The olive, known by the botanical name
"European olive", is a species of small tree in the family Oleaceae,
found in the
to the Levant, the
Arabian Peninsula, and southern
as far east as China, as well as
and Réunion. The species is cultivated in many
places and considered naturalized in all the countries of the
coast, as well as in Argentina, Saudi Arabia, Java,
Norfolk Island, California, and Bermuda.
europeana sylvestris is a subspecies that corresponds to a
smaller tree bearing noticeably smaller fruit.
The olive's fruit, also called the olive, is of major agricultural
importance in the
region as the source of olive oil; it
is one of the core ingredients in
cuisine. The tree and
its fruit give their name to the plant family, which also includes
species such as lilacs, jasmine, Forsythia, and the true ash trees
(Fraxinus). The word derives from
ŏlīva ("olive fruit", "olive
tree"; "olive oil" is ŏlĕum) a borrowing from the Greek
ἐλαία (elaía, "olive fruit", "olive tree") and ἔλαιον
(élaion, "olive oil") in the archaic form *ἐλαίϝα. The
oldest attested forms of the Greek words are the Mycenaean
𐀁𐀨𐀷, e-ra-wa, and 𐀁𐀨𐀺, e-ra-wo or 𐀁𐁉𐀺,
e-rai-wo, written in the
syllabic script. The word
"oil" in multiple languages ultimately derives from the name of this
tree and its fruit.
3.2 Outside the Mediterranean
4 Symbolic connotations
4.1 Ancient Israel and Hebrew Bible
4.2 Ancient Greece
4.3 Ancient Rome
4.4 New Testament
5 Oldest known trees
6.1 Table olives
6.2 Traditional fermentation and curing
7.1 Growth and propagation
7.2 Pests, diseases, and weather
7.3 As an invasive species
7.4 Harvest and processing
8 Global production
10 Allergenic potential
12 See also
14 External links
The olive tree,
Olea europaea, is an evergreen tree or shrub native to
the Mediterranean, Asia, and Africa. It is short and squat, and rarely
exceeds 8–15 m (26–49 ft) in height. 'Pisciottana', a
unique variety comprising 40,000 trees found only in the area around
Pisciotta in the
Campania region of southern
Italy often exceeds this,
with correspondingly large trunk diameters. The silvery green leaves
are oblong, measuring 4–10 cm (1.6–3.9 in) long and
1–3 cm (0.39–1.18 in) wide. The trunk is typically
gnarled and twisted.
The small, white, feathery flowers, with ten-cleft calyx and corolla,
two stamens, and bifid stigma, are borne generally on the previous
year's wood, in racemes springing from the axils of the leaves.
The fruit is a small drupe 1–2.5 cm (0.39–0.98 in) long,
thinner-fleshed and smaller in wild plants than in orchard cultivars.
Olives are harvested in the green to purple stage. Canned black
olives have often been artificially blackened (see below on
processing) and may contain the chemical ferrous gluconate to improve
Olea europaea contains a seed commonly referred to
in American English as a pit or a rock, and in British English as a
The six natural subspecies of
Olea europaea are distributed over a
Olea europaea subsp. europaea (
O. e. subsp. cuspidata (from South
Africa throughout East Africa,
Arabia to South West China)
O. e. subsp. guanchica (Canaries)
O. e. subsp. cerasiformis (Madeira)
O. e. subsp. maroccana (Morocco)
O. e. subsp. laperrinei (Algeria, Sudan, Niger)
The subspecies O. e. maroccana and O. e. cerasiformis are respectively
hexaploid and tetraploid.
Wild growing forms of the olive are sometimes treated as the species
Main article: List of olive cultivars
Hundreds of cultivars of the olive tree are known. An olive's
cultivar has a significant impact on its colour, size, shape, and
growth characteristics, as well as the qualities of olive oil.
Olive cultivars may be used primarily for oil, eating, or both. Olives
cultivated for consumption are generally referred to as table
Since many olive cultivars are self-sterile or nearly so, they are
generally planted in pairs with a single primary cultivar and a
secondary cultivar selected for its ability to fertilize the primary
one. In recent times, efforts have been directed at producing hybrid
cultivars with qualities such as resistance to disease, quick growth,
and larger or more consistent crops.
Fossil evidence indicates the olive tree had its origins some 20–40
million years ago in the
Oligocene region corresponding to
Mediterranean Basin. The olive plant later was
first cultivated some 7,000 years ago in Mediterranean
The edible olive seems to have coexisted with humans for about 5,000
to 6,000 years, going back to the early
Bronze Age (3150 to 1200 BC).
Its origin can be traced to the
Levant based on written tablets, olive
pits, and wood fragments found in ancient tombs. At least one
cookbook writer notes that the most ancient evidence of olive
cultivation is found in Lebanon, Syria, Palestine, and Crete.
The immediate ancestry of the cultivated olive is unknown. O. europaea
may have arisen from O. chrysophylla in northern tropical
was introduced into the countries of the
Mediterranean Basin via Egypt
Crete or the Levant, Tunisia, and
Olea pollen has been found in Macedonia and other
places around the Mediterranean, indicating that this genus is an
original element of the
Mediterranean flora. Fossilized leaves of Olea
were found in the palaeosols of the volcanic Greek island of Santorini
(Thera) and were dated about 37,000 BP. Imprints of larvae of olive
whitefly Aleurolobus (Aleurodes) olivinus were found on the leaves.
The same insect is commonly found today on olive leaves, showing that
the plant-animal co-evolutionary relations have not changed since that
time. Other leaves found on the same island are dated back to
60,000 BP, making them the oldest known olives from the
As far back as 3000 BC, olives were grown commercially in Crete; they
may have been the source of the wealth of the Minoan civilization.
Outside the Mediterranean
Olives are not native to the Americas. Spanish colonists brought the
olive to the New World, where its cultivation prospered in present-day
Peru and Chile. The first seedlings from
Spain were planted in
Antonio de Rivera in 1560.
Olive tree cultivation quickly spread along
the valleys of South America's dry Pacific coast where the climate was
similar to the Mediterranean. Spanish missionaries established the
tree in the 18th century in California. It was first cultivated at
Mission San Diego de Alcalá
Mission San Diego de Alcalá in 1769 or later around 1795. Orchards
were started at other missions, but in 1838, an inspection found only
two olive orchards in California. Cultivation for oil gradually became
a highly successful commercial venture from the 1860s onward. In
Japan, the first successful planting of olive trees happened in 1908
on Shodo Island, which became the cradle of olive cultivation. An
estimated 865 million olive trees are in the world today (as of 2005),
and the vast majority of these are found in
with traditionally marginal areas accounting for no more than 25% of
olive-planted area and 10% of oil production.
