There were some trials in Maine of BO bees in blueberry fields. I attended discussions of the results by the researcher- who was a strong proponent of solitary bees- and my conclusion was they are good pollinators but only for small scale pollination. They cost a lot more per acre to maintain, especially if you are a large operation. Often, in studies like the one I heard, costs are all relegated to material without figuring in labor, the real driver of costs. I figured in labor and numbers of solitary bees to cover a large operation and it gets expensive quickly. For a small operation, BO or Mason bees are great, especially for apples. They do a better job on them (and several other fruit trees) than do honey bees. But, one hive of honeybees trumps the BO bees just by sheer numbers. That is what was shown in the trials in Maine. The did a great job on the blueberries, but to cover hundreds of acres you had to have honeybees. The cost difference made it no contest. And for someone like me, with fruit trees and vegetables (pollination was the reason I started beekeeping), there is no good reason to create a solitary bee presence, first since it is already there and second, that my bees do an excellent, albeit inefficient, job of pollinating all I grow. I was responsible for the upkeep of USN ships in the Pacific. It was interesting that we paid the same for a job in a yard that would use five men as for the same work in another country which used one. Labor costs canceled out any benefit. The quality was the same. But the other benefits were not. Sailors liked the inefficient yard better because their own paychecks bought more in the country. Great liberty port. But back to bees. For honeybees, the benefit is honey, which makes any desire to shift moot, since it is an income generator, pays for the bees and sweetens my cereal. Bill Truesdell Bath, Maine