One of the most beautiful trees around has to be the olive with its silver evergreen leaves and knarled and knotted trunks.

A whole way of life has developed around the olive tree in the Mediterranean areas of Greece, Italy and Spain and the oil from the trees became a prized commodity that was used as currency and traded against other luxuries such as gold and wine. Spain became one of the major exporters of olive oil. Today Spain produces around 600,000 tons of oil and supplies about 40% of the world’s supply. There are around 200 million olive trees from Barcelona down to Huelva, although the majority are found in the provinces of Córdoba and Jaén. The trees are protected and it can take up to ten years for an olive tree to become fully productive. Mature trees fetch many hundreds of euros and large lorries are often seen transporting olive trees from one location to another.

In traditional olive groves, three different varieties were grafted onto one trunk, creating a three-pronged tree. This meant that the trees had to be planted quite far apart, leaving wide sections of land that were, in effect, wasted. A new technique was introduced about thirty years ago, using single trees. Trees could then be planted closer together, resulting in a more efficient use of land. Harvesting of the olives is very labour-intensive and it often involves whole families spending their weekends and any spare time, collecting the olives. This can be done by machines which are attached to tractors. The machines circle the trunk of the tree and the olives are shaken into a special catcher. The more traditional way is to surround the tree with nets and the olives are then shaken or pulled off using hands or a special rake. Harvesting usually takes place from November to March, depending on the area the trees are grown and the olives are taken to the mills within a day or two to keep down the oxidation and acidity.

The mills are run as cooperatives and they set the price for the olives. The olives are graded and payment can be either in cash or in olive oil. Most people prefer to have the oil as it is generally better value. The olives are washed before being crushed into a paste that is spread on woven nylon mats. They are then squeezed by a hydraulic press with the help of metal hammers and centrifuges. The liquid is separated from the paste, leaving a fibrous residue that is used in the making of soap or fertilizer. The oil is then separated from the liquid and is left to mature for several weeks. It is then graded and bottled, similar to wine production, but unlike wine, the olive oil’s quality is determined more by the production process than the actual raw material. For instance, if heat is added during milling, the amount of olive oil obtained per ton of olives, increases, but the quality drops. Olive oil is divided into different grades, the best grade being extra virgin olive oil. A panel of professional tasters is responsible for grading the oil and the international governing body in Spain is the International Olive Oil Council in Madrid. There are over a hundred varieties of olives and the only difference between green black and green olives is the time they take to pick.