See also: Peace symbols
Olive oil has long been considered sacred. The olive branch was often
a symbol of abundance, glory, and peace. The leafy branches of the
olive tree were ritually offered to deities and powerful figures as
emblems of benediction and purification, and they were used to crown
the victors of friendly games and bloody wars. Today, olive oil is
still used in many religious ceremonies. Over the years, the olive has
also been used to symbolize wisdom, fertility, power, and purity.
Ancient Israel and Hebrew Bible
The olive was one of the main elements in ancient Israelite cuisine.
Olive oil was used for not only food and cooking, but also lighting,
sacrificial offerings, ointment, and anointment for priestly or royal
The olive tree is one of the first plants mentioned in the Hebrew
Bible (the Christian Old Testament), and one of the most significant.
An olive branch was brought back to
Noah by a dove to demonstrate that
the flood was over (Book of Genesis, 8:11). The olive is listed in
Deuteronomy 8:8 as one of the seven species that are noteworthy
products of the Land of Israel.
The ancient Greeks smeared olive oil on their bodies and hair as a
matter of grooming and good health.
Olive oil was used to anoint kings and athletes in ancient Greece. It
was burnt in the sacred lamps of temples and was the "eternal flame"
of the original Olympic games. Victors in these games were crowned
with its leaves.
In Homer's Odyssey,
Odysseus crawls beneath two shoots of olive that
grow from a single stock, and in the Iliad, (XVII.53ff) is a
metaphoric description of a lone olive tree in the mountains, by a
spring; the Greeks observed that the olive rarely thrives at a
distance from the sea, which in
Greece invariably means up mountain
slopes. Greek myth attributed to the primordial culture-hero Aristaeus
the understanding of olive husbandry, along with cheese-making and
Olive was one of the woods used to fashion the most
primitive Greek cult figures, called xoana, referring to their wooden
material; they were reverently preserved for centuries. It was
purely a matter of local pride that the Athenians claimed that the
olive grew first in Athens. In an archaic Athenian foundation
Athena won the patronship of
Poseidon with the gift
of the olive. According to the fourth-century BC father of botany,
Theophrastus, olive trees ordinarily attained an age around 200
years, he mentions that the very olive tree of
Athena still grew
on the Acropolis; it was still to be seen there in the second century
AD; and when Pausanias was shown it, c. 170 AD, he reported
"Legend also says that when the Persians fired
Athens the olive was
burnt down, but on the very day it was burnt it grew again to the
height of two cubits." Indeed, olive suckers sprout readily from
the stump, and the great age of some existing olive trees shows that
it was perfectly possible that the olive tree of the
to the Bronze Age. The olive was sacred to
Athena and appeared on the
Theophrastus, in On the Causes of Plants, does not give as systematic
and detailed an account of olive husbandry as he does of the vine, but
he makes clear (in 1.16.10) that the cultivated olive must be
vegetatively propagated; indeed, the pits give rise to thorny,
wild-type olives, spread far and wide by birds.
how the bearing olive can be grafted on the wild olive, for which the
Greeks had a separate name, kotinos. In his Enquiry into Plants
(2.1.2–4) he states that the olive can be propagated from a piece of
the trunk, the root, a twig, or a stake.
Roman fresco of a woman with red hair wearing a garland of olives,
from Herculaneum, made sometime before the city's destruction in 79 AD
Mount Vesuvius (which also destroyed Pompeii).
According to Pliny the Elder, a vine, a fig tree, and an olive tree
grew in the middle of the Roman Forum; the latter was planted to
provide shade (the garden plot was recreated in the 20th century).
The Roman poet
Horace mentions it in reference to his own diet, which
he describes as very simple: "As for me, olives, endives, and smooth
mallows provide sustenance."
Lord Monboddo comments on the olive
in 1779 as one of the foods preferred by the ancients and as one of
the most perfect foods.
Storing olives on Dere Street; Tacuinum Sanitatis, 14th century,
Vitruvius describes of the use of charred olive wood in tying together
walls and foundations in his De Architectura:
The thickness of the wall should, in my opinion, be such that armed
men meeting on top of it may pass one another without interference. In
the thickness there should be set a very close succession of ties made
of charred olive wood, binding the two faces of the wall together like
pins, to give it lasting endurance. For that is a material which
neither decay, nor the weather, nor time can harm, but even though
buried in the earth or set in the water it keeps sound and useful
forever. And so not only city walls but substructures in general and
all walls that require a thickness like that of a city wall, will be
long in falling to decay if tied in this manner.
Mount of Olives
Mount of Olives east of
Jerusalem is mentioned several times in
the New Testament. The Allegory of the
Tree in St. Paul's
Epistle to the Romans
Epistle to the Romans refers to the scattering and gathering of
Israel. It compares the
Israelites to a tame olive tree and the
Gentiles to a wild olive branch. The olive tree itself, as well as
olive oil and olives, play an important role in the Bible.
The olive tree and olive oil are mentioned seven times in the
Quran, and the olive is praised as a precious fruit.
and olive-oil health benefits have been propounded in Prophetic
Muhammad is reported to have said: "Take oil of olive and
massage with it – it is a blessed tree" (Sunan al-Darimi, 69:103).
Olives are substitutes for dates (if not available) during Ramadan
fasting, and olive tree leaves are used as incense in some Muslim
Oldest known trees
Olive trees in the groves around the
Mediterranean Sea are centuries
old, with some dated to 2000 years. The olive tree on the island of
Istria in Croatia, has a radiocarbon dating age of
about 1,600 years. It still gives fruit (about 30 kg or
66 lb per year), which is made into olive oil.
An olive tree in west Athens, named "Plato's
Olive Tree", is thought
to be a remnant of the grove where Plato's Academy was situated,
making it an estimated 2,400 years old. The tree comprised a
cavernous trunk from which a few branches were still sprouting in
1975, when a traffic accident caused a bus to uproot it. Following
that, the trunk was preserved and displayed in the nearby Agricultural
University of Athens. In 2013, it was reported that the remaining part
of the trunk was uprooted and stolen, allegedly to serve as firewood.
A supposedly older tree, the "
Peisistratos Tree", is located by the
banks of the Cephisus River, in the municipality of Agioi Anargyroi,
and is said to be a remnant of an olive grove that was planted by
Peisistratos in the sixth century BC.
