SEQUOIA, a genus of conifers (see GYMNOSPERMS) forming one of several surviving links between the firs and the cypresses.
The two species are evergreen trees of immense size, indigenous to the west coast of North Amer ica. Both bear their round or ovoid male catkins at the ends of the slender terminal branchlets; the ovoid cones, either terminal or on short lateral twigs, have thick woody scales dilated at the extremity, with a broad disk de pressed in the centre and usually furnished with a short spine ; at the base of the scales are from three to seven ovules, which be come reversed or partially so by compression, ripening into small angular seed with a narrow wing like expansion.
The redwood of the Calif or nian lumbermen, S. sempervirens, abounds on the Pacific coast from the southern borders of Oregon southward to Salmon Creek canyon, about 12 m. south of Punta Gorda, Monterey county, California, forming a narrow mountain forest belt, rarely extending more than 20 or 3o m. from the coast or beyond the influence of ocean fogs, or more than 3,00o ft. above sea-level. (See C. S. Sargent, Manual of the Trees of North America, 2nd ed., 1922.) It grows to a gigantic size, from 200 to 340 ft. in height, with a diameter of from 10 to 15, or even to 28 ft., at the much-buttressed base. It is the tallest American tree. In old age the huge columnar trunk rises to a great height bare of boughs, while on the upper part the branches are short and irregular.
The bark is red, like that of the Scots fir, deeply furrowed, with the ridges often much curved and twisted. When young the stem rises straight and tapering, with somewhat irregular whorls of drooping branches, the lower ones sweeping the ground— giving an elegant conical outline. The twigs are densely clothed with flat spreading linear leaves of a fine glossy green above and glaucous beneath ; in the old trees they become shorter and more rigid and partly lose their distichous habit. The cones, from 4 to I in. long, are at first of a bluish-green colour, but when mature change to a reddish brown; the scales are very small at the base, dilating into a broad thick head, with a short curved spine below the deep transverse depression. From the great size of the trunk
and the even grain of the red cedar-like wood it is a valuable tree: it splits readily and evenly, and planes and polishes well; cut radially, the medullary plates give the wood a fine satiny lustre; it is strong and durable, but not so elastic as many of the western pines and firs. Sargent describes it as the most valuable timber tree of the forests of Pacific North America. In England the tree grows well in warm situations, but suffers much in severe winters. It was discovered by Archibald Menzies in 1795 and was first described as Taxodium sempervirens, under which name it was known until distinguished by Stephan Endlicher as a new genus in The only other member of the genus is the giant sequoia or "big tree" of the Sierra Nevada, S. gigantea, the largest of known coniferi; it is confined to the western portion of the great Cali fornian range for a length of about 26o miles, at an altitude of from 5,000 to 8,400 ft. above the sea, and forms extensive forests, or, in the northern part of the area, isolated groves, such as the Calaveras grove, the Mariposa grove, and others. The leaves of this species are awl-shaped, short and rigid, with pointed apex; closely adpressed, they completely cover the branchlets. The young tree is more formal and rigid in growth than S. semper virens, but when old the outline of the head becomes cylindrical, with short branches sparsely clad with foliage sprays. The bark, of nearly the same tint as that of the redwood, is extremely thick and is channelled towards the base with vertical furrows ; at the root the ridges often stand out in buttress-like projections. The average height is about 275 ft. with a diameter near the ground of 20 ft.; but specimens from 30o to 32o ft. tall, with trunks 25-35 ft. thick, have been found.