Re: Why not use Oxalic Acid?
Vaporising is better for the bees, but the dribble method is a whole lot easier for the beekeeper especially if there are a lot of hives involved.
Originally Posted by EasternIowaBees
When OA is vaporised into a hive it forms a vapour which distributes through the hive and condenses on everything, bees included. So everything has this fine acidic coating that kills mites, there is nowhere for them to hide, unless they are inside a brood cell. A vapour treatment done right will typically kill mites at a similar level to what Apistan would have to non resistant mites, for around 7 days. After that the kill rate rapidly drops off.
A dribble is different. OA is mixed with water, and only works if there is also sugar in the mix. It is squirted over the combs and gets spread around and also kills mites, however a lot more OA has to be put into a hive than if a vapour was used. Because the mix contains sugar, it is inevitable the bees will store some of it, and consume some of it. This can result in stomach problems for the bees, and if in food fed to brood, can kill larvae soon as they hatch from the egg, hence a winter OA dribble is known to have possible repercussions on spring brood nest development.
The reason a dribble rather than vapour is favoured by most commercial beekeepers, is the simplicity. A large batch can be mixed and a guy simply walks around with any kind of device that can squirt a measured amount of liquid each hive is treated in seconds, where a vapour treatment can be minutes per hive.
44 years, been commercial, outfits up to 4000 hives, now 120 hives and 200 nucs as a hobby, selling bees. T (mostly).