Hello Peter, Karen and All, Simple selection: >.If one selects breeders from hives with low mite counts, this trait > should be intensified I really believed in the late 1980's that simple selection would work, varroa tolerant bees could be found in all populations and the process could be completed within a few years. *Grandpa* beekeeper said simple selection would work. Dr. Shiminuki figured around 20 years. I believe now Dr. Shiminuki was correct in his hypothesis. Varroa populations grow and fall for many different reasons other than the bees themselves was what I found to be true. Varroa always infested the strongest of the hives first. Was the strongest less tolerant than the weakest I pondered? The strongest hives had the highest varroa loads so those were not used but when a weak (low varroa load) hive was fed continually the varroa load increased right away .. The lowest varroa loads were always the weakest and low production hives. Dr. Harbo realized the same thing and began to look closer at varroa reproduction. Without Dr. Harbo's discovery I would be still trying to select somehow from a strong hive with a slightly lower mite load than the strong hive next to it. To select properly I would need accurate information on the amount of brood (in all stages) and the population of the hive (possible but time consuming) . Many breeders found the daughters of those "simple selection" queens showed zero tolerance to varroa . The whole process was not simple as grandpa said and quite confusing as Peter pointed out. Dr. Shiminuki was correct in his 20 year prediction for simple selection in my opinion without Dr. Harbo's research. Sincerely, Bob Harrison