This is likely a newbie/dum question, but if Varroa is endemic in the U.S. do we have to do a sugar shake or alcohol check? Of course, unnecessary use of pesticides isn’t great, but it sounds like Varroa is a given…
What do you think about automatically treating (oxalic or formic acid?), maybe in late summer?
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No dumb questions here, and that is a very good one! To my mind, there are several reasons to do a count:
- You don’t want to treat, and you want proof that you need to do it before starting
- You have already treated and you want to know whether it worked, or whether you need to repeat or continue for longer
- You are worried about resistance to the treatment you have chosen (a subset of number 2 above)
Depends on where you are starting from. I treat established colonies at least twice a year - Spring and late Summer (March and July/August). I will often do a count in Fall (September/October) and then decide on whether to treat again at that point. For new packages and nuclei in the Spring, I don’t treat until they have filled a brood box. Treatments can make them abscond (yes, it has happened to me), so I like to let them settle in first.
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I’ve been mulling over this very question myself as I fine-tune my Varroa strategy. I’m in my fourth year, and since the beginning I’ve been applying two automatic oxalic (dribble) treatments per year - one in March and one in November - to ensure they start and end the year clean. During the in-between months I’d count each month and treat with formic when necessary. The last three years the counts inevitably dictated an August formic treatment. So starting this year I’m planning to make my August formic treatment automatic (though I’ll probably count at that time out of curiosity).
I’ve also recently read a suggestion that applying an August treatment can ensure that your soon-to-be-laid winter bees will be mite-free, which makes an automatic August treatment sound even more sensible.
Great insights from Dawn too.
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Really good advice - thank you Dawn and Brian! I see the value of checking for mites and will just have to do it.
Honestly (and embarrassingly), it is daunting to think about scooping up a cup of bees and putting them into a mason jar - but we will do it…maybe later this month 
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Honesty is great! I hate doing the counts too - I worry about hurting bees. So there are some “work-arounds”.
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This is the most expensive, but if you already have the equipment, you can do an “accelerated mite drop”
Oxalic Acid Treatments discussion - #28 by Dawn_SD -
If you don’t have that equipment, then you can build this one fairly cheaply, which makes scooping up the bees a lot easier:
https://www.beelab.umn.edu/sites/beelab.umn.edu/files/cfans_asset_317462.pdf
Using OA when brood is present isn’t efficient. Your early season treatment might be better as something more beneficial when brood is on the up.
OA isn’t the only method for treating Varroa. Doesn’t penetrate capped brood and is more beneficial later in the season.
Treatments should be mixed, time of season specific. This also has been documented as minimising tolerance.
Too many people jump on the OA bandwagon as the Holly grail and only thing to use.
Study Randy Olivers extensive research he has priceless information on why, when & how.
Treating for the sake of treating is detrimental.
The UK has Varroa in most domesticated hives.
I’ve only treated 3 out of my 6 hives so far but all 6 have had min 3 mite tests more for the ones with a higher than acceptable mite drop.
Regular checks ensure I catch any increase in time to prevent major infestation and thats what kills most colonies coming out of winter.
That isn’t true for an OA trickle in late Fall/Autumn.
That is true for chemical treatments. But there is no evidence that Oxalic or Formic Acid treatments develop resistance in Varroa, even after many years of only using one type of treatment. 
No question
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Hi Dawn,
Randy’s website has some interesting findings based on his 15 years of using OA dribble method.
The below screen shot suggests the most effective time of year is when there is no capped brood (Nov-Dec).
I was on a Webinar with Randy Oliver yesterday through the Scottish Beekeepers Association and this question came up.
He had strong thoughts on using OA as a single method, times of treatment during the year and even made reference to it being a waste of time before periods of broodlessness and evidence of resistance.