Numerous ancient olive trees also exist near
Pelion in Greece. The
age of an olive tree in Crete, the Finix Olive, is claimed to be over
2,000 years old; this estimate is based on archaeological
evidence around the tree. The olive tree of Vouves, also in Crete,
has an age estimated between 2000 and 4000 years. An olive tree
called Farga d'Arió in Ulldecona, Catalonia, Spain, has been dated
(with laser-perimetry methods) as being 1,701 years old, estimating
that it was planted when
Constantine the Great
Constantine the Great was Roman emperor.
Some Italian olive trees are believed to date back to Ancient Rome
(8th century BC to 5th century AD), although identifying progenitor
trees in ancient sources is difficult. A tree located in Santu Baltolu
di Carana, in the municipality of
Luras in Sardinia, Italy, is
respectfully named in Sardinian as the Ozzastru by the islanders, and
is claimed to be between 3,000 and 4,000 years old according to
different studies. Several other trees of about 1,000
years old are within the same garden. The 15th-century trees of Olivo
della Linza, at Alliste in the
Province of Lecce
Province of Lecce in
Apulia on the
Italian mainland, were noted by Bishop Ludovico de Pennis during his
pastoral visit to the Diocese of Nardò-Gallipoli in 1452.
The town of Bshaale,
Lebanon claims to have the oldest olive trees in
the world (4000 BC for the oldest), but no scientific study supports
these claims. Other trees in the towns of
Amioun appear to be at least
1,500 years old.
Throughout Israel and Palestine, dozens of ancient olive trees are
found with estimated ages of 1,600–2,000 years; however, these
estimates could not be supported by current scientific practices.
Ancient trees include two giant olive trees in Arraba and five trees
in Deir Hanna, both in the
Galilee region, which have been determined
to be over 3,000 years old, although no available data support the
credibility of the study that produced these age estimates, and as
such, the 3000 years age estimate can not be considered valid. All
seven trees continue to produce olives.
Several trees in the
Garden of Gethsemane
Garden of Gethsemane (from the Hebrew words gat
shemanim or olive press) in
Jerusalem are claimed to date back to the
purported time of Jesus. A study conducted by the National
Research Council of
Italy in 2012 used carbon dating on older parts of
the trunks of three trees from Gethsemane and came up with the dates
of 1092, 1166, and 1198 AD, while DNA tests show that the trees were
originally planted from the same parent plant. According to
molecular analysis, the tested trees showed the same allelic profile
at all microsatellite loci analyzed which furthermore may indicate
attempt to keep the lineage of an older species intact. However,
Bernabei writes, “All the tree trunks are hollow inside so that the
central, older wood is missing . . . In the end, only three from a
total of eight olive trees could be successfully dated. The dated
ancient olive trees do, however, not allow any hypothesis to be made
with regard to the age of the remaining five giant olive trees.”
Babcox concludes, “The roots of the eight oldest trees are possibly
much older. Visiting guides to the garden often state that they are
two thousand years old.”
Bidni olive trees, which have been confirmed
through carbon dating, have been protected since 1933, and are
also listed in UNESCO's Database of National Cultural Heritage
Laws. In 2011, after recognising their historical and landscape
value, and in recognition of the fact that "only 20 trees remain from
40 at the beginning of the 20th century", Maltese authorities
declared the ancient
Bidni olive grove at Bidnija, limits of Mosta, as
Tree Protected Area, in accordance with the provisions of the Trees
and Woodlands Protection Regulations, 2011, as per Government Notice
Canneto Sabino, Italy
Karystos, Euboia, Greece
Olive oil and
The olive tree,
Olea europaea, has been cultivated for olive oil, fine
wood, olive leaf, and the olive fruit. About 90% of all harvested
olives are turned into oil, while about 10% are used as table
olives. The olive is one of the "trinity" or "triad" of basic
Mediterranean cuisine, the other two being wheat for
bread, pasta, and couscous, and the grape for wine.
Olives in a plastic cup
Table olives are classified by the IOC into three groups according to
the degree of ripeness achieved before harvesting:
Green olives are picked when they have obtained full size, but before
the ripening cycle has begun; they are usually shades of green to
Semiripe or turning-colour olives are picked at the beginning of the
ripening cycle, when the colour has begun to change from green to
multicolour shades of red to brown. Only the skin is coloured, as the
flesh of the fruit lacks pigmentation at this stage, unlike that of
Black olives or ripe olives are picked at full maturity when fully
ripe. They are found in assorted shades of purple to brown to
Traditional fermentation and curing
An olive vat room used for curing
Raw or fresh olives are naturally very bitter; to make them palatable,
olives must be cured and fermented, thereby removing oleuropein, a
bitter phenolic compound that can reach levels of 14% of dry matter in
young olives. In addition to oleuropein, other phenolic compounds
render freshly picked olives unpalatable and must also be removed or
lowered in quantity through curing and fermentation. Generally
speaking, phenolics reach their peak in young fruit and are converted
as the fruit matures. Once ripening occurs, the levels of
phenolics sharply decline through their conversion to other organic
products which render some cultivars edible immediately. One
example of an edible olive native to the island of
Thasos is the
throubes black olive, which when allowed to ripen in sun, shrivel, and
fall from the tree, is edible.
The curing process may take from a few days, with lye, to a few months
with brine or salt packing. With the exception of
and salt-cured olives, all methods of curing involve a major
fermentation involving bacteria and yeast that is of equal importance
to the final table olive product. Traditional cures, using the
natural microflora on the fruit to induce fermentation, lead to two
important outcomes: the leaching out and breakdown of oleuropein and
other unpalatable phenolic compounds, and the generation of favourable
metabolites from bacteria and yeast, such as organic acids,
probiotics, glycerol, and esters, which affect the sensory properties
of the final table olives. Mixed bacterial/yeast olive
fermentations may have probiotic qualities.
Lactic acid is the
most important metabolite, as it lowers the pH, acting as a natural
preservative against the growth of unwanted pathogenic species. The
result is table olives which can be stored without refrigeration.
Fermentations dominated by lactic acid bacteria are, therefore, the
most suitable method of curing olives. Yeast-dominated fermentations
produce a different suite of metabolites which provide poorer
preservation, so they are corrected with an acid such as citric acid
in the final processing stage to provide microbial stability.
The many types of preparations for table olives depend on local tastes
and traditions. The most important commercial examples are:
Spanish or Sevillian type (olives with fermentation): Most commonly
applied to green olive preparation, around 60% of all the world's
table olives are produced with this method. Olives are soaked in
lye (dilute NaOH, 2–4%) for 8–10 hours to hydrolyse the
oleuropein. They are usually considered "treated" when the lye has
penetrated two-thirds of the way into the fruit. They are then washed
once or several times in water to remove the caustic solution and
transferred to fermenting vessels full of brine at typical
concentrations of 8–12% NaCl. The brine is changed on a regular
basis to help remove the phenolic compounds.
