Hello All

I thought I'd wait a while before pointing out a few things that might help
put things into context and reflect my own understanding of the problem.  We
now have some pretty good response -- I'm hoping for lots more -- so I feel
okay about butting in here with some clarifications.

I'd like to thank those who took the time to really consider the question.
We've had some really good comments, and some that reflect various degrees
of misunderstanding, possibly because I assumed that everyone knows who I
am, what I am doing, and what I have done, and in other cases, because some
simply did not understand the question.

My apologies if I did not spell things out as well as I might have.  (All
our procedures are well documented at
http://www.internode.net/honeybee/diary/, but I don't know who would want to
read all that stuff).
---

First, and perhaps most importantly, this test was not done in isolation or
in an information vacuum.  I was testing bees that I have been managing,
testing and treating in a professional, thorough, well documented, and well
understood manner.  We have been constantly testingand treating where
indicated in the past, and I had little reason to expect trouble.

Second, I had specific limited goals in mind:

* I was pretty sure that my varroa levels should be low, but was aware
  that resistant mites can appear at any time and am keeping an eye out.
  Even a superficial sampling should spot a serious breakout with some
  reasonable certainty.

* I wanted to check for any gross failures in our treatments.  Our
  tracheal treatments were by the 'blue shop towel method', which by
  all accounts is a very good method, but we had only put on one treat-
  ment this spring and I wondered if there were any serious problems.

*We seldom have nosema problems, but the test was an easy add-on
 and if there are any gross problems this can give an early warning.

* I wanted to get an early fix on winter loss.  By this time, the poorest
  colonies are dead (some were nearly dead when wrapped).  This count
  gives me an idea of whether I need to plan heavy remedial action in
  spring or can count on reasonable survival.

Other relevant points:

*  We have been practicing IPM since before IPM became a buzzword.

* Our past experience has shown that there are a range of mite levels
  within colonies in the same yard, and that if there is a problem only
  a few colonies will be really bad.  Others may be almost unaffected.
  Thus the sampling of every colony.  We also wanted to count the
  dead, and therefore had to glance in every hive.

* We have also observed that what happens in one yard is usually not
  very different from what is happening in several others.  Thus our
  decision to sample about 1/6th of the yards.

* Our wrapping method allows us to take a few bees from each hive with
  almost no disturbance. We do not use hard covers, but rather a quilt
  (pillow) that can be gfently peeled back to reveal the edge of the
cluster.

* The gathering of samples took less than two days and 200 miles of
  driving (one person).

* Only 20 bees from each yard sample (totalling typically 175 bees)
  were actually pulled apart for examination.  The varroa shake was
  done using all 175 bees, however.

* The balance of each sample is preserved in 70% alcohol in case of
  further need and will be spot checked by another independant lab.

* My partner and I own the lab that did the lab work.

* We do not expect such tests to protect us from losing some individual
  hives. We are prepared to take calculated risks and consider some
  minor losses inevitable.  At some point the cost of identifying and
treating
  such losses exceeds the savings and moreover, testing and treatment do
  some damage in themselves.

*  We are not testing to know if we have varroa or tracheal.  We have them.
   What we need to know is whether they are getting out of control in the
   operation at large or in any particular area.

* We found zero levels.  If we had found even one mite, we could have
  zoomed in for a closer look by doing lab work on more of the bees and
  returning to the yards nearby -- or all the yards.

Again, I thank those who gave opinions and facts from various perspectives
and particularly thank those who made an attempt to apply mathematics to the
problem, but let's not quit here.  I think there is a ways to go yet on this
before we have explored the question fully.

If there are some factors I have neglected to give that are important, just
ask.

allen
http://www.internode.net/honeybee/diary/