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The origin of the olive tree is lost in time, coinciding and mingling with the expansion of the Mediterranean civilisations which for centuries governed the destiny of mankind and left their imprint on Western culture

Olive leaf fossils have been found in Pliocene deposits at Mongardino in Italy. Fossilised remains have been discovered in strata from the Upper Paleolithic at the Relilai snail hatchery in North Africa, and pieces of wild olive trees and stones have been uncovered in excavations of the Chalcolithic period and the Bronze Age in Spain. The existence of the olive tree therefore dates back to the twelfth millennium BC.

The wild olive tree originated in Asia Minor where it is extremely abundant and grows in thick forests. It appears to have spread from Syria to Greece via Anatolia (De Candolle, 1883) although other hypotheses point to lower Egypt, Nubia, Ethiopia, the Atlas Mountains or certain areas of Europe as its source area. Caruso for that reason believed it to be indigenous to the entire Mediterranean Basin and considers Asia Minor to have been the birthplace of the cultivated olive some six millennia ago. The Assyrians and Babylonians were the only ancient civilisations in the area who were not familiar with the olive tree.

Taking the area that extends from the southern Caucasus to the Iranian plateau and the Mediterranean coasts of Syria and Palestine (Acerbo) to be the original home of the olive tree, its cultivation developed considerably in these last two regions, spreading from there to the island of Cyprus and on towards Anatolia or from the island of Crete towards Egypt.

Olive and the Plant-Forward Kitchen

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Article Contents

Introduction, late neogene paleogeographical and pleistocene climatic changes have shaped the genetic diversity of oleaster populations, human-mediated spread and first uses of oleaster during the holocene, early olive domestication during pre-historic times and the reasons for its success, beyond the mediterranean and hybridizations between olive subspecies: new opportunities for crop diversification, toward the ecological genomics of olive domestication, overall conclusions: toward the improvement of sustainable olive agriculture, supplementary data, acknowledgements, literature cited.

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• On the origins and domestication of the olive: a review and perspectives
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Guillaume Besnard, Jean-Frédéric Terral, Amandine Cornille, On the origins and domestication of the olive: a review and perspectives, Annals of Botany , Volume 121, Issue 3, 16 February 2018, Pages 385–403, https://doi.org/10.1093/aob/mcx145

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Unravelling domestication processes is crucial for understanding how species respond to anthropogenic pressures, forecasting crop responses to future global changes and improving breeding programmes. Domestication processes for clonally propagated perennials differ markedly from those for seed-propagated annual crops, mostly due to long generation times, clonal propagation and recurrent admixture with local forms, leading to a limited number of generations of selection from wild ancestors. However, additional case studies are required to document this process more fully.

The olive is an iconic species in Mediterranean cultural history. Its multiple uses and omnipresence in traditional agrosystems have made this species an economic pillar and cornerstone of Mediterranean agriculture. However, major questions about the domestication history of the olive remain unanswered. New paleobotanical, archeological, historical and molecular data have recently accumulated for olive, making it timely to carry out a critical re-evaluation of the biogeography of wild olives and the history of their cultivation. We review here the chronological history of wild olives and discuss the questions that remain unanswered, or even unasked, about their domestication history in the Mediterranean Basin. We argue that more detailed ecological genomics studies of wild and cultivated olives are crucial to improve our understanding of olive domestication. Multidisciplinary research integrating genomics, metagenomics and community ecology will make it possible to decipher the evolutionary ecology of one of the most iconic domesticated fruit trees worldwide.

The olive is a relevant model for improving our knowledge of domestication processes in clonally propagated perennial crops, particularly those of the Mediterranean Basin. Future studies on the ecological and genomic shifts linked to domestication in olive and its associated community will provide insight into the phenotypic and molecular bases of crop adaptation to human uses.

The cultivated olive ( Olea europaea L. subsp. europaea var. europaea ; Box 1) is considered to be the most iconic tree of the Mediterranean Basin, with origins linked to the emergence of some of the most ancient civilizations, about six millennia ago ( Loumou and Giourga, 2003 ; Kaniewski et al. , 2012 ; Zohary et al. , 2012 ). In classical times, olive cultivation expanded to new regions and intensified around the Mediterranean Basin and beyond ( Infante-Amate et al. , 2016 ). Today, hundreds of olive varieties are grown to produce high-quality fruit for oil and for table consumption ( Bartolini et al. , 2005 ), but debate about their origins continues (e.g. Díez et al. , 2015 ; Besnard and Rubio de Casas, 2016 ). The relationships between cultivated olives and wild Mediterranean olives [ Olea europaea subsp . europaea var. sylvestris (Mill.) Leh., or the so-called oleaster; Box 1] are also unclear. The multiple uses of cultivated and wild olive trees, as sources of food, wood and cattle fodder, explain the expansion of olive groves with the spread of human civilization. The dual role of olives as both wild elements of the Mediterranean vegetation and as a cultivated crop has posed challenges to researchers trying to decipher the domestication history of this species. It also remains difficult to distinguish between feral (escaped from cultivation) and genuinely wild Mediterranean olives, even with the recently developed use of genetic and phenotypic traits to assist identification (Box 1). Such a tenuous domestication syndrome is a key issue that has affected research carried out on domestication of the olive, but also of other Mediterranean woody crops such as grape and date palm ( Zohary et al. , 2012 ). For all these reasons, there has long been speculation about the origin and domestication history of olives, mostly based on botanical data (e.g. Newberry, 1937 ; Chevalier, 1948 ; Turrill, 1951 ).

Six wild olive subspecies are currently recognized ( Fig. B1 A ) and considered to be primary genetic resources for cultivated olive breeding ( Zohary, 1994 ; Green, 2002 ). They are diploid, except for subspp. maroccana and cerasiformis , which are polyploid (6x and 4x, respectively; Besnard et al., 2008 ). In tropical and sub-tropical regions, non-Mediterranean olives (subspp. cuspidata and laperrinei ) harbour small fruits (diameter generally <8 mm; Médail et al., 2001 ) and trees usually grow in mountainous areas ( Fig. B1 B ). The African olive (subsp. cuspidata ) can also invade anthropogenic habitats, as observed in Australia ( Fig. B1 C ). The taxonomy of the olive complex is relatively well supported by genetic data (e.g. Rubio de Casas et al., 2006 ; Besnard et al., 2007 ). Each subspecies harbours specific plastid lineages/sub-lineages, with several lineages/sub-lineages detected within the four diploid subspecies. The 13 plastid lineages/sub-lineages are specified on the map ( Fig. B1 A ).

The olive complex ( Olea europaea L.). (A) Native distribution of wild olive relatives (according to Rubio de Casas et al. , 2006 ). Six subspecies are currently recognized ( Green, 2002 ). The plastid DNA data set used to define lineages (and sub-lineages) is available in Supplementary Data Table S2 and Fig. S2 . Dotted lines indicate approximate limits of the distributions of two adjacent plastid lineages (indicative for putative secondary contacts). Note that lineages E2 and E3 are admixed in western Oleaster populations (subsp. europaea ); (B–F) Various habitats with wild or cultivated olives in native and invasive ranges. (B) Ramets from the same stump of a Laperrine’s olive at Akerakar, south Algeria. Subspecies laperrinei persists in very dry habitats (mean annual rainfall <100 mm); (C) African olive invasion at Mt Annan, NSW, Australia (photo credit: Peter Cuneo). Subspecies cuspidata is highly invasive in east Australia, north New Zealand and Hawaii. It usually colonizes disturbed habitats, such as abandoned pastures in particular ( Cuneo and Leishman, 2006 ); (D) scrubland dominated by oleasters at Lageia, Cyprus; (E) Traditional agrosystem with cultivated olives in northern Morocco (Chefchaouen, Rif). Annual crops (here, wheat) are usually cultivated between trees; (F) monoculture of olive trees near Mattinata, Puglia, Italy. A small number of genotypes (usually one or two major clones) are generally cultivated in such agrosystems.

Nuclear and plastid DNA data (e.g. Angiolillo et al. , 1999 ; Besnard et al. , 2007 ) show that the main wild progenitor of the cultivated olive ( O. europaea subsp. europaea var. europaea ) is the wild Mediterranean olive, also known as the oleaster ( O. europaea subsp. europaea var. sylvestris ; Fig. B1 D ). Two main oleaster genepools have been identified in the Western and Eastern Mediterranean Basin ( Besnard et al. , 2001b , 2013b ; Breton et al. , 2006 ; Belaj et al. , 2007 , 2011 ; Díez et al. , 2015 ). Two specific plastid lineages (E2 and E3) are admixed in the Western Mediterranean Basin, and one lineage (E1) is highly diversified in the Eastern Mediterranean Basin ( Besnard et al. , 2013a ). Nuclear DNA sequences have also revealed two or three divergent lineages of alleles in oleaster, with a weaker geographic structure than for chloroplast markers ( Besnard and El Bakkali, 2014 ). This contrasting phylogeographic patterns between plastid and nuclear markers can be explained by differences in inheritance pattern (i.e. maternal for chloroplast markers and biparental for nuclear markers). However, the absence of a strong phylogeographic signal for nuclear markers probably reflects metapopulation dynamics, with recurrent breaks in gene flow and reconnections due to environmental changes ( Rubio de Casas et al. , 2006 ).

Oleaster and cultivated olive have overlapping distributions, ecological and morphological features, to the extent that the domesticated nature of olive is often questioned, as for many other perennials ( Miller and Gross, 2011 ; Gaut et al. , 2016 ; Gros-Balthazard et al. , 2016 ). Historically, olive domestication processes have involved the selection of trees propagated by vegetative means and the repeated cultivation of spontaneously growing trees with favourable agronomic traits. Such mixtures of practices have continually shaped ecological, morphological and genetic differentiation between wild and cultivated trees since pre-historic times, through a long-standing process aiming to optimize fruit production (e.g. Terral et al. , 2004a ; Newton et al. , 2014 ), and they continue to occur at various sites throughout the Mediterranean Basin. On dissection, cultivated olives and genuine oleaster fruits can be differentiated on the basis of ecological, morphological and genetic differences. Both cultivated and wild olive populations display significant genetic differentiation, despite the occurrence of numerous feral and admixed forms (escapees from cultivation), which considerably blur the pattern of genetic and phenotypic differentiation (e.g. Bronzini de Caraffa et al. , 2002 ; Breton et al. , 2006 ; Belaj et al. , 2007 , 2011 ; Hannachi et al. , 2008 ; Besnard et al., 2013a, b ; Dίez et al. , 2015 ). This genetic differentiation is less strong in olive than in other fruit trees ( Cornille et al. , 2014 ; Gaut et al. , 2015 ), possibly due to the particularly long generation time (>100 years for population turnover) of this species and recurrent cultivated–wild gene flow. Abrupt changes in the size and shape of olive stones during the Bronze Age (from round to elongate), with determinants other than environmental factors ( Terral and Mengüal, 1999 ), also provide evidence for genetic changes in the exploited germplasm. Finally, quantitative trait analyses have revealed a panel of phenotypic and genetic differences between cultivated and wild olives for agronomic traits ( Table 1 ). Furthermore, as genotypes can be maintained over long periods, somatic mutations may have also arisen (e.g. self-compatibility; Breton et al. , 2014 ), generating phenotypic and genetic variability ( Gaut et al. , 2015 ).

Main characteristics usually used to distinguish between oleaster and cultivated olive in the Mediterranean Basin

The recent accumulation of paleobotanical, archeological, historical and molecular data (e.g. Terral et al. , 2004a ; Carrión et al. , 2010 ; Kaniewski et al. , 2012 ; Besnard et al. , 2013b ; Margaritis, 2013 ; Newton et al. , 2014 ; Dίez et al. , 2015 ; Rugini et al. , 2016 ; see Supplementary Data Table S1 for current available genetic data) has made a crucial re-evaluation of the biogeography of wild olives and the history of their cultivation timely. Major issues in the domestication history of the olive remain to be resolved, and these points are dealt with in this review. Further investigations are required to elucidate the processes underlying the primary domestication and subsequent secondary diversification of olives. Besides, little is known about the selection by humans of agronomic or adaptive phenotypic traits in olive. Improving our understanding of the ecology of both wild and cultivated olives is also a critical step to deciphering their domestication history and assessing their probable future resilience to global changes ( Holliday et al. , 2017 ). Finally, a lot still needs to be learnt about the biotic and abiotic interactions of olives with their environment. The recent spread of major pathogens and pests remains also poorly explained (e.g. Verticillum , Phytophtora , olive fly; Martelli et al. , 2002 ; Nardi et al. , 2010 ). Xylella fastidiosa , a bacterium introduced from America and then disseminated by native vector insects in South-East Italian olive groves, is a prime example of the emergence of a pathogen, outbreaks of which pose a serious threat to both cultivated and wild olives ( Saponari et al. , 2014 ).

Here, we review the timeline of olive evolution in the Mediterranean Basin from its origin during the Quaternary until its domestication, diversification and selection for cultivation nowadays. In the light of new paleobotanical, archeological, historical and molecular data, we discuss the questions that remain unanswered, or even unasked, and we propose to study the ecological genomics of wild and cultivated olives to unravel the puzzle of olive domestication. In particular, we discuss perspectives of multidisciplinary researches and highlight recent technological advances in genomics, metabarcoding and ecological modelling that hold great promise for further documentation of the domestication process of the olive, as well as of other woody crops. These findings should contribute to the sustainable management of cultivated olive germplasm for future breeding programmes and for the conservation of wild olive populations, particularly in the current context of global change.

The natural distribution of wild olives ( Olea europaea ) extends from South Africa to South Asia, and encompasses the Saharan mountains, Macaronesia and Mediterranean countries ( Green, 2002 ; Box 1). Paleobotanical data attest to the occurrence of Olea sp. in Europe during the Oligocene–Miocene boundary (gypsum flora of Aix-en-Provence, South-east France; de Saporta, 1873 ). This taxon became an important component of the vegetation of the Mediterranean region during the Early Miocene ( Suc et al. , 1984 ; Palamarev, 1989 ; Terral et al. , 2004b ), and was probably an ancestor of the oleaster (Box 1). Phylogenetic analyses have suggested that the most recent common ancestor of the six olive subspecies ( Fig. 1 ) was present during the Late Miocene or Early Pliocene [about 4.0–8.3 million years ago (Mya); Besnard et al. , 2009 ]. Gene flow between North African and tropical African olive populations has long been limited, due to successive phases of aridification of the Saharan region from the Late Miocene until the present ( Schuster et al. , 2006 ; Swezey, 2009 ), although conditions in this area were more humid from 11 800 to 4900 years before the present (BP) ( Tierney et al. , 2017 ). This limitation of gene flow may explain the early divergence of subsp. cuspidata from the other subspecies ( Besnard et al. , 2009 ). The divergence of the three extant plastid lineages of oleaster (E1, E2 and E3; Box 1; Fig. 1 ; Supplementary Data Fig. S1 ) has been dated to the Late Pliocene or Early Pleistocene ( Besnard et al. , 2013b ), possibly around the time of the Messinian salinity crisis (Miocene/Pliocene). With the gradual establishment of the Mediterranean climate, thermophilic and xerophytic plant species (e.g. evergreen Quercus sp., Olea sp. and Pistacia sp.) emerged and rapidly replaced sub-tropical species ( Suc et al. , 1984 ).

Distribution of chlorotypes (A) in oleaster populations, and (B) in the Mediterranean cultivated olive [based on data from Besnard et al. (2013b) ]. Each chlorotype is represented by a specific motif, as defined in Supplementary Data Fig. S1 . The number of accessions ( n ) and the total diversity ( H T ; Nei, 1987 ) of chloroplast DNA variation are given for each area and for the total sample. The size of pie charts is proportional to the number of individuals analysed per area. Chlorotypes primarily found in oleaster were mostly observed in the East (from the Peloponnese to the Levant; lineage E1) and westernmost part of the Mediterranean Basin (Iberian Peninsula and Morocco; lineages E2 and E3). Note that the geographic distribution of chlorotypes is clearly different between wild and cultivated olives, despite the extensive admixture of these two forms. In the western Mediterranean oleaster, lineage E1 is represented by only three chlorotypes (E1- e .1, E1- e .2 and E1- e .3) that were recently introduced into this area with the human-mediated spread of Levantine cultivated olives ( Besnard et al. , 2013b ). For a detailed distribution of chlorotypes at the population level, see Besnard et al. (2013b) .

The Pleistocene (from about 2.58 Mya to 11 700 BP) was also characterized by extreme climatic events, with cold and dry periods generally less favourable to thermophilic Mediterranean species such as the olive. These environmental shifts influenced the distribution of many species and left imprints in their genomes ( Hewitt, 2004 ). The geographic distribution and genetic structure of wild olive populations are the result of a long process of recursive contraction and expansion in response to climatic shifts, and of the limited gene flow imposed by geographic distance and natural barriers, such as deserts and seas. Studies based on nuclear microsatellite markers have revealed the presence of two different oleaster genepools in the Western and Eastern Mediterranean Basin [i.e. ‘Wild East’ (WE) and ‘Wild West’ (WW), Fig. 2 ; Breton et al. , 2006 ; Besnard et al. , 2001b , 2013b ; Díez et al. , 2015 ]. In parallel, plastid markers have revealed strong differentiation between eastern and western oleaster populations ( Fig. 1A ). Before the spread of both oleaster and cultivated olives by humans, the E1 plastid lineage was probably restricted to the east, from the Levant to Greece, whereas the other two plastid lineages (E2 and E3) were specific to the western and central regions ( Besnard et al. , 2013b ). A coalescent-based Bayesian approach indicated that the three Mediterranean plastid lineages diversified long before the Last Glacial Maximum, probably during the long MIS5 interglacial period (from 130 000 to 74 000 BP; Besnard et al. , 2013b ). Nuclear and plastid DNA analyses also revealed a natural zone of contact between eastern and western wild olive populations in the Peloponnese ( Besnard et al., 2013a, b ). Similar geographic patterns of genetic differentiation and diversification have been observed for two other shrubs found around the Mediterranean [ Laurus nobilis and Myrtus communis ( Rodríguez-Sánchez et al. , 2009 ; Migliore et al. , 2012 )], suggesting that the climatic changes during the Late Pliocene and Pleistocene had similar effects on different Mediterranean species.

Bayesian inference of population structure (based on ten nuclear microsatellite loci) in the Mediterranean olive (including both cultivated and wild accessions; 860 individuals), for K = 2, 3 and 5 clusters [modified from Besnard et al. (2013a) ], inferred with a model-based clustering method implemented in STRUCTURE v.2.3.4 ( Pritchard et al. , 2000 ). Q is the membership coefficient. H’ is the similarity coefficient between ten runs for each K , and Δ K is an ad-hoc measure described by Evanno et al. (2005) . According to Δ K and H’, the most probable genetic structure model is K = 2 clusters (Δ K = 3536.7 and H’ = 0.99), with most wild accessions from the Western and Central Mediterranean Basin (cluster WW; * or E-I in the article by Besnard et al. , 2013 a ) distinguished from cultivars and eastern wild accessions (cluster WE; or E-II); at K = 3, the western oleaster cluster remains but eastern cultivated olives and oleasters are distinguished from western and central Mediterranean cultivars (cluster Q); and at K = 5, a trend for the occurrence of a cultivar cluster in each pre-defined geographic zone [i.e. West (Q1), Central (Q2) and East (Q3)] is revealed, as reported by Haouane et al. (2011) , Belaj et al. (2012) and Díez et al. (2012) . Central Mediterranean cultivars revealed the highest level of admixture among the Q1, Q2 and Q3 genepools, consistent with the inferred admixed ancestry of most of its genotypes, whereas western and eastern cultivars were found to be more strongly assigned to their respective genepools. The five genetic clusters are named as described by Díez et al. (2015) . In each group (oleaster or cultivars), the individuals are classified on the axis, from left to right, according to their geographic origin (from west to east).

Genetic markers have also facilitated the identification of hotspots of diversity in the wild olive and tracing of the origins of cultivated genotypes, through the characterization of nuclear and plastid DNA genepools, in particular (Box 1). Many plastid haplotypes (or chlorotypes) in oleaster are confined to small areas, but a few have spread across the Mediterranean Basin ( Besnard et al. , 2013b ). Three regional diversity hotspots for plastid DNA have been identified in the Levant, the Aegean region and extending from southern Spain to Morocco (Gibraltar to the Anti-Atlas). The high degree of genetic diversity in these three areas suggests that they have served as long-term refugia for the oleaster, a hypothesis supported by paleobotanical data ( Figueiral and Terral, 2002 ; Carrión et al. , 2003 ; Terral et al. , 2004b; , Willner et al. , 2009 ; Biltekin et al. , 2015 ) and species distribution modelling ( Besnard et al. , 2013b ). Barriers to dispersal (e.g. the Libyan Desert, Adriatic and Aegean Seas, and Rechinger’s Line in southern Turkey) and ecological factors (e.g. biotic interactions or abiotic factors) may also have played a crucial role in limiting long-distance dispersal, thereby maintaining strong genetic differentiation between distant geographic areas even during favourable, interglacial periods.

During the post-glacial period (about 11 700 to 8000 BP), wild olive populations recolonized the Mediterranean area from refugia, as shown by the fossil and sub-fossil records ( Figueiral and Terral, 2002 ; Terral et al. , 2004b ; Carrión et al. , 2010 ). It is thought that the expansion of olive populations was triggered by climate and then favoured by human activity, as habitats were cleared (e.g. green oak deforestation; Terral and Mengüal, 1999 ; Figueiral and Terral, 2002 ; Combourieu-Nebout et al. , 2013 ). Indeed, the abundance of olive trees in Holocene palynological records steadily increased with human activity in both the Eastern and Western Mediterranean Basin ( Carrión et al. , 2010 ). Several authors have documented the human exploitation of oleaster since the Upper Paleolithic and Early Neolithic ( Kislev et al. , 1992 ; Terral, 2000 ; Terral et al. , 2004a ; Carrión et al. , 2010 ; Kaniewski et al. , 2012 ; Zohary et al. , 2012 ). This early exploitation and further spread was probably linked to various uses, including fruit consumption, wood and cattle forage ( Renfrew, 1972 ; Terral, 2000 ; Margaritis, 2013 ). Wild olive foliage is still frequently consumed by cattle in the Cádiz province (Spain), Corsica and Morocco, where this species remains a major component of the landscape (Box 1). Olive trees also provide livestock with shade in open habitats. Oleaster was integrated into early Mediterranean agrosystems, as a cornerstone species, but its early exploitation and spread around the Mediterranean Basin and beyond [e.g. Tassili n’Ajjer ( Besnard et al. , 2013a )] was considered by Renfrew (1972) and Margaritis (2013) to be a pre-domestication step. Indeed, the practice of pruning oleasters may have greatly favoured flowering and thus fruit production, a critical step for olive domestication, even before the selection and propagation of selected clones for their agronomic value.

Olive domestication is characterized by vegetative propagation of the most valuable genotypes ( Zohary et al. , 2012 ), selected for their agronomic value (such as higher fruit set, larger fruits and higher oil content), for their ability to grow in anthropogenic environments and the ease with which they could be vegetatively propagated through cuttings or grafting. Olive cutting is relatively easy, but not the best way to propagate this species, because cuttings of cultivated varieties may have undesirable features (e.g. high sensitivity to soil pathogens). Grafting is considered to be a major innovation in the history of temperate and Mediterranean fruits and probably favoured the spread of these crops from the Middle East and Central Asia to Western Europe ( Juniper and Maberly, 2006 ). The grafting of cultivated olive varieties onto local oleaster or ancient cultivars is a widespread practice ( Díez et al. , 2011 ; Barazani et al. , 2014 ; Aumeeruddy-Thomas et al. , 2017 ). Evidence of olive grafting is missing from the archeological record, but this practice is documented in texts and epigraphic data ( Mudge et al. , 2009 ). Olive grafting has been reported since Classical times, particularly in Ancient Greece and Ancient Rome, and is designed to provide productive varieties with more hardy roots (in Pease, 1933 ). In contrast to other fruit crops, such as grape or apple ( Myles et al. , 2011 ; Cornille et al. , 2014 ; Warschefsky et al. , 2016 ), the intentional breeding of rootstocks is poorly documented in olive ( Barazani et al., 2014 , 2017 ). Barazani et al. (2017) recently showed that scion/rootstock genotype combinations are not randomly distributed, suggesting that growers may have selected some combinations in the Levant area, possibly to improve oil quality or drought tolerance.

Elucidating ancient cultural shifts linked to the beginning of cultivated olive use and breeding is not a straightforward task (e.g. Galili et al. , 1997 ; Terral et al. , 2004a ; Kaniewski et al. , 2012 ; Zohary et al. , 2012 ; Newton et al. , 2014 ). Indeed, the multiple uses of olive trees have made it difficult to interpret archeological and sub-fossil data (i.e. pollen and charcoal abundance; Kaniewski et al. , 2009 ). Olive domestication can be viewed as an ecological and historical process, that can be studied within a multidisciplinary framework, through the use of archeological, archeobotanical, historical and genetic approaches.

The archeological and archeobotanical evidence

Major human civilizations emerged in the Middle East during the Neolithic, and archeological remains have demonstrated the involvement of these civilizations in an olive oil trade during the Chalcolithic period (6000–5500 BP; Galili et al. , 1997 ; Kaniewski et al. , 2012 ; Zohary et al. , 2012 ; Newton et al. , 2014 ). Olive domestication is generally thought to have begun after this period ( Liphschitz et al. , 1991 ; Galili et al. , 1997 ). Several studies have shown that olive cultivation was a regionally and temporally diverse process, possibly due to climatic fluctuations (e.g. Kaniewski et al. , 2012 ; Langgut et al. , 2016 ; Dighton et al. , 2017 ). Olive domestication probably occurred in a diffuse manner in the Levant, making it difficult to track early origins based on archeobotanical data alone. In areas far outside the natural range of the oleaster, numerous finds of charred wood and stones associated with dates, pulses and cereals have provided indirect proof of technological developments in agronomy, such as seedling transplantation and crop irrigation ( Neef, 1990 ; Newton et al. , 2006 ; Zohary et al. , 2012 ). Kislev et al. (1995) used traditional morphological stone characters to describe numerous Chalcolithic olive remains (dating from about 5600 BP) from a submerged site off the Carmel coast in Israel. Their findings provide evidence supporting the earlier existence of cultivation in localized regions. Kislev et al. (1995) showed that oleasters growing near the site were harvested by inhabitants, and concluded that the olive industry preceded olive domestication by several centuries.

Archeological and archeobiological records (i.e. changes in the size and shape of olive stones; Table 1 ) have also provided evidence of olive exploitation and management in the Central and Western Mediterranean during the Chalcolithic/Bronze Age (4500–4000 BP), an extensive process that was probably initiated during the Neolithic (e.g. Terral and Arnold-Simard, 1996 ; Terral, 2000 ; Terral et al. , 2004a , Margaritis, 2013 ; Pagnoux, 2016; D’Auria et al. , 2017 ). In the southern and eastern Iberian Peninsula, abrupt changes in the shape of charred olive stones recovered from Bronze Age settlements suggest the presence of domesticated olives two millennia before the arrival of the Phoenicians and Roman colonization, to which the introduction of new varieties into the region and the development of olive farming, respectively, are generally attributed ( Brun, 2003 , 2004 ; Terral et al. , 2004a ). A concomitant sudden increase in the numbers of olive stone remains was detected at Eastern and Western Mediterranean archeological sites, corresponding to the Late Bronze Age (about 3500–3000 BP; Terral et al. , 2004a ; Newton et al. , 2014 ), but morphotypes typical of the Middle East did not appear in the western archeological record until 1000–1500 years later ( Newton et al. , 2014 ), attesting to the fundamental role played by East–West human migrations (e.g. ( Chikhi et al. , 2002 ) in the constitution of olive agrobiodiversity in the Western Mediterranean Basin.

The genetic evidence

The genome of current olive varieties bears witness to the origin of cultivated olives largely from oleaster populations in the Eastern Mediterranean region, consistent with a primary origin in the Middle East (e.g. Besnard et al. , 2001b , 2013a ; Lumaret et al. , 2004 ; Baldoni et al. , 2006 ; Breton et al. , 2006 ; Dίez et al. , 2015 ). Three chlorotypes, common to wild olives and belonging to lineage E1 (i.e. E1- e .1, E1- e .2 and E1- e .3), characterize about 90 % of cultivars ( Fig. 1 ; Supplementary Data S1 ). These chlorotypes are now observed in feral olives throughout the Mediterranean Basin. The chlorotypes of the remaining 10 % of cultivars belong to the E2 and E3 lineages (i.e. E2.1, E2.2, E3.1 and E3.2). Based on the current distribution of E1 diversity in oleasters, the main cultivated olive chlorotypes (i.e. E1- e .1, E1- e .2 and E1- e .3) are thought to have originated along the current border between north-west Syria and south-east Turkey, close to an area inferred to be suitable for the long-term persistence of olive trees during the Late Pleistocene ( Besnard et al. , 2013b ). In contrast, a recent study suggested that wild olives may have persisted over long time periods on the Mount Carmel Coast (north-west Israel), where early cultivation has been reported ( Kislev et al. , 1992 ), and trees from this area may have contributed to the cultivated olive genepool ( Barazani et al. , 2016 ). However, several genetic studies have shown that the oleaster populations of the Mount Carmel area are mostly feral (e.g. Besnard et al. , 2001b ; Lumaret et al. , 2004 ; Díez et al. , 2015 ). The presence of long-standing populations should be also supported by endemic chloroplast haplotypes, but chloroplast profiling has revealed the presence of the main cultivated haplotype only (E1- e .1; Besnard et al. , 2013b ), suggesting that these local wild forms probably escaped from cultivation.

