Beemaster's International Beekeeping Forum

BEEKEEPING LEARNING CENTER => DISEASE & PEST CONTROL => Topic started by: Bobbee on October 29, 2020, 12:47:18 pm

Title: Varroa checks
Post by: Bobbee on October 29, 2020, 12:47:18 pm
I just lost my first two colonies it is looking like to varroa. Moisture may have played a part however varroa mites I now believe were the main cause. Varroa and my not keeping their numbers down.I plan on being much more aggressive with checking and treatment next year even if I have to walk the 10 miles to the hives.
At the moment I have a couple of  questions.
 How soon should I check for mites after installing a 5 frame nuc?
Is it a bad idea to just assume mites and treat with OA ?I realize if I don't do a mite wash  I wont know if one colony has better varroa hygiene than the other. At this point I do not care.
 I just want to keep them alive and healthy.
Title: Re: Varroa checks
Post by: The15thMember on October 29, 2020, 01:16:40 pm
I lost one of my colonies to varroa my first year, and it taught me a lot about managing the mites.  Like most things in beekeeping, a lot of this comes down to personal preference and your bees in your environment.  I usually only treat when I see high numbers, but I know plenty of people who treat on a schedule.  Neither is wrong.  I personally feel it's a good idea to check mite levels periodically, even if you are planning on treating regardless, just so you can gain a feel for what your mite levels are like at different times of the year, and to make sure your treatment is working sufficiently.  I usually do sugar rolls (I prefer that method to the alcohol wash) at the beginning of the spring season, before my major honey flow, after my major honey flow/before any fall treatments, and after any fall treatments, and of course any time I think a colony has a high mite load (seeing lots of pulled pupae, bees that are shiny or with messed up wings, colony not building up well, etc.).  If it were me, I'd let the nuc get good and settled in, make sure you have an established laying queen, and then check for mites to know your baseline.  Whatever you do after that, I think, is up to you, as long as you do something.  Good luck next season, and don't be too hard on yourself about first year mistakes, we all make 'em.  :happy:       
Title: Re: Varroa checks
Post by: BeeMaster2 on January 24, 2021, 07:47:45 am
Fatima,
Welcome to Beemaster.
Glad to have you here on BeeMaster. Your English is really good. Feel free to ask any questions and chip in with your thoughts and experiences.
Jim Altmiller
Title: Re: Varroa checks
Post by: Beeboy01 on January 26, 2021, 03:24:55 pm
Bobbee, I treat on a schedule, March and late November for varroa mites but randomly hit the hives with a OAV treatment during the summer for a mite fall count. If I get more than 50 after 24 hours I'll continue the treatments for another 4 times just as a suppression move till the main treatment period in the fall. Looking at my records from last year I'm wondering if a third full treatment should be scheduled in late June or July during the summer buildup. Here in Florida we aren't getting the cold spell in the winter any more that caused a brood break with a reduction of mites come spring. I was a bit lazy on mite control last year, didn't do a full treatment in the spring and my hives took a hit because of it. One other thing that was really driven home to me last year was that any nuc either store bought or home made needs a full course of treatments, if not it turns into a mite bomb in the bee yard. I spent a lot of time splitting my hives but didn't follow up with any treatments and paid the price with lost hives and a small hive beetle invasion.   
Title: Re: Varroa checks
Post by: Bill Murray on July 17, 2021, 08:18:01 am
Quote
Looking at my records from last year I'm wondering if a third full treatment should be scheduled in late June or July during the summer buildup. Here in Florida we aren't getting the cold spell in the winter any more that caused a brood break with a reduction of mites come spring.
Beeboy, I have been trying to state this point  for quite a while. Im glad to hear someone else say it. For a couple of years I Made brood breaks by culling queens. Now I am on a treatment schedule. As for the nucs I agree with that also. Everyone I make gets treated, or as stated "mite bombs".
Title: Re: Varroa checks
Post by: rast on July 17, 2021, 08:42:42 am
I am currently treating with OAV.
Title: Re: Varroa checks
Post by: Bill Murray on July 17, 2021, 01:41:49 pm
First the disclaimer what I am saying is based on research I have done, the trials and tribulations I have fought through and basically what I found works for me. And I am talking Fl. I cant speak for anywhere else.

