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  • General Q&A, Bee chat and only Bee chat please
General Q&A, Bee chat and only Bee chat please
 #1299  by NigelP
 09 Nov 2018, 13:14
AdamD wrote:
09 Nov 2018, 12:42

My expectation is that varroa will develop a resistance to Apivar as they have with Bayvarol and Apistan.
It matters little if they do, they quickly loose it when not challenged by a particular pesticide. Just rotate treatments say three years Apivar followed by three years with Apistan. Pesticide resistance in varroa is energetically expensive and non resistant mites will soon outnumber the resistant ones once there is no more pesticide applied (this is why no longer than 6 weeks with strips is important).....and even if you have a few left the Dec/Jan oxalic acid dribble/vape should take care of most of those.
 #1300  by Jim Norfolk
 09 Nov 2018, 14:16
The good thing is we now have a wide range of anti Varroa products to choose from but in principle should we be putting insecticides such as amitraz (Apivar) flumethrin (Bayvarol) and tau fluvalinate (Apistan) in beehives? There are approved organic products available: formic acid (MAQS) and oxalic acid (Api Bioxal) which only leave residues normally found in honey. As well as thymol based products Apiguard etc.

I have found that MAQS given late in the year still works well and is less aggressive at lower temperatures.

Whatever you use either just do it or monitor Varroa carefully if you aren't going to treat.
 #1319  by thewoodgatherer
 12 Nov 2018, 09:49
One of my hives that was treated with Apiguard in September I have just done an OA vapour treatment.
This hive was still dropping 10-15 per day at the beginning of October having carried out the Apiguard treatment to the letter.
Last week on checking it was at 30-40 per day on the Varroa board so I treated with OA and had about 300 in the following 24 hours and its still at 100 plus per day. I would note this is the smaller of my hives and has by far the highest Varroa count the other being less than 10 per day at the moment. I currently have three options- 1) leave until next year, 2) Treat a further one or two times to cover any un-immerged brood or 3) Leave but treat again end of December/January. Be interested to know what others think?
 #1320  by Jim Norfolk
 12 Nov 2018, 11:13
thewoodgatherer, I have the same. Treated with Apiguard in August and daily mite drop fell to zero. Checked a week ago and an average drop of 8 per day. Vaped with OA and so far have 500 drop in 3 days, so a a bit less than yours. I have met this before and suggest two possible causes.

1. A mite invasion from another colony your bees have robbed out.
2. Apiguard did not kill enough of the mites and the survivers multiplied rapidly.

My plan is to continue to monitor and then do a second vape in a month's time when they are more likely to be broodless.

A drop of 30 to 40 per day is in danger of not surviving through to spring. If the count does not drop to near zero after a week or two, hit them again. It all depends on how much brood you have for the mites to hide in. Mites are said to be phoretic for about 11 days so a second treatment after a week or two will get most of the newly emerged mites before they can hide again.
 #1321  by thewoodgatherer
 12 Nov 2018, 13:28
I know the cause in this case and it was the Apiguard, I used Apilife var on the others and had much better results, this hive also had the higher count before and mite drop throughout treatment was poor in comparison to the others. I would happily blast away with the OA until near zero mites but worry about any negative effects of repeat application my only concern, at the end of the day the decision is mine. I do wonder though is Apiguard is losing its efficacy.
 #1324  by Jim Norfolk
 12 Nov 2018, 17:16
I have given a second vaping treatment at 2 weeks and all colonies survived with no problems. Looking at the numbers, on average, the first got 85% of the combined total drop for both first and second applications. This was at the end of December so the amount of brood would have been lower. Look back to the start of this thread and you will see that both Nealh and NigelP use repeated applications.

In my experience Apiguard gives very variable results. The bees must interact with it and remove it from the tray and spread it round the hive. It is also important to reduce air flow in the hive and have warm weather. If your hive is insulated you can probably ignore the 15 C minimum requirement.
 #1328  by NigelP
 13 Nov 2018, 08:47
Agree with Jim on this one. I never use Apiguard as I'm treating hives from mid-Sept and it's way to cold to work efficiently up here. I vape with a sublimox and generally 3 to 4 vapes at 5 day intervals works well for the majority of hives. Some are more difficult (and I don't know why) and just continue to drop large quantities of mites. Possibly robbing of feral colonies? I would have said inefficiency of vaping, but the sublimox fills the whole hive (double brood) with vapour and the 3 day mite drops can be enormous.
Worst case ended up with 10 vapes to get 3 day drops into single figures. No apparent damage to colony overall.
It's the 5 day interval you need to work at, as 7 days is too long and will allow emerged mites to re-enter cells.
I've now adopted a 4 vapes and you're out....or rather you are now on Apivar strips if you are still dropping a large numbers of mites.
 #1334  by Cable_Fairy
 13 Nov 2018, 22:24
I have been following the tread and decided to look at my Varroa boards this afternoon, and I seem to have a lot of the little beasts. I have cleaned both boards and will check them tomorrow, but I am unsure what to do if I have a lot. Would it be advisable to give them a treatment now (the weather forecast for the next week looks to be warmish) or wait till spring, I do have the following:- Apiguard, Apivar Thymol and MAQS, or should I get a Vape kit.
 #1336  by Jim Norfolk
 14 Nov 2018, 08:38
I think if you already have MAQS use it now. It has a short shelf life and so probably won't keep till next season. I have used it late in the year in colonies with high drops and subsequent oxalic acid treatment showed there were few mites left. It is stated to work down to 10C so depending on where you are it should be warm enough. Forecast here is 13 C today.