From Bark to Bottle—The Story of Cork
From Bark to Bottle—The Story of Cork
Can you imagine a tree bark that plays a crucial role in the making of engines, cricket balls, baseballs, and champagne—a bark that was used thousands of years ago by fishermen and elegant ladies alike and that has even been used in outer space? More amazing is the fact that this unique bark can fill all these needs without the tree being felled!
CORK is the outer layer of the bark produced by the cork oak tree. But this is no ordinary bark. It is light, fire resistant, and elastic.
The cork oak generously produces its resilient bark year after year. Unharvested, the bark can grow to be ten inches (25 cm) thick—a useful overcoat for protecting the tree against heat, cold, and forest fires. If harvesters strip the bark, the cork oak gradually grows another coating within about ten years.
Portugal provides about 55 percent of the worldwide cork production, Spain about 30 percent, and other countries (including Algeria, France, Italy, Morocco, and Tunisia) the remaining 15 percent. *
Multiple Uses
Romans and Greeks discovered that cork made ideal floats for fishing nets and could make a comfortable sole for sandals. Apparently, they also used cork stoppers for jars. Since it keeps its elastic property even at high temperatures, cork is ideal for engine gaskets. It is also an integral part of heat panels used on certain spaceships.
Because many homeowners appreciate both its appearance and its insulation properties, cork tiles have become popular for decorating walls and floors. Makers of sporting goods also find cork invaluable for the inner core of a baseball or the handle of a fishing rod. Of course, cork is perhaps best-known for its use as a stopper for bottles of wine and champagne.—See the box “The Ideal Stopper.”
Environmentally Friendly
A well-maintained cork forest offers proof that man can work in harmony with nature—harvesting its bounty without despoiling its riches. The old cork oaks beautify the countryside, provide shade and food for the cattle that graze beneath their boughs, and temper the harsh summer climate.
Several birds in danger of extinction—including the imperial eagle, the black vulture, and the black stork—depend on large cork oaks for suitable nesting sites. The endangered Iberian lynx also finds its last strongholds in forests of these oaks. Recently, the World Wildlife Fund stated that the survival of this species of lynx depends on the prosperity of the cork industry in Spain and Portugal.
So the next time you remove a cork from a bottle of wine, take a moment to appreciate it. You hold in your hand a natural, biodegradable, renewable object. And its use even serves to protect the environment. What more could you ask from a tree?
[Footnote]
^ par. 5 The cork oak grows in other parts of the world, but commercial production comes mainly from the Mediterranean region, where the cork oak grows naturally.
[Box/Picture on page 20]
“The Ideal Stopper”
Miguel Elena, director of the Institute for Cork, Wood and Charcoal, based in Extremadura, Spain, explains more about the use of cork as a stopper.
How effective is cork as a stopper?
I have seen corks removed from bottles that were over a hundred years old, and the wine had been effectively preserved! Cork is the ideal stopper.
How old should a cork oak be for its bark to be harvested for stoppers?
To produce a high-quality stopper, cork oak must be at least 50 years old, although the first harvest can be obtained 25 years after planting the acorn. Of course, few people are prepared to invest in a crop that will not make money for 50 years. In fact, I can’t think of any industry that has to wait so long before becoming profitable.
What is the life span of a cork oak?
A cork oak tree has a life span of about 200 years, and some specimens live much longer. The cork is harvested every nine years.
What is being done to maintain production of cork?
The European Union and our local regional government provide subsidies to encourage the planting of cork oaks. So in recent years we have planted acres of new cork forests and improved existing ones.
What recent developments have been made with regard to cork production?
During the past two decades, we have done a lot of research to identify the best acorns. And we work closely with other cork-producing countries to improve the product. We introduced a type of small handsaw that will enable cork strippers to remove the bark more efficiently, a task that has been done with axes for centuries.
[Picture on page 19]
After each stripping, the bark grows back
[Picture on page 19]
Skilled workers carefully remove the bark
[Picture on page 19]
Planks are stacked, ready for the next step
[Picture on page 19]
Top-quality corks are still punched by hand
[Picture on pages 18, 19]
Remnants and particles are collected and formed into agglomerated corks and other products
