Cannabis is an
annual,
dioecious,
floweringherb. The
leaves are
palmately compound or digitate, with
serrateleaflets.[11] The first pair of leaves usually have a single leaflet, the number gradually increasing up to a maximum of about thirteen leaflets per leaf (usually seven or nine), depending on
variety and growing conditions. At the top of a flowering plant, this number again diminishes to a single leaflet per leaf. The lower leaf pairs usually occur in an opposite
leaf arrangement and the upper leaf pairs in an alternate arrangement on the main stem of a mature plant.
The leaves have a peculiar and diagnostic
venation pattern (which varies slightly among varieties) that allows for easy identification of cannabis leaves from unrelated species with similar leaves. As is common in serrated leaves, each serration has a central vein extending to its tip, but in cannabis this originates from lower down the central vein of the leaflet, typically opposite to the position of the second notch down. This means that on its way from the midrib of the leaflet to the point of the serration, the vein serving the tip of the serration passes close by the intervening notch. Sometimes the vein will pass tangentially to the notch, but often will pass by at a small distance; when the latter happens a spur vein (or occasionally two) branches off and joins the leaf margin at the deepest point of the notch. Tiny samples of Cannabis also can be identified with precision by microscopic examination of leaf cells and similar features, requiring special equipment and expertise.[12]
Reproduction
All known
strains of Cannabis are
wind-pollinated[13] and the fruit is an
achene.[14] Most strains of Cannabis are
short day plants,[13] with the possible exception of C. sativa subsp. sativa var. spontanea (= C. ruderalis), which is commonly described as "auto-flowering" and may be
day-neutral.
Cannabis is predominantly
dioecious,[13][15] having
imperfectflowers, with
staminate "male" and
pistillate "female" flowers occurring on separate plants.[16] "At a very early period the Chinese recognized the Cannabis plant as dioecious",[17] and the (c. 3rd century BCE) Erya dictionary defined xi枲 "male Cannabis" and fu莩 (or ju苴) "female Cannabis".[18] Male flowers are normally borne on loose
panicles, and female flowers are borne on
racemes.[19]
Many
monoecious varieties have also been described,[20] in which individual plants bear both male and female flowers.[21] (Although monoecious plants are often referred to as "hermaphrodites", true hermaphrodites – which are less common in Cannabis – bear staminate and pistillate structures together on individual flowers, whereas monoecious plants bear male and female flowers at different locations on the same plant.)
Subdioecy (the occurrence of monoecious individuals and dioecious individuals within the same population) is widespread.[22][23][24] Many populations have been described as sexually labile.[25][26][27]
As a result of intensive selection in
cultivation, Cannabis exhibits many sexual phenotypes that can be described in terms of the ratio of female to male flowers occurring in the individual, or typical in the cultivar.[28] Dioecious varieties are preferred for drug production, where the fruits (produced by female flowers) are used. Dioecious varieties are also preferred for textile fiber production, whereas monoecious varieties are preferred for pulp and paper production. It has been suggested that the presence of monoecy can be used to differentiate licit crops of monoecious hemp from illicit drug crops,[22] but sativa strains often produce monoecious individuals, which is possibly as a result of
inbreeding.
Cannabis has been described as having one of the most complicated mechanisms of
sex determination among the dioecious plants.[28] Many models have been proposed to explain sex determination in Cannabis.
