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How Artisans Harvest Wine Corks In Portugal

Cork trees can be harvested only every nine years. Credit: Courtesy of APCOR

Cork trees can only be harvested every nine years. Credit: Courtesy of APCOR

The ax strikes the tree with a dry, hollow crack. The man wielding it carefully uses the edge of the blade to pry a thick piece of cork from the tree, then hands it down the ladder to a worker waiting below. In the surrounding forest, the crew continues separating the bark from the trees in the summer heat, until the day’s harvest is collected. There are no machines to do this work. It requires skill as well as physical strength, and the stamina to withstand 90-plus-degree temperatures, swarming flies and dry, thorny brush that tears at workers’ pant legs.

This was the scene I witnessed in late July, during the annual cork harvest in Coruche, Portugal’s cork capital. The harvest takes place each year between May and August, as it has for centuries.

Cork is the name for the bark of the cork oak tree (scientific name Quercus Suber L.), an ancient species dating back millions of years. Cork oaks grow primarily in Portugal, but also in France, Spain, Italy and Morocco. Because these unique trees have the ability to regenerate their outer layer of bark after it’s been stripped, there’s no need to cut down the trees in order to harvest the cork.

Portugal is the world’s largest producer of cork, and the country is home to nearly 2 million acres of cork forest, or montado. Cork trees can live 500 years or more if their bark has never been harvested, and up to 150 years if it has.

In the wine world, people often marvel at the patience of grape growers, who have to wait three years for a new vineyard to produce a usable crop. That’s nothing compared with the long-range planning required of Portugal’s cork farmers. Once a cork tree is planted, it takes 25 years before its bark can be harvested.

The first year’s bark isn’t good enough for wine stoppers, so it’s sold at a much cheaper rate for flooring and other byproducts. It takes nine years for the bark to regenerate before it can be harvested again, and even then, it still isn’t viable for wine corks. Only after nine more years, at the third harvest, does the tree produce bark that’s suitable for stoppers. In case you’ve lost count, that’s 43 years of waiting!

Skill and strength

Watching the harvest crew in action last month, I came to understand why these are the world’s highest-paid agricultural workers. Stripping the bark is hot, difficult work, and requires both care and muscle. The harvesting is done mainly by men, known as descortiçadores (debarkers),who earn up to 90 euros ($120) per day wielding sharp iron axes called machadas.

As my guide, Sofia Ramos of the Coruche Forestry Association, pointed out, this work cannot be done by just anyone; it takes specialized skill to remove the bark without damaging the trees. The technique is passed down through generations, and is not something that can easily be picked up by migrant workers from non-cork-producing regions. “They have ancient knowledge,” she told me, “and that is very valuable.”

As I stood in relative comfort, but still dripping with sweat and swatting flies, I watched the workers strip the gnarly gray-brown bark from the trees, leaving behind smooth trunks the color of mahogany. Moving swiftly and efficiently, it took each two-man team about 10 minutes to strip a tree before moving on to the next one.

Although the harvest process appeared to be fairly simple from my vantage point, I learned that it actually consists of many distinct steps:

First, a vertical cut is made in the bark, while at the same time, the edge of the ax is twisted to separate the outer from the inner bark. Second, the cork is separated from the tree by inserting the edge of the ax between the cork strip and the inner bark, and twisting the ax between the trunk and the cork strip. Next, a horizontal cut is made to define the size of the cork plank to be extracted. Finally, the plank is carefully removed from the tree so that it doesn’t split (the larger the planks, the greater their value.)


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Portugal's "debarkers" are the highest-paid agricultural workers in the world. Credit: Courtesy of APCOR

Once the tree has been stripped, it’s marked with a number, using the last digit of the year in which the extraction took place. This lets the forest manager know when the trees will be ready for the next harvest.

Each day’s cork planks are stacked onto tractor beds and transferred to a drying area where they rest for three weeks before being transported to a cork processing facility. There, the planks are boiled to remove impurities, trimmed, sorted, cut into strips and finally, punched into stoppers.

The next time I pull one of those stoppers from a wine bottle I’ll be thinking about Portugal’s miraculously regenerating cork trees, and the hardworking descortiçadores who harvest their bark.

Main photo: Cork trees can be harvested only every nine years. Credit: Courtesy of APCOR

Zester Daily contributor Tina Caputo is a wine, food and lifestyle writer based in Northern California. Her stories have also appeared in the San Francisco Chronicle, Wine Review Online, and Sonoma magazine. 