Fermentation is carried
out by the natural microbiota present on the olives that survive the
lye treatment process. Many organisms are involved, usually reflecting
the local conditions or "Terroir" of the olives. During a typical
fermentation gram-negative enterobacteria flourish in small numbers at
first, but are rapidly outgrown by lactic acid bacteria species such
as Leuconostoc mesenteroides, Lactobacillus plantarum, Lactobacillus
brevis and Pediococcus damnosus. These bacteria produce lactic acid to
help lower the pH of the brine and therefore stabilize the product
against unwanted pathogenic species. A diversity of yeasts then
accumulate in sufficient numbers to help complete the fermentation
alongside the lactic acid bacteria. Yeasts commonly mentioned include
the teleomorphs Pichia anomala, Pichia membranifaciens, Debaryomyces
hansenii and Kluyveromyces marxianus. Once fermented, the olives
are placed in fresh brine and acid corrected, to be ready for market.
Sicilian or Greek type (olives with fermentation): Applied to green,
semiripe and ripe olives, they are almost identical to the Spanish
type fermentation process, but the lye treatment process is skipped
and the olives are placed directly in fermentation vessels full of
brine (8–12% NaCl). The brine is changed on a regular basis to help
remove the phenolic compounds. As the caustic treatment is avoided,
lactic acid bacteria are only present in similar numbers to yeast and
appear to be outcompeted by the abundant yeasts found on untreated
olives. As very little acid is produced by the yeast fermentation,
lactic, acetic, or citric acid is often added to the fermentation
stage to stabilize the process.
Picholine or directly-brined type (olives with fermentation): Applied
to green, semiripe, or ripe olives, they are soaked in lye typically
for longer periods than Spanish style (e.g. 10–72 hours) until the
solution has penetrated three-quarters of the way into the fruit. They
are then washed and immediately brined and acid corrected with citric
acid to achieve microbial stability.
Fermentation still occurs carried
out by acidogenic yeast and bacteria, but is more subdued than other
methods. The brine is changed on a regular basis to help remove the
phenolic compounds and a series of progressively stronger
concentrations of salt are added until the product is fully stabilized
and ready to be eaten.
Water-cured type (olives with fermentation): Applied to green,
semiripe, or ripe olives, these are soaked in water or weak brine and
this solution is changed on a daily basis for 10–14 days. The
oleuropein is naturally dissolved and leached into the water and
removed during a continual soak-wash cycle.
Fermentation takes place
during the water treatment stage and involves a mixed yeast/bacteria
ecosystem. Sometimes, the olives are lightly cracked with a hammer or
a stone to trigger fermentation and speed up the fermentation process.
Once debittered, the olives are brined to concentrations of 8–12%
NaCl and acid corrected, and are then ready to eat.
Salt-cured type (olives with minor fermentation): Applied only to ripe
olives, they are usually produced in Morocco, Turkey, and other
Mediterranean countries. Once picked, the olives are
vigorously washed and packed in alternating layers with salt. The high
concentrations of salt draw the moisture out of olives, dehydrating
and shriveling them until they look somewhat analogous to a raisin.
Once packed in salt, fermentation is minimal and only initiated by the
most halophilic yeast species such as Debaryomyces hansenii. Once
cured, they are sold in their natural state without any additives.
So-called Oil-cured olives are cured in salt, and then soaked in
California or "artificial ripening" type (olives without
fermentation): Applied to green and semiripe olives, they are placed
in lye and soaked. Upon their removal, they are washed in water
injected with compressed air. This process is repeated several times
until both oxygen and lye have soaked through to the pit. The
repeated, saturated exposure to air oxidises the skin and flesh of the
fruit, turning it black in an artificial process that mimics natural
ripening. Once fully oxidised or "blackened", they are brined and acid
corrected and are then ready for eating.
Olive wood is very hard and is prized for its durability, colour, high
combustion temperature, and interesting grain patterns. Because of the
commercial importance of the fruit, and the slow growth and relatively
small size of the tree, olive wood and its products are relatively
expensive. Common uses of the wood include: kitchen utensils, carved
wooden bowls, cutting boards, fine furniture, and decorative items.
The yellow or light greenish-brown wood is often finely veined with a
darker tint; being very hard and close-grained, it is valued by
Potential distribution of olive tree over the
The earliest evidence for the domestication of olives comes from the
Chalcolithic period archaeological site of Teleilat Ghassul in what is
today modern Jordan. Farmers in ancient times believed that olive
trees would not grow well if planted more than a certain distance from
Theophrastus gives 300 stadia (55.6 km or 34.5 mi)
as the limit. Modern experience does not always confirm this, and,
though showing a preference for the coast, they have long been grown
further inland in some areas with suitable climates, particularly in
Mediterranean (Iberia, northwest Africa) where
winters are mild.
Olive plantation in Andalucía, Spain
Olives are now cultivated in many regions of the world with
Mediterranean climates, such as South Africa, Chile, Peru, Australia,
California and in areas with temperate climates such as New
Zealand, under irrigation in the Cuyo region in
Argentina which has a
desert climate. They are also grown in the Córdoba Province,
Argentina, which has a temperate climate with rainy summers and dry
winters (Cwa). The climate in
Argentina changes the external
characteristics of the plant but the fruit keeps its original
features. The northernmost olive grove is placed in Anglesey, an
island off the north west coast of Wales, in the United Kingdom:
but it is too early to say if the growing will be successful, having
been planted in 2006.
Olives at a market in Toulon, France
Growth and propagation
Olive trees on Thassos, Greece
Olive trees show a marked preference for calcareous soils, flourishing
best on limestone slopes and crags, and coastal climate conditions.
They grow in any light soil, even on clay if well drained, but in rich
soils, they are predisposed to disease and produce poorer oil than in
poorer soil. (This was noted by Pliny the Elder.) Olives like hot
weather and sunny positions without any shade, while temperatures
below −10 °C (14 °F) may injure even a mature tree. They
tolerate drought well, due to their sturdy and extensive root systems.
Olive trees can live for several centuries and can remain productive
for as long if they are pruned correctly and regularly.
Only a handful of olive varieties can be used to cross-pollinate.
'Pendolino' olive trees are partially self-fertile, but pollenizers
are needed for a large fruit crop. Other compatible olive tree
pollenizers include 'Leccino' and 'Maurino'. 'Pendolino' olive trees
are used extensively as pollenizers in large olive tree groves.
