What are you trying to get at?
A plant who's cellulose turns to alcohol at 180 degrees is a lot bigger fire hazard than your run of the mill vegetation. Particularly if it's big, fibrous plants.
You are prepared to defend the cost of the inevitable property damage and loss of life in order to accomplish your goal of causing some second or third degree burns to the handful of marijuana smokers who are too dumb to set a match to a pinch of it before they harvest or buy it, aren't you?
BTW, back in the Carbonoferous Age the air had quite a bit more oxygen than it does now. When lightning would hit a large plant it would burst into flames.
And when it comes to fire hazard, hot cellulose is no more risky nor does it contain any more calories than alcohol.
It's just that alcohol is much more convenient to deal with than a double-retort reduction system.