Nuclear markers have also confirmed the strong eastern affiliation of the cultivated genepool, although a significant contribution of western oleasters has also been demonstrated in the Central and West Mediterranean Basin ( Besnard et al. , 2001b , 2013a ; Lumaret et al. , 2004 ; Breton et al. , 2006 ; Díez et al. , 2015 ). In addition, studies of the nuclear genetic diversity of cultivated olive have revealed a weak genetic structure in the Mediterranean Basin, mostly explained by geographic origin and different uses (i.e. oil or as whole fruits) of varieties (e.g. Claros et al. , 2000 ; Belaj et al. , 2001 ; Besnard et al. , 2001a ; Hagidimitriou et al. , 2005 ; Owen et al. , 2005 ; Marra et al. , 2013 ; Linos et al. , 2014 ; Yoruk and Taskin, 2014 ; Biton et al. , 2015 ). These data, therefore, support multiple geographic origins of cultivars, but reflect a process of diversification in the Central and West Mediterranean Basin ( Besnard et al. , 2001b , 2013a ; Díez et al. , 2015 ). However, these studies based on nuclear markers are not entirely satisfactory, because they were based on limited oleaster samples or small numbers of loci. Additional analyses will be required to refine the domestication and diversification scenario for cultivated olives (Box 2). Additional sampling of genuinely wild olives will also be required to determine whether there were diffuse origins of domesticated olives in the Middle East (e.g. Barazani et al. , 2016 ; Langgut et al. , 2016 ; Dighton et al. , 2017 ).

Finally, the local selection of cultivars by farmers may have played a key role during the recent diversification history of the cultivated olive, as described for other woody crops, such as grapes ( Bowers et al. , 1999 ; Myles et al. , 2011 ; Bacilieri et al. , 2013 ). Parentage analyses on cultivated genotypes from the same area (e.g. Marra et al. , 2013 ; Dίez et al. , 2015 ) revealed a narrow genetic basis of the current elite olive material in the West Mediterranean Basin. In particular, Dίez et al. (2015) used a large number of cultivars to demonstrate that most south Iberian varieties (group Q1) have a recent origin following a strong bottleneck (possibly during the Al-Andalus period; about 711 to 1492 AD). Using co-ancestry analyses, they identified two ancient genotypes that may have been the main progenitors of Q1. Thus, selection of the Q1 cultivar group (which includes some of the most important varieties worldwide, such as ‘Picual’, ‘Cornicabra’, ‘Hojiblanca’, ‘Manzanilla de Sevilla’ and ‘Picholine Marocaine’) was initially based on a very small number of genotypes.

New and older lines of evidence clearly indicate the existence of multiple centres of diversity for cultivated olive trees. The characterization with nuclear microsatellites of comprehensive samplings of modern olive cultivars by independent research teams revealed the existence of three main cultivated genepools ( Figs B2 A , B ) corresponding to three geographic areas: the west, centre and east Mediterranean Basin (i.e. Q1, Q2 and Q3, respectively, according to Dίez et al. , 2012 , 2015 ; see also Haouane et al. , 2011 ; Belaj et al. , 2012 ; Besnard et al. , 2013a ). Other studies have reported regional structure, probably due to the selection of very closely related individuals locally (e.g. Khadari et al. , 2003 ; Breton et al. , 2006 ; Albertini et al. , 2011 ; Muzzalupo et al. 2014 ). It remains unclear whether the centres of diversity result from one or multiple local domestication events. Dίez et al. (2015) stressed the relatively close association between the Q2 group and the WW wild genepool, with much greater plastid variation in Q2 than in Q1 and Q3 ( Fig. B2 C ). The Q2 group may, therefore, represent a separate domesticated lineage originating from WW that subsequently admixed with cultivated eastern germplasm (Q3). Dίez et al. (2015) favoured this hypothesis of an independent domestication of Q2 because (1) multiple maternal plastid lineages may reflect multiple domestication events; (2) admixture estimates suggest a substantial proportion of the WW group (20 %) in Q2; and (3) Q2 cultivars bear some wild-like phenotypic characteristics, such as low endocarp weight and a smooth endocarp surface ( Belaj et al. , 2011 ; Klepo et al. , 2013 ). This hypothesis remains to be explored, because cultivated olive diversification may also have occurred in the Central and Western Mediterranean Basin not as the result of local independent domestication, but as a consequence of admixture between local unselected pre-domesticated oleaster and cultivars introduced from the east ( Besnard et al. , 2001b , 2013a , b ; Lumaret et al. , 2004 ; Baldoni et al. , 2006 ; Dίez et al. , 2015 ). In accordance with this second hypothesis, Besnard et al. (2013a) showed, through nuclear microsatellite analysis, that most Mediterranean cultivars were assigned most strongly to the eastern oleaster genepool (cluster WE), whereas no cultivar was unambiguously assigned to the western genepool (WW), including those with plastid lineages originating from the Western Mediterranean Basin ( Fig. 2 ). This finding supports the hypothesis that current elite cultivars either belong to the eastern genepool or are admixed. In addition, several teams have reported a significant excess of heterozygosity in cultivated olive ( Dίez et al. , 2011 ; Besnard et al. , 2014 ), consistent with the hypothesis of admixture-mediated diversification of the crop (i.e. a single initial domestication followed by secondary domestication events). Biton et al. (2012) reported hybrid vigour in F 1 olive progeny, suggesting that admixture between genepools may generate superior new genotypes (i.e. due to heterosis), particularly for agronomic traits (e.g. fruits weight or oil content).

Alternative scenarios of independent local domestications, primary domestication followed by secondary diversification, or this second scenario plus local domestication events can be formally tested (see propositions in Fig. B2 C ), by approximate Bayesian computation (ABC), for example (see Díez et al. , 2015 ). Such investigations would require consensual sampling and genetic markers. In particular, caution is required when feral olives are considered, because these trees originate directly from cultivated olive and may be admixed with other spontaneously growing olives ( Beghé et al., 2017 ). Their direct filiation to cultivars is a strong limitation on studies aiming to assign cultivated trees to wild genepools (e.g. Breton et al. , 2006 ), and a large number of genetic markers and large samples of both cultivated and uncultivated olives will be required to distinguish feral trees (escapees from cultivation) from genuinely wild olives. Admixed populations should also be avoided to exclude recent gene flow between cultivated and wild olives.

Debate about olive evolutionary history and domestication. (A and B) Distribution of wild and cultivated genepools in the Mediterranean Basin ( Besnard et al. , 2013a ; Dίez et al. , 2015 ). (A) WW and WE (E-I and E-II, respectively, in the article by Besnard et al. , 2013a ) correspond to the western and eastern Mediterranean oleaster populations that expanded extensively during the Holocene, with habitat clearance mediated by humans. Contact is thought to occur in the Central Mediterranean area (e.g. Peloponnese; Besnard et al. , 2013a ). (B) Q1, Q2 and Q3 correspond to the main genetic clusters of cultivated olive ( Fig. 2 ; named according to Dίez et al. , 2015 ). (C) Simplified scenarios of domestication. Two alternative scenarios of population divergence and admixture are proposed, but there are many other non-exclusive possibilities. In both cases, the divergence of eastern and western oleaster genepools is thought to have started during the Late Pliocene (i.e. based on molecular dating; Besnard et al., 2009 , 2013b ), with possible gene flow (as indicated by arrows). Population reduction followed by subsequent expansion is also thought to have occurred during the Last Glacial Maximum and the Holocene. On the left, a primary domestication event (red circle) is thought to have occurred in the Eastern Mediterranean Basin, leading to Q3, whereas Q2 and Q1 were derived from admixture events (horizontal connections) between Q3 and WW (for Q2) or Q3 and Q2 (for Q1). For Q1, the red question mark indicates a possible alternative admixture event involving local wild genepools (i.e. WW instead of Q2; see Dίez et al. , 2015 ). A bottleneck is also indicated for Q1, as revealed by Dίez et al. (2015) . On the right, two independent primary domestication events are considered, one for Q3 in the Eastern Mediterranean Basin, and one for Q2 in the Central Mediterranean Basin. As Q2 cultivars include a high proportion of E1 haplotypes (see Dίez et al. , 2015 ), and a relatively strong genetic affinity with WE on the basis of nuclear loci ( Fig. 2 ; Besnard et al. , 2013a ; Dίez et al. , 2015 ), we presume that admixture between WE and WW occurred before domestication, but it would be difficult to distinguish between this scenario and early domestication from WW, followed by introgression from Q3, as suggested by Dίez et al. (2015) . The origin of Q1 is identical in both scenarios. Note that feral olives are not shown here, but could be considered as additional populations. Indeed, numerous intermediate forms have probably escaped from cultivation and may have contributed to the diversification of cultivated olives.

Wild diploid olive subspecies are cross-compatible and can be considered as primary genetic resources for improving the cultivated olive genepool (e.g. Zohary, 1994 ; Besnard et al. , 2008 ; Hannachi et al. , 2009 ; Klepo et al. , 2013 ; Cáceres et al. , 2015 ), although some genomic incompatibilities may exist. As described above, wild olives are naturally distributed over three continents and grow in contrasting environments (Box 1; Médail et al. , 2001 ; Green, 2002 ). They have a considerable potential for crop improvement. The introgression of diversity from wild species into cultivated olive might facilitate the introduction of various adaptive traits, such as pathogen and pest resistance and/or lead to the production of vigorous rootstocks resistant to extreme abiotic conditions (e.g. Lavee and Zohary, 2011 ; Warschefsky et al. , 2014 ; Arias-Calderón et al. , 2015 ; Trapero et al. , 2015 ). Non-natural contacts between the cultivated olive and non-Mediterranean wild relatives have been mediated by humans through the diffusion of cultivars, and gene flow between different olive subspecies has occurred in both the native and introduced ranges of O. europaea ( Besnard et al. , 2013a , 2014 ).

Within its native range, the cultivated olive historically spread beyond the boundaries of the Mediterranean Basin, further into the Middle and Far East (from Iraq to south-wesr China), but also into numerous oases (e.g. Palmyra, Syria; Kharga, Egypt; Ziz Valley, Morocco; Kufra, Libya; and Erkowit, north-east Sudan), the Canary Islands and, possibly, the mountains of the Sahara ( Besnard et al. , 2013a ; Noormohammadi et al. , 2014 ; Mousavi et al., 2014 , 2017 ; Hosseini-Mazinani et al. , 2014 ; Zhan et al. , 2015 ; Djamali et al. , 2016 ). During these various introduction events, cultivated olives may have come into contact with the wild subspecies cuspidata (e.g. China, Iran, Arabia and north-east Sudan), guanchica (Canary Islands) or laperrinei (Saharan Mountains). Crop diversification through admixture with close relatives has been documented in other fruits trees over their worldwide range, particularly for grapes ( Myles et al. , 2011 ), apples ( Cornille et al. , 2012 ), almonds ( Delplancke et al. , 2013 ) and date palms ( Hazzouri et al. , 2015 ; Zehdi-Azouzi et al. , 2015 ). There have been few studies of such a scenario in olives, but anecdotal cases of early-generation hybrids (BC1 or BC2) between Laperrine’s olive and Mediterranean olives have been reported (e.g. the cultivar ‘Dohkar’; Besnard et al. , 2013a ).

The cultivated olive has more recently been introduced into new regions, such as the New World, New Zealand and Australia. The introduction of multiple varieties, usually from different origins, has ensured the maintenance of substantial genetic diversity in the cultivated genepool in these regions. During crop diffusion, new genotypes (putatively more adapted to local conditions) were also selected, after uncontrolled crosses occurred between cultivars and feral olives (e.g. do Val et al. , 2012 ; Mousavi et al. , 2014 ; Beghé et al. , 2015 ). The wild African olive ( O. europaea subsp. cuspidata ) was introduced into Australia, New Zealand and Hawaii (Box 1; Cuneo and Leishman, 2006 ; Besnard et al. , 2014 ). Mediterranean and African subspecies have both become naturalized in south-east Australia ( Cuneo and Leishman, 2006 ; Cornuault et al. , 2015 ; ( Cuneo and Leishman, 2006 ; Cornuault et al. , 2015 ; Besnard and Cuneo, 2016 ). In this region, the selection of promising genotypes from naturalized olives has been reported ( Sedgley, 2004 ), and the possibility of introgression into these trees of material from subspecies cuspidata should be investigated (see below).

Domestication can be viewed as a window on human history, but also as a model for studying short-term species evolution and adaptation to different ecological conditions (i.e. natural ecosystems vs. agrosystems; Holliday et al. , 2017 ). Studies of the processes of adaptation in the context of domestication are also particularly relevant in terms of the crop community (pests, pathogens or symbionts), with frequent host shifts involving adaptation to new hosts following anthropogenic changes on the environment ( Stukenbrock and McDonald, 2008 ; Xing et al. , 2012 ; Gladieux et al. , 2015 ). In this context, olive is a relevant model for deciphering the evolutionary processes involved in perennial tree species adaptation at different temporal and spatial scales. Both archeological and genetic evidence has demonstrated that olive domestication involved multiple spatial and temporal steps, and that this process is still ongoing ( Besnard and Rubio de Casas, 2016 ; Díez and Gaut, 2016 ) as in several perennial species (e.g. Miller and Gross, 2011 ; Myles et al. , 2011 ; Delplancke et al. , 2013 ; Cornille et al. , 2014 ; Hazzouri et al. , 2015 ). However, a full understanding of this complex ecological process will require the elucidation of several aspects of the olive domestication. Indeed, while the major components of olive domestication are now relatively well established, several unanswered, or even unasked, questions remain to be addressed. (1) Can we detect a signature of selection associated with olive domestication, i.e. what are the traits and associated genes under selection in the cultivated olive? (2) Has there been any ecological shift between cultivated and wild olives? If so, with which ecological traits is it associated? (3) Was the associated community (e.g. pests, pathogens and symbionts) affected by olive domestication? Conversely, did the associated community play any role in olive domestication?

The answers to these questions lie in the analysis of signatures of adaptation at both the ecological and genomic levels, and neutral processes need to be taken into account through the accurate determination of olive demographic history (Box 3). Over the next few years, the flourishing of genomics methodologies has opened up new avenues of research for tackling these issues (e.g. McClure et al. , 2014 ; Plomion et al. , 2016 ; Holliday et al. , 2017 ; Migicovsky and Myles, 2017 ; see Supplementary Data Table S1 ).

The demographic history of olive: a prerequisite for investigations of the ecological genomics of olive domestication

Archeobiological perspectives for tracking the domesticated lineages..

Analyses of sub-fossil or archeological records will continue to shed light on the history of domesticated olives, particularly their human-mediated spread, and recent advances in archeogenetics and archeogenomics have opened up new perspectives for such studies (e.g. Elbaum et al. , 2006 ; Orlando et al. , 2015 ). Complete plastomes, mitogenomes and a draft of the nuclear genome are now available for olive ( Mariotti et al. , 2010 ; Besnard et al. , 2011 ; Cruz et al. , 2016 ; Unver et al. , 2017 ; Van de Paer et al. , 2018 ). These genomic materials should facilitate investigations of targeted genes or genomic regions of ancient DNA under selection during olive domestication, through the use of baiting methods ( Orlando et al. , 2015 ). Such approaches have already been used in maize ( da Fonseca et al. , 2015 ; Ramos-Madrigal et al. , 2016 ). For olive, single nucleotide polymorphisms (SNPs) have been used to track the spread of the main cultivar chlorotypes from the East to the West Mediterranean Basin (i.e. E1- e .1 and E1- e .2; Besnard et al. , 2013b ). The characterization of dated sub-fossils for such markers could help to clarify the timing of introduction of the Levantine cultivated lineage into different regions and to determine whether these introductions were linked to abrupt morphological changes in olive stones. These archeogenomic approaches may, however, encounter difficulties in the extraction of endogenous DNA from charred material, even with gene baiting methods ( Nistelberger et al. , 2016 ). This approach requires validation for organellar genomes, which should be the most amenable to such analyses due to their haploid nature, large numbers of copies per cell and available data concerning the distribution of their polymorphisms in current wild and cultivated olives.

The origin and parentage of cultivated clones.

Fine genetic characterization of ancient olive individuals on a regional scale may reveal a succession of principal cultivated genotypes (varieties) over time, with the replacement of some clones by others (e.g. new varieties grafted onto ancient ones), possibly due to past political or environmental changes. Monumental trees may, therefore, provide indications about the history of varieties, but it is essential to distinguish between rootstocks (wild or cultivated) and grafted genotypes (e.g. Dίez et al. , 2011 ; Barazani et al., 2014 , 2016 ; Chalak et al. , 2015 ; Lazović et al. , 2016 ). A high diversity would be expected for rootstocks, with mixtures of old varieties and oleaster, and the possibility of successive grafts onto the same tree (e.g. Baldoni et al. , 2006 ; Dίez et al. , 2011 ; Barazani et al., 2014 , 2016 ).

The combination of pedigree reconstruction or parentage analyses with studies of historical records of variety use should also shed light on the process of variety diversification at the regional scale, as already demonstrated in grape (e.g. Sefc et al. , 1998 ; Bowers et al. , 1999 ; Myles et al. , 2011 ). A few parentage analyses based on nuclear microsatellites have been reported for olive (e.g. Marra et al. , 2013 ), but this approach is sensitive to genotyping errors and possible mutations of such highly variable loci (e.g. Barazani et al. , 2014 ; Trujillo et al. , 2014 ). The discriminating power of genetic markers may also be lower in genepools that have undergone strong bottlenecks (especially Q1; Dίez et al. , 2015 ) and, in such cases, numerous unlinked loci (>30–50 microsatellites) may need to be used. With advances in sequencing technologies, thousands of SNPs are now available for the genotyping of olive varieties (e.g. Kaya et al. , 2013 ; Biton et al. , 2015 ; İpek et al. , 2016 ). SNPs are less variable than microsatellites, but they are considered to be more reliable (due to their great stability, easiness of scoring and a better understanding of their mutation rates), and this should make it possible to reconstruct robust pedigrees in the near future. Among the most ancient varieties, it may be possible to identify the major progenitors of current cultivars (e.g. Dίez et al. , 2015 ) and preferential crosses, as in grapes ( Bowers et al. , 1999 ).

The demographic history of wild and cultivated olives.

As stated above, the release of a draft genome for olive and recent advances in population genomics will make it possible to acquire large, affordable SNP data sets for further documentation of the timing and geography of olive domestication. Different hypotheses for single or multiple domestication events (Box 2) can be tested by computationally efficient population genomics methods developed for large SNP data sets (Box 3). The role of wild-to-crop and crop-to-crop gene flow in olive diversification also merits further investigation. In apples and grapes, wild-to-crop introgressions are key drivers of crop diversification ( Myles et al. , 2011 ; Cornille et al. , 2012 ). Wild-to-crop introgressions were clearly involved in variety diversification in Mediterranean olives (Box 2). Introgressions from non-Mediterranean subspecies may also have played a role (in both the native and introduced ranges). This question has never been addressed by whole-genome approaches. The early generation of hybrids was detected with a few molecular markers ( Besnard et al. , 2013a ; Besnard and El Bakkali, 2014 ), but the detection of more ancient footprints of introgression (>BC2) will require sequences or SNP data that are gradually becoming more accessible through the use of new sequencing technologies ( Supplementary Data Table S1 ). Crop-to-crop gene flow (i.e. admixture between differentiated cultivated gene pools) may also have contributed to olive diversification. The contribution of the eastern and western wild genepools to the three main cultivated genepools could be assessed by genomic scans to characterize the regions along the chromosomes that have contributed to the genome architecture of cultivated olives (e.g. Scascitelli et al. , 2010 ; Liu et al. , 2015 ). The use of whole-genome sequencing data would also make it possible to determine how many and which parts (and genes) of the genome have been subject to introgression, and whether or not these regions were selected during domestication (Box 3, and see below). The answers to these questions will not only provide fundamental insight into the olive domestication process, but will also help us to understand the genomic processes underlying short-term species divergence in perennials.

Investigating the ecological genomics of olive domestication and its impact on the associated biotic community

Which traits and genes were under selection during olive domestication.

The deciphering of the olive domestication process requires investigations of the impact of human selection on the genome architecture of the olive, including, in particular, the genes and alleles controlling agronomic traits (Box 3). As in other perennial crops, no strong domestication syndrome has been described in olive, and some varieties have been vegetatively propagated over long periods. Selection may therefore not have occurred, or may have been limited to the first few generations after the wild ancestors. This situation may account for the tenuous nature of the domestication syndrome described in many fruit crops, in stark contrast to that of seed-propagated annuals ( Glémin and Bataillon, 2009 ; McKey et al. , 2010 ; Zohary et al. , 2012 ; Gaut et al. , 2016 ). However, there is evidence to suggest that human selection may have led to the adaptive divergence of cultivated perennial crops from their wild relatives (e.g. Cornille et al. , 2014 ). In olive, human selection has resulted in phenotypic, ecological and genetic differences between oleaster and cultivated olives ( Table 1 ). It remains unclear whether or not these differences are adaptive, and further studies are therefore required to determine the genomic basis of olive domestication in an ecological context.

Recently developed genomic approaches ( Supplementary Data Table S1 ; Box 3) can detect footprints of positive selection on genes of agronomic importance (e.g. fruit size, organoleptic properties or tree architecture) and the signature of balancing selection for genes involved in resistance to pests and diseases (e.g. Verticillum , Phytophtora and olive fly). However, the detection of balancing selection on genes of advanced generations of admixed varieties remains challenging (e.g. Fijarczyk and Babik, 2015 ). Furthermore, the genes of the self-incompatibility (SI) system in olives may have been under strong selection during the process of cultivar selection (e.g. cultivation of compatible genotypes or selection of self-compatible mutants). An unusual sporophytic system with two compatibility groups has recently been described in the olive tribe ( Saumitou-Laprade et al. , 2017 ), but the genes and alleles involved have yet to be identified and their diversity has not been investigated in relation to cross-compatibility phenotypes (e.g. Breton et al. , 2014 ).

The recent release of a reference genome for olive and oleaster ( Cruz et al. , 2016 ; Unver et al. , 2017 ), together with new population genetic frameworks designed to search for molecular signatures of evolutionary processes and to infer complex demographic histories, have made studies of the genomic consequences of olive domestication timely. Resequencing of the genomes of both wild and cultivated olives (as in date palm, peach and almond; Hazzouri et al. , 2015 ; Velasco et al. , 2016 ) can now be used for comparative and population genomics approaches, to infer demographic history and then to test for a precise genomic signature of adaptation during olive domestication. In parallel, the diversity and evolution of olive-associated biotic communities can also be investigated. The combination of these genomic approaches will provide us with a more precise picture of the ecological and genomic consequences of olive domestication and, more generally, of adaptation in perennials.

When testing for signals of adaptation, a lack of knowledge of the demography of the species studied can greatly skew estimates of allele frequency ( Tiffin and Ross-Ibarra, 2014 ). It is therefore crucial to document and infer the demographic history of the model species. The history of olive cultivars can be reconstructed from sub-fossil data (archeogenomics) and current material (e.g. parentage analyses). Different hypotheses for single or multiple domestication events can then be tested with diffusion theory-based models of demographic history ( dady ; Gutenkunst et al. , 2009 ), MSMC ( Schiffels and Durbin, 2014 ) or by ABC ( Beaumont, 2010 ), as recently reported for several tree species ( Cornille et al. , 2012 ; Delplancke et al. , 2013 ; Besnard et al. , 2014 ; Gerbault et al. , 2014 ; Dίez et al. , 2015 ; Mayol et al. , 2015 ; Zhou et al. , 2017 ). Genetic erosion during cultivar selection must also be assessed, with recently developed population genomics methods created for use with whole-genome sequences from hundreds of individuals. In particular, pairwise or multiple sequentially Markovian coalescent (PSMC or MSMC) models can be used to infer changes in population size over time from SNP frequency spectra ( Liu and Fu, 2015 ). However, this method requires high-quality genome sequences (i.e. good sequencing coverage per site over the whole genome), to ensure that the estimated allele frequency spectra are accurate. The olive genome is relatively large (1.5–1.8 Gb; Cruz et al. , 2016 ), so such methods will entail high sequencing costs, and the varieties used must therefore be selected with care (e.g. on the basis of genepool membership – Q1, Q2 and Q3 – or ancient vs. recent cultivars; Gross et al. , 2014 ).

Methodological framework to address major questions on the impact of domestication on the evolution of olive and its associated biotic communities.

Recently developed methods can be used to detect different types of selection. These methods include genome scans for signatures of positive selection (e.g. Hufford et al. , 2012 ; Hoban et al. , 2016 ; Booker et al. , 2017 ), with the detection of hard or soft selective sweeps for candidate genes (e.g. Civáň et al. , 2015 ; Akagi et al. , 2016 ; Velasco et al. , 2016 ; Hermisson and Pennings, 2017 ), and/or balanced selection for traits affected by heterosis or conferring parasite resistance (e.g. Bento et al. , 2017 ). It will also be relevant to investigate whether the genes or genomic regions under positive selection detected have resulted from wild-to-crop gene flow.

The power to detect genes under positive selection associated with olive domestication will be enhanced by large-scale phenotyping efforts spanning multiple years in several environments and including replicates of wild and cultivated individuals in collections or common gardens (e.g. Belaj et al. , 2012 ; El Bakkali et al. , 2013 ; Ben Sadok et al. , 2015 ; León et al. , 2016 ). Over the last 10 years, segregating progenies have been used to identify genomic regions associated with agronomic traits [quantitative trait loci (QTLs) for olive oil quality, fruiting, growth and tree architecture], but the precise genes responsible for these trait variations remain unknown (e.g. Ben Sadok et al. , 2013 ; Atienza et al. , 2014 ; Pérez et al. , 2014 ). Genome-wide association studies (GWAS) with large SNP datasets associated with phenotypic agronomic traits will make it possible to identify genes displaying signatures of recent positive selection associated with phenotypic agronomic traits (e.g. Wright et al. , 2005 ; Migicovsky and Myles, 2017 ). These methods will require a consideration of olive history (e.g. cultivar filiation) and population structure (e.g. differentiated genepools or admixture; Segura et al. , 2012 ). In particular, the high degree of genetic differentiation between eastern and western wild genepools and the complex diversification of the crop will have to be taken into account, to prevent spurious correlations related to historical effects ( Tiffin and Ross-Ibarra, 2014 ). Finally, environmental association studies ( Rellstab et al. , 2015 ) would also make it possible to determine the contribution of local environmental factors to the adaptation of the cultivated olive, and to determine whether ecological differences led to the adaptive divergence between olive and oleaster.

Olive domestication may have led to pathogens or symbionts becoming adapted to their crop hosts. This hypothesis can be tested by applying the same methods described above for olive (i.e. comparative and association genomics) to the associated populations (microbes, nematodes and arthropods). In parallel, phylogeographic methods coupled to ecological modelling comparing isolated, long-standing oleaster populations and their pathogens (e.g. olive fly) in the Mediterranean Basin would provide information about the co-demographic histories of the interacting species in the adaptation test. Microbial communities may also have played a crucial role in olive domestication, and olive adaptation to local conditions, with reciprocal effects, but these issues have yet to be investigated. A first step in this direction would involve investigations of the diversity of bacterial or fungal communities, and its differences between environments and between cultivated and wild olives.

Bridging the gap between genomics and ecology to unravel the olive domestication process.

The ecological context of domestication has been much less studied than its genomic basis ( Milla et al. , 2015 ). One reason for this may be the ease with which genomic data can be generated and obtained nowadays, relative to the burden of harvesting ecological data in the field. In recent years, access to large environmental databases (e.g. http://worldclim.org/ ), together with niche modelling, has facilitated the characterization of bioclimatic niches for many species ( Guisan and Thuiller, 2005 ). The concerted advances in phenomics, genomics and ecological modelling have made it timely to bridge the gap between ecology and genomics to unravel olive domestication. In particular, the key role of climatic factors in the evolution of oleaster and cultivated olive during the Quaternary raises questions about the role of environmental conditions in shaping cultivated olive ecology, evolution and adaptation. Both in the wild (e.g. García-Verdugo et al., 2009 ; Granado-Yela et al. , 2011 ; Rubio de Casas et al. , 2011 ) and in common gardens ( Rubio de Casas et al. , 2011 ; Ben Sadok et al. , 2015 ; León et al. , 2016 ), strong environment effects have been demonstrated on many traits of wild olives and cross progeny. Little is known about the ecological and genomic basis of this phenotypic variation (e.g. Merilä and Hendry, 2014 ), but epigenetic determinants are likely involved (e.g. Platt et al. , 2015 ). Genome-wide association studies with phenotypic traits should help us to understand the genomic basis underlying this variation and its association with olive domestication. Characterization of the bioclimatic niches of wild and cultivated olives will also facilitate investigations of the possible role of ecological shifts in tolerance to abiotic conditions in olive domestication ( Milla et al. , 2015 ). Environmental genome-wide association studies ( Rellstab et al. , 2015 ) should also shed light on whether local environmental factors were responsible for this variation and the local adaptation of cultivated olives (Box 3), and whether ecological differences have led to adaptive divergence between olive and oleaster. Ecological and genomic approaches comparing introduced non-native olives and local native olives should also reveal how olive trees respond to their local environment. Over the last two centuries, the invasion of South and East Australia by two olive subspecies has resulted in a realized niche shift ( Cornuault et al. , 2015 ). Investigations of ecological and genomic differentiation between native and invasive populations should reveal whether this shift is adaptive or the result of plasticity. Overall, these association and environmental studies will make it possible to predict the ability of olives to adapt to current global warming and aridification of the area around the Mediterranean Sea ( Seager et al. , 2014 ), which will be crucial to the survival of these trees in the face of current global changes.

