Varroa control styles in Danmark

[Finman]

Questionaire 2005

Formic acid and oxalic acid

The questionnaires points out that beekeepers on larger scale are going for methods that are rapid in use. None of these beekeepers are using the time-consuming methods such as lactic acid spraying, queen exclusion or heat treatment. Also drone brood removal is very restricted in use (25%). Some of the beekeepers answers that drone brood removal is used under certain conditions, such as single colonies with high number of mites within the season. The beekeepers were also asked about the use of volatile oils. Presumably none are using this method since this kind of product is not well known in Denmark. The main varroa treatment is the use of evaporation of formic acid right after the honey harvest in August ? September and then a late treatment in October with oxalic acid trickling, combined with a spring treatment.

Formic acid is used by all beekeepers, but in different ways. The use of the kr?mer board is the most predominant method. Used by 60,0% of the beekeepers. The use of free formic acid is also common used. Several beekeepers remarks that the free formic acid is used only in nearby apiaries. The nassenheider evaporator is used by 15,0%.



Oxalic acid is used by all beekeepers except 2. Spraying of oxalic acid was used some years ago, but is not used anymore. Trickling is the dominant method. Evaporation of oxalic acid was only used by one beekeeper. This beekeeper used this method as the only treatment.

70,0% were producing nucs, to secure the number of colonies wintering out in the springtime. Several of the beekeepers pointed out that the production of nucs not are because of varroa, but solely to have a surplus of colonies in the springtime, in years with heavy winter losses.

Counting the mite downfall is not a big issue for the large scale beekeepers. 20,7% does never look for natural mite downfall. They can?t see the necessity. Their methods and strategy is satisfying. 60% are looking for mite downfall when it is necessary. But they never count mites. They look at the debris and make a very fast monitoring calculation ?situation under control" or ?situation might get out of control". Spot test are used. Several are only looking on sealed drone brood, opening a few cells.

60,0% claims that they have never seen damaged colonies or bees. 25,0% claims that they do have single colonies now and then, that have damages due to varroa.

65,0% do realise that the organic varroa treatment is more time consuming than the use of drugs. Several of the beekeepers haven?t answered the question, since they never have used drugs, and therefore can?t compare. Some of the beekeepers even claim that there is no extra time consumption.

The reason for using the organic methods is very clear. All (100%) are doing this to ensure honey as a clean natural product without any kind of residues. 50% are doing this due to a long-term strategy and 45% are doing it because concerns regarding resistance to drugs.

75% of the asked beekeepers have never considered the use of any kind of drug as a possibility, not now or in the future. This was underlined very clearly by the beekeepers in the questionnaire. 10,0 % didn?t know if they might change strategy.

http://www.biavl.dk/index.php?Itemid=50&id=114&option=com_content&task=view
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[Finman]

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Ireland seems to be out of practical methods

http://www.irishbeekeeping.ie/beehealth/fibkavarroa.html
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[Hivemaker.]

Nor do i count mites,better things to do in life than count mites,takes 2 minutes to see if they have many mites,and not much longer to get rid of them.

 

[BKF Admin]

Must admit that I have never counted them.

Thymol and OA if they have them or not.

 

[Bcrazy]

Sorry men but I have to disagree regarding counting mites.

Surely as part of IPM and Varroa control, a mite count must be undertaken to ***** the level of infestation. You only need to monitor three times a year, spring, when you harvest the honey and autumn. The reason why a count must be undertaken is so that the varroa mite population is kept below the level where harm is likely. This is why the OMF were introduced to allow the mites to drop out of the hive and collect on the tray beneath. It was thought that mites that become dislodged through grooming would be able to crawl back in to the hive from the floor.

Regards;

 

[Hivemaker.]

I appreciate what you say Bcrazy, but i do in fact keep quite good control of mites without physically counting each mite,the reason being i do not use varroa floors on the majority of my hives,in each apairy i have a few varroa floors which i use more to see that my treatment is working than anything else.Yes i know the mathematics from the varroa calculator. my reason is if two or three have mites on the floors,then they all will.My main way however of monitoring is by a drone comb in each brood box,this is also a way of removing a proportion of mites,but in spring if i find no mites in these combs,which i must say i do not usually see a single mite,then the next drone cycle i allow to emerge,as i also want plenty of drones,and so on. when and if i start to see more mites in this drone comb than i like the look of,i will act accordingly. I treat every hive as soon as the supers are off regardless,and longer than most.Also treat any swarms,and artificial swarms and the parent brood as it emerges, nucs can be kept free all the time. but even in the drone combs i don't count the mites,just act on instinct i suppose is the only word i can use.And it works. but i am sure you are correct with this counting for a new beekeeper,until they get an idea of varroa nos that they may have in the hives.

 

[BKF Admin]

How do you treat the swarms,with strips?

 

[Bcrazy]

Great post Hivemaker.
I understand your method and as you mentioned you have quite a few hives so your way in controlling Varroa suits your method of working.

I believe that beginners and beeks with experience should do everything in their power to combat Varroa and that includes mite counting. If the floor is spread with a thin smear of petroleum jelly then any mites that fall through will become stuck. Then take the tray indoors and do a count with a cuppa.
If there are a number of hives to do then spread the count evenly and keep records.

That's another point in beekeeping is Record Keeping. This is a must!
More on that later.

Regards;

 

[Hivemaker.]

Thymol,if its some collected swarm from who knows where,i wait until the queen just has eggs then treat.have also used sublimation of oxalic and strips when they worked,and formic. I like thymol best.

 

[BKF Admin]

Do you use a smaller dose for fear of knocking the Queen off lay for to long?

Can we swop recipes.

 

[Hivemaker.]

yes i do,any mites are only the bee's so only 24/48 hours works well.

 

[BKF Admin]

Just given myself a gold star for thinking that one through.

 

[Markbee]

I have never counted mites, dont see the point.

 

[Finman]

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After 20 years mites I have never calculated.