Whether considering the recreational or medical benefits of cannabis, therapeutic value is derived from cannabinoids and terpenes, the “miracle molecules” that deliver relief for everything from depression and gastrointestinal problems to cancerous tumors and epilepsy.
But from where are these compounds derived?
Both cannabinoids and terpenes are manufactured in small resin glands present on the flowers and main fan leaves of late-stage cannabis plants called trichomes. Derived from the Greek word trikhōma, which means “growth of hair,” trichomes are nearly microscopic, mushroom-like protrusions from the surface of the buds, fan leaves, and — in lower numbers — even on the stalk. While relatively complex, trichomes are comprised primarily of a stalk and a head. It is within the head that the actual production of cannabinoids like THC occurs.
There are actually three types of trichomes: Bulbous, capitate-sessile, and capitate-stalked. Bulbous are the smallest and barely visible to the naked eye, whereas capitate-stalked, the largest variety, is what most people notice when viewing cannabis flowers, either with the naked eye or under magnification. While more research is necessary to reveal how these types differentiate from one another, it is believed that all trichomes manufacture all types of cannabinoids and terpenes.
Chemicals called vacuoles and plastids (which contain terpenes) are manufactured in the stalks of the trichomes and travel up to the head of the gland. Once in the head, ultraviolet (UV) light combines with them to help create cannabinoids. While a highly simplistic definition, this model illustrates why plants that have received light of the proper wavelength, intensity, and duration produce a greater volume of cannabinoids. When that cannabinoid happens to be THC, the euphoric potency of the plant obviously increases.
However, it should be noted that a blanket of sugary trichomes on a particular cannabis sample doesn’t ensure potency in the form of strong medical efficacy or mind-bending euphoria. While a bounty of resin glands is certainly a good sign, it doesn’t necessarily mean that those glands contain a high percentage of THC, CBD, or other effective cannabinoids and terpenes.
From a biological perspective, it is believed that trichomes evolved as the cannabis plant’s defense mechanism, protecting it from threats in its environment, including insects and animals. Trichomes make consumption of the plant less palatable to hungry predators. They are also known to inhibit some types of fungal growth and believed to protect the plant from high wind and low humidity.
Red Flag for Gardeners
Trichomes also indicate the state of maturity of female cannabis plants in the final stages of growth. When clear, plants are not yet fully mature. If harvested when the trichome stalks appear cloudy or milky in color, the cannabinoid profile will typically deliver a more heady, energetic, and sativa-like high. If allowed to grow even longer, trichomes will achieve an amber or brown color, meaning the cannabinoids will deliver a more relaxed body high that’s stereotypically associated with indica strains.
It should be noted that various strains of cannabis indicate their readiness for harvest, via the color of their trichomes, in different ways. There are actually a few strains that do not become amber when it’s time for harvest. Gardeners should be familiar with the characteristics of a particular strain before relying too heavily upon the appearance of trichomes to determine their harvest schedule.
The Source of Kief, Hash, & Shatter
Because trichomes are the microscopic factories in which cannabinoids and terpenes are produced, they are the core material of many types of cannabis extracts and concentrates. Kief, the powdery cousin of hash, is basically a collection of decapitated trichome heads. Hash is a similar extraction of trichomes intended to gather cannabinoids and terpenes. Because hash is pressed, the trichomes often become crushed and the resin material co-mingles and begins to cure (at least on the outer regions).
Bubblehash is when cannabis leaves and sometimes flowers are soaked in ice water until the trichomes become frozen and brittle. When a small bit of physical agitation is applied, the trichomes detach and fall from the plant matter and are gathered by a fine screen at the bottom of the water reservoir. Shatter, BHO (butane hash oil), wax, and glass are simply different methods of collecting and processing the resin of the plant to produce a more potent medicine that involves less smoking and significantly higher percentages of coveted cannabinoids like THC and CBD.
Despite celebration of the plant’s green leaves and buds, it is actually the nearly invisible sugary crystalline trichomes that provide all medical or recreational value. Patients must remember that it isn’t the lovely green plant matter in their bowl or joint that is providing them with relief, but rather the sprinkling of resin glands in which are suspended compounds like THC and CBD.
This post was originally published on August 17, 2015, it was updated on November 6, 2017.