Hello Mark and All,

I am probabbly not the person to respond as I have only got limited
experience using slatted racks.

 I have  read most of what has been written about slatted racks  and Dr.
C.C. Miller, Carl Killion and John Brant   swore by the slatted rack.

I understand the reasons  Dr. Miller states in his book ("Fifty years  among
the bees")  why he found the  racks useful but never enough to spend the
money to incorperate  the racks into my outfit.

> 1/...  Has anyone noticed a marked effect in either honey production
and/or  as part of their IPM program?

My trials  with slatted racks were before varroa so they were never part of
an IPm program. Honey production varies from hive to hive so I did not
notice a difference in production. I did notice that none of the hives with
the slatted rack swarmed.

> 2/...  As I use screened bottom boards on all my hives, does the slatted
rack interfere with mite drop; by this I mean, does the rack get in the way
of the falling mite and save it from getting trapped below the mesh and
thus reducing the total number of mites trapped and effectiveness of teh
screened bottom-board?

I can't see where the slatted rack would hinder mite drop to any great
extent but a few might catch on slats on the way down..

> 3/...  What is the underlying concept of the slatted rack and how does it
work?

Dr. Miller (inventor) felt the  slatted rack allowed cluster space under the
brood nest, better ventilation, less comb gnawing and more brood nest.
Better wintering is also claimed but mostly by later beekeepers.

There are two styles of slatted rack of which I have tried both. The
original design which is still available from Betterbee and the new style
which was improved by Carl Killion in 1950 which is also avilable from
Betterbee.

Both Dr. Miller and Carl Killion were large scale producers of comb honey .

 A couple large migratory beekeepers use two deeps and a shallow super. The
shallow super goes below the brood nest for most of the year for cluster
space. Those beekeeper friends claim many of the same benifits claimed by
the users of the slatted rack.

Sincerely,
Bob