Resin Gland Density

Resin gland density refers to the concentration and distribution of trichomes—the crystalline structures that produce cannabinoids, terpenes, and other secondary metabolites—across a plant's aerial surfaces. This trait is typically assessed visually during flowering, with higher densities appearing as frosted or crystalline coatings on flowers and leaves. Resin gland density is a heritable characteristic influenced by both genetics and environmental factors like light intensity, temperature, and humidity. Breeders commonly select for dense resin production as an indicator of potency and terpene concentration, though visual density alone does not determine cannabinoid ratios. This trait is documented across diverse lineages and is particularly emphasized in modern breeding programs targeting concentrate production.

Breeders working in this category often use resin gland density as a primary visual selection criterion during phenotype hunting and cross development. High resin-producing lines are frequently retained for creating hybrid vigor and establishing stable traits in seed lines or clonal libraries.