Cork tree

“ American zone was all that could be desired for the favorable rearing of cork trees; but strange to say this was not the case. Although the growth of the tree had been exceptionally strong, the quality of its salient product turned out to be of an inferior character. The cork generally improves with the age of the tree; in this instance, however, even after years of maturity the cork harvest did not improve to any great extent, and indeed is still of a second-rate quality. ”

“ The cork tree has in no wise escaped from disease and infections; on the contrary it has its full allotted share which worries the growers more than the acquiring of a perfect texture, and unless great care is taken will greatly reduce the value of a crop. ”

“ At one time it was supposed that the cork tree required no culture. But of late years great pains have been taken with it, and it readily responds to them. A self-sown tree growing up in the midst of heather and cistus is not likely to attain to a great size. ”

“ Unfortunately, the herds in foraging for food destroy the young trees and thus do serious and permanent injury by preventing new growth.
The “corkwood,” or cork of commerce, is the outer bark of the cork oak. When it has attained a diameter of approximately five inches, or, to be more exact, measures forty centimeters in circumference according to the Spanish governmental regulations, which the tree does usually by the time it is twenty years old, the virgin cork, as the first stripping of bark is called, is removed. ”

“ The corky part of the bark which is outside is composed of closed cells, exclusively, so built together that no connection of a tubular nature runs up and down the tree, although horizontal passages radiating toward the woody parts of the tree are [26] numerous. In the woody part of the tree, on the contrary, and in the inner bark, vertical passages or tubes exist, while a connection is kept up with the pith of the tree by means of medullary rays. In one species of tree, known as the cork-oak, this is strongly developed. ”

“ The inner cannot be removed without destroying the life of the tree.
Virgin cork is not of much value; it is employed only for nets, and has no elasticity.
Only after the third harvest is the cork in perfect condition. The tree is then about forty years old. It is first skinned (démasclée) when the tree is aged twenty or five-and-twenty. The second peeling takes place when it is aged thirty or five-and-thirty. The third and best is collected when the tree is between forty and forty-five years old. ”

“ If the soil is poor, the cork is thin but of fine quality and very appropriate to make the best stoppers. If, on the contrary, it is rich, the cork is thick but spongy. Consequently it is requisite to treat the cork tree in such a manner that whilst the cork grows thick it will at the same time be fine in texture. ”

“ Cork trees flourish in Hampton Court Park, where there are two large ones. There are also some ilexes, or evergreen oaks, in Bushy Park, of a very large size, and apparently as hardy as [pg 268] any other tree there. The avenues in that park are perhaps the finest in Europe. There are nine of them altogether, the centre one, formed by two rows of horse-chestnut trees, being the widest. The side avenues, of which there are four on each side of the main avenue, are of lime trees, and the whole length, including the circuit round the Diana water, is one mile and forty yards. ”

“ A cork tree does not produce fine-grained cork till it is fifty years old. Cork-cutting, which formed an important industry in the mountain villages, is gradually leaving them and settling in the towns on the railways, on account of the greater facility of transport. ”

“ The rock elm or cork elm chooses dry, gravelly upland and low heavy clay soil, on rocky slopes and river cliffs, from Ontario and New Hampshire westward through northern New York, southern Michigan to Nebraska and Missouri. It is more abundant and of largest size in Ontario and in the southern peninsula of Michigan.
Its leaf is small, thick, and firm, dark green, and turns to brilliant yellow in the autumn. Its flowers and fruits are borne in racemes. At any season, one knows this cork elm by the shaggy bark on its stout limbs that make the tree resemble a bur oak. ”

“ The greatest care is used to avoid injuring the inner bark. These slabs of bark are heated and slightly scorched; this causes them to flatten, closes up the pores, and gives toughness to the whole material. What should we do without cork for jackets, cork legs and arms, cork apparatus in lifeboats, and other appliances for saving people from drowning? Our cork tree with its marvellous bark is by no means the least valuable specimen in our wonder grove. ”

