Family: Oleaceae
Species: Olea europea L.
Common name: Olive or Ulivo
Etymology
The Greeks gave it the special name λαία, which the Latins rendered as olea.
Description
The olive tree is a characteristic plant of the Mediterranean regions and is cultivated in Italy for oil production. It has an irregular trunk, often twisted and decayed in older specimens. It bears upright branches and angular twigs, sometimes thorny in wild forms. The bark is grey and often covered with lichens.
The white and inconspicuous flowers are arranged in clusters in the axils of the leaves; they bloom from April to June and are called mignole. A notable characteristic of the olive tree is the annual alternation of flower and fruit production—a year of high olive yield is followed by a year of low productivity.
The leaves are persistent, opposite, and leathery, with an entire, often revolute margin. They are silvery green, hairless on the upper side, and lighter with a tomentose layer on the underside.
The fruit is an oily drupe, oval in shape. It is green at first and turns black when ripe. It consists of a “fleshy” part (pulp) that contains oil and a woody, wrinkled stone.
Habitat
It is presumed to be native to Asia Minor and Syria.
Properties and Uses
Olive cultivation has been a cornerstone of the Mediterranean economy since ancient times. Today, Italy is among the largest producers of olives in the world. Olives are primarily used for the extraction of oil, which is celebrated for its nutritional and medicinal properties. The very hard wood is used for cabinet-making, lathe work, and inlay.
Notes and Curiosities
The olive tree requires little water, although prolonged water shortages can cause serious damage, such as fruit drop and low yield. Severe frosts can destroy the entire aerial portion, leaving only the stump, and strong winds—especially when combined with low temperatures, excessive rainfall, and high humidity—can also be damaging.
One of the most remarkable aspects of the olive tree’s adaptability is its resistance to prolonged drought. In dry conditions, shoot growth ceases, the transpiring surface is reduced as some leaves fall, and water from the developing olives is reabsorbed.
The olive tree also performs valuable environmental functions by mitigating climate change. Olive stones are an excellent, economical, and ecological fuel, as the CO₂ emitted during combustion equals that released during natural decomposition. Thus, olives are an essential energy resource for countries that produce and export olive oil; in Madrid, this energy source is already in use, providing heat and hot water to several homes.
Among the Greeks, the olive tree was considered sacred to the goddess Athena; legend is that in her attempt to bless humanity, she planted her spear in the ground, and the first olive branch sprouted. The olive tree was so revered that anyone caught damaging it was punished with exile. At that time, the tree was not the cultivated olive but its wild progenitor. In Christian tradition, the olive branch symbolises peace and brotherhood.
The greatest concentration of olive trees in Lombardy is found in the lake area. On Lake Garda, olives are abundant and renowned for the high quality of their produce; among the myriad olive groves, one can observe numerous centuries-old plants that are the pride of the Benacense area.
The olive tree is used for ornamental purposes in the Heller garden. Near the rock garden, a sculptural specimen resembling a candelabra is surrounded by the bristly foliage of mountain pines and junipers, as well as the dense undergrowth of begonias and the highly scented Salvia microphylla.