More about the Cork Oak Tree

The cork oak or quercus suber is a medium sized evergreen tree that grows up to 20m. It is native to Southwest Europe and Northwest Africa. The cork oak’s leaves are 4 to 7 cm long and weakly lobed, dark green on the top and paler on the underside. The acorns are 2 to 3 cm long in a deep cup with fringed, elongated scales.

The cork oak provides a natural habitat for a variety of animals including the Barbary ape in Africa and the Iberian lynx in Spain and Portugal. The Iberian lynx is the most endangered species of feline. For this reason it is vital that the cork oak forests of Spain and Portugal be preserved and the harvesting of cork oak be carried out with the minimum of disturbance to the natural habitat.

Where the cork oak grows it is hot and dry and the frequent witness to forest fires. Whereas the other trees of the forest have to regenerate from seed or the base of the burnt out tree, the cork oak survives the flames. It manages this because the bark of the cork oak is thick and insulates the tree from harm. Thus, after a fire it is the cork oak that is the first to restore the canopy to the forest. Using cork as a flooring material similarly insulates a room against heat loss, sound and fire.

Cork oak forests cover 25,000 square kilometers of land in Spain, Portugal, Morocco, Algeria, France and Italy. 50% of the world’s harvested cork comes from Portugal. Cork is so important to Portugal that it is illegal to cut down cork oak trees and special permission is needed to fell old and unproductive trees.

The cork oak grows a thick bark that is called cork cambium. The first cork cambium harvested from a young tree is called ‘virgin cork’. Virgin cork is irregular and not used for cork flooring. The cork cambium regenerates in 9 to 12 years. In the lifetime of a cork oak it can be harvested 12 times.

Cork harvesting is done without machinery. It requires a team of 5 laborers with a small axe to peel the bark off the cork oak tree. The cork industry produces 300,000 tonnes of cork and is estimated to be worth €1.5 billion and employs 30,000 people. Traditionally, over half of the cork harvested went to make wine bottle stoppers. However, many wine manufacturers have changed to using plastic stoppers. This change is partly because of the recent interest in cork as a renewable resource. Much of the cork used for cork flooring is recycled from unwanted wine bottle stoppers. So many cork floors are made from the recycled product of a renewable resource. That makes cork flooring an exceptional type of sustainable flooring.

Finally, a little cork is made in Eastern Asia. It is taken from the Chinese Cork Oak or Quercus variabilis.