The Cork Oak and Wine, the Story of an Old Friendship

By Jose Luis Gallego, environmental communicator (@ecogallego) 

The Quercus genus includes the tree species most closely associated with the Mediterranean forest: oaks, holm oaks, gall oaks, kermes oaks, and cork oaks. These are indigenous trees, perfectly adapted to our climate, which once covered much of the Iberian Peninsula. In recent years, their numbers have decreased, giving way to other species that have been introduced for forest and timber exploitation.  

Much smaller than the oak and holm oak, the cork oak (Quercus suber) is a medium-sized tree with an open crown and wizened appearance. This is largely due to the rugged bark that covers its short gnarled trunk: cork, a material that humankind has used since ancient times. When the trees are used for cork production, their trunks are stripped bare. If the cork has been removed recently, the trunk has an orange tinge, gradually turning dark brown with the passage of time.  

The leaves are small, oval, and evergreen, with a smooth surface and margins, brilliant green on top, pale green on the bottom. It produces sweet acorn fruit (although less sweet than the holm oak) that provide a very nutritious food source for various forest animals: from dormice and wild boar to cranes and deer, making cork oak groves one of nature’s most abundant pantries. In meadowlands, livestock graze under their canopy and feed on the acorns, first and foremost the famed Iberian pig.  
 

Cork exploitation at the Alcornocales Nature Park, Cadiz (photo by Jose Luis Gallego) 

However, what these oaks are best known for is the production of cork, the bark which covers the trunk and protects the tree from the most inclement conditions, including forest fires. Cork harvesting does not harm the tree. In fact, removing the bark improves the health and development of the trees and is among the oldest farming traditions in rural Spain.  

This thousand-year-old activity keeps rural communities alive, generating over 100,000 direct jobs in the main cork-producing countries, including Spain, Portugal, Algeria, Morocco, Italy, France, and Tunisia. 

The cork industry, however, does more than stimulate the rural economy. It also contributes directly to the conservation of our biodiversity, because cork oak groves are among the most characteristic woodlands of the Mediterranean landscape, be it in meadows or wild forests. They are home to countless species of Iberian fauna, including some of the most endangered animals: the Spanish imperial eagle, black vulture, and Iberian lynx.  

Furthermore, the sustainable exploitation of cork oaks has a positive impact on other rural sectors such as handicrafts, food production, and rural tourism, providing an excellent example of the symbiosis between humans and nature, circular economy, and sustainable development. 
 

Cork is the bark of the cork oak (photo by Jose Luis Gallego) 

Finally, I would like to emphasize that few cultural, historical, and traditional connections run as deep as the one between the cork and wine sectors.  It is the story of an old and lasting friendship, which can be traced back to the dawn of our civilization and has been kept alive for centuries. 

Cork stoppers have preserved wine since time immemorial, resulting in one of the most characteristic, popular, and natural products of the cork industry. The name of this particular bark is inseparable from the wine world, synonymous with its most famous closure and the very act of opening a bottle: uncorking.   

Given the close connection between cork, wine, and nature, conservationists have spent years running awareness campaigns in support of the continued use of this 100% natural and recyclable material to seal wine bottles, a material whose exploitation does not harm the trees, but in fact contributes to their growth and the development of the rural communities that depend on them.