The study of its origin leads us to that romantic part of the world bordering the Mediterranean Sea from which we have already received so much in all branches. The cork-producing country practically covering the whole of Portugal sweeping toward the East through the southern districts known as Andalusia and Estremadura, thence northeast, embracing thousands of acres of forests in Catalonia. Spain and Portugal dividing honors among the nations in the annual yield of raw material, with perhaps the advantage leaning slightly to the latter.[4] This being partly due to increased area, no doubt, as the geographical situation is the same but with the irrigation feature slightly in favor of Spain, as through the corkwood country flows the Guadalquivir River in addition to the three which also pass through Portugal, consisting of the Douro, Tagus and Guadiana in the west, and the Ebro in the Gerona district.
Tunis and Algeria[5] rank next in importance with Southern France, including Corsica following closely. Italy (Tuscany) too with the help of Sardinia and Sicily continuing to be quite a factor in meeting the demand for the crude material, while across the Strait of Gibraltar the sun-scorched forests of Morocco at El-araish are as yet undeveloped, although rapidly being pressed into service.
The geographical formation of Portugal is extremely favorable for the rearing of cork trees, every evidence of this characteristic being well marked by the densely thick groups of cork trees to be seen in certain regions, especially in the Valley of the Tagus and the Sierra de Portalegre provinces of Alemtejo and Algarve, which are the chief bearing centers of this country,[6] the area devoted to their cultivation being approximately 366,000 hectares.
In Spain it is found in the Provinces of Gerona, Caceres, Andalusia, Huelvas, Seville, Cadiz, Ciudad Real, Malaga, Cordoba and Toledo in the order named.
According to a calculation made by the administration of forests the extent of cork forests in Spain is about 255,000 hectares,[7] viz. 80,000 in the Province of Gerona, 54,000 in Huelvas, 32,500 in Caceres, 28,000 in Seville, 20,000 in Cadiz, 11,500 in Ciudad Real and 9500 in Cordoba. The remainder is distributed between ten other provinces. [8]
In the Province of Gerona is included a large territory stretching northward towards the Pyrenees to the Valley of the Muge and Ter. In France, according to Consul Goldschmidt of Nantes, the cork-producing territory is divided as follows: Var, 280 acres; Lot-et-Garonne, 27 acres; Landes, 32 acres; Corsica, 40 acres; making about 379 acres in all.
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; and at points beyond 45° north latitude its successful propagation is doubtful.The Mediterranean Basin is particularly suitable for the rearing of corkwood, and although many attempts have been made to transplant the seed, the results have proven fatal.
Notable among these attempts being the American ambition to introduce the tree in the United States. Portuguese acorns were brought to Wayne County, Mississippi, and planted in 1859; the result, as far as the growth was concerned, was splendid; but after a wait of eleven years, the final crop was not a commercial success. Another attempt was made in 1872, in southern California, but with no better outcome than the first, in which some of the trees attained to a height of thirteen feet (3.965 meters) and the stem, to a diameter of eleven inches (2.794 decimeters), including the cork, which attained a thickness of one inch (2.540 centimeters). This evidently rapid growth would infer that the 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.[9] And Consul S. C. Reat, writing from Tamsui, recently reports the efforts of the Japanese Government to plant cork trees in Formosa and the Ogasawara Isles, in the endeavor to supply small corks to the Japanese merchants, the result of which, is yet to be learned.
The Tree and Growth
Many botanists consider the cork oak of Europe as belonging to two species, one chiefly characterized by annual fructification and the persistence of the leaves for two or three years (Quercus Suber, LinnÆus); the other by biennial fructification and annual persistence of the leaves (Quercus Occidentalis, Gay). [10]
In the French departments of the Landes and Gironde the Quercus Occidentalis forms extensive woods, as also in Spain, Algeria and in some parts of Italy, while the Quercus Suber is a native of the Atlantic side of France and Portugal, where this tree grows to the greatest perfection, and to which countries we are indebted for the major part of our supply. The cork tree bears a general resemblance to the broad-leaved kind of (Quercus Ilex, Holm) or evergreen oak, of which species some authors consider it only a variety; but when full grown it forms a much handsomer tree.
“In the localities to the north the cork is better than those exposed to the south. It grows and develops in ground of very little depth, and sometimes in ground, in appearance very stony. It is seldom found in calcareous soil, preferring always a soil of feldspar, and like the chestnut flourishes best in a sandy one.” [11]
The cork-oak attains a height of from six to eighteen meters, at times reaching fifty meters[12] and measures as much as 1.22 meters in diameter.[13] Its branches are covered with small evergreen leaves, which are rather spongy and velvety to the touch, have a glossy appearance and a saw-tooth edge, measuring about three to five centimeters[14] long and one and one-half to two wide. The roots are strong and spread considerably, and frequently are to be seen on the surface of the ground. The flowers or blossoms make their appearance in May; the fruit ripens in the fall or winter, from September to January, and falling from the tree as soon as ripe. Three qualities of acorns are to be observed according to their time of ripening and are called, “brevas primerizas de San Miguel,” which ripen in September; the second or middling “Martinencas,” which ripen in October and November; and finally the “tardias Ó palo-Meras,” which ripen in December and January. These acorns form one of the forest’s chief sources of revenue, since fed to swine, they give a peculiarly piquant flavor to the meat, Spanish mountain hams being noted for their excellence. [15]
In the following paragraphs I will quote principally from Consul Schenck’s Report, 1890, relating to the growing and procuring of the bark for shipment, with interpolated sentences and slight changes, made necessary by other data at hand. The most common practice is to cultivate this plant by sowing, which is frequently done, above all, in ground somewhat manured, making alternate furrows with vines. 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. At the end of even one year it is difficult to transplant the cork tree on account of the length of the roots, principally the central one, and if the trees are put out with the intention of transplanting they are generally sewn in a false ground bottom made artificially at a certain depth with layers of stones or bricks. French silviculturists recommend about 110 to 120 trees to the hectare (2.471 acres).
The cork tree gives but little shade, which contributes greatly in causing the soil to become dry. To avoid all these inconveniences, which are highly unfavorable to the good production of cork, it is requisite that young plants grow up with sufficient foliage, so that the branches touch each other, and even overreach, till they are about twenty-five years old. It may be convenient, if there is not sufficient foliage from the cork trees themselves, to introduce secondary species, such as the elm tree, ash and pine, known as (pi meli), these being depended upon to supply the requisite coolness and manure to the ground. 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. This is of course an agricultural problem and may differ from year to year in the necessary details.