Phenological development of olive flowering, following BBCH standard
scale. a-50, b-51, c-54, d-57, (<15% open flowers); f-65, (>15%
open flowers); g-67, (<15% open flowers); h-68.
Olives are propagated by various methods. The preferred ways are
cuttings and layers; the tree roots easily in favourable soil and
throws up suckers from the stump when cut down. However, yields from
trees grown from suckers or seeds are poor; they must be budded or
grafted onto other specimens to do well. Branches of various
thickness cut into lengths around 1 m (3.3 ft) planted
deeply in manured ground soon vegetate. Shorter pieces are sometimes
laid horizontally in shallow trenches and, when covered with a few
centimetres of soil, rapidly throw up sucker-like shoots. In Greece,
grafting the cultivated tree on the wild tree is a common practice. In
Italy, embryonic buds, which form small swellings on the stems, are
carefully excised and planted under the soil surface, where they soon
form a vigorous shoot.
The olive is also sometimes grown from seed. To facilitate
germination, the oily pericarp is first softened by slight rotting, or
soaked in hot water or in an alkaline solution.
In situations where extreme cold has damaged or killed the olive tree,
the rootstock can survive and produce new shoots which in turn become
new trees. In this way, olive trees can regenerate themselves. In
Tuscany in 1985, a very severe frost destroyed many productive, and
aged, olive trees and ruined many farmers' livelihoods. However, new
shoots appeared in the spring and, once the dead wood was removed,
became the basis for new fruit-producing trees. In this way, an olive
tree can live for centuries or even millennia.
Olives grow very slowly, and over many years, the trunk can attain a
A. P. de Candolle
A. P. de Candolle recorded one exceeding
10 m (33 ft) in girth. The trees rarely exceed 15 m
(49 ft) in height, and are generally confined to much more
limited dimensions by frequent pruning.
Olea europaea is very hardy: drought-, disease- and fire-resistant, it
can live to a great age. Its root system is robust and capable of
regenerating the tree even if the above-ground structure is destroyed.
The older the olive tree, the broader and more gnarled the trunk
becomes. Many olive trees in the groves around the
said to be hundreds of years old, while an age of 2,000 years is
claimed for a number of individual trees; in some cases, this has been
scientifically verified. See paragraph dealing with the topic.
The crop from old trees is sometimes enormous, but they seldom bear
well two years in succession, and in many cases, a large harvest
occurs every sixth or seventh season.
Where the olive is carefully cultivated, as in
Languedoc and Provence,
the trees are regularly pruned. The pruning preserves the
flower-bearing shoots of the preceding year, while keeping the tree
low enough to allow the easy gathering of the fruit.
The spaces between the trees are regularly fertilized.
Pests, diseases, and weather
Various pathologies can affect olives. The most serious pest is the
olive fruit fly (Dacus oleae or Bactrocera oleae) which lays its eggs
in the olive most commonly just before it becomes ripe in the autumn.
The region surrounding the puncture rots, becomes brown, and takes a
bitter taste, making the olive unfit for eating or for oil. For
controlling the pest, the practice has been to spray with insecticides
(organophosphates, e.g. dimethoate). Classic organic methods have now
been applied such as trapping, applying the bacterium Bacillus
thuringiensis, and spraying with kaolin. Such methods are obligatory
for organic olives.
A fungus, Cycloconium oleaginum, can infect the trees for several
successive seasons, causing great damage to plantations. A species of
Pseudomonas savastanoi pv. oleae, induces tumour growth
in the shoots. Certain lepidopterous caterpillars feed on the leaves
A pest which spreads through olive trees is the black scale bug, a
small black scale insect that resembles a small black spot. They
attach themselves firmly to olive trees and reduce the quality of the
fruit; their main predators are wasps. The curculio beetle eats the
edges of leaves, leaving sawtooth damage.
Rabbits eat the bark of olive trees and can do considerable damage,
especially to young trees. If the bark is removed around the entire
circumference of a tree, it is likely to die. Voles and mice also do
damage by eating the roots of olives.
At the northern edge of their cultivation zone, for instance in
France and north-central Italy, olive trees suffer
occasionally from frost. Gales and long-continued rains during the
gathering season also cause damage.
As an invasive species
Olives as invasive weeds, Adelaide Hills, Australia
Since its first domestication, O. europaea has been spreading back to
the wild from planted groves. Its original wild populations in
southern Europe have been largely swamped by feral plants.
In some other parts of the world where it has been introduced, most
notably South Australia, the olive has become a major woody weed that
displaces native vegetation. In South Australia, its seeds are spread
by the introduced red fox and by many bird species, including the
European starling and the native emu, into woodlands, where they
germinate and eventually form a dense canopy that prevents
regeneration of native trees. As the climate of South
very dry and bushfire prone, the oil-rich feral olive tree
substantially increases the fire hazard of native sclerophyll
Harvest and processing
Forecasting olive crop production based on aerobiological method
Olives are harvested in the autumn and winter. More specifically in
the Northern Hemisphere, green olives are picked from the end of
September to about the middle of November. Blond olives are picked
from the middle of October to the end of November, and black olives
are collected from the middle of November to the end of January or
early February. In southern Europe, harvesting is done for several
weeks in winter, but the time varies in each country, and with the
season and the cultivar.
Most olives today are harvested by shaking the boughs or the whole
tree. Using olives found lying on the ground can result in poor
quality oil, due to damage. Another method involves standing on a
ladder and "milking" the olives into a sack tied around the
harvester's waist. This method produces high quality oil. A third
method uses a device called an oli-net that wraps around the tree
trunk and opens to form an umbrella-like catcher from which workers
collect the fruit. Another method uses an electric tool, the oliviera,
that has large tongs that spin around quickly, removing fruit from the
tree. Olives harvested by this method are used for oil.
Table olive varieties are more difficult to harvest, as workers must
take care not to damage the fruit; baskets that hang around the
worker's neck are used. In some places in Italy, Croatia, and Greece,
olives are harvested by hand because the terrain is too mountainous
for machines. As a result, the fruit is not bruised, which leads to a
superior finished product. The method also involves sawing off
branches, which is healthy for future production.
The amount of oil contained in the fruit differs greatly by cultivar;
the pericarp is usually 60–70% oil. Typical yields are
1.5–2.2 kg (3.3–4.9 lb) of oil per tree per year.
