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On the appiaries of Slovenia

The third part

 

Mr. Gregorije’s apiary on Kranjska Gora

 

The experiences of Kranjska Gora beekeepers in varroa treatment

It was very interesting to see how varroa is treated on Kranjska Gora. In this region varroa appeared several years later than in other parts of Slovenia. The beekeepers are well organized and they cooperate when they treat their colonies. Of course, this does not function ideally, but they tend to use medicines that do not leave trace in bee products and to treat their colonies according to a plan. Gregorije decided to use formic and oxalic acid only. They also have a plan of treatments during the year which is connected to the control of the number of varroa mites that fall off naturally.

Our hosts told us that the winter treatment with oxalic acid had been done on the 2nd of December 2001. On the same day some honey-sugar cakes were put.

Gregorije has a special kind of frames, two of which fit into one standard frame. He uses them for building drone comb. In one half of the standard frame is drone comb, while in the other is normal comb. This is not a great innovation, but it is worth considering that not all drone combs should be destroyed when fighting varroa, since a great genetic potential could be lost. That is why Gregorije destroys drone comb only in colonies which he is not satisfied with, while he leaves it in those with good queens. When this drone comb is sealed he takes it out together with the half frames and puts them in frames of a special hive which he uses for breading drones. This colony is treated against varroa several times and constantly fed to keep the drones necessary for fertilization in the hive. Gregorije opened the hive for us – it was full of drones and with plenty of food. He was emphasizing that he did not destroy drone comb but only removed it.

About varroa our host told us that if less than 32 varroa mites come out from winter, he does nothing until August. One should know the number of varroa mites in a colony in order to avoid an unnecessary treatment.

He puts 1 dl of formic acid in a vaporizer made in Germany. The acid evaporates 4 – 5 days and after that colonies are intensively fed. (It is interesting that professor Rihar used to emphasize the importance of feeding before treating bees with any vapor medicine.

On the 1st of September the second round of the acid is put (1dl)

In autumn and winter when there is no brood they use oxalic acid, whose efficiency is around 90%.

There is an agreement in the association that all beekeepers follow this process. This way every beekeeper is obliged to be successful in his work.

For treating swarms Gregorije uses lactic acid. He also uses sponge towels 20x12cm for shock therapy with 85% formic acid.

Oxalic acid is not allowed for use in Germany. In the bus, Mr. Poklukar informed the beekeepers that perisine will be forbidden in Slovenia next year, and advised those who used it to sell their honey since nobody will buy it next year if perisine is found no matter what quantity. Out of 15 samples of honey cumafos (perisine) is found in four.  Up to 0.1mg in 1kg is allowed, but only this year.

There are 1300 ecologic agriculturists in Slovenia. In Gregorije’s yard we saw how compost and biogas are produced. On all the apiaries that we visited that day we saw lemon yellow wax comb foundations. Speaking of the importance and perspective of ecologic beekeeping in Slovenia Mr. Poklukar said that everything produced is sold by 10 AM in two healthy food stores in Ljubljana.  

When making the solution of oxalic acid a special mask with acid filter should be used. This makes it difficult to work with. For dripping the acid plain little bottles with drippers are used. Beekeepers with AŽ hives add some thin hosepipes so that they could put the acid deep into the hives, while beekeepers with other types of hives do not have this problem.

Vaporizers bought in Austria are not that complicated in construction as the author of these lines expected. They work according to the Pascal’s law and are made of a rectangular container in which the acid is put, and which has marks for determining the volume of the acid. There is a drainpipe in the extension (similar to containers for water in bird cages) on which they put a piece of cardboard to stand vertically between two containers. The amount of vapor depends on the size of the cardboard. Our host mentioned that irregularly made vaporizer can cause the cardboard to absorb the moisture from the hive, which can come into the acid and decrease its concentration and effect.

Another kind of vaporizer is homemade and consists of a wooden square board with a hole in the middle which is put on a plastic tray. The size of the hole equals the size of an opening of a little bottle or jar in which the acid is put. The bottle is upturned together with the wooden board. In the other part of the plastic tray a cloth is put over which the acid evaporates.  

Our hosts who have a vast experience in using formic acid said that it was very important to keep the acid in a freezer before applying or it would evaporate fast and have negative effects.

1dl of formic acid is put in a vaporizer. It is best to put it in the middle of the hive’s height.  

For one Langstroth (LR) hive they use 3l of sugar syrup. 50ml of formic acid is used for one LR body, 100ml for two. That evaporates in 4 – 5 days.  

For short term treating 15ml of acid is used for one LR body. For two LR bodies on 30 degrees 25 – 30ml of acid is used while on 25 degrees 30 – 35ml is used.

What to say at the end? The day went very well; we saw many new things, new ideas and new acquaintances. The author would like to thank to his hosts from Semič, to Stane Plut, who organized the excursion and helped in everything, to Jože Sever for accommodation and hospitality, and to their polite and diligent wives Ana and Cvetka. A whole new report could be written about their beekeeping. A proof for that is the fact that Jože’s apiary was chosen for official visits during apimondia, and Stane’s apiary could be an example to much greater beekeepers, although Stane is a recreational. The author would also like to thank Darko Toplak, a beekeeper from Ruše near Maribor, who made this whole trip possible.