It's not quick and easy, but there is the method of placing a nuc with a
   small colony in it, next to the entrance of the "wall" colony, then
   covering the entrance with a cone of screen material, with a small
   exit near the nuc's entrance.
 
   Bees will leave the wall colony through your bee escape cone, but not be
   able to find the little entrance upon returning; so they will join the
   nuc colony (which is removed later when it has soaked up most of the
   bees, then the entrance gets sealed..
   I would imagine it would take several days to deplete a
   newly-established swarm, and 2 - 3 weeks to get rid of an established
   colony.
 
   Although this should work in spring early summer, I would hesitate in
   late summer, as the wall hive may have lots of brood and honey stored,
   and when that starts to break down and be eaten by little beetles and
   such, the homeowner might not be happy.
   good luck
 
 
   Kerry Clark, Apiculture Specialist
   B.C. Ministry of Agriculture
   1201 103 Ave
   Dawson Creek B.C.
        V1G 4J2  CANADA          Tel (604) 784-2225     fax (604) 784-2299
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