A long time ago, when only landrace genetics existed in the genus Cannabis, the terms Cannabis sativa L. and Cannabis indica Lam. were created to identify these two species of the Cannabaceae family. Today, those taxonomical terms have been shortened to sativa and indica, but they can still be confusing—and sometimes quite misleading—for the casual toker, the new medical marijuana patient and even the everyday stoner.
The differences between these two species are far-ranging: everything from how the plant looks, to how it grows, to how its effects are experienced when consumed. But why do these differences exist? Why does an indica plant grow shorter than a sativa? Why does a sativa deliver such a distinct psychoactive experience as compared to an indica? To arrive at these answers, we must use genealogy and scientific data to trace today’s strains back to their original landrace. Having loads of lab results, such as cannabinoid levels and terpene profiles, also helps this endeavor quite a bit. So we invited a knowledgeable friend from High Times’ partner lab, Steep Hill Halent, to weigh in … and what we found may surprise you.
Origins of Indica and Sativa
While there is no way to determine how long cannabis has been growing on the planet, the earliest evidence of human use dates back thousands of years to the Far East. The origins of the indigenous cannabis landraces have been traced to South and Central Asia, with wild cannabis stretching from the fringes of the Middle East all the way to China and Mongolia further north. But how did different species of cannabis develop separately around the same latitudes of Earth?
Like all living organisms, the cannabis plant has evolved and adapted to its environment (and continues to do so to this day). With the native regions of cannabis located in relatively close proximity to one another, the answer to why the species evolved differently lies in examining their climates of origin. These climates can vary greatly due to the difference in geographic locales, ranging from the foothills of the Himalayas, to the lowlands of the Hindu Kush valleys, to the peaks of the Rif Mountains in Morocco.
The Rif Mountains of Morocco, home to a variety of landrace strains.
According to Kymron deCesare, chief research director at Steep Hill Halent Lab in Oakland, CA, the major difference in evolution between sativas and indicas is that sativas developed to take advantage of a humid environment. This includes the development of thin, lanky stems and long, narrow leaves to promote greater respiration. Indicas, on the other hand, developed to survive in drier, more arid climates, evolving into short, stocky plants with thick, stubby leaves designed to minimize the loss of water through respiration. It thus stands to reason that thousands of years ago, true landrace indicas such as the short, squat Afghanica could be found at higher elevations, where the air was thin and brisk and the water scarce. Meanwhile, in the valleys below were the sativas, growing lean and tall in the lush, wet forest areas.
Fast-forward a couple thousand years to 1753, when a young scientist named Carl Linnaeus first classified the Cannabis genus using what would become the modern taxonomic nomenclature. At the time, Linnaeus thought the Cannabis genus was monotypic—meaning having only a single species—and he named that species Cannabis sativa L. (the “L.” stands for “Linnaeus,” to indicate the authority who first named it). Three decades later, in 1785, another noted scientist and evolutionary biologist, Jean-Baptiste Lamarck, identified a second species of cannabis that he named Cannabis indica Lam. (for “Lamarck”) after examining the plant specimens he had collected in India. Finally, in the early part of the twentieth century, a group of Russian botanists and plant explorers identified a third species known as ruderalis. C. ruderalis is unlike C. sativa and C. indica in that it is a hardier, fibrous plant much like hemp and possesses little to no THC, making it non-psychoactive.
Hindu Kush, a pure indica landrace from the mountains of northern Afghanistan.
Examples of Pure Landrace Strains
Cultivation and Physical Aspects
These evolutionary trends aided the earliest cannabis plants in terms of respiration, thereby increasing their rate of photosynthesis, which in turn increased flower and seed production—thus ensuring that their genetic lines would survive and thrive.
Today, in much the same way, marijuana growers utilize the evolutionary characteristics of indicas and sativas to boost their yields, depending on the grow environment provided in their gardens. Indoor growers may desire shorter plants due to space constraints and therefore choose indica varieties to grow. Outdoor growers may have to contend with a hot and humid climate much of the time and therefore choose the better-respiring sativas. Or an outdoor grower may find that the hardier, stockier indicas are more resistant to pests in the garden, while an indoor grower may find that thin, wispy sativas are more resistant to molds or powdery mildew in their growroom.
Everything depends on the environmental conditions of the grow space and the individual characteristics of the strains chosen by the grower. And even then, the result isn’t as predictable as it may sound, since every genotype has the possibility of exhibiting new traits (or phenotypes) that can vary immensely from the norm when the plants are grown in conditions to which they’re unaccustomed. In other words, what you see with indicas and sativas isn’t always what you get.
This Blue Dream is a sativa-dominant hybrid with a suspicious indica effect.
Indica- and Sativa-Dominant Hybrids
The term “hybrid” is potentially a confusing one, since anything that isn’t a 100 percent pure landrace—a rare commodity these days—is technically a hybrid strain. For High Times’ purposes at our Cannabis Cups, as well as for this list, we use a 70/30 ratio to determine whether a cannabis species is dominant in any given strain. Anything lower than 70/30—for example, a 60/40 or 50/50 ratio—is considered a non-dominant or well-balanced hybrid.
Examples of Sativa-Dominant Hybrids
Examples of Indica-Dominant Hybrids
Girl Scout Cookies
Cannabinoids, Terpenes and Psychoactive Effects
But what about the different effects that you get from smoking indicas versus sativas? And how intrinsic are those effects if the environmental conditions can vary so much from garden to garden? Well, that’s where things get really interesting.
