States into two grand divisions, which may be called the Eastern and the Western forests. The Eastern forest is characterized by the predominance, on the whole, of broad-leafed trees, the comparative uniformity of its general types over wide areas, and its naturally unbroken distribution. In the Western forest conifers are conspicuously predominant; the individual species often reaches enormous and even unequalled dimensions, the forest is frequently interrupted by treeless areas, and the transitions from one type to another are often exceedingly abrupt. Both divisions are botanically and commercially rich in species.
The Eastern forest may conveniently be subdivided into three members:
1. The Northern forest, marked by great density and large volume of standing timber, and a comparative immunity, in its virgin condition, from fire. The characteristic trees are maples, birches and beech (Fagus atropunicea), among the hardwoods and white pine (Pinus strobus), spruce (Picea rubens and Picea mariana) and hemlock (Tsuga canadensis) among conifers.
2. The Southern forest is on the whole less dense than the Northern, and more frequently burned over. Among its characteristic trees are the longleaf (Pinus palustris) and other pines, oaks, gums, bald cypress (Taxodium distichum) and white cedar (Chamaecyparis thyoides).
3. The Central Hardwood forest, which differs comparatively little from adjacent portions of the Northern and Southern forests except in the absence of conifers. Among its trees are the chestnut (Castanea dentata), hickories, ashes and other hardwoods already mentioned.
The Western division has two members:
1. The Pacific Coast forest, marked by the great size of its trees and the vast accumulations of merchantable timber. Among its characteristic species are the redwood (Sequoia sempervirens) and the big tree (S. Washingtoniana), the Douglas fir (Pseudotsuga taxifolia), sugar pine (Pinus lambertiana), western hemlock (Tsuga heterophylla), giant arborvitae (Thuja plicata) and Sitka spruce (Picea sitchensis).
2. The Rocky Mountain forest, whose characteristic species are the western yellow pine (Pinus ponderosa), Engelmann spruce (Picea engelmanni) and lodgepole pine (Pinus murrayana). This forest is frequently broken by treeless areas of greater or less extent, especially towards the south, and it suffers greatly from fire. Subarid in character, except to the north and at high elevations, the vast mining interests of the region and its treeless surroundings give this forest an economic value out of proportion to the quantities of timber it contains.
This distribution of the various forests is indicated on the first of the two accompanying maps. The second map shows the situation of the national forests hereafter mentioned.
The forests of Alaska fall into two main divisions: the commercial though undeveloped forests of the south-east coast, which occur along the streams and on the lower slopes of the mountains and consist chiefly of western hemlock (Tsuga heterophylla), Sitka spruce (Picea sitchensis), yellow cedar (Chamaecyparis nootkatensis) and giant arborvitae (Thuja plicata), usually of large size and uninjured by fire; and the vast interior forests, swept by severe fires, and consisting chiefly of white and black spruces (Picea canadensis and nigra), paper birch (Betula papyrifera) and aspen (Populus tremuloides), all of small size but of great importance in connexion with mining. Northern Alaska and the extreme western coast regions are entirely barren.
The National Forest Policy.—The forest policy of the United States may be said to have had its origin in 1799 in the enactment of a law which authorized the purchase of timber suitable for the use of the navy, or of land upon which such timber was growing. It is true that laws were in force under the early governments of Massachusetts, New Jersey and other colonies, providing for the care and protection of forest interests in various ways, but these laws were distinctly survivals of tendencies acquired in Europe, and for the most part of little use. It was not until the apparent approach of a dangerous shortage in certain timber supplies that the first real step in forest policy was taken by the United States. Successive laws passed from 1817 to 1831 strove to give larger effect to the original enactment, but without permanent influence towards the preservation of the live oak (Quercus virginiana Mill.), which was the object in view. A long period of inaction followed these early measures. In
