Bob said: > On a final note if we move to controls like formic acid gel (or even liquid > formic acid) the fumes will sink from the hive (heavier than air) through > the screened bottom board without controlling varroa (reported at the 2003 > ABF convention by the makers of "mitegone " formic acid pads). I had this concern about my thymol treatment when I started installing OMFs last year. However, initial results show 19% overall winter losses, but only 9% on the OMFs. I am not claiming any sort of scientific validity for these results - too many variables - but I think that it does suggest that there was not major problem with the thymol vapour being lost through the OMFs. Peter Edwards [log in to unmask] www.stratford-upon-avon.freeserve.co.uk/ :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: -- Visit www.honeybeeworld.com/BEE-L for rules, FAQ and other info --- ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::