summit-peaks and ridges. In the Great Basin region, and from there southward, many of the mountains are practically destitute of trees from base to summit.
So vast is the region occupied by the Pacific forest and so varied the conditions dependent upon climate, soil, and elevation which influence its growth, that great variations in the genera and species of trees composing it are to be expected. This prediction is soon verified when one travels through the forest. The extremes may be indicated briefly by referring to the fact that at the north the trees are mainly spruces, firs, and cedars, and at the south include the giant cactus, arboreal yucca, and the fan-leafed palm. In its medial division are the great forests of western Washington and Oregon, composed mainly of firs and cedars, and the no less magnificent forests of redwood-trees on the Coast Ranges of northern California and the west slope of the Sierra Nevada. Like the boreal forest, the one under consideration is largely composed of coniferous trees, although in the valley, and especially along the borders of streams in southern Canada, Washington, etc., a few species of broad-leaved trees, such as the maple, cottonwood, ash, and alder, thrive in close association with dark conifers; while in similar situations farther south oaks growing in scattered groves give a park-like character to the land, as in the southern portion of California.
In contrast with the Atlantic region, the western portion of the continental forest belt is singularly lacking in broad-leaved trees, and such as are found are usually of small size and but little economic importance. This lack, however, is perhaps more than counterbalanced by the number both of individuals and of species and the great size and magnificence of the conifers.
One of the densest and in many ways most thoroughly representative portions of the Pacific forest where it occupies an excessively humid region occurs on the west side of the Cascade Mountains in Washington, inclusive of the Puget Sound basin and the region to the westward from which rise the Olympic Mountains.
In western Washington the forest is composed mainly,
and, in fact, over large areas, almost entirely of two species of trees, namely, the red fir and the red cedar, each of which attains gigantic dimensions. Of these two species, the first is the more common, the larger, and by far the more important from a commercial point of view. It frequently, and, in fact, commonly, attains a height of from 200 to 300 feet, with a diameter at the base of from 8 to 10 or more feet. Not only do these magnificent trees reach such great dimensions, but they are thickly set over hundreds of square miles of territory. In thousands of instances the great trunks sheathed in rough thick bark rise straight and massive, with but a slight decrease in diameter, to a height of upward of 80 feet before the first branch is given off. The cedars, the intimate companions of the great firs, are of equally gigantic girth at the base, but taper rapidly to spire-like summits, usually from 100 to 150 feet above the ground, and are thickly set with small branches throughout. They flourish best in excessively moist situations and reach far up the mountains, particularly along the numerous watercourses; while the firs, although perhaps most at home on the less thoroughly water-soaked uplands, thrive on the banks of streams, the sides and summits of hills, and on steep mountainsides alike.
Mere enumeration of the number and size of the trees, however, fails to give an adequate impression of the astonishing magnificence of the wonderful forest of the Puget Sound region. Its grandeur is beyond description, and can only be fully appreciated by one who abides for weeks or months in its perpetual twilight. The great trees, shaggy with mosses and lichens of innumerable tints of brown, green, and yellow, do not form detached groves, as is so frequently the case in less humid lands, but are thickly set for mile after mile and league after league, as one threads his difficult way beneath them. So vast is the forest that a person travelling through it soon becomes impressed with the idea that it is interminable. Beneath the deep shade of the lofty boughs there is a rank undergrowth of young firs, cedars, and hemlocks, while in the
valleys especially, and on the frequently inundated flood-plains of the streams, there is usually a tangled growth of vine-like maples, alders, elders, yews, etc. In this lower forest the most conspicuous and frequently too abundant plant is the broad-leaved and excessively spiny devil's-club, the foliage of which changes to brilliant yellow in the early autumn, and forms a most artistic setting for the spikes of crimson fruit borne at the extremities of the upward-bending ends of the usually prostrate stems.
