Reasonable thinking, but perhaps not the most appropriate time periods:
the "varroa protected in the brood cell" period is not the same as the
full developmental time for a drone. The period from when a varroa mite
enters a cell shortly before capping, until the host bee emerges, is
maybe 13 days for workers, 16 days for drones.
So a 45 day treatment covers more than 3 cycles for workers, and well
over 2 cycles for drones.
I expect that several other factors (fluvalinate diffusing to wax, etc)
were considered when the treatment period recommendation was being
decided.
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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