I got out of beekeeping for a while partly due to varroa. I was treatment free ( for my own reasons) and basically didn?t understand the mite. When OA came out I looked at it like a silver bullet. I used it for 2 years with varying effects, I thought. Year 3 showed me I needed to change course. I still use it but not as a standalone treatment. Here is why. First you have to look at how many capped brood are in the hive. If you are running double deeps and 50% percent of your frames are capped brood which should start in Feb/Mar here in fl through Sept./Oct. dependent on feed/pollen where your bees are at. After that it drops but never really enough anymore.

Anyway follow with me. The reason the brood break is so vital to what your trying to accomplish.

Treatment day 1 then wait till day 7 retreat. The problem is Varroa exiting their capped cells between days 2 and 6. This means you have 5 days of Varroa leaving their cells and more than likely will find another cell about to be capped. So those Varroa can hide across multiple applications of OA done every seven days in capped cells and you don?t even know they are there. Im not saying OA won?t have a positive effect on getting your mite load under control because you just killed 10-20 percent of the mites in your hive, but you only killed the ones in the phoretic stage. If you had a brood break meaning little to no capped brood, and all mites in phoretic stage the you would get 90% with the bees taking care of the rest do 1- 2 follow up treatments (dependant on mite drop) and be done. If you miss one treatment with capped brood, you can be back to almost square 1. Miss 2 well do the math. It can also be over used and bad for your bees. Here is good reading from Penn State.

 https://extension.psu.edu/methods-to-control-varroa-mites-an-integrated-pest-management-approach (https://extension.psu.edu/methods-to-control-varroa-mites-an-integrated-pest-management-approach)

With all that being said I always do post treatment spot checks. Never do pre-checks anymore. I just assume they are there cause they are and stick with the treatment schedule I found works for me.
Title: Re: Varroa checks
Post by: rast on July 18, 2021, 08:59:20 am
That is why I use a 3 day treatment cycle, 7 times. The OA "dust" supposedly remains viable for 3 days on the comb. No different than leaving Tactic or Amitraz in there for a month and a half. I also use about 2 grams per deep box.
 What I do from doing the math like Bill did, not what I am telling you to do.
   
Title: Re: Varroa checks
Post by: Bill Murray on July 18, 2021, 09:23:57 am
please elaborate on the OA dust. I am always open to trying a new strategy.
Title: Re: Varroa checks
Post by: Ben Framed on July 18, 2021, 09:51:52 am
Quote
That is why I use a 3 day treatment cycle, 7 times.

I am of the understanding a three day treatment cycle is good for for optimum results as well, with OAV.
Title: Re: Varroa checks
Post by: rast on July 18, 2021, 02:25:55 pm
Bill, the "dust" is my description of the OA particulate that the bees fan around in their hive when we treat with OAV. It is actually a solid and not a liquid vapor that settles on them and the comb.
Title: Re: Varroa checks
Post by: Bill Murray on July 18, 2021, 02:55:16 pm
Thanks for that. I thought we were going somewhere else.

Also how long have you been on this regiment. and how many time a year are you having to treat? If you dont mind.

Title: Re: Varroa checks
Post by: rast on July 18, 2021, 09:24:50 pm
Since spring of 20. I do the 3 x7 in Jan and July/August, same as I used to do the 5 x 5.  Count them in Sept. I also hit them monthly in the winter. I am currently down to ten hives (9 by this next weekend) and took me 45 min before church to treat this morning.
Title: Re: Varroa checks
Post by: CoolBees on July 19, 2021, 12:48:13 am
... Treatment day 1 then wait till day 7 retreat. The problem is Varroa exiting their capped cells between days 2 and 6....

I also do 3-day treatment cycles with OAV, for exactly the reason you state. Only, I usually try to treat 9 times (27 day total).

I did mite counts and sticky board drop counts on every hive during treatment - for 2 years. I collected all the data. Based on that data, I now: treat in August (once yearly) & don't count mites. This is what has worked for me, in my area. My bees don't get a brood break due to winter, but they do have a dearth from August till November.

My average mite drop counts would look like this (counted on the 3rd day after each treatment, just prior to the next treatment):
900
900
900
450
300
300
280
320
18

As you can see, the last 2 or 3 treatments seemed to catch a goodly qty of mites, before the drop counts really fell.

I know they say that OAV "stays effective" for 3 days, but my notes showed very little increase in mite drops after about 30 hours post-treatment. Suggesting to me that efficacy drops off quickly.

