Studies of Trees

by Jacob Joshua Levison

Educators and parents are now recognizing the value of outdoor trips for their children and are beginning to indulge in them quite frequently. In many instances teachers about to take out their children for a day have inquired of the writer how to go about giving a general field lesson when they reached the park or woodland. The purpose of this chapter is to answer such a question and yet it is evident that it cannot be answered completely. What to observe out doors and how to present one’s impressions is a broad question and varies with the knowledge and ability of the teacher as well as with the age and experience of the children. The how and the what in nature study is of greater import than the hard, dry facts and that must be left entirely to the teacher. A few suggestions, however, may not be amiss:

1. General observations with a view to character building: First of all it is important to remember that the great value of all tree and nature study is the inculcation in the minds of the children of an appreciation and love for the beautiful. Inspiring them to love trees generally means more than teaching them to know trees. Mere facts about trees taught in an academic way are often no more lasting than the formulæ in trigonometry which most of us have long ago forgotten. The important thing is that permanent results be left and nothing else will produce such lasting impressions as the study of trees out of doors.

Fig. 153.—Trees Have Individuality.

General observations about trees can be made by pointing out the beauty and character of the individual forms and branching, their harmony in their relations to each other as factors of a beautiful composition and the wealth of shades and colors in their leaves, bark and flowers. Compare, for instance, the intricate ramification of an American elm with the simple branching of a sugar maple, the sturdiness of a white oak with the tenderness of a soft maple, the wide spread of a beech with the slender form of a Lombardy poplar, the upward pointing branches of a gingko with the drooping form of a weeping willow. At close range, each of these trees reveals itself as an individual with a character quite its own. At little distance you may see them grouped together, subordinating their individuality and helping to blend into a beautiful composition with a character all its own. There is nothing more inspiring than the variety of greens in the spring foliage, the diversity of color in the spring blossoms and the wonderful display of autumnal tints offered by the sweet gum, sassafras, dogwood, black gum, red maple, sugar maple, scarlet oak, blue beech, sorrel tree, ash and gingko. The white bark of the gray birch, the dark bark of the black oak, the gray of the beech, the golden yellow of the mulberry and the mottled bark of the sycamore are interesting comparisons. The smooth bark of the mockernut hickory contrasts greatly with the shaggy bark of the shagbark hickory—members of the same family and yet how different. A wonderful opportunity is thus offered for a comparative study of human nature—individuality and community life, all reflected in trees.

With this preliminary study and with the addition of some remarks on the value of trees as health givers and moral uplifters, the child is interested and attracted. The lesson so far has attained its aim.

2. Specific observations with a view to training the observative powers: The child’s training in closeness of observation and scientific precision may be the next consideration. His enthusiasm will now prompt him to lend his interest for greater detail. We can teach him to recognize a few of the common trees by their general characters—an American elm by its fan-shaped form, a gray birch by its white bark, a white pine by the five needles to each cluster, a horsechestnut by its opposite branching and big sticky bud and a willow by its drooping habit. After that we may introduce, if the age of the pupils justifies, more details extending to greater differences which distinguish one species from another.

The lesson might continue by pointing out the requirements of trees for water and light. Find a tree on some slope where the roots are exposed and another which is being encroached upon by its neighbor, and show how in one case the roots travel in search of water and food and in the other the branches bend toward the light, growing more vigorously on that side. Compare the trees on the open lawn with those in the grove and show how those in the open have grown with branches near the ground while those in the woodland are slender, tall and free from branches to some distance above the ground. Point out the lenticels on the bark of birch and sweet cherry trees and explain how trees breathe. Compare this process with that of the human body. You may now come across an old stump and here you can point out the structure of the wood—the sapwood, cambium and bark. You can illustrate the annual rings and count the age of the tree. At another point you may find a tree with a wound or bruised bark and here you can readily make a closer study of the cambium layer and its manner of growth.

The adaptation of plants to the seasonal changes opens another interesting field of study for beginners. If the season is the fall or winter, note how the trees have prepared themselves for the winter’s cold by terminating the flow of sap, by dropping their leaves too tender to resist the winter’s cold, and by covering their buds with scales lined with down on the inside. Observe how the insects have spun for themselves silken nests or remain preserved in the egg state over the winter. If the season is spring or summer the opposite may be noted. See how everything turns to life; how the buds are opening, the leaves emerging, the sap running, seeds germinating and flowers blooming.