|Cork is the outer bark of the cork oak tree, Quercus Suber, which grows
mainly in the Mediterranean region. The bark is a vegetal tissue
composed of an agglomeration of cells filled with a gaseous mixture
similar to air and lined with alternating layers of cellulose and
suberin. Cork's elasticity, combined with its near-impermeability,
makes it the perfect material for making bottle stoppers, floor tiles,
insulation sheets, bulletin boards and other similar products. Because
of its remarkable qualities, cork is used in high-tech applications
including car engines, dam mechanisms and airport runways. The
aeronautics has used cork as a thermal insulator in space shuttles.
The use of cork as a raw material dates back to Phoenician and Greek
times. Cork began to become known all over the world as an effective
bottle stopper for wine. In fact, cork is the only material that makes
a perfect seal during the ageing of the wine.
Today, cork is a valuable resource for Portugal, representing one of its most important export products.
The cork oak
|Cork oak forests cover approximately 2.5 million hectares across the
Mediterranean region and most of them are located in seven countries:
Portugal, Algeria, Spain, Morocco, France, Italy and Tunisia.
The tree has a life span of 250-350 years. Each cork tree must be 20 to
25 years old before it can provide its first harvest of cork bark. This
cork is known as virgin and has a hard and irregular structure. After
the virgin cork has been stripped, a new layer of cork begins to grow.
The first of these layers, harvested after nine years, is called
secondary cork; cork harvested after this second stripping is known by
the Portuguese word: amadia.
A typical tree produces several hundred kilograms of cork at each
harvesting and will survive for many generations. The bark is stripped
off the tree in sections by highly skilled men using special axes, a
traditional manual skill that dates back many hundreds of years.
Cork is harvested on a sustainable basis and the
stripping of the bark does not harm the tree in any way. The bark grows
back completely, taking on a smoother texture after each harvest. A
cork oak tree can be safely harvested up to 20 times during its life
cycle, making cork a truly inexhaustible natural resource.
New plantations of cork oak trees are planted each year to ensure the
level of cork production is maintained. Cork oak trees cannot be felled
or removed without government authorization, which is rarely granted.
Portugal, which produces more than 50% of the world’s cork, has been
particularly careful to safeguard this valuable resource. The first
Portuguese laws protecting cork oak trees date back to the 14th
century. At the beginning of the 20th century, it became illegal to cut
down cork oak trees, except for essential thinning or the removal of
old, non-productive trees.
In a context of increasing concern for the environment, cork remains
the only tree whose bark can regenerate itself after each harvest -
leaving the tree unharmed. It is truly a renewable, environment