The ecological genomics of the ‘olive–biotic community’ interaction.

Olives have intimate symbiotic or antagonistic relationships (e.g. symbionts or pathogens) with the diverse biotic community with which they are associated (microbes, nematodes and arthropods). The influences of the components of this system on each other and the effects of domestication on their interactions are so far understudied in olive (Box 3). Investigations of this issue will provide fundamental insight into the ecological processes and genomic basis of coevolution at the community level. This issue is not only of fundamental academic importance, it will facilitate the adoption of appropriate cropping practices for pest or disease control (e.g. Paredes et al. , 2015 ; Decroocq et al. , 2016 ). The efficacy of root endophyte bacteria (e.g. Pseudomonas fluorescens ) as systemic biocontrol agents for a major fungal pathogen ( Verticilium dahliae ) has already been demonstrated in olive trees ( Prieto et al. , 2009 ; Aranda et al. , 2011 ; Gómez-Lama Cabanás et al. , 2014 ). Improvements in our understanding of olive ecology would help to unravel the history of such olive–microbe interaction and to predict its fate under future environmental and economic changes (e.g. Ponti et al. , 2014 ; Seager et al. , 2014 ).

Domestication may lead to significant changes in the evolutionary ecology of crop pathogens. For instance, crop domestication may involve the adaptation of pathogens to new hosts, or host switches from the wild to the crop (e.g. Gladieux et al. , 2010 ; Cornille et al. , 2014 ), potentially leading to an increase in pathogen virulence on the crop ( Lê Van et al. , 2012 ). In olive, human selection for genotypes with high growth and high fruit set rates may have had consequences for the defence responses of the cultivated olive ( Massei and Hartley, 2000 ) and for gene dispersal (e.g. abundant pollen from a few clones, limited dispersal of large fruits; Alcántara and Rey, 2003 ; Perea and Gutiérrez-Galán, 2016 ), in turn affecting the interaction of olive trees with other organisms. Furthermore, due to the relentless modernization of orchards, ancestral cultivars are increasingly being discarded in favour of a few highly productive varieties (e.g. Khadari et al. , 2008 ; Infante-Amate et al. , 2016 ). With a limited number of clones cultivated at high density, pathogen outbreaks become more likely. A few studies have provided a glimpse of the genetic basis of olive–pathogen interactions (e.g. Corrado et al. , 2012 ; Giampetruzzi et al. , 2016 ), but whole-genome data are nevertheless required to identify the genomic variants involved in olive–parasite interactions. For instance, genes controlling the synthesis of secondary metabolites by the olive tree may be good candidates for involvement in olive–parasite interactions worthy of further investigation (e.g. Hashmi et al. , 2015 ).

The microbial or microfaunal community associated with olive trees may also have been affected by olive domestication ( Montes-Borrego et al. , 2014 ; Ali et al. , 2017 ). A high diversity of bacteria has been reported to be associated with the root systems of wild olives in Andalusia, with plant genotype- and site-specific communities and potential antagonism of pathogens ( Aranda et al. , 2011 ). However, too few such studies have been performed to date, and investigations of the structure of communities in different areas and under different conditions (e.g. oleasters vs. cultivars, or traditional vs. high-density orchards) are required to determine the impact of olive domestication and cultivation practices on diversity and susceptibility (e.g. Ali et al. , 2017 ). Recent studies on nematodes ( Palomares-Rius et al. , 2012 , 2015 ; Ali et al. , 2017 ) and fungi ( Montes-Borrego et al. , 2014 ; Abdelfattah et al. , 2015 ) associated with cultivated olives have also shown these communities to be influenced by environmental factors (e.g. soil parameters and cropping methods) and host genotype. Future investigation of this type may be facilitated by the development of DNA metabarcoding methods (e.g. Montes-Borrego et al. , 2014 ; Abdelfattah et al. , 2015 ) for describing the microbial communities associated with different cultivars. In addition, common garden studies carried out by interdisciplinary research consortia from around the world (multiple sites in different countries) should also provide valuable assessments of the effect of olive genotypes on associated communities.

Adaptive processes and demographic events must be distinguished in investigations of the ecological genomics of biotic interactions. Investigations of co-demographic histories between olives and the communities associated with them are therefore a useful approach for unravelling the impact of domestication on the olive and its biotic community. The arthropod, nematode and microbial communities associated with the oleaster and other Mediterranean shrubs may have a common phylogeography due to host specificity or constrained evolutionary histories in common habitats that have been fragmented, particularly during unfavourable periods, such as glaciations (e.g. Nieto Feliner, 2014 ). Recent studies have shown that the diversification of the olive fly is closely related to that of its host ( Nardi et al. , 2010 ; van Ash et al., 2015 ) and the endophytic bacterial communities of olive leaves have also revealed an East–West geographic structure of beta-diversity ( Müller et al. , 2015 ). Recently developed comparative methods (e.g. Satler and Carstens, 2016 ) coupled with ecological modelling for isolated, long-standing oleaster populations and other organisms (e.g. nematodes or olive fly) in the Mediterranean Basin will constitute a first step towards accurate investigations of the adaptive genomics of olive–biota interaction.

Over the last two decades, the contributions of several disciplines have improved our understanding of the processes of domestication, spread and diversification, for olive, as for other fruit trees and shrubs (e.g. Myles et al. , 2011 ; Delplancke et al. , 2013 ; Cornille et al. , 2014 ; Hazzouri et al. , 2015 ). The olive is a complex case study in fruit tree domestication. From methodological and analytical perspectives, deciphering the adaptive evolutionary processes involved in olive domestication remains challenging. More than ever, ecological and socio-economic issues relating to the future of the olive are fundamental in light of current global changes (climatic, societal, political, economic, etc.), particularly in the Mediterranean Basin, the cradle of olive domestication (e.g. Ponti et al. , 2014 ). Interdisciplinary research is a key element for (1) understanding the functioning of oleaster communities and assessing their vulnerability/resilience in the face of increasing environmental constraints, predominantly of climatic and anthropogenic origin; (2) reconstituting the paleoanthropological, ecological and biogeographic history of the olive tree; (3) exploring agrobiodiversity and understanding the ecological plasticity of varieties of major interest; (4) developing strategies for the conservation of wild olive populations and development of local varieties; and (5) understanding the role of social, political and economic processes in the diversification and development of sustainable olive cultivation. A detailed knowledge of the origins of olive would have major implications for the management of genetic resources and the investigation of genetic factors involved in the variation of agronomic traits and, more generally, would provide insight into fruit tree domestication in the Mediterranean Basin.

The aim of our review was not to be all inclusive but rather to be selective with the up to date literature. Throughout it, we have shown, that unravelling the ecological genomics of olive domestication will also provide essential insight into the evolutionary processes involved in phenotypic and molecular evolution, and in adaptation and coevolution.

Supplementary data are available at https://academic.oup.com/aob and consist of the following. Table S1: summary of the current genetic data used to infer histories of cultivated and wild olives, with associated methodologies, limitations and main conclusions, and the future genomic data required to test for the neutral and adaptive genomics of domestication in olive. Table S2: data matrix for the 147 plastid DNA haplotypes identified in the olive complex with 71 loci. Figure S1: reduced median networks of Mediterranean olive plastid DNA haplotypes. Fig. S2: median joining network of olive chlorotypes reconstructed with NETWORK.

We thank the members of the EDB laboratory for fruitful discussions and, particularly, D. Kaniewski, J. Hackel, C. Van de Paer and J. Bruxaux and G. Volk. We also thank P. Cuneo, R. Rubio de Casas and E. Chapuis for helpful comments. G.B. is supported by TULIP (ANR-10-LABX-0041), CEBA (ANR-10-LABX-25-01) and PESTOLIVE (ARIMNet action KBBE 219262).

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Charles Eisenstein

Olive Trees and the Cry of the Land

May 30, 2018 by Charles Eisenstein

The olive trees are dying in the Salento region of Italy, the picturesque heel of the Italian peninsula.

A new disease called Olive Quick Decline Syndrome (OQDS) is ravaging olive groves that date back to Roman times and before, some with 2000-year-old trees. Leaves wither as is scorched by fire, twigs and branches die back, and the trees quickly die.

Two theories have emerged to explain this calamity, two stories. Each exemplifies a more general relationship between humans and the material world, with consequences far beyond Italian olive trees.

The first and dominant theory says that OQDS is caused by a bacterium, Xylella fastidiosa , which was introduced via an infected oleander from Costa Rica. Fortunately (according to this narrative), the authorities acted quickly by declaring a state of emergency, assigning European Commission funds to support research and eradication, and designating infected zones, buffer zones, and contagion-free zones. An extraordinary commissioner was appointed to enforce measures to prevent the contagion from spreading. Farmers were required to uproot all infected trees or face a 3000 penalty; all trees within 100 meters of an infected tree are to be cut down, entailing the destruction of entire groves. According to local activists, at present, some one-million trees are slated for destruction.

Not to worry – science has come to save the day. Researchers have developed a biopatented tree,    the F-17, the so-called “Favolosa” – that is permitted to be replanted in infected areas. In contrast to traditional biodiverse olive groves with centuries-old or millennia-old trees, these are grown in superintensive industrially farmed hedges of small trees, with extensive use of pesticides.

The Xylella theory names insects such as the meadow spittlebug as the transmission vectors for the bacteria; accordingly, authorities are pushing for the elimination of all ground vegetation around the olive trees to deprive the insects of habitat, as well as the heavy use of insecticides. The model is a monoculture of olive trees on bare soil. Maybe a few of the majestic 2000-year-old trees can be preserved for tourism.

A second theory has been advanced by Margherita Ciervo of the University of Foggia, among other researchers. It says that Xylella infection is a symptom, and not a cause, of OQDS, and that it may not even be an exogenous species. It opportunistically breaks out in the presence of what these researchers name as the deeper causes: primarily, the degradation of soil due to poor agricultural practices. For example, even in older groves, growers in recent years have made heavy use of glyphosate and other herbicides to remove ground-cover to allow easier harvesting. The dead, compacted soil no longer harbors the microbiota that contribute to the trees’ resistance to fungi and bacteria (some believe that fungi are actually the main immediate culprit, not Xylella ). Water absorption is also diminished, making the trees more susceptible to drought. Ciervo blames the broad-spectrum herbicide glyphosate in particular. Quoting a 2009 paper by Johal & Huber in the European Journal of Agronomy , she writes:

“various diseases caused by X. fastidiosa are referred to as ‘emerging’ or ‘reemerging’ diseases as glyphosate weed management programs for their respective crops have intensified. These diseases (Pierce’s disease of grapevine, plum scorch, almond scorch, citrus variegated chlorosis, coffee blight, citrus blight, alfalfa dwarf, pecan decline, etc.) are characterized by a loss of vigor, slow decline, micronutrient deficiency, and reduced productivity. The pathogen is an endophytic bacterium that colonizes xylem tissues and restricts nutrient translocation when plants are stressed […] Glyphosate stimulation of fungal growth and enhanced virulence of pathogens such as Fusarium , Gaeumannomyces , Phytophthora , Pythium , and Xylella can have serious consequences for sustainable production of a wide range of susceptible crops and lead to the functional loss of genetic resistance.

To establish her hypothesis that OQDS affects trees weakened by pesticide poisoning, Ciervo surveyed the distribution of the syndrome and correlated it with the prevalence of organically cultivated land, confirming that the more organic agriculture there is in an area, the less affected it is by OQDS. Her finding confirms the experiences of organic farmers in the region who have revived their trees or avoided contagion altogether, as vividly displayed in this video from an Italian farmer comparing his organic groves to the chemically-farmed groves of his neighbor.

Which of these two theories is true? Obviously I am partial to the latter theory, but in fact, careful consideration shows they are not entirely contradictory. It depends on the context and on what is taken for granted. In the context of chemical-intensive conventional olive production, Xylella is indeed a serious threat. If we take for granted the continuation of that system of agriculture, then the measures the authorities have implemented are necessary. They need be neither corrupt nor stupid to pursue the program of pesticides and eradication. The OQDS, therefore, opens up the larger question of what kind of agricultural system do we want to promote.

The solutions implemented by local organic growers, such as mineral supplementation, microbiome restoration, proper pruning, and the maintenance of biodiverse plant and animal ecosystems in olive groves, have in common a glaring problem. They are economically inefficient in the context of the global market. Farmers using these methods will never be able to compete in conventional commodity markets against industrial plantations.

A new government has come into power in Italy with the wherewithal to halt the eradication campaign and adopt policies based on the deeper understanding outlined above. However, let us not underestimate the difficulty of doing so. Italian olive oil production was in crisis well before the OQDS outbreak. Low-cost North African plantations, in many cases run by large multinational corporations, have already made traditional Italian production uneconomic. According to journalist Petra Reski, it was, in part, to compete against the North African plantations, which use precisely the aforementioned water-intensive, chemical-intensive monocrop hedges of small trees replanted every 15 years, that Italian growers began using glyphosate in the first place.

The deeper context here is the commodification and globalization of agriculture – a trend which the Italian Five Star Movement, however radical, has limited power to reverse on its own. The new government can, however, listen to the experiences of organic farmers and researchers like Margherita Ciervo and implement policies that may serve a more general transition to sustainable and regenerative agriculture, and preserve the cultural/ecological treasure that is Italy’s ancient olive groves. Let me suggest a policy program to accomplish this:

(1) First, immediately halt the eradication and pesticide campaign, which exacerbates the conditions that make Xylella a problem.

(2) Transition Italian olive production to a fully organic system and create a ‘brand identity” that associates Italian olive oil with the flavor, health, and ecological advantages of mature trees on healthy land. (Oil from these trees has superior flavor and twice the polyphenols of industrially cultivated olive oil.)

(3) Shift agricultural subsidies to support ecological olive cultivation, perhaps by implementing ecosystem services payments to farmers in recognition of the public benefits of water-conserving, environmentally benign traditional organic cultivation.

(4) Work toward international agreements to restrict unsustainable, ecologically disruptive, water-hogging agricultural practices in olive cultivation and beyond, so as to level the playing field for sustainable producers.

Currently, there is considerable momentum in the other direction. Powerful interests have a lot to gain from the eradication campaign, which opens land to development of resorts, golf courses, etc. that had been protected due to the presence of historic trees. The pesticide companies, university agronomy departments, and biopatent holders also benefit. There is little institutional support for research into alternative theories, a prospect made even more difficult because infected tree parts are considered biohazards and are only permitted to be tested at a single designated laboratory representing the mainstream position.

Facing powerful institutions and cut off from the possibility of scientific confirmation of their viewpoint, activists and farmers seeking to preserve the trees are ridiculed in the media with terms like “magicians,” “superstitious,” and “gurus.” But it is not that they are fundamentally unscientific; it is that the science that could support them lacks the funding and institutional support to develop.

The Xylella hypothesis sits comfortably with the interests of multinational agribusiness and validates current trends toward the hyper-industrialization of agriculture. It also conforms to more general intellectual and political habits of our civilization. It is linear and reductionistic, seeking a single cause rather than understanding reality as a complex system. It exemplifies the find-an-enemy approach to problem-solving that is always looking for something to control, something to imprison, or something to kill. I find in the whole affair an echo of European anxiety about immigration: a rush to blame a foreign intruder while ignoring underlying causes. In the case of immigration, these include neoliberal economic policies and military imperialism, making other countries unlivable. In the case of the olive trees, similarly, they include the chemical assault on the soil that makes it, too, unlivable.

Where the conventional perspective on the olive tree deaths is that a killer bacteria is attacking them, we might view it differently: as the cry of the land, calling our attention to its suffering. Shall we listen to that cry? Or shall we continue to add to its suffering?

The OQDS issue offers a special opportunity to inaugurate a shift in our perceptions, methods, and policies. While it may seem a narrow issue in the context of our many global crises, the response to it sets the tone for responses to other situations in which we must choose between, on the one hand, waging war against the most readily identifiable bad guy, and on the other hand, seeking to understand and heal the ground conditions from which the “bad guy” arises. In addition, the response to OQDS will either further normalize the industrial, chemical-intensive, globalized system of commodity agriculture, or it will showcase an alternative to that system. Italy and the European Commission face a potent moment of choice here. We can hope that the beauty and cultural resonance of the ancient trees will inspire the courage necessary to chart a new course.

Before/after video of destroyed grove: https://www.facebook.com/enzo.suma.1/videos/10216048064024110/

Interview with scientific opponents of the extermination(Italian language): https://www.youtube.com/watch?v=6pa1hu-5szk

https://www.youtube.com/watch?v=7t-Wk08VeX8&t=5513s

Organic olive grower Roberto Polo (Italian language): https://www.youtube.com/watch?v=AXdbb4xrImQ

Reader Interactions

May 30, 2018 at 1:50 pm

Hi, Charles, Once again you spoke to the heart of the problem. I live in the heart of California industrial agriculture south of Fresno. I work at a charter school out in the country. I look out my office window across a fence 15 feet from my window into an orange orchard whose soil despite irrigation is weedless with only a scattering of brown leaves., empty of animals, and people. People seen only at harvest, spraying, and pruning. The tree are a particular variety favored in Japan and so exported at a good price . The woman in the office next to me once started to farm organically a citrus orchard with sheep. goats and chickens integrated into the system. In a few years the depleted soil blossomed, became soft and friable, eventually she needed little if any fertilization, her neighbors thanked her for the natural pest control that benefited them, birds and wild animals roamed the property, the fruit was unusually flavorable and sold around the nation mail order to individuals and families. Many of her trees were old strain Washington Navels no longer planted that have from my experience and hers a superior flavor BUT, her orchard required more intensive human contact and management than the same acreage done conventionally, even with the organic price premium money was inadequate for sufficient hired help, and once her three sons moved away her husband couldn’t handle the work and they sold the property and moved to town. The Washing ton Navels were pulled out by the new owners. Like most people I want to pay as little as possible for food, actually not pay the real price for food that is good in every aspect – socially, ecologically, and so on. The effect of this short sighted impulse translates into our industrial agriculture system. Now something fun. We are doing a natural landscaping effort on our 7 acres of charter school property using native plants and appropriate drought tolerant non-natives. We have already won a couple awards. The next year I hope to build with our students a 55 foot wide circular labyrinth planted with wonderful drought tolerants on the gentle mounds between the paths with a Polo Verde tree shading the center. Take care,

May 30, 2018 at 4:13 pm

Jeff, I live in Auberry, in the foothills just East of Fresno. Would it be possible for us to connect? 559 270-5193

May 19, 2019 at 11:32 am

Jeff, we once worked on a circular herb garden in Covelo w Alan Chadwick, so I am partial to your school project. But he had it descending to a center pool ring by ring w stone paths. The deep bed Indigenous agriculture being taught in Central America by Mel Landers (see Soil4Climate FB page) has deep paths w dikes at ends to hold winter rains and is all mulch oriented on top of beds. He has an online link to his manual as I recall. Would be worth a course in itself for the students.

Good job. James Ryan

May 30, 2018 at 2:18 pm

HI Charles, Thank you for writing this post. It may seem like a niche or random topic , which might make you feel like it won’t have broad appeal to your audience. However, that is not how I experienced it. I actually think it’s more important to highlight how our linear thinking is playing out in what seem like minor ways because it creates tangible examples that the layman can explore. It also makes it feel solvable, whereas when we talk about your theories in the context of big global problems it can become confusing and feel hopeless. I can actually use this example with people outside the tribe (which I can’t do yet with hairy topics like immigration). As a side note, it’s also something that I can present in a more objective way (we can all be open to discussing olive trees because very few of us have emotional charge connected to saving them). Anyway, my point for writing is to say, don’t shy away from these niche topics, this is helpful. Thank you!

June 5, 2018 at 12:53 am

Thanks, Charles, for all the thoughtful insights you share here as well as in your books and other teachings. They are a gift to the world. May we gracefully transition to a more beautiful world!

I just want to share a, perhaps, nit-picky piece of feedback about your website. When I go to read your articles after you send a link to them, I do so on Chrome browser. The words to your blogs are right next to the very edge of the page, not even an 1/8th of an inch of space, and it’s a bit challenging for my eyes to take it in. I just tested it on Safari and that’s better… seems there’s at least a 1/4 of an inch there. I’m not sure if there’s anything that can be done about this but if so, it might be good for me as well as others.

In the meantime, now that I know it’s better on Safari, I’ll try to remember to open your blogs on that browser.

Best wishes to you, Beeara

January 23, 2020 at 5:22 am

Hi Charles, have you followed up on this? Sounds like another missed crises opportunity to change directions

The Coronation

For years, normality has been stretched nearly to its breaking point, a rope pulled tighter and tighter, waiting for a nip of the black swan’s beak to snap it in two. Now that the rope has snapped, do we tie its ends back together, or shall we undo its dangling braids still further, to see what we might weave from them?

Covid-19 is showing us that when humanity is united in common cause, phenomenally rapid change is possible. None of the world’s problems are technically difficult to solve; they originate in human disagreement. In coherency, humanity’s creative powers are boundless. A few months ago, a proposal to halt commercial air travel would have seemed preposterous. Likewise for the radical changes we are making in our social behavior, economy, and the role of government in our lives. Covid demonstrates the power of our collective will when we agree on what is important. What else might we achieve, in coherency? What do we want to achieve, and what world shall we create? That is always the next question when anyone awakens to their power.

Covid-19 is like a rehab intervention that breaks the addictive hold of normality. To interrupt a habit is to make it visible; it is to turn it from a compulsion to a choice. When the crisis subsides, we might have occasion to ask whether we want to return to normal, or whether there might be something we’ve seen during this break in the routines that we want to bring into the future. We might ask, after so many have lost their jobs, whether all of them are the jobs the world most needs, and whether our labor and creativity would be better applied elsewhere. We might ask, having done without it for a while, whether we really need so much air travel, Disneyworld vacations, or trade shows. What parts of the economy will we want to restore, and what parts might we choose to let go of? And on a darker note, what among the things that are being taken away right now – civil liberties, freedom of assembly, sovereignty over our bodies, in-person gatherings, hugs, handshakes, and public life – might we need to exert intentional political and personal will to restore?

For most of my life, I have had the feeling that humanity was nearing a crossroads. Always, the crisis, the collapse, the break was imminent, just around the bend, but it didn’t come and it didn’t come. Imagine walking a road, and up ahead you see it, you see the crossroads. It’s just over the hill, around the bend, past the woods. Cresting the hill, you see you were mistaken, it was a mirage, it was farther away than you thought. You keep walking. Sometimes it comes into view, sometimes it disappears from sight and it seems like this road goes on forever. Maybe there isn’t a crossroads. No, there it is again! Always it is almost here. Never is it here.

Now, all of a sudden, we go around a bend and here it is. We stop, hardly able to believe that now it is happening, hardly able to believe, after years of confinement to the road of our predecessors, that now we finally have a choice. We are right to stop, stunned at the newness of our situation. Because of the hundred paths that radiate out in front of us, some lead in the same direction we’ve already been headed. Some lead to hell on earth. And some lead to a world more healed and more beautiful than we ever dared believe to be possible.

I write these words with the aim of standing here with you – bewildered, scared maybe, yet also with a sense of new possibility – at this point of diverging paths. Let us gaze down some of them and see where they lead.

I heard this story last week from a friend. She was in a grocery store and saw a woman sobbing in the aisle. Flouting social distancing rules, she went to the woman and gave her a hug. “Thank you,” the woman said, “that is the first time anyone has hugged me for ten days.”

Going without hugs for a few weeks seems a small price to pay if it will stem an epidemic that could take millions of lives. There is a strong argument for social distancing in the near term: to prevent a sudden surge of Covid cases from overwhelming the medical system. I would like to put that argument in a larger context, especially as we look to the long term. Lest we institutionalize distancing and reengineer society around it, let us be aware of what choice we are making and why.

The same goes for the other changes happening around the coronavirus epidemic. Some commentators have observed how it plays neatly into an agenda of totalitarian control. A frightened public accepts abridgments of civil liberties that are otherwise hard to justify, such as the tracking of everyone’s movements at all times, forcible medical treatment, involuntary quarantine, restrictions on travel and the freedom of assembly, censorship of what the authorities deem to be disinformation, suspension of habeas corpus, and military policing of civilians. Many of these were underway before Covid-19; since its advent, they have been irresistible. The same goes for the automation of commerce; the transition from participation in sports and entertainment to remote viewing; the migration of life from public to private spaces; the transition away from place-based schools toward online education, the decline of brick-and-mortar stores, and the movement of human work and leisure onto screens. Covid-19 is accelerating preexisting trends, political, economic, and social.

While all the above are, in the short term, justified on the grounds of flattening the curve (the epidemiological growth curve), we are also hearing a lot about a “new normal”; that is to say, the changes may not be temporary at all. Since the threat of infectious disease, like the threat of terrorism, never goes away, control measures can easily become permanent. If we were going in this direction anyway, the current justification must be part of a deeper impulse. I will analyze this impulse in two parts: the reflex of control, and the war on death. Thus understood, an initiatory opportunity emerges, one that we are seeing already in the form of the solidarity, compassion, and care that Covid-19 has inspired.

The Reflex of Control

At the current writing, official statistics say that about 25,000 people have died from Covid-19. By the time it runs its course, the death toll could be ten times or a hundred times bigger, or even, if the most alarming guesses are right, a thousand times bigger. Each one of these people has loved ones, family and friends. Compassion and conscience call us to do what we can to avert unnecessary tragedy. This is personal for me: my own infinitely dear but frail mother is among the most vulnerable to a disease that kills mostly the aged and the infirm.

What will the final numbers be? That question is impossible to answer at the time of this writing. Early reports were alarming; for weeks the official number from Wuhan, circulated endlessly in the media, was a shocking 3.4%. That, coupled with its highly contagious nature, pointed to tens of millions of deaths worldwide, or even as many as 100 million. More recently, estimates have plunged as it has become apparent that most cases are mild or asymptomatic. Since testing has been skewed towards the seriously ill, the death rate has looked artificially high. In South Korea, where hundreds of thousands of people with mild symptoms have been tested, the reported case fatality rate is around 1%. In Germany , whose testing also extends to many with mild symptoms, the fatality rate is 0.4%. A recent paper in the journal Science argues that 86% of infections have been undocumented, which points to a much lower mortality rate than the current case fatality rate would indicate.

The story of the Diamond Princess cruise ship bolsters this view. Of the 3,711 people on board, about 20% have tested positive for the virus; less than half of those had symptoms, and eight have died. A cruise ship is a perfect setting for contagion, and there was plenty of time for the virus to spread on board before anyone did anything about it, yet only a fifth were infected. Furthermore, the cruise ship’s population was heavily skewed (as are most cruise ships) toward the elderly : nearly a third of the passengers were over age 70, and more than half were over age 60. A research team concluded from the large number of asymptomatic cases that the true fatality rate in China is around 0.5%. That is still five times higher than flu. Based on the above (and adjusting for much younger demographics in Africa and South and Southeast Asia) my guess is about 200,000-300,000 deaths in the US – more if the medical system is overwhelmed, less if infections are spread out over time – and 3 million globally. Those are serious numbers. Not since the Hong Kong Flu pandemic of 1968/9 has the world experienced anything like it.

My guesses could easily be off by an order of magnitude. Every day the media reports the total number of Covid-19 cases, but no one has any idea what the true number is, because only a tiny proportion of the population has been tested. If tens of millions have the virus, asymptomatically, we would not know it. Further complicating the matter is the high rate of false positives for existing testing, possibly as high as 80%. (And see here for even more alarming uncertainties about test accuracy.) Let me repeat: no one knows what is really happening, including me. Let us be aware of two contradictory tendencies in human affairs. The first is the tendency for hysteria to feed on itself, to exclude data points that don’t play into the fear, and to create the world in its image. The second is denial, the irrational rejection of information that might disrupt normalcy and comfort. As Daniel Schmactenberger asks , How do you know what you believe is true?

In the face of the uncertainty, I’d like to make a prediction: The crisis will play out so that we never will know. If the final death tally, which will itself be the subject of dispute, is lower than feared, some will say that is because the controls worked. Others will say it is because the disease wasn’t as dangerous as we were told.

To me, the most baffling puzzle is why at the present writing there seem to be no new cases in China. The government didn’t initiate its lockdown until well after the virus was established. It should have spread widely during Chinese New Year, when every plane, train, and bus is packed with people traveling all over the country. What is going on here? Again, I don’t know, and neither do you.

