The Encyclopedia Americana (1920)/Redwood of California

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REDWOOD OF CALIFORNIA, the great cypress-like forest tree (Sequoia sempervirens) of the Pacific Coast. It is of the same genus with the big trees (S. gigantea), botanically described under Sequoia; the latter occurs in scattered groups on the west slope of the Sierra Nevada, while the redwood forms dense forests on the west slopes of the Coast Range, where it forms the most important timber resource of the State. The forests were thoroughly studied by the government bureau of forestry in 1902, whose report furnishes the following facts: The redwood is popularly thought to occupy a strip of country 10 to 30 miles wide, from the Oregon line to the Bay of Monterey, but these boundaries do not cover its actual distribution. Two thousand acres of redwood exist in Oregon along the Chetco River. South of the Chetco a continuous redwood belt begins, and increases its width from 10 miles, at Del Norte County, to 18 or 20 miles, and keeps on unbroken to southern Humboldt County. Here is a break, but in Mendocino County the belt becomes dense again, and widens out to 35 miles. South of that county the tree grows in isolated patches as far south as the Santa Lucia Mountains.

The climate and topography that have brought about this limited distribution of the redwood deserve attention. North and south along the coast, in nearly parallel ridges, lie the mountains of the Coast Range, steep and rising to altitudes of 1,000 to 2,000 feet. A few large rivers and many smaller streams cut through them to enter the sea, and along their courses in places are broad bottom lands and gentle slopes. West of the Coast Range the climate is even and moderate, with a range from just below freezing to 80° F., and a yearly average of from 50° to 60°. Snow lies on the tops of only the highest ridges. Thirty to 60 inches of rain falls in the autumn and winter, and in the summer sea fog bathes the coast. But east of the mountains, less than 50 miles from the sea, lie hot interior valleys, never visited by the fog, parched and rainless in the summer, and wet only occasionally by the winter rains — conditions too unfavorable to permit the growth of the redwood. The forest may be considered in two types — the “slope” and the “flat.” The common type is the “slope” — that is, the growth on the steep sides of the Coast Range, which is a mixture of redwood, red fir, tanbark oak and white fir, with an occasional madroña or hemlock. As the slopes become moderate, the altitude lower, the soil deeper and the water supply better, the redwood steadily gains on the other kinds and the forest becomes denser, until on the rich flats and in the gulches the second type is developed; on the best redwood “flats” no other tree grows.

The redwood grows to a greater height than any other American tree, but in girth and in age it is exceeded by the big trees of the Sierras. On the slopes 225 feet is about the maximum height and 10 feet its greatest diameter, while on the flats, under better conditions, it grows to be 350 feet high, with a diameter of 20 feet, and occasional giants exceed this. Most of the redwoods cut are from 400 to 800 years old. After the tree has passed the age of 500 years it usually begins to die down from the top and to fall off in growth. The oldest tree scientifically examined began life 531 A. D. The tree, when normal, has a straight, slightly tapered bole, clear for more than 100 feet, and a crown of horizontal branches that may occupy from a third to a half of its total length. The roots strike downward at a sharp angle, and are so large and so numerous as to form a compact mass of wood, in shape like an inverted funnel. The bark of the tree offers such a remarkable resistance to fire that except under great heat it is not combustible. It is of a reddish-gray color, fibrous in texture, and gives to full-grown trees a fluted appearance. The tree, however, assumes many shapes.

The redwood requires little of the soil except that it be moist, and those trees in a gully or along a creek are larger than their neighbors on the ridges. It is, however, so dependent on moisture of the air that this factor mainly or wholly determines its distribution, and the eastern limits of the forests are determined by the distance inland to which the sea fogs may drift.

The enemies of the redwood are few, and it suffers from them less than other trees. “The wind,” remarks Fisher, “can scarcely uproot it, insects seem to do it little harm, and fungi seldom affect it. Even fire, the great enemy of all trees, though it may occasionally kill whole stands of young redwood growth, is unable to penetrate the fireproof sheathing of shaggy bark with which the old trees protect themselves.” A large area of redwood forest in Santa Cruz County has been reserved as a national forest-park.

Reproduction. — The redwood forest consists of a mixture of trees of widely varying type, and keeps itself stocked by reproduction under its own shade. Seeds grow up very seldom, the seed itself seeming to have little vitality and the opportunities for its germination being rarely present, because it demands plentiful light. Hence new growth is almost exclusively by suckers, which supported and nourished by full-grown roots and stems, thrive under shade in which seedlings would wither. They thus survive and grow slowly, with little or no sun, until an old tree falls, lets in the light and they shoot up in rings about the stump into strong young trees. In 30 years, under favorable conditions, trees will result 16 inches in diameter and 80 feet high; and it is certain that it will be profitable to hold cut-over redwood lands for future crops. This second-growth timber has not the density and fine quality of the original, but is useful for many purposes, and large quantities have already been utilized.