I agree that OA shouldn’t be the only treatment, and understand that it’s only effective when the hive is broodless. But who in this thread has suggested otherwise? In my area (Ohio) the hive is broodless (or nearly so) from November till March, which is why the Honeybee Health Coalition recommends OA in November and March as part of their recommended pest management strategy for Ohio. And I use a different treatment - formic - in the summertime (as mentioned in my post).
I also provide an early brood break in spring. A comprehensive strategy in line with Randy Oliver’s findings
Maybe my bees don’t shut it down as efficiently as yours, but I am surprised by how much brood there is in Nov and March. Don’t know how much is there dec-feb though.
Summer seems mostly too hot for formic pro.
Doing multiple OA treatments 5-7 days apart seems to handle things pretty well as the OA is very effective on phoretic mites and doing multiple treatments catches most mites before they sneak into cells being capped.
This year I am planning to do a brood break (combined with requeening) between late-july and mid-august to zap all those mites before there’s capped brood.
I think we are talking at cross purposes here. 
I wasn’t specifically referring to an OA trickle. As you know, there are many ways to apply OA.
Using OA vapor when brood is present IS effective, if you repeat it at 5 day intervals. It then gets a chance to disrupt the mite breeding cycle. However, if you miss a treatment, or do one a few days late, it is much less effective. If applied correctly, it can drop mite counts by over 90%, even when brood is present. However, it isn’t very convenient when there are other choices.
I would only use an OA trickle when the bees are clustered. In my climate (and I think perhaps Randy’s too) the bees never cluster, and the queen never stops laying. I totally agree that in regions where bees cluster and there is a brood gap e.g. in Nov/Dec, OA trickle can be effective, but it isn’t sufficient on its own, because you can’t use it at other times of year. One treatment per year will never be enough to control mites.
Randy has also developed a method for applying OA using cellulose sponges. I have been doing this for a year now, and it provides excellent mite control year round. I put my sponges into the hive in Feb/March. The OA remains active for at least 2 months. I then monitor mites during the nectar flow and repeat the treatment around August. If mite counts were high in November, I would consider a different treatment, but that hasn’t happened yet.
There is absolutely no evidence of mite resistance to OA or formic acid, for that matter. They are physical methods for killing the mites, and there is no real way that the mites could biologically bypass their effect. There has be a big long term study in South America by one of Randy’s collaborators. He treated hives exclusively with OA over many years and found no reduction in effectiveness and no evidence of mite resistance. The study was well done and has been published officially.
I don’t mean to seem heavy-handed about this, but I just wanted to give details for any new beekeepers who are wondering about this subject. I know that you probably already knew it all, but sometimes these things aren’t obvious to new people.
I also need to apologize for a mistake here, which probably caused the confusion. I can’t edit my post now, but I meant to say:
That is only true for an OA trickle in late Fall/Autumn
The point being that an OA trickle is a one-shot treatment. You need there to be no brood, because you won’t be retreating. It doesn’t hold true for OA sponges or vapor. Sorry that my fingers didn’t type what my brain was thinking. Senility sucks! 
Like I mentioned earlier there are many beekeepers who only use one form of treatment, once a year, don’t fully understand the differences of treatments (it treats varroa so I’m all good).
Highlighting this on sites like this gives others an opportunity to see, digest, look into it themselves, agree, disagree and debate.
Treating for the sake of treating isn’t beneficial.
Yeah I’ve read some of those studies Dawn very interesting.
Not many people do extended treatment though. The results did have colonies with high mite counts that only dropped towards the end of his extended treatment studies.
If he had stopped treatment would they have increased or decreased? Thats more in line with what a hobbiest would do.
By his own admission he has no idea why they stayed high compared to others going through the same treatments then dropped.
It is promising to read about the use of specific ways with OA with supers on. I’m sure in time that will expand across other countries.
The original post on this thread proposed the question should we not just take it as a given and treat…
If you don’t know what you have, the extent or what measures to take, products to use its pretty non productive wouldn’t you agree?
P.S your never heavy handed 
its a discussion 