Terpenes are organic compounds produced by a variety of plants, particularly conifers, and some insects. Terpenes create the scents and flavors of cannabis and some believe they may also influence its effects. For example, Linalool supposedly helps induce relaxation and aid in pain management, while Pinene is believed to increase alertness and aid in memory retention.
Terpenes are produced by trichomes, the small “hairy” projectiles that form on the flowers of cannabis. Trichomes make both terpenes and cannabinoids such as THCA and CBDA, which turn into THC and CBD after decarboxylation. Needless to say, trichome development is an important aspect of cannabis cultivation.
The aromas and flavors of cannabis are mostly due to its terpene “profile.” Each strain or cultivar will have its own taste and aroma, and the notes found within this signature are often used to identify, label, and even sell different strains or cultivars—for example, diesel, woody, herbal, pine, citrus, skunk, spicy, tropical, etc.
A reliance on scent to determine the quality—and effects—of a particular cultivar has long been in use. Cannabis that has been professionally cultivated and “cured” exhibits a pungent, yet pleasant aroma. Of course, preferences for aroma and flavor are subjective, and different aromas will appeal to different tastes.
Besides the strain itself, growing and harvesting techniques may also affect the terpene profile. Light, soil, and nutrients can all have an impact, as can the timing of harvest, since harvesting too soon may not enable trichomes to develop robust terpene or cannabinoid profiles.
Terpenes and Terpenoids
Terpenes are hydrocarbons made of hydrogen and carbon, but when cannabis is dried (“cured”) its terpene molecules are oxidized, converting terpenes to terpenoids. Technically speaking, cannabis that is ready for consumption has mostly terpenoids, since it has had time to oxidize the terpenes present.
Terpenes and the Entourage Effect
The idea behind the “entourage effect” is that a mix of compounds in combination with one another will have a more potent and synergistic effect than the individual compounds might have alone. It is believed that terpenes and cannabinoids can actually either accentuate or minimize the effects of one another, depending on the compounds present in the cultivar and how one responds to them.
Types of Terpenes
Although well over a hundred (and counting) terpenes have been identified in cannabis, only a limited number are consistently present in significant amounts.
Myrcene is one of the most prevalent terpenes found in cannabis. Most cultivars contain at least some of this terpene. It has an “earthy” aroma and has been observed to be an effective anti-inflammatory. Myrcene is found in thyme, mango, hops, and lemongrass, and is known to increase the effects of THC. It is also said to relieve muscle tension, promote sleep, balance mood, reduce swelling, and have anti-inflammatory and soothing effects.
Cultivars rich in Myrcene are White Widow, Himalayan Gold, Blue Dream, Remedy, Skunk XL, 9 Pound Hammer, Grape Ape, Special Kush, Grandaddy Purp, OG Kush, Pink Kush, Tangie, and Cherry Pie.
Caryophyllene is found in hops, cinnamon, black pepper, cloves, basil, oregano, and rosemary, and has an herbal aroma reminiscent of such plants. Caryophyllene is the only terpene that can act as a cannabinoid since it also interacts with the body’s ECS (Endocannabinoid System). It is said to promote sleep, combat free radicals, reduce swelling, and act as an anti-inflammatory.
Cultivars rich in Caryophyllene are Skywalker, Sour Diesel, Chem Dawg, Bubba Kush, OG Kush, Super Silver Haze, Rock Star, Original Glue, and Purple Punch.
Pinene is found in pine needles, orange peels, rosemary, basil, and parsley, and is responsible for the “piney” aroma of some cultivars. Like Caryophyllene, Pinene has anti-inflammatory properties and may act as a bronchodilator. Some believe it may also reduce memory loss and aid in the treatment of asthma, arthritis, Crohn’s disease, and even cancer. It is believed to lessen or counterbalance the effects of THC.
Cultivars rich in Pinene are Jack Herer, Strawberry Cough, Blue Dream, Dutch Treat, Snoop’s Dream, Island Sweet Skunk, Critical Mass, OG Kush, and Romulan.
