> Also, FWIW, sometimes fumagillin controls N ceranae well, other times not. > In two trials now in which I have drenched colonies weekly for four > straight weeks, nosema infection continued. I have seen the same thing. Myself and others had big problems with NC a few years back and the situation only seemed to improve when bees were shook swarmed on new foundation, deadout comb was treated with a mist Clorox solution and in about half the cases depopulation was the best solution *in my opinion*. Once a hive reaches a certain point recovery using Fumagillan can be a long process. > > We still have a great deal to learn about this parasite! I agree! A very complex issue. One problem I see is the commercial beekeeper thinks he will not see a N.C. problem if he has treated with fumagillan prophylactic in syrup. Not so. I have seen nosema problems and bees with high spore counts in hives which have been treated. The drench is a last ditch effort to get control. *in my opinion* does not produce excellent results. I have ventured the opinion a few years ago and my opinion remains the same. Depopulation and treating the equipment for "dink" hives which *will not* take syrup is the best move for those keeping bees for a living. Drenching four times ( or as label says as many times as needed) costs money for all but those doing research like Randy . More important if varroa control is not at a high level those hives develop CCD like symptoms. *If* the beekeeper wants to drench and attempt to turn those hives around varroa control needs to be a top priority . Sincerely, Bob Harrison Missouri Always dreaming of the place where corn dont grow! (and the weeds grow tall) "Where corn don't grow" Walon Jennings youtube *********************************************** The BEE-L mailing list is powered by L-Soft's renowned LISTSERV(R) list management software. For more information, go to: http://www.lsoft.com/LISTSERV-powered.html Guidelines for posting to BEE-L can be found at: http://honeybeeworld.com/bee-l/guidelines.htm