>  Is there any research on bees being necessary for avocado pollination?
 
Once some years ago I did a talk on "The Sex Life of the Avocado".  I
still remember the opening line:  "Avocados exhibit a protogynous
dicogamy with syncronous daily compementarity".  Blank expressions...
 
And then went on to put it into 'normal' words...
 
Protogynous - the female flower comes out first
Dicogamy - each tree produces both male and female flowers
Synchronous - the male/female flowers open at the same time each day
Complementarity - when one type of tree has the male flowers open,
the other type has the female flowers, and vice versa...
 
So yes, there are Type A and Type B avocado trees.  And best
pollination occurs when you have a mix of the two.  But it isn't an
absolute hard and fast rule, at least here in NZ where the evenings
are a bit cooler than in Calif where the orginal research was done -
that cooler evenings breaks the absolute open/closed cycle somewhat,
which means we still get fruit even if there isn't a tree of the
other type nearby.
 
  (\           Nick Wallingford
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