The name Limonene denotes its aroma, which is like lime or lemon. All citrus fruits contain Limonene, as does Juniper and Peppermint. Limonene is believed to improve mood, reduce stress, relieve anxiety, and combat free radicals. Cultivars with “lemon” or “sour” in the name are usually rich in Limonene.
Cultivars rich in Limonene are Durban Poison, White Fire O.G., Wedding Cake, O.G. Kush, Super Lemon Haze, Sour Diesel, Jack Herer, Do-Si-Dos, and Jack the Ripper.
Terpinolene (aka Terpineol)
Terpinolene has a floral aroma with citrus notes and is found in plants known for their fragrances, such as rosemary, lilacs, apples, and some conifers. It is mainly considered a relaxer, yet some believe it to also have an uplifting effect. It is said to reduce swelling and combat dependency.
Cultivars rich in Terpinolene are Trainwreck, Super Lemon Haze, Pineapple Kush, Royal Jack Automatic, Ghost Train Haze, Chernobyl, Girl Scout Cookies, Jack Herer, and OG Kush.
Humulene has an earthy or “hoppy” aroma and is present in wood, hops, cloves, basil, sage, black pepper, and ginseng. Humulene is known to reduce inflammation, relieve pain, and have anti-bacterial properties. It is also said to reduce swelling, aid in discomfort, and suppress appetite.
Cultivars rich in Humulene are Skywalker OG, Sherbert, White Widow, GSC, Headband, Sour Diesel, Pink Kush, and Girl Scout Cookies.
Linalool has a floral aroma and is found in lavender, birch bark, mint, rosewood, bergamot, cinnamon, coriander, and rose. Linalool encourages relaxation and is also believed to help with pain management, depression, arthritis, seizures, insomnia, and even cancer. It is also said to reduce swelling and promote calmness.
Cultivars rich in Linalool are Kosher Kush, Amnesia Haze, Do-Si-Dos, Special Kush, Lavender Kush, LA Confidential, and OG Shark.
Bisabolol (aka Levomenol)
Bisabolol has a floral aroma and is found in chamomile and candeia. It is known to reduce skin inflammation and have anti-bacterial, antioxidant, and analgesic properties. Some have suggested that it has promise as an anti-cancer agent as well.
Cultivars rich in Bisabolol are Harle-Tsu, Pink Kush, Oracle, OG Shark, Pink Kush, Headband, Master Kush, and AC/DC.
Nerolidol has a woodsy aroma with floral notes and is found in jasmine, lemongrass, and tea tree oil. It is believed to have antifungal, antimicrobial, and anti-inflammatory properties, and can supposedly also act as an anti-parasitic and anti-cancer agent.
Cultivars rich in Nerolidol are Island Sweet Skunk, Jack Herer, Sour Diesel, Girl Scout Cookies, Blue Dream, Chem Dawg, Dieseline, and Skywalker OG.
Camphene has an earthy aroma reminiscent of pine or fir needles. Strains that have a lot of Camphene are sometimes mistaken for those dominant in Myrcene (or Pinene) since they have similar scents. Camphene is believed to be an antioxidant and antifungal agent, and may help with pain management.
Cultivars rich in Camphene are Strawberry Banana, AC/DC, Banana Kush, OG Kush, Mendocino Purps, and Ghost OG.
Borneol has a woodsy aroma with citrus notes and is found in rosemary, camphor, and mint. It is a natural insect repellent with anti-inflammatory, anticoagulant, and supposedly pain-relieving properties.
Cultivars rich in Borneol are Amnesia Haze, Golden Haze, and K13 Haze.
Eucalyptol (aka Cineole)
Eucalyptol is found in eucalyptus trees and has a distinctive, refreshing aroma. It is an antibacterial and antifungal agent believed to also help with detoxing, swelling, and pain management.