My data definitely has proven - to me - that a 7-day OAV treatment cycle would not work. Fwiw.
Title: Re: Varroa checks
Post by: Ben Framed on July 19, 2021, 01:03:21 am
... Treatment day 1 then wait till day 7 retreat. The problem is Varroa exiting their capped cells between days 2 and 6....

I also do 3-day treatment cycles with OAV, for exactly the reason you state. Only, I usually try to treat 9 times (27 day total).

I did mite counts and sticky board drop counts on every hive during treatment - for 2 years. I collected all the data. Based on that data, I now: treat in August (once yearly) & don't count mites. This is what has worked for me, in my area. My bees don't get a brood break due to winter, but they do have a dearth from August till November.

My average mite drop counts would look like this (counted on the 3rd day after each treatment, just prior to the next treatment):
900
900
900
450
300
300
280
320
18

As you can see, the last 2 or 3 treatments seemed to catch a goodly qty of mites, before the drop counts really fell.

I know they say that OAV "stays effective" for 3 days, but my notes showed very little increase in mite drops after about 30 hours post-treatment. Suggesting to me that efficacy drops off quickly.

My data definitely has proven - to me - that a 7-day OAV treatment cycle would not work. Fwiw.

Thanks for sharing this Cool...  Good stuff!!
Title: Re: Varroa checks
Post by: Ben Framed on July 19, 2021, 08:33:37 am
... Treatment day 1 then wait till day 7 retreat. The problem is Varroa exiting their capped cells between days 2 and 6....

I also do 3-day treatment cycles with OAV, for exactly the reason you state. Only, I usually try to treat 9 times (27 day total).

I did mite counts and sticky board drop counts on every hive during treatment - for 2 years. I collected all the data. Based on that data, I now: treat in August (once yearly) & don't count mites. This is what has worked for me, in my area. My bees don't get a brood break due to winter, but they do have a dearth from August till November.

My average mite drop counts would look like this (counted on the 3rd day after each treatment, just prior to the next treatment):
900
900
900
450
300
300
280
320
18

As you can see, the last 2 or 3 treatments seemed to catch a goodly qty of mites, before the drop counts really fell.

I know they say that OAV "stays effective" for 3 days, but my notes showed very little increase in mite drops after about 30 hours post-treatment. Suggesting to me that efficacy drops off quickly.

My data definitely has proven - to me - that a 7-day OAV treatment cycle would not work. Fwiw.

Thanks for sharing this Cool...  Good stuff!!


Adding you show a total of 9 treatments, Am I understanding this correctly? Alan your research is greatly appreciated, especially coming from a fellow member. Thanks for your attention to detail. The last drops say it all. Job well done!
Title: Re: Varroa checks
Post by: Bill Murray on July 19, 2021, 09:19:31 am
Yes, thank you,everyone. This is greatly appreciated. with this info in my toolbox I will change course in a yard close to the house and see how it goes.
Title: Re: Varroa checks
Post by: rast on July 19, 2021, 12:36:21 pm
 Thanks, I had considered 9 days, now will reconsider. Did you state the appx. gram amount used any where?
Title: Re: Varroa checks
Post by: Bill Murray on July 19, 2021, 05:45:51 pm
rast, UF did a study and published a paper on broodbreaks and OAV. I found the outcome interesting to say the least.
https://academic.oup.com/jee/article-abstract/113/2/582/5697464?redirectedFrom=fulltext (https://academic.oup.com/jee/article-abstract/113/2/582/5697464?redirectedFrom=fulltext) Heres the link if your interested.
Also this one on dosage.
https://www.researchgate.net/publication/349318139_Determining_the_dose_of_oxalic_acid_applied_via_vaporization_needed_for_the_control_of_the_honey_bee_Apis_mellifera_pest_Varroa_destructor (https://www.researchgate.net/publication/349318139_Determining_the_dose_of_oxalic_acid_applied_via_vaporization_needed_for_the_control_of_the_honey_bee_Apis_mellifera_pest_Varroa_destructor)
Title: Re: Varroa checks
Post by: Beeboy01 on July 19, 2021, 08:50:20 pm
Coolbees, When you were performing your counts did you notice any lighter colored mites dropping during the last few treatments? When I treated a heavily infested hive I saw a lot of light colored mites about the color of coffee with milk in it after about five treatments three days apart. From what I was able to find out about the Varroa life cycle the lighter color was an indication that the mites were younger and fresh out of the brood cells. 
Title: Re: Varroa checks
Post by: CoolBees on July 20, 2021, 05:54:24 pm
Coolbees, When you were performing your counts did you notice any lighter colored mites dropping during the last few treatments? When I treated a heavily infested hive I saw a lot of light colored mites about the color of coffee with milk in it after about five treatments three days apart. From what I was able to find out about the Varroa life cycle the lighter color was an indication that the mites were younger and fresh out of the brood cells.

