Cork oaks have been exploited by humans for hundreds of years due to its valuable outer bark layer – the cork. Today, this raw material is used by several industries, from the production of wine stoppers to the provision of construction supplies and – more recently – the manufacturing of fashion items like bow ties, sunglasses and backpacks. But why is cork more sustainable than other well-established fashion alternatives?
#1 Harvesting cork does not kill trees
During cork harvesting, big rectangular planks of outer bark are carefully stripped from the trunks of cork oak trees (Quercus suber). The outer bark consists merely of layers of dead cells that protect the plant’s vital tissues, hence, although sometimes branches need to be removed in order to allow the extraction, this process is completely compatible with the maintenance of a healthy tree. In fact, after harvesting, cork will eventually start growing again to protect the plant from the surrounding environment. And within a decade, usually a cork oak tree already developed enough outer bark to be stripped again. So, unlike what happens when trees are cut down for wood, cork harvesting resembles more someone cutting their nails than a brutal murder.
Cork oak trees (Quercus suber) recently harvested for cork in a forest at Peneda-Gerês National Park (Portugal). Photo by Sofia Oliveira.
#2 Cork oak forests and savannas foster great biodiversity
Cork oaks can occur naturally in high-density forests or in savanna-like ecosystems. Both foster a great number of species and hold high value for wildlife conservation. Iberian imperial eagles (Aquila adalberti) and Iberian lynxes (Lynx pardinus) are only two examples of endangered species that call cork oak savannas their home. These savannas are the result of forest clearance as well as livestock grazing, which lead to a much sparse abundance of trees and shrubs. The neglect of such farming practices would allow vegetation to grow freely and cork oak savannas would slowly transform into shrublands. But too much farming is just as bad, since overharvesting and overgrazing would restrict the ability of cork oaks to regenerate. The bottom line is, in both scenarios, this human-shaped ecosystem would either be converted or degraded, and biodiversity would be lost. Obviously, the conservation of cork oak savannas depends upon a delicate balanced use by humans. But, how can our profit-driven society achieve such goal? With cork-base goods?! Actually, yes. The profitability of cork functions as an incentive for farmers to not forsake their savannas. Plus, overuse can be discouraged by attributing economic incentives to the ones producing cork through sustainable management! People often say money cannot buy happiness, but I think Iberian lynxes might disagree.
(1) Adult Iberian imperial eagle (Aquila adalberti). Photo by José Antonio Lagier Martin (CC BY 3.0 license). (2) Iberian lynx cub (Lynx pardinus). Photo by Iberian Lynx Ex-situ Conservation Program (CC BY 3.0 ES license).
#3 Cork oaks are climate change fighters
Cork oaks are capable of absorbing large quantities of CO2. In fact, it is estimated that cork oak savannas can absorb about the same quantity of CO2 as the mighty tropical forests. But, let me paint an even clearer picture for you: in a one-year period, a single cork oak savanna can absorb all CO2 emitted by 1 500 cars! Besides, cork oak trees can live up to 200 years, which means they can store this greenhouse gas for long periods of time, preventing it from being released into the atmosphere again. And if you think that extracting cork might hamper these trees ability to absorb and retain CO2, you are most definitely wrong. The effect is negligible. Is it just me or does it sound like Greta Thunberg needs a cork pencil case?
#4 Creating cork-based goods can be waste-free
Usually, manufacturing a product involves the generation of some sort of waste. Why does it matter? Well, undifferentiated trash is typically either incinerated or deposited in a landfill. Both disposal methods imply environmental damage, such as soil pollution and greenhouse emissions. While recycling waste is a better option, this process still consumes extra resources and releases greenhouse gases. As such, unlike my adorable idiot cousin who proudly takes two large bags full of unnecessary packaging to the recycling bin after shopping, we should support industries that generate the least amount of waste. And…guess what?! Since lots of different uses are now in place for industrial cork by-products (including energy production!), it all ends up being reused or valorized in some way. In other words, the manufacturing of cork-based products can be done without generating waste!
#5 Cork is a renewable resource
The cherry on top of the cake is that, thanks to the rare ability of cork oak trees to regrow outer bark throughout their lifetime, cork is considered a renewable resource!
In a nutshell, when you acquire cork-based fashion accessories from sustainable sources (e.g. FSC-certified cork), you are not just buying an eco-friendly product, you are also truly contributing to climate change mitigation and biodiversity conservation! Are cork goods the dream of every environmentalist, or what? Finally, let me address the pressing question popping into your head over and over again while reading this entire article: no, this post is not sponsored.
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