[Luv2beekeep]

When using an oxalic acid vaporizer how often should you treat the bees. Each week, every 10 days, every two weeks? What is too soon or what is waiting to long?

 

[JWPalmer]

Lots of information on Beesource about OAV. Optimal treatment is every 4-5 days until mite drop dead count approaches zero. Some treat weekly as I do when following a program. Anything less than every seven days is likely to prove ineffective at controlling the mites IMO. The bees are not affected by OAV so it would be hard, based on our current understanding, to over treat.

 

[dekster]

Well, it may already be too late if you haven't started yet... As for frequency up until now I was under impression that you can treat as often as you want (every 3-4 days), but this recent study from UoG shows that OA has the highest bee mortality rate among all organic treatments, so now I'm thinking of spacing treatments a bit more...

 

[JWPalmer]

Dekster, you may want to read the paper you linked again. OA was only tested as a dust mixed with powdered sugar and as a liquid mixed with glycerin. It was the glycerin/shop towel (ala Randy Oliver) application that had the highest bee mortality in this study. OA vapor was not tested. There are no reports that I know of, among those that use OAV, of any bee mortality, including brood.

 

[dekster]

Dekster, you may want to read the paper you linked again. OA was only tested as a dust mixed with powdered sugar and as a liquid mixed with glycerin. It was the glycerin/shop towel (ala Randy Oliver) application that had the highest bee mortality in this study. OA vapor was not tested. There are no reports that I know of, among those that use OAV, of any bee mortality, including brood.

Yes, but I asked Dr. Guzman (who was leading the study) if the same numbers (as dry OA powder) would apply to OA vaporization and he said -yes... He was presenting the findings of the study at our bee club meeting last week. Pressed again, he confirmed that there is no such thing as harmless treatment. Don't shoot the messenger...

 

[Luv2beekeep]

I have been treating for the last month and a half. I have been going every 5 days because after I pulled the supers it was like someone dumped a bucket of mites in half the colonies. I have been doing alcohol washes every two weeks before the supers came off and things looked good. I have talked to several bee keepers in the area and they all said the same thing. As soon as they took the supers off the mites exploded. I have them under control at this time but was just wondering if I was over doing it. Thanks for the comments. I will hit them again this Friday just to get them ready to go in the cellar for the winter before pollination. Thanks again.

 

[msl]

methinks a doc put there foot in there mouth:ws:

Treatment 1, OA dust, was prepared as previously described by
Emsen et al. (2007). Finely powdered OA dehydrate (Sigma–Aldrich,
St. Louis, MO) was mixed with confectionary sugar at a rate of
0.2 g of OA per g of total powder. In total, 30 g of formulation was
applied to each colony on a piece of newspaper (25 × 10 cm), which
was placed on top of the frames of the brood chamber.

They mixed OA in feed, and put 6 grams of oa in to each single brood chamber and suggest the bee mortality is the same as vaping 1 gram?
laughable, as is the fact that the untreated control hives only lost 20% over winter
the difference between the "best" treatment and treatment free was the death of one hive, that's not a study thats a small sample size as there were only 5
If I could take only 20%, heck 30% losses and be treatment free I would in a heartbeat.. and I would think hard about 40%
however.. that's not the real world

but yes.. there is no such thing as a harmless TX
yes it kills bees

yes it kills queens

sorce https://www.tandfonline.com/doi/full/10.1080/00218839.2015.1106777
kills brood
http://doorcountybeekeepersclub.org/site/wp-content/uploads/DCBC-Mites.pdf

but heck.. so do most treatments
you want to control swarming? just use formic as your spring TX... done

the internet legends around OA are as bad as the TF ones

 

[BenjaminM]

I am trying to put together a rough calendar for myself for NW Georgia.

I'm looking at treating in March and September, a total of (5) applications, every fourth day. TxxxTxxxTxxxTxxxT

And then treating in January, a total of (2) applications, every fourth day.

Wash in July and determine if it is warranted at that point.

 

[LAlldredge]

Very little rain meant I had to treat more frequently this year. My guess is- mites on plants were not washed off as easily so they were more persistent. Total guess. Prefer every 3 days until vanquished. Did an August series (6), then later fall series September 15th through October 7th (7). More than last year when we had more rain. Seriously hate mites.

PS- I would not be strict about a calendar. Spring for sure, August for sure and fall for sure but I would go more off of observation. I blasted them this year but also observed more pressure even from a hive that's more resistant.