USING THIS BOOK   

Trees are the most conspicuous and best-known plants in man’s experience. Many are graceful and a joy to see. So it is no wonder that people want to know the different trees. This book is a guide to the most common trees in America. In addition to the 140 kinds pictured, the book may help you identify many more that are similar.

Most illustrations in this book show both the leaves of a tree and the form it usually takes as it grows. By studying the forms of trees, you may soon learn to identify them at a distance. This book deals only with trees. It does not include vines or shrubs. A tree is a woody plant that grows to a height of 10 feet or more. Most have a single erect stem. While shrubs also are woody, they are usually smaller than a tree and tend to have many stems growing in a clump.

This country has two major groups of trees: conifers (Pines and their relatives), identified by needle-like or scaly leaves; and the broad-leaved trees (leaves broad in contrast to leaves of the Pines). Some of the latter, like Willows, have narrow leaves. Others, like Maples, have broad ones. Trees with similar types of leaves have been placed together in this book to make identification easier.

One group of broad-leaved trees has simple leaves—leaves with a single, flattened blade on a stalk or petiole. Other trees have compound leaves, in which the blade is divided into a number of leaflets. A leaflet may look a good deal like a leaf, but leaflets are distinct in having no bud at their base.

The leaf blade may be entire; that is, with a smooth, uncut edge. The edge may be toothed, or it may have larger projections called lobes. Sometimes a leaf is both lobed and toothed. The pattern of the leaf edge permits further classification of trees—such as used here.

When you find a tree you do not know, first decide if it is a needle-leaf or a broad-leaf type. If the latter, see whether it is simple or compound, entire, or toothed or lobed. This you can tell at a glance. Then use the key to find where in this book the tree is likely to appear. Information in this book stresses identification.

Range maps show where various trees are likely to occur. If the range of more than one tree is given, a different color or line pattern is used for each. Overlapping of colors and lines means overlapping of ranges. Each species is named on, or near, the color or line pattern it refers to.

As you learn more about trees, knowledge of their scientific names grows increasingly useful. Scientific names of the trees illustrated in this book.

Slip this book into your pocket or pocketbook. Use it in the park or along the street whenever you see a tree you do not know. Thumb through the book in your spare time. Become familiar with common trees, so you recognize them at sight. At first you will have to check details of leaf, bark, and perhaps buds and fruit to be sure of your identification. As you come to know trees by their branching and their form, you will be able to identify some kinds at a distance. Other, less striking or less common trees will take closer looking.