“ The children declared that the cork-oak was the best tree of all, but they agreed with their governess that the entire oak family was made up of grand and useful trees.
"Our American oaks," said Miss Harson, "are very handsome in autumn because of their brilliant foliage; the scarlet oak, which turns to a deep crimson and keeps its leaves longer than any of the other forest trees, is the most showy of the species. But we have no cork oaks, and no oaks that we know to be a thousand years old. ”

“ The poor of Spain lay planks of cork by their bedside to tread on instead of carpets. Sometimes they line the inside of their houses, built with stone, with this bark, which renders them very warm and corrects the moisture of the air. Loudon relates that in the celebrated convent at Cintra, Portugal, several articles of furniture are made of this tree. Virgin cork, or the first bark of the tree, is now very much used for window flower boxes, grottoes, etc., while the subsequent grades are used for small architectural and geognostic models. ”

“ The stem branches generally low down, occasionally at a height of 8-10 feet, and the branches are vertical, so that the tree has no width of crown. Owing to the scarcity of the smaller branches the vertical ones are crowded with leaves, and from February to April with flowers, for several feet, there being no side twigs, these being replaced by small shoots covered with bracts.
The Bark is silvery grey with a soft sheen, smooth and very thick, large scales peeling off in season. The effect of fire on young stems is to produce great bosses of light brown cork, often charred. ”

“ But such a thing is rarely allowed to happen: the suber is of too much value to man. After it is taken from the tree and has undergone due preparation, it appears in our shops and houses under the name of cork"
"I should like to see how they get it," said Malcolm.
"The trunk is regularly marked around in deep cuts, which begin close to the branches and go down almost to the roots. A ladder is used to mount to the upper part of the trunk, and the cuts, or incisions, are made with a long knife or with an axe. Then they strip off the sheets of cork between the circles. ”

“ The thickness of the bark ranges from 1.27 centimeters to 6.85 centimeters, while the yield also varies greatly [18] from twenty to 75 kilograms [18] per tree, depending upon its size and age. After the first stripping the tree is left in the juvenescent state to regenerate, and great care must be taken in the stripping not to injure the inner skin or epidermis at any stage of the process, for the life of the tree depends upon its proper preservation, for if injured at any point, growth there ceases and the spot remains forever afterward scarred and uncovered. ”

“ After eight or ten years this is also removed, and, while more valuable than the virgin cork, it is not as fine in quality as that of the third and subsequent strippings, which follow at regular intervals of about nine years. At the age of about forty years the oak begins to yield its [Pg 14] best bark, continuing productive as a rule for almost a century, although cork trees several hundred years old are not unknown. ”

“ The bark will bear cutting every ten years, commencing when the trees are about that age; but it should not be cut till the inner bark is an inch or an inch and a quarter thick. I consider that the bark of old trees is less valuable. Some of those we saw in the forests of the Gallura and Barbagia must have been the growth of many centuries. It is calculated that each tree, on an average, produces upwards of 30 lbs. of bark at a cutting; there are about 220 lbs. in a quintal, worth, at Marseilles, 20 francs; and a quintal of cork makes from 4500 to 5000 bottle-corks. ”

“ The stems of the cork elm and the mossy cup oak have these peculiar corky layers, but neither of them have smooth, polished stems between the broken ridges, nor such radiant color as those of the liquidamber. When this tree [Pg 145] grows in open situations its trunk divides a short distance from the ground, and the branches form a pyramidal head. In moist Southern forests, however, where the liquidamber grows to be very tall, its trunk is straight, a uniform size in diameter, and often undivided into branches to the height of seventy or eighty feet. ”

“ Sometimes the corky layer grows and forms new layers, inside of the old, for years, as in the Cork-Oak, the Sweet Gum-tree, and the White and the Paper Birch. But it all dies after a while; and the continual enlargement of the wood within finally stretches it more than it can bear, and sooner or later cracks and rends it, while the weather acts powerfully upon its surface; so the older bark perishes and falls away piecemeal year by year. ”

