There is a general inverse relationship in the resin of Cannabis between the amounts of THC present and the amount of the other principal cannabinoid, CBD. Whereas most drug strains contain primarily THC and little or no CBD, fiber and oilseed strains primarily contain CBD and very little THC. CBD can be converted to THC by acid catalyzed cyclization, and so could serve as a starting material for manufacturing THC. In theory, therefore, low-THC cultivars do not completely solve the problem of drug abuse potential. In practice, however, the illicit drug trade has access to easier methods of synthesizing THC or its analogues than by first extracting CBD from non-drug hemp strains.
Cannabis can be prepared into various foods generally called ‘edibles’. It takes between 1-3 hours to feel the effects after eating cannabis.2 Impatient or naïve users may believe they have not taken enough to feel the effects, and if they consume more they may find later that the psychoactive effects are unpleasantly strong. When edible products have inconsistent levels of THC even experienced users may find it difficult to regulate the amount consumed.
During my visit, Penny showed me how she administers Harper’s CBD oils. We stood in her kitchen, where a window opened onto a vista of green grass and a wooden swing set out back. After carefully mixing and measuring Harper’s oils, Penny poured the liquid into a jumbo-sized plastic syringe. “We put this all online,” she told me, referring to the several YouTube videos she has made to help other parents administer hemp oil. Penny leaned down over her daughter to fit the tip of the syringe into her gastronomy tube, and I stood by silently. Harper looked at Penny, and Penny smiled back at her, and eased the plunger down.
Fig. 8. Scanning electron micrographs of the abaxial surface of a perigonal bract (which envelops the fruit). These bracts are the most intoxicating part of the plant, and may contain 20% THC, dry weight. The resin is synthesized both in stalked and sessile glands. Multicellular secretory glands (of phallic appearance), some broken stalks of these (note cellular appearance), and unicellular cystolith hairs (claw-like structures) are pictured. Fig. 9. Some important cannabinoids of cannabis resin. D9-THC (delta-9 tetrahydrocannabinol) is the chief intoxicant chemical and predominates in intoxicant strains, while the isomer D8-THC is usually present in no more than trace amounts. CBD (cannabidiol) is the chief non-intoxicant chemical, and predominates in non-intoxicant strains; it has sedative effects. The non-intoxicant CBN (cannabinol) is a frequent degradation or oxidation product. The non-intoxicant cannabichromene (CBC) is typically found in trace amounts in intoxicant strains. The non-intoxicant cannabigerol (CBG) is considered to be a precursor of the other cannbinoids (see Fig. 10).
Air-dried stem yields in Ontario have from 1998 and onward ranged from 2.6-14.0 tonnes of dry, retted stalks per hectare (1-5.5 t/ac) at 12% moisture. Yields in Kent County, have averaged 8.75 t/ha (3.5 t/ac). Northern Ontario crops averaged 6.1 t/ha (2.5 t/ac) in 1998. Statistic for the European Union for 2008 to 2010 say that the average yield of hemp straw has varied between 6.3 and 7.3 ton per ha. Only a part of that is bast fiber. Around one tonne of bast fiber and 2-3 tonnes of core material can be decorticated from 3-4 tonnes of good-quality, dry-retted straw. For an annual yield of this level is it in Ontario recommended to add nitrogen (N):70–110 kg/ha, phosphate (P2O5): up to 80 kg/ha and potash (K2O): 40–90 kg/ha. The average yield of dry hemp stalks in Europe was 6 ton/ha (2.4 ton/ac) in 2001 and 2002.
Cannabis contains a seemingly unique class of chemicals, the cannabinoids, of which more than 60 have been described, but only a few are psychoactive. Cannabinoids are produced in specialized epidermal glands, which differ notably in distribution on different organs of the plant (high concentrations occur on the upper surface of the young leaves and young twigs, on the tepals, stamens, and especially on the perigonal bract). Given this distribution, the glands would seem to be protective of young and reproductive above-ground tissues (the roots lack glands). Two classes of epidermal glands occur—stalked and sessile (Fig. 8), but in either case the glandular cells are covered by a sheath under which resin is accumulated, until the sheath ruptures, releasing resin on the surface. The resin is a sticky mixture of cannabinoids and a variety of terpenes. The characteristic odor of the plant is due to the abundant terpenes, which are not psychoactive. The more important cannabinoids are shown in Fig. 9. In the plant the cannabinoids exist predominantly in the form of carboxylic acids, which decarboxylate with time or when heated. Delta-9-tetrahydrocannabinol (D9-THC, or simply THC) is the predominant psychoactive component. Other THC isomers also occur, particularly D8-THC, which is also psychoactive. Technically, the euphoric psychological effects of THC are best described by the word psychotomimetic. Cannabidiol (CBD) is the chief non-psychotomimetic cannabinoid. A THC concentration in marijuana of approximately 0.9% has been suggested as a practical minimum level to achieve the (illegal) intoxicant effect, but CBD (the predominant cannabinoid of fiber and oilseed varieties) antagonizes (i.e. reduces) the effects of THC (Grotenhermen and Karus 1998). Concentrations of 0.3% to 0.9% are considered to have “only a small drug potential” (Grotenhermen and Karus 1998). Some cannabinoid races have been described, notably containing cannabichromene (particularly in high-THC forms) and cannabigerol monomethyl ether (in some Asian strains). The biosynthetic pathways of the cannabinoids are not yet satisfactorily elucidated, although the scheme shown in Fig. 10 is commonly accepted. At least in some strains, THC is derived from cannabigerol, while in others it may be derived from CBD. CBN and D8-THC are considered to be degradation products or analytical artifacts (Pate 1998a).
