Dr Frank Eischen at USDA Weslaco has been assessing the relative
   toxicity of smoke from various materials, to varroa and bees, to see if
   some such method might contribute to varroa management.
 
   I think there have been 2 brief reports in ABJ, one in Frank's column
   and another in the ABRC proceedings (2 or 3 years ago).
 
   As I recall, one of the smoker materials found to be most toxic to bees
   (but not mites) was corrugated cardboard, although with usual smoker use
   a toxic effect wouldn't likely be noticeable.  Corrugated cardboard is
   very variable and is often made from recycled used cardboard. Perhaps
   only occasional pieces have a toxic component, but I don't find it a
   very nice smoke anyway.
 
   Personal preference: dry poplar twigs. They're available within steps of
   nearly every yard near here (I have to keep a pail of them in the truck
   for days after a rain) and have a pleasant campfire smell. (I'll also
   use nice dry cow or horse manure if it's handy).
 
   Kerry Clark, Apiculture Specialist
   B.C. Ministry of Agriculture and Food
   1201 103 Ave
   Dawson Creek B.C.
        V1G 4J2  CANADA          Tel (250) 784-2231     fax (250) 784-2299
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