VOA Special English

This is the VOA Special English Agriculture Report.

Some winemakers are turning to metal or plastic closures instead of cork
Cork is a light brown material harvested from the cork oak tree. Cork is lightweight, strong and resistant to water.

It is best known for keeping liquids from spilling. For thousands of years, people have used pieces of cork as closures for bottles.

Cork is made of small cells filled with air. This structure makes it elastic, so it can be pressed but later return to its full shape. It is said that no technology has been able to copy this unusual material exactly.

The cork oak tree is native to the western Mediterranean coast of Europe. The largest cork forests in the world are located in Portugal. In fact, Portugal produces more than half of the world's cork supply.

Cork oak trees have to be at least twenty-five years old before they are ready for harvest. Harvests only happen once every nine years.

Cork is gathered by skillfully cutting off the outer layer of the tree with special knives. The harvest weakens the tree temporarily, but it soon starts to grow a new layer of bark.

Next, the cork harvest is set out in the open for six months. Then, the cork is boiled in order to clean it and make it softer. After drying, the cork is ready to be cut.

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