Cedar oil literally melts them. After weeks of trying everything we could get our hands on ($$$ gone), I tried straight up cedar oil in a spray bottle and found immediate delight in watching those motherfuckers writhe in agony as they shriveled and died. The others tried helplessly to flee, but I was undaunted and hunted them down, one by one. None lived to tell the tale, and all were chemically dessicated and vacuumed up.