Hi Robert Over the last century, the thread on increasing cellsize is well documented but not part of most beekeeper's knowledge base. I wish that I had been more aware of it 25 years ago...Varroa or no varroa I would have tried to redress the balance. I have come to this discussion from a different angle...I have seen plenty of evidence that shows that cellsize affects bee size (although most of the experiments were striving for a larger bee)...See Beowulf Cooper's work about 25 years ago ISBN 0-905369-06-8 "The Honeybees of the British Isles" published by BIBBA. My reason to look at cellsize was to find a mechanism to discriminate against italian genes in my local Apis Melliffera Mellifera population. If at the same time I have a management technique that slows down the Varroa breeding process, all well and good (acarine or tracheal mite are not much of a problem in UK anyway). Too many people are arguing about this...Rather than conducting the trails themselves to broaden the data. You will get no help from the establishment or from supply houses...Try asking for 4.9mm foundation and see what assistance you get! I do not claim to have the answers nor these days do I have the resources or physical strength for large scale trials, but for my own satisfaction I will perform a few experiments...I have a feeling that there is much more in this than most people are prepared to accept. The trials are not difficult so how about some more activity? Perhaps Robert Mann is in a position to do some of the trails at his establishment? That would redress the ballance as far "evidence on its efficacy" is concerned. There is another aspect here that may be appropriate to New Zealand and their current "newness" of infestation. As each country has been invaded by varroa they have all adopted their own research projects into "Varroa". As a result the "Learning Curve" has been revisited two dozen times in about as many years. I would urge New Zealand to build on some of this work rather than duplicate it. At least as the latest to be invaded you should be able to learn by the mistakes that have been made by others. APISTAN will work as a "quick fix" while you get your act together. As regards a programme including several other chemical methods including thymol, formic acid. By all means make these trials BUT make your starting point the current "state of the art" even if it does mean accepting data from other sources. The physical control method (cellsize) needs testing in wide open spaces on large numbers of colonies. I would have thought that New Zealand had both requirements in abundance. All that is really needed is the audacity to "go for it". Regardless of my humble opinions, (you will find some more of them on my website), I wish New Zealand success in their venture. Best Regards, Dave Cushman G8MZY Email: [log in to unmask] Website...Beekeeping and Bee Breeding http://website.lineone.net/~dave.cushman ----- Original Message ----- From: Robert Mann <[log in to unmask]> > discussion on this list is interesting but patchy. > Our officials have been sluggish to respond to the emergency, > The idea of smaller-distance foundation is tantalising. I just > wish I could readily see more evidence on its efficacy. - > Robt Mann > consultant ecologist > P O Box 28878 Remuera, Auckland 1005, New Zealand > (9) 524 2949 >