Olives are one of the most extensively cultivated fruit crops in the
world. In 2011, about 9.6 million hectares were planted with
olive trees, which is more than twice the amount of land devoted to
apples, bananas, or mangoes. Only coconut trees and oil palms command
more space. Cultivation area tripled from 2,600,000 to 7,950,000
hectares (6,400,000 to 19,600,000 acres) between 1960 and 1998 and
reached a 10-million-ha peak in 2008. The 10 largest producing
countries, according to the Food and Agriculture Organization, are all
located in the
Mediterranean region and produce 95% of the world's
Main countries of production (Year 2016 per FAOSTAT)
(in 1000s tonnes)
(in 1000s hectares)
Marinated green olives
Nutritional value per 100 g (3.5 oz)
609 kJ (146 kcal)
Vitamin A equiv.
Full Link to USDA Database entry
μg = micrograms • mg = milligrams
IU = International units
Percentages are roughly approximated using US recommendations for
Source: USDA Nutrient Database
One hundred grams of cured green olives provide 146 calories, are a
rich source of vitamin E (25% of the Daily Value, DV), and contain a
large amount of sodium (104% DV); other nutrients are insignificant.
Green olives are 75% water, 15% fat, 4% carbohydrates and 1% protein
The polyphenol composition of olive fruits varies during fruit
ripening and during processing by fermentation when olives are
immersed whole in brine or crushed to produce oil. In raw fruit,
total polyphenol contents, as measured by the Folin method, are
117 mg/100 g in black olives and 161 mg/100 g in green
olives, compared to 55 and 21 mg/100 g for extra virgin and
virgin olive oil, respectively.
Olive fruit contains several
types of polyphenols, mainly tyrosols, phenolic acids, flavonols and
flavones, and for black olives, anthocyanins. The main bitter flavor
of olives before curing results from oleuropein and its aglycone which
total in content, respectively, 72 and 82 mg/100 g in black
olives, and 56 and 59 mg/100 g in green olives.
During the crushing, kneading and extraction of olive fruit to obtain
olive oil, oleuropein, demethyloleuropein and ligstroside are
hydrolyzed by endogenous beta-glucosidases to form aldehydic
aglycones. The aglycones become soluble in the oil phase, whereas the
glycosides remain in the water phase.
Polyphenol content also varies with olive cultivar (Spanish Manzanillo
highest) and the manner of presentation, with plain olives having
higher contents than those that are pitted or stuffed.
Olive tree pollen is extremely allergenic, with an OPALS allergy scale
rating of 10 out of 10.
Olea europaea is primarily
wind-pollinated, and their light, buoyant pollen is a strong
trigger for asthma. One popular variety, "Swan Hill", is widely
sold as an "allergy-free" olive tree; however, this variety does bloom
and produce allergenic pollen.
Olive tree trunk
Olivo della Linza. 15th century
A young olive plant, germinated from a seed
Cailletier cultivar, with an olive harvest net on the ground, Contes,
Olive trees on Shōdo Island, Japan
^ "Kew World Checklist of Selected
Royal Botanic Gardens, Kew. Retrieved December 5, 2014.
Olea europaea (map)". Biota of North America Program. Retrieved
December 5, 2014.
Olea sylvestris Mill. — The
^ oliva, oleum. Charlton T. Lewis and Charles Short. A Latin
Dictionary on Perseus Project.
^ ἐλαία, ἔλαιον. Liddell, Henry George; Scott, Robert; A
Greek–English Lexicon at the Perseus Project
^ OLD s.v. oliva, Ernout & Meillet s.v. oleum.
^ "Mycenaean (Linear b) – English Glossary" (PDF).
Linear B word e-ra-wa". "The
Linear B word e-ra-wo".
Palaeolexicon. Word study tool of ancient languages.
"e-ra3-wo". Raymoure, K.A. "e-ra-wo". Minoan Linear A &
Mycenaean Linear B. Deaditerranean.
^ Eddo Rugini; Luciana Baldoni; Rosario Muleo; Luca Sebastiani (2016).
Tree Genome. Springer. p. 14.
^ Apostolos Kiritsakis and Fereidoon Shahidi (2017). Olives and Olive
Oil as Functional Foods: Bioactivity, Chemistry and Processing. John
Wiley & Sons. p. 129. ISBN 978-1-119-13531-9. CS1
maint: Uses authors parameter (link)
^ Richard Blatchly, Zeynep Delen, and Patricia O'Hara (2017). The
Chemical Story of
Olive Oil: From Grove to Table. Royal Society of
Chemistry. p. 82. ISBN 978-1-78801-230-0. CS1 maint:
Uses authors parameter (link)
^ Jozef M. Pacyna and Elisabeth G. Pacyna (2016). Environmental
Determinants of Human Health. Springer. p. 107.
^ Susan Featherstone (2015). A Complete Course in Canning and Related
Processes: Volume 3 Processing Procedures for Canned Food Products.
Woodhead Publishing. p. 113. ISBN 978-0-85709-687-6.
^ Green PS (2002). "A revision of
Olea L. (Oleaceae)". Kew Bulletin.
57 (1): 91–140. doi:10.2307/4110824. JSTOR 4110824.
^ Besnard G, Rubio de Casas R, Christin PA, Vargas P (2009).
Olea (Oleaceae) based on plastid and nuclear
ribosomal DNA sequences: Tertiary climatic shifts and lineage
differentiation times". Annals of Botany. 104 (1): 143–60.
doi:10.1093/aob/mcp105. PMC 2706730 . PMID 19465750.
^ Besnard G, Garcia-Verdugo C, Rubio de Casas R, Treier UA, Galland N,
Vargas P (2008). "Polyploidy in the
Olive Complex (
Evidence from Flow Cytometry and Nuclear Microsatellite Analyses".
Annals of Botany. 101 (1): 25–30. doi:10.1093/aob/mcm275.
PMC 2701839 . PMID 18024415.
^ a b c World
Olive Encyclopedia, International
Olive Council, 1996,
^ Lanza, Fabrizia (15 March 2012). Olive: A Global History. Reaktion
Books. pp. 106–110. ISBN 978-1-86189-972-9.
^ a b c d e Garrido Fernandez, A.; Fernandez-Diez, M.J.; Adams, M.R.
(31 July 1997). Table Olives: Production and Processing. Springer.
pp. 23–45. ISBN 978-0-412-71810-6.
^ a b Boskou, D., ed. (1996).
Olive Oil. Chemistry and Technology.
^ Therios, Ioannis Nikolaos (2009). Olives: Volume 18 of Crop
Production Science in Horticulture (History of
Olive Growing, page 1).
CABI. ISBN 978-1-84593-620-4.