Yes - light brown, light red, milky white, and even "clear" colors - most showing up in the later treatment cycles. The early treatment cycles had almost totally "dark" colored mites.
Title: Re: Varroa checks
Post by: CoolBees on July 20, 2021, 06:14:16 pm
Thanks, I had considered 9 days, now will reconsider. Did you state the appx. gram amount used any where?

Somewhere, I got a "scoop" for OA. I think it's 1 gram? ... I use 1/2 scoop per 8-frame brood-nest box - up to 2 full scoops (2 grams?).

Here are some things I found:

Early morning (and late evening) treatments had low drop rates - probably because the bees were still clustered, blocking the flow/spread of OAV.

Mid afternoon treatments needed more treatments - 11 or 12 3-day cycles (i.e. a 3rd brood cycles). This is probably because some/many field bees are carrying mites also, and are nor in the hive at that time.

Mid morning or late afternoon seemed to get the best results/ highest drop rates.

The Application site hole (1/4" hole for Provap applicator) needs to be re-drilled every 2 applications, or so. OA crystals build up around the application hole and block the Vapor from circulating thru the hive properly. This was the #1 cause of low drop counts, mid-application cycle.

Note: I often do a 3-day & then 4-day application cycle - i.e. Sundays and Wednesdays and repeat. This allows me to schedule the rest of my life easier, and seems to work well. I will treat for 4 or 5 weeks o this cycle. Once per year - in my area.
Title: Re: Varroa checks
Post by: rast on July 20, 2021, 09:31:23 pm
 "The Application site hole (1/4" hole for Provap applicator) needs to be re-drilled every 2 applications, or so. OA crystals build up around the application hole and block the Vapor from circulating thru the hive properly. This was the #1 cause of low drop counts, mid-application cycle."
  I keep golf tees stuck in mine.
Title: Re: Varroa checks
Post by: Ben Framed on July 20, 2021, 11:16:45 pm
Quote
The Application site hole (1/4" hole for Provap applicator) needs to be re-drilled every 2 applications, or so. OA crystals build up around the application hole and block the Vapor from circulating thru the hive properly. This was the #1 cause of low drop counts, mid-application cycle.

I keep golf tees stuck in mine.

My application hole are slightly larger than golf tees. I was concerned that propolis may be added in these loose areas and possibly blocking the vapor as Alan has experienced with vapor crystals. My go to now is dowels the size of my applicator tube on my OAV vaporizer. I make sure they are long enough to become flush on the inside of the hole yet sticking out a couple of inches on the outside used as a grip in removing for the next application. I accomplished this by using a 'pattern' dowel with a circle marked depth reminder using a sharpie, letting me know the dowel is in deep when the mark or the dowel reached the outside edge of the inlet hole of the hive. Each dowel plug is marked this way.
Title: Re: Varroa checks
Post by: Beeboy01 on July 20, 2021, 11:26:07 pm
Coolbees, thanks for the reply, I've always wondered if finding immature mites near the end of the treatments was a common occurrence.  It might be a good indicator that the treatment was a success.

Back in 2018 I had a heavily infested hive and spent most of the summer treating and counting mite drops.  I haven't posted the graph of the data for a while so here it is again.
[ You are not allowed to view attachments ]
Title: Re: Varroa checks
Post by: CoolBees on July 21, 2021, 01:33:07 pm
Just to clarify - the buildup of OA crystals that I'm referring to, occurred about 2-3 inches into the hive around the application hole. I observed this be taking a hive apart and looking at the bottom board. My application hole is drilled thru the back- center of the bottom board, just below the bottom box.

I found I have to run a fairly long drill into the hive to clear the buildup of crystals.

