> sugar dusting as a means of 
> varroa management... didn't exhibit the
> efficacy that we needed if brood was present.

The concept of sugar dusting was introduced in 2000 by Fakhimzadeh, and I
have to take some blame for encouraging the use between 2001 and 2005 here
on Bee-L.  At the time, the hope was that removing phoretic mites would
work.  It didn't.

Harry Vanderpool even invented a machine to do the sugar dusting, as the
labor factor barely scaled above 50 hives.

By 2005, several of us "sideliners" were in possession of enough data to
show that it was simply not effective - apistan or formic acid and oxalic
did a much better job.  It did not prevent August post-harvest colony
crashes at all.  The experiment cost me about 50 hives.  (I do not apply for
grants or otherwise solicit, so my costs are my own.)

The "Dowda" method (dump on top bars and brush) circa 2005 reduced the labor
required, but also reduced the efficacy even more, as the fine 5 to
15-micron particles required to clog varroa tarsal pads were less common
when sugar was simply "dumped" rather than "poofed" as a fine cloud over
each side of each frame (the baby-powder bottle effect).  

In the mid 2000's, the ABJ articles on sugar dusting prompted many hobby
beekeepers to try this technique.  Because it did not control varroa
adequately, later ABJ articles offered sugar dusting as a complementary
treatment in combination with drone brood removal.  (But since drone brood
removal works fine all by itself, one can eliminate the use of the sugar,
and get the same results.)

Various controlled studies were published confirming what we had learned the
hard way - that varroa controls that only affect phoretic  mites simply do
not work.   In broodless periods, oxalic acid was far superior to trying to
sugar-dust, as a broodless period tends to be the start of clustering
weather.  But even caging the queen and creating a warm-weather broodless
period showed that oxalic out-performed sugar, hands down.

I feel that it is very irresponsible for beekeepers to actively evangelize
opposition to multiple published studies when such opposition can be fatal
to hives, and directly result in hobby beekeepers giving up the hobby.  It
is a scenario that those of us who take the time to teach and mentor see all
too often - the novice beekeeper is given false hope by an "easy answer"
that they so desperately want to be true, so they grasp at a website, a
discussion board posting, or a magazine article, and following the
suggestions therein, drive their hives straight into a ditch.  The
teacher/mentor is saddened by this, as a great deal of teaching and
mentoring effort "goes to waste" because of the misleading influences.  A
new beekeeper that loses his hives every year for several years in a row
gets discouraged, yet they will persist in grasping at "easy answers"
despite the prior failures.  It is unfortunate.  

> what I consider realistic constants 
> for mite reproduction rate and efficacy of drop

In this simulation, was the data based on the published data of Ellis,
Berry, Macedo, et al?  If not, what are the base assumptions?  If the
simulation is accurate, the colonies invariably crash, just like with the
old USDA Varroa Pop program.

             ***********************************************
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