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Cork: A Natural Choice

Although pulling a cork from a wine bottle is about as familiar and beloved a ritual as there is to a wine lover, not many of us stop to think about where these ingenious little bottle stoppers come from. Unlike money, cork really does grow on trees, made from the bark of what’s known as the Cork Oak or Quercus Suber L. Thriving in Mediterranean regions where hot, dry summer climates provide an ideal habitat, cork tree forests can be found predominantly in southern Portugal, Spain and northern Africa, where it’s estimated they cover over 6 million acres. And although cork oak trees grow in many places outside the Mediterranean, Portugal and Spain account for over 80% of the world’s cork production.

The use of corks as bottle stoppers dates back to ancient Egypt, although it wasn’t until the 17th century that they were commonly used for this purpose. Dom Perignon, the Benedictine monk credited with “discovering” champagne, wanted to develop something better than the wooden stoppers that up until then had been used as a closure. They had an annoying habit of popping out of the bottle! The innovative monk successfully substituted a stopper made of cork, and it wasn’t long before cork was used by winemakers all over Europe.

Like grapevines and vineyards, cork trees and the forests they’re grown in require a long term investment on the part of their owners and caretakers. It takes 25 years for a cork tree to be considered mature enough for “stripping” without harming the tree, and another 15-20 years before the bark is considered suitable for cork stoppers. Cork from the first and second stripping is often used for flooring and decorative home products.

Removing the thick, rugged cork bark is always done by hand (with a special axe designed for this purpose) in the spring or summer when the tree is in a growth phase and the bark is easily separated from the trunk. Cork trees can only be stripped every 9-12 years (regulations regarding the length of this cycle vary according to region) to ensure the health of the tree. With an expected life cycle of 150-250 years, that means each tree can be harvested approximately 12-18 times.

Given the longevity of a cork oak tree and its economic viability, it’s only logical that the cork industry is populated with family-owned companies, many having been in business for over a century. And as land has passed from generation to generation, the industry has maintained a forward-looking approach, increasingly emphasizing sustainable forest management and practices. As a result, cork oak forests are some of the best examples of sustainable agroforestry in the world.

There are many parallels between the wine and cork worlds: they’re both rooted in agriculture, they attract small family businesses that are passionate about quality, and they require long-term vision and a protective and sustainable approach to the environment. No wonder then that cork, a natural product with properties of flexibility, compressibility and biodegradability, is still considered by the vast majority of winemakers to be the optimum material for protecting and preserving the precious contents of a wine bottle.