A dowel that "fits flush" on the inside, will not fix or prevent this problem. This is my experience, just FWIW.
Title: Re: Varroa checks
Post by: Beeboy01 on July 21, 2021, 01:46:34 pm
I treat using a OA wand through the screened bottom board and have seen a deposit of crystals on the tray the next day where the wand head was sitting. I always thought that the vapor was condensing and crystallizing directly over the wand during application. Sounds similar to  what you are describing with the Provap.
Title: Re: Varroa checks
Post by: BeeMaster2 on July 21, 2021, 06:13:15 pm
Coolbees,
My OAV vaporizer has a 2 inch copper tube that slides of the hive and prevents the hole from being blocked up. Is it possible to modify your unit?
Jim Altmiller
Title: Re: Varroa checks
Post by: rast on July 22, 2021, 09:51:08 am
 Coolbees,
   We use the same application hole location, but this is the first that I have heard of a buildup like that. My nozzle is 1 5/8" long with a 3/32+ ID which gives it some velocity. There is also an uptilt to the nozzle due to hole diameter so it is not shooting directly on any thing. Interesting and something to look for when I see a bottom board Saturday.
Title: Re: Varroa checks
Post by: Ben Framed on July 22, 2021, 10:40:29 am
Quote

My application hole are slightly larger than golf tees. I was concerned that propolis may be added in these loose areas and possibly blocking the vapor as Alan has experienced with vapor crystals. My go to now is dowels the size of my applicator tube on my OAV vaporizer. I make sure they are long enough to become flush on the inside of the hole yet sticking out a couple of inches on the outside used as a grip in removing for the next application. I accomplished this by using a 'pattern' dowel with a circle marked depth reminder using a sharpie, letting me know the dowel is in deep when the mark or the dowel reached the outside edge of the inlet hole of the hive. Each dowel plug is marked this way.

Just to clarify - the buildup of OA crystals that I'm referring to, occurred about 2-3 inches into the hive around the application hole. I observed this be taking a hive apart and looking at the bottom board. My application hole is drilled thru the back- center of the bottom board, just below the bottom box.

I found I have to run a fairly long drill into the hive to clear the buildup of crystals.

A dowel that "fits flush" on the inside, will not fix or prevent this problem. This is my experience, just FWIW.

Thanks for the clarification Cool. In that case dowels will not make a difference in the circumstances as you are pointing out. Your information is something I will pay special attention to after my next rounds of treatments. Thanks !
Title: Re: Varroa checks
Post by: Ben Framed on July 26, 2021, 12:44:10 am
To the credit of CoolBees and Beeboy01 adding rast. I am posting this video of some very heavy hitters in bee research whom I greatly respect and admire, which the information of the video came out just today! You two have posted private studies that actually go beyond what is stipulated by experts here as demonstrated by your charts. Please understand, I am in no wise scrutinizing the great researchers, as we are ALL learning together as we go and they are doing GREAT WORK. As a universal team if you will. Beekeepers and researchers alike in the fight of Varroa Destructor. If they had treated in 3 day intrivitals instead of 5 and 9 treatments instead of 7,  Or even the 3 day 7 treatments as rast, I am confident and they would have come up with similar results as you Alan 'Coolbees' and 'Beeboy01'. Maybe the three day is the key? I am thinking Mr Binnie was kind of leading in this direction going by his questioning.


https://youtu.be/WbqdyufEQNM
Title: Re: Varroa checks
Post by: mark on July 28, 2021, 10:01:00 pm
https://www.youtube.com/watch?v=4Sy5fNDvxgg
Title: Re: Varroa checks
Post by: Ben Framed on July 28, 2021, 11:07:35 pm
Mark I had this basic discussion with Cameron Jack, related to his thoughts of 4 g instead of 1 or 2, as discussed here in in the first part of your video. I got in touch with him after several of us here at Beemaster were having a discussion, some time ago, on the topic: "OAV too hot?"

After watching  part 2, the video that you posted, studying his chart, I am sustained in my confidence that Coolbees is on target with his 3 day / 9 treatment program.

We shall in time, see about the OAV strips mentioned here as the study progresses? I hope they work!


Title: Re: Varroa checks
Post by: rast on July 30, 2021, 11:03:12 pm
 Regarding discussion starting post #21, I did not see any OA build up on my bottom boards (solid). I'm proud that I remembered to look.
Title: Re: Varroa checks
Post by: mark on August 01, 2021, 11:22:57 am
https://www.youtube.com/watch?v=RN0regj4rPw
anxious to see the results.   
Title: Re: Varroa checks
Post by: Ben Framed on August 01, 2021, 09:49:40 pm
Topic:
"Has Anyone Used the Randy Oliver Shop Towel Mite Treating Method?"


