> I have been monitoring natural mite fall this summer during
> approx. 2 months : I counted max. 5 mites/hive/week
> (I was not using sticky boards)                ^^^^
>
> When I treated my colonies at the end of August with Apistan,
> the mite drop increased to a few hundered mites the first two
> days and then decreased very fast.

> This corresponds with what I found on a danish website :
> natural mite drop x 100 = real varroa population in the colony.

This latter result seems to me to be very much in line with what we found in
early September.

At that time we got one mite in 40 hives in 24 hours by natural mite fall, but
then found about 51 as I recall using a 24 hour 2 strip Apistan test on the same
40 hives (see my earlier post for details).  However we were using sticky
boards.  I'm curious how you counted the drop without them.  Were you using a
screen bottom and paper?

At the time we tested, there was anywhere from a frame to three frames of brood
in the colonies, so I am assuming that there were many more mites in cells than
on bees.  If the Danish site used a one week natural fall, their benchmark
(700 -- *assuming* that the one mite we got with natural drop in 24 hours can be
multiplied by 7 to get a 7 day drop) would be very close to what I estimate.

Personally, I have a lot of trouble understanding the idea of leaving more than
*a handful* of mites in a colony going into wintering because of the fact that
if there are a few hundred -- or thousands -- of mites going into winter, we
know that they are going to go into the first several hundred -- or thousand --
cells sealed when the bees raise brood in January and reduce the vitality and
life expectancy of that limited amount of brood and the very important first
bees, n'est-ce pas?

Maybe a few hundred bees is not many, and this is acceptable once you get used
to the idea, but I have problems with it.  A few hundred cells is only a few
square inches and the bees raise a hundred or more square inches once they start
up, but anything that damages the bees makes them even more vulnerable to the
factors that already cause us hive losses in early spring.  Maybe I'm missing
something?

Anyhow, I don't know how many have visited the varroa resources on my "Varroa
and Formic" page which is accessible from the menu on the left side of
http://www.internode.net/HoneyBee/.  If you have not been there and you are
interested in the subject, I invite you there now.  There is a tremendous volume
of material to be found from the links.

In spite of all the sources and links listed there, I must confess, however,
that I have learned far more and far faster from the books listed on that page
than from all the web pages I have catalogued, the discussions I have read, and
the lectures I've attended.  (There is another book that I have lent or
misplaced as well, and maybe I'll be able to list it later).  I recommend the
books most strongly.  It's not that I'm ungrateful for the advice and help I
have received on the net and this group. The encouragement and pointers received
here have been invaluable to guide and encourage, but there is no substitute for
the knowledge crammed into those books.

Interestingly enough the books I mention were written early in this decade, and
there does not seem to be much new since then -- that I have been able to
discover.  Europe has had varroa for several decades now, and the Europeans have
tried pretty well anything imaginable.  The 'new' ideas in North America are
pretty much old hat in Europe. It will be interesting to see what the big
breakthrough will be.  I know it's coming...

allen
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