>Allen, my suggestion of "weather" as a variable was completely arbitrary--I
>was simply trying to make the point that without a control group, one can't
>really state that the increased drops were due to the experimental
>treatment.
I realise what you were saying, but in a sense, that proof is provided by the
repeated applications and the subsequent mite drops. Granted, this is not
absolute proof, but there does seem to be a cause and effect. That effect,
though, does diminish and is not as pronounced after the change of evaporation
devices from Cowan to Heilyser. That lowered response bears investigating
further, but appears to be due to the lack of remaining mites.
I would feel quite safe in concluding, from comparing the drops in the various
hives and the various times, that the drops are associated with something
that is happening when I use the applicators and evaporate oxalic acid
inside the hives. I had already ruled out temperature and other possible
factors, but have now added a mean temperature plot to the chart so you
and others can see what I had already seen -- and eliminated.
>And without a control group, one can't say whether your four treatments
>with oxalic vapor were of any benefit in mite control over natural
>mortality at that time of year.
Inasmuch as greatly enhanced drops occurred in almost all hives in the days
immediately following these events, it seems highly probable there is a causal
relationship. There are, however several anomalies which have been
discussed in the diary. The lack of response to one treatment in one hive at
one time could be attributed to negligence on the part of the applicators, a
fluke in the machine, or intervention by the omnipresent Murphy.
The one anomalously high drop (64) in a hive which dropped almost zero every
nearby day before and after is a mystery and is likely due to Divine Intervention
on behalf of the long-suffering bees or the oft-demonstrated incompetence of
the principal investigator. It could also be explained by the phrase, "These things
happen". They do and most self respecting experimenter would cook them out
of the records, but I don't have to look good, and besides, I think it could be
significant.
Whatever it is -- assuming I did not make a big goof, and I did not -- if we could
identify it and cause it to happen at will, we would not need oxalic or any other
such treatment. Dee spoke of 'clean out events' as I recall. Was this a one-day
cleaning bee? (Sorry, couldn't resist).
>My point: if one is trying to determine the efficacy of any sort of
>treatment or management technique, one MUST include controls!
Sometimes the controls are internal, like this. Granted, having some untreated hives
would make things more kosher, especially if I never interfered with them in any
way, like changing drop boards every day.
***********************************************
The BEE-L mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software. For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html
Guidelines for posting to BEE-L can be found at:
http://honeybeeworld.com/bee-l/guidelines.htm
|