Mark you might find this Beemaster topic interesting as well.



Title: Re: Varroa checks
Post by: mark on August 01, 2021, 10:34:47 pm
i surely do ben.  it's all interesting which is why i followed up your post from bob binnie with the next 2 parts.you actually beat me to the punch but i was pleased to see it was already posted. he's one of my favorite videos to watch.  i actually did my first alcohol wash this year and didn't find any mites. pleased but conflicted for killing all those bees for nuthin.
Title: Re: Varroa checks
Post by: Ben Framed on October 03, 2021, 12:17:30 pm
Bobbee started this topic a year ago. How are things concerning varroa in your bee yards since this topic was begun?
Title: Re: Varroa checks
Post by: Beeboy01 on October 22, 2021, 12:07:20 am
I'm still treating every third or fourth day for eight treatments in my yard using a wand. So far the mite drop has dropped quickly during the last half of the treatments. My last treatment period was late August into September between the Cabbage Palm and Brazilian Pepper flows. My next treatment period will be at the end of December  into January trying to catch whatever natural brood break if any occurs here in Florida.

  Just got my monthly copy of Bee Culture and in the front question and answer section OAV was blasted as detrimental to the health of the bees with genetic modification of the bee's RNA the upcoming solution. It kind of surprised me considering how long OAV has been used in Europe with no noted problems.   
Title: Re: Varroa checks
Post by: NigelP on October 22, 2021, 04:25:34 am
Yup that is surprising.
Interesting that many of you need to vape 8 or 9 times. Quite labour intensive.
Over here I do 4 vapes at 5 day intervals to try to catch all the emerging mites from the sealed cells.  It's usually enough, except for an occasional hive that just keeps dropping mites and mites and mites. In the past have done several more vapes on these rogue hives but now just add Amitraz strips to them to save me the drive and extra work.
I'm using a sublimox and have designed an eke with a clear top and hole for sublimox nozzle. You are then "blowing" sublimated OA into an empty space that rapidly fills the rest of the hive as it descends downwards.  It does require the crown boards being removed but is a very efficient way of distributing vaporized OA and very easy to remove the build up of crystals near the hole in the eke.

Many in the UK have been using OA strips this past few years but with mixed results. Some swear by them, some swear at them.  When it gets this hit and miss with a treatment I'll stay clear of it.
Title: Re: Varroa checks
Post by: Ben Framed on October 22, 2021, 10:37:11 am
Nigel I can see where it is surprising to you, not being the traditional approach. It was for me as well until Beeboy01 did an experiment back a couple years ago, all the while keeping us updated of the findings as he went along. Coolbees did a similar experiment reporting his findings here on this very same topic, reporting way back in Reply #13.  (I realize there has been a lot of ground covered in this interesting topic). Go back and take a look at his interesting findings.

I tried to find beeboy topic as well and with the intention of posting its reference here for you but so far I have not found it. Good stuff uncovered here by both of our fellow members! I am glad you have joined us here at beemaster as well. Your input is very helpful and appreciated!!!

Phillip
Title: Re: Varroa checks
Post by: Beeboy01 on October 22, 2021, 11:49:55 am
Nigel, I try to cover two complete mite life cycles with my treatment regime. Since mites spend about ten days in the capped brood during their breeding cycle I look at a minimum of 20 days worth of OAV exposure to be my target for a total treatment. I decided on a three or four day period between treatments from research which said that OAV crystals are removed from the hive by the bees in that time period so extending the time between treatments will only allow the breeder mites time to move over to another brood cell and continue the breeding cycle. A shorter period between treatments will keep the level of OAV crystal higher and more stable in the hive which increases it's exposure to the mite population and break the mite breeding cycle similar to treating the ground under the hives to break the small hive beetle life cycle by targeting their larval form.

