Cannabis flowers that were not pollinated during cultivation and do not contain seeds. May also refer to the cultivation technique to create seedless cannabis. The term sinsemilla originates from the combination of two Spanish words: “sin” (without) and “semilla” (seed). Cannabis flowers that mature without pollination have higher levels of essential oils and are notable for being more psychoactive than seeded cannabis. Sinsemilla may also be spelled and pronounced “sensimilla” or “sensimilia,” or abbreviated as “sensi.”
A brief history of sinsemilla cannabis
Before and during the 1970s, cannabis in the United States came in primarily two forms: as hashish and cannabis buds. Dried cannabis flowers imported to the United States from Mexico, Jamaica, Colombia, Panama, and Thailand, among other places, were wild-grown and minimally processed. Primarily known as marijuana by authorities and regulatory bodies, and referred to as grass, pot, and reefer, among many nicknames for the plant by everyone else, this cannabis had copious amounts of seeds. As domestic cannabis production in the United States began to take off in the 1970s, it was discovered that culling male plants before maturation so as to avoid any pollination would result in seedless buds after harvest.
It is not known who first coined the term sinsemilla, but it is theorized that both the cultivation method and the name originated in the southwestern United States. Due to the inherently higher THC content of seedless cannabis than seeded, this product was popularized as a new and potent type of cannabis. The misconception spread that sinsemilla and marijuana were completely different varieties of cannabis, and not the reality that they refer to the same plant simply grown with different cultivation techniques. This dichotomy between the two was used in anti-cannabis propaganda to spread the notion that cannabis was getting stronger, and therefore would allegedly begin to represent an even greater mental health concern to youths, thus needing to be eradicated.
As cannabis consumers realized the advantages that seedless cannabis had to offer (ease of smoking, increased potency, etc.), cultivators increasingly produced more and more sinsemilla. Breeding techniques were developed that allowed growers to grow seedless cannabis for distribution, while selectively pollinating particular branches of the healthiest females) in the crop with pollen from a separate crop of selected male breeding stock. Seeds secured from a few pollinated branches, if carefully germinated to assure a high success rate, can sow a crop for the following year. Advances in greenhouse technology led to the popularization of indoor cannabis cultivation, which further facilitated the production of seedless cannabis, as male and female cannabis plants could be grown adjacently, but in airtight containment to prevent unwanted pollination. The advent of feminized seeds facilitated hobbyist growing by allowing a grower to directly plant a crop of all-female plants sown from purchased, “feminized” seeds, without the need for complex breeding programs.
As seedless cannabis became the norm, the term sinsemilla fell into disuse.
The biology of sinsemilla: why is it more potent?
The development of the sinsemilla growing technique sparked an increase in potency of market cannabis for two reasons. Not only does seedless cannabis contain more THC, but its advent and spread also were the first time selective breeding was used to choose specimens for their increased potency.
The exact biological mechanism describing the increased potency of seedless cannabis from seeded has not been properly studied in a rigorous, scientific manner. However, an understanding of the descriptive botany of cannabis has provided a sound explanation for this phenomenon.
Female cannabis plants begin to flower when the days get shorter in the late summer. The amount of time it takes from the first sign of showing flowers to when they are fully ripe and ready to harvest in the fall is commonly referred to as its flowering period. Wild-grown, fertilized cannabis plants produce seeds during this time, and eventually drop them and die as temperatures cool in the fall. However, unfertilized cannabis lives longer and continues to produce flowers for up to a month longer than if it were fertilized. Vegetative growth of the stem and leaves would have ceased at the beginning of the flowering cycle, so all further growth happens in the buds, which become larger and more developed.
In addition to the extra lifetime of unfertilized female cannabis, the extra available metabolic energy that would have otherwise been dedicated to seed production is also thought to be a factor for the increase in potency. Cannabinoids are a component of the sticky oleoresin that forms on the outside of the bracts, the part of the anatomy which holds the seeds. It has been postulated that a lack of hormone-directed metabolism for the production of lipids and proteins in the seed will cause an amplification of the other, existing metabolic pathways: cannabinoid, terpene, and flavonoid biosynthesis.
The increased cannabinoid production in sinsemilla is very clear when looking at available data that tracks cannabis potency from the last 20-30 years. According to an Archival Report from the Society of Biological Psychiatry, the main factor driving the increase in potency of cannabis in the United States is the increase in the proportion of high potency seedless relative to seeded cannabis.
Edible, nutrient-dense cannabis seeds are sought by small, foraging animals.
In the wild, cannabis has adopted the survival strategy of producing the maximum amount of seeds it can before death in the hopes that enough remain to sow the next generation the following spring. The seeds can make up to 50% of the mass of a dried, seeded cannabis bud, which represents a significant hardship for distribution and consumption of seeded cannabis.
For consumers, seeds are a nuisance that require users to meticulously pick through the buds by hand. Smoked seeds create an unpleasant flavor reminiscent of a coal-fired stove.
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