There are materials that do us good. Cork, from the tree that bears its name, is one of them, and it has been making a notable comeback in our lives for several years now. A renewable, 100% natural, ecological material, cork is not used only to seal our best vintages.
The possibilities offered by this natural material are many and its recycling concerns us all.
Cork: a bio-based, ancestral and innovative material
Cork comes from the bark of the cork oak (Quercus suber), a tree growing around the Mediterranean, mainly in Portugal, and also in Spain, Italy, France, Algeria and Morocco. It has been exploited primarily in Europe since the 17th century, but its qualities were known to the Romans and Greeks, who began making cork stoppers to better preserve wine or oil in amphorae (clay or resin stoppers having proved limited). It was Dom Pierre Pérignon, a Benedictine monk well known in the Champagne world, who is said to have popularised the use of cork.
Only the bark – referred to as suberified bark – is harvested. The tree is not cut down; only its very thick cork bark, up to 25 cm thick, is removed using a special axe, without damaging the cambium (living tissue beneath the cork).
The tree therefore remains alive. The cork oak is able to regenerate its bark after each harvest, allowing sustainable exploitation over decades. It is also fire-resistant: after each fire, frequent in these Mediterranean regions, it reconstitutes its bark… like a vegetal phoenix or a Terminator of the forests!
Properties and uses of cork
Given all its qualities, cork has many uses beyond making stoppers. It is a technical material widely used in the marine sector for boat decks because of its rot-resistant properties, in leather goods to make soles, shoes and small items, and as an accessory for numerous decorative items, jewellery and furniture. Light yet flexible, impermeable and insulating, attractive and watertight, it has also become a material of choice for thermal and acoustic insulation. The construction industry also uses it as an effective moisture barrier, accounting for 14% of its use. The wine industry remains its main outlet, representing 69% of consumption. It uses the protective and breathable qualities of cork as well as its density to produce high-quality stoppers.
Production and extraction
Portugal, the world’s leading cork exporter, is the undisputed leader in production (50% of the total). Suberaies, the name given to cork oak forests, account for nearly a quarter of the country’s woodlands, with a strong concentration in the Alentejo region. Portuguese cork represents 50% of world production. Portugal and Spain alone cover more than half of the exploited areas.
France produces a smaller but high-quality quantity, in specific areas (Corsica, Pyrénées-Orientales, Var and Landes). The cork sector in France produces 3 billion cork stoppers per year, out of 14 billion worldwide.
It must be understood that cork forests and plantations in Portugal and other Mediterranean countries are ecosystems in their own right. Cork cultivation relies on patient, extensive management of natural areas.
Furthermore, knowing that one tonne of cork absorbs 2 tonnes of CO2, and that global production is 300,000 tonnes per year, there is no need to do the maths to grasp the ecological value of this resource.
Extraction is done manually on the trunk when the tree is mature, at least 25 years old, by cutting or "lifting" the bark in large slabs. This is known as the debarking or lifting operation, carried out during the sap-rise period, from May to August. The first harvest produces so-called "male" cork, of lower quality, very thick and too hard, which will be sent for grinding. The bark renews naturally every 12 years approximately, on trees living on average 200 years. Each cork oak can thus be "scalped" around fifteen times in its life, producing so-called "female" cork, a noble, excellent-quality material. The cork slabs are air-dried for six months. Harvested cork has a very long shelf life, close to 100 years!
Cork recycling: an eco-friendly civic act within everyone's reach
France, as the world’s second-largest wine consumer, has a role to play.
A 100% plant-based product, cork stoppers can be recycled, but they are not classed as packaging. They therefore cannot be put in the yellow recycling bin. They must be dropped off at a local collection point. Household waste centres, town halls, supermarkets, organic shops, wine merchants and sometimes schools are all places where precious stoppers can be returned.
Fewer people know that many local, regional and national associations take part in collections to support charitable causes.