Whether the final global death toll is 50,000 or 500,000 or 5 million, let’s look at some other numbers to get some perspective. My point is NOT that Covid isn’t so bad and we shouldn’t do anything. Bear with me. Last year, according to the FAO , five million children worldwide died of hunger (among 162 million who are stunted and 51 million who are wasted). That is 200 times more people than have died so far from Covid-19, yet no government has declared a state of emergency or asked that we radically alter our way of life to save them. Nor do we see a comparable level of alarm and action around suicide – the mere tip of an iceberg of despair and depression – which kills over a million people a year globally and 50,000 in the USA. Or drug overdoses, which kill 70,000 in the USA, the autoimmunity epidemic, which affects 23.5 million (NIH figure) to 50 million (AARDA), or obesity, which afflicts well over 100 million. Why, for that matter, are we not in a frenzy about averting nuclear armageddon or ecological collapse, but, to the contrary, pursue choices that magnify those very dangers?

Please, the point here is not that we haven’t changed our ways to stop children from starving, so we shouldn’t change them for Covid either. It is the contrary: If we can change so radically for Covid-19, we can do it for these other conditions too. Let us ask why are we able to unify our collective will to stem this virus, but not to address other grave threats to humanity. Why, until now, has society been so frozen in its existing trajectory?

The answer is revealing. Simply, in the face of world hunger, addiction, autoimmunity, suicide, or ecological collapse, we as a society do not know what to do. Our go-to crisis responses, all of which are some version of control, aren’t very effective in addressing these conditions. Now along comes a contagious epidemic, and finally we can spring into action. It is a crisis for which control works: quarantines, lockdowns, isolation, hand-washing; control of movement, control of information, control of our bodies. That makes Covid a convenient receptacle for our inchoate fears, a place to channel our growing sense of helplessness in the face of the changes overtaking the world. Covid-19 is a threat that we know how to meet. Unlike so many of our other fears, Covid-19 offers a plan.

Our civilization’s established institutions are increasingly helpless to meet the challenges of our time. How they welcome a challenge that they finally can meet. How eager they are to embrace it as a paramount crisis. How naturally their systems of information management select for the most alarming portrayals of it. How easily the public joins the panic, embracing a threat that the authorities can handle as a proxy for the various unspeakable threats that they cannot.

Today, most of our challenges no longer succumb to force. Our antibiotics and surgery fail to meet the surging health crises of autoimmunity, addiction, and obesity. Our guns and bombs, built to conquer armies, are useless to erase hatred abroad or keep domestic violence out of our homes. Our police and prisons cannot heal the breeding conditions of crime. Our pesticides cannot restore ruined soil. Covid-19 recalls the good old days when the challenges of infectious diseases succumbed to modern medicine and hygiene, at the same time as the Nazis succumbed to the war machine, and nature itself succumbed, or so it seemed, to technological conquest and improvement. It recalls the days when our weapons worked and the world seemed indeed to be improving with each technology of control.

What kind of problem succumbs to domination and control? The kind caused by something from the outside, something Other. When the cause of the problem is something intimate to ourselves, like homelessness or inequality, addiction or obesity, there is nothing to war against. We may try to install an enemy, blaming, for example, the billionaires, Vladimir Putin, or the Devil, but then we miss key information, such as the ground conditions that allow billionaires (or viruses) to replicate in the first place.

If there is one thing our civilization is good at, it is fighting an enemy. We welcome opportunities to do what we are good at, which prove the validity of our technologies, systems, and worldview. And so, we manufacture enemies, cast problems like crime, terrorism, and disease into us-versus-them terms, and mobilize our collective energies toward those endeavors that can be seen that way. Thus, we single out Covid-19 as a call to arms, reorganizing society as if for a war effort, while treating as normal the possibility of nuclear armageddon, ecological collapse, and five million children starving.

The Conspiracy Narrative

Because Covid-19 seems to justify so many items on the totalitarian wish list, there are those who believe it to be a deliberate power play . It is not my purpose to advance that theory nor to debunk it, although I will offer some meta-level comments. First a brief overview.

The theories (there are many variants) talk about Event 201 (sponsored by the Gates Foundation, CIA, etc. last September), and a 2010 Rockefeller Foundation white paper detailing a scenario called “Lockstep,” both of which lay out the authoritarian response to a hypothetical pandemic. They observe that the infrastructure, technology, and legislative framework for martial law has been in preparation for many years. All that was needed, they say, was a way to make the public embrace it, and now that has come. Whether or not current controls are permanent, a precedent is being set for:

• • The tracking of people’s movements at all times (because coronavirus)
• • The suspension of freedom of assembly (because coronavirus)
• • The military policing of civilians (because coronavirus)
• • Extrajudicial, indefinite detention (quarantine, because coronavirus)
• • The banning of cash (because coronavirus)
• • Censorship of the Internet (to combat disinformation, because coronavirus)
• • Compulsory vaccination and other medical treatment, establishing the state’s sovereignty over our bodies (because coronavirus)
• • The classification of all activities and destinations into the expressly permitted and the expressly forbidden (you can leave your house for this, but not that), eliminating the un-policed, non-juridical gray zone. That totality is the very essence of totalitarianism. Necessary now though, because, well, coronavirus.

This is juicy material for conspiracy theories. For all I know, one of those theories could be true; however, the same progression of events could unfold from an unconscious systemic tilt toward ever-increasing control. Where does this tilt come from? It is woven into civilization’s DNA. For millennia, civilization (as opposed to small-scale traditional cultures) has understood progress as a matter of extending control onto the world: domesticating the wild, conquering the barbarians, mastering the forces of nature, and ordering society according to law and reason. The ascent of control accelerated with the Scientific Revolution, which launched “progress” to new heights: the ordering of reality into objective categories and quantities, and the mastering of materiality with technology. Finally, the social sciences promised to use the same means and methods to fulfill the ambition (which goes back to Plato and Confucius) to engineer a perfect society.

Those who administer civilization will therefore welcome any opportunity to strengthen their control, for after all, it is in service to a grand vision of human destiny: the perfectly ordered world, in which disease, crime, poverty, and perhaps suffering itself can be engineered out of existence. No nefarious motives are necessary. Of course they would like to keep track of everyone – all the better to ensure the common good. For them, Covid-19 shows how necessary that is. “Can we afford democratic freedoms in light of the coronavirus?” they ask. “Must we now, out of necessity, sacrifice those for our own safety?” It is a familiar refrain, for it has accompanied other crises in the past, like 9/11.

To rework a common metaphor, imagine a man with a hammer, stalking around looking for a reason to use it. Suddenly he sees a nail sticking out. He’s been looking for a nail for a long time, pounding on screws and bolts and not accomplishing much. He inhabits a worldview in which hammers are the best tools, and the world can be made better by pounding in the nails. And here is a nail! We might suspect that in his eagerness he has placed the nail there himself, but it hardly matters. Maybe it isn’t even a nail that’s sticking out, but it resembles one enough to start pounding. When the tool is at the ready, an opportunity will arise to use it.

And I will add, for those inclined to doubt the authorities, maybe this time it really is a nail. In that case, the hammer is the right tool – and the principle of the hammer will emerge the stronger, ready for the screw, the button, the clip, and the tear.

Either way, the problem we deal with here is much deeper than that of overthrowing an evil coterie of Illuminati. Even if they do exist, given the tilt of civilization, the same trend would persist without them, or a new Illuminati would arise to assume the functions of the old.

True or false, the idea that the epidemic is some monstrous plot perpetrated by evildoers upon the public is not so far from the mindset of find-the-pathogen. It is a crusading mentality, a war mentality. It locates the source of a sociopolitical illness in a pathogen against which we may then fight, a victimizer separate from ourselves. It risks ignoring the conditions that make society fertile ground for the plot to take hold. Whether that ground was sown deliberately or by the wind is, for me, a secondary question.

What I will say next is relevant whether or not SARS-CoV2 is a genetically engineered bioweapon, is related to 5G rollout, is being used to prevent “disclosure,” is a Trojan horse for totalitarian world government, is more deadly than we’ve been told, is less deadly than we’ve been told, originated in a Wuhan biolab, originated at Fort Detrick , or is exactly as the CDC and WHO have been telling us. It applies even if everyone is totally wrong about the role of the SARS-CoV-2 virus in the current epidemic. I have my opinions, but if there is one thing I have learned through the course of this emergency is that I don’t really know what is happening. I don’t see how anyone can, amidst the seething farrago of news, fake news, rumors, suppressed information, conspiracy theories, propaganda, and politicized narratives that fill the Internet. I wish a lot more people would embrace not knowing. I say that both to those who embrace the dominant narrative, as well as to those who hew to dissenting ones. What information might we be blocking out, in order to maintain the integrity of our viewpoints? Let’s be humble in our beliefs: it is a matter of life and death.

The War on Death

My 7-year-old son hasn’t seen or played with another child for two weeks. Millions of others are in the same boat. Most would agree that a month without social interaction for all those children a reasonable sacrifice to save a million lives. But how about to save 100,000 lives? And what if the sacrifice is not for a month but for a year? Five years? Different people will have different opinions on that, according to their underlying values.

Let’s replace the foregoing questions with something more personal, that pierces the inhuman utilitarian thinking that turns people into statistics and sacrifices some of them for something else. The relevant question for me is, Would I ask all the nation’s children to forego play for a season, if it would reduce my mother’s risk of dying, or for that matter, my own risk? Or I might ask, Would I decree the end of human hugging and handshakes, if it would save my own life? This is not to devalue Mom’s life or my own, both of which are precious. I am grateful for every day she is still with us. But these questions bring up deep issues. What is the right way to live? What is the right way to die?

The answer to such questions, whether asked on behalf of oneself or on behalf of society at large, depends on how we hold death and how much we value play, touch, and togetherness, along with civil liberties and personal freedom. There is no easy formula to balance these values.

Over my lifetime I’ve seen society place more and more emphasis on safety, security, and risk reduction. It has especially impacted childhood: as a young boy it was normal for us to roam a mile from home unsupervised – behavior that would earn parents a visit from Child Protective Services today. It also manifests in the form of latex gloves for more and more professions; hand sanitizer everywhere; locked, guarded, and surveilled school buildings; intensified airport and border security; heightened awareness of legal liability and liability insurance; metal detectors and searches before entering many sports arenas and public buildings, and so on. Writ large, it takes the form of the security state.

The mantra “safety first” comes from a value system that makes survival top priority, and that depreciates other values like fun, adventure, play, and the challenging of limits. Other cultures had different priorities. For instance, many traditional and indigenous cultures are much less protective of children, as documented in Jean Liedloff’s classic, The Continuum Concept . They allow them risks and responsibilities that would seem insane to most modern people, believing that this is necessary for children to develop self-reliance and good judgement. I think most modern people, especially younger people, retain some of this inherent willingness to sacrifice safety in order to live life fully. The surrounding culture, however, lobbies us relentlessly to live in fear, and has constructed systems that embody fear. In them, staying safe is over-ridingly important. Thus we have a medical system in which most decisions are based on calculations of risk, and in which the worst possible outcome, marking the physician’s ultimate failure, is death. Yet all the while, we know that death awaits us regardless. A life saved actually means a death postponed.

The ultimate fulfillment of civilization’s program of control would be to triumph over death itself. Failing that, modern society settles for a facsimile of that triumph: denial rather than conquest. Ours is a society of death denial, from its hiding away of corpses, to its fetish for youthfulness, to its warehousing of old people in nursing homes. Even its obsession with money and property – extensions of the self, as the word “mine” indicates – expresses the delusion that the impermanent self can be made permanent through its attachments. All this is inevitable given the story-of-self that modernity offers: the separate individual in a world of Other. Surrounded by genetic, social, and economic competitors, that self must protect and dominate in order to thrive. It must do everything it can to forestall death, which (in the story of separation) is total annihilation. Biological science has even taught us that our very nature is to maximize our chances of surviving and reproducing.

I asked a friend, a medical doctor who has spent time with the Q’ero on Peru, whether the Q’ero would (if they could) intubate someone to prolong their life. “Of course not,” she said. “They would summon the shaman to help him die well.” Dying well (which isn’t necessarily the same as dying painlessly) is not much in today’s medical vocabulary. No hospital records are kept on whether patients die well. That would not be counted as a positive outcome. In the world of the separate self, death is the ultimate catastrophe.

But is it? Consider this perspectiv e from Dr. Lissa Rankin: “Not all of us would want to be in an ICU, isolated from loved ones with a machine breathing for us, at risk of dying alone- even if it means they might increase their chance of survival. Some of us might rather be held in the arms of loved ones at home, even if that means our time has come…. Remember, death is no ending. Death is going home.”

When the self is understood as relational, interdependent, even inter-existent, then it bleeds over into the other, and the other bleeds over into the self. Understanding the self as a locus of consciousness in a matrix of relationship, one no longer searches for an enemy as the key to understanding every problem, but looks instead for imbalances in relationships. The War on Death gives way to the quest to live well and fully, and we see that fear of death is actually fear of life. How much of life will we forego to stay safe?

Totalitarianism – the perfection of control – is the inevitable end product of the mythology of the separate self. What else but a threat to life, like a war, would merit total control? Thus Orwell identified perpetual war as a crucial component of the Party’s rule.

Against the backdrop of the program of control, death denial, and the separate self, the assumption that public policy should seek to minimize the number of deaths is nearly beyond question, a goal to which other values like play, freedom, etc. are subordinate. Covid-19 offers occasion to broaden that view. Yes, let us hold life sacred, more sacred than ever. Death teaches us that. Let us hold each person, young or old, sick or well, as the sacred, precious, beloved being that they are. And in the circle of our hearts, let us make room for other sacred values too. To hold life sacred is not just to live long, it is to live well and right and fully.

Like all fear, the fear around the coronavirus hints at what might lie beyond it. Anyone who has experienced the passing of someone close knows that death is a portal to love. Covid-19 has elevated death to prominence in the consciousness of a society that denies it. On the other side of the fear, we can see the love that death liberates. Let it pour forth. Let it saturate the soil of our culture and fill its aquifers so that it seeps up through the cracks of our crusted institutions, our systems, and our habits. Some of these may die too.

What world shall we live in?

How much of life do we want to sacrifice at the altar of security? If it keeps us safer, do we want to live in a world where human beings never congregate? Do we want to wear masks in public all the time? Do we want to be medically examined every time we travel, if that will save some number of lives a year? Are we willing to accept the medicalization of life in general, handing over final sovereignty over our bodies to medical authorities (as selected by political ones)? Do we want every event to be a virtual event? How much are we willing to live in fear?

Covid-19 will eventually subside, but the threat of infectious disease is permanent. Our response to it sets a course for the future. Public life, communal life, the life of shared physicality has been dwindling over several generations. Instead of shopping at stores, we get things delivered to our homes. Instead of packs of kids playing outside, we have play dates and digital adventures. Instead of the public square, we have the online forum. Do we want to continue to insulate ourselves still further from each other and the world?

It is not hard to imagine, especially if social distancing is successful, that Covid-19 persists beyond the 18 months we are being told to expect for it to run its course. It is not hard to imagine that new viruses will emerge during that time. It is not hard to imagine that emergency measures will become normal (so as to forestall the possibility of another outbreak), just as the state of emergency declared after 9/11 is still in effect today. It is not hard to imagine that (as we are being told), reinfection is possible, so that the disease will never run its course. That means that the temporary changes in our way of life may become permanent.

To reduce the risk of another pandemic, shall we choose to live in a society without hugs, handshakes, and high-fives, forever more? Shall we choose to live in a society where we no longer gather en masse? Shall the concert, the sports competition, and the festival be a thing of the past? Shall children no longer play with other children? Shall all human contact be mediated by computers and masks? No more dance classes, no more karate classes, no more conferences, no more churches? Is death reduction to be the standard by which to measure progress? Does human advancement mean separation? Is this the future?

The same question applies to the administrative tools required to control the movement of people and the flow of information. At the present writing, the entire country is moving toward lockdown. In some countries, one must print out a form from a government website in order to leave the house. It reminds me of school, where one’s location must be authorized at all times. Or of prison. Do we envision a future of electronic hall passes, a system where freedom of movement is governed by state administrators and their software at all times, permanently? Where every movement is tracked, either permitted or prohibited? And, for our protection, where information that threatens our health (as decided, again, by various authorities) is censored for our own good? In the face of an emergency, like unto a state of war, we accept such restrictions and temporarily surrender our freedoms. Similar to 9/11, Covid-19 trumps all objections.

For the first time in history, the technological means exist to realize such a vision, at least in the developed world (for example, using cellphone location data to enforce social distancing; see also here ). After a bumpy transition, we could live in a society where nearly all of life happens online: shopping, meeting, entertainment, socializing, working, even dating. Is that what we want? How many lives saved is that worth?

I am sure that many of the controls in effect today will be partially relaxed in a few months. Partially relaxed, but at the ready. As long as infectious disease remains with us, they are likely to be reimposed, again and again, in the future, or be self-imposed in the form of habits. As Deborah Tannen says, contributing to a Politico article on how coronavirus will change the world permanently, ‘We know now that touching things, being with other people and breathing the air in an enclosed space can be risky…. It could become second nature to recoil from shaking hands or touching our faces—and we may all fall heir to society-wide OCD, as none of us can stop washing our hands.” After thousands of years, millions of years, of touch, contact, and togetherness, is the pinnacle of human progress to be that we cease such activities because they are too risky?

Life is Community

The paradox of the program of control is that its progress rarely advances us any closer to its goal. Despite security systems in almost every upper middle-class home, people are no less anxious or insecure than they were a generation ago. Despite elaborate security measures, the schools are not seeing fewer mass shootings. Despite phenomenal progress in medical technology, people have if anything become less healthy over the past thirty years, as chronic disease has proliferated and life expectancy stagnated and, in the USA and Britain, started to decline.

The measures being instituted to control Covid-19, likewise, may end up causing more suffering and death than they prevent. Minimizing deaths means minimizing the deaths that we know how to predict and measure. It is impossible to measure the added deaths that might come from isolation-induced depression, for instance, or the despair caused by unemployment, or the lowered immunity and deterioration in health that chronic fear can cause. Loneliness and lack of social contact has been shown to increase inflammation , depression , and dementia . According to Lissa Rankin, M.D. , air pollution increases risk of dying by 6%, obesity by 23%, alcohol abuse by 37%, and loneliness by 45%.

Another danger that is off the ledger is the deterioration in immunity caused by excessive hygiene and distancing. It is not only social contact that is necessary for health, it is also contact with the microbial world. Generally speaking, microbes are not our enemies, they are our allies in health. A diverse gut biome, comprising bacteria, viruses, yeasts, and other organisms, is essential for a well-functioning immune system, and its diversity is maintained through contact with other people and with the world of life. Excessive hand-washing, overuse of antibiotics, aseptic cleanliness, and lack of human contact might do more harm than good . The resulting allergies and autoimmune disorders might be worse than the infectious disease they replace. Socially and biologically, health comes from community. Life does not thrive in isolation.

Seeing the world in us-versus-them terms blinds us to the reality that life and health happen in community. To take the example of infectious diseases, we fail to look beyond the evil pathogen and ask, What is the role of viruses in the microbiome ? (See also here .) What are the body conditions under which harmful viruses proliferate? Why do some people have mild symptoms and others severe ones (besides the catch-all non-explanation of “low resistance”)? What positive role might flus, colds, and other non-lethal diseases play in the maintenance of health?

War-on-germs thinking brings results akin to those of the War on Terror, War on Crime, War on Weeds, and the endless wars we fight politically and interpersonally. First, it generates endless war; second, it diverts attention from the ground conditions that breed illness, terrorism, crime, weeds, and the rest.

Despite politicians’ perennial claim that they pursue war for the sake of peace, war inevitably breeds more war. Bombing countries to kill terrorists not only ignores the ground conditions of terrorism, it exacerbates those conditions. Locking up criminals not only ignores the conditions that breed crime, it creates those conditions when it breaks up families and communities and acculturates the incarcerated to criminality. And regimes of antibiotics, vaccines, antivirals, and other medicines wreak havoc on body ecology, which is the foundation of strong immunity. Outside the body, the massive spraying campaigns sparked by Zika , Dengue Fever, and now Covid-19 will visit untold damage upon nature’s ecology. Has anyone considered what the effects on the ecosystem will be when we douse it with antiviral compounds? Such a policy (which has been implemented in various places in China and India) is only thinkable from the mindset of separation, which does not understand that viruses are integral to the web of life.

To understand the point about ground conditions, consider some mortality statistics from Italy (from its National Health Institute), based on an analysis of hundreds of Covid-19 fatalities. Of those analyzed, less than 1% were free of serious chronic health conditions. Some 75% suffered from hypertension, 35% from diabetes, 33% from cardiac ischemia, 24% from atrial fibrillation, 18% from low renal function, along with other conditions that I couldn’t decipher from the Italian report . Nearly half the deceased had three or more of these serious pathologies. Americans, beset by obesity, diabetes, and other chronic ailments, are at least as vulnerable as Italians. Should we blame the virus then (which killed few otherwise healthy people), or shall we blame underlying poor health? Here again the analogy of the taut rope applies. Millions of people in the modern world are in a precarious state of health, just waiting for something that would normally be trivial to send them over the edge. Of course, in the short term we want to save their lives; the danger is that we lose ourselves in an endless succession of short terms, fighting one infectious disease after another, and never engage the ground conditions that make people so vulnerable. That is a much harder problem, because these ground conditions will not change via fighting. There is no pathogen that causes diabetes or obesity, addiction, depression, or PTSD. Their causes are not an Other, not some virus separate from ourselves, and we its victims.

Even in diseases like Covid-19, in which we can name a pathogenic virus, matters are not so simple as a war between virus and victim. There is an alternative to the germ theory of disease that holds germs to be part of a larger process. When conditions are right, they multiply in the body, sometimes killing the host, but also, potentially, improving the conditions that accommodated them to begin with, for example by cleaning out accumulated toxic debris via mucus discharge, or (metaphorically speaking) burning them up with fever. Sometimes called “terrain theory,” it says that germs are more symptom than cause of disease. As one meme explains it: “Your fish is sick. Germ theory: isolate the fish. Terrain theory: clean the tank.”

A certain schizophrenia afflicts the modern culture of health. On the one hand, there is a burgeoning wellness movement that embraces alternative and holistic medicine. It advocates herbs, meditation, and yoga to boost immunity. It validates the emotional and spiritual dimensions of health, such as the power of attitudes and beliefs to sicken or to heal. All of this seems to have disappeared under the Covid tsunami, as society defaults to the old orthodoxy.

Case in point: California acupuncturists have been forced to shut down, having been deemed “non-essential.” This is perfectly understandable from the perspective of conventional virology. But as one acupuncturist on Facebook observed, “What about my patient who I’m working with to get off opioids for his back pain? He’s going to have to start using them again.” From the worldview of medical authority, alternative modalities, social interaction, yoga classes, supplements, and so on are frivolous when it comes to real diseases caused by real viruses. They are relegated to an etheric realm of “wellness” in the face of a crisis. The resurgence of orthodoxy under Covid-19 is so intense that anything remotely unconventional, such as intravenous vitamin C , was completely off the table in the United States until two days ago (articles still abound “debunking” the “myth” that vitamin C can help fight Covid-19). Nor have I heard the CDC evangelize the benefits of elderberry extract, medicinal mushrooms, cutting sugar intake, NAC (N-acetyl L-cysteine), astragalus, or vitamin D. These are not just mushy speculation about “wellness,” but are supported by extensive research and physiological explanations. For example, NAC ( general info , double-blind placebo-controlled study ) has been shown to radically reduce incidence and severity of symptoms in flu-like illnesses.

As the statistics I offered earlier on autoimmunity, obesity, etc. indicate, America and the modern world in general are facing a health crisis. Is the answer to do what we’ve been doing, only more thoroughly? The response so far to Covid has been to double down on the orthodoxy and sweep unconventional practices and dissenting viewpoints aside. Another response would be to widen our lens and examine the entire system, including who pays for it, how access is granted, and how research is funded, but also expanding out to include marginal fields like herbal medicine, functional medicine, and energy medicine. Perhaps we can take this opportunity to reevaluate prevailing theories of illness, health, and the body. Yes, let’s protect the sickened fish as best we can right now, but maybe next time we won’t have to isolate and drug so many fish, if we can clean the tank.

I’m not telling you to run out right now and buy NAC or any other supplement, nor that we as a society should abruptly shift our response, cease social distancing immediately, and start taking supplements instead. But we can use the break in normal, this pause at a crossroads, to consciously choose what path we shall follow moving forward: what kind of healthcare system, what paradigm of health, what kind of society. This reevaluation is already happening, as ideas like universal free healthcare in the USA gain new momentum. And that path leads to forks as well. What kind of healthcare will be universalized? Will it be merely available to all, or mandatory for all – each citizen a patient, perhaps with an invisible ink barcode tattoo certifying one is up to date on all compulsory vaccines and check-ups. Then you can go to school, board a plane, or enter a restaurant. This is one path to the future that is available to us.

Another option is available now too. Instead of doubling down on control, we could finally embrace the holistic paradigms and practices that have been waiting on the margins, waiting for the center to dissolve so that, in our humbled state, we can bring them into the center and build a new system around them.

There is an alternative to the paradise of perfect control that our civilization has so long pursued, and that recedes as fast as our progress, like a mirage on the horizon. Yes, we can proceed as before down the path toward greater insulation, isolation, domination, and separation. We can normalize heightened levels of separation and control, believe that they are necessary to keep us safe, and accept a world in which we are afraid to be near each other. Or we can take advantage of this pause, this break in normal, to turn onto a path of reunion, of holism, of the restoring of lost connections, of the repair of community and the rejoining of the web of life.

Do we double down on protecting the separate self, or do we accept the invitation into a world where all of us are in this together? It isn’t just in medicine we encounter this question: it visits us politically, economically, and in our personal lives as well. Take for example the issue of hoarding, which embodies the idea, “There won’t be enough for everyone, so I am going to make sure there is enough for me.” Another response might be, “Some don’t have enough, so I will share what I have with them.” Are we to be survivalists or helpers? What is life for?

On a larger scale, people are asking questions that have until now lurked on activist margins. What should we do about the homeless? What should we do about the people in prisons? In Third World slums? What should we do about the unemployed? What about all the hotel maids, the Uber drivers, the plumbers and janitors and bus drivers and cashiers who cannot work from home? And so now, finally, ideas like student debt relief and universal basic income are blossoming. “How do we protect those susceptible to Covid?” invites us into “How do we care for vulnerable people in general?”

That is the impulse that stirs in us, regardless of the superficialities of our opinions about Covid’s severity, origin, or best policy to address it. It is saying, let’s get serious about taking care of each other. Let’s remember how precious we all are and how precious life is. Let’s take inventory of our civilization, strip it down to its studs, and see if we can build one more beautiful.

As Covid stirs our compassion, more and more of us realize that we don’t want to go back to a normal so sorely lacking it. We have the opportunity now to forge a new, more compassionate normal.

Hopeful signs abound that this is happening. The United States government, which has long seemed the captive of heartless corporate interests, has unleashed hundreds of billions of dollars in direct payments to families. Donald Trump, not known as a paragon of compassion, has put a moratorium on foreclosures and evictions. Certainly one can take a cynical view of both these developments; nonetheless, they embody the principle of caring for the vulnerable.

From all over the world we hear stories of solidarity and healing. One friend described sending $100 each to ten strangers who were in dire need. My son, who until a few days ago worked at Dunkin’ Donuts, said people were tipping at five times the normal rate – and these are working class people, many of them Hispanic truck drivers, who are economically insecure themselves. Doctors, nurses, and “essential workers” in other professions risk their lives to serve the public. Here are some more examples of the love and kindness eruption, courtesy of ServiceSpace :

Perhaps we’re in the middle of living into that new story. Imagine Italian airforce using Pavoratti, Spanish military doing acts of service, and street police playing guitars — to *inspire*. Corporations giving unexpected wage hikes. Canadians starting “Kindness Mongering.” Six year old in Australia adorably gifting her tooth fairy money, an 8th grader in Japan making 612 masks , and college kids everywhere buying groceries for elders. Cuba sending an army in “ white robes ” (doctors) to help Italy. A landlord allowing tenants to stay without rent, an Irish priest’s poem going viral, disabled activitists producing hand sanitizer. Imagine. Sometimes a crisis mirrors our deepest impulse — that we can always respond with compassion.

As Rebecca Solnit describes in her marvelous book, A Paradise Built in Hell , disaster often liberates solidarity. A more beautiful world shimmers just beneath the surface, bobbing up whenever the systems that hold it underwater loosen their grip.

For a long time we, as a collective, have stood helpless in the face of an ever-sickening society. Whether it is declining health, decaying infrastructure, depression, suicide, addiction, ecological degradation, or concentration of wealth, the symptoms of civilizational malaise in the developed world are plain to see, but we have been stuck in the systems and patterns that cause them. Now, Covid has gifted us a reset.

A million forking paths lie before us. Universal basic income could mean an end to economic insecurity and the flowering of creativity as millions are freed from the work that Covid has shown us is less necessary than we thought. Or it could mean, with the decimation of small businesses, dependency on the state for a stipend that comes with strict conditions. The crisis could usher in totalitarianism or solidarity; medical martial law or a holistic renaissance; greater fear of the microbial world, or greater resiliency in participation in it; permanent norms of social distancing, or a renewed desire to come together.

