The capitate-stalked trichome is the dominant resin gland on mature female cannabis flowers. It has a multicellular stalk, often 150-500 µm long, topped by a globular head about 60-100 µm across. In the head, a disc of secretory cells pumps resin into a storage cavity under a waxy cuticle. Livingston et al. (2020) showed these stalked glands develop from sessile-like precursors as flowers mature, and produce more monoterpenes and cannabinoids than sessile glands.
In practice
These are the glands you inspect for harvest timing. Heads go from clear to cloudy as resin fills and changes, then some turn amber as they age and oxidise. Cloudy heads are often described as peak-full; amber means ageing.
They are also the ones lost to rough handling. Trimming, bagging and warm, dry handling shear heads off their stalks. That is a big part of why buds should be handled cold and gently, and why trim method is a trade-off.
Gland density varies widely by genotype and plant age (Punja et al. 2023).
Don't confuse with
A dominant allele is one whose effect shows in the phenotype even when only one copy is present, masking the other (recessive) allele at that locus.A monoterpene is a ten-carbon terpene made from geranyl pyrophosphate, such as myrcene, limonene, pinene or terpinolene; they are the most volatile terpenes and the first lost in drying.A cannabinoid is any compound that binds the body's cannabinoid receptors or shares the typical cannabis terpenophenolic structure; the plant-made ones are phytocannabinoids such as THCA and CBDA.The span of days, often one to two weeks, in which a cannabis plant is ripe enough to cut, judged mainly by trichome head colour and bud development.The genotype is the set of alleles a plant actually carries, either at one locus or across its whole genome, as opposed to the traits you can see.A glandular trichome with a resin head but little or no stalk, sitting close to the surface of leaves and young bracts.The smallest glandular trichome on cannabis, a few cells with a tiny head (about 10-30 µm), scattered over leaves and stems.A non-glandular, claw-shaped hair on cannabis leaves that contains a calcium carbonate crystal (cystolith); it makes no resin.A hair-like outgrowth of the plant's skin; in cannabis the glandular types make and store the resin holding cannabinoids and terpenes.In cannabis, the small leaf-like sheath (perigonal bract) that wraps each female flower's ovary and carries the densest capitate-stalked trichomes.The maturity of glandular trichome heads, read by colour under magnification: clear (immature), cloudy or milky (mature), then amber (ageing).
