Okay, I accidentally burned some stems when I put some incense in my ash cup and forgot there were stems at the bottom. I came back into my room about thirty minutes later and it reeked of weed, and I was all like "hmm, I don't remember smoking in my room today .. . or in a couple months actually." Anyway, because I was a touch stoned I thought my stash might be on fire, but realized soon that that would be impossible because my stash is in a mason jar in my fridge. Anyway, long story short, I can't do this because my roomies aren't fond of the smell of weed generally and ask me to smoke it outside (which of course, I comply with because they're my close and good friends). However, I recommend that some people try this because if you burn enough stems in an enclosed space, I'm sure that the smoke in the air will make you feel a little funny. The ancient Native Americans of the American West used to hotbox themselves with entire dried cannabis plants burning in a fire under their tipis.