^ Di Giovacchino, Luciano (2013). "3". Handbook of
Olive Oil: Analysis
& Properties (2nd ed.). Springer Science & Business Media New
York. p. 57.
^ Vossen, Paul (2007). "
Olive Oil: History, Production, and
Characteristics of the World's Classic Oils". HortScience. 42 (5):
^ Lanza, Fabrizia (2011). Olive: a global history. London: Reaktion
Books. p. 15. ISBN 978-1-86189-972-9.
^ Friedrich W.L. (1978)
Fossil plants from Weichselian interstadials,
Santorini (Greece) II, published in the "
Thera and the Aegean World
II", London, pp. 109–128. Retrieved on 2011-12-07.
Mediterranean Museums of Olive". www.oliveoilmuseums.gr. Retrieved
^ Gooch, Ellen (2005). "10+1 Things you may not know about olive oil".
Epikouria Magazine (Fall/Spring). Retrieved December 5, 2014.
^ Crosby, Alfred W. (2003). The Columbian Exchange: Biological and
Cultural Consequencies of 1492. Santa Barbara, CA: Praeger.
p. 73. ISBN 978-0-27598-092-4.
^ Carter, Nancy Carol (2008). "San Diego Olives: Origins of a
California Industry" (PDF). The Journal of San Diego History. 54 (3):
^ "Shodoshima Town". shodoshima.lg.jp.
Olive Growing and Nursery Production". International
Retrieved December 5, 2014.
^ Macdonald, Nathan (2008) What Did the Ancient
William B. Eerdmans. pp. 23–24. ISBN 978-0-8028-6298-3.
^ Cooper, John (1993). Eat and Be Satisfied: A Social History of
Jewish Food. New Jersey: Jason Aronson Inc. pp. 4–9.
ISBN 0-87668-316-2. . See also both the Hebrew and English
text in: Deut 8:8
^ Homer, Odyssey, book 5".
^ "He learned from the Nymphai how to curdle milk, to make bee-hives,
and to cultivate olive-trees, and was the first to instruct men in
these matters." (Diodorus Siculus, 4. 81. 1).
^ Toward the end of the 2nd century AD, the traveler Pausanias saw
many such archaic cult figures.
^ "Indeed it is said that at that [ancient] time there were no olives
anywhere save at Athens." (Herodotus, 5. 82. 1 ).
^ Theophrastus, On the Causes of Plants,, 4.13.5., noted by Isager,
Signe and Skydsgaard, Jens Erik (1992) Ancient Greek Agriculture, An
introduction. Routledge. p. 38. ISBN 0415001641.
^ "...which is still shown in the Pandroseion" (pseudo-Apollodorus,
^ Pausanias, Description of
Greece 1. 27. 1.
^ Isager, Signe and Skydsgaard, Jens Erik (1992) Ancient Greek
Agriculture, An introduction. Routledge. p. 35. ISBN 0415001641
^ Hort, Sir Arthur (1916).
Theophrastus Enquiry into Plants. William
Heinemann. p. 107.
^ "Ficus Ruminalis". uchicago.edu.
^ "Me pascunt olivae, me cichorea levesque malvae." Horace, Odes
1.31.15, c. 30 BC
^ Letter from
Lord Monboddo to John Hope, 29 April 1779; reprinted by
William Knight 1900 ISBN 1-85506-207-0
Vitruvius (1914) The Ten Books on Architecture. Harvard
University Press, Book1, Ch.V, Sec. 3, p. 22
^ Balfour, John Hutton (1885) "Plants of the Bible". T. Nelson and
^ Hassouna, Viktoria (2010). Virgin
Olive Oil. Books on Demand.
p. 23. ISBN 3839175054.
Leaf Burning". cyprus44.com.
Brijuni National Park. Retrieved 27 May
^ a b Vasilopoulos, Costas (17 January 2013). "Plato's Sacred Olive
Olive Oil Times. Retrieved 14 October 2017.
^ Koutoudis, Dennis. "The
Pelion Estates". Retrieved 2012-11-10.
^ a b Oliver Rackham; Jennifer Alice Moody (1996). The making of the
Cretan landscape. Manchester University Press.
ISBN 978-0-7190-3647-7. cited in F. R. Riley (2002). "Olive
Oil Production on
Bronze Age Crete: Nutritional properties, Processing
methods, and Storage life of Minoan olive oil". Oxford Journal of
Archaeology. 21: 63. doi:10.1111/1468-0092.00149.
Crete Lore". CreteWest.com. Retrieved 14 October 2017.
^ ARA, June 18, 2015. ARA-diari (2015-06-18). Retrieved on 2015-06-20.
^ Diocese of Nardò–Gallipoli. GCatholic.org
^ Al-BAB (August 2011). "Ancient
^ Drinkwater, Carol (2006). The
Olive Route. Weidenfeld &
Nicholson. ISBN 0-297-84789-9.
^ a b Kislew, M.; Tabak, Y. and Simhoni, O. Identifying the Names of
Fruits in Ancient Rabbinic Literature, Leshonenu (Hebrew), vol. 69, p.
^ Lewington, A., & Parker, E. (1999) Ancient Trees., pp 110–113,
London: Collins & Brown Ltd. ISBN 1-85585-704-9
^ Reuters (October 20, 2012). "
Jerusalem olive trees among oldest in
^ Petruccelli, R; Giordano, C; Salvatici, M. C.; Capozzoli, L;
Ciaccheri, L; Pazzini, M; Lain, O; Testolin, R; Cimato, A (2014).
"Observation of eight ancient olive trees (
Olea europaea L.) growing
in the Garden of Gethsemane". Comptes Rendus Biologies. 337 (5):
311–7. doi:10.1016/j.crvi.2014.03.002. PMID 24841957.
^ Bernabei, Mauro (2015). "The age of the olive trees in the Garden of
Gethsemane". Journal of Archaeological Science. 53: 43.
^ Babcox, Wendy (2014). "Every
Tree in the Garden of
Gethsemane". Departures in Critical Qualitative Research. 3 (2): 111.
^ "2,000-year-old Trees still producing olives". The Malta
Independent. Retrieved 14 May 2016.
^ "Race to save endemic olive tree intensifies". The Times of Malta.
Retrieved 10 August 2016.
^ "List of Historical Trees Having an Antiquarian Importance".
Government of Malta. Retrieved 14 May 2016.
^ "List of Historical Trees Having an Antiquarian Importance". UNESCO.
Retrieved 14 May 2016.
^ "Rural Development Programme for Malta 2007–2013" (PDF). Ministry
for Resources and Rural Affairs. 2009. Retrieved 10 May 2016.
