I run all solid bottom boards and full sun exposure. I'm going to assume their are queens as I would think I would have laying workers and drone brood if no queen. I've ran hygienic queen stock. If I lose these 3 hives I'll go back to treating with oa. This is my eighth year with bees with almost 50 hives a couple years ago. Too much work.That could be my issue, I was gonna hit em with OAV but was unsure on timing ( and needed to order OA). I have always ran small cell foundation and screened bottom and have been ok without treatment before, but I was also running survivor stock/ Russian hybrids.