What can guide us, as individuals and as a society, as we walk the garden of forking paths? At each junction, we can be aware of what we follow: fear or love, self-preservation or generosity. Shall we live in fear and build a society based on it? Shall we live to preserve our separate selves? Shall we use the crisis as a weapon against our political enemies? These are not all-or-nothing questions, all fear or all love. It is that a next step into love lies before us. It feels daring, but not reckless. It treasures life, while accepting death. And it trusts that with each step, the next will become visible.

Please don’t think that choosing love over fear can be accomplished solely through an act of will, and that fear too can be conquered like a virus. The virus we face here is fear, whether it is fear of Covid-19, or fear of the totalitarian response to it, and this virus too has its terrain. Fear, along with addiction, depression, and a host of physical ills, flourishes in a terrain of separation and trauma: inherited trauma, childhood trauma, violence, war, abuse, neglect, shame, punishment, poverty, and the muted, normalized trauma that affects nearly everyone who lives in a monetized economy, undergoes modern schooling, or lives without community or connection to place. This terrain can be changed , by trauma healing on a personal level, by systemic change toward a more compassionate society, and by transforming the basic narrative of separation: the separate self in a world of other, me separate from you, humanity separate from nature. To be alone is a primal fear, and modern society has rendered us more and more alone. But the time of Reunion is here. Every act of compassion, kindness, courage, or generosity heals us from the story of separation, because it assures both actor and witness that we are in this together.

I will conclude by invoking one more dimension of the relationship between humans and viruses. Viruses are integral to evolution, not just of humans but of all eukaryotes. Viruses can transfer DNA from organism to organism, sometimes inserting it into the germline (where it becomes heritable). Known as horizontal gene transfer, this is a primary mechanism of evolution, allowing life to evolve together much faster than is possible through random mutation. As Lynn Margulis once put it, we are our viruses.

And now let me venture into speculative territory. Perhaps the great diseases of civilization have quickened our biological and cultural evolution, bestowing key genetic information and offering both individual and collective initiation. Could the current pandemic be just that? Novel RNA codes are spreading from human to human, imbuing us with new genetic information; at the same time, we are receiving other, esoteric, “codes” that ride the back of the biological ones, disrupting our narratives and systems in the same way that an illness disrupts bodily physiology. The phenomenon follows the template of initiation: separation from normality, followed by a dilemma, breakdown, or ordeal, followed (if it is to be complete) by reintegration and celebration.

Now the question arises: Initiation into what? What is the specific nature and purpose of this initiation?The popular name for the pandemic offers a clue: coronavirus. A corona is a crown. “Novel coronavirus pandemic” means “a new coronation for all.”

Already we can feel the power of who we might become. A true sovereign does not run in fear from life or from death. A true sovereign does not dominate and conquer (that is a shadow archetype, the Tyrant). The true sovereign serves the people, serves life, and respects the sovereignty of all people. The coronation marks the emergence of the unconscious into consciousness, the crystallization of chaos into order, the transcendence of compulsion into choice. We become the rulers of that which had ruled us. The New World Order that the conspiracy theorists fear is a shadow of the glorious possibility available to sovereign beings. No longer the vassals of fear, we can bring order to the kingdom and build an intentional society on the love already shining through the cracks of the world of separation.

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The Role of the Olive in Human History and Lives Essay

• To find inspiration for your paper and overcome writer’s block
• As a source of information (ensure proper referencing)
• As a template for you assignment

Introduction

Works cited.

Olea europaea is widely known as the olive and was originally found in the Mediterranean Basin. It is a subtropical evergreen tree commonly acknowledged as one of the oldest cultivated trees (Kiritsakis and Shahidi 1). “The olive is often considered the most iconic tree of the Mediterranean world” (Besnard and Rubio de Casas 466). Olive fruit and its by-products, such as olive oil, are essential ingredients of Mediterranean cuisine and have become popular worldwide. According to Foscolou et al., this crop is also prized for its great benefits for human health and some chronic diseases (60). Therefore, the cultivation and consumption of olives had a strong impact on the Mediterranean culture and was a deciding factor for the history of numerous cuisines and world medicine.

First of all, to estimate the value of the olive tree more precisely, it is necessary to investigate the history of the olive. Certainly, defining the origin time of the crop right is not possible. The period of wild olive domestication is not known exactly, either. Nevertheless, many experts often state that olives have been first cultivated in about 3000 BC around the eastern Mediterranean coast (Torres et al. 2). It has subsequently spread all over the Mediterranean Basin, Europe, and Africa in particular. Then the common interest in olive oil and the necessity of its production have extended olive cultivation to distant regions, including China, Australia, and South America. In terms of botany, there is also a considerable evolution of varieties of olive trees. “During the evolutionary course of the olive tree, more than 1500 olive cultivars were created by man, making its expansion possible” (Kiritsakis and Shahidi 3). Therefore, the initial cultivation of the olive and its following transformation has made it one of the most important and valuable cultures in history.

Moreover, the olive has deeply influenced the culture of the Mediterranean region. First of all, plenty of ancient Greek legends and mythology stories are tightly connected with olive. The origin of the olive tree is described in Greek mythology: “According to the legend, the olive tree was a gift from the gods to the ancient Greeks.” (Kiritsakis and Shahidi 1). Consequently, it can be traced through history how much importance the Greeks attached to olive. The widely famous Olympic crowning wreath was made of a branch of wild olive (Kiritsakis and Shahidi 2). The ancient winners of the Olympic games also received a cup filled with olive oil. Greek athletes even covered their bodies with olive oil before a competition to warm the muscles and protect the skin from the sun. At the same time, olive oil has been regarded as holy and sacred in many other cultures and is still used in different religious ceremonies. Thereby, the olive tree was a great part of national culture in ancient times and plays a key role in the traditions and religions of different countries nowadays.

At present, olive trees and olive oil are appreciated as highly as in the past. The production of olive oil and olive cultivation is spread now, even in countries with no olive trees grown before. The crop is grown commercially in over 30 countries, such as Spain, Italy, Turkey, Greece, and the United States. Olive became cultivated even in China, whose climate is completely different from the Mediterranean (Su et al. 1). Additionally, some specialists claim that current ecological, political, and economic changes had never been so crucial for the future of the olive tree (Besnard et al. 398). In particular, these changes concern the olive’s native land, the Mediterranean coast. They are sometimes expected to transform the previous area of olive growth notably. However, the countries of the Mediterranean Basin are still the most powerful olive producers considering the amount of oil and number of trees (Kiritsakis and Shahidi 1). Thus, the importance of olive cultivation, investigation of its nature, and further domestication of the olive are as significant as ever because olive by-products are highly demanded in today’s market.

In its turn, the wide use of the olive can be considered another noticeable sign of high olive value in different corners of the earth. In ancient times olive oil was popular for numerous varieties of activities and served different vital needs. For example, “In antiquity, olive oil was used for cooking, lighting, as well as for cultic and medical purposes” (Langgut et al. 1). The olive was one of the essential natural resources that provided edible fruits and multifunctional oil. Furthermore, the olive tree was widely used as a wood source and often as fodder (Besnard and Rubio de Casas 466). In this way, people produced something from the olive and found many practical applications of the olive tree in the rough. It is known that olive oil has a religious meaning and significance. In accordance with historical facts, it served as a body ointment during rituals and was used by saints to cure diseases (Besnard and Rubio de Casas 466). As a result, the olive tree and its oil had great practical and spiritual importance for the ancient people of the Mediterranean world.

Nowadays, the usage of the olive and its by-product is as widespread as previously. Olive oil is commonly used for cooking, frying, salad dressing, medicine, and cosmetics. There are many kinds of olive oil for different purposes, such as virgin or refined olive oil and olive-pomace oil (Capogna and Gómez 4). As the cultivation of this crop had spread all over the planet, the consumption of olive oil and olive fruits increased too. For instance, Japan is now one of the biggest Asian consumers of olive oil, and the olive makes an integral part of the whole Japanese market (Capogna and Gómez 1). Besides, olive oil is still widely used for cultic purposes in different religions. Olive branches retained their symbolic meaning of peace, victory, and friendship. At the same time, olive wood is used for furniture, tools, decorative items, and other production. In consequence, while the olive was gaining high popularity, people worldwide became interested in its beneficial usage for various aims. Just like that, olive import and export formed an essential part of business and the global market.

One of the other significant reasons for the high olive value that has endured for so long is that olive oil has been widely used in medicine for many centuries. This fact is connected with the observation of the benefits and positive influence of olives on human health. Scientists discovered that the olive, being “the foremost source of fat in the Mediterranean area” (Visioli et al. 4), leads to reducing the risk of different diseases and improves human health in general. The continuous consumption of olive oil is usually stated now to be the reason for “longevity and lower incidence of coronary heart disease, cancer, and neurodegeneration” (Visioli et al. 4). Olive oil contains fatty acids that seem to decrease cholesterol levels, fight inflammation, and lower blood pressure. Therefore, olive leaf and olive oil can become a big part of a healthy lifestyle and prevent various diseases.

Furthermore, for the reasons stated above, olive oil is used in medicine in many different ways. Olive oil may serve as an anti-inflammatory and an antibacterial. It is proven that olive oil can prevent or even treat infection or inflammation. It can also be used as a prevention of cancer, particularly breast cancer and heart disease, as it is full of useful antioxidants (Foscolou et al. 63). Thus, by consuming a daily spoonful of olive oil, people can get lots of benefits for their health and protect themselves from several diseases. In addition, olive oil is used in cosmetics, as it is very beneficial for our skin. Its antioxidants and vitamins have anti-aging effects and relieve sun damage. It is a good ingredient for lotions and soaps because it effectively serves as a deep moisturizer and cleanser. Due to its numerous effects on human health and the human body, olive oil is widely applied in different areas of medicine and cosmetology.

Nevertheless, olive oil has some side effects, which should be considered during the consumption of olive or applying olive oil on the skin. Although olive seems to be quite safe, it should be used as no more than 14% of total daily calories. In a Mediterranean-style diet, olive oil has been used safely for a long time in the quantity of about one liter per week. Besides, olive oil is reported to cause nausea and allergy on rare occasions. “The pollen from the olive leaf can trigger severe respiratory allergic reactions in people who are allergic to plants in the Oleaceae family” (Wong). Lastly, there are several special warnings and precautions for some categories of people. For instance, olive oil might lower blood sugar, and people with diabetes should always check it before using olive oil. For the same reason, olive oil should not be consumed before surgery, as it can affect blood sugar control. Summing up, despite all the use of olive oil, people should remember the side effects. Even though they might seem to be not so dangerous, they might noticeably affect human health.

In conclusion, it is important to underline that the great role of the olive in human history and lives cannot be underestimated. Olive oil and the olive tree are known from ancient times when they were described in historical manuscripts and used as a ritual instruments and for practical purposes. With the cultivation of the olive, its fruit and oil became popular ingredients in the cuisines of various nations. Over time, the great influence of olive oil on human health became known worldwide as well. Therefore, people started to use it for different medical purposes, cosmetics, decoration, and furniture production. Finally, as the olive has always had a religious and symbolic meaning, it visibly influenced the culture and history of the ancient Greeks and other nations.

Besnard, Guillaume, and Rafael Rubio de Casas. “Single vs Multiple Independent Olive Domestications: The Jury is (still) out.” New Phytologist , vol. 209, no. 2, 2016, pp. 466-470.

—, et al. “On the Origins and Domestication of the Olive: a Review and Perspectives.” Annals of Botany , vol. 121, no. 3, 2018, pp. 385-403.

Capogna, Daniela, and María Isabel Gómez. “Olive Oil: An Overview of the Japanese Market.” OCL , vol. 23, no. 6, 2016, pp. 1-5.

Foscolou, Alexandra, et al. “Olive Oil Consumption and Human Health: A Narrative Review.” Maturitas , vol. 118, 2018, pp. 60-66.

Kiritsakis, Apostolos, and Fereidoon Shahidi, editors. Olives and Olive Oil as Functional Foods: Bioactivity, Chemistry and Processing . John Wiley & Sons, 2017.

Langgut, Dafna, et al. “The Origin and Spread of Olive Cultivation in the Mediterranean Basin: The Fossil Pollen Evidence.” The Holocene , vol. 29, no. 5, 2019, pp. 902-922.

Su, ChunJiang, et al. “History, Distribution, and Potential of the Olive Industry in China: A Review.” Sustainability , vol. 10, no. 5, 2018, pp. 1-19.

Torres, Mariela, et al. “Olive Cultivation in the Southern Hemisphere: Flowering, Water Requirements and Oil Quality Responses to New Crop Environments.” Frontiers in Plant Science, vol. 8, 2017, pp. 1-12.

Visioli, F., et al. “Olive Oil and Prevention of Chronic Diseases: Summary of an International Conference.” Nutrition, Metabolism and Cardiovascular Diseases , vol. 28, no. 7, 2018, pp. 649-656.

Wong, Cathy. “What is Olive Leaf Extract?” Verywellhealth.

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Bibliography

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The Life Cycle of an Olive Tree: Detailed Explanation

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Have you ever wondered how olive trees grow or how long they live? In this article, we will be looking at the life cycle of an olive tree, which is important to understand if you want to grow these wonderful plants.

Key Takeaways:

• Olive trees, one of the first trees cultivated by humans, can live for hundreds of years.
• Germination from seeds requires fresh olives; seeds take weeks to germinate and are transplanted in autumn.
• Seedlings grow slowly and need shade and frequent watering, especially in pots.
• Trees grow about 12 inches per year, taking years to reach notable size; some are ornamental.
• Annually, trees develop buds in spring, leading to flowering and fruiting by summer’s end.
• Olive trees can live between 300 to 500 years, with some believed to be 1500 years old.

The Life Cycle of an Olive Tree

Olive trees are believed to have been among the first trees to be cultivated by man. A sturdy, attractive tree that produces the fruit we love, the olive tree can live for hundreds of years. While slow growing, they are relatively simple to grow, hence their popularity.

In this section, we will talk about the life cycle of the olive tree from germination to maturity.

Germination

Olive trees are more often than not grown from cuttings ( see our informative article here .) This is the easiest method. However, we want to look at growing from seeds, otherwise known as ‘pits.’ These are the hard seed matter within the olive.

Related: How Long To Grow Olive Tree From Seed

Our first key point is that you will not succeed in germinating an olive plant if you use fruit bought from the store. It must be fresh and from the tree to be fertile. Pick fruit that is in good condition and ripe, preferably not from the ground.

The expert method involves soaking the fresh olives in water overnight, then breaking the olives and removing the pits. It is recommended that you take a pinch out of the end of the pits for more chance of success and then soak the seed in water for another night.

Olive pits should then be sown. These are plants that grow in the Mediterranean climate and prefer a mix of sand and seed compost. We recommend you sow several seeds, as success is not guaranteed!

Put them in the soil – not too deep – and keep them in the shade with the top moist. Bear in mind that olives take a while to germinate. You may see signs within a few weeks, but it can take up to six weeks or more. Once you have seedlings, keep them as they are and look to transplant them in the autumn.

That’s your first stage – germination – complete, and it can be frustrating when you go to the trouble of preparing pits for growth, and nothing happens. Do persevere, for there will be one at least that springs into life.

Olive tree seedlings do need some care. Depending upon where you are in the world, you may find that a heat mat and a cold frame are of great help. Keep the seedlings out of the hot summer sun – they will thrive when they mature but may not when in their infancy – and in a shady area.

Seedlings grow slowly. The olive tree doesn’t race into life but approaches it gradually. Seedlings are best grown and cared for in pots or other containers. Many people keep their olive trees pot-bound, but they do grow best to maturity in the ground.

Water your pots when the soil gets dry, and make sure it is thoroughly soaked. Olive trees in pots will need to be watered more often than those in the ground.

Now you have germinated olive pits successfully and are caring for seedlings, we need to look at the vegetative growth stage that follows.

Vegetative Growth

You will see the growth of the olive tree you have propagated as you follow its progress. If you leave your tree in the pot, it will grow more slowly than in the ground. Don’t expect your seedlings to become fully-fledged trees quickly.

It can take a few years for notable growth to be seen. As we have said, these are slow-growing and long-lived trees. Be aware that some olive trees are ‘fruitless.’ These are grown as ornamental trees rather than for harvesting.

You will note two different types of growth: flower buds and vegetative growth. The latter is the formation of new leaves. Both are part of the phenological process, as we shall see later on.

To continue our look at the olive tree’s life, let’s assume you have a tree that is close to maturity. What should you expect?

The olive tree remains relatively dormant during the colder months . Come the warmer days of spring, and you’ll begin to see your trees sprouting buds. The olive flower follows the tree in being slow to open, but when it does, it is a delightful sight.

Floral clusters will open across the tree, and it is at this point that the fruiting process begins. You will see a difference in flowers and fruit year to year. This is because varied weather conditions influence how many flowers the tree produces.

Once the flowers are done, the petals naturally fall to the ground – and there you will see your olives! Olives continue to grow in size and usually reach maturity in the autumn months.

It is traditional to pick olives when they are still green – it’s often forgotten that green and black olives are the same fruit, with the black variety having ripened fully – and to pick them directly from the tree.

So, you now have a mature and fruiting olive tree – what else do you need to know? We’ll be looking in more detail at the growth stages of the mature tree in a moment, but before we move on, here’s a quick look at what to expect from your mature olive trees.

When does an olive tree reach maturity? An olive tree will grow at the rate of around 12 inches every year. The tree remains a juvenile until it is perhaps 15 years old or even more. As mentioned, this is a long-lived tree.

A fully mature olive tree can reach 15 meters tall – around 50 feet – and is a broad, attractive tree that is instantly recognizable. Your olive trees may need pruning – our article on this detail explains more – if you want to keep them in good shape, but apart from that, maintaining olive trees is not difficult once they reach maturity.

Now we want to get a little more scientific and talk about what is known in the growing industry as the ‘phenological phases’ of olive tree growth. We have covered this area above, but we feel it may be interesting to recap and maybe expand a little.

Olive Phenological Phases

Phenology is the study of cycles in the natural world. In this case, we are interested in the phenological stages of the olive fruit. We’ve described the beginnings of the tree up until maturity, so we need to look at the annual cycle of fruiting. Let’s get started!

Bud Development

The annual phenological cycle of the olive begins in the spring – March and April in its natural habitat – with the sprouting stage. This can be observed by looking for buds that form around this time. These will initially be seen as green growth and are the beginning of the reproductive process of the tree, which results in the fruit.

Leaf Development

The buds will form into either flower clusters or leaves. Leaf development – vegetative growth – will be noted in the form of regular olive tree leaves sprouting from the branches.

Appearance of Flowers

The first appearance of flowers on the olive tree will occur at the same time as the leaves develop. Buds that do not become leaves will form flower clusters. This is the continuation of the reproduction stage of the tree, which will eventually become the olive fruit. Flowering is the next stage.

Your olive trees will become adorned with many flowers as the buds open. At this point, the flowers need to be fertilized. Only fertilized flowers can become fruit.

Flowering will begin in May . A flower cluster will last only a week, and the entire flowering process will last three weeks or more.

What is interesting at this point is that very few of the flowers will bear fruit. Olive trees are generally self-pollinating, although it is not unusual for growers to plant flowers and other plants to attract pollinators .

This is important as the more fertilized flowers, the more fruit will be borne by the tree. In fact, it is estimated that a mere 2% of maximum flowers will bear fruit , and this is why olive trees produce many flower clusters.

Fruit Development

Once the flowering period is over, you will begin to see the new olive fruit in its place. This is an interesting phase in the phenology of the olive. This will occur during July and August when it is notably hot and dry.

There is a phase known as ‘fruit set.’ This is where the olive tree releases some of the young olives to fall from the tree. The stronger fruit remain and are able to feed and grow.

The stage of fruit development is the most fascinating and is a wonder of nature. The olive tree deals with the heat and lack of water by closing what is known as ‘stomata’ – tiny pores on the leaves that allow for evaporation – thus preserving the water within to help feed the fruit.

The olives grow until a certain size, at which point they are often picked when still green.

Fruit Ripening

Green olives are those that have been picked for use before they are fully ripe. Left on the tree, the olives will turn yellow or pink before reaching the deep red or black coloring of ripe and mature olives.

The phenological phases are done, and the olive tree now waits until next spring to begin again.

The average lifespan of an olive tree is between 300 to 500 years! There are trees that are believed to be 1500 years old, but it is difficult to clarify.

Grown from seed, successful germination will become a mature tree at around 12 to 15 years old. Juvenile trees will add 12 inches each year. As for the fruit, from the shooting stage in spring until the fruits become large enough to harvest and begin to ripen will take around three to four months.

This is a long-lived species. There are instances in which olive trees have lived for 1000 years. Indeed, the oldest tree still living is believed to be 1500 years old.

My journey with olives began in 2014, when I moved to Dubrovnik - a beautiful Mediterranean city. Immersing myself in the local culture, I forged deep connections with seasoned olive oil craftsmen, absorbing their invaluable expertise. Now, as a cultivator and an informed voice in this field, I share these rich insights and the legacy of olive oil on this website.

The Olive Tree: Understanding Where Olives Grow

Olives, the small, oval-shaped fruits we often associate with Mediterranean cuisine, are actually grown in various parts of the world. These fruits, which are actually classified as drupes, are a staple in many diets and are also used to produce olive oil, a key ingredient in many dishes. But where exactly do olives grow? Let’s delve into the world of olive cultivation and understand the regions that favor olive growth.

Table of Contents

The Natural Habitat of Olive Trees

Olive trees (Olea europaea) are native to the Mediterranean region, which includes parts of Europe, Africa, and Asia. This region, characterized by its hot, dry summers and mild, rainy winters, provides the ideal conditions for olive trees to thrive. The trees are hardy and can withstand the harsh Mediterranean climate, making them a popular choice for farmers in these regions.

According to the United Nations Food and Agriculture Organization (FAO), the Mediterranean region accounts for over 95% of the world’s olive production. Countries like Spain, Italy, and Greece are the top producers, with Spain alone accounting for about 45% of the global olive oil production.

Spain: The Olive Capital of the World

Spain’s Andalusia region is often referred to as the ‘olive capital of the world’. The region’s climate, characterized by hot summers and mild winters, along with its fertile soil, makes it an ideal location for olive cultivation. The region is home to over 150 million olive trees, covering an area of approximately 1.5 million hectares.

Andalusia produces a variety of olive types, including the popular Picual, Hojiblanca, and Manzanilla varieties. These olives are used both for table consumption and for the production of olive oil.

Italy and Greece: Centuries-Old Olive Cultivation

Italy and Greece, two other major olive-producing countries, have a long history of olive cultivation. In Italy, regions like Tuscany, Puglia, and Calabria are known for their olive groves. The country produces a variety of olives, including the Frantoio, Leccino, and Coratina varieties.

Greece, on the other hand, is known for its Kalamata olives, named after the city of Kalamata in the Peloponnese region. The country’s climate, with its mild winters and hot, dry summers, is ideal for olive cultivation.

Olive Cultivation Beyond the Mediterranean

While the Mediterranean region is the primary producer of olives, the cultivation of olive trees has spread to other parts of the world. Countries like the United States, Argentina, Australia, and South Africa have also started growing olives, thanks to their suitable climates.

The United States, for instance, has seen a significant increase in olive production in recent years. California, in particular, has become a major producer, with its climate closely resembling that of the Mediterranean region. Other states like Texas, Arizona, and Florida have also started growing olives.

Australia: A New Player in the Olive Industry

Australia has emerged as a new player in the olive industry. The country’s climate, particularly in regions like South Australia and Western Australia, is suitable for olive cultivation. Australian olive oil is gaining recognition for its quality and unique flavor profiles.

Similarly, Argentina and South Africa have also started cultivating olives. These countries, with their Mediterranean-like climates, are well-suited for olive production. They primarily grow olives for oil production, although table olives are also produced.

Understanding the Olive Growing Process

Now that we know where olives grow, let’s take a look at how they are cultivated. The process of growing olives can be broken down into several steps:

• Choosing the Right Variety: The first step in growing olives is choosing the right variety. Different olive varieties are suited to different climates and soil types, so it’s important to choose a variety that’s suitable for your region.
• Planting the Trees: Once you’ve chosen the right variety, the next step is to plant the trees. Olive trees can be grown from seeds, cuttings, or young trees. They should be planted in well-drained soil, in a location that receives plenty of sunlight.
• Pruning and Fertilizing: Olive trees need to be pruned regularly to maintain their shape and promote fruit production. They also need to be fertilized annually to ensure they receive the necessary nutrients.
• Harvesting the Olives: Olives are typically harvested in the fall, when they are ripe. The olives can be hand-picked or harvested using mechanical shakers.
• Processing the Olives: After harvesting, the olives are processed to remove any leaves or stems. They are then washed and either pressed for oil or cured for table consumption.

Olives are a versatile fruit that are grown in various parts of the world. While the Mediterranean region is the primary producer of olives, countries like the United States, Australia, Argentina, and South Africa have also started growing olives, thanks to their suitable climates. Whether you’re enjoying a bowl of olives or using olive oil in your cooking, remember the journey these fruits have taken from the tree to your table.

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Home > Books > Olive Cultivation

The Olive Tree: A Symbol

Submitted: 01 November 2021 Reviewed: 23 January 2022 Published: 28 March 2022

DOI: 10.5772/intechopen.102827

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The olive tree is not only the typical plant of the Mediterranean but it is also a tree that constitutes the only culture of global importance. From very old times through the centuries, the traditions of the great oil-growing areas of today were born and consolidated—Greece, Italy, and Spain. The olive tree and oil are an indispensable presence for our daily well-being, as well as a reminder of our oldest and truest history. Olive tree became a symbol of peace and value, an element of strength and purification, of resistance to the ravages of time and wars, the olive tree has always been a transcendent symbol of spirituality and sacredness.

• multifunctionality
• symbol of peace and valor
• spirituality and sacredness
• significant role in religion

Author Information

Stefano grego *.

• Interuniversity Centre for Research on Sustainable Development (CIRPS), Rome, Italy

*Address all correspondence to: [email protected]

1. Introduction

No other tree or plant, with the exception of wheat, has had the same importance in the history of our species as the olive, capable of influencing nutrition, culture, and religion and contributing to the birth of modern Mediterranean civilization [ 1 ]. The unmistakable gnarled and curved branches of olive trees have shaped the Mediterranean landscape and their fruits have provided sustenance to numerous civilizations, from the Middle East to Greece, from Italy to Spain. “Two are the liquids particularly pleasing to the human body: inside the wine, outside the oil,” wrote Pliny the Elder in his famous treatise Natural History. “Oil is an absolute necessity and man was not wrong in dedicating his efforts to obtain it.”

2. A short history

To understand when the olive tree became essential for the peoples of the Mediterranean, it is necessary to take a journey into the past, going back thousands of years, trying to understand the origins of this special plant. It is believed that the first cultivation of olive trees, as we know them today, began about six to seven thousand years ago in the regions of the Middle East, in an area corresponding to ancient Persia and Mesopotamia. Here, the wild olive tree was domesticated and the oil was produced for the first time. From the Bronze Age, this precious substance spread like wildfire, thanks to merchants, moving between Syria, Lebanon, Israel, Palestine, Egypt, Greece, and Italy, and over time it acquired a growing socio-economic value. Terral et al. [ 2 ] analyzed the genetic differences between wild and cultivated olive trees, to trace the origin of the modern European olive tree, the European Olea [ 3 ]. According to the scholar, the birth of the modern olive tree is more complex than one might think, deriving as it does from the crossing of 11 different varieties. One thing is certain, however, the olive tree has been part of the Mediterranean flora since time immemorial, fossil pollen of the genus Olea has in fact been found in several Mediterranean countries, such as Macedonia and Greece, while fossilized leaves dating back to about 37 thousand years ago have been found on the Greek island of Santorini ( Figure 1 ) [ 4 ].

Olive Grove in Santorini.

In 2500 BC within the Babylonian code of Hammurabi, the production and trade of olive oil were regulated, while around 1300 BC olive branches embellished the tombs of the pharaohs.

Thanks to the Greeks, the olive tree spread around the Mediterranean. It was considered very important in Greek culture and is mentioned in Greek mythology, “Poseidon, god of the sea, and Athena, daughter of Zeus, goddess of wisdom”, competed to win possession of protection over Athens [ 5 ]. Poseidon hit the rock with his trident (on which the Acropolis would later rise) and from this, he made a source of seawater come out and a horse faster than the wind. Athena planted the first olive tree, a tree that, for millennia, with its fruits would give a wonderful juice that men could use for the preparation of food, for the care of the body, for the healing of wounds and diseases, and as a source of light for homes ( Figure 2 ).

Poseidon and Athena.

Thucydides (fifth century BC) wrote that “The peoples of the Mediterranean began to emerge from barbarism when they learned to cultivate olive trees and vines.”

After the Greeks who favored the spread of the olive tree in the Mediterranean, the Romans took on the task of bringing the cultivation of this plant to greater development. The olive tree was planted everywhere in the empire, so much so that the Roman Empire imposed the payment of taxes in the form of olive oil. Also thanks to them the production process improved, there was a distinction made between different types of oil connected to the moment of pressing, (5 species of oil were identified). Even in Roman mythology, oil had a certain importance in fact it was Hercules who introduced the olive tree from North Africa and then the goddess Minerva would have taught men the art of cultivation and extraction of oil. As usual, with the fall of the Roman Empire, olive cultivation also experienced a period of decline,

The olive tree played an important role in various fields, including in sport—Greek athletes anointed themselves with olive oil before fighting and the winners of the Olympics were crowned with sacred olive branches and rewarded with richly decorated oil ampoules. Both the Greeks and the Romans used olive oil in the preparation of numerous recipes; moreover, it was widely used for therapeutic, medicinal, balsamic, and detergent purposes or as a fuel for votive lamps ( Figure 3 ).