Cultivars rich in Eucalyptol are Harle-Tsu, Pink Kush, OG Shark, AC/DC, Super Silver Haze, and Headband.
Ocimene has an herbal aroma with citrus and woodsy notes and is found in mint, parsley, orchids, mangoes, and basil. This terpene acts as an anti-inflammatory, antiviral, and antifungal, and may offer uplifting, euphoric, effects.
Cultivars rich in Ocimene are Dutch Treat, Amnesia, Golden Goat, Strawberry Cough, Chernobyl, Space Queen, Dream Queen, Golden Pineapple, Green Crack, Clementine, Lemon Sour Diesel, Elwyn, OG Kush, Frankenstein OG, and Jimi Hendrix Purple Haze.
Guaiol (aka Champacol)
Guaiol has a “piney” aroma with fruity undertones and is found in guaiacum, cypress, lemons, and tobacco. This terpene has antibacterial and antioxidant properties, and is believed to combat free radicals and even inhibit the growth of lung cancer cells.
Cultivars rich in Guaiol are Great White Shark, Headband, Island Sweet Skunk, OG Shark, Master Kush, Sour Diesel, Afghani, Royal Gorilla, Chocolope, Kali Dog, Blue Kush, Amnesia Haze, Liberty Haze, Cherry Hill, Sour Tangie, White Widow, Jean Guy, and Barbara Bud.
A New Taxonomy
Landrace strains are strains indigenous to a particular area. For example, “Thai” is Sativa from Thailand, “Panama Red” is Sativa from Panama, “Hindu Kush” is an Indica from the Kush Mountain Range on the Afghanistan-Pakistan border, “Durban Poison” is a Sativa from the Durban area of South Africa, and “Acapulco Gold” is a Sativa from Mexico.
Cultivars, on the other hand, are strains cultivated for particular traits unrelated to a particular geographic area and its traditions of planting and harvest. They are not necessarily tethered to a geographical area, nor to a genetic seed base that has been recycled from prior crops indigenous to a that area. Rather, they are independent of region in that they are individually cultivated with a particular trait or traits in mind.
As cannabis classification becomes more fine-tuned, terms such as “Sativa” and “Indica” could become less relevant since they are used to describe a plant’s physical traits and geographic origins. As terpene and cannabinoid profiles become a more standard means of identifying strains and their effects, other means of identification may become less relevant.
Cannabis and Terpene Additives
The terpene profile of a particular cultivar may be altered after production via terpene additives. This process is sometimes referred to as “re-infusion.” These terpene additives can be organically or synthetically derived. “Synthetically derived” simply meaning that the terpenes are created in a lab, not isolated from natural origins. Either way, the molecular structure of the added terpene(s) should be the same.
This process has opened up a market for “concentrates,” which could be terpene- or cannabinoid-rich “juice” sold as “extracts,” “sauce,” or “distillate.” All are types of cannabis concentrates—however, this doesn’t mean the terpenes in them were derived from cannabis, since they can be extracted from other organic sources or even created synthetically. These are the same terpenes, just derived from different sources.
Terpene Effects on Cannabis Users
With some terpenes, the effects of THC are strengthened—say, with Myrcene—while others, such as Pinene, may weaken or “counterbalance” THC’s effects. This may explain why a low THC-content strain might feel more intense than strains containing more. Myrcene may also amplify the effects of THC due to its ability to facilitate compounds in crossing the blood-brain barrier.
A Final Important Word on Terpenes
One word of warning about terpenes is that some concentrates, if heated to high temperatures (e.g., vaporizing), can produce toxic byproducts. For example, some terpene mixtures have been observed to form methacrolein and benzene at high temperatures, both of which are known carcinogens. Obviously, more research needs to be done regarding this downside, since it is a dangerous one.
Undoubtedly, the future will see more emphasis on the creation of precision strains via terpene, THC, and cannabinoid manipulation. Indeed, the possibilities for organic, synthetic, and combination blends seem endless.