Trichomes (from the Greek trikhōma, meaning "hair"), are fine outgrowths or appendages on plants, algae and certain protists. They are of diverse structure and function. Trichomes help prevent seed damage from insects, animals, light degradation and fungal disease.
In the case of cannabis, trichomes also contain tetrahydrocannabinol (THC). Near the end of the flowering cycle, THC begins to break down and turns into another chemical compound called cannabinol (CBN) in a process known as oxidization. Higher levels of CBN tend to provide a more narcotic or “stoned” feeling, while THC delivers a more euphoric, upbeat “high”. Growers examine the trichomes and the pistils of the plant, key signatures in deciding when to harvest.
The classical cannabinoids are concentrated in a viscous resin produced in structures known as glandular trichomes. At least 85 different cannabinoids have been isolated from the Cannabis plant. The best studied cannabinoids include THC, cannabidiol (CBD) and CBN.