Options in France include Recycliege France, Planetliege (site of the French Cork Federation), and regional waste management organisations such as Smitcom.
Once collected, stoppers are sent to specialised recycling plants where they receive specific treatment. Ground, they become granules, which are then turned into boards or blocks to make other objects, including new stoppers, or used for energy recovery.
Avoid putting cork stoppers in the compost. Although biodegradable, they decompose rather slowly and, in that case, should not be bonded with glue or plastic, as some new commercial stoppers are. These must be thrown in the household refuse bin.
Sorting cork: a well-established process
Each year more than 60 million cork stoppers are recycled in France out of a consumption of 3 billion cork-sealed bottles.
In this area, prevention and information are major issues for this circular economy in order to promote a reflex in our daily habits: collect cork stoppers together at home rather than throwing them one by one in the bin.
At European level, there is a recycling code for cork, FOR51. It identifies products made from natural cork without any agglomerate or synthetic substitute.
Be careful not to confuse 100% cork stoppers with cork-look stoppers, which are agglomerates of synthetic materials and glue: these must not go in the yellow recycling bin!
Cork in the garden: why not consider it?
An insulating material in summer and winter, therefore thermoregulating… Now, doesn't that sound good for our plants? Cork stoppers are indeed one of the original but proven recycling options for our potted plants. For drainage or insulation against the cold, once cut into small pieces (yes, you have to get your hands a little dirty), 100% cork stoppers prove to be precious and economical allies, replacing clay pebbles. Placed under pots, they protect those left on terraces and balconies in winter.
Our cork stoppers can also find a second life and be upcycled very prettily and easily for Christmas. The natural material and colour of cork pair perfectly with pine cones and wood to decorate the home for the festive season. Keep it in mind!
Further reading…
Cork is venturing into the space industry! Discover this surprising article on the aeronautical potential of cork from a small French company.
Two websites to consult: Planète Liège and the Mediterranean Cork Institute (IML), which provide much more information on their comprehensive sites.
This video shows the cork stopper manufacturing process in a Portuguese factory.
There are materials that do us good. Cork, from the tree that bears its name, is one of them, and it has been making a notable comeback in our lives for several years now. A renewable, 100% natural, ecological material, cork is not used only to seal our best vintages.The possibilities offered by this natural […]
Planting trees to combat climate change may seem like a very simple solution. Fortunately, it is!
At a time when more trees are being cut down than planted, every tree you can plant in your garden will prove beneficial in various ways.
One of the causes of climate change is the excessive release of carbon dioxide (CO2), so the most obvious solution that comes to mind is to plant trees, as they absorb this CO2.
Why planting trees?
Plants in general, but trees in particular, have an incredible capacity to absorb CO2. This is simply a result of photosynthesis. The tree absorbs CO2 from the air and transforms it into carbon and oxygen. The oxygen is released into the air for our benefit, while the carbon is stored and gradually released. Forests thus represent the second largest carbon sink after the oceans.
But that's not all; trees are also useful for:
- regulating temperature and humidity: they are true living air conditioners;
- filtering wind and dust, thereby improving air quality;
- fixing certain pollutants such as pesticides or heavy metals;
- improving soil by adding biomass (wood, leaves...) and combating erosion.
Which trees to plant to combat climate change?
1) Native trees first
There are two huge advantages to planting native species:
- they are perfectly adapted to the climate and soil
- they nourish and provide shelter for local wildlife
The list of native trees is long, but here are a few examples:
- For the North: Field Maple, Glutinous Alder, Downy Birch, Common Hornbeam, Male Dogwood, Common Ash, Holly, Trembling Aspen, Field Elm...
- For the South: Strawberry Tree, Montpellier Maple, Corsican Alder, Chestnut, Olive, Holm Oak...
- For the mountains: Hop Hornbeam, Mountain Elm, Mountain Pine...
- For the Coast: Tamarisk, Sea Buckthorn, Bohemian Olive, Maritime Pine, Field Maple...
