>So what's some OTHER guy to do?  Run his own little experiment to
>determine what "threshold" seems to be reasonable for him in
>his location, with his bees?  Naw, he's gonna accept whatever
>number he finds first, as bet his bees, his crop, and perhaps
>his farm on a contextless scalar from someone with very different
>conditions from his own.

Yes, if the "other guy" is prudent he will test his own thresholds, using 
his own methods, strain of bees, in his own location, etc., and if he's 
rash he may accept whatever number he finds first and bet the whole farm on 
it.  

The value of the various published thresholds is in defining a range.  
Seeing a range of published thresholds helps a beekeeper to find a starting 
point.  If a beekeeper wants to minimize the risk of the published 
thresholds translating poorly to his circumstances, then he can begin with 
a lower number on the range.  If there are no signs of varroa trouble at 
the lower threshold numbers, he may decide that it's prudent to try a 
higher threshold.

>Hives can "crash" from varroa infestation
>before either one of them will even get around to looking at mite
>drop counts.

Sure they can, but they're more likely to die following the conventional 
treatment time (August in this part of the country), which makes a mite 
count at that time of year (or shortly before) most useful.  Moreover, most 
beekeepers aren't going to consider treating until the conventional 
treatment time anyway.  We can give them a means of answering a question 
they're not interested in (should I treat in June/July?), but it makes a 
lot more sense to begin by offering an answer to a question that might 
interest them (most beekeepers): I'm going to treat at such and such time 
of year unless you can convince me that it's not necessary -- is it 
necessary?

Your emphasis, Jim, on the rate of varroa increase seems misplaced to me, 
though.  If I told you, for instance, that over the last two months the 
rate of growth in my varroa drop count was doubling every month, what might 
you advise me to do in the field?  On the other hand, if you told me you 
took a one-time count in late July on your bees in North Carolina and your 
natural drop was 12/day, I could make a pretty good guess as to what your 
rate of increase was.  Based on that, I would generally advise you not to 
treat in August, because a normal rate of increase wouldn't put you over 
the over-wintering economic threshold.  I certainly wouldn't discourage you 
from taking another count in September to make sure your hive didn't 
experience an unusually high rate of varroa increase in late summer.  And I 
wouldn't discourage you from taking counts in April or May either.

But the pre-winter peak is properly the most critical question, and the 
reason I say that is because I believe the mite load that a hive can take 
through the summer without serious adverse consequences is much higher than 
the mite load that a hive can take through the winter without serious 
adverse consequences.  The high natural turnover in the bee population 
helps minimize a lot of the adverse consequences in the summer.  Of course, 
mite loads are typically increasing in the summer, so a tolerable mite load 
in May doesn't necessarily mean a tolerable mite load in August, whereas a 
tolerable mite load in September pretty well does mean a tolerable mite 
load all the way through March.  But I certainly wouldn't compromise my 
July honey crop because a hive was dropping 60 mites/day in late June, 
whereas 60 mites/day in September would, for me, justify immediate action.  
Similarly, I would expect 30 mites/day in early August to grow to 60/day in 
September, such that I would take action in August.

There are also more things that can happen (like swarms) that will 
seriously skew the data in spring and early summer.  Things are more stable 
in my bee yards by late summer, which makes it easier to foresee the 
consequences of a given mite load and therefore to put the data to better 
use.  Moreover, there are years (like 2006) where basically none of my 
hives ever reached threshold.  With no other indications of varroa 
problems, I'd be fairly comfortable with just one count in early August to 
reassure me.  If numbers are really low in May/June, as they typically are, 
I have a hard time seeing the point in taking extensive counts.

>They have bought into a policy of
>only worrying about Indians if they see 55 or more approaching.
>But they don't even LOOK for Indians until they are nearly
>done their journey, and ignore the different sizes of wagon
>trains they lead, some small enough to be wiped out by a mere
>dozen attackers.
>
>Does this sound like a fool-proof way to get the settlers
>to their destinations with their scalps intact?

I have several problems with your analogy.  First, the "fool-proof" 
standard is an absurd standard.  I want to make money with my beekeeping.  
Trying to save every last hive isn't the way to make money.  There's a 
point at which the cost of indentifying and 'saving' a small percentage of 
problem hives isn't worth the gain.  Secondly, if I'm still in Chicago, the 
likelihood of an Indian attack is slim enough that I can pretty well not 
even look for Indians.  If my hives are in danger of crashing in the middle 
of spring management, it's not going to catch me off guard.  And when I get 
to South Dakota, if I'm leading a wagon train that couldn't even fend of 12 
Indians, I probably ought to find another wagon train to join up with 
anyway, regardless of Indians.

>1)  You admit that varroa do not infest hives, but entire yards.

I know you have your theories for saying this, but do you have any data?  
Even informal data?  I can say I've seen hives dropping 300 mites/day next 
to hives dropping 2 mites/day.

Eric

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