“ It is used also by fishermen as floats for their nets.
These various applications were known to the Greeks and Romans, as shown by the works of Theophrastus and Pliny. The latter says of the cork-oak: “Nothing is utilized but its bark, which is very thick, and which is renewed in measure as it is removed. This bark is often used for the buoys of anchors and ships and of fishermen’s nets, for the bungs of casks, and for women’s winter foot gear. The Greeks called the cork-oak the ‘bark tree’.... Cork bark is used as a covering for roofs.” ”

“ The rock elm might be mistaken for a bur oak were the leaves not decided proof that it is an elm. The limbs are shaggy, and the twigs winged by the corky bark. Indeed, another name for the tree is the cork elm. The framework of this tree is stiff and irregular, a decided contrast to the graceful drooping top of the American elm, whose symmetry is one of its best points.
The wood has its fibres so interlaced that no wood excels it in toughness and springiness. It is the wheelwright’s choice. It makes the [154] finest bridge timbers, and the best axe handles, and wheel hubs. ”

“ It is a fine street and park tree. The Cork Elm is a tree seventy to ninety feet high, growing from Quebec and Vermont westward to Nebraska and Tennessee. The wood is considered the best of American elms, and is much used for agricultural implements and bridge timbers. The Slippery, or Red Elm is a tree sixty to seventy feet high, growing from Ontario to Florida, westward to Nebraska and Texas. The wood is durable in contact with the soil and is much used for fence posts and railway ties. The mucilaginous inner bark is used in medicine. ”

“ With other Terminalia species it often forms over 50 per cent. of the forest and occurs pure in small groups. Usually a small tree, 15-20 feet high, it attains over 30 feet, with a short bole and widely spreading branches forming a large and very open crown. The distinguishing feature is the cottony felt covering of both sides of the leaf, the unequal basal lobes, and the downy fruit.
The Bark is grey or blue-grey, with very deep fissures and prominent vertical, wavy ridges of hard cork, typical of the genus. The slash is yellow, rapidly darkening on exposure. ”

“ It remained for the elder Pliny, however, in his wonderful work on natural history, written in the first century of the Christian era, to make the most remarkable reference to cork to be found in ancient literature: “The cork oak is but a very small tree and its acorns of the very [Pg 7] worst quality * * *; the bark is its only useful product, being remarkably thick, and if removed will grow again * * *. ”

“ An open park-like country, beautiful with trees and turf, is defaced only by charred spots where the cork-woods have been burned by the natives to effect clearings much less in extent than the space thus denuded. Ten acres of cork trees will be thoughtlessly burned to make one of fig-orchard. ”

“ Nor is this kind of Texture peculiar to Cork onely; for upon examination with my Microscope, I have found that the pith of an Elder, or almost any other Tree, the inner pulp or pith of the Cany hollow stalks of several other Vegetables: as of Fennel, Carrets, Daucus, Bur-docks, Teasels, Fearn, some kinds of Reeds, &c. have much such a kind of Schematisme, as I have lately shewn that of Cork, save onely that here the pores are rang’d the long-ways, or the same ways with the length of the Cane, whereas in Cork they are transverse. ”

“ This résumé of the cork-producing countries of Europe will convey some idea of the extent of the forests, and will also show the climate sort by the tree; for it is proven that it flourishes best in an altitude of 1600 to 3000 feet, in an average mean temperature of 55° Fahrenheit ”

“ Up to their twentieth or twenty-fifth year the ground is cultivated as if it were a vineyard, rooting up at that age the vines on account of producing less fruit, and also on account of the cork trees being pretty well grown up and no longer requiring the shelter of the vines. ”

“ The forests suffer great damage from fires, occasioned in part by the custom of burning up the grass every autumn, and in part by incendiarism. In 1902 alone, according to the British consular report, ``at a moderate estimate the number of trees damaged or destroyed might be put down at 6,000,000.'' Forestry is a state-protected industry, the government owning over 500,000 acres of forest. The chief tree which has commercial value is the cork, and the stripping of the bark is under official supervision. The first cork harvest was gathered in 1890, when 1474 cwt. ”