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." [log in to unmask] For those interested in IPM you would probably enjoy thier catalog. John Spaulding [log in to unmask]