>>[Transposing hives to balance populations.]  What are 
the important considerations in this maneuver?

Take care not to have the stronger hive's flying workforce overwhelm the weaker unit and kill the queen.  If I am doubtful about the outcome, I transpose about an hour before sunset to have some bee exchange before the night.  The next exchange will still be slow in the morning, picking up speed as the days rolls on by which time the weaker unit will have picked up sufficient bees that will have acquired its scent.  

I never transpose in the middle of the day.

>>How close do they need to be to each other or how far away from each other can they be?

They can be as close as next to each other but you will have a greater exchange of bees if the hives are at least several feet apart.

>>Is there a point at which the difference in strength of the two hives is so great that you would be weakening the strong hive more than the strengthening of the weak hive is worth?

This may only be an issue in the spring.  You don't want to depopulate a hive to the point where brood will get chilled at night.  I like to start transposing at the start of the regular swarming season.  I usually don't start transposing till 1st week in May.

>>Is it best to do this when there is a strong flow on?  

It's better but not really not necessary.  We usually have a pretty good flow in the spring when I transpose the production colonies but I will transpose nucs at any time in warm season.

>>Any important tips would be greatly appreciated.

I typically transpose after sunset when the bees have stopped flying and the cooler temps drive all the bees into the hives.  I close the entrances and move the hives around with a hand truck.  It's a rather easy task and it does not disturb the inner workings of the hives.

Waldemar

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