It lacks some desirable properties as chemical warfare agent. For one, it doesn't disperse easily and is even noticable at low concentrations. Meaning if you fi

It lacks some desirable properties as chemical warfare agent. For one, it doesn't disperse easily and is even noticable at low concentrations. Meaning if you fill at trench with this, it is likely your own trench will notice it too and you won't be able to enter the field for a bit. And everything in the field will stink too for a while, so you can't take advantage of some resources there.