Two cannabis flower products sit on a dispensary shelf in Grand Forks. Both test at 22% THC. A patient buys the first one and sleeps nine hours. She buys the second one a week later and lies awake reorganizing her kitchen cabinets at midnight. Same THC percentage. Entirely different experience. She returns to the dispensary confused, perhaps a little annoyed, and asks what went wrong.
Nothing went wrong. She was just reading the wrong number.
THC percentage has become the dominant metric by which cannabis consumers choose products. It is, in the language of my former profession, a necessary but insufficient data point. Knowing the THC content tells you something real — how much of the primary psychoactive compound is present. But selecting cannabis by THC percentage alone is like choosing a wine by its alcohol content. A fourteen-percent Barolo and a fourteen-percent Riesling will give you very different evenings, and the reason has nothing to do with the ethanol.
In cannabis, the reason is largely terpenes.
What Terpenes Are
Terpenes are volatile aromatic compounds produced by the trichomes of the cannabis plant — the same structures that produce cannabinoids. They are not unique to cannabis. Myrcene is abundant in mangoes and hops. Limonene is what makes a lemon smell like a lemon. Linalool is the primary aromatic in lavender. You encounter these molecules daily; cannabis just concentrates them in higher and more variable amounts.
More than 200 terpenes have been identified in cannabis, though most products are dominated by a handful. The ones with the most research behind them — and I want to be specific about what "research" means, because the word is used loosely in this industry — are these:
Myrcene
Myrcene is the most abundant terpene in most cannabis cultivars. Preclinical research suggests sedative and muscle-relaxant properties. A 2009 study by do Rego et al. demonstrated anxiolytic and sedative effects of myrcene in mice. It is likely responsible for the "couch-lock" effect that patients associate with indica strains — though as I have written elsewhere, the indica label is less informative than the myrcene content.
Limonene
Limonene has been associated with elevated mood and anxiolytic effects. A 2013 study published in Pharmacology, Biochemistry and Behavior (Lima et al.) found anxiolytic effects of limonene inhalation in animal models. Human evidence remains limited, but the preclinical data is consistent.
Linalool
Linalool, the terpene dominant in lavender, has demonstrated anti-anxiety and sedative properties in multiple preclinical studies. A 2018 study by Harada et al. at Kagoshima University, published in Frontiers in Behavioral Neuroscience, found that linalool odor reduced anxiety in mice through olfactory input rather than bloodstream absorption — a finding with implications for how we think about inhalation methods.
Beta-caryophyllene
Beta-caryophyllene is unusual because it binds directly to the CB2 cannabinoid receptor, making it functionally a dietary cannabinoid. A 2014 study by Bahi et al. in Physiology & Behavior found it reduced anxiety and depression-like behavior in mice. It is also abundant in black pepper, which may explain the folk remedy of chewing peppercorns to counter THC-induced anxiety (though that mechanism is not formally established).
The Honest Limits
Most terpene research in cannabis is preclinical. Animal models and cell studies. The leap from "this compound reduced anxiety in mice" to "this compound will help your anxiety" is real, and it is not small. We do not yet have large, well-controlled human trials on individual cannabis terpenes at the doses present in commercial products.
What we have is biological plausibility, consistent preclinical data, and growing observational evidence from patients who report that different terpene profiles produce reliably different effects — even at identical THC percentages. That is suggestive. It is not proof. I would rather give you an honest "we're getting there" than a confident answer that outpaces the data.
How to Use This Information
If your dispensary provides certificates of analysis — and in North Dakota, they should — look beyond the THC number. Find the terpene section. Note the dominant terpenes and their concentrations, usually reported in milligrams per gram or as a percentage.
If you want sedation, look for products high in myrcene and linalool. If you want something more energizing, look for terpinolene or limonene dominance. If the COA does not include terpene data, that absence tells you something too. (It tells you the information you need to make an informed choice was not considered important enough to provide.)
Then do what any good scientist does with a hypothesis: test it. Try a product, note the terpene profile, record what happened. Try a different profile. Compare. Over time, that personal dataset will be more useful than any percentage on a label.
The woman in Grand Forks who slept nine hours and then reorganized her kitchen — she was not choosing badly. She was choosing blindly. The information she needed was on the certificate of analysis.
Now you do.