Quote Originally Posted by MullManiac
Still there after 7km. And the highest mountains on earth are 7 km high so you couldnt physicly grow them any higher.
Wait, you are overexagerating what I'm trying to prove. I'm not saying one should grow there plant at such an altitude. I am only saying that one could yield a better quality resin (THC) at an higher altitude because this would expose cannabis to more UV-B. It wouldn't be very wise to take your plant soooooo high of an altitude (7km!? Not that high, bro!) because of lack of carbon dioxide (CO2)

Something else i should point out, you are only taking in one factor, that is very variable! differant places on earth at different times have different UV levels! one thing consistant with altitude is CO2 and O2 levels, which would have a great affect on the plant, also the temp would play a hugh roll not to mentions the high winds.
Dude, I stated that in the second link, two posts ago. You must have didn't read it: http://zebu.uoregon.edu/text/UV
Come to think of it you couldnt grow plants at high alltitudeds at all without the help of man made devices.
Again, the plants should not be grown at an altitude of 7km, it is too high of an altitude. I'm saying that an higher altitude plant grown (but not too high as to not provide that plant carbon dioxide, 7km c'mon) would yield better quality resin (THC) than a low landed plant, because the plant grown at an higher altitude would be exposed to more UV-B.
And do you have any statistics that show the UVb light decreases dramaticly enough over 7km?
Yeah, read some of the links carefully that I previously posted (you will find the info in there somewhere, I don't feel like quoting it) and ask any grower with experience and reliable knowledge whether cannabis grown at an higher altitude compared to a low altitude plant produced better quality resin (THC) or vice-versa.