Recent Observations on Environmental Effects

Although there is a vast older literature on the effects of various environmental manipulations on marijuana, it is of no use for present purposes since the observations usually didn t pertain to cannabinoid content. Even when they did, there were no good tests for quantitative measurement of the active compounds. 

The studies on wild hemp in Illinois and Indiana attempted to correlate many factors of soil content with cannabinoid production, but nothing conclusive emerged. Both studies agreed 

The cannabinoid concentrations were always greater for all four types under cool conditions of growth, but total yield of cannabinoids was probably greater in the warm conditions. Nepalese and Jamaican plants had three to four times greater THC concentrations in the cool temperatures, while Illinois plants had six times more and Panamanian plants were about equal. The first three populations doubled their CBD in the 

maximum total yield of THC will probably not be obtained under the conditions which give the strongest product. 

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