On Thu, 14 Dec 1995 11:02:54 -0500, Jean-Pierre Chapleau wrote:
 
>To keep with the same thread, I am curious to know at what specific time the
>beekeepers shut the upper entrance in the spring and force the bees to use
>the lower entrance.  What motivates the choice?
 
For example in my case it is a daner of bee losses during the active
season when it comes windy or stormy weather and upper entrances are not
sufficient to accept the massive flow of returning bees. Lower entrances
also help to direct bees to raise brood in lower parts of hives.
Vladimir Ptacek