Based on studies of sex reversal in
hemp, it was first reported by K. Hirata in 1924 that an
XY sex-determination system is present.[26] At the time, the XY system was the only known system of sex determination. The
X:A system was first described in Drosophila spp in 1925.[29] Soon thereafter, Schaffner disputed Hirata's interpretation,[30] and published results from his own studies of sex reversal in hemp, concluding that an X:A system was in use and that furthermore sex was strongly influenced by environmental conditions.[27]
Since then, many different types of sex determination systems have been discovered, particularly in plants.[15] Dioecy is relatively uncommon in the plant kingdom, and a very low percentage of dioecious plant species have been determined to use the XY system. In most cases where the XY system is found it is believed to have evolved recently and independently.[31]
Since the 1920s, a number of sex determination models have been proposed for Cannabis. Ainsworth describes sex determination in the genus as using "an X/autosome dosage type".[15]
The question of whether heteromorphic
sex chromosomes are indeed present is most conveniently answered if such chromosomes were clearly visible in a
karyotype. Cannabis was one of the first plant species to be karyotyped; however, this was in a period when karyotype preparation was primitive by modern standards. Heteromorphic sex chromosomes were reported to occur in staminate individuals of dioecious "Kentucky" hemp, but were not found in pistillate individuals of the same variety. Dioecious "Kentucky" hemp was assumed to use an XY mechanism. Heterosomes were not observed in analyzed individuals of monoecious "Kentucky" hemp, nor in an unidentified German cultivar. These varieties were assumed to have sex chromosome composition XX.[32] According to other researchers, no modern karyotype of Cannabis had been published as of 1996.[33] Proponents of the XY system state that
Y chromosome is slightly larger than the X, but difficult to differentiate cytologically.[34]
More recently, Sakamoto and various co-authors[35][36] have used
random amplification of polymorphic DNA (RAPD) to isolate several
genetic marker sequences that they name Male-Associated DNA in Cannabis (MADC), and which they interpret as indirect evidence of a male chromosome. Several other research groups have reported identification of male-associated markers using RAPD and
amplified fragment length polymorphism.[37][25][38] Ainsworth commented on these findings, stating,
It is not surprising that male-associated markers are relatively abundant. In dioecious plants where sex chromosomes have not been identified, markers for maleness indicate either the presence of sex chromosomes which have not been distinguished by cytological methods or that the marker is tightly linked to a gene involved in sex determination.[15]
Environmental sex determination is known to occur in a variety of species.[39] Many researchers have suggested that sex in Cannabis is determined or strongly influenced by environmental factors.[27] Ainsworth reviews that treatment with
auxin and
ethylene have feminizing effects, and that treatment with
cytokinins and
gibberellins have masculinizing effects.[15] It has been reported that sex can be reversed in Cannabis using chemical treatment.[40] A
polymerase chain reaction-based method for the detection of female-associated
DNA polymorphisms by
genotyping has been developed.[41]
A male hemp plant
Dense raceme of female flowers typical of drug-type varieties of Cannabis
Cannabis, like many organisms, is
diploid, having a
chromosome complement of 2n=20, although
polyploid individuals have been artificially produced.[43] The first genome sequence of Cannabis, which is estimated to be 820
Mb in size, was published in 2011 by a team of Canadian scientists.[44]
plants cultivated for fiber and seed production, described as low-intoxicant, non-drug, or fiber types.
plants cultivated for drug production, described as high-intoxicant or drug types.
escaped, hybridised, or wild forms of either of the above types.
Cannabis plants produce a unique family of terpeno-phenolic compounds called cannabinoids, some of which produce the "high" which may be experienced from consuming marijuana. There are 483 identifiable chemical constituents known to exist in the cannabis plant,[49] and at least 85 different cannabinoids have been isolated from the plant.[50] The two cannabinoids usually produced in greatest abundance are
cannabidiol (CBD) and/or Δ9-
tetrahydrocannabinol (THC), but only THC is psychoactive.[51] Since the early 1970s, Cannabis plants have been categorized by their chemical
phenotype or "chemotype", based on the overall amount of THC produced, and on the ratio of THC to CBD.[52] Although overall cannabinoid production is influenced by environmental factors, the THC/CBD ratio is genetically determined and remains fixed throughout the life of a plant.[37] Non-drug plants produce relatively low levels of THC and high levels of CBD, while drug plants produce high levels of THC and low levels of CBD. When plants of these two chemotypes cross-pollinate, the plants in the first filial (F1) generation have an intermediate chemotype and produce intermediate amounts of CBD and THC. Female plants of this chemotype may produce enough THC to be utilized for drug production.[52][53]
