INTRODUCTORY. There are two points of view from which to regard trees--the mercantile and the aesthetic. The former is well exemplified in Dumbiedyke's advice to Jock: "Jock, when ye hae naething else to do, ye may be aye sticking in a tree; it will be growing, Jock, when ye're sleeping." The canny Scot was thinking of the "unearned increment" another generation might gather in, due to the almost unceasing activity of the vegetable cells in the manufacture of timber. The other view was expressed by "the Autocrat of the Breakfast-table" in a letter to a friend: "Whenever we plant a tree we are doing what we can to make our planet a more wholesome and happier dwelling-place for those who come after us, if not for ourselves." But, after all, it is the trees that have been planted by Nature that give the greatest pleasure apart from commercial considerations--the lonely Pine, that grows in rugged grandeur on the edge of the escarpment where its seed was planted in the crevice by the wind; the Oak that grows outside the forest, where a squirrel or a jay dropped the acorn, and where the young tree had room all its life to throw out its arms as it would; the little cluster of Birches that springs from the ferns and moss of the hillside. All trees so grown develop an individuality that is not apparent in their fellows of the timber forest; and however we may delight in the peace and quiet of the forest, with its softened light and cool fragrant air, we can there only regard the trees in a mass. We might, indeed, reverse the old saying, and declare that we cannot see the trees on account of the wood.