Beyond THC: Why You Should NOT Trust Cannabis Lab Results

When it’s time to replenish their stock of marijuana flower, many people walk into a medical or recreational dispensary and head to the bud with the highest percentage of THC. But does the amount of THC listed on the packaging translate exactly to how high a user is likely to get? And does it indicate the quality of the strain in question?



The short answer to both of these questions is no. Let’s dive into the science behind the measurement and meaning of THC percentages and cannabis quality.

Cannabis Lab Testing

Lab testing of cannabis usually falls under two categories: genotyping and chemotyping. Genotyping focuses on the plant’s DNA and genetics, tracing its genealogy back to parent strains. Chemotyping, on the other hand, analyzes the ratios and strengths of the plant’s terpenes and cannabinoids. In other words, chemotyping focuses on the chemical composition of the cannabis sample.

Micro Stile & Stigma of Cannabis

Chemotyping is where analysts uncover the THC percentage found in each sample. Many users believe that the given THC percentage in a strain represents the amount of THC present compared to the overall chemical composition of the product. But in fact, that percentage means something completely different. In the chemotyping analysis of a product, the percent of THC that is ultimately slapped on the label is a representation of THC when measured against the other cannabinoids present.

In other words, out of all of the cannabinoids present within the product (THC, CBD, CBN, and so on), the percent of that total that is measured to be THC is the percentage that goes on the label. This percentage can range from quite low to impressively high, but if the total amount of cannabinoids present in the product is low, even a large percentage of THC won’t necessarily translate to a powerful high.

Trichome Institute

That’s why the Trichome Institute has made it their mission to test cannabis products for actual quality, not simply THC percentages and family trees. They developed what they call the TAG system, which stands for Trichome Assurance Grade. In addition to chemotyping and genotyping, the TAG system tests for potential afflictions or infestations for which the government doesn’t require analysis. Each strain is inspected microscopically to search for fungi (including powdery mildew), jar rot, microscopic pests, spider eggs, and other potentially unhealthy and dangerous characteristics that the flower might possess. During the inspection, the strains are graded based on these results, as well as the overall appearance and aroma of the buds.

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In addition to the visual and aromatic inspection of cannabis, TAG technicians take micro-puffs of the strain being analyzed in order to get a complete understanding of the quality of the flower. Much like a wine sommelier sips, swishes, and spits out a taste of wine without the intention of getting drunk, Trichome-certified Interpeners (cannabis sommeliers trained to interpret terpenes) use these micro-puffs not to get high, but to check for the flower’s burnability and smoothness. These characteristics, as any smoker will tell you, contribute greatly to a strain’s quality.

The TAG System

The TAG system is currently the only cannabis quality certification program available across the globe. Although Interpening courses are available at introductory levels to anyone with an interest, only the most advanced cannabis experts and certified Interpeners are invited to become certified as Level 3 Interpeners and can officially TAG different strains with the most accurate cannabis quality certification reports in both the wholesale and resale industries.

TAG small logo

TAG reports strongly resemble report cards. For each strain, the report includes macro and micro photographs of the flower, its health and appearance, the ripeness of the bud, and even includes everything provided within the previous lab chemotype analysis (levels of cannabinoids, terpenes, pesticides, and microbials). In other words, the report builds a full story of the quality of the cannabis being analyzed.

Of course, it is important to take into consideration the opportunity for human error. After all, who is to say that each Interpener is completely objective? To overcome the possibility of subjectivity, each anonymous strain is graded (out of 100) by two separate Interpeners before a final TAG report is presented. The two grades must fall within 5 numerical points of one another, otherwise, the tests are thrown out and must be started anew. In addition, there is a seven day waiting period after the tests have been completed, during which anyone can challenge the final score. If no challenges are brought up within that week, the average of the two values becomes the official TAG score. This approach adds a level of inter-rater reliability and accuracy to the Trichome Institute and their scoring method.

The TAG is the first and only of its kind, and it is blazing a trail into the industry of cannabis quality assurance. In the future, we can expect to see stores across the country – and across the world – proudly displaying their TAG certifications, and we can certainly hope to see TAG reports accompanying every strain.