The Cork Oak (Quercus suber), which is endemic to northwest Africa and southwest Europe, helps to produce the impermeable, buoyant, elastic, and fire retardant cork. This tree is not just unique in its properties, but how it is harvested.
Growing up to 65 tall, unlike other oak trees, the cork oak is an evergreen and does not drop its leaves. Cork oaks are found in approximately 6.6 million acres of Mediterranean forest in Portugal, Spain, Italy, France, Morocco, Algeria, and Tunisia.
Generally when individuals think of harvesting, they think about the removal of that plant for that season. The cork oak though is the only tree you can remove all of the bark without harming the trunk. To learn more about these forests and how the tree thrives in remarkable environments and is able to be sustainably harvested, be sure to watch our TED talk at TEDxSalem:
For thousands of years cork has been harvested by hand, with an axe that has changed little. Like sheering sheep, the bark can be stripped for its cork once every 9 years. One tree, which lives up to 200 or 300 years, can be harvested over 16 times. This means that generations of families are harvesting the same tree in the same location over decades. These agriculturists are highly skilled in how to chop off the bark without damaging the cambium layer of the trunk of the tree. In fact, they train for roughly 8 years and are the highest paid agricultural workers in all of Europe.
These trained professionals are able to slit the outer bark and peel it from the trunk with a specialized cork axe after all major branches are carefully stripped by hand. This bark is actually extremely light and can easily be carried off after being stripped.
The harvested cork is then removed from the forest and placed to air for 6 weeks to improve quality, as the photo above shows. Corks are then popped through these slabs and the entirety of the rest of the bark goes to use.
This remaining cork is ground up and processed for use in creating cork and rubber compounds. This “blocker waste” is used to make decorations, bulletin boards, construction materials, and more. The biomass of cork is also used to help power their plants, making it the most sustainable and environmentally practice of forestry on the planet.
In addition to being environmentally friendly, these cork forests are also a vital source of income for thousands of family farmers. Since these trees can be harvested multiple times over decades, these families have worked in these forests for generations. Our Bark to Bottle eco-tour is one of the best ways to explore these unique trees and get a first hand experience in the heart of the Spanish cork forests.