The method used in Alberta for killing colonies ( In the past when package
bees were bought in the spring and killed in the fall) was to put a
tablespoon of calcium cyanide on a piece of paper, insert the paper into
the lower entrance and close up the hive. The calcium cyanide reacts with
the water vapour in the air to form hydrogen cyanide gas and lime. There
was essentially no contamination of the hive equipment. Cyanide is quite
dangerous, but so is gasoline.



Best regards,

Donald Aitken
Edmonton Alberta Canada