If you go for the larger radius that gives you about 60 square miles to  play 
with. My inclination would be to have a larger number of small apiaries -  at 
least it gives the back a rest between apiaries. 
 
Your bees will be in competition with those already in the area. You don't  
say what the area is like for forage throughout the season.  If you have  more 
hives than there is natural forage, your bees will be stressed with all the  
attendant problems, and you will have to resort to artificial feeding which  
brings more work and expense and the risk of contamination of next year's  crop.
 
I suggest you read Bailey on the optimum number of hives kept in an  area.
 
Chris



   

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