> Surely that would seriously inhibit varroa propagation?

My impression is that the absolute size of the cells is not the cause of
inhibition (if any), of varroa since any honeycomb cells are *much* larger than
a varroa mite.  My understanding is that it is forcing bees into cells that are
a little tight that does the job, since there is less room for the varroa to
work, although I may be wrong and we do have some experts on the theory here on
BEE-L, and maybe they will elaborate on the mechanism postulated.

> Separately, what about "old" dark brood cells that have been
> contracted by cocoons? What "size" are these?

I seem to recall that the idea of significant reduction in cell size due to
cocoon build-up has been debunked.  Apparently the bees do remove the cocoons
from cells and the wall thickness does not increase significantly _from this
cause_.  Having said that, though I am aware of old dark brood combs that are
tough enough to withstand being stepped on.  I notice that the coping is
heavier, but does anyone have a study about actual wall thickness measurements
and dissection?

allen

http://www.internode.net/HoneyBee/
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