Leaving the relations which trees hold to the animals about them and the part which they have played in the evolution of life on the earth in past epochs, let us consider some of the more humble trees about us. Not, however, from the standpoint of the technical botanist or the scientific forester, but from the sympathetic point of view of a living fellow form, sharing the same planet, both owing their lives to the same great source of all light and heat, and subject to the same extremes of heat and cold, storm and drought. How wonderful, when we come to think of it, is a tree, to be able to withstand its enemies, elemental and animate, year after year, decade after decade, although fast-rooted to one patch of earth. An animal flees to shelter at the approach of gale or cyclone, or travels far in search of abundant food. Like the giant algae, ever waving upward from the bed of the sea, which depend on the nourishment of the surrounding waters, so the tree blindly trusts to Nature to minister to its needs, filling its leaves with the light-given greenness, and feeling for nutritious salts with the sensitive tips of its innumerable rootlets. Darwin has taught us, and truly, that a relentless struggle for existence is ever going on around us, and although this is most evident to our eyes in a terrible death battle between two great beasts of prey, yet it is no less real and intense in the case of the bird pouring forth a beautiful song, or the delicate violet shedding abroad its perfume. To realise the host of enemies ever shadowing the feathered songster and its kind, we have only to remember that though four young birds may be hatched in each of fifty nests, yet of the two hundred nestlings an average often of but one lives to grow to maturity,--to migrate and to return to the region of its birth. And the violet, living, apparently, such a quiet life of humble sweetness? Fortunate indeed is it if its tiny treasure of seeds is fertilized, and then the chances are a thousand to one that they will grow and ripen only to fall by the wayside, or on barren ground, or among the tares. At first thought, a tree seems far removed from all such struggles. How solemn and grand its trunk stands, column-like against the sky! How puny and weak we seem beside it! Its sturdy roots, sound wood, and pliant branches all spell power. Nevertheless, the old, old struggle is as fierce, as unending, here as everywhere. A monarch of the forest has gained its supremacy only by a lifelong battle with its own kind and with a horde of alien enemies. From the heart of the tropics to the limit of tree-growth in the northland we find the battle of life waged fiercely, root contending with root for earth-food, branch with branch for the light which means life.