Whether the drug and non-drug, cultivated and wild types of Cannabis constitute a single, highly variable species, or the genus is polytypic with more than one species, has been a subject of debate for well over two centuries. This is a contentious issue because there is no universally accepted definition of a
species.[54] One widely applied criterion for species recognition is that species are "groups of actually or potentially interbreeding natural populations which are reproductively isolated from other such groups."[55] Populations that are physiologically capable of interbreeding, but morphologically or genetically divergent and isolated by geography or ecology, are sometimes considered to be separate species.[55]Physiological barriers to reproduction are not known to occur within Cannabis, and plants from widely divergent sources are interfertile.[43] However, physical barriers to gene exchange (such as the Himalayan mountain range) might have enabled Cannabis gene pools to diverge before the onset of human intervention, resulting in speciation.[56] It remains controversial whether sufficient morphological and
genetic divergence occurs within the genus as a result of geographical or ecological isolation to justify recognition of more than one species.[57][58][59]
Early classifications
The genus Cannabis was first
classified using the "modern" system of taxonomic
nomenclature by
Carl Linnaeus in 1753, who devised the system still in use for the naming of species.[60] He considered the genus to be monotypic, having just a single species that he named Cannabis sativa L. (L. stands for Linnaeus, and indicates the authority who first named the species). Linnaeus was familiar with European hemp, which was widely cultivated at the time. In 1785, noted evolutionary biologist
Jean-Baptiste de Lamarck published a description of a second species of Cannabis, which he named Cannabis indica Lam.[61] Lamarck based his description of the newly named species on plant specimens collected in India. He described C. indica as having poorer fiber quality than C. sativa, but greater utility as an
inebriant. Additional Cannabis species were proposed in the 19th century, including strains from China and Vietnam (Indo-China) assigned the names Cannabis chinensis Delile, and Cannabis gigantea Delile ex Vilmorin.[62] However, many taxonomists found these putative species difficult to distinguish. In the early 20th century, the single-species concept was still widely accepted, except in the
Soviet Union where Cannabis continued to be the subject of active taxonomic study. The name Cannabis indica was listed in various
Pharmacopoeias, and was widely used to designate Cannabis suitable for the manufacture of medicinal preparations.[63]
In 1924, Russian botanist D.E. Janichevsky concluded that
ruderalCannabis in central Russia is either a variety of C. sativa or a separate species, and proposed C. sativa L. var. ruderalis Janisch, and Cannabis ruderalis Janisch, as alternative names.[48] In 1929, renowned plant explorer
Nikolai Vavilov assigned wild or feral populations of Cannabis in Afghanistan to C. indica Lam. var. kafiristanica Vav., and ruderal populations in Europe to C. sativa L. var. spontanea Vav.[53][62] In 1940, Russian botanists Serebriakova and Sizov proposed a complex classification in which they also recognized C. sativa and C. indica as separate species. Within C. sativa they recognized two subspecies: C. sativa L. subsp. culta Serebr. (consisting of cultivated plants), and C. sativa L. subsp. spontanea (Vav.) Serebr. (consisting of wild or feral plants). Serebriakova and Sizov split the two C. sativa subspecies into 13 varieties, including four distinct groups within subspecies culta. However, they did not divide C. indica into subspecies or varieties.[48][64]
In the 1970s, the taxonomic classification of Cannabis took on added significance in North America. Laws prohibiting Cannabis in the
United States and
Canada specifically named products of C. sativa as prohibited materials. Enterprising attorneys for the defense in a few drug busts argued that the seized Cannabis material may not have been C. sativa, and was therefore not prohibited by law. Attorneys on both sides recruited botanists to provide expert testimony. Among those testifying for the prosecution was Dr. Ernest Small, while
Dr. Richard E. Schultes and others testified for the defense. The botanists engaged in heated debate (outside of court), and both camps impugned the other's integrity.[57][58] The defense attorneys were not often successful in winning their case, because the intent of the law was clear.[65]
In 1976, Canadian botanist Ernest Small[66] and American taxonomist
Arthur Cronquist published a taxonomic revision that recognizes a single species of Cannabis with two subspecies and two varieties in each. The framework is thus:
C. sativa L. subsp. sativa, presumably
selected for traits that enhance fiber or seed production.
