonprofit devoted to trees and the environment, this guide offers a proven classification method for people of all ages--from youth to adult, amateur to professional.
The guide is a practical educational tool containing both the common and scientific names of trees and measurements in both inches and centimeters. Equipped with a durable, water-resistant cover, this 8½ x 4-inch companion guide slips easily into a pocket for easy reference on hikes.
I highly recommend this easy to use tree-identification guide book. Fantastic!