   One thing that hasn't been brought up concerning OAV is the type of applicator used and how much is applied to each hive during a treatment. I am using a wand with a 1/4 tea spoon of oxalic acid powder which is about two grams applied through the screened bottom board. The application time takes about five minutes for complete vaporization and I'm usually treating a double ten frame deep. I've always wondered on the dose strength and application time with equipment like the ProVap and other similar designed applicators which from my understanding apply the OAV directly into the hive body and brood area. I would think that a quicker application using a larger amount of oxalic acid directly into the brood area would have a longer "half life" and be more effective in the hive but I haven't been able to find any research covering it. Of course there would have to be a point of diminishing returns with larger doses along with potential damage to the bees.
 
  I also agree with you that my treatment regime is labor intensive and not feasible for any large scale operation. I'm just a hobby bee keeper and run about 5 hives which are kept behind my shop which allows me to treat more often than most. 
Title: Re: Varroa checks
Post by: NigelP on October 22, 2021, 02:29:01 pm
Nigel I can see where it is surprising to you, n
Ben, the surprising bit was the magazine article suggesting OA caused problems with bees. It can if dribbled in a solution, but to date I'm not aware of any serious affects recorded from vaporized OA.
Beeboy1, thanks for the clarification, same ideas here,  I just cover less cycles as less work (lazy moi  :happy:). It's impossible to kill all varroa, my aim is to keep numbers low and below a supposed threshold (whatever that happens to be) that causes serious issue for the bees.

Title: Re: Varroa checks
Post by: Ben Framed on October 22, 2021, 03:17:58 pm
Nigel I can see where it is surprising to you, n
Ben, the surprising bit was the magazine article suggesting OA caused problems with bees. It can if dribbled in a solution, but to date I'm not aware of any serious affects recorded from vaporized OA.


I know I was surprised as well. I'm not so sure about that part just yet......???
Title: Re: Varroa checks
Post by: NigelP on October 22, 2021, 03:29:05 pm
   One thing that hasn't been brought up concerning OAV is the type of applicator used and how much is applied to each hive during a treatment. I am using a wand with a 1/4 tea spoon of oxalic acid powder which is about two grams applied through the screened bottom board.
A very important point.
I (rightly or wrongly) describe the OA vaporisers as of two type. Passive, as in the pan under mesh floor or inside hive floor under frames. Here  you rely on the sheer volume of vapour produced to fill all the hive.
The other type I describe as active. Like the sublimox I use, or any vaporiser where the vapour is forced out of a confined space under pressure These in my opinion are quicker and more efficient as they are blowing and forcing the vapour throughout the hive. With the proviso that the jet of vapour is not hitting a solid surface immediately after it leaves the nozzle.
I estimate at just over  a minute per hive using these types, 30 seconds for sublimation of 2gms of OA and another 30 to let it settle down wards from my eke.
Title: Re: Varroa checks
Post by: Ben Framed on October 22, 2021, 04:27:21 pm
   One thing that hasn't been brought up concerning OAV is the type of applicator used and how much is applied to each hive during a treatment. I am using a wand with a 1/4 tea spoon of oxalic acid powder which is about two grams applied through the screened bottom board.
A very important point.
I (rightly or wrongly) describe the OA vaporisers as of two type. Passive, as in the pan under mesh floor or inside hive floor under frames. Here  you rely on the sheer volume of vapour produced to fill all the hive.
The other type I describe as active. Like the sublimox I use, or any vaporiser where the vapour is forced out of a confined space under pressure These in my opinion are quicker and more efficient as they are blowing and forcing the vapour throughout the hive. With the proviso that the jet of vapour is not hitting a solid surface immediately after it leaves the nozzle.
I estimate at just over  a minute per hive using these types, 30 seconds for sublimation of 2gms of OA and another 30 to let it settle down wards from my eke.

Nigel, You might be interested in a topic posted here some time ago.  Title: "OAV too hot?"
Some interesting twist there...
Title: Re: Varroa checks
Post by: NigelP on October 22, 2021, 04:55:40 pm
Search for "OAV too hot?" retuned no hits Ben....if you could link it up, be interested to see what what was said
Title: Re: Varroa checks
Post by: Beeboy01 on October 22, 2021, 05:59:49 pm
Here's a quote found on page 15 of the Oct 2021 Bee Culture form Jerry Hayes

 " Lets say you have a parasite the size of a rat. You can't get it off and I can't help get it off either. So we come up with a plan. I'll lock you in your closet and we will vaporize a caustic acid in the closet with you. We do it. I open the door and the parasite the size of a rat has fallen off. Good deal. But you have burns on  your skin, your nasal passages are burned along with the trachea from breathing the stuff. Some of your eyebrows are burned off and your eyes are red and watering because of the acid burn"

Anyways Jerry continues on in the Study Hall section about RNAi as a control for the mites by using genetic modification which is being developed by Bayer Pharmaceuticals.

