BBC: "It's not just a tree we are trying to protect here. It is a whole environment," says Antonio Ferreira, who has been a land owner and cork farmer in the Coruche district of Portugal for many years.
"The forest you see around you now has been like this for hundreds of years. It is meant to be this way".
Antonio points to the cork oaks whose roots hold the soil together in Portugal's increasingly extreme climate, where deluges can be followed by many weeks entirely without rain.
Not only is there none of the creeping desertification here which marks much of the southern Iberian peninsula these days, there is an abundance of life.
Between the oaks, wildflowers flourish, sustaining bees and honey production.
Some of the animal, bird and insect life is unique to the cork forest.
Mushrooms are harvested that sprout from the root fibres. Livestock like sheep and pigs feast on acorns in the autumn and in turn help fertilise the soil.
It being harvest day, these woods are buzzing with people and tractors.
It is exactly nine years since the trees were stripped of the bark that is the main source of income for landowners.
And the cork has grown back, several centimetres thick and ready for collecting.
Farmers do not risk letting anyone loose on these trees with a sharpened axe. The men putting carefully placed cuts in the bark, and peeling back people-sized chunks of outer tree trunk, have been doing this job for years.
"It's like cutting cloth for dress-making", says Mr Ferreira.
Conceicao Silva, who works as a forest engineer for the organisation overseeing environmental standards in the industry, adds: "Bring the axe down too hard on the branch and permanent damage could be done, which will rule out generations of future harvesting.
"If it's properly managed, what we are looking at here is the ultimate sustainable resource." Urging Vintners to Put a Cork in It >>> By Paul Henley, BBC News, Portugal | September 18, 2008
BBC Audio: Does the screw cap spell the end for Portugal’s cork production? >>>
BBC video: Once every nine years: How cork is harvested >>>