C. sativa L. subsp. sativa var. sativa, domesticated variety.
C. sativa L. subsp. sativa var. spontanea Vav., wild or escaped variety.
C. sativa L. subsp. indica (Lam.) Small & Cronq.,[62] primarily selected for drug production.
C. sativa L. subsp. indica var. indica, domesticated variety.
C. sativa subsp. indica var. kafiristanica (Vav.) Small & Cronq, wild or escaped variety.
This classification was based on several factors including interfertility, chromosome uniformity, chemotype, and numerical analysis of
phenotypic characters.[52][62][67]
Professors William Emboden, Loran Anderson, and Harvard botanist
Richard E. Schultes and coworkers also conducted taxonomic studies of Cannabis in the 1970s, and concluded that stable
morphological differences exist that support recognition of at least three species, C. sativa, C. indica, and C. ruderalis.[68][69][70][71] For Schultes, this was a reversal of his previous interpretation that Cannabis is monotypic, with only a single species.[72] According to Schultes' and Anderson's descriptions, C. sativa is tall and laxly branched with relatively narrow leaflets, C. indica is shorter, conical in shape, and has relatively wide leaflets, and C. ruderalis is short, branchless, and grows wild in
Central Asia. This taxonomic interpretation was embraced by Cannabis aficionados who commonly distinguish narrow-leafed "sativa" strains from wide-leafed "indica" strains.[73] McPartland's review finds the Schultes taxonomy inconsistent with prior work (protologs) and partly responsible for the popular usage.[74]
Continuing research
Molecular analytical techniques developed in the late 20th century are being applied to questions of taxonomic classification. This has resulted in many reclassifications based on
evolutionary systematics. Several studies of
random amplified polymorphic DNA (RAPD) and other types of genetic markers have been conducted on drug and fiber strains of Cannabis, primarily for
plant breeding and forensic purposes.[75][76][25][77][78] Dutch Cannabis researcher E.P.M. de Meijer and coworkers described some of their RAPD studies as showing an "extremely high" degree of genetic polymorphism between and within populations, suggesting a high degree of potential variation for selection, even in heavily selected hemp cultivars.[37] They also commented that these analyses confirm the continuity of the Cannabisgene pool throughout the studied accessions, and provide further confirmation that the genus consists of a single species, although theirs was not a systematic study per se.
An investigation of genetic, morphological, and
chemotaxonomic variation among 157 Cannabis accessions of known geographic origin, including fiber, drug, and feral populations showed cannabinoid variation in Cannabisgermplasm. The patterns of cannabinoid variation support recognition of C. sativa and C. indica as separate species, but not C. ruderalis. C. sativa contains fiber and seed landraces, and feral populations, derived from Europe, Central Asia, and
Turkey. Narrow-leaflet and wide-leaflet drug accessions, southern and eastern Asian hemp accessions, and feral Himalayan populations were assigned to C. indica.[53] In 2005, a
genetic analysis of the same set of accessions led to a three-species classification, recognizing C. sativa, C. indica, and (tentatively) C. ruderalis.[56] Another paper in the series on chemotaxonomic variation in the terpenoid content of the
essential oil of Cannabis revealed that several wide-leaflet drug strains in the collection had relatively high levels of certain
sesquiterpene alcohols, including
guaiol and isomers of eudesmol, that set them apart from the other putative taxa.[79]
A 2020 analysis of
single-nucleotide polymorphisms reports five clusters of cannabis, roughly corresponding to hemps (including folk "Ruderalis") folk "Indica" and folk "Sativa".[80]
Despite advanced analytical techniques, much of the cannabis used recreationally is inaccurately classified. One laboratory at the
University of British Columbia found that Jamaican Lamb's Bread, claimed to be 100% sativa, was in fact almost 100% indica (the opposite strain).[81] Legalization of cannabis in Canada (as of 17 October 2018[update]) may help spur private-sector research, especially in terms of diversification of strains. It should also improve classification accuracy for cannabis used recreationally. Legalization coupled with Canadian government (Health Canada) oversight of production and labelling will likely result in more—and more accurate—testing to determine exact strains and content. Furthermore, the rise of craft cannabis growers in Canada should ensure quality, experimentation/research, and diversification of strains among private-sector producers.[82]
Popular usage
Popular terms are discerned from scientific taxonomy by the lack of italics, use of quotes and uppercasing.
The scientific debate regarding taxonomy has had little effect on the terminology in widespread use among cultivators and users of drug-type Cannabis. Cannabis aficionados recognize three distinct types based on such factors as morphology,
native range, aroma, and subjective psychoactive characteristics. "Sativa" is the most widespread variety, which is usually tall, laxly branched, and found in warm lowland regions. "Indica" designates shorter, bushier plants adapted to cooler climates and highland environments. "Ruderalis" is the informal name for the short plants that grow wild in Europe and Central Asia.[74]
Mapping the morphological concepts to scientific names in the Small 1976 framework, "Sativa" generally refers to C. sativa subsp. indica var. indica, "Indica" generally refers to C. sativa subsp. i.kafiristanica (also known as afghanica), and "Ruderalis", being lower in THC, is the one that can fall into C. sativa subsp. sativa. The three names fit in Schultes's framework better, if one overlooks its inconsistencies with prior work.[74] Definitions of the three terms using factors other than morphology produces different, often conflicting results.
