Hi Bob -

> Dee started in the same area but finally went smaller to find what she
> considers the correct size for varroa control (along with breeding and her
> strain of bees). Dee said the foundation was actually 5.0-5.1mm so Dadant
> retooled and now the 4.9mm foundation from Dadant is correct. I am putting
> the above down from memory and very fast. Barry correct me if I have left a
> part out or have something incorrect.

Basically correct. The decision to make 4.9 the correct size had more to do
with results than with some book saying this was the magic size. Their
original understanding of the old literature was that 5.0-5.1 would be a
middle (average) size for the bees, so they retooled their entire outfit to
this size. While this size kept their hive numbers from decline, they were
not able to get much of a honey crop due to the secondary diseases
inflicting the bees. They retooled again to the 4.9 size and this time found
that these problems cleared up and production of honey went up too. (This is
an understatement from what I'm hearing is happening this year)

So yes, the size they consider to be correct for  varroa CONTROL is 4.9,
which they and others feel is still well within the RANGE of documented
sizes mentioned in early writings.

Breeding is also very important. We must remember that bees have also been
selected by man over the years to fit enlarged combs. As Dee says, the bees
must also be given a chance to adjust by their own selection for what, in
their genetics, fits the smaller cell size the best. This will happen over a
number of generations. I'm sure this is not a popular thing to promote or
say with the breeder crowd. I can understand the ramifications.

Strain of bees I don't think is an issue in their method. Whatever strain
comes to the forefront of any particular area, after working the bees down,
are the ones to work with. The hybrids will quickly fade out.

Regards,
Barry