I have 1,000+ colonies. I look for the old queen. It doesn't take that long.
I like to requeen with nucs. Only trouble is the extra equipment it takes.
So use the top brood box as the nuc. Remove the supers. Remove the top brood
box. Put unfilled supers back on the colony. Shake the bees from the top
brood box - either into the colony,  or on the ground in front of it. Place
an excluder on the colony, and the top brood box on it. Put the covers on.
Next day, remove the excluder, and replace it with a solid inner cover or
plywood or the like. Give the top brood box a caged queen. Have it's
entrance be to the rear. In three to four weeks, you'll have a nice nuc for
requeening the parent colony. It's where you want it, and field bees wont be
lost. The parent colony will often store some honey in the supers, because
you reduced the comb space available to them by removing the top brood box.
They will also better utilize the bottom brood  box. Did you ever notice how
a colony that needs a new queen doesn't do much in the bottom of the brood
nest? Lots of pollen and nectar. Scattered brood. This way the old queen has
to use the combs in the bottom. To unite the two colonies, remove the nuc,
remove the supers. Find the old queen and kill her. Place a sheet of
newspaper on the bottom brood box, and the top brood box on the paper. No
need for holes or slices in the paper. Shake or blow the bees out of the
supers and put the supers back on the top brood box.  Your colony is
requeened.
    About finding the old queen. I use a shaker box ( empty hive body with
excluder nailed on the bottom), if I can't find her on the first try. She's
usually in the bottom brood box, and only occasionaly in the supers.
 
Dale Q. Marmaduke wrote:
 
> How do the professionals with 1,000+ hives requeen.  They don't have the
> time to look for the queens.  What are the techniques of the
> professionals?
>
> Dale Marmaduke
> (jsut five hives and working for twenty)
> [log in to unmask]