Breeders, seed companies, and cultivators of drug type Cannabis often describe the ancestry or gross
phenotypic characteristics of
cultivars by categorizing them as "pure indica", "mostly indica", "indica/sativa", "mostly sativa", or "pure sativa". These categories are highly arbitrary, however: one "AK-47" hybrid strain has received both "Best Sativa" and "Best Indica" awards.[74]
Phylogeny
Cannabis likely split from its closest relative, Humulus (hops), during the mid
Oligocene, around 27.8 million years ago according to
molecular clock estimates. The centre of origin of Cannabis is likely in the northeastern
Tibetan Plateau. The pollen of Humulus and Cannabis are very similar and difficult to distinguish. The oldest pollen thought to be from Cannabis is from
Ningxia, China, on the boundary between the Tibetan Plateau and the
Loess Plateau, dating to the early
Miocene, around 19.6 million years ago. Cannabis was widely distributed over Asia by the Late Pleistocene. The oldest known Cannabis in South Asia dates to around 32,000 years ago.[83]
According to genetic and archaeological evidence, cannabis was first domesticated about 12,000 years ago in
East Asia during the early
Neolithic period.[9] The use of cannabis as a mind-altering drug has been documented by archaeological finds in prehistoric societies in Eurasia and Africa.[86] The oldest written record of cannabis usage is the Greek historian
Herodotus's reference to the central Eurasian
Scythians taking cannabis steam baths.[87] His (
c. 440 BCE)
Histories records, "The Scythians, as I said, take some of this hemp-seed [presumably, flowers], and, creeping under the felt coverings, throw it upon the red-hot stones; immediately it smokes, and gives out such a vapour as no Greek vapour-bath can exceed; the Scyths, delighted, shout for joy."[88] Classical Greeks and Romans also used cannabis.
In China, the psychoactive properties of cannabis are described in the Shennong Bencaojing (3rd century AD).[89] Cannabis smoke was inhaled by
Daoists, who burned it in incense burners.[89]
In the Middle East, use spread throughout the Islamic empire to North Africa. In 1545, cannabis spread to the western hemisphere where Spaniards imported it to Chile for its use as fiber. In North America, cannabis, in the form of hemp, was grown for use in rope, cloth and paper.[90][91][92][93]
Cannabinol (CBN) was the first compound to be isolated from cannabis extract in the late 1800s. Its structure and chemical synthesis were achieved by 1940, followed by some of the first preclinical research studies to determine the effects of individual cannabis-derived compounds in vivo.[94]
Cannabis is a popular recreational drug around the world, only behind alcohol, caffeine, and tobacco. In the U.S. alone, it is believed that over 100 million Americans have tried cannabis, with 25 million Americans having used it within the past year.[when?][97] As a drug it usually comes in the form of dried
infructescences ("buds" or "marijuana"),
resin (
hashish), or various extracts collectively known as
hash oil.[10]
Normal cognition is restored after approximately three hours for larger doses via a
smoking pipe,
bong or
vaporizer.[98] However, if a large amount is taken orally the effects may last much longer. After 24 hours to a few days, minuscule psychoactive effects may be felt, depending on dosage, frequency and tolerance to the drug.
Cannabidiol (CBD), which has no intoxicating effects by itself[51] (although sometimes showing a small stimulant effect, similar to
caffeine),[99] is thought to attenuate (i.e., reduce)[100] the anxiety-inducing effects of high doses of THC, particularly if administered orally prior to THC exposure.[101]
According to
Delphic analysis by British researchers in 2007, cannabis has a lower risk factor for
dependence compared to both nicotine and alcohol.[102] However, everyday use of cannabis may be correlated with psychological
withdrawal symptoms, such as irritability or insomnia,[98] and susceptibility to a
panic attack may increase as levels of THC metabolites rise.[103][104] Cannabis withdrawal symptoms are typically mild and are not life-threatening.[105] Risk of adverse outcomes from cannabis use may be reduced by implementation of evidence-based education and intervention tools communicated to the public with practical regulation measures.[106]
In 2014 there were an estimated 182.5 million cannabis users worldwide (3.8% of the global population aged 15–64).[107] This percentage did not change significantly between 1998 and 2014.[107]
Short-term use increases both minor and major adverse effects.[109] Common side effects include dizziness, feeling tired, vomiting, and hallucinations.[109]Long-term effects of cannabis are not clear.[113] Concerns including memory and cognition problems, risk of addiction,
schizophrenia in young people, and the risk of children taking it by accident.[108]
The term hemp is used to name the durable soft fiber from the Cannabisplant stem (stalk). Cannabis sativa cultivars are used for fibers due to their long stems; Sativa varieties may grow more than six metres tall. However, hemp can refer to any industrial or foodstuff product that is not intended for use as a drug. Many countries regulate limits for psychoactive compound (
THC) concentrations in products labeled as hemp.
