> What is the exact role of  drone pheromones in a colony?  Is this what
 > guides the workers to feed the grubs and then to seal them in at the
 > correct age?  If so would a artificial source interfere with this?

There was some discussion of the functions of pheromones at Apimondia.  FWIW,
the proceedings is available in a handy book that was distributed to all the
attendees and contains the entire transcripts of some talks and précis of
others.  Pheromones of bees are apparently cues to varroa.  One such pheromone
is the one that brood emit when ready for capping.

1,000 extra copies of the 'Proceedings' were printed and some are still
available for about $15 CAD (as I recall), from the Canadian Honey Council at
http://www.honeycouncil.ca/ .  I imagine that booksellers like Larry might have
a few copies too.

FWIW, Kenn Tuckey, our Alberta government Apiarist reported putting one
interesting fact from Apimondia to use.  After the meeting he had an opportunity
to be looking in a hive which showed no signs of varroa and had no drone brood.
Remembering a lecture we had attended, he uncapped one worker cell that was
taller than the rest and found varroa in it.  I believe he repeated the trick
again later.

The principle in use here was that varroa foundress mites questing for cells use
the height of each cell compared to surrounding brood as a cue to select the one
they will enter.  They prefer taller cells and enter them preferentially.

allen
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