The Cork Harvest

As part of Vinocamp Lisboa I joined a group of cool wine lovers and headed to Coruche to spend the day at the cork forest during the harvest.

Portugal accounts for roughly 50% of the world’s cork and despite living practically in the middle of the cork forest (actually 30 min from it), I had never been to a cork harvest before. This time I spent a full morning filming, taking notes and generally discovering one of the most wonderful natural and renewable resources available in the World.

Cork is harvested from cork oak trees using the same methods that were already being used hundreds of years ago. It’s a hand labour-intensive effort that requires task-organized and skilled teams of workers to spend full days working together in one same piece of land.

Men and women are each given different tasks. While men climb the cork oak trees with axes to cut the cork, women collect it on the soil and bring it back to a standing-by tractor. After each tree is finished, a woman comes with a paint bucket and marks the tree with the last digit of the current year. This is a way to control in how many years one tree will be again available to be harvested again. Interestingly there’s a woman whose sole job is to guarantee that everyone’s drinking plenty of fresh water throughout the day.

After the harvest, cork pieces used to be left to dry in the forest from 3 to 6 months. These days cork is transported back to a cleaner centralized location (out of the forest) where the drying process can happen in safer disease-free conditions that will affect the quality of the finished product.

Each cork oak tree can live between 150 and 250 years but it only gets harvested once every 9 to 12 years. When a tree is actually harvested only the bark is extracted and in the following 9 years a new layer of cork will be allowed grow. This is why cork is considered a natural and renewable resource. It’s is also a protected resource as cork oak trees cannot legally be cut down in Portugal (only with special permission from the Ministry of Agriculture).

The following photos are from the harvest process:

Men and women working together in one of the cork oak trees.

Groups of skilled men work carefully with their axes to remove cork but protect the tree.

It is the cork oak tree outside layer that provides the raw material to produce cork.

Cork layers lay on the floor waiting to be picked up by the collecting team.

During each harvest only 50% of the bark is actually removed allowing the tree to protect itself using its natural defenses.

After the natural drying process cork goes into a factory to be processed. At this stage cork pieces are grouped together and inserted into boiling water to make them flatter and more elastic.

Cork after being boiled, flattened and cut into shorter pieces, is selected based on quality and size. Good quality wine corks are directly cut out from the group on the left and then go through further quality control and processing.

Wine corks

Wine corks represent only 15% of cork usage by weight but 66% of revenues (via Wikipedia). Cork is the most used wine bottle closure in the world and despite the many (fairly or unfairly) raised problems it is a respect natural and renewable resource.

What I’ve been seeing, since I joined the wine industry 4 years ago, is the amount of people, work and money being put into research, production and quality assurance to make sure that cork as a material can be used for many years to come as a safe, natural and renewable resource.