I do have a book to reccommend on the subject.
 
"Bumblebee Economics"
 
by Heinrich Bernd
 
It has quite a bit of information on breeding bumbles.
 
I'll look over that section of the book tonight and see if I can
summerize.
 
I've also purchased Bumbles for pollination from "The green Spot Ltd."
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For those interested in IPM you would probably enjoy thier catalog.
 
John Spaulding                                  [log in to unmask]