Hoser wrote:I heard of a neat way to kill roaches.......baking soda. Just spread some of it in the areas they seem to populate, and as they scurry across the stuff they will ingest enough of it that when it gets to their digestive system it will start to bubble and expand. Seeing as how they have no way to get rid of the gas build up they just basically get killed from the internal build up of pressure. They don't blow up or anything like that (that would be really cool if it did happen though) they just die within a few minutes.
I think that explanation was conjured up by someone who had a really nasty vendetta against the critters The explanation I've heard, and which seems far more plausible, is that the exoskeletal breathing mechanism is interfered with -- basically, the roach gets coated in soda and then suffocates.
I imagine you could get the exact same results with flour, except that would attract all kinds of unwelcome pests, and any flour you missed cleaning up under the baseboards and such would eventually hatch out a new generation of grain weevils.