Hello All, I raise Osmia lignaria (Blue orchard bee or the orchard mason bee) and would be glad to answer specific questions. Please search the University of Idaho site for the basics and I will help with specific questions. http://www.uidaho.edu Sincerely, Bob Harrison Odessa,Missouri Does anyone have experience of mason bees (Osmia spp)? I'm aware that trap nests are commercially available, and that they can be used for pollination. I'm interested in using them at an urban site in the UK, and I'd be grateful for any pointers. [log in to unmask]