Cannabis for industrial uses is valuable in tens of thousands of commercial products, especially as fibre[114] ranging from
paper,
cordage,
construction material and textiles in general, to
clothing. Hemp is stronger and longer-lasting than
cotton. It also is a useful source of foodstuffs (hemp milk, hemp seed, hemp oil) and
biofuels. Hemp has been used by many civilizations, from
China to
Europe (and later
North America) during the last 12,000 years.[114][115] In modern times novel applications and improvements have been explored with modest commercial success.[116][117]
In the US, "industrial hemp" is classified by the federal government as cannabis containing no more than 0.3% THC by dry weight. This classification was established in the
2018 Farm Bill and was refined to include hemp-sourced extracts, cannabinoids, and derivatives in the definition of hemp.[118]
The Cannabis plant has a history of medicinal use dating back thousands of years across many cultures.[119] The
Yanghai Tombs, a vast ancient cemetery (54 000 m2) situated in the
Turfan district of the
Xinjiang Uyghur Autonomous Region in northwest China, have revealed the 2700-year-old grave of a
shaman. He is thought to have belonged to the
Jushi culture recorded in the area centuries later in the Hanshu, Chap 96B.[120] Near the head and foot of the shaman was a large leather basket and wooden bowl filled with 789g of cannabis, superbly preserved by climatic and burial conditions. An international team demonstrated that this material contained THC. The cannabis was presumably employed by this culture as a medicinal or psychoactive agent, or an aid to divination. This is the oldest documentation of cannabis as a pharmacologically active agent.[121] The earliest evidence of cannabis smoking has been found in the 2,500-year-old tombs of Jirzankal Cemetery in the
Pamir Mountains in Western China, where cannabis residue were found in burners with charred pebbles possibly used during funeral rituals.[122][123]
Settlements which date from c. 2200–1700 BCE in the
Bactria and
Margiana contained elaborate ritual structures with rooms containing everything needed for making drinks containing extracts from poppy (opium), hemp (cannabis), and
ephedra (which contains
ephedrine).[124]: 262 Although there is no evidence of ephedra being used by steppe tribes, they engaged in cultic use of hemp. Cultic use ranged from
Romania to the
Yenisei River and had begun by 3rd millennium BC Smoking hemp has been found at
Pazyryk.[124]: 306
Cannabis is first referred to in
HinduVedas between 2000 and 1400 BCE, in the Atharvaveda. By the 10th century CE, it has been suggested that it was referred to by some in India as "food of the gods".[125] Cannabis use eventually became a ritual part of the Hindu festival of
Holi. One of the earliest to use this plant in medical purposes was
Korakkar, one of the 18
Siddhas.[126][127][self-published source?] The plant is called Korakkar Mooli in the
Tamil language, meaning Korakkar's herb.[128][129]
In
Buddhism, cannabis is generally regarded as an intoxicant and may be a hindrance to development of
meditation and
clear awareness. In ancient
Germanic culture, Cannabis was associated with the
Norse love goddess,
Freya.[130][131] An anointing oil mentioned in Exodus is, by some translators, said to contain Cannabis.[132]
Since the 13th century CE, cannabis has been used among
Sufis[140][141] – the mystical interpretation of
Islam that exerts strong influence over local Muslim practices in
Bangladesh,
India,
Indonesia,
Turkey, and
Pakistan. Cannabis preparations are frequently used at Sufi festivals in those countries.[140] Pakistan's
Shrine of Lal Shahbaz Qalandar in
Sindh province is particularly renowned for the widespread use of cannabis at the shrine's celebrations, especially its annual Urs festival and Thursday evening dhamaal sessions – or meditative dancing sessions.[142][143]
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