A knowledge of trees, the ability at least to recognize and identify them, adds vastly to the pleasures of life. One who knows trees well meets them like old friends; each season invests them with fresh charm, and the more we study and know them the greater will be our admiration of the wonderful variety and beauty which they display in winter. C. S. SARGENT. ARNOLD ARBORETUM, November, 1901. CHAPTER I THE STUDY OF TREES IN WINTER Chapter I THE STUDY OF TREES IN WINTER Outside my window the trees in a little wood stand leafless. Everything which made this wood a delight in June, the contrast of light and shade among the leaves, the varying tones of green in broken sunlight, the warmth and color and summer freshness, has gone, but the trees themselves, in all their wealth of foliage were never so beautiful as now. The massive moulding of their trunks, the graceful curves of their branches, the fine tracery of their little bare twigs, now clear against the sky and again lost in a tangled network of intersecting branches,—the whole beauty of their symmetry, their poise, strength, and delicacy is revealed as it is never revealed in summer. Attracted first by the obvious grace of the forms of trees as we see them from our windows in winter, we discover that a closer study of the details of bare twigs and buds in the woods discloses unsuspected beauty in texture, form, and color. Each tree has definite traits of its own which distinguish it from every other tree, and by tracing individual characteristics in the branches, trunk, stems, buds, and leaf-scars we are able to identify every tree with certainty. [Sidenote: Trunk and Branches] By observing the shapes and general outlines of trees in winter we are able to recognize them at a distance. This study of tree forms adds much to the pleasure of a railroad journey or a winter’s drive in the country, and accuracy is acquired by constant practice when we walk in the woods and fields and can verify the name of each tree. In this way we become familiar with the common trees, and learn to know the predominating trees of the forests through which we pass, often recognizing a rare species the distance of a field away. [Illustration: TREE WITH A DELIQUESCENT TRUNK] [Illustration: Cross section of a tree trunk, showing the rings of annual growth, the medullary rays, the dark heartwood, the lighter sapwood and the bark.] There are two distinct plans of branching in trees. When the main trunk extends upward to the tip, as it does in the larch and other conical trees, it is said to be _excurrent_, and when the main stem divides into many more or less equal divisions, as we find it in the American elm and other spreading trees, it is said to be _deliquescent_,—the latter form is the most common one among our deciduous trees. [Illustration: TREE WITH AN EXCURRENT TRUNK]