gassing after the warren is empty, would defeat the object of gassing, think your thinking of the contraption that ignites gas, totally different to gassing rabbits, the one that collapses the burrows in not the thing to use, in my opinion
your right mate.the farmer on my permission uses it well he aint used in a cpl year.used to the burrows in heavy cover.if i remeber correctly it had stupid name like terminator or something like that.he explained it to one day and by law the burrows had to be clear.cost him a few grand apparently