^ "Trees and Woodlands Protection Regulations, 2011" (PDF). The
Government of Malta Gazette. 2011. Retrieved 10 May 2016.
^ Renfrew, Colin (1972). The Emergence of Civilization; The Cyclades
and the Aegean in the Third Millennium B.C. Taylor & Francis.
^ Essid, Mohamed Yassine (2012). Chapter 2. History of Mediterranean
Food. MediTerra: The
Mediterranean Diet for Sustainable Regional
Development. Presses de Sciences Po. p. 29.
^ a b "About Olives". International
Olive Council. Retrieved December
^ a b c Omar, S. H. (2010). "
Oleuropein in olive and its
pharmacological effects". Scientia Pharmaceutica. 78 (2): 133–54.
doi:10.3797/scipharm.0912-18. PMC 3002804 .
^ a b "Unusual Olives", Epikouria Magazine, Spring/Summer 2006
^ "Throubes". Olives South Africa. Retrieved 2017-03-22.
^ "Eat Like a Man". Esquire. Retrieved 22 September 2011.
^ Yada, Sylvia; Harris, Linda. "Olives: Safe Methods for Home
Pickling" (PDF). University of California, Division of Agricultural
and Natural Resources. Retrieved December 6, 2014.
^ a b c d Kailis, Stanley G., and David John Harris (2007). Producing
table olives. Landlinks Press.
^ Bautista-Gallego, J.; Arroyo-López, F.N.; Rantsiou, K.;
Jiménez-Díaz, R.; Garrido-Fernández, A.; Cocolin, L. (2013).
"Screening of lactic acid bacteria isolated from fermented table
olives with probiotic potential" (PDF). Food Research International.
50: 135. doi:10.1016/j.foodres.2012.10.004.
^ Silva, T.; Reto, M.; Sol, M.; Peito, A.; Peres, C.M.; Peres, C.;
Malcata, F. Xavier (2011). "Characterization of yeasts from Portuguese
brined olives, with a focus on their potentially probiotic behavior".
LWT - Food Science and Technology. 44 (6): 1349.
^ Botta, C; Cocolin, L (2012). "Microbial dynamics and biodiversity in
table olive fermentation: Culture-dependent and -independent
approaches". Frontiers in Microbiology. 3: 245.
doi:10.3389/fmicb.2012.00245. PMC 3390769 .
^ University of Catania PhD in Food Science and Technology, Food
Microbiology: "Isolation and characterization of yeasts isolated from
naturally fermented olives with brine bioprotective function"
Laboratory of Food Microbiology, DISPA, Agrarian Faculty.
^ "Oil-Cured Olives: A Kalamata Substitute?". Cooks Illustrated. May
2016. Retrieved 27 November 2016.
^ EDIBLE TREES. AnVi OpenSource Knowledge Trust. 1969.
^ Oteros, Jose (2014) Modelización del ciclo fenológico reproductor
del olivo. PhD Thesis. University of Córdoba (Spain)
^ Enciclopedia Universal Europeo Americana. Volume 15. Madrid. 1981.
Espasa-Calpe S.A. ISBN 84-239-4500-6 (Complete Encyclopedia) and
ISBN 84-239-4515-4 (Volume 15 )
^ Cavagnaro P., J. Juárez, M Bauza & R.W. Masuelli (2001).
"Discriminación de variedades de olivo a través del uso de
caracteres morfológigos y de marcadores moleculares". Agriscienta.
18: 27–35. CS1 maint: Multiple names: authors list (link)
^ "First Welsh olive grove planted on Anglesey".
^ Oteros, J., García-Mozo, H., Vázquez, L., Mestre, A.,
Domínguez-Vilches, E., Galán, C. (2013). "Modelling olive
phenological response to weather and topography". Agriculture
Ecosystems & Environment. 179: 62–68.
doi:10.1016/j.agee.2013.07.008. CS1 maint: Multiple names:
authors list (link)
^ (Lewington and Parker, 114).
^ ''Ecosfera'', Público, May 13, 2010. Ecosfera.publico.clix.pt
(2010-05-13). Retrieved on 2011-12-07 Archived May 31, 2010, at the
^ Janse, J. D. (1982). "Pseudomonas syringae subsp. savastanoi (ex
Smith) subsp. nov., nom. rev., the bacterium causing excrescences on
Oleaceae and Nerium oleander L". Int. J. Syst. Bacteriol. 32 (2):
^ Burr, M. (1999). Australian Olives. A guide for growers and
producers of virgin oils, 4th edition. ISBN 0-9577583-0-8.
^ Lumaret, Roselyne; Ouazzani, Noureddine (2001). "Ancient wild olives
Mediterranean forests". Nature. 413 (6857): 700.
^ Spennemann, D. H. R.; Allen, L. R. (2000). "Feral olives (Olea
europaea) as future woody weeds in Australia: a review". Australian
Journal of Experimental Agriculture. 40 (6): 889–901.
^ Olives as Weeds Archived February 5, 2013, at the Wayback Machine.
Plant Control Commission of South Australia
^ Oteros, J., Orlandi, F., García-Mozo, H., Aguilera, F., Dhiab, A.
B., Bonofiglio, T., ... & Galán, C. (2014). Better prediction of
Mediterranean olive production using pollen-based models. Agronomy for
sustainable development, 34(3), 685–694 
^ "Methods for harvesting olive fruit". olivemuseum.com. Retrieved 2
^ "FAO, 2004". Apps3.fao.org. Retrieved 2009-05-18.
^ Faostat.fao.org (2012-02-23). Retrieved on 2012-07-08
^ a b c "Olives and olive oil". Phenol-Explorer. Retrieved December 5,
^ Romero C, Brenes M, Yousfi K, García P, García A, Garrido A
(2004). "Effect of cultivar and processing method on the contents of
polyphenols in table olives". J Agric Food Chem. 52 (3): 479–84.
doi:10.1021/jf030525l. PMID 14759136. CS1 maint: Uses
authors parameter (link)
^ a b c Ogren, Thomas (2015). The Allergy-Fighting Garden. Berkeley,
CA: Ten Speed Press. p. 159. ISBN 978-1-60774-491-7.
^ Polito, V. "Pollination and
Fruit Set" (PDF). Retrieved 12 May
Look up olive in Wiktionary, the free dictionary.
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USDA Plants Profile for
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Olive trees (
Olea europaea) — U.C. Photo gallery
Olives at Curlie (based on DMOZ)
"Olive". Encyclopedia Americana. 1920.
Olea europaea ssp. europaea (
Olive Scientific Information)
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