I do not know whether a decoy hive near an apiary will cause a swarm.
     I do try to keep a decoy hive in the vicinity of my bees in case they do
swarm.
       I have not found that the pheromone has any effect on decoy hive
success.  (I have tried it during two different years.)
           I have for years put out decoy hives to try to catch swarms from
feral colonies in trees or buildings.
               The best decoy often is the stack of supers in the shed.
            Decoy hives:
            How big?     full hive body
                                shallow super
 
            How far from possible parent colony?
 
            How high off ground?
 
            Hanging by rope from limb of tree?
            Against trunk of tree?
            On shed roof?
            On ground?
 
            Bait?    an old comb?
                         pheromone?
Tim Sterrett
Westtown, (Southeastern) Pennsylvania, USA
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