I've seen a lot of colonies with Apistan hive strips installed,  spring
   or fall, and the queen continuing to lay, apparently normally.
 
   That's not to say fluvalinate strips cannot harm queens, though.
   At the Canadian Apicultural Research Symposium last week  in Edmonton,
   Dr Rob Currie of Manitoba reported a set of trials with Apistan queen
   tabs in queen cages.
 
   The details will be coming in a proceedings, but as I remember, adverse
   effects on queens  were slight at three days of exposure, definite at
   seven days of exposure (the treatment min-max range). Effects were
   increase mortality (40 % at 7 days, compared to 10%) and possibly
   increased supercedure (but not statistically significant).
 
   Placement of the tab under the screen, rather than completely in the
   cage, resulted in slightly less effect.
 
   Only 1 of 151 varroa subjected to this treatment, survived.
 
 
   Kerry Clark, Apiculture Specialist
   B.C. Ministry of Agriculture
   1201 103 Ave
   Dawson Creek B.C.
        V1G 4J2  CANADA          Tel (604) 784-2225     fax (604) 784-2299
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