Recently harvested cork trees growing in a cork forest in Portugal.
We know the cork oak tree is amazing for many reasons, the most popular probably being its ability to grow back its bark after each harvest. What may not be known is the crucial role the cork oaks play in both CO2 sequestration and oxygen production. Cork trees, like all trees, absorb carbon dioxide through photosynthesis, storing carbon in their roots and branches while releasing oxygen back into the environment. So, what makes this tree different from other trees?
The answer is in the bark!
The bark of the cork oak tree is harvested, but the tree itself is not cut down. It continues to grow and, therefore, continues to store carbon. In contrast, most other trees harvested for other purposes, such as lumber, require the tree to be cut down, which ceases carbon sequestration. The cork oak, which can grow for over 200 years, steadily increases its carbon storage capacity. Most of this carbon remains locked away in the tree as it continues to grow. When the cork bark is harvested, the tree actually absorbs more carbon dioxide as it requires the energy produced during photosynthesis to regenerate its bark.
How does this work?
Through photosynthesis. The simple explanation is that trees absorb carbon dioxide from the air and combine it with water to create sugars and oxygen. The oxygen is released into the environment while the sugars, which are composed of carbon, travel throughout the tree, providing it with energy. The carbon is sequestered within the tree, stored in its roots, branches and trunk.
Are cork products carbon neutral or even carbon negative?
They sure are. This means the amount of carbon that is stored is more than what is released and used in the production of products.
Although this explanation simplifies the carbon capture process, it shows that cork products and cork trees are extremely beneficial to the environment and have a climate-positive impact!
Looking up towards the canopy of this cork oak tree with its natural cork bark.