Plugging the jug

Grape variety, place of origin and price. These are likely the main factors that determine which wine bottle lands in your shopping basket. But perhaps one more item is worth your consideration: the bottle’s cork, or lack thereof.

That’s because the wine industry’s rapid shift toward alternative means of bottle closure—like screw caps and synthetic plugs—has cast a cloud over the cork forests of Mediterranean Europe and North Africa.

There, the picturesque cork oak (Quercus suber) has been an integral part of the landscape and of the winemaking industry for centuries. But times are changing. While the stately trees still grow across some 5 million acres of arid countryside, the forests could become commercially obsolete within a decade, according to a 2006 report by World Wildlife Fund. Worse, the wine industry’s trend toward plastic and aluminum puts cork forests at risk of neglect, disease and fire.

Clearly, plastic and aluminum are shaping up to take over the market. Industry eyeballers report that natural corks still plug 70 percent of wine bottles globally, but WWF has predicted that by 2015 natural corks might seal as few as 5 percent of all wine bottles.

The negative socioeconomic effects will be felt most intensely in Portugal, where WWF launched its cork-oak landscapes program in 2005. Portugal produces 55 percent of the world’s corks and the industry employs more than 100,000 people, directly and indirectly.

The forests, which grow in relatively wild and remote regions of the south, provide habitat for a variety of wildlife. The Iberian lynx, Barbary deer and several raptors could suffer if the forests are allowed to go by the wayside. The trees also provide a natural barrier against desertification, already a problem in arid Mediterranean countries, and expected to grow worse with global warming and the simultaneous loss of protective vegetation.

In fact, experts predict desertification could spread south to north at a rate of 1 kilometer per year in southern Portugal. On the other hand, by protecting and even expanding Portugal’s cork forests, which currently total about one-third of the world’s acreage, desertification could be halted by 2020, according to WWF.

Angela Morgado, director of fundraising for WWF in Lisbon, says the organization has pleaded with the wine industry to support the cork economy and, in turn, help preserve the Mediterranean’s cork oaks.

The wine industry is not entirely convinced. Though corks have been the primary means for stopping wine bottles since the 1700s, synthetic stoppers and screw caps are cheaper. These products also preclude all risk of cork taint, a musty condition caused by improperly sterilized corks.

Cork taint is detectable even by amateur wine tasters and can make an infected wine virtually undrinkable, though the condition is relatively uncommon. At 58 Degrees & Holding Company, a wine shop on 18th Street in Sacramento, wine buyer Matthew Parker estimates that cork taint affects about 3 percent of bottles on his shelves.

Peter Webber, director of the Cork Quality Council, based in Forestville, Calif., believes tainted corks are even rarer than that. The council was founded in 1994; today roughly 80 percent of the corks used to stop American wine bottles have met Cork Quality Council standards. Webber estimates that cork taint now occurs in less than 1 percent of American wines.

The Forest Stewardship Council, which guards forests worldwide from abuse, has partnered with WWF to launch its own campaign for improved cork quality. By stamping all properly harvested and sterilized corks with an FSC seal of approval, winemakers and consumers could be better assured of an untainted wine while lending support to a sustainable future for the cork trade.

As dramatic as the trend sounds, the cork oak is not in any immediate danger of going extinct; the trees cannot be cut down, and makers of high-end port and sparkling wine may always tend toward natural corks for their bottles. In fact, producers of almost all high-end wines, especially red wines meant to age for years, will probably always prefer natural cork, says Parker.

“Most people who buy a $95 [cabernet] want a real cork in the bottle.”

The rest of us have a decision to make.