Symbolic wreath of olive branches.

With the advent of the dominion of Rome, the olive tree had one of its greatest moments of glory and extended its range to reach areas in which until that moment, also due to the unfavorable climate, its cultivation had been marginal or nonexistent. The context in which the Berber populations of northern Africa learned the art of grafting olive trees is not known, but we know from Latin sources that they already practiced it when the Romans conquered their lands.

Finally, in the New World, olive trees were introduced soon after their discovery at the end of the fifteenth century. The first olive trees arrived in the Antilles from the port of Seville after the discovery of the New World and since 1560 olive groves have been observed in Mexico and later also in Peru, California, Chile and Argentina [ 6 ].

3. The olive and the monotheistic religions

The presence of the olive tree as a symbol and in myths goes back a long way and has its roots in prehistory. Over time, these plants have lent themselves to numerous interpretations—for Homer, the olive tree was a symbol of peace and life. The Greek poet also included it in the Odyssey—it was in fact an olive tree trunk, a plant sacred to Athena, the one with which Ulysses blinded the Cyclops Polyphemus. It was also considered an emblem of strength and victory, in ancient Greece, the winners of the Olympics were offered a wreath of olive trees and a cruet of oil. The deep bond between the Hellenic country and the olive tree is certified by the legend according to which the goddess Athena struck the rock with her spear, giving birth to the first olive tree in the world. Even in ancient Rome, olive oil, an indispensable product in daily life and an ingredient of Roman cuisine, and the plant from which the precious fruits were born were revered. The myth has it that Romulus and Remus, the twin protagonists of the Roman mythological tradition, were born right under an olive tree. The ancient Egyptians believed instead that it was the goddess Isis who revealed the properties of the olive tree to man and taught him the art of cultivating and producing oil.

The Olive tree is so strongly associated with peace, rebirth, and victory, that it is hardly surprising that it has become one of the main symbols of Easter, a sign of rebirth and regeneration [ 7 ].

According to the scriptures, it was after the Great Flood that Noah received an olive branch from a dove, which from that moment became the symbol of the promise of rebirth, of a new beginning, and of regeneration [ 8 ].

The history of the Olive tree is lost, intertwined, in the history of humanity. All we can get from the symbolism of this tree are some Greek/Roman customs and practices that attest to its importance also for polytheistic religions.

For example, in Greece, the olive tree was considered a sacred tree, to the point that anyone caught damaging or cutting it was exiled. At the Olympics, an olive crown was given to the winner, along with an oil cruet. But not only—in Athens, a particular olive tree was recognized as the first olive tree in the world, which was, therefore, treated with great respect and considered sacred, as connected to the goddess Athena, Patroness of the city.

The custom of crowning with an olive tree was not lost and it seems was also imported to Rome, where this particular crown was used to honor the most valiant citizens, against the more famous laurel wreath which was instead taken as a symbol of victory and domain.

More likely, however, the Catholic symbolism of the Olive tree derives from a synthesis of these pagan meanings and the more well-known Hebrew meaning, mentioned earlier in reference to the Old Testament [ 9 ].

It is not clear whether the Olive Tree has any connection with the Tree of the Knowledge of Good and Evil, as when Adam – dying – sent his son Seth to bring him the three seeds of the Tree of Sin, he obeyed and, after his father’s death, he planted the seeds on Adam’s tomb, from which a cypress, a cedar, and an olive tree grew.

Whatever the origin of the symbol behind this particular plant, it teaches us the need for renewal and regeneration, as well as the great ability to pacify one’s feelings with those of God or the Universe, however you want to call it ( Figure 4 ).

Peace dove.

The only certain thing about the history of the olive tree is that it could not be a more suitable plant in the vegetable kingdom to represent the Christian Easter and the whole spring period in general.

The olive tree and olive oil have always seemed to instill in the observer a profound sense of the sacred. It is no coincidence that they play an important role in the three monotheistic religions of the Mediterranean, Judaism, Christianity, and Islam. The oldest written testimony on the olive tree is found in the Old Testament, the sacred book of Judaism, in the episode of the Great Flood: Noah waited another seven days and again sent the dove out of Ark. In the evening, the dove returned to him: and behold, it had an olive branch in its beak. In Christianity, we remember Palm Sunday, which commemorates the entry of Jesus into Jerusalem welcomed by the crowd waving olive branches and palm trees. The oil is also used in baptism, in the consecration of priests, in the anointing of the sick, and in confirmation. As for Islam—in Paradise, there are two taboo trees, the olive tree and the fig tree.

The very name of Christ means “anointed,” a Greek translation of the Hebrew term mašíakh used as an adjective that designates the person who was anointed with oil in the consecration ceremony. In the Christian religion, the olive tree has a strong symbolic value, the olive branch pinched in the dove’s beak, for example, marks the end of the flood, symbolizing peace and regeneration. Even in Jewish religious rites, oil is very important and the theme of anointing as a consecration to the Lord returns. A series of food taboos have also emphasized its importance, the Torah, the fulcrum of the Jewish religious tradition, in fact, prohibits the consumption of most animal fats, helping to make olive oil the main ingredient of Jewish cuisine. The olive tree, in addition to being present in Greek mythology in an important way, is also known in the Arab tradition, which, however, based most of its current doctrine on the teachings of Muhammad and also traces to a large extent pre-existing beliefs that, so as happened within the Christian religion regarding pagan cults, they had to be implemented by the Prophet in the global order of the new religion. In the Koran, the sacred text of Islam, the olive tree is defined as “the blessed tree,” while the anthropologist Edvard Westermarck, in the essay Ritual and Beliefs in Morocco, wrote: “in Islam, it is the cosmic tree par excellence, center and pillar of the world, symbolizes the universal man, the prophet.”

Generally, in religious language, the olive tree has always represented the promised land; it has always been a message of fertility and divine blessing (a message which, among other things, is common to several religions). In old times, olive growing was in fact among the main agricultural activities, and oil, obtained from this tree, along with cereals and wine, represented one of Israel’s heritage. The olive tree and the resulting oil were in fact signs of abundance and well-being.

In the Bible, more than in other religious texts, it is present in numerous episodes and has a much stronger symbolism than in other religions. However, the fact that the olive tree is present in the most ancient texts and that it is part of several different and distant cultures historically and geographically, makes us understand how important and ancient the culture is linked to this tree.

4. The olive tree in art

The culture of the olive tree and its fruits has deep ties not only in the gastronomic traditions of the different populations of the countries that overlook the sea “nostrum” but so permeates the civil and religious culture of the various nations that often they have based their own economic survival on the production of olives. Perhaps no tree like the olive has moved from cultivation to culture, each becoming an integral part of the other.

In the course of history and literature, numerous artists and writers have dedicated prose passages and poems to the olive tree, a plant that, due to its strength and structure, has always fascinated man and has become the tree par excellence, the protagonist of stories, tales, and myths.

Ode, canto, what a beautiful image comes to mind when quoting these two words. What if an ode was dedicated to food? It was Pablo Neruda, pseudonym of Ricardo Eliécer Neftalí Reyes Basoalto (1904–1973), poet, diplomat, Chilean politician, Nobel Prize for literature, who generated this great idea. In the Ode to Wine and Other Elementary Odes, Neruda celebrates wine, bread, onion, tomato, oil, potato, and other foods, apparently so mundane, of which we do not realize their immense value. The poet approaches poetry with small things, giving them a new identity.

Evergreen and millennial trees are symbols of peace, hope, and resistance, the olive tree is already present in the sacred texts of the three major religions in the world, and from then on many writers have used this plant as a subject or metaphor in their texts or in their paintings.

With its leaves with iridescent, silvery reflections, whose delicate lines are highlighted by the branches and gnarled trunk, the olive tree represents in the collective imagination a sort of sculpture made by nature itself, also for this reason, in the history of art it has been the privileged subject, a constant source of inspiration for artists, also as a symbolic representation of virtue, dogmas, images, feelings, affections, and emotions [ 10 , 11 ].

The olive tree has been represented in many religious paintings. The image of the olive tree is often the element with which the artist guides the observer on a path of didactic references

In the historical-artistic context and in particular, in the iconography of the Virgin and the Passion of Christ, the image of the olive tree is often the element with which the artist guides the observer in a path of didactic references, as on the figure of Maria Regina Pacis, parent of the Savior of the world.

An example is Giotto’s Entry of Christ into Jerusalem , in the Scrovegni Chapel in Padua. The scene is composed of an amiable realism, very evident in the figure of the donkey, placed in the foreground, and in the atmosphere that the image itself, as the artist conceived it, generates in the viewers ( Figure 5 ).

Entry of Christ into Jerusalem by Giotto. Scrovegni Chapel, Padua.

In the twentieth century, the olive tree was defined, in all respects, as a natural element of the landscape, as a symbol of a pure, and authentic beauty that everyone, poets, writers, artists, can capture and be aware of its fascinating artistic significance.

Another notable example is the Annunciazione by Simone Martini and Lippo Memmi in 1333 (Uffizi Gallery in Florence).

The young archangel, kneeling in the manner of a noble knight, hands the Virgin an olive branch, a symbol of the peace and universal harmony that the unborn child would spread on earth. She wears an elegant damask dress (whose golden color reflects Gabriel’s nickname, known as the “messenger of light”) and a lively checkered cape ( Figure 6 ).

Simone martini annunciazione.

Sandro Botticelli, in the painting The return of Judith to Bethulia (c. 1472, Uffizi Gallery in Florence), places an olive branch in Judith’s hand, symbolizing the rediscovered peace after the death of the Assyrian king Holofernes. This work, together with the other protagonist of the diptych, Discovery of the corpse of Holofernes , constitutes one of the first narrative paintings we know of by Botticelli ( Figure 7 ).

The return of Judith to Bethulia. Sandro Botticelli, Uffizi Gallery, Florence.

The two protagonists are portrayed by Botticelli while they are on the run, with the enemy’s head covered with a sheet, and Giuditta, while with one hand she holds the murder weapon or the saber, and with the other, she holds an olive branch, a typical symbol of peace.

Another religious example in which the Passion of Christ and the olive tree are intertwined, just like one of its branches, is that of El Greco’s 1590 painting Christ in Gethsemane (National Gallery of London). In his unmistakable style with elongated objects and figures, the plant is a characterizing element as it is placed in the foreground to the left of Christ, thus making the viewer participate in the story. In it, moreover, the olive tree foreshadows the death of Christ and the peace to which humanity is destined by the will of God following the sacrifice of the son.

A further tribute to the sacredness of this tree and its fruits can be found in the marvelous Madonna dell’olivo by the Genoese Niccolò Barabino of 1888 in which the very pure Virgin in white hugs the baby Jesus who in turn holds a twig of olive tree, once again a symbol of peace and salvation ( Figure 8 ).

Madonna dell’olivo by the Genoese Niccolò Barabino. Church of S. Maria della Cella in Sampierdarena – Genova.

The olive tree whose branches take on the same color as the background is placed at the back of the scene and in turn, completes the triad of the embrace (Madonna, Jesus, olive tree) in a global way, thus framing the picture and letting you imagine its continuation. beyond the perimeter.

Still in the same century but 50 years earlier, the landscape current of Realism and Naturalism spreads in France, connected to the school of Barbizon, a small town near the forest of Fontainebleau, whose painters, despite differing in style and temperament, are strongly linked because they share the same desire to discover the beauty of Nature. This will be the backbone of a new movement that will soon spread, Impressionism, through which painters bring to completion “[…] the accentuation of the perceptual moment over the fantastic” by painting en plain air.

Based on these assumptions, Van Gogh, the movement’s leading exponent, in 1889 dedicated approximately 18 canvases to the representation of the olive tree in the autumn during which he was hospitalized in the psychiatric hospital of Saint-Rémy-de-Provence for serious emotional and nervous difficulties. For him, the olive trees represent life and its cycle, the divine, and how the relationships between man and nature can connect the former with the divine. Furthermore, for the painter, being in harmony with nature means creating moments of idyll and contemplation ( Figure 9 ).

Representations of olive trees by Vincent Van Gogh.

National Gallery of Art in Washington summarizes this series:

“In the olive trees – in the expressive power of the ancient and gnarled forms – Van Gogh found the manifestation of the spiritual force that he believed to reside in all of nature and his brushstrokes make the ground and the sky alive with the same movement of the rustling leaves, mixed to a shimmer by the Mediterranean wind. The energy in the continuous rhythm communicates to us, in an almost physical way, the living strength that Van Gogh found among the olive trees; that spiritual force that he believed took shape there.”

5. A second product: landscape

In reality, the “landscape” is a vast and difficult subject to circumscribe also because it is a concept that has undergone a profound evolution over time. The European Landscape Convention, Florence, 20.X.2000 defined that “The member states of the Council of Europe signatory hereto,…. Noting that the landscape has an important public interest role in the cultural, ecological, environmental, and social fields, and constitutes a resource favorable to economic activity and whose protection, management, and planning can contribute to job creation; Aware that the landscape contributes to the formation of local cultures and that it is a basic component of the European natural and cultural heritage, contributing to human well-being and consolidation of the European identity;….” [ 12 ].

The landscape is, therefore, the heterogeneous set of all the elements, processes, and interactions that make up the ecosphere, considered in its unitary and differentiated structure and in which the activities of nature and man are integrated, in their historical dimension. Material, cultural, and spiritual.

“Cultural Route of the Council of Europe” certified in 2005 that “The presence of the olive tree has marked not only the landscape but also the everyday lives of the Mediterranean peoples. As a mythical and sacred tree, it is associated with their rites and customs and has influenced their lifestyles, creating a specific ancient civilization, the “Olive Tree Civilization”: the Routes of the Olive Tree follow in the footsteps of this civilization, from Greece toward the Euro-Mediterranean countries. The olive tree dates back millions of years. Wild olive trees, ancestors of the domesticated ones, can still be seen in the Peloponnese, Crete, North Africa, and the Middle East, their places of origin. The relationship between this tree and human civilization has produced an immensely rich, living cultural heritage, embedded in the everyday habits of the Mediterranean people. From gastronomy, with the crucial influence of olive oil, to art and traditions, the social development of these areas has been largely shaped by the olive tree” [ 13 ].

The olive tree participates in the formation of a multiplicity of landscapes in relation to the different cultural structures that have been defined in the long process of adaptation of the species to the different environmental characteristics of the places. uneven orography of the most disadvantaged areas, to the more or less specialized systems of the hilly areas, to the intensive monoculture of the plains. In addition to the landscape diversity dictated by the cultivation practices, strongly changing aesthetic connotations are impressed on the territory by the different olive models adopted, the result of that continuous centuries-old adaptation of cultivation techniques to environmental conditions, whether linked to the company structure and to the edaphic and climatic conditions or the economic and social structure that has gone through human history, where the olive trees were associated with a myriad of other crops, which ensured the livelihood of peasant families, reinforcing the typical geometries of poly-cultural systems (olive trees placed at the edge of the vineyards or between the rows, inserted together with almond and carob trees, confined within the vegetable gardens or placed at the edge of citrus groves) or interrupting the monotony of progress of arable land ( Figure 10 ).

Some examples of landscapes characterized by the presence of olive trees.

With the development of olive growing in vast territories of the island, and particularly starting from fifteenth to eighteenth century, the presence of plots with higher specialization, it begins to become more consistent, to the point of characterizing, in subsequent phases, the crop structure of entire territories, especially hilly areas. This singular olive type, defined as “traditional,” still constitutes wealth for the area today due to the important role it fulfills in hydro-geological defense and in the qualification of the landscape. As a result of the millennial interaction between different environmental, social, and cultural factors, it is still possible today in many countries to find the numerous systems and landscapes of the olive tree that have accompanied its history.

In the most marginal conditions, on sloping land, on the narrowest terraces, the olive tree participates in the formation of the systems and landscapes of mixed cultivation where these systems survive the rural exodus of farmers.

These olive-growing systems frequently constitute tiles within a mosaic formed by very fragmented agricultural systems of different types and with high landscape diversity. Olive groves which, thanks to the capacity of self-regeneration, typical of the species, have resisted over time giving rise to specimens of large and very large dimensions defined by Pirandello Saracens for their almost legendary antiquity. Where the orographic conditions are more favorable to productive rationalization processes, the olive cultivation becomes more specialized while only partially maintaining the characteristics of traditional olive-growing systems. Some modifications of the cultivation model which concern the containment of the volume and height of the canopy contribute to differentiate it, to favor and economize the practices of defense, pruning and harvesting, and a reduction of the planting distances, which become regular, to increase the productivity of olive groves. It is amongst the olives grown for oil that it is difficult to indicate a single type of plant. As a result of the different densities adopted, the distances and the planting width vary, with evident reflections on the geometry of the olive groves. In many cases, the plant model and its landscape impact depend on the genotype and, in particular, on the bearing of the plants, on their vigor as well as on morphological characteristics, such as shape, size, and color itself, of the leaves.

Literature also highlights the qualities and prerogatives of the olive tree: its resistance to time and bad weather, the usefulness of its fruit, the sense of peace and serenity that it gives to men with the soft and pale green of its branches. The olive tree is a resistant plant—it sinks its roots firmly into the stony ground, it takes many years to become a plant that bears fruit, but, as it was slow in growing, it lasts a long time. It binds several generations together, giving fathers the satisfaction of having planted a tree not for their own good, but for that of their children and posterity. The fruit of the olive tree is precious because the oil not only gives nourishment but also light in the lamp; and like light, it accompanies us to the deathbed. Undoubtedly the olive tree is a plant that inspires feelings very close to those of the poet: peace, which is the opposite of the hatred depicted in old castles (manors); generosity toward others (the precious gift of its fruit); goodness, which is the opposite of badness.

6. Final considerations

Traditional olive-growing agroecosystems constitute tiles within a mosaic made up of agrarian and semi-natural systems of different types, very fragmented and with high landscape diversity. Even at the farm level, biological diversity remains high both in the case that the olive tree is part of a poly-cultural system and in the case of olive groves conducted in conditions close to semi-natural. Olive trees are grown according to the knowledge and practices that include the use of different types of terracing, cultivation techniques, and genetic varieties that have been maintained for centuries by local communities. This extraordinary landscape made up of olive trees was shaped by the ancient interaction of farmers with the environment.

The countries of North Africa have their own landscape defined by the olive tree. A typical example is the desert area of Tunisia and Morocco where the olive tree naturally grows mainly in the valleys using the little humidity present. Tunisia is a land of olive trees, a place where the olive tree over the millennia has been infused with the culture, economy, cuisine, habits, rhythms, seasons of the nation. Some Tunisians even anoint babies with olive oil ( Figure 11 ).

Olive Tree in Tunisian landscape.

Multifunctionality has now become the strategic choice undertaken by many farms which, at various levels, carry out various activities to respond to the negative effects deriving from a system mainly oriented to the production of material goods of industrial origin. For agricultural enterprises, multifunctionality represents a “new” way of organizing production factors (internal resources) and interacting with external resources (the territory), aimed at pursuing economic, environmental, and social objectives in the medium and long term. Seen from a more general perspective, multifunctionality represents one of the key points in the development process of the agricultural sector and the rural world. The role of agriculture, in fact, for several years now is no longer exclusively attributable to its function of producing basic necessities but expands through the recognition and performance of other environmental, social, landscape, historical, cultural, etc.

Multifunctionality actually places agriculture, in its renewed value as a producer not only of traditional goods but also of other goods, at the center of the interest of the economy and citizens. Among other things, multifunctionality is not an exclusive trait of small businesses nor, much less, of marginal agriculture, although multifunctionality can be a strategy aimed at improving the remuneration of the small family business. In the countryside and the primary sector, new economic models are being developed that, looking at the past, at peasant values, at traditional resources and methods, are innovating, revisiting schemes, creating new perspectives, including economic ones; it is agriculture in which future and tradition merge and are declined in retro-innovation—drawing on the experience of the past and enhancing previous knowledge, reinterpreting and using them in contemporary contexts and circumstances, to try to give answers to the needs of the present and above all to ensure that they do not turn into the emergencies of the future.

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• 13. Available from: https://www.coe.int/en/web/cultural-routes/the-routes-of-the-olive-tree 2005

© 2022 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution 3.0 License , which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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“The Olive Trees” by Vincent van Gogh – “The Olive Trees” Analysis

The Olive Trees (1889) by Vincent van Gogh is one of around 15 versions of olive trees that the famous Dutch artist created and explored when he lived in France. This is the painting that will be discussed in the article below.

Table of Contents

• 1 Artist Abstract: Who Was Vincent van Gogh?
• 2.1.1 Companion Painting: The Starry Night (1889)
• 3.1 Subject Matter: Visual Description
• 3.2 Texture
• 3.5 Shape and Form
• 4 Van Gogh: Nature in the Brushstrokes 
• 5.1 Who Painted The Olive Trees?
• 5.2 How Many The Olive Tree Paintings Are There?
• 5.3 Where Did Vincent van Gogh Paint The Olive Trees?

Artist Abstract: Who Was Vincent van Gogh?

Vincent Willem van Gogh is one of the most well-known artists from the 19 th century. His date of birth is March 30, 1853, and his date of death was July 29, 1890. He was a Dutch artist, born in the town called Zundert, in the Netherlands.

His style of art has been categorized within the post-Impressionist art movement and is characterized by his expressive use of brushstrokes, arrangements of colors, and subject matter that ranged from portraits, landscapes, flowers, and people from all walks of life.

A lot can be learned from his correspondence with his brother Theo van Gogh; the brothers wrote extensive letters to one another, and although he lived a short life, he made a long-lasting impact on the world. His artworks are on display at prominent art galleries as well as at the Van Gogh Museum in Amsterdam. Vincent van Gogh’s famous artworks include The Starry Night (1889), The Potato Eaters (1885), and Almond Blossoms (1890).

The Olive Trees (1889) by Vincent van Gogh in Context

The Olive Trees by Vincent van Gogh is also sometimes referred to as Olive Trees in a Mountainous Landscape or Olive Trees with the Alpilles in the Background . It is an oil-on-canvas study that was deeply meaningful to the artist, which we will explore further in the contextual analysis below. We will also provide The Olive Trees analysis in terms of its formal qualities and examine Van Gogh’s composition of the subject matter.

Contextual Analysis: A Brief Socio-Historical Overview

When Vincent van Gogh painted The Olive Trees in 1889, he was living in southern France in Saint-Rémy-de-Provence at a mental institution called the Saint-Paul Asylum. He explored the natural environment during his time there, painting the scenery that consisted of wheat fields, cypress trees, flowers, as well as olive groves. He also had a painting studio from which he worked at the asylum.

However, his exploration of the natural environment was driven by a deep connection that he felt with nature, and he reportedly found solace in it and comfort during his illnesses. He often wrote about his awe of nature to his brother Theo van Gogh.

For example, in a letter dated around January 1890, Vincent van Gogh described to his brother how he got up during the night to look at the landscape: the snow was melting as it fell, and he explained that “never, never has nature appeared so touching and so sensitive to me”.

Companion Painting: The Starry Night (1889)

The Starry Night by Vincent van Gogh was reportedly The Olive Trees painting’s companion piece. In a letter that Van Gogh wrote to his brother he described the two paintings, stating that the olive trees “with white cloud and background of mountains, as well as the Moonrise and the Night effect”, are “exaggerations from the point of view of the arrangement”.

Additionally, Vincent van Gogh further compared the lines to “ancient woodcuts”. Interestingly, he was influenced by and loved Japanese woodblock prints; he also owned an extensive collection of them. 

Formal Analysis: A Brief Compositional Overview

In this section, we will provide a discussion of the visual composition of The Olive Trees by Vincent van Gogh, as well as an analysis of his artistic style in accordance with the art elements like color, texture, line, shape, form, and space, respectively.

Subject Matter: Visual Description

The Olive Trees painting by Vincent van Gogh depicts an olive grove in the foreground, with mountains in the background and a sky with clouds. Almost every part of this composition is alive with rhythm, movement, and color.

There are two cloud formations in the blue sky above.

Towards the top left corner is a small, almost ovular S-shaped white cloud. To its right is a larger, light (or “pale”) yellow and white cloud with a thin tail (almost like an umbilical cord) from the top border of the composition, which forms into a larger accumulation of swirls in the top center, right above the middle mountain range. 

Below the blue band of the sky with clouds is the Chaîne des Alpilles, which is a mountain range in southern France and what would have been one of Vincent van Gogh’s views, forming part of the subject matter of numerous of his paintings.

In this composition, the mountains are a dark bluish-purple color.

In the foreground, nestled below the mountain range, is an olive grove, depicting around four or more trees and the ground below them. The trees appear lush and bushy with their green leaves, and their stumps are visible in the ground. The ground below does not appear flat, but up-heaved and undulating. It is a combination of greens, yellows, blues, and whites.

The yellow on the ground has been described as the subtly shining light from above.

The texture in The Olive Trees painting is dynamic and Van Gogh’s brushstrokes are tangible on the canvas with a variety of types like thick, thin, short, and long – all fluid and expressively applied. For example, the sky consists of short swathes of brushstrokes, seemingly haphazardly applied.

The foliage of the trees consists of curvy, almost arabesque-like, and choppy brushstrokes while the ground below appears in longer and curvy horizontal bands of brushstrokes.

Vincent van Gogh composed The Olive Trees painting through fluid brushstrokes, which are visibly evident and create various types of lines. There are curved, curly, and spirally lines, all organic (naturalistic), which gives the composition harmony and movement created by the rhythmic flow of the lines.

Additionally, there is also a pattern created by the repetition of the types of lines.

The Olive Trees by Vincent van Gogh depicts various shades and tints of green, blue, and yellow with whites and black. Interestingly, blue held a symbolic meaning to Van Gogh – reportedly, it symbolized the “divine”, which the artist sought to convey through his pictorial compositions. 

Shape and Form

There are organic and naturalistic shapes and forms in The Olive Trees by Vincent van Gogh, for example, the swirling form of the large cloud in the sky, the craggy mountain tops, the bushy forms of the trees and their crooked stumps and branches. The ground appears less “realistic” and more undulating, as if it is flowing.

This hints at Van Gogh’s deeper perception of the environment, which was not wholly true to reality.

The compositional space appears in bands of thirds and can be viewed as foreground, middleground, and background.  There is a three-dimensionality in The Olive Trees painting, created by the dark colors of the mountains in the background and the slightly lighter colors in the foreground on the trees and ground.

Furthermore, there is a sense of distance created by the size of the mountain tops in the background, which appear slightly smaller than the trees in the foreground.

Van Gogh: Nature in the Brushstrokes 

Vincent van Gogh was not only a painter but a lover of nature, which he had a deep reverence and appreciation for from a young age. Some also say that his art was intricately connected with nature, and we can even say nature was intricately connected with his art. He often painted outdoors and would write about how he saw the more spiritual aspects of nature in many of his letters.

In this “The Olive Trees” analysis, we discussed when Vincent van Gogh painted it and the deeper meanings related to it, as well as his stylistic approach. What we see as a painting with olive trees is truly a painting seen through Van Gogh’s heart and soul, nature is not only an image, but it is in the physical brushstrokes too. 

Frequently Asked Questions

Who painted the olive trees .

The Olive Trees (1889) paintings were created by Vincent van Gogh, who was one of the most popular post-Impressionist artists who primarily achieved posthumous popularity. He created numerous renditions of olive trees and the surrounding natural environment when he lived at the Saint-Paul Asylum. 

How Many The Olive Tree Paintings Are There?

Reportedly, Vincent van Gogh created around 15 versions of The Olive Tree paintings, all depicting different times of the day. Some included figures like a couple walking at night, and others depicted women and men in the process of picking olives. The versions also held symbolic meanings related to the divine, the so-called life cycles, as well as nature.

Where Did Vincent van Gogh Paint The Olive Trees ?

Vincent van Gogh painted The Olive Trees painting series when he lived at the mental asylum in Saint-Rémy-de-Provence in the South of France. Reportedly, he went there after he suffered from a mental breakdown in 1888 when he lived in Arles, which was just after he lived in the Yellow House with his fellow artist and friend Paul Gauguin . 

Alicia du Plessis is a multidisciplinary writer. She completed her Bachelor of Arts degree, majoring in Art History and Classical Civilization, as well as two Honors, namely, in Art History and Education and Development, at the University of KwaZulu-Natal, South Africa. For her main Honors project in Art History, she explored perceptions of the San Bushmen’s identity and the concept of the “Other”. She has also looked at the use of photography in art and how it has been used to portray people’s lives.

Alicia’s other areas of interest in Art History include the process of writing about Art History and how to analyze paintings. Some of her favorite art movements include Impressionism and German Expressionism. She is yet to complete her Masters in Art History (she would like to do this abroad in Europe) having given it some time to first develop more professional experience with the interest to one day lecture it too.

Alicia has been working for artincontext.com since 2021 as an author and art history expert. She has specialized in painting analysis and is covering most of our painting analysis.

Learn more about Alicia du Plessis and the Art in Context Team .

