Don't do it, it's basically
pointless and (obviously) a fire/burn/smoke hazard.
It can be useful for orchards b/c only a few degrees can be crucial to avoid a frost killing all the blossoms. A few degrees is not going to make any difference to chickens.
Also your chickens will be *in the coop* on the coldest nights, yes? so they will not benefit from it anyhow.
Plus which, chickens are really pretty cold tolerant, certainly for Missouri temperatures; also, there are a whole big lotta other, much more effective, much safer, things you can do if you are concerned about their coldness.
A lot of these Big New Ideas that people get, ones that do not hinge on some new piece of just-invented technology, you have to remember there is more often than not a REASON why experienced folks do not in general do that...
Good luck, have fun,
Pat