The cork oak
The species appeared more than 60 million years ago in the Western Mediterranean. Man
learned thousands of years ago how to extract the bark without harming the tree and how
to use this unique material.
The bark of the cork oak is composed of micro cells, which are generally of polyhedral form.
The inter-cellular spaces are filled with air. This honeycomb structure and the cellular
membranes enable the special characteristics of cork and its multiple applications.
Lightweight, resistant to wear, impermeable, elastic but of stable size, cork has a perfect
capacity for heat insulation and vibration dampening. It has been used in the manufacture
of many products for thousands of years. It is highly ecological.
The barking of a cork oak can only be carried out every 9 years. The barking season lasts
from July through to September.
Segments of bark, as large as possible, are detached with great care, ensuring that the
phellogen base is not affected. This layer not only produces the usable material. It also
ensures the regrowth of bark of the tree.
The first harvesting of a cork tree can only be carried out when the tree is at least 25 years
old and the perimeter of the trunk reaches 70 cm. The cork obtained from the first stripping
is called “male cork”. It is used for low-quality products such as floor tiles, pin-boards, and
At the time of the second removal (secundeira), cork is still not yet ready to be made into
bottle stoppers. Ripe and perfect “female cork” for wine bottles will not be harvested for
another 9 years. So the cork oak must mature for at least 43 years before it can produce
cork for wine stoppers.
A bit of history.
The galleons of 16th century, venturing into unexplored seas, were known as “the cork
galleons”. Benches, trunks, bowls, mess tins, shoes and other objects were all carved from
The use of cork to seal wine bottles began in the 17th century. The cork stopper then
flourished with its incomparable capacity to preserve the quality of wine, especially
Seacork’s raw material comes from the cuttings of wine stoppers. The cuttings are reduced
to granules and mixed with a special resin. Blocks of cork, which can be cut into sheets of
different thicknesses, are compressed at high pressure.
The World Wildlife Fund has published an article in English explaining the ecological
advantages of cork. http://mediterranean.panda.org/?4802/Put-a-cork-in-it. Reconstituting the
bark of a cork tree consumes 3 to 5 times the CO² released when the cork is consumed.