I found this jar in my smoke room that had been sitting here since last year. It still smells the same as I remembered but it’s very brown now.
Did it get brown bc it’s not been in the dark?
I pressed some and the rosin is darker too.
It got me wondering why. What am I pressing out that is now more brown than before? Is it trichome heads that have reacted to the sun. It never had direct sunlight on it either.
It’s been oxidized over time. That’s why it’s brown and the rosin is darker. Thc converts to cbn over time going from clear/cloudy to amber.
I have always assumed that the three enemies of cured buds are heat, light and pressure. I have screwed up on all three categories numerous times.
Degraded/decarbed cannabinoids no longer in the -acid form, and decaying/aged plant matter. Will make effects less potent and less stimulating, more sedating/boring, usually, but potentially more useful for some medical issues. Aged plant matter (waxes, lignin/cellulose/etc, chlorophyll) isn’t going to be any more harmful than fresh stuff afaik
Anything I want to keep long term goes in a jar in the freezer, otherwise the previously dank, tasty strain is weak and musty. If you got it to retain its smell for over a year, good for you!
As the chlorophyll breaks down over time, the color changes from green to brown.
I have weed that wasn’t impressive become quite the sleep weed after siting a year
6-18 months is the magic number for me in jars in a dark closet. Older is ok too but that’s my sweet spot.
But yes oxidation for sure. I’d argue that a little is actually a good thing.
Came across some very old outdoor bud in an old ice cream tub last month, White Widow 2007. Dry as a bone, made some into cookies and the rest went to bubble hash.
I think it’s mostly the chlorophyll degrading like in all plants as they turn brown. Of course thc degrades but I think the brown is not the exact same as any potency lost.
i found a baggie of weed under the seat of a truck that had been parked for about seven years and lost probably a few before that about four years ago. i’m scared to try it though.
I found some in a drawer of a desk for sale at Goodwill once. Just felt a need to pull out that drawer and bam, there it was. Old little bud of something. Don’t remember if I tried to smoke it 
I bought an ashtray for my prelude a couple decades ago from a junkyard and it came with 4 or 5 joint touches 
