The term trichome comes from the Greek and is derived from the word “Tríchōma,” which means “growth of hair.” Strictly speaking, trichomes are the so-called glandular hairs (not to be confused with the flower hairs) and are formed, among other things, by the cannabis plant, but also, e.g., by sundew (however, in a different chemical composition than in cannabis). Trichomes are typically unicellular, forming glandular secretory units on the calyxes and pistils of mature, unfertilized female cannabis flowers. They are microscopic superstructures; they contain the essence of the psychoactive properties of the cannabis plant.
Trichomes are often thought of as small biological factories for producing the unique cannabinoids found primarily in the flowers of cannabis. However, one not only finds cannabinoids in the trichomes; you can also find various terpenes and flavonoids in them. The potency of the cannabis plant, taste, and smell are inextricably linked to the process that takes place in the cells of the trichomes.
Very roughly, one can say that the THC-rich trichomes are responsible for the psychoactive effect and the CBD-rich trichomes are responsible for the therapeutic effects of the marijuana plant.
The calyxes (grow from the calyx of the female marijuana plant) are visible to the naked eye as hair-like threads and, as mentioned earlier, are often mistaken for trichomes. A highly complex biosynthesis takes place there. In the process, metabolites are created (including the unique cannabinoids found in marijuana), over a hundred different terpenes are produced, and finally secreted as resins; these then accumulate in secretory cavities. It is the plant’s survival strategy in nature. Terpenes are involved in resistance to pathogens and herbivores. They are “unsaturated hydrocarbons” and flavor enhancers responsible for the different flavors and smells of cannabis strains.
The ingredients THC, i.e., tetrahydrocannabinol and other cannabinoids (such as cannabidiol, CBD for short), are produced exclusively in the heads of the trichomes. It works because the plant has so-called organelles, on the one hand, the vacuoles (these contain phenols), and on the other hand, plastids, which contain terpenes. These migrate from the stem to the head and mix in the secretory cavity to form a fibrous coating. If UV-B light waves hit this resulting coating, it changes into cannabinoids. It means that all psychoactive ingredients are produced exclusively in the trichomes. So one needs these hairs for concentrate and hash making.
The amount of trichomes does not necessarily say anything about the potency of the plant. Instead, it is due to the potency of the resin, which in turn depends on the composition of individual cannabinoids. A comprehensive potency measurement is almost impossible since different amounts of cannabinoids produce other effects. However, it is possible to determine the content of the individual cannabinoids, but this does not necessarily say anything about the cannabis strength.
How many trichomes there are on a plant and what type of trichomes it ultimately depends heavily on genetics and environmental conditions. Even on a plant, the trichomes themselves can vary greatly. You can find three primary forms of trichome in the literature:
- Tuberous trichomes
- Trichomes with a head, without a stem
- Trichomes with a head and stem
Tuber trichomes are one of the most miniature types, measuring only 15 to 30 microns. They form a small “foot,” a stem, and a head with just a few cells.
Trichomes with a head, without a stem
The second type, called capitate sessile, ranges in size from 25 to 100 microns and is more common than the tuber trichome. This species is comparatively low in cannabinoids.
Trichomes with a head and stem
The third type of trichome (capitate-stalked) is the most significant, ranging in height from 150 to 500 microns, and is visible to the naked eye. Above all, this is formed during flowering and can be found in high concentrations on the bracts of the flowers; these are important for seed protection.
All three trichome types produce cannabinoids; by far, the richest and most effective way to do this, not least because of their size, is with the third type of trichome.
Although contrary to some belief, male cannabis plants produce trichomes, the amount is negligible. Additionally, these trichomes have a different cannabinoid profile than female cannabis strains.
What is the role of trichomes in the cannabis plant? Scientists believe that trichomes perform essential, if not vital, functions. The sticky resin coating on the surface forms a protective layer against mold, insects, and herbivores. In addition, trichomes even form an organic sunscreen and protect the marijuana plant from the sun’s UV rays.
Many insects and certain types of mold find it impossible to break through the trichome barrier, while terpenes spoil the taste of many herbivores.
Usage & extraction
Since the nature of resin, and therefore trichomes, is mainly responsible for the characteristics of cannabis, there is a direct correlation between trichomes and the quality of the extracts produced.
The extraction methods are far-reaching, from sifting and pressing the plant material to hash oil. Trichomes are always the starting material, so it is the starting material for manufactured concentrates and hash.