Hello Ted,
 
Here is my 2 cents worth.  I pollinate almonds in northern California, pears (and sometimes peaches and apples) in southern Oregon and cranberries on the Oregon coast.  I am running about 100 colonies at the moment.  
 
The rule of thumb when pollinating  orchards is 2 colony per acre, with many athorities recommending  more.  I have found apples and peaches attractive for the bees and good for them, the peaches being a bit earlier then most of the fruit.   Bees (and beekeepers) seem to do better when the bees are put together in larger 'drops' of 12 to 24 hives in almonds.  This has been  verified in studies done at the University of California and is contained in the "ALMOND POLLINATION HANDBOOK" by Joe Traynor, Kovak Books, P.O. Box 1422, Bakersfield CA., $4.00.  This little book has good information for both the growers and us beekeepers.  It is well worth getting.
Dennis Morefield
Sideline Beekeeper, Oregon, USA
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