> Peter wrote

> >Is this correct?  If so, what is the explanation for bald brood before
> we had varroa?

Denjis wrote

> Some posts from New Zealand indicate that bald headed brood can occur
> without any obvious mite infestation.

I have written on another list that I see it regularly here in Australia.
It can sometimes be associated with wax moth larvae but most of the time
there is no observable reason why it is happening.  I have examined the
cells by pulling the larvae out, finding nothing untoward, and I most
definitely do NOT have varroa.

I have seen it for years and it was always put down to some genetic trait as
we here in Australia had been getting breeding stock from the USA for many
years prior to 1983.
Spring seems to be the main time to see it although autumn (fall as you call
it in the northern hemisphere) is another common time.  I happened to see
one of our breeders with some baldy brood yesterday.  About 4 cells in
different places, so it could no have been a wax moth larvae.  For wax moth
it is usually cells that linked together with raised edges.

Years ago when I first saw it I was working with our State Department as an
Apiary Inspector and the common thought, other than genetics, was that they
were raising so much brood in spring, with the expansion, that they didn't
have time to cap it.  I wasn't in favour of this theory but throw it in for
what it is worth.

So this baldy brood is certainly present in hives over here and is not
associated with varroa in this part of the world.

Trevor Weatherhead
AUSTRALIA