The cork oak, Quercus suber, is a tree from the Mediterranean area, from the Tertiary Era, between the Eocene and the Miocene epoch (20 – 60 MA). Present since the formation of the Mediterranean basin. It is endemic to Southwest Europe and North Africa.
The tree crown can have several rounded shapes, with a maximum height of 20m. The taproot facilitates a deep perforation of the soil after germination, which contributes to the fixation of the tree and the capture of water in the ground’s lower levels. The root also develops robust lateral roots that branch and form an extensive three-dimensional network of root hairs.
The major difference from other oaks is the suberose tissue, the cork, which surrounds the trunk and branches. The cork oak is the only plant species that produces this tissue capable of regenerating itself after each extraction, with high economic importance. Cork extraction takes place every 9 years because it is the average period for the cork to reach an adequate thickness for the production of stoppers. This raw material has unique chemical, physical and mechanical properties, which is why it is used in various sectors of the industry.
The cork oak is a very resistant species, with physiological adaptations to dry environments, which presents a slow growth. Its ability to survive in environments with low water availability is probably related to its deep and extensive root system, capable of obtaining water from the deepest areas of the soil. Given the environmental conditions, and soils poor in nutrients, in which it grows, we can conclude that the cork oak is a very undemanding tree.