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  • Oxalic acid time. What do you plan to do?

  • Honeybee pests and diseases.
Honeybee pests and diseases.
 #1498  by Jim Norfolk
 09 Dec 2018, 18:24
Its approaching the time of year when brood is minimal and many people apply oxalic acid to reduce Varroa levels before spring. There are a number of options: trickle or vape; remove remaining brood or not; do it before or after Christmas; use Api Bioxal or something else. What do people plan to do?

I have put ekes below the bottom box in my WBCs to allow room to insert a Varrox from the rear of the hive without damaging the plastic covered mesh floor below or the bees above. All I need to do is remove the lifts and off we go. I don't remove brood since everything is sealed up and I don't like to disturb the bees more than needed. Having both vaped and trickled over the years I am convinced that vaping results in less damage to the bees and higher levels of brood in spring, compared to trickling. On the other hand trickling is safer for anyone not happy with vaping. I usually wait until after Christmas but this year I plan to treat before the solstace. I will be using Api Bioxal despite its problems unless I can find another approved product. What else is available and legal?
 #1500  by NigelP
 09 Dec 2018, 22:24
Jim Norfolk wrote:
09 Dec 2018, 18:24
What else is available and legal?
And there wherein lies the big problem. The legal stuff leaves a horrible gummy residue in your vaporiser whereas the non licensed stuff doesn't.
 #1504  by AdamD
 10 Dec 2018, 10:18
In the past I have trickled between Christmas and New Year. Mite drop has been variable - and some of the nucs don't have the capability of monitoring so I have always just treated anyway.
However I now have a vaporiser and a battery so I have the option of vaping and I've got some old oxalic acid as well as some Apibioxal so I have a choice. Apibioxal contains Oxalic Acid, sugar and an anti-caking agent. So it's err... Oxalic acid plus the stuff that makes the pan of a vaporiser sticky.

I understand that if you use oxalic acid and don't tell anyone, then come spring no one could actually tell that you've used it.
 #1511  by Patrick
 10 Dec 2018, 20:39
I still trickle rather than vape.

Partly because I have never invested in the kit, partly because I haven’t got floors with entrances large enough to use the kit (good idea about the eke) and partly because I am confused about relative efficacy.

I had gone with the very high figures suggested by Sussex a while back but some of the users on here suggest that is not always acheivable or at least needs repeated applications, which takes the gloss off a bit for me. If

So maybe like so many things there is no cut and dried answer and you pays yer money and takes yer choice.

I do struggle with the broodless period tho, it’s so mild usually I doubt many colonies in the South have much of a broodless period, so I will just go for it in early January.
 #1512  by NigelP
 11 Dec 2018, 09:10
To clarify, repeated vaporisation's at 5 day intervals are for periods when brood is present. You need to keep hitting the mites as they emerge from the cells. The one off treatments are for when broodless.
It's highly efficient in MOST hives. For reasons not understood some hives just continue to drop lots of mites. God knows where they get them from.
I've just had two well treated hives suddenly start dropping large numbers of varroa this month!! They have been vaped with sublimox and will be vaped again.
Whilst generally OA vaporisation is efficient there are still a few puzzle hives. Robbing weak feral colonies is one possibility for the continuing mite load.
A lot also depends on the efficiency of how you vape, if underneath an open mesh floor you probably need to increase your dosage as a lot of OA is going to condense onto the mesh and not be spread around the hive.

Goes without saying you should always were protective masks when dealing with vaporised OA. This is not to everyone's taste and does deter some from using this method.
 #1513  by Jim Norfolk
 11 Dec 2018, 15:22
Patrick, Hasan Al Toufailia's thesis which is available on line at Sussex University suggests that January is too late where they are. Looking at their colonies over 3 years, he found between 9 and 52% had sealed brood in mid December but this rose to 100% for mid January with larger areas of brood in Janauary.

I am still finding quite large areas of dark cappings debris on my Varroa trays which I interpret as brood emerging. Hopefully that will have stopped in the next week or 2 and I can treat.
 #1514  by Patrick
 11 Dec 2018, 20:22
Aha, I had not picked up on the only repeated vape at times of emerging brood bit, that makes sense.

I wonder how reliable the concept about brood-less periods now are in practice with climate warming? The winters over the last 7 years around me Darn Sarf have been consistently warm and wet until early spring and a magic fortnight of no laying around the winter solstice just seems a bit speculative to me. Further Oop North could be rather different presumably.

I have noticed my chickens continuing to regularly lay noticeably later into winter than they did when I started keeping them. By now reducing day length and falling temperatures would normally have implied reduced egg laying, according to perceived wisdom but they haven’t stopped this year yet.

We all lapse into bee anthropomorphism now and again. This may be my first venture into the chicken equivelent. I wonder what that is called..?
 #1515  by Chrisbarlow
 11 Dec 2018, 21:52
I`ll be trickling until I pluck up courage to spend cash on a sublimox.

I agree about the broodles period. Without looking of course, I am not convinced in the Bikini wearing winter weather we are having as of late in yorkshire that my colonies are broodless.