Hi everyone,
 
I have gone on a 'reccy' for you all to try and track down the 'official'
line here in the UK (on the web) on varroa treatment as it relates to recent
discussion and will mean you can drop those calculators, as the work has
already been done.
 
I recommend you visit this site, set up by Chris Parker, if you want to know
more about varroa monitoring/calculations/drone method/varroa floors/ etc.
 
He has reproduced the MAFF (Ministry af Agriculture, Fisheries and Farming)
leaflet advising UK beekeepers.
 
It will answer all those questions I have seen lately on BEE-L.
 
Site:
http://www.airtime.co.uk/beekeeping/apiary/maff.htm
 
Madeleine Pym, London, UK