Cork Oak

What is the cork oak?

The cork oak, Quercus suber, is an evergreen Mediterranean oak with an unusual gift: it grows a thick, light, insulating outer bark, and it can lose that bark and grow it again. That is what makes cork a renewable material harvested from a living tree rather than a product of felling.

The bark exists for a reason that has nothing to do with us. In a landscape that burns, an insulating layer around the trunk is survival equipment. Fire passes, the crown may be scorched, and the tree resprouts. Everything about the cork oak points at fire, and that is why it is a founding species of open, grazed Mediterranean systems where other trees give way.

Harvesting follows the tree's own pace. A first stripping is possible only when the trunk has reached a certain girth, and afterwards the bark is taken again after roughly nine to twelve years, in Sardinia commonly ten. The work is done by hand with an axe in the warm season, and a badly cut tree is damaged for decades, which is why the craft matters as much as the timing.

Italy gave the species its own law remarkably early. Law 759 of 1956 regulates the cultivation, protection and use of the cork oak in detail: no first stripping before the trunk measures 60 centimetres around at 1.30 metres from the ground, no cork taken before it is nine years old, no felling even of trees that have stopped producing, and no thinning without authorisation. Sardinia added regional law 4 of 1994, which protects cork trees and cork woodlands as parts of the island's environment, landscape, economy and cultural heritage in the same sentence.

Sardinia carries the great majority of Italy's cork oak land. Of roughly 186,000 hectares nationally, about 83 per cent lies on the island, split between closed cork woodland and wooded pasture with cork oaks. Those figures come from the 2005 national forest inventory and the 2008 regional land use map and should be read with that date in mind. The centre of the cork economy is the Gallura in the north, not our own district.

How Terra Humana understands it

The cork oak is the clearest example we know of a tree that can be used without being consumed.

Nothing about it is taken by force. The bark is given back by the tree every decade, the trunk keeps standing, and a well tended cork oak can be harvested across a working life longer than any single person's. That is a different relationship with a plant than harvesting timber, and it is worth naming rather than assuming.

It also shows that protection and use are not opposites. Italian law forbids felling the cork oak while regulating its harvest in the same breath. The tree is worth more alive and productive than as wood, and the law simply wrote that down. For a foundation that argues for biodiversity inside working landscapes, this is a precedent, not an exception.

According to the official landscape survey, the original cover of the Ogliastra was cork oak on acid soils and holm oak on neutral to basic ground. Much of it was lost to fire, overgrazing and unsuitable tillage. Knowing which tree belonged where is the beginning of putting it back.