A friend recently acquired some DMT, and chose to make enhanced leaf from it using only mullein. Mixed it with a bit of 99% IPA and mullein, and let it sit infront of a fan overnight. It was dry the next afternoon, so he bagged it up to store. Last night he decided to smoke some, but when he lit it up the material sort of caught on fire rather than burning the way weed does. Is this supposed to happen? He's worried that there may be traces of IPA in his leaf.... Please tell me this isn't the case.

If it's completely dry and doesn't smell of IPA you should be good.

Sometimes mullein can catch the flame pretty easy, so use just enough heat to get an ember going and hit it long and slow after that.

I always let it dry, then mix it all up and spread it around and leave to dry again. If you do this 3 or 4 times it should all be gone.