>I offered this question -- to which I know the answer and on which I have already consulted several practicing experts -- to the "Informed Discussion of Beekeeping Issues and Bee Biology" to see if -- with all the talk of IPM -- anyone really knows how to do it.


In order to do IPM correctly, one has to have an economic threshold in mind. To my knowledge, no one has established an economic threshold for varroa mites that would apply to all regions. And I doubt that anyone would ever recommend doing the sampling in the winter. One could sample in early spring and still obtain sufficient data to make a decision on whether to treat or not.

I would sample every apiary. Low levels may mean the entire apiary can be left untreated; high levels would indicate a need to treat the whole apiary.  I don't see how a sample of 5 bees would ever yield meaningful data. I have always used 250 and often the number of mites is in the 5 to 10 range (per 250 bees), which might never even show up in a sample of 5 bees.  Was that part of the question a joke? Any attempt to denigrate the principles of IPM is misguided in my opinion. Thresholds need to be determined, either officially or by individual beekeepers.

Sampling is not a difficult job to do, and 250 bees per hive will not be missed. If the mite counts are very low, 5 or less, one could conceivably skip a spring or fall treatment, or employ a non-pesticide approach like drone removal, to keep the population from increasing. If the count is high, like 25 or more ( 1 bee in 10 has a mite) -- treatment should not be skipped. IPM never includes sacrificing the livestock when a safe, effective treatment is available.

There is no one right way to do IPM. The approach implies using least toxic controls first and only resorting to heavy chemicals when faced with *potential* economic losses. This is a decision that has to be made case by case. There is an "incorrect" way to control pests and that is to spray first and ask questions later.