Cite this Article

Alicia, du Plessis, ““The Olive Trees” by Vincent van Gogh – “The Olive Trees” Analysis.” Art in Context. November 15, 2022. URL: https://artincontext.org/the-olive-trees-by-vincent-van-gogh/

du Plessis, A. (2022, 15 November). “The Olive Trees” by Vincent van Gogh – “The Olive Trees” Analysis. Art in Context. https://artincontext.org/the-olive-trees-by-vincent-van-gogh/

du Plessis, Alicia. ““The Olive Trees” by Vincent van Gogh – “The Olive Trees” Analysis.” Art in Context , November 15, 2022. https://artincontext.org/the-olive-trees-by-vincent-van-gogh/ .

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The Most Famous Artists and Artworks

Discover the most famous artists, paintings, sculptors…in all of history! 

MOST FAMOUS ARTISTS AND ARTWORKS

Discover the most famous artists, paintings, sculptors!

Culture , Ecosystems , Philosophy , Place

Ancient olive trees.

May a man look up from the utter hardship of his life and say: let me be like these. Hölderlin, In Lovely Blue.

1 Circa 1400 BCE. An olive tree in Vouvés, Crete. From ‘vouvismos’ meaning the whispering of the river flowing through. It wasn’t the only thing that lived then. There were many: cicadas and acanthus flowers, cacti and turtles, grasshoppers, boars, lions and axe-wielding men and priestesses, to name a few. But from then it is all that has survived. 

The word ‘survive’ and its taste in the mouth before all taste had been avoided in fake- grass facades of cities, in changing exteriorities, monuments to myths razed. Leaves, those petals regenerating over centuries, have the same texture, color in the arid land, display the same lilting angles across fragile pale-green stems as they did when Minoans tightened their grip on double axes and ravaged the fields to feed their circular hearths. 

The white-knuckled grip of a Cretan must have slackened as he beheld it, again, through the eyes of the Minoan from which he descended, shimmering at sunset when all the static shades of green await the promise of dreams—his boyhood tree, the one he climbed into and claimed, where he had met his first embrace, the tree embracing him. 

& so on for other men, other stories towering before them, other firsts, the olive tree that must have witnessed the gazes of occasional gratitude alongside adroit glances of utility, for its bitter golden sustenance and flesh, its endurance & fertility, that even the canopy crowning the hollow warped, twisting like dredged red amphora clay, together they must have clamored with longing for the heavens, the constellation Orion whose protectorate Artemis with arrows had spared. Would the olive tree have not appeared as eternal as the singing starlight of the Pleiades above the harbors, which somehow knew, had always known the ways destinies intertwined like roots above ground, lain bare like a feeling whose intensity ebbs in cycles, births of Phosphorus, dying breaths of Hesperus. 

When at harvest they shook the branches, and onto sheeting the reddish-purple fruit dropped, some spilled, rolled onto dusty slate, & after they had bagged the pulp & it was time to break bread & it was a time in which humans broke bread and delivered in their coarse ware the animal-milled virginal pressings, & there was only the sound of bees humming and grape leaf shivering, grown so close to earth, never trellised never watered, & what we would later deem ritual was one unified vision of the world, so long before that pale abstraction confessed of the unity of the good & the true & the beautiful, before that counterfeit braid there was soul shining, smiling, holding its simple floral cup in the shade of the olive tree.

The olive tree, I feel, knows this: that we should feel the stars as the ancients saw them, unaided in the naked air, breathing & at home & alive. At the center of the hollow, ringed with arachne, an emptiness looms, widens, until the terror of standing still engulfs it. Again, the olive tree knows; there is no running off like the 2 nd century Cretan boy afraid of its majesty and rule. Instead, you encircle, as though limbs’ maneuvering might suffice as some default tcchne , a mode of perception when eyes fail to discern, you encircle circumspectly, not as a perambulating disinherited scholarly castaway, but as you might approach some dazzling conception, as Dante did with foresight & his michael & Virgil  & gabriel, his vision muted by the sophistic arguments of Beatrice. 

Yet this is no circling gradual approach, as Petrarch nearing his day’s hike summit. This vision is too humble, inviting, too much the same as actual olive wood, marbled as land and sea, smooth, that makes the cups, the axe handles, carts & cradles. Not that sight has failed, but it cannot encompass immensity. Fingers sliding on bark in a groove like rocksalt, quickly by the undersides of leaves twirling in light wind, grazed in their own sporadic, spoiled summers—they are a sort of pretense of knowledge of the olive tree and olive, turning and returning, as if each finger-stem of ours were its own collaborator in calligraphic rune, in some final epigraphy we by necessity leave incomplete. The dust walks away with us that the olive tree had nourished, away from that focal point & center where we were. 

In the hollow’s boundaries (which are not those of the roots), the significance of the phrase ‘we were’ is changed. An ephemeral living being is contained within the felt walls of the eternal, & in encircling knows it, flees. Standing in the olive tree gratitude can pivot to dread, through this recognition of mortality in the face of relative changelessness. It is better that gratitude, in the broadest sense of the term, welcomes dread than never surface. 2 The olive tree must also have witnessed the cushioned awareness of families at play, the mother, nursing, the father & boys fitted to their stable norms, oblivious investitures of each generation living on, hoping to live on in the next, snakeskins shed at the gnarled base of the olive tree, spring’s empty promise of regeneration. 

Cutting through all those hopes, reiterated across eons, there was only being, being there , growing, lasting, with no regard nor disregard to ‘outlasting’. This way of witnessing, of bearing witness to species’ martyrdom, was nonetheless something, being somehow though we lack a term for it—maybe: ‘continuous structuring of its autonomous, chthonic own’. Opposite those inside, who go & wash their olive wood plates & forks & bowls. Who chop down trees for shrines of great renown. The boy who makes sure, as Sappho imagines, that the sheep by the light of Hesperus return to their fold, ‘& goats to their pen, & the boy to his mother again’. Much, much later, the child who never grows to see himself as a creature of the earth.

Sipping grape-must raki in the tranquility of the night air, after chores were complete, the people would have gossiped as people do, & those wares of olive wood carefully stowed away would have rested, moulded in the darkness of their disutility. The paradox then, was this, that after some amount of time (who can say?) it became taken for granted that this , like other similar olive trees, was sacred, untouchable, its presence part and parcel of some overall ‘experience’ one should have, a thing worthy of appreciation on a par with ancient mosaics and frescoes, to be experienced as though already history, subject to narrow interpretation and ongoing commodification.

Yet the living part of history strikes through the facile horn of paradox for those who would allow it. When your own descendants allow themselves to be enfolded in its graces & with goosebumps gaze through & through the encompassing wreckage of city light & sound, open to that wonder, the dreadful gratitude they have sought, which silenced their distant ancestors midspeech—what memory of yours, then, could intrude, to what destination, then, will the 21 st century humans have gone?

The harshness of the conditions of survival is not reflected in brittleness, as we see in miniature tree-like cave calcite found in Lavrio. In the latter case the mineral is older but indescribably more fragile. What we might feel as the olive wood’s hardness is the centuries-long attainment of pliability immeasurably more elegant than our airfoils, the determined resistance to deluge, storm surge, earth tremors dislodging rock, entrenchment in the face of dallying erosion. Much as the flexible yet firm planks of a trireme weathering aloft the churning sea, when an olive tree’s branches buoy, flooded with sudden gusts of wind (though this far inland they would have partly dissipated) there is no particular stress point, nothing susceptible to fatigue, at ease the olive branches shake their leafy yards, variously along the trunk’s main mast, & if a tattered sail is left the vessel is nonetheless afloat, the wind had fled its flight. 

At times you see a trail of ants or even termites making of the olive tree a home, carrying in an almost Germanically orderly trail stores for their larvae, delicate steps completely absorbed in this task they are oblivious to the olive tree as a tree , its general shape & contour which we in tracing & encircling attempt to express, massage into some idea before it is lost again, the matter of measure, of balance, the fluid in our inner ears as our heads in vain rotate towards the above abyss, to try & picture the whole dangling threshold as our own feet, miss-stepping loose rocks betray our nature as walkers on flat land, as rovers come down from the trees for a ramble on two legs through the grasslands, eyes and knitted brows pointed always toward the next horizon. Indeed, hardly a greater disparity in their nature can exist than between the olive tree’s manifold convolutions & the thin-sharp horizon jutted out each evening, a straight dock flattened out over the entire Aegean, which you feel if you could surpass there would only be a great line, without width geometrically impossible, made of concrete and firmament. They are as contrary as with-standing and encircling, judgment and naïve perception. 

When we theorized about the giant boulders, dispersed fairly evenly amongst themselves, yet concentrated in the village of Volax on Tinos, the taxi driver told us how the boulders came to be. They didn’t slide down from Poseidon’s sweaty arms, or up through the ash plumes of Vulcan, rather all the gods hurled even larger rocks as they battled each other, these were the crumbled bits of a war. The myth ‘explained’ both the size and the distribution of the boulders, and seemed a good abduction if it was the nature of the gods to grow tired of such play. 

Which being curried such favor with the gods, that while short of the station of Herakles, they would—from such a virtuous human seed—have grown here, in the soul at Vouvés, rendering outwardly visible these innate strengths? Or could it have been from a tear Vulcan shed in remorse, over his destruction of Minoan civilization, one drop sufficient to nourish for thousands of years a humble olive tree symbolic of the craft of humans, perhaps such a tree in whose shade some other Jesus stood, and wept, and hardly noticed. 

As a maxim: the most virtuous inner world finds an outward expression in an olive tree.

In the oldest olive trees there is always the appearance of two trunks, each considered large on its own, growing side by side, with nearly equal exposure to the sun. The knobby scars of past blights imposes, presses itself into the felt gradient of thick bark as welts, lumps from healing, traces of constricting vines which nearly destroyed the young olive tree. The truism that suffering strengthens if it does not destroy forms into the literal shape of a fist as your palms buffet the surface of the tree, you lean in on that soft, just that pressure point which ached centuries ago from its dendritic bubonic plague, until the balm of Aeolus, the salt-rind scent of tamarisk trees soothed & shifted the tenuous balance, to life. 

The contingencies we reflect upon, which motivate & militate us from our condition, to reject our natural state as living beings, are as mobile as our bodies in their healthy normalcy, which is to say, always mobile, hopeful to a fault. ‘Man exists in measure. Well-deserving, but poetically man dwells on this earth’, Hölderlin writes in ‘In Lovely Blue’, well-aware of the impossibility of rootedness. For the ancient olive tree of double-trunk, languishing in the hard sun, rootedness meant no more & no less than this: with-standing. One can readily imagine why priests & devotees of Asclepius would have planted olive groves, along with cooling cypress, oak and pine, not for ‘hope’ of the terminally sick, but to virtue signal endurance, with the irony that it was they who in uprooting themselves from their villages were most desperate for a cure. Aren’t we all like the gardeners stooping to graft an olive branch, pilgrims in search of some measure of life’s continuities?

At best, there can be longevity. A brief existence in which to parlay, to make a few trenchant observations. I think of those old men I met in the ‘blue zone’ of Ikaria, who sit on their long olive benches outside the deserted city hall smoking, retelling shepherds’ stories, who then throwing off their towels wade into the waters near the hot springs bubbling sulfurously, grateful for their fortune, & each attributing it to something uniquely theirs: the water, the cigarettes, lack of children, occupation, daily doses of raki, fish, a particular way of life. As though there had to be some reason for longevity whose precious possession might be lost unless they reveal it, always at the end of the conversation and with the disclaimer (or what has the undermining force of a disclaimer): well, that’s my story , that’s my life.

What does an olive tree say, what could it say when you gently pat its worn divots & surely as others ask its secret, what possible truth could it disclose to you which it hasn’t already, simply by being present? (As it is completely present in all its faculties). Then when in some museum you see on display the preserved, persevered, rings delicately edged by blackish cracks running perpendicular to the grain & an adjacent diagram neatly explains their meaning, what is there but to shrug in sadness and move on, a little less hopeful than before about the worth & purpose of human longevity. 

But then, at times you do meet an old Yaya who lives in the next village over & through her wrinkles smiles back at you with her eyes, sidestepping any felt need for mutual recognition having as its basis a shared language, yet seeming at once to say that the secret is there is no secret, she says it in the faint language of the olive trees.

By way of inelegant postscript this essay was composed on a direct flight from Athens to JFK. As the uncontrollable Canadian wildfires raged, smogging the atmosphere & and raining down over NYC tens of thousands of what headlines vaguely described as ‘tiny bugs’, the pilot in officiously gentle tones reminded us that our approach would be gradual. Sighs fill the cabin. 

As we circled & circled the Long Island Sound the turbulence brought to mind Odysseus and his men clinging to the fat undersides of sheep to escape the Cyclops’s den—we his crew, our plane the sheep—& I paused briefly over whether the red eye of the Cyclops was the far off wildfires blazing, or climate change itself. 

Below us in that still, white seabed of clouds the density of the toxic air brought into quaint relief, here speedboats gliding through the Sound, & there gargantuan footprints padding the downy snow. The tentative myths sometimes necessary to remind us of the force of nature seemed to cut away & drift past my window at eye-level. I turned to my respectful neighbor and asked her point-blank: ‘When does a natural disaster become an international crisis?’ She looked at me as if it were also a question on her mind & replied: ‘I don’t know’. 

I don’t know precisely either, & yet it seemed suddenly clear that to interpolate sacred facets of a natural world worth preserving by focusing much on a single living being at Vouvés is in a despairing sense to fail to see the forest for the trees; from which standpoint the counsel is: be younger, be more easily motivated to act. So I sound a note of discouragement at these interstitial probings, but I’m trying to be honest. 

In a moment of turbulence I clenched my jeans, streaked black from the charred olive trees whose hellish ornaments still hung on embrittled limbs bent and snapped back while I traversed and tramped, angling between the spiked centauri amid the ruins of Besa, where Roman glass had ground to dust and air is sage and dictamus, hundreds of scorched skeletons seemed to hiss at that border which by pure convention is assumed to separate urban from rural, wilderness from civilization, despite the fact that skeletons everywhere, of any kind, whether resting above or below stones, are the same. 

A Minoan-era olive tree reminds us most of absence: how when no other living thing here was living, it was bearing fruit, its pale grey green sheath, amplified by the restless orange stare of sunset, rustled by the paths of wild boars. But in the field walking and its traces on my jeans was a more recent absence present. In those chaotic, avant-garde striations it was too late for there to have been any pattern to ‘master’ or predict; thinning airy layers of vapor into which our clumsy metal descended contained nothing more of their origin & substance. 

‘They say breathing that for one hour is like smoking thirty cigarettes’, she said, pointing out the porthole at the grey sea. I couldn’t help but nod my head in shame, as we were back now in the land of the free. Taxiing, taxiing. It was just another day at JFK. 

1 For those philosophically inclined, it may be useful to note as a point of strategy underpinning an essay like this, that one might start with some received list of virtues, esp. those considered to belong to the Greek character, and then proceed viz. example to show how those virtues might be grounded in relation to the natural landscape and in particular ancient olive trees; this essay begins instead with the ancient olive tree in its natural setting and proceeds, using historical knowledge and phenomenology, to tease out salient and admirable (‘beautiful’ in the original sense of the word) qualities which might then serve as the basis to complicate and enrich some received list of virtues.

  2 Narrower senses of the word gratitude and its cognates would specify it in relation to a ‘whom’ it is owed, not the ‘what’ of the cosmos.

David Capps

Written by David Capps

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These May Be the Oldest Olive Trees in the World

While the sentinel trees of Northern Lebanon may not be as old as some traditions hold, one tree might be more than 1,000 years old.

By Katherine Kornei

Katherine Kornei has previously reported on the study of tree rings at Viking settlement sites and in Stradivarius violins .

Olive trees are common in Northern Lebanon, but in the village of Bshaaleh, a handful look downright ancient. Their branches grow in wildly unpredictable directions, and the trees’ gray, gnarled trunks are shot through with holes and crevasses large enough to hide a sleeping child. Many people believe these sentinel trees are thousands of years old. They are known as “Noah trees” because of some people’s belief that the trees are the source of the olive branch carried by the dove back to Noah’s ark.

Scientists have now established a more certain age for several of the trees of Bshaaleh (also spelled Bchaaleh) and found that most are about 500 years old. But one, a behemoth measuring roughly 14 feet in diameter, is more than 1,100 years old. That’s the oldest olive tree in the world, the team reported last month in the journal Dendrochronologia.

Not many other large olive trees have been reliably dated, despite the cultural, spiritual and economic importance of such trees in places such as the Mediterranean. Scientifically determining the ages of olive trees is challenging, said J. Julio Camarero, a dendrochronologist at the Pyrenean Institute of Ecology in Zaragoza, Spain, who led the study of the Bshaaleh trees. That’s because these trees often lack regular growth rings, he said. “The rings are not easy to see.”

Most species of trees form annual growth rings. Researchers can count the number of rings in samples of wood extracted from living specimens and precisely determine a tree’s age. That practice has spawned an entire subfield of scientific inquiry known as dendrochronology. Investigations based in large part on analyzing tree rings have shed light on, for example, the timing of the arrival of the Vikings in what is now Newfoundland , and the craftsmanship of Antonio Stradivari, the Italian artisan renowned for his stringed instruments .

But olive trees — which scientists have previously shown can live hundreds of years — often have irregular or even missing annual growth rings. Furthermore, older olive trees can exhibit multiple trunks, hollowed-out interiors and other vagaries of growth that make it difficult to determine their ages. Even professional tree-ring scientists have trouble with olive trees: An earlier study showed that when different tree-ring laboratories received samples of wood from the same olive trees, the labs reported tree-ring numbers that varied by as much as a factor of three.

Given the difficulties associated with counting olive trees’ rings, researchers have attempted to infer the ages of olive trees based on their diameters . However, such age estimates can be uncertain, given that soil fertility, climatic conditions and other factors can affect a tree’s growth. “Size is not the same as age,” Dr. Camarero said.

Olive trees are generally understudied as a result, said Peter M. Brown, the director of Rocky Mountain Tree-Ring Research, who was not involved in the new study. “No one has paid much attention to olives because of the difficulty in doing tree-ring research with them.”

In 2018, several of Dr. Camarero’s colleagues traveled to Bshaaleh, located about 50 miles north of Beirut. With permission from the village’s leaders, the researchers cut samples of wood from 11 olive trees. The team wouldn’t be counting tree rings, so getting a continuous sample of wood from the center of each tree out to its bark wasn’t necessary. Instead, the researchers planned to use carbon-14 dating to assess the oldest wood from each tree.

But even collecting just the innermost — and presumably oldest — wood from the trees was a challenge, said Ramzi Touchan, an environmental scientist at the Laboratory of Tree-Ring Research at the University of Arizona who led the sampling work. In many cases, the trees’ middles had rotted away over time. “You don’t see the center,” Dr. Touchan said. In other cases, the trees were multistemmed, and it was unclear where the oldest wood resided. In the face of all the uncertainty, Dr. Touchan said, “I was not optimistic.”

Back at the University of Arizona, researchers extracted the carbon from each of the roughly half-inch samples. By comparing the relative abundance of two isotopes of carbon — carbon-12 and radioactive carbon-14 — the team inferred how much time had elapsed since that wood was formed. Dr. Camarero and his collaborators obtained reliable age estimates for four trees: Three were likely between 500 and 700 years old, and one was roughly 1,100 years old.

Those ages make sense, said Concepción Muñoz Díez, an agronomist at the University of Cordoba in Spain who was not involved in the research.

But it’s important to consider that the olive trees of Bshaaleh might have been grown by attaching part of a tree onto an existing root system, Dr. Muñoz Díez said.

“They don’t know if the trees are grafted.”

The researchers might have inadvertently collected wood from that older rootstock, Dr. Muñoz Díez said, a possibility given that a grafted tree can grow a mixture of both rootstock and cultivar wood. In such a case, the determined ages would be overestimates, she said.

While Dr. Camarero and his team could not rule out the possibility that the trees had been grafted, he said the opposite conclusion could also be drawn: The ages he and his team recovered could also be underestimates if the samples were derived from the cultivar wood.

Whatever their true ages, the olive trees are living treasures for the people of Bshaaleh.

“They represent the cultural heritage of Bshaaleh’s residents, and they serve as a source of pride and a symbol of local identity,” said Rachid Geagea, who is the owner and caretaker of one of the trees and a former mayor of Bshaaleh.

Every fall, he said, residents of the village gather at the trees to harvest that year’s fruit. Working by hand or with devices that resemble fluttering rakes, the villagers collect hundreds of pounds of green- and purple-hued olives. Some of that fruit is preserved to be eaten, and some is pressed for oil.

People are sometimes disappointed when trees don’t turn out to be as old as expected, said Mauro Bernabei, a dendrochronologist at the Italian National Research Council who was not involved in the research. “It’s almost automatic that when you see these kinds of majestic trees to say that they’re millennial.”

But ascribing an age to a tree doesn’t change its value, Dr. Muñoz Díez said. “For those of us who already know them, cherish them and love them, age is a minor detail.”

Rachelle Alwan contributed reporting from Beirut, Lebanon.

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How to Plant Olive Tree: Tips for Healthy, Fruitful Growth

• March 26, 2024

Kristine Moore

Learn how to plant Olive Trees, symbols of peace, wisdom, and longevity, known for their gnarled trunks and silvery leaves. This guide will walk you through the rewarding process of adding these beautiful and fruitful trees to your landscape, whether you’re aiming to enhance your garden’s aesthetic, enjoy homegrown olives, or connect with Mediterranean traditions.

Olive Tree Benefits

List on how to plant olive tree, choosing the right variety, selecting a location, planting your tree, caring for your olive tree, harvesting olives.

The first step in selecting the right olive tree variety is understanding the climate of your region. Olive trees are native to the Mediterranean, so they naturally thrive in environments with hot, dry summers and mild, wet winters. They are best suited to regions with a long, warm growing season and a winter that’s not too harsh.

Cold-Tolerance

• If you live in an area with colder winters, it’s crucial to choose a variety that can withstand lower temperatures. While olive trees can survive occasional frosts, prolonged exposure to freezing temperatures can damage or kill the tree. Varieties known for their cold tolerance include ‘Arbequina’, which can withstand temperatures as low as 20°F (-6°C), and ‘Leccino’, another robust variety known for its resilience.

• Origin : Catalonia, Spain.
• Size : Small, perfect for containers or smaller spaces.
• Fruit : Produces small, flavorful olives that are excellent for oil production.
• Growth Rate : Fast-growing and begins to bear fruit quickly, usually within 2-3 years of planting.
• Climate Suitability : Adapts well to both warm and moderately cold climates.

• Origin : Spain.
• Size : A larger, spreading tree.
• Fruit : Known for its large, flavorful olives, often used for table olives as well as oil.
• Growth Rate : Moderate.
• Climate Suitability : Prefers warm climates and may not tolerate extreme cold as well as some other varieties.

• Origin : Tuscany, Italy.
• Size : Medium to large, with a spreading canopy.
• Fruit : Highly regarded for its superior quality oil, with a fruity flavor.
• Growth Rate : Moderate to fast.
• Climate Suitability : Adapts well to various climates, including cooler regions.

Other Factors to Consider

• Soil Type : Olive trees prefer well-drained soil. Even if you choose a hardy variety, poor drainage can lead to root rot.
• Space and Size : Consider the mature size of the tree. Some varieties, like ‘Arbequina’, are more compact, making them suitable for smaller gardens or containers.
• Pollination : Most olive trees are self-fertile, but having more than one variety can improve pollination and increase yield.
• Purpose of Olives : Are you growing olives for oil or as table olives? Different varieties are better suited to different uses. For instance, ‘Frantoio’ is excellent for oil, while ‘Manzanillo’ is great for eating.

Olive trees require a spot that receives at least six hours of direct sunlight daily. They prefer well-draining soil; standing water can lead to root rot. If your soil is heavy or clay-like, consider planting your tree in a raised bed or container to improve drainage.

The Importance of Sunlight

• Olive trees are sun-loving plants. They require at least six hours of direct sunlight daily to thrive. This sunlight is crucial for photosynthesis, which helps the tree produce energy for growth and fruit production.
• When choosing a location, observe the area during different times of the day to ensure that the chosen spot consistently receives ample sunlight.

Understanding Soil Requirements

• Olive trees prefer well-draining soil. This is because their roots are prone to rot in waterlogged conditions. Good drainage ensures that excess water moves away from the root zone.
• If your garden soil is heavy or predominantly clay, it might retain more moisture than is ideal for an olive tree. In such cases, consider altering the soil structure or choosing a different planting method.

Amending Heavy or Clay-Like Soil

• To improve drainage in heavy soils, mix in organic matter such as compost or well-rotted manure. This addition will help break up dense soil particles, enhancing water drainage and aeration.
• Consider adding sand or gravel to the soil. These coarse materials create larger spaces in the soil, allowing water to drain more effectively.

Alternative Planting Methods

• Raised Beds: If your soil conditions are not ideal, planting olive trees in raised beds is an excellent alternative. Raised beds offer better drainage and allow you to control the soil composition.
• Containers: Growing olive trees in containers is another viable option, especially if you have limited space or unsuitable ground soil. Containers provide excellent drainage and the flexibility to move the tree if needed. Ensure the container is large enough (typically at least 18-24 inches in diameter) and has drainage holes.

• Why Timing Matters : The timing of planting is crucial for the establishment of the olive tree. Planting during extreme temperatures (hot or cold) can stress the young tree.
• Spring Planting : In spring, the soil is warming up, which encourages root growth. There’s also typically more natural rainfall, aiding the tree’s establishment.
• Fall Planting : Early fall planting allows the tree to establish roots before the winter, taking advantage of the warm soil and cooler air, which is less stressful for the tree.

Preparing the Site

• Site Selection : Ensure the location gets full sunlight and has good drainage.
• Hole Preparation : The hole’s size is critical. It needs to be twice as wide as the root ball to give the roots room to expand. However, it shouldn’t be deeper than the root ball, to prevent the tree from settling too low, which can cause water to pool around the base and lead to root rot.
• Soil Considerations : If your soil is poor, mix in some compost or well-rotted manure to the excavated soil. This will improve nutrient content and drainage.

• Removing from Container : Be gentle to minimize root disturbance. If the tree is root-bound (roots tightly wound), lightly score the sides of the root ball to encourage outward growth.
• Positioning the Tree : Carefully place the tree in the center of the hole. It’s important to keep the tree straight and to ensure that the top of the root ball is level with the surrounding ground.

Backfilling

• Technique : Backfill with the excavated soil, mixing in organic matter if needed. While filling, gently tamp the soil to eliminate air pockets, which can dry out roots.
• Avoid Over-Compaction : Overly compact soil can make water penetration difficult and hinder root growth. The goal is to have the soil firm enough to support the tree but not so hard that roots can’t expand.

Olive trees are drought-tolerant once established, but getting the watering right is crucial, especially in the early years. The key is to provide enough water to support the growth while avoiding excess moisture that can lead to root rot.

• Young Trees : For the first year or so, water your olive tree weekly, ensuring the soil is moist but not waterlogged.
• Established Trees : Reduce watering frequency as the tree matures. Generally, deep watering once a month is sufficient, but this can vary depending on your climate and soil type. During hot and dry spells, you might need to water more frequently.
• Drainage : Ensure good drainage around your tree. If you notice water pooling around the base after watering, consider improving the soil drainage or relocating the tree.

Fertilizing

Nutrition is vital for the growth and fruit production of your olive tree.

• Type of Fertilizer : A balanced, slow-release fertilizer is ideal. Look for one with equal parts nitrogen, phosphorus, and potassium (N-P-K).
• When to Fertilize : Apply fertilizer in early spring as new growth begins. This helps the tree prepare for the growing season.
• Method : Spread the fertilizer evenly around the base of the tree, extending out to the drip line (the outermost circumference of the tree’s canopy). Avoid placing fertilizer too close to the trunk.
• Additional Nutrients : Depending on your soil quality, your tree might benefit from additional iron or magnesium. Soil tests can guide specific nutrient additions.

Pruning is essential for maintaining the health and productivity of your olive tree.

• Timing : Late spring, after the risk of frost has passed, is the best time to prune.
• Objective : Focus on shaping the tree, allowing light penetration, and air circulation. Remove any suckers, dead or diseased wood, and any branches that are crossing or rubbing against each other.
• Technique : Make clean cuts with sharp pruning tools. For larger branches, use a saw to avoid tearing the bark.
• Moderation : Be careful not to over-prune, as this can reduce fruit yield. Generally, removing about 10-30% of the total canopy each year is recommended.

Protecting from Frost

Young olive trees are more susceptible to frost damage than mature ones.

• Frost Blankets : Use frost blankets or burlap to cover your tree during cold nights. Ensure the cover reaches the ground to trap heat.
• Location : Plant your tree in a sheltered location if you expect regular frost. Areas near walls or buildings can provide additional warmth.
• Mulching : Apply a layer of mulch around the base of the tree to insulate the roots, but keep the mulch away from the trunk to prevent moisture buildup.
• Watering Before Frost : Interestingly, watering the ground around the tree before a frost can help, as moist soil retains heat better than dry soil.

The harvesting of olives is a crucial aspect of olive cultivation, determining not just the yield but also the flavor profile of both the fruit and the olive oil produced. Understanding when and how to harvest can enhance both the quality and quantity of your harvest.

