Studies of Trees

CHAPTER IX. An Outdoor Lesson on Trees

AN OUTDOOR LESSON ON TREES

INTRODUCTION

A good many popular books on trees have been published in the United States in recent years. The continually increasing demand for books of this character indicates the growing public interest not only in the trees that we pass in our daily walks, but also in the forest considered as a community of trees, because of its aesthetic and protective value and its usefulness as a source of important economic products.

As a nation, we are thinking more about trees and woods than we were wont to do in the years gone by. We are growing to love the trees and forests as we turn more and more to outdoor life for recreation and sport. In our ramblings along shady streets, through grassy parks, over wooded valleys, and in mountain wildernesses we find that much more than formerly we are asking ourselves what are these trees, what are the leaf, flower, twig, wood and habit characteristics which distinguish them from other trees; how large do they grow; under what conditions of soil and climate do they thrive best; what are their enemies and how can they be overcome; what is their value for wood and other useful products; what is their protective value; are they useful for planting along streets and in parks and in regenerating forests; how can the trees of our streets and lawns be preserved and repaired as they begin to fail from old age or other causes? All these questions and many more relating to the important native and exotic trees commonly found in the states east of the Great Lakes and north of Maryland Mr. Levison has briefly answered in this book. The author's training as a forester and his experience as a professional arboriculturist has peculiarly fitted him to speak in an authoritative and interesting way about trees and woods.

The value of this book is not in new knowledge, but in the simple statement of the most important facts relating to some of our common trees, individually and collectively considered. A knowledge of trees and forests adds vastly to the pleasures of outdoor life. The more we study trees and the more intimate our knowledge of the forest as a unit of vegetation in which each tree, each flower, each animal and insect has its part to play in the complete structure, the greater will be our admiration of the wonderful beauty and variety exhibited in the trees and woods about us.

J.W. TOUMEY, Director, Yale University Forest School.

NEW HAVEN, CONN., June, 1914.

STUDIES OF TREES

CHAPTER I. How to Identify Trees

HOW TO IDENTIFY TREES

There are many ways in which the problem of identifying trees may be approached. The majority attempt to recognize trees by their leaf characters. Leaf characters, however, do not differentiate the trees during the other half of the year when they are bare. In this chapter the characterizations are based, as far as possible, on peculiarities that are evident all year round. In almost every tree there is some one trait that marks its individuality and separates it, at a glance, from all other trees. It may be the general form of the tree, its mode of branching, bark, bud or fruit. It may be some variation in color, or, in case of the evergreen trees, it may be the number and position of the needles or leaves. The species included in the following pages have thus been arranged in groups based on these permanent characters. The individual species are further described by a distinguishing paragraph in which the main character of the tree is emphasized in heavy type.

The last paragraph under each species is also important because it classifies all related species and distinguishes those that are liable to be confused with the particular tree under consideration.

GROUP I. THE PINES

How to tell them from other trees: The pines belong to the coniferous class of trees; that is, trees which bear cones. The pines may be told from the other coniferous trees by their leaves, which are in the form of needles two inches or more in length. These needles keep green throughout the entire year. This is characteristic of all coniferous trees, except the larch and cypress, which shed their leaves in winter.

The pines are widely distributed throughout the Northern Hemisphere, and include about 80 distinct species with over 600 varieties. The species enumerated here are especially common in the eastern part of the United states, growing either native in the forest or under cultivation in the parks. The pines form a very important class of timber trees, and produce beautiful effects when planted in groups in the parks.

How to tell them from each other: The pine needles are arranged in clusters; see Fig. 1. Each species has a certain characteristic number of needles to the cluster and this fact generally provides the simplest and most direct way of distinguishing the different pines.

In the white pine there are five needles to each cluster, in the pitch pine three, and in the Scotch pine two. The Austrian pine also has two needles to the cluster, but the difference in size and character of the needles will distinguish this species from the Scotch pine.

THE WHITE PINE (Pinus strobus)

Distinguishing characters: The tree can be told at close range by the number of needles to each cluster, Fig. 2. There are *five* needles to each cluster of the white pine. They are bluish green, slender, and about four inches in length.

At a distance the tree may be told by the *right angles* which the branches form with the main trunk, Fig. 3. No other pine shows this character.

Form and size: A tall tree, the stateliest of the evergreens.

Range: Eastern North America.

Soil and location: Prefers a deep, sandy soil, but will grow in almost any soil.

Enemies: Sucking insects forming white downy patches on the bark and twigs, the white pine weevil, a boring insect, and the white pine blister rust, a fungus, are among its principal enemies.

Value for planting: Aside from its value as an ornamental tree, the white pine is an excellent tree to plant on abandoned farms and for woodlands and windbreaks throughout the New England States, New York, Pennsylvania, and the Lake States.

Commercial value: The wood is easily worked, light, durable, and will not warp. It is used for naval construction, lumber, shingles, laths, interior finish, wooden ware, etc.

Other characters: The fruit is a cone, four to six inches long.

Comparisons: The tree is apt to be confused with the Bhotan pine (Pinus excelsa), which is commonly grown as an ornamental tree. The Bhotan pine, however, has needles much longer and more drooping in appearance.

THE PITCH PINE (Pinus rigida)

Distinguishing characters: Here there are *three* needles to each cluster, Fig. 4. They are dark, yellowish-green needles about four inches long. The rough-looking branches of the tree may be seen studded with cones throughout the year, and clusters of leaves may be seen sprouting directly from the trunk of the tree; see Fig. 5. The last two are very characteristic and will distinguish the tree at a glance.

Form and size: It is a low tree of uncertain habit and extremely rough looking at every stage of its life. It is constantly full of dead branches and old cones which persist on the tree throughout the year.

Range: Eastern United States.

Soil and location: Grows in the poorest and sandiest soils where few other trees will grow. In New Jersey and on Long Island where it is native, it proves so hardy and persistent that it often forms pure stands excluding other trees.

Enemies: None of importance.

Value for planting: Well adapted for the sea coast and other exposed places. It is of extremely uncertain habit and is subject to the loss of the lower limbs. It frequently presents a certain picturesqueness of outline, but it could not be used as a specimen tree on the lawn.

Commercial value: The wood is coarse grained and is used for rough lumber, fuel, and charcoal.

Other characters: The fruit is a cone one to three inches long, persistent on the tree for several years.

THE SCOTCH PINE (Pinus sylvestris)

Distinguishing characters: There are *two* needles to each cluster, and these are short compared with those of the white pine, and slightly twisted; see Fig. 6. The bark, especially along the upper portion of the trunk, is reddish in color.

Form and size: A medium-sized tree with a short crown.

Range: Europe, Asia, and eastern United States.

Soil and location: Will do best on a deep, rich, sandy soil, but will also grow on a dry, porous soil.

Enemies: In Europe the Scotch pine has several insect enemies, but in America it appears to be free from injury.

Value for planting: Suitable for windbreaks and woodland planting. Many excellent specimens may also be found in our parks.

Commercial value: In the United States, the wood is chiefly used for fuel, though slightly used for barrels, boxes, and carpentry. In Europe, the Scotch pine is an important timber tree.

Continue reading Studies of Trees free in the Wunder reader →