It's more than just the maturity of the trichomes, friend. EVERY strain has a different cannabinoid profile, which means different concentrations of the various (at least 40) cannabinoids. delta9-thc (that's me, and you're welcome ) is the active ingredient which gets you high. delta1, delta6, and delta8-thc seem to affect things like time-to-onset as well as duration (time to metabolize). cannabidol (CBD) and cannabinol (CBN) are more body high/down manipulators, while tetrahydrocannabinol (THC) and tetrahydrocannabivarin (THCV) are more mind high/down manipulators. There are somewhere around 40 cannabinoids, last I checked, and we don't know what all of them do, as yet. It is thought that these other cannabinoids merely interact with the major ones (THC, THCV, CBD, CBN) to change the experience further, thus diferentiating from the various strains even more. What that link above shows you is how maturity affects trichomes and makes more or less CBD, which is how not only is every STRAIN containing a unique cannabinoid profile, but every BATCH of a strain could be different.
the thing is though, all of them except delta9thc are in really minute quanitities, so not much is known about exactly how psychoactive each is. however, just as many psychedelics require tiny doses to work, it is probably the same case with these 'lesser' cannabinoids. However there is no way you will ever know how much of each chemical is in your weed, unless your an active scientist doing dangerous (because of legal implications if your found with drugs, and lab equiptment!) or working for the govt. but yeh, the dominant one is always delta-9 thc, the others just give diferent sort of 'lean' of the effects, like the main differences between indica and sativa if your really interested in teh subject, look into the way cannabinoids effect your brain. (there was a scientific american on it a few months ago, if you need some direction)
Heres a link to the Scientific American article: http://scientificamerican.com/article.cfm?chanID=sa011&articleID=0008F53F-80F7-119B-80F783414B7F0000