> If I can get formic gel in time I may try and dose this hive.

At the SBA meeting I recall seeing a presentation showing that long duration
formic treatments do suppress brood rearing when applied in the spring, whereas
the short duration treatments do not.  At the same meeting, Medhat described the
long term formic method he has adapted to Ontario conditions, but did not AFAIK
address this issue.  I'm hoping he might comment on this aspect of formic
treatment now, and whether he has observed it.

> Next to this hive is a control hive. It is getting Apistan treatments
> twice a year. This hive has strips in it now due to high mite count in the
> drone brood

Preparing and maintaining control hives for comparing varroa treatments is a
problem.

If the controls are adjacent the treatment hives, drifting of significant
numbers of bees between them is likely.  The exact levels of drifting depend on
a number of factors, including breed of bee.  10% is not unusual.  Moreover,
apparently bees tend to drift from heavily infested hives to less infested ones.

If the hives are separated by a distance, that does not exclude them from the
problem of bees abandoning crashing hives, and also introduces the difference in
location --  rather than the treatment -- as a possible explanation for any
differences noted.

Moreover, all hives should be as similar as possible at the beginning of the
test.

When we consider this and the fact that one hive has a history of infestation
and a recent treatment going in to the test and the other does not, it would
seem that meaningful conclusions will be hard to reach in this case.

I don't know how the researchers deal with this problem.

allen
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