Good advise I believe but how does one really know for sure there are no mites? I only have so much time to spend on a hive and I know that from sampling that the large majority are infested even though at allow level. I don't have the courage to assume because I didn't come across any during a sampling they don't exist. Or do I have the courage to assume that they have the tolerance to survive until a spring checkup. So you know what I did. Guess this is not much help to improving the tolerance line. The best I have been able to accomplish is a one time late fall treatment (second year). I do supplement this with selective drone frame culling which I assume is beneficial in raising a lot of drones that show a high ability, for whatever reason, to control mite levels. I happen to be a strong supporter of raising a lot of drones from colonies that show particular desirable traits. I know there is much more supersedure that occurs than what is usually acknowledged and to have lots of these fellows flying around can only be an asset. I have found that allowing colonies to raise lots of drones generally does better than those that are discouraged from doing so. Alden Marshall B-Line Apiaries Hudson, NH 03051 [log in to unmask] On Tue, 9 Dec 1997 13:09:47 -0600 "Excerpts from BEE-L" <[log in to unmask]> writes: >Reply-to: Discussion of Bee Biology <[log in to unmask]> >From: Al Needham <[log in to unmask]> > >>First I must say this again and again NO beekeeper should be treating >>for any kind of mites or any other pest or disease that does not have >>them. > >