DJ Short
Spectrum of Effects
The first spectrum to consider is the "up and down". "Up" refers to the stimulating aspects of cannabis, while "down" refers to sedative qualities. Up pot tends to liven the disposition and stimulate the emotions, inspiring sociability and talkativeness. Down pot tends to produce sedative and depressant effects. Some people refer to stimulating pot as being a "head" high and sedative pot as being a "body" high, yet although partially true this is also misleading.
Body and head highs are the next spectrum of the cannabis experience. Generally speaking, head highs are stimulating and body highs are sedative, but not all are. Some body highs are stimulating and some head highs are depressing. I once sampled a terribly paranoia-inducing head pot that inspired great couch lock qualities. I called it Boo-Goo.
Early to late harvest will affect the head to body spectrum expressed by a certain plant, with the later harvest tending to produce more body and sedative effects. However, I believe that certain aspects of this spectrum to be genetically inherited.
Next to consider are aspects of duration. Some cannabis tends to be short-acting (15-30min) whereas other varieties last much longer (6-7 hours). Once again production, harvesting and curing techniques can influence aspects of this spectrum, but much of this effect is inherited.
For me, the most important aspect of the cannabis experience to consider is tolerance. This refers to the product's ability to provide the same experience via the same amount over time – the burnout factor. By "over time" I mean the long run: months, years, decades...
Most of the cannabis I see on the market today has a terrible tolerance factor – a quick burnout time with the product's novelty lasting less than a week. Luther Burbank's model of breeding needs to be employed here and no expression of tolerance to your product is to be tolerated. An example of where intolerance to tolerance is tolerated – enough already!
Another aspect of tolerance is "ceiling." This refers to how high (or far) one is capable of going with the variety. How many hits can you consume until more hits are unnoticeable? Most indicas have a low ceiling of less than 10 hits. For me that's usually around 5 hits in one smoking session. If I smoke more than 5 hits of a strong indica I will either not notice the post-ceiling hits, or I will fall asleep.
Some sativas have a very high ceiling, or seem to have none at all! This means that the more you consume, the higher and further you go. Oaxaca Highland Gold, Black Magic African, and Highland Thai were some of the herbs I've tried with very high or no ceiling.
The final aspect of mental effects to consider when sampling strains for breeding is the tendency to produce anxiety. Certain strains of cannabis increase anxiety while others decrease it. This is also true for other emotions, which some strains may suppress while others may augment their intensity. Generally stimulating and head varieties are the ones that can produce unwanted anxiety, but this is not always the case. Quickly cured buds or an over-early harvest are contributing factors to anxiety-increasing pot, but this trait is also genetic in nature.
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