> The problem with Klartan is that it is not available in a form tested > and approved for use in beekeeping. I am not sure what the laws and regulations are in the Philippines, but Klartan and other formulations of fluvalinate *have* been tested by beekeepers worldwide, and used widely. Whether such testing and use has been scientific or wise or legal is open to debate, but I suspect that Western European and North American beekeepers are newcomers to this problem -- and also very much in a minority. > It is thought that beekeepers in Italy used a liquid agricultural > formulation of Klartan, absorbed on a porous piece of wood or similar > to combat varroa. I don't think there is much doubt that just about anything that can kill mites has been used and is being used with varying degrees of success -- and governmental acceptance -- today in large areas of Europe and Asia. The methods of application are many, and range from strips of paper or wood, to drops of chemical placed on the hive floor, and to aerosol sprays in combination with acetone and other carriers. In China a fluvalinate varroa strips are sold in a nice package that contains something that resembles a cloth strip. It promises to get rid of varroa 'Once and for all'. See http://www.varroa.com (Is the server still working or has it disappeared behind the Rice Curtain?) --- As an aside: I sat with Mr Wang, the proprietor of the firm that makes it, in a cafeteria at Apimondia and had no idea who he was until after when I read his brochure and saw his picture. My Chinese was as entirely lacking as was his English :) > Because there was no control over the amount > applied, this practise inevitably gave rise to resistance, not only to > Klartan, but to the whole class of synthetic pyrethroids including > Bayvarol and Apistan. This is often repeated, but is at best an oversimplification, and at worst a lie that those who sell a penny's worth of chemical for $2 don't mind having repeated often. There is a lesson to be learned here that will be lost if we misunderstand what happened and blame the beekeepers instead of those who should have been designing and supplying an IPM regime. It was well known *at the outset* that fluvalinate and related substances would have a life expectancy of about ten years if used annually against varroa unless rotated frequently with other different methods of control. After that time, resistance was to be expected to appear somewhere. This has been proven to be true in Europe and also North America. In both places. The first resistance was spotted in southern regions. We must also remember that varroa invaded some such regions long before other places. Italy is in the south and varroa control there is not the same kind of problem that it is in the northern areas where brood rearing is seasonal and varroa can often be controlled with one annual application. Therefore, multiple applications are necessary annually. No matter what method of application was used and at what dose, resistance was inevitable. Whether or not the resistance was hastened by the particular substance which was chosen and the delivery vehicle, we shall never know. The basic idea of using one type of control only was entirely responsible for the development of resistance. Governments, researchers and chemical companies let us down. Period. There *are* good reasons, however to consider carefully the advisability of using a raw agricultural chemical in a honey bee hive that produces food for humans. Safety, efficacy and legality are all concerns. In the case of fluvalinate, there are several significant points in favour of Apistan(r) compared to Klartan, etc. Apistan uses a less common form, fluvalinate-tau, a non-water soluble form that does not have an affinity for honey, (although, being oil related, it will enter wax to some degree). Apistan also has been tested and proven not to contaminate honey if correctly applied. This is extremely important if one is trying to produce honey for sale on the market. Buyers *do* look for contamination, and any residues can be reason for condemnation of a batch of honey or costly recalls. Other 'approved' chemicals may be no better -- or even worse -- than unapproved methods, but if there is a problem, you do have someone besides yourself to blame. > At the risk of repeating what has already been stated many times on > this list, stick to approved products, used according to the label. This is good advice. If you go wrong following your local mandates, you will have lots of company. Nonetheless, this is a worldwide list and what is the law and custom in northern developed countries may not apply at all in countries where there is no approval process or rules. allen http://www.rossrounds.com/HoneyBee/Diary/