Quality of the Wood. — Redwood is fitted for many uses. In color it shades from light cherry to dark mahogany; its grain is usually straight, fine and even; its weight is light; its consistency firm; yet soft. It is easily worked, takes a beautiful polish and is the most durable of the coniferous woods of California. It resists decay so well that trees which have lain 500 years in the forest have been sent to the mill and sawed into lumber. It has no resin, and resists fire, a fact which has recommended it as material for house-building, especially in San Francisco. Insects seldom injure it, because of an acid element its lumber contains. In sea water, however, the marine teredo eats off redwood piling as readily as other timber. Redwood is used for all kinds of finishing and construction for shingles, railroad ties, electric-light poles, paving blocks, tanks and pipe staves. As a tie its average life, under heavy traffic, is six to eight years; as shingles it will last as long as 40 years. The chief difficulty in working redwood lies in the seasoning process, to dry it thoroughly being a slow and difficult process.

Lumbering. — The cutting of redwood for market began about 1850, and has steadily increased since with the market demand and growth of means of transportation. Its use is mainly confined to the State, and the greatest demand is from the southern counties. Occasional cargoes are sent across the Pacific, but it is rarely sent East, on account of the expense of transportation. It has never been a business giving extravagant profits. Several hundred thousand acres have already been cut over. A large part of this area has been completely cleared and cultivated or used for pasture but much remains as wild brush, believed to be useless; but it is now known that ordinarily a profitable second growth will arise, so that the anticipated extinction of the tree is no longer to be feared.

Felling one of these enormous trees is an operation requiring great experience and skill on the part of the woodsman, who must cause the vast trunk to fall precisely where he intends it to lie, and must take care that it is not split or broken by the concussion, to prevent which a bed is smoothed and prepared for it. A platform is first erected surrounding the trunk from six to eight feet above the ground. With a long saw in the hands of two men an undercut is made through the trunk, not quite to the centre, and from the opposite side a crosscut is sawed, ending a foot or two above the undercut and leaving a section of solid wood between. When the exact place where the tree is to fall is selected, the choppers ascend the platform and with axes hew out an angular-shaped piece having the undercut as a base. When this cut is made the second or crosscut is wedged till the tree topples over and falls to the ground, the solid section of the trunk, not pierced by the cuts, supporting the tree till the centre of gravity is passed, and then the mighty frame falls on its prepared bed almost intact.

The next operation is performed by the “ringers” and “peelers.” Every 12 or 14 feet, as required, a ring is cut around the circumference of the bark, and afterward the peelers with crowbars and wedges "peel" the bark from the prostrate trunk. All of the trees are stripped but surrounded with an immense accumulation of debris of bark and branches, which must be removed before the trunks can be sawed into suitable lengths for conveyance to the mill. The ground is cleared of this debris by fire, precaution being first taken to plug up the “splits” in the trunk with clay so that the fire may not reach the interior of the tree. A foggy day is chosen and a still one. Fire is started and in a short time the tract is burning with a fierce heat that quickly reduces the piles of bark and brush to ashes, and leaves an unobstructed field for the removal of the solid timber which has been scarcely charred by the intense heat to which it has been subjected.

The trunks as they lie are then sawed into stated lengths, and then follows the arduous task of conveying these enormously heavy sections to the railroad. Temporary skidways are laid down and roads constructed. Chutes down which the logs pass have to be planned, and on these, guided by the skilful woodsmen, the unwieldy logs at last reach their destination. The work is assisted by donkey engines on sleds, which are hauled to the top of the steep banks and into seemingly impossible situations.

The yield of virgin redwoods on the northern flats varies from 125,000 to 150,000 board feet per acre. About Humboldt Bay it was from 50,000 to 75,000 feet per acre; and on slopes like those in Sonoma County, from 20,900 to 30,000 feet. The redwood cut of 1916 was 491,000,000, the largest recorded, being about 35 per cent of the entire lumber cut of the State. The amount of timber got out of a redwood forest is only a small proportion of what the stand contained. At least a quarter of the timber is destroyed in felling and in the burning that follows, and of what remains all the broken and misshapen logs are left on the ground.

Bibliography. — Fisher, ‘Report on Redwood,’ Bureau of Forestry (Washington 1903); and authorities on California, especially Muir, and on forestry. See Forestry.