  • Patrick spencer 8·28·14

    Dear Tina,
    Thank you for the wonderful article on cork and the harvesting process! The more information people have about these remarkable trees and the cork forests importance to the health of our planet, the better.

    Our, nonprofit, forest conservation organization is launching an eco-tour of the cork forests in 2015. The web site: will be “live” late September. We hope you’ll let you readers know about it then. We appreciate your spreading the word, the more we use cork, the healthier the forests. .

    Patrick Spencer
    Executive Director
    Cork Forest Conservation Alliance

  • Tina 8·28·14

    True, Patrick: Without wine corks the cork forests would likely be sold off for development, as the farmers wouldn’t be able to make a living only selling cork by-products for flooring, etc. The wine stopper industry is very important to the Portuguese economy, and keeps workers from going off to work in other countries during hard economic times. I didn’t see any critters in the forest (other than flies) when I was there, but I understand there are animals, birds, etc. living there that also depend on the forest.

  • Alexandre 9·3·14

    I believe the median lifespan for a cork tree is 200 years. Naturally, some can live for longer, but I wasn’t aware that this could be reduced by harvesting the cork. Could you please give me a reference of the study/ies? Thank you!

  • Tina 9·3·14

    Hi Alexandre,

    This information came from APCOR, the Portuguese cork association:

  • Patrick spencer 9·3·14

    Thank you for the reply. It is true that most of the cork for the wine industry does come from Portugal, but there are 6 other countries, (Spain, France, Italy, Morocco, Algeria and Tunisia) where there are over 5 million acres of cork forests. These seven cork producing countries are the home to over 13,000 species of animals. insects and plants that live nowhere else on earth. They employ over 100,000 people and are the cultural lifeblood for these people. The cork forests also keep these 7 million acres from becoming a desert. They absorb over 20 million tons of CO2 each year and provide a significant amount of the worlds oxygen. For more information about these remarkable forests, please visit our website:

    We unaware of any study that shows cork trees will live to be 500 years old, if un-harvested or otherwise. The research we have shows that the average life span is 200-250 years, with some living up to 300 years. The harvesting has no detrimental affect on the trees. In fact, trees that are harvest every 9 years, will absorb an additional 10 million tons of CO2, in its life, over a tree that is unharvested.

  • António Sousa 9·5·14

    Dear Patrick,
    the fact is that when you harvest a cork tree it looses strenght. After a cork harvest there are always some trees that die. This is cruel but true. The tree dies due to the climate changes. The summer’s, nowadays, are hotter and the period without rain alied with high temperatures dries some trees ( they already are debilitated due to the harvest ). It is in the process of regeneration of the cork bark that the tree absorbs all that CO2!

    Another matter of great interest and concern are the causes of death and decline of the montados ( the cork trees forests ). There are, overall, 17 insects and fungus that afect a cork tree and can lead to it’s death! These are the enemies of a cork producer!!

    Best regards,

    António Sousa

  • Patrick Spencer 9·5·14

    Dear Antonio,
    I think it is important for those reading these posts to have a greater sense of clarity regarding the statements you have posted, as it might seem as though cork harvesting is a “negative” form of forestry. Though a small percentage trees do die after harvest, there are many factors that have a direct affect on those trees, including age and general health of the tree. Insects and bacterial disease are a factor for cork oaks, regardless of harvesting or not. Quite often a tree that is visually inspected and deemed to be in poor health, with not be harvested, as the bark of that tree will be of little use.

    Yes it is true that climate change is affecting the Montado, but climate change is affecting the entire planet, this is not an isolated issue. It is important to recognize that the cork farmers themselves play a significant role in the health of the Montados. Planting Pine and Eucalyptus to replace Cork Oak is leading to soil degradation, increased ground water consumption and elevating the risk of forest fires. Having said that, the Montados of Portugal are, by all accounts, in a healthier condition now, than they were 25 years ago, even with climate change. Continued forestry research, advanced farming and harvesting practices and certification by the FSC have helped enhance the sustainability of these forests.

    In closing I feel it is important to reiterate, every major forestry and conservation organization on our planet has determined that harvesting cork, is the most sustainable and environmental forestry in the world.

  • sylvia Zur 2·23·15

    Dear Tina, We are 2 couples who will be touring Portugal in May. I would like to know if there are guided tours to show the cork harvesting .

  • Tina Caputo 2·23·15

    Yes, Sylvia, there’s the Cork Route that is located near Algarve. On The Cork Route you can walk through the cork groves, hear the stories, find out about the techniques for preparing and processing cork, etc.

    I hope you have a wonderful trip!