CORUCHE, Portugal — The rhythmic noise of axes whacking timber echoes in the depths of the cork oak forest.
However in Coruche, a rural set up south of the Tagus River is called Portugal’s “cork capital,” the bang of timber falling to the ground doesn’t follow the sound of the ax strokes. As a substitute, skilled workers fastidiously peel away the bark from the tree trunks.
This annual rite of extracting cork in the summertime months has been around for thousands of years in the western Mediterranean. Egyptians, Persians, Greeks and Romans former the fabric to smash fishing instruments, sandals and to seal jugs, jars and barrels. As glass bottles obtained recognition in the 18th century, cork grew to alter into the most neatly-appreciated sealant due to it’s durable, water-resistant, light and pliable.
Now cork is experiencing a revival as extra industries ogle for sustainable imaginable decisions to plastic and other provides derived from fossil fuels. The bark is now former for flooring and furniture, to smash shoes and garments and as insulation in properties and electric vehicles. Portugal’s exports reached an all-time high of 670 million euro ($728 million) in the first half of 2023.
However cork is bigger than a fragile inexperienced cloth. Along with to jobs, the forests where it grows provide food and shelter for animals, all whereas sequestering carbon dioxide. And never like most timber grown commercially, cork oaks are never cut down, which formulation their carbon storage capability continues thru the 200 years or extra they reside.
How cork is harvested
With a agency swing, Fernando Tacha strikes the trunk of a cork oak, then twists his ax and uses the take care of to delicately prise the plank.
“I started decreasing cork when I used to be most effective 19. Now I’m 69. However I will fabricate this so long as I will,” he says as he wipes the sweat from his forehead. “It’s a laborious job, however a beautiful one.”
A low, slack-rising evergreen tree, the cork oak is endemic to the Mediterranean. The most intensive forests might maybe maybe even be learned on the Atlantic fly of the Iberian Peninsula. In Portugal, the sphere’s supreme cork producer, the oaks are so cherished they had been chosen as the country’s nationwide tree and are stable by legislation, so it’s forbidden to cut them. Spain is the 2d-supreme producer, adopted by Morocco, Algeria, Tunisia, Italy and France.
The course of of harvesting cork takes precision and years of apply. The stroke of the ax desires to be stable, however furthermore gentle to lead obvious of hitting the internal bark and unfavorable the tree. Because it’s miles so primarily excellent, it’s one in every of top-of-the-line paying agricultural jobs in Portugal.
The bark can most effective be harvested between leisurely Would possibly maybe well and August, when the tree is in its filled with life part of boost, which makes it less complicated to strip the outer layer without unfavorable the tree trunk.
The cork oak is unfamiliar in its ability to regenerate its bark. As soon because it’s removed, workers write the final desire of that 365 days with white paint on the uncovered golden brown trunk — a 3 formulation it used to be harvested in 2023. The bark will slowly develop assist and be ready for yet every other harvest after 9 years.
Paula Salgueira, who has been working in the cork harvest in Coruche for 35 years, extends her hand to contact an oak that used to be appropriate stripped. “It’s chilly,” she says as she caresses the tender denuded trunk. While axmen work in pairs striking off the cork, Salgueira and each other women get the planks in piles for transportation.
The planks will then be stacked exterior in storage areas uncovered to air and daylight hours. After six months of growing old to cast off moisture, they will likely be sorted in accordance with their thickness and quality, then boiled to neat impurities and smash the fabric softer and less complicated to take care of.
From bottle stopper to inexperienced cloth
While most cork is soundless former for bottle stoppers, over the final decade thoroughly different industries were finding recent uses for it.
“We are seeing a rising curiosity in cork as a sustainable cloth,” says Rui Novais, a provides expert on the University of Aveiro in Portugal. “When put next with provides fancy polyurethane foam [used for thermal insulation], products made with cork require much less vitality and fabricate much less CO2 emissions.”
The cork oak’s thick bark adapted to defend the tree from fire, making it a highly effective insulating cloth that’s been former to defend gasoline tanks on NASA spacecraft and electric vehicle batteries. It’s furthermore immune to water and oil, and might maybe maybe face up to compression whereas preserving springiness.
“It’s an unheard of, renewable and biodegradable cloth,” says Novais. “It’s furthermore very durable. It has been demonstrated that cork products remain almost unchanged for bigger than 50 years.”
Share of the carbon absorbed by cork oak timber is transferred to cork products, that will likely be former for long intervals, repurposed and recycled. Several experiences learned that cork is carbon unfavorable, which formulation it can retailer extra carbon than what’s required to fabricate it.
When cork planks are trimmed and punched to fabricate pure cork stoppers, the leftovers are ground into granules and pressed collectively to fabricate cork sheets or blocks. “Even cork grime is former to fabricate vitality,” says João Rui Ferreira, secretary favorite of the Portuguese Cork Association. “It feeds the commercial’s boilers and powers likely the most significant production.”
Recycled cork can furthermore be beaten and composited to smash other products. In Portugal, Inexperienced Cork, a recycling program started by the environmental organization Quercus, has nonetheless and recycled bigger than 100 million cork stoppers since 2009. A the same initiative, ReCORK, exists in the United States.
A pure factory
A entire lot of the cork produced in Portugal grows in the gently undulating hills and plains in the south of the country, in an frail agroforestry system is called montado. This savannah-fancy ecosystem combines cork, holm oaks and olive timber with pastures, grazing livestock, flowers and fallows.
“The soil in southern Portugal is amazingly heart-broken, there’s amazingly little rain and temperatures are very high in the summertime,” says Teresa Pinto-Correia, a professor on the University of Évora in Portugal specializing in rural landscapes and agricultural techniques. “However this fabricate of system is productive even when sources are scarce and prerequisites are complex.”
For centuries, locals devour preserved the montado due to cork equipped landowners with a provide of earnings. This mosaic of habitats supports hundreds of species, alongside side the Iberian lynx, the sphere’s most endangered wildcat, and the threatened Imperial eagle. One among the sphere’s oldest known cork oak timber, planted in 1783 in Águas de Moura, is is called “the whistler” due to so many birds run to its elephantine sprawling branches.
Iberian pigs feed on acorns and goats graze the interwoven pastures. Interspersing cork oak timber with animals and flowers can boost production and biodiversity, however furthermore compose soil, control erosion, defend water, combat desertification and sequester carbon, says Pinto-Correia.
While the cork forests can assist mitigate the outcomes of climate switch, they are furthermore increasingly extra in bother from it as drought and wildfires change into extra intense and extra frequent in the set up of living.
“The tree is adapted to the Mediterranean climate. The bark protects it from fire,” says forest engineer Conceição Santos Silva. “However for the first two years after cork is extracted, the timber are great extra at probability of wildfires due to they don’t devour this protection.”
But fires in cork groves, she says, remain uncommon due to of cautious human management. “The tree continually regenerates,” says Santos Silva.
As a slack-rising tree, the cork oak takes many years to fabricate coloration and fabricate appropriate quality cork. However in Coruche, of us soundless run by an primitive Portuguese saying: “Folks who care about their grandchildren plant cork oak timber.”