Recent European Commission proposals to change its subsidy regime for hemp contained the following negative evaluation of hemp seed: “The use of hemp seed ... would, however, even in the absence of THC, contribute towards making the narcotic use of cannabis acceptable... In this light, subsidy will be denied producers who are growing grain for use in human nutrition and cosmetics.”
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. For Schultes, this was a reversal of his previous interpretation that Cannabis is monotypic, with only a single species. 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.
Going forward, another emerging trend among recreational users are wellness lifestyles built around cannabis. This is certainly part of the influence of California’s new recreational marijuana market, which went online January 1, 2018. California is already an epicenter for health and wellness lifestyles and fads. Expect to see more of the same now that cannabis is completely legal.
Finding cultivars suited to local conditions is a key to success. Hemp prefers warm growing conditions, and the best European fiber strains are photoperiodically adapted to flowering in southern Europe, which provides seasons of at least 4 months for fiber, and 5.5 months for seed production. Asian land races are similarly adapted to long seasons. In Canada, many of the available cultivars flower too late in the season for fiber production, and the same may be predicted for the northern US. Fiber production should also be governed by availability of moisture throughout the season, and the need for high humidity in the late summer and fall for retting, so that large areas of the interior and west of North America are not adapted to growing fiber hemp. The US Corn Belt has traditionally been considered to be best for fiber hemp. There are very few cultivars dedicated to oilseed production (such as ‘Finola’ and ‘Anka’) or that at least are known to produce good oilseed crops (such as ‘Fasamo’ and ‘Uniko-B’). Oilseed production was a specialty of the USSR, and there is some likelihood that northern regions of North America may find short-season, short-stature oilseed cultivars ideal.
C.S. Lewis said “badness is only spoiled goodness.” This may be an apt quote regarding public perception. It’s true that hemp’s scientific name is the same as that other Cannabis sativa, marijuana, but its constituents are different. The three cannabis plants have three different species: Sativa, used for industrial fibers, oils, food, drugs and medicine; Indica, to induce sleep; and Ruderalis, for food production. Hemp seeds contain high amounts of essential fatty acids – more than any fish and most fish oil supplements. The oil has linoleic acid, alpha-linolenic acid, and at least 20 amino acids. Altogether, hemp supplies innumerable health benefits. After decades of misunderstanding, scientists have again been tapping the amazing potential of this versatile plant.
Fig. 2. Cannabis sativa. This superb composite plate by artist Elmer Smith, often reproduced at a very small scale and without explanation in marijuana books, is the best scientific illustration of the hemp plant ever prepared. 1. Flowering branch of male plant. 2. Flowering branch of female plant. 3. Seedling. 4. Leaflet. 5. Cluster of male flowers. 6. Female flower, enclosed by perigonal bract. 7. Mature fruit enclosed in perigonal bract. 8. Seed (achene), showing wide face. 9. Seed, showing narrow face. 10. Stalked secretory gland. 11. Top of sessile secretory gland. 12. Long section of cystolith hair (note calcium carbonate concretion at base). Reproduced with the permission of Harvard University, Cambridge, MA.
But all was not well. Harper has continued to experience health issues related to her condition. And seven months after starting to use CBD oil, Harper’s seizures returned— although not as frequently as before. Penny uses eleven iPhone reminders to keep track of Harper’s daily regimen of medications and food, and she records all of Harper’s seizures in a thickly bound black book. But as her parents continue to closely monitor Harper’s health and adjust her medications accordingly, her doctors are tightly limited in the advice they can offer when it comes to CBD oil. “There’s no research on this product, so they don’t say it’s good or bad. They just say, ‘Don’t stop giving it,’” Penny told me.
The etymology is uncertain but there appears to be no common Proto-Indo-European source for the various forms of the word; the Greek term kánnabis is the oldest attested form, which may have been borrowed from an earlier Scythian or Thracian word. Then it appears to have been borrowed into Latin, and separately into Slavic and from there into Baltic, Finnish, and Germanic languages. Following Grimm's law, the "k" would have changed to "h" with the first Germanic sound shift, after which it may have been adapted into the Old English form, hænep. However, this theory assumes that hemp was not widely spread among different societies until after it was already being used as a psychoactive drug, which Adams and Mallory (1997) believe to be unlikely based on archaeological evidence. Barber (1991) however, argued that the spread of the name "kannabis" was due to its historically more recent drug use, starting from the south, around Iran, whereas non-THC varieties of hemp are older and prehistoric. Another possible source of origin is Assyrian qunnabu, which was the name for a source of oil, fiber, and medicine in the 1st millennium BC.