2) Natives, but not only...
Some natives are suffering from climate change while others, more exotic or southern species, seem to be making their way north. For instance, Pines, across all species, are suffering from repeated attacks by Pine Processionary caterpillars. Meanwhile, Common Beech, spruces, and even Pectinate Fir can no longer withstand our hot and dry summers. All these trees have also become less resistant to diseases.
On the other hand, some trees are seeing their original range shift. This is not surprising: it has always been the case! Plants grow where they thrive best. This is why we have issues with certain invasive exotic plants that turn out to be more suited than natives in some natural environments. Or the fact that oak forests are regaining ground over beech forests as they did... only two thousand years ago.
Some examples of trees that have adapted to climate change
- Holm Oak - Quercus ilex: once confined to the Mediterranean climate, it is now moving further north. It now thrives along the Atlantic coast up to Brittany and will continue its progression towards the centre.
- Turkey Oak - Quercus cerris: previously only found in the southeast of the country, it is now moving categorically north, even reaching Belgium...
- Pubescent Oak - Quercus pubescens: a species particularly adapted to drought that has been thriving in recent years.
- Montpellier Maple - Acer monspessulanum: often found in nature alongside Holm Oak, it is following the same trend, progressing up to Vendée.
- Flowering Ash - Fraxinus ornus: a cousin of Common Ash but significantly less sensitive to ash dieback, it is gradually moving away from its native Corsica and Maritime Alps to further north.
- Pride of India - Koelreuteria paniculata: native to China and Korea, this tree proves to be perfectly resistant to drought and urban pollution.
- Maritime Pine - Pinus pinaster: originally found around the Mediterranean and along the coast, it continues its spread westward and northward.
- Black Locust - Robinia pseudoacacia: this exotic tree is gradually becoming the "king of the forest". It withstands heat, drought, and flooding and is adapted to poor soils as it has the ability to fix nitrogen. It is thus gradually taking the place of other tree species.
For your information: the National Forestry Office is currently conducting trials of Bornmuller Fir (Abies bornmuelleriana) in forests, a species more suited to drought than Pectinate Fir. Meanwhile, in Belgium, trials are being conducted in forests with Turkey and Pubescent Oaks and even... Corsican Pines.
General characteristics of trees resistant to climate change
Trees that exhibit natural resistance to drought and high summer temperatures often share common characteristics:
- Small and numerous leaves: the larger the leaf, the more water evaporates. Small leaves are thus a result of adaptation to drought;
- Waxy and/or fuzzy foliage: if the leaf is thick or equipped with small hairs, it will retain water more effectively;
- Next, it is important to check the tree's region of origin: if it originates from the Scandinavian taiga, it is likely to suffer in summer... Conversely, mediterranean and central European species will be particularly well-suited.
In conclusion
Due to the accelerating climate changes in recent decades, we will need to reassess our approach regarding native species adapted to regions. Some, whose survival requires moisture and distinct seasons, will disappear in favour of less water-demanding species that do not require harsh winters. In any case, planting trees will be beneficial as long as we choose species that can thrive optimally with minimal care. So in conclusion: let’s plant trees!
To learn more
Some researchers express doubts about the effectiveness of tree planting to combat climate change. In reality, it is mainly the notion that CO2 is the sole culprit of climate change that they question, as well as the belief that we will (according to them) need even more agricultural land to feed the population. The ideal would also be to stop deforestation rather than just replanting a few trees here and there. If you wish to learn more and form your own opinion on the matter, read this article (in French): Forests: a solution to the climate crisis?
And if you haven't seen it yet, here are the main results of our survey on climate change and gardening.
Planting trees to combat climate change may seem like a very simple solution. Fortunately, it is! At a time when more trees are being cut down than planted, every tree you can plant in your garden will prove beneficial in various ways. One of the causes of climate change is the excessive release of carbon […]