   When I first move to Florida I had the honor of meeting Jerry when he was the local apiary inspector for the state of Florida and I don't mean this post to show any disrespect to the man, he's probably forgotten more than I know when it comes to bees.  I'm just wondering if a statement like this could drive some bee keepers away from oxalic acid treatments causing disastrous results to their bees. 
Title: Re: Varroa checks
Post by: Ben Framed on October 22, 2021, 06:02:31 pm
Search for "OAV too hot?" retuned no hits Ben....if you could link it up, be interested to see what what was said

Sending a PM

Title: Re: Varroa checks
Post by: Ben Framed on October 22, 2021, 06:39:09 pm
I have read the hard exoskeleton of bees are not affected, nor the breathing passages. Where in contrast the soft tissue of varroa is the advantage of OAV. I wish I could find that. It is here somewhere in the archives along with links.
Title: Re: Varroa checks
Post by: CoolBees on October 22, 2021, 06:39:24 pm
.... But you have burns on  your skin, your nasal passages are burned along with the trachea from breathing the stuff. Some of your eyebrows are burned off and your eyes are red and watering because of the acid burn"

Anyways Jerry continues on in the Study Hall section about RNAi as a control for the mites by using genetic modification which is being developed by Bayer Pharmaceuticals.
...

...  I'm just wondering if a statement like this could drive some bee keepers away from oxalic acid treatments causing disastrous results to their bees.

I have a hard time with this analysis of Jerry's. Bees aren't humans - the comparison is invalid in so many ways. Further, bees target and harvest oxalic acid on their own, or so I've read. I'd guess your conclusion was correct. No one makes money off of OA, it's too cheap. There are many that would like to find a "more profitable" (for them) solution to the Mite problem.
Title: Re: Varroa checks
Post by: rast on October 22, 2021, 10:00:28 pm
Also having met and listened to him, Jerry never did like OAV from the get go.
Title: Re: Varroa checks
Post by: Ben Framed on October 23, 2021, 02:13:55 am
For any of you newer members the following article goes hand and hand with this topic, (a sister topic if you will allow), in case you may be interested.

Phillip

Has Anyone Used the Randy Oliver Shop Towel Mite Treating Method?
Title: Re: Varroa checks
Post by: NigelP on October 23, 2021, 05:03:59 am
Here's a quote found on page 15 of the Oct 2021 Bee Culture form Jerry Hayes

 " Lets say you have a parasite the size of a rat. You can't get it off and I can't help get it off either. So we come up with a plan. I'll lock you in your closet and we will vaporize a caustic acid in the closet with you. We do it. I open the door and the parasite the size of a rat has fallen off. Good deal. But you have burns on  your skin, your nasal passages are burned along with the trachea from breathing the stuff. Some of your eyebrows are burned off and your eyes are red and watering because of the acid burn"

Thanks for that Beeboy01, Looks like total rubbish written by a supposed expert, I'll bet the farm he provides no evidence of what he claims.  It's been tricky to get definitive prove of how vaporised OA crystals kills varroa, but it is thought that OA vapors enter through the soft pads of the mite's feet and travels to the blood stream, effectively acidifying the mite and thus killing them. It is also thought that it destroys parts of the mite's mouth. However it works, it decimates them.
There is little evidence of of vaporised OA having any major detrimental effect on bees and the RNAi treatments are still a pipe dream.
But OA vaporisation is "hot" topic. I had to resign from a local association as they refused to let me talk about OA sublimation in a talk I was giving to the members. Naturally I refused to back down.
Title: Re: Varroa checks
Post by: Beeboy01 on October 23, 2021, 04:03:27 pm
Nigel, I try to keep my mouth shut about different mite treatments but sometimes when an expert spouts something that is baloney I speak out. I've been bee keeping for over 30 years and remember it before mites. Since they arrived I've tried just about all the commercially available treatments and really think OAV is the best but as was mentioned the big companies can't make any money off it. Even suggesting shortening the intervals between treatments gets a large blow back in the local club I'm a member of.     
Title: Re: Varroa checks
Post by: Ben Framed on October 23, 2021, 05