Wood is one of those building materials that have been known to mankind since ancient times. The volume of its consumption is growing every year, but because many species were on the verge of extinction.
The cork tree, which has been used by man for thousands of years, also belongs to the latter.
It belongs to the genus of oaks. The difference from relatives is that by about five years its branches and trunk are covered with thick bark with unique properties. But you can only shoot it by the age of 20. Note that you can do this up to the age (of a tree, of course) 200 years!
After the first collection, at least 8-9 years are required during which the restoration of the cortex takes place. A tree between the ages of 170-200 yields approximately 200 kg of high quality raw materials.
The peculiarity of this oak is also that it belongs to the evergreen species. The leaves resemble those of Russian oaks, but from below are covered with a significant layer of fluff. The cork tree itself is quite large: the height can reach 20 meters, and the diameter of the trunk - meters.
The Latin name is Quercus suber. It grows at an altitude of not higher than 500 meters above sea level. Most oaks of this type are found in Portugal, which is why the country's budget receives considerable cash infusions, originating from the export of cork, which annually increases its value.
From ancient times, man knew that cork tree gives this most valuable raw material, and therefore it has long been cultivated. Note that there is a false representative of this genus, Q. crenata, which is quite widespread in southern Europe. Its cork layer is so small that the tree is bred exclusively for decorative purposes.
In Portugal alone, over 2 million ha are occupied by Quercus suber oak plantations! In addition, approximately the same number of territories is used for this throughout Southern Europe.
During the year, all plantations produce more than 350 thousand tons of bark, but this amount has long been insufficient to meet demand. That is why the wild cork tree was almost completely destroyed.
By the way, what is the uniqueness of cork as a material? The fact is that it is a natural polymer whose structure resembles a honeycomb in a bee hive.
Each cubic centimeter of this material can contain up to 40 million such cells, which are delimited with each other using partitions from the cellulose component.
Simply put, each capsule is filled with air, so even a small piece of cork is very elastic. This property gives the material complete water resistance and the ability to restore its original state even after strong pressure.
That is why the cork tree (whose photo is in the article) received such wide appreciation from furniture makers.
In addition, suberin is a part of the bark (it is a mixture of fatty acids, waxes and alcohols). It is unique in that it gives the wood refractory and antiseptic qualities. Cases are known when, during forest fires, cork oaks remained completely intact, except for scorched bark and dried leaves from the heat.
Thus, the cork tree bark is a unique material bestowed upon man by nature.
