I do not think that two queen hives will be effective as a means of
swarm control.  However, they can be extremely effective as a means of
harvesting a bumper honey crop, and one need not produce a skyscraper
hive as described by Aaron.

It is well known that a hive with 30,000 bees will produce as much as
double the crop as a hive with 20,000 bees.  Some researchers say it
is impossible to produce a hive with more than 40,000 bees, and 30,000
is more 'normal'.  With a two-queen system one can produce a hive with
50,000-60,000 bees!

I know two comb honey producers who modified their boxes so they
produce two-queen hives 'side-by-side'.  Just a 1/4" divider board
down the middle.  The brood nest for each hive consists of two deeps
and two mediums, so each 'side' effectively has a single deep and a
medium, more than enough room for a brood nest.  Each side starts with
a new queen and a split.
When the flow commences, 3-5 comb honey supers are put on top, with a
single excluder.  So, the field bees intermingle in the supers.  Often
a total of 7-9 supers (per hive) are eventually filled on a good flow
such as sweet clover, but supers are removed when they are capped so
the stack never gets that high.

A similar two-queen system uses a deep and a medium for each queen, an
excluder between the queens and entrances on opposite sides.  Again,
supers are not added until the flow starts but when supers are added
the excluder is removed between the queens and put below the supers.
This quickly causes one queen to disappear, but by then all the bees
needed for foraging have emerged so the loss does not effect the crop.
 Again, the foragers intermingle in the supers, without apparent harm.

I have tried both systems on numerous occassions.  I almost always get
swarming with the second system, but almost never get it with the
first.  Dunno why.

The only disadvantage is the equipment modification with the first
system.  Cut the slots for the boards all at the same time, before the
bodies are assembled.  The modifications are not hard to do.

Lloyd

-- 
Lloyd Spear
Owner Ross Rounds, Inc.
Manufacture of equipment for round comb honey sections,
Sundance Pollen Traps, and producer of Sundance custom labels.
Contact your dealer or www.RossRounds.com

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