Knowing When to Harvest

Olive trees, depending on their variety, begin to bear fruit typically between 3 to 6 years after planting. The timing of harvest is critical and varies depending on what the olives are being used for

• Green olives are harvested while they are unripe, usually in late summer to early fall. These have a firmer texture and a more bitter, vibrant flavor.
• Turning olives are picked during the color-changing phase, when the olives transition from green to a reddish or purple color. These offer a balanced flavor.
• Black olives are fully ripe and are harvested in late fall. They tend to be softer and have a milder, sweeter flavor compared to green olives.
• For Oil : If you’re harvesting for olive oil, the timing can affect the oil’s flavor and acidity. A mix of green and slightly riper olives often produces oil with a balanced flavor and lower acidity.

Harvesting Methods

There are various methods for harvesting olives, ranging from traditional to more modern techniques:

• Hand-Picking : This labor-intensive method is gentle on the trees and fruit, ideal for producing high-quality olives for eating. It involves picking olives by hand, one by one.
• Using Poles or Rakes : Using long poles or handheld rakes to gently beat or comb the branches, causing the olives to fall onto nets placed under the trees. This method is faster than hand-picking but can be more damaging to the fruit and tree.
• Mechanical Harvesters : Large scale operations often use mechanical harvesters that shake the trees or branches, causing the olives to fall. This method is efficient but can be harsh on the trees and is not suitable for all varieties.

Post-Harvest Handling

• After harvesting, it’s essential to process olives promptly, especially if they are to be used for oil, as delays can lead to fermentation and a decline in quality.

Curing Olives

Raw olives are inedible due to their natural bitterness. Curing is the process of removing this bitterness, and there are several methods:

• Water Curing : Soaking olives in water that is changed daily over a course of several days or weeks.
• Brine Curing : Submerging olives in a saltwater solution for a few weeks to several months, depending on the olive size and type.
• Dry Curing : Coating olives in salt to draw out bitterness and moisture, typically used for ripe, black olives.
• Lye Curing : Using a lye solution to rapidly cure the olives, a method often used commercially.

Planting an olive tree can be a rewarding endeavor. With proper care, your tree will not only beautify your landscape but also provide a bountiful harvest of olives. Embrace the process and enjoy the journey of growing this symbol of peace and prosperity in your own backyard.

FAQs (Frequently Asked Questions)

• What is the best time to plant an olive tree? The optimal time to plant an olive tree is in the spring or early fall, which allows the tree to establish roots in moderate temperatures before extreme weather conditions.
• How much sun does an olive tree need? Olive trees require full sun, meaning at least 6 hours of direct sunlight daily, to thrive and produce fruit effectively.
• What type of soil is best for olive trees? Well-draining soil with a slightly acidic to neutral pH (around 6 to 7) is ideal for olive trees. They don’t do well in heavy, clay-rich or overly soggy soils.
• How do I prepare the soil for planting an olive tree? Amend heavy soils with sand or gravel to improve drainage. It’s also advisable to test the soil’s pH and adjust it if necessary.
• How deep should I plant an olive tree? The hole should be just deep enough to accommodate the root ball. It’s important not to plant the tree too deep; the top of the root ball should be level with the surrounding soil.
• How often should I water a newly planted olive tree? Newly planted olive trees should be watered regularly to maintain moist, but not waterlogged, soil. Once established, they are quite drought-tolerant and need less frequent watering.
• Do I need to fertilize my olive tree? Yes, feeding your olive tree with a balanced, slow-release fertilizer in the early spring can promote healthy growth. Avoid over-fertilizing, especially with nitrogen-rich fertilizers.
• How do I prune an olive tree? Prune in late winter or early spring. Remove dead or diseased branches, and thin out dense growth to allow light into the canopy. If you’re growing the tree for fruit, strategic pruning is essential for good yields.
• How long will it take for my olive tree to bear fruit? Olive trees typically begin to bear fruit within 3-5 years of planting, but full fruit production can take up to 5-12 years, depending on the variety and growing conditions.
• Can I grow an olive tree in a pot? Yes, olive trees can be grown in large pots or containers, provided they have sufficient drainage. Container-grown trees will need more frequent watering and repotting every couple of years.

For more expert gardening advice, explore our  guides , discover top recommendations in our  best section , and delve into in-depth  product reviews  in our review section.

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Fact sheet: olive trees – more than just a tree in palestine.

Olive trees carry more than an economic significance in the lives of Palestinians. They are not just like any another trees, they are symbolic of Palestinians’ attachment to their land. Because the trees are draught-resistant and grow under poor soil conditions, they represent Palestinian resistance and resilience. The fact that olive trees live and bear fruit for thousands of years is parallel to Palestinian history and continuity on the land. Palestinians are proud of their olive trees; they take care of them with care and appreciation. Palestine has some of the world’s oldest olive trees, dating back to 4,000 years. Some families have trees that have been passed down to them for generations and the olive harvest season in October bears a socio-cultural meaning where families come together to harvest olive trees bearing in mind that their forefathers and mothers had tended to the same trees several years ago.

In addition to their symbolic meaning, olives are a main source of income for around 80,000 Palestinian families. According to UN figures, around 48% of the agricultural land in the West Bank and Gaza is planted with olive trees. Olive trees account for 70% of fruit production in Palestine and contribute around 14% to the Palestinian economy. 93% of the olive harvest is used for olive oil production while the rest is used for olive soap, table olives and pickles. Much of the olive production is for local consumption with a small amount of olives being exported primarily to Jordan. With the growing interest in organic food and fair trade, Palestinian olives are now also reaching European and North American markets.

Challenges in maintaining olives

Palestinian farmers face several challenges in maintaining their olive trees before they are harvested. If the land where the olives are planted lies in Area C, 60% of the West Bank, which according to Oslo is under full Israeli control, the farmers need permits from Israeli authorities to access their land and to tend to their trees. The same regulation applies to those farmers whose lands are in the “seam zone” i.e the area between the Green Line and the Separation Wall.

In Gaza, the security “buffer-zone” extends well beyond 600 meters from the Gaza-Israel Green Line, taking up 30% of agricultural land. Further, farmers are not able to access the land 1.5 km into Gaza from the security line because of Israeli shelling, shooting and incursions. OCHA figures indicate that 7,300 dunums of land with olives along the fence have been destroyed during Israeli military operations. Further, Palestinian famers in Gaza are discouraged from replanting their olive trees for fear that they would be destroyed in Israeli sieges and for fear that they might be hit by “warning shots”.

But the permit system is in most cases rather arbitrary. There are no clear lists of requirements the Palestinian applicants must fulfill to get the permit. After having shown legal documents of ownership and passing the “security“ check, the permit might be issued to only the person under whose name the land is registered with no one else from the family allowed to access the land. This becomes a problem because land ownership belongs to the whole family even if the land registration is under the name of one of the family members. In addition, limiting the number of people who can work the land also affects agricultural efficiency which in turn affects the olive produce and economic gains from it later on.

Further, when permits are issued, they are often issued for a short term and need to be renewed, each time with no guarantee that it will be renewed. According to UN sources, 42% of applications for permits to access olive groves behind the Wall in 2011 and 39% in 2010 were denied. If a family member is politically active and or has been detained (during demonstrations for example) everyone in the family might be denied permits. Hence, the permit system is used to coerce Palestinians into forfeiting resistance to the Occupation.

When permits are issued especially to those whose lands are in the ‘seam zone’ or near settlements, the farmers have to pass through agricultural checkpoints to access their trees. These checkpoints are often opened at certain times a year and for a few hours a day, limiting Palestinian farmers from working as much as they see fit which later also determines their produce. In general, because uncultivated land is more likely to be confiscated by Israel as state land and because the permit system and the agricultural checkpoints regulate the kind and amount of fertilizers, tractors, vehicles and other materials, some farmers have been forced to revert to planting olive trees and relying on them for their income even if their land is conducive for other types of fruit. Since olive trees can survive even when not well taken care, they serve as a way of retaining land ownership and provide the main source of income for Palestinian farmers.

• Settler attacks, economic costs and lack of mechanisms for legal redress

Another growing challenge facing Palestinian farmers is attacks by settlers. This year (2012), UNOCHA reported that 7,500 olive trees were destroyed between January and mid-October. Attacks by settlers have increased by 39% from the year 2010 to 2011 and by 315% from 2007 – 2011. And these attacks spike up during the olive harvest season in which Palestinian farmers become targets as they harvest their olives. While some of these attacks are committed under the name of “price tag” i.e punishment of Palestinians for Israeli court ordered and enforced removal of outposts, most of the attacks including price tags emanate from structural hatred, racism towards Palestinians and Zionist ideological claims to the land. In the words of the head of the “settlers’ struggle headquarters” in Yitzhar settlement (as recorded by B’Tselem), attacks on Palestinians is "a display of good citizenship that was intended to help the police enforce the planning and building laws in the area on Palestinians."

Overall, around 2.5 million trees, one-third of which are olive trees, are believed to have been uprooted since 1967. Estimating the average annual productivity of an olive tree to be 70 kilos and the price of olive seeds 1.103 USD/Kilo, Applied Research Institute Jerusalem estimates that the Palestinian economy has lost about 55,133,602 USD since 1967 to 2009.

• Lack of complaint system

The majority of the complaints against such attacks are not seriously investigated by the police or the army. Only one out of the 162 complaints regarding settler attacks on Palestinian olive trees reported by Yesh Din, an Israeli NGO since 2005 has led to indictment of a suspect. Israeli human rights group B’Tselem and other groups have also reported that Israeli security forces are not deployed in advance to protect Palestinians in areas of threat and neither do they protect Palestinians when settlers attack. In fact, often times, Israeli soldiers put more restraint on Palestinians rather than settlers when confrontations arise.

http://www.middleeastmonitor.com/resources/fact- ... http://www.ochaopt.org/documents/ocha_opt_olive_ha ... http://www.aljazeera.com/indepth ... http://www.aljazeera.com/ind ... http://www.jai-pal.org/ ... http://www.thejerusalemfund.org/ht/a/GetDocument ... http://www.mne.gov.ps/pdf/Economiccostsofoc ...

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The Olive Trees

• Vincent van Gogh

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Between May 1889 and May 1890, Vincent painted olive trees at least 15 times. Some of the artist’s famous olive tree paintings are Olive Trees in a Mountainous Landscape, Olive Grove, Olive Grove II, and Olive Trees with Yellow Sky and Sun.

In these paintings, he showed how man interacts with nature and the effects that the interactions have. The Olive Trees with Yellow Sky and Sun, inspired by Paul Gaugin, piques viewers’ interest with the beautifully combined colours on the oil and canvas painting.

The painting consists of three major colours: yellow, green, and solid brown, with blue traces on the ground. Vincent shows the sun brightly shining in a beautiful yellow colour, the trees colourfully green, and the browning grass or vegetation below the trees. Closely looking at the trees, the audience notices the shadows cast on the ground by the enormous trees.

Most interpretations state that the painting showed a theme of Jesus in the garden of Gethsemane when he faced betrayal by Judas. However, the profound painter eliminates any reference to Jesus in his paintings. He completed The Olive Trees with Yellow Sky and Sun during his last year of life, 1889, and left a huge art piece.

In a letter he sent to his brother Theo, Vincent revealed the connection between the olive groves and the painting series. The Starry Night, Olive Grove, and The Olive Trees with Yellow Sky and Sun are interconnected. In the letter, he disclosed that all of them are from and painted from memory and are not photographically reproduced.

With his great mastery of colour patterns and natural rhythms, Vincent painted the world from his perspective; he showed the viewers what his life was on the canvas. In his life confined life at the asylum, Van Gogh showcased over 150 oil and canvas art. As such, this was his most productive time before his breakdowns became more rampant, and his condition worsened. This particular set of paintings showed an optimistic yet haunting and hopeful effect. He explained what he feels like to the audience.

Most of the olive trees paintings were in landscape and on vibrant colour palettes. The Olive Trees with Yellow Sky and Sun shows a bright sun shining upon nature. The sun has an orange halo that casts a light blue and black shadow on the vegetation. In the far background, the mountain peaks are visible and painted in blue, just like the shadows. It is a sign of hope that Van Gogh left for art lovers.

Article Author

Tom Gurney in an art history expert. He received a BSc (Hons) degree from Salford University, UK, and has also studied famous artists and art movements for over 20 years. Tom has also published a number of books related to art history and continues to contribute to a number of different art websites. You can read more on Tom Gurney here.

• Frontiers in Plant Science
• Crop and Product Physiology
• Research Topics

Olive Science

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About this Research Topic

Olive is one of the most cultivated fruit tree species, covering more than 10 million hectares. Olive is cultivated to produce both table olives and oil, with the latter being the main production. The consumption of both olives and oil has doubled in the last thirty years, due to the spread of the ...

Keywords : olive, tree physiology, fruit and oil quality, abiotic and biotic stress, environmental factors

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How to grow olives

• BBC Gardeners' World Magazine

Olive trees are easy to grow in the UK but encouraging them to fruit is a different matter. Find out more, in our Grow Guide.

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This article has been checked for horticultural accuracy by Oliver Parsons .

The olive tree, Olea europaea , is a classic Mediterranean tree that we might associate more with holidays than our own back garden. However, being slow-growing and usually only reaching a modest size, it makes a good garden tree in the UK. They can be grown in borders but make good trees for pots , too. There are now many cultivars that tolerate cooler temperatures to choose from, although a sunny, sheltered location will get the best results. You might even be lucky enough to get your own crop of olives – perhaps not enough for a bottle of olive oil, but certainly enough to cure and serve up as an appetiser.

Grow olives in free-draining soil or compost in a sheltered, sunny site. There's no need to feed olives growing in the ground but they may need protection from frost in winter.

Where to grow olive trees

Olives are Mediterranean plants so thrive in conditions closest to the hot, dry climate of their native habitat. Choose the sunniest and most sheltered spot available – a south-facing spot with a brick wall behind it will work well.

How to plant olive trees

If you’re growing your olive tree in a border, dig a hole and add mycorrhizal fungi to help the tree establish quickly. If you have heavy soil then add plenty of grit to aid drainage. If growing in a container or raised bed, prepare a soil-based mix of compost and grit, with added some organic matter.

More like this

Most olive trees are supplied pot-grown, so they can be planted at any time of the year, unless the soil is frozen.

It’s possible to grow an olive tree from seed, but this is a long process and when grown, your plant will revert to a wild variety, rather than its parent cultivar. You need heat to get seeds to germinate – sow undercover in a propagator in spring.

Olive trees in pots

Olive trees lend themselves well to growing in pots as they do best in free-draining soils and can benefit from being moved to a porch or other sheltered spot for winter. Terracotta pots are more breathable than plastic pots and therefore create drier soil conditions, they can also look stylish and work perfectly for a Mediterranean-style patio display.

When choosing an olive tree to plant in a pot, opt for a compact variety so it won't outgrow its space. Use a loam-based peat-free compost such as John Innes No.3, and add a few handfuls of horticultural grit to aid drainage.

You'll still need to water and feed your olive tree regularly through the warmer months, as the roots don't have as much space to search for water and nutrients. Avoid letting the compost dry out completely, and use a liquid seaweed feed once a fortnight from April to September to keep it growing well. However, you mustn't let the pot get waterlogged, particularly in the winter as the plant won't be in active growth and the water is likely to freeze around the roots. Standing the pot on pot feet will allow the water to drain freely.

When planting, use a slightly larger pot than the one your olive tree came in, and ideally plant in spring so it has the whole season to settle in before winter. You may need to move your potted olive tree to a sheltered spot for winter, or use horticultural fleece to wrap around the canopy to protect it from frost.

Olive tree care

Olive trees are fairly drought tolerant, but if they're growing in pots they need to be kept well watered. Dry spells during early spring can affect flowering and fruiting, so if you want to grow a crop of olives be particularly watchful. Potted plants also need feeding regularly with a liquid feed every two weeks during the growing season.

In severe winter weather, you may need to protect border-grown trees with horticultural fleece. A winter mulch around the base of the tree also helps in this regard, while also boosting soil nutrients and helping to regulate soil moisture through the year. For trees in pots, wrap the container with a layer of bubble wrap to protect the roots from frost, and the upper parts of the plant with breathable horticultural fleece.

Olive trees are slow growing and do not need much pruning other than to keep to the desired size and shape. Prune in late spring to midsummer to remove dead, diseased or dying branches. Thin branches to allow more light into the centre. Although evergreen, olives do shed leaves, mostly in late spring as older leaves make way for new growth.

Harvesting and storing olives

A new tree will take around four years to bear fruit, and if conditions are not warm and sunny enough, it may not do so at all. However if yours does, it's best to harvest the olives in late autumn.

If you've ever eaten an olive straight from the tree you will understand why they need to be cured – they are extremely bitter to taste. To make them palatable, soak them in a brine solution for up to six weeks, changing the water regularly.

Olive trees: problem solving

Olives can be affected by extremely cold weather, below -10°C. This can cause damage to the foliage and bark. However, plants should recover, although they might suffer in terms of fruit production the following season.

Extreme wet can cause leaves to drop and may weaken the tree. This can allow other diseases, such as verticillium wilt or phytopthora root rot, to take hold. Olive trees can also be affected by honey fungus , so don’t plant in areas where this disease has been found.

Olive scab is a fungal disease that causes spots on the leaves, excessive loss of foliage and poor fruit production.

How to propagate olive trees

Olive trees can be propagated by taking semi-ripe cuttings in summer or hardwood cuttings in winter.

Advice on growing olives

• Choose between a traditional, natural-looking olive tree or one that's been shaped as a standard into a lollipop tree
• As olive trees are slow growing, it can be worth buying the largest size tree you can afford
• Olives are host to the disease Xylella fastidiosa , which has been decimating continental European olive plantations, so only buy olive trees from a reputable supplier, with an appropriate Plant Passport
• Check for signs of other pests or diseases before planting

Where to buy olives

• Thompson & Morgan

Olive tree varieties to try

Olea europaea ‘Arbequina’ – a Spanish variety from Catalonia, small but vigorous, with good tolerance of frost and poorer soils.

• Buy Olea europaea ‘Arbequina’ from Provender Nurseries

Olea europaea ‘Cipressino’ – a southern Italian variety from Puglia, this has an upright, compact growth habit, making it a good choice for smaller gardens or for growing in pots. It is hardy and good for coastal gardens.

• Buy Olea europaea ‘Cipressino’ from Garden Plants Online

Olea europaea ‘Frantoio’ – a classic Tuscan olive tree, self-fertile and the source of many bottles of olive oil. Easy to grow in the UK and a good choice if you want a reliably productive tree

• Buy Olea europaea ‘Frantoio’ from Cedar Nursery

Olea europaea ‘Leccino’ – a reliable Italian variety that does very well in the UK climate.

• Buy Olea europaea ‘Leccino’ from Cedar Nursery

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Heilbrunn Timeline of Art History Essays

Vincent van gogh (1853–1890).

Road in Etten

Vincent van Gogh

Nursery on Schenkweg

Self-Portrait with a Straw Hat (obverse: The Potato Peeler)

The Potato Peeler (reverse: Self-Portrait with a Straw Hat)

Street in Saintes-Maries-de-la-Mer

The Flowering Orchard

Peasant Woman Cooking by a Fireplace

Wheat Field with Cypresses

Corridor in the Asylum

L'Arlésienne: Madame Joseph-Michel Ginoux (Marie Julien, 1848–1911)

La Berceuse (Woman Rocking a Cradle; Augustine-Alix Pellicot Roulin, 1851–1930)

Olive Trees

First Steps, after Millet

Department of European Paintings , The Metropolitan Museum of Art

October 2004 (originally published) March 2010 (last revised)

Vincent van Gogh, the eldest son of a Dutch Reformed minister and a bookseller’s daughter, pursued various vocations, including that of an art dealer and clergyman, before deciding to become an artist at the age of twenty-seven. Over the course of his decade-long career (1880–90), he produced nearly 900 paintings and more than 1,100 works on paper. Ironically, in 1890, he modestly assessed his artistic legacy as of “very secondary” importance.

Largely self-taught, Van Gogh gained his footing as an artist by zealously copying prints and studying nineteenth-century drawing manuals and lesson books, such as Charles Bargue’s Exercises au fusain and cours de dessin . He felt that it was necessary to master black and white before working with color, and first concentrated on learning the rudiments of figure drawing and rendering landscapes in correct perspective. In 1882, he moved from his parents’ home in Etten to the Hague, where he received some formal instruction from his cousin, Anton Mauve, a leading Hague School artist. That same year, he executed his first independent works in watercolor and ventured into oil painting; he also enjoyed his first earnings as an artist: his uncle, the art dealer Cornelis Marinus van Gogh, commissioned two sets of drawings of Hague townscapes for which Van Gogh chose to depict such everyday sites as views of the railway station, gasworks, and nursery gardens ( 1972.118.281 ).

Van Gogh’s admiration for the Barbizon artists, in particular Jean-François Millet, influenced his decision to paint rural life. In the winter of 1884–85, while living with his parents in Nuenen, he painted more than forty studies of peasant heads, which culminated in his first multifigured, large-scale composition ( The Potato Eaters , Van Gogh Museum, Amsterdam); in this gritty portrayal of a peasant family at mealtime, Van Gogh wrote that he sought to express that they “have tilled the earth themselves with the same hands they are putting in the dish.” Its dark palette and coarse application of paint typify works from the artist’s Nuenen period ( 67.187.70b ;  1984.393 ).

Interested in honing his skills as a figure painter, Van Gogh left the Netherlands in late 1885 to study at the Antwerp Academy in Belgium. Three months later, he departed for Paris, where he lived with his brother Theo, an art dealer with the firm of Boussod, Valadon et Cie, and for a time attended classes at Fernand Cormon’s studio. Van Gogh’s style underwent a major transformation during his two-year stay in Paris (February 1886–February 1888). There he saw the work of the Impressionists first-hand and also witnessed the latest innovations by the Neo-Impressionists Georges Seurat and Paul Signac. In response, Van Gogh lightened his palette and experimented with the broken brushstrokes of the Impressionists as well as the pointillist touch of the Neo-Impressionists, as evidenced in the handling of his Self-Portrait with a Straw Hat ( 67.187.70a ), which was painted in the summer of 1887 on the reverse of an earlier peasant study ( 67.187.70b ). In Paris, he executed more than twenty self-portraits that reflect his ongoing exploration of complementary color contrasts and a bolder style.

In February 1888, Van Gogh departed Paris for the south of France, hoping to establish a community of artists in Arles. Captivated by the clarity of light and the vibrant colors of the Provençal spring, Van Gogh produced fourteen paintings of orchards in less than a month, painting outdoors and varying his style and technique. The composition and calligraphic handling of The Flowering Orchard ( 56.13 ) suggest the influence of Japanese prints , which Van Gogh collected. The artist’s debt to ukiyo-e prints is also apparent in the reed pen drawings he made in Arles, distinguished by their great verve and linear invention ( 48.190.1 ). In August, he painted the still lifes Oleanders ( 62.24 ) and Shoes ( 1992.374 ); each work resonates with the artist’s personal symbolism. For Van Gogh, oleanders were joyous and life-affirming (much like the sunflower); he reinforced their significance with the compositional prominence accorded to Émile Zola’s 1884 novel La joie de vivre . The still life of unlaced shoes, which Van Gogh had apparently hung in Paul Gauguin ‘s “yellow room” at Arles, suggested, to Gauguin, the artist himself—he saw them as emblematic of Van Gogh’s itinerant existence.

Gauguin joined Van Gogh in Arles in October and abruptly departed in late December 1888, a move precipitated by Van Gogh’s breakdown, during which he cut off part of his left ear with a razor. Upon his return from the hospital in January, he resumed working on a portrait of the wife of the postmaster Joseph Roulin; although he painted all the members of the Roulin family, Van Gogh produced five versions of Madame Roulin as La Berceuse , shown holding the rope that rocks her newborn daughter’s cradle ( 1996.435 ). He envisioned her portrait as the central panel of a triptych, flanked by paintings of sunflowers. For Van Gogh, her image transcended portraiture, symbolically resonating as a modern Madonna; of its palette, which ranges from ocher to vermilion and malachite, Van Gogh expressed his desire that it “sing a lullaby with color,” underscoring the expressive role of color in his art.

Fearing another breakdown, Van Gogh voluntarily entered the asylum at nearby Saint-Rémy in May 1889, where, over the course of the next year, he painted some 150 canvases. His initial confinement to the grounds of the hospital is reflected in his imagery, from his depictions of its corridors ( 48.190.2 ) to the irises and lilacs of its walled garden, visible from the window of the spare room he was allotted to use as a studio. Venturing beyond the grounds of the hospital, he painted the surrounding countryside, devoting series to its olive groves ( 1998.325.1 ) and cypresses, which he saw as characteristic of Provence. In June, he produced two paintings of cypresses, rendered in thick, impastoed layers of paint ( 49.30 ; Cypresses , Kröller-Müller Museum, Otterlo), likening the form of a cypress to an Egyptian obelisk in a letter to his brother Theo. These evocative trees figure prominently in a landscape, produced the same month ( 1993.132 ). Van Gogh regarded this work, with its sun-drenched wheat field undulating in the wind, as one of his “best” summer canvases. At Saint-Rémy, he also painted copies of works by such artists as Delacroix, Rembrandt , and Millet, using black-and-white photographs and prints. In fall and winter 1889–90, he executed twenty-one copies after Millet ( 64.165.2 ); he described his copies as “interpretations” or “translations,” comparing his role as an artist to that of a musician playing music written by another composer. During his last week at the asylum, he extended his repertoire of still life by painting four bouquets of Irises ( 58.187 ) and Roses ( 1993.400.5 ) as a final series comparable to the sunflower decoration he made earlier in Arles.

After a year at Saint-Rémy, Van Gogh left, in May 1890, to settle in Auvers-sur-Oise, where he was near his brother Theo in Paris and under the care of Dr. Paul Gachet, a homeopathic physician and amateur painter. In just over two months, Van Gogh averaged a painting a day; however, on July 27, 1890, he shot himself in the chest in a wheat field; he died two days later. His artistic legacy is preserved in the paintings and drawings he left behind, as well as in his voluminous correspondence, primarily with Theo, which lays bare his working methods and artistic intentions and serves as a reminder of his brother’s pivotal role as a mainstay of support throughout his career.

By the time of his death in 1890, Van Gogh’s work had begun to attract critical attention. His paintings were featured at the Salon des Indépendants in Paris between 1888 and 1890 and with Les XX in Brussels in 1890. As Gauguin wrote to him, his recent works, on view at the Indépendants in Paris, were regarded by many artists as “the most remarkable” in the show; and one of his paintings sold from the 1890 exhibition in Brussels. In January 1890, the critic Albert Aurier published the first full-length article on Van Gogh, aligning his art with the nascent Symbolist movement and highlighting the originality and intensity of his artistic vision. By the outbreak of World War I, with the discovery of his genius by the Fauves and German Expressionists, Vincent van Gogh had already come to be regarded as a vanguard figure in the history of modern art.

Department of European Paintings. “Vincent van Gogh (1853–1890).” In Heilbrunn Timeline of Art History . New York: The Metropolitan Museum of Art, 2000–. http://www.metmuseum.org/toah/hd/gogh/hd_gogh.htm (originally published October 2004, last revised March 2010)

Further Reading

Brooks, David. Vincent van Gogh: The Complete Works . CD-ROM. Sharon, Mass.: Barewalls Publications, 2002.

Dorn, Roland, et al. Van Gogh Face to Face: The Portraits . New York: Thames & Hudson, 2000.

Druick, Douglas W., et al. Van Gogh and Gauguin: The Studio of the South . Exhibition catalogue. New York: Thames & Hudson, 2001.

Ives, Colta, et al. Vincent van Gogh: The Drawings . Exhibition catalogue. New York: Metropolitan Museum of Art, 2005. See on MetPublications

Kendall, Richard. Van Gogh's Van Gogh's: Masterpieces from the Van Gogh Museum, Amsterdam . Washington, D.C.: National Gallery of Art, 1998.

The Complete Letters of Vincent van Gogh . 3 vols. Boston: Bullfinch Press, 2000.

Pickvance, Ronald. Van Gogh in Arles . New York: Metropolitan Museum of Art, 1984. See on MetPublications

Pickvance, Ronald. Van Gogh in Saint-Rémy and Auvers . New York: Metropolitan Museum of Art, 1986. See on MetPublications

Selected and edited by Ronald de Leeuw. The Letters of Vincent van Gogh . London: Penguin, 2006.

Stein, Susan Alyson, ed. Van Gogh: A Retrospective . New York: New Line Books, 2006.

Stolwijk, Chris, and Richard Thomson. Theo van Gogh . Amsterdam: Van Gogh Museum, 1999.

Vincent van Gogh: The Letters. Online resource.

Additional Essays by Department of European Paintings

• Department of European Paintings. “ The Rediscovery of Classical Antiquity .” (October 2002)
• Department of European Paintings. “ Architecture in Renaissance Italy .” (October 2002)
• Department of European Paintings. “ Titian (ca. 1485/90?–1576) .” (October 2003)
• Department of European Paintings. “ The Papacy and the Vatican Palace .” (October 2002)

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List of Rulers

• List of Rulers of Europe
• Central Europe and Low Countries, 1800–1900 A.D.
• France, 1800–1900 A.D.
• 19th Century A.D.
• 20th Century A.D.
• Agriculture
• Barbizon School
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• Floral Motif
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Artist or Maker

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