Allen,
 
There are quite a few people that run single BCs in the central valley of CA.
 Most that I know pollinate a great deal of the year and quite often don't
ever do any extraction.  They feel that they can maintain a good pollinating
unit this way.  It does in my opinion affect buildup of the hive.  I run in
11/2 BCs for this very reason.  They usually are pulling frames of brood for
nucs quite often keeping the nest clear.  We usually are concerned with
actual frames of bees and brood when pollination contacts are made.  The
trend of paying based on frame count is here and ever increasing so the
stipulations on boxes doesn't come up often.  The method of BCs changes for
some depending on if they run for a honey flow or not.  You are going to find
that there are many different ways that CA beekeepers run their hives.  I
don't think that I would say that they are now running generally in single
BCs, it is quite common though.
 
Brian Tassey
Alta Apiaries
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