Many cannabis users experience the sativa “high” as uplifting and cerebral, while the indica “stone” is more of a body buzz that may couchlock the user for hours in front of the TV. But can these effects be directly attributed to the differences between these two species—and, if so, why?
“The terms sativa and indica are only really valid for describing the physical characteristics of the cannabis strain in a given environment,” deCesare said. “They are not nearly as reliable as terms for making assumptions about energy versus couchlock.”
That’s because by its very nature, THC’s effects are energetic—meaning that both sativas and indicas possess a level of THC that will create an uplifting, euphoric feeling when smoked. So why do some indicas leave you in a vegetative state instead?
According to deCesare, sativas and indicas generally share the same cannabinoids as well as the same terpenes—the chemical compounds found in cannabis that contribute to the flavor and aroma of the flowers. These terpenes, or terpenoids, are also found in many other plants; indeed, they create the essential oils and extracts that we use for fragrances and perfumes. Not only do terpenes exist in sativas and indicas, but they exist in similar ratios as well.
However, deCesare points to one major exception that helps explain the differences in psychoactive effect between sativas and indicas: namely, “the consistently elevated levels of the terpenoid myrcene in C. indica, as compared to C. sativa.” In fact, according to the numerous studies he’s conducted along with cannabis researchers like Dr. Donald Land and Dr. Ethan Russo, “myrcene is the major ingredient responsible for ‘flipping’ the normal energetic effect of THC into a couchlock effect.”
This means that what many of us thought about indicas versus sativas isn’t necessarily true: The THC that is typically associated with the psychoactive properties of cannabis is not the only factor at work in making us high. In fact, the theory of the “entourage effect” proposed by Dr. Russo, which holds that different combinations of cannabinoids and terpenes work together to create the distinctive effects from one strain to another, is a much better explanation for the psychoactive differences between sativas and indicas. Indeed, as far as deCesare is concerned, the terpenoid myrcene is the single most important variable in determining these effects.
Asked about the evidence used to support this conclusion, deCesare replied: “This can only be reliably determined through the lab testing of cannabis. When we started doing analytics on cannabis, there were maybe 1,000 different strains. That number now exceeds approximately 3,000 strains. This conclusion is based on the analysis of over 100,000 different samples tested over the last seven years.”
The high trichome count on this Russian Kabul is not what is responsible for its couchlock effects.
Glorious … Myrcene?
As far as terpenes go, myrcene is pretty common—it exists in many other fruits and plants grown the world over. Mangoes and hops are perhaps two of the best-known when it comes to elevated levels of myrcene.
“Notice the warm, relaxed feeling you get from a couple of hoppy beers?” deCesare asked. “That effect is, to a good extent, due to the myrcene present from the hops.”
So what myrcene levels are necessary to get you feeling really relaxed—or stoned, as most of us would say? The research done at Steep Hill Halent suggests that a myrcene level at or below 0.4% in flowers doesn’t have much impact on the “energetic effects” that THC contributes. But when the myrcene content starts to head past 0.5%, “the strain becomes increasingly more sedative and stony,” deCesare noted. “OG Kush is considered by most to be a strong couchlock flower at about 1.25% myrcene. A few strains have a myrcene content in excess of 3%. Other chemicals may well play minor roles in the couchlock effect, including CBD, CBN and linalool, when they are present in couchlock strains—but they aren’t always present or as influential.”
In conclusion, I asked the good Dr. deCesare what possibilities and opportunities the future might hold for legal cannabis.
“Moving forward to a time when the USDA [US Department of Agriculture] and FDA [Food and Drug Administration] oversee cannabis-distribution regulations,” he replied, “they will insist on accurate labeling to assure that if a customer purchases an energetic strain—or a couchlock strain—then what they get is what they paid for. And the only reliable way to make this determination is by lab-testing for myrcene content.”
Interestingly, a recent study released by the National Institutes of Health and published by the National Library of Medicine, Discriminating the Effects of Cannabis sativa and Cannabis indica, noted that in a survey of medical cannabis users, “a preference for C. indica was [shown to be] statistically significant for pain management, helping with sedation and sleep. C. sativa was preferred for euphoria and enhancing energy. The conditions reaching statistical significance for C. indica preference were: non-migraine headaches, glaucoma, neuropathy, spasticity, seizures, insomnia, and joint pain. For C. sativa, no conditions reached significance.”
Burmese Kush (L), an indica-dominant hybrid, makes you feel stoned. Brainstorm Haze (R), a sativa-dominant hybrid, makes you feel high.
Unfortunately, due to the legal ramifications for the private labs and universities that can actually do this type of work—to say nothing of the lack of federal funding available for cannabis-related research—this particular study was conducted via an anonymous Internet survey, which means that it lacked the basic conditions of a proper clinical trial. The researchers who conducted the survey admitted as much, concluding in their abstract that the study “had limitations, with the two species having different effect associations on symptoms and conditions, possibly because of ingredient differences. Future surveys and subsequent prospective definitive trials are needed to confirm the findings” (emphasis added).
“Possibly because of ingredient differences”—such as, say, varying combinations of cannabinoids and terpenes? As for the need for “future surveys” and “subsequent … definitive trials,” well, guess what, NIH and our friends in the federal government: We’re already way ahead of you. Isn’t it time that you caught up?