An Introduction to Cannabis Trichomes Leave a comment
Anatomy of glandular trichomes
If you’ve ever seen a flower, odds are that you’ve also seen trichomes – more accurately called glandular trichomes – without even noticing them. Glandular trichomes are present in approximately 70% of all flowering plant species all around the world and perform a variety of key functions to aid in a plants ability to communicate, as well as survive. The compounds act as insecticides, pollinator attractors, aromatics, and communication chemicals so that plants can communicate with each other as well as their environment.
The reason you might miss trichomes in the wild is that they are typically very small in size. So small in fact that they are measured in µm (micrometers), but on cannabis plants, glandular trichomes can be seen by the naked eye. The reason for this is generations of selective breeding strains of cannabis, over countless generations, to select genetic traits in the cannabis plants for larger glandular trichome structures.
Why selection for larger glandular trichomes is favored among cannabis growers, is a result of a happy accident of biochemistry that enabled humans and cannabis plants to form a symbiotic relationship. The cannabinoids the plants produce are able to modulate our own endocannabinoid systems via a type of “lock and key” interaction where certain cannabinoids in the cannabis plant match closely enough to our own endocannabinoids as to be able to fit and modulate the CB1 and CB2 receptors in our bodies.
There are multiple types of cell structures that make up a glandular trichome. These cell include: epidermal cells which make up the stem’s exterior (skin), hypodermal cells which make up the stem’s interior, basal cells which make up part of the excretion tip, stripe cells which are the mid-point cells of the excretion tip, secretory cells which are the cells that excrete all of the fluid.
Glandular trichomes on a plant are similar to hormon and sweat glands in animals in several ways. They both produce scents, chemical compounds, lipid molecules and various other excretions vital in the most basic of biological processes. Where plants and animals differ however is the chemicals those glands produce.
As far as cannabis and other flowering plants are concerned, they produce: terpenes, terpenoids, phytochemicals and cannabinoids – which is why breeders of cannabis plants have selectively bred larger and larger structures for so many successive generations.
The governing of cannabis properties and effects
In cannabis plants, there are three different types of glandular trichome structures: bulbous, capitate sessile, and capitate-stalked. The cellular structures – as mentioned above – of these three types do not change, the types are simply names that are given to different shapes and yields of glandular trichomes. Cannabis plants, particularly marijuana females, have larger trichomes than male hemp plants as well as having them in greater numbers. This is the factor that makes THC more abundant in marijuana plants than in hemp plants. Contrary to popular belief however, hemp plants do indeed contain THC in minute concentrations of approximately <0.035%. Any higher and the plant can no longer legally be called hemp.
As a glandular trichome forms and ages it begins to fill with clear fluid that over time becomes cloudy as the concentrations of terpenes, terpenoids, cannabinoids and phytochemicals start to increase. The exact ratios of these compounds is what is used as the primary means of identifying a cannabis strain.
If a plant reaches advanced maturity before it is harvested by a grower, the fluids on the tips of the glandular trichomes turn to an amber color, burst, and release all the contents of the tip of the glandular trichome. This signals the environment announcing the plant’s defence mechanisms, reproductive potential, edibility and pollination potential. But overall, it is a marijuana plant’s last ditch effort to reproduce before the end of the season.
Over generations, cannabis growers have learned to influence ratios of the compounds found in cannabis plants by altering growing conditions and inducing or reducing the stresses on a plant. For example, UV light increases terpene production and increases the expression of terpene producing genes. Although this does not alter the overall parameters of the strain being cultivated, it can increase or decrease the potency of the flower in the end product, depending on how much UV light the grower exposes the plant to.
Through the selected breeding methods outlined above and the alterations of growing conditions such as: UV exposure times, temperature, soil composition and watering frequency, growers have managed to produce approximately 1024 genetic possibilities for cannabis plants each with their own unique balance of medicinal properties.
Summary
Who would have guessed that such small structures could determine such a strong symbiosis between cannabis and humans. Through countless generations of selective growing combined with the already fascinating properties of hemp and marijuana, growers across time have managed to give us a plant that holds medicinal value so vast we have yet to figure out how to make full use of it.
There are ongoing studies that are looking into how different cannabinoid and terpenoid profiles can be tailored as targeted medicines for the specific needs of individuals with wide ranges of conditions.
Many years of research lie ahead, but rest assure that glandular trichomes will remain as the stars of the majority of the discoveries still to come. Remember to stop by our shop and order some flowers! Once you do, get your hands on a magnifying glass and take a look at glandular trichomes up close. Would you be able to identify them by one of the 3 types?
References
Cannabinoids, Terpenes & Trichomes Webinar , Presented by Carlos Jose Angel Hermida, M.B.A,, Hosted by Florida Cannabis Coalition, 2017
What are trichomes? | Cannabis Glossary , Leafy, 2021
Controlling Terpenes and Cannabinoids in Flower and Extract Presented At Cannabis Sciences Virtual Event 2018, Presented By Markus Roggen, PhD VP Extraction, OutCo
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