My very unscientific trial of essential oils (oregano, spearmint, and lemongrass) was a bust with three out of four colonies dead. The survivor was a Mike Palmer Varroa resistant queen, so it had a leg up on the carniolans. I was asked to speak to a local beekeeper group and took a rough appraisal of losses over the past winter (mortality has been high in Maine this winter with many loosing all their colonies). Those who treated with formic acid and fumidil lost no colonies. Many who treated with apiguard or other thymol based treatments, like my essential oils, lost all or nearly all their colonies. One who treated with formic lost a colony, but they did not use fumidil. The treatment championed by Medhat in Canada works in Maine also - formic and fumidil.. Just about everything else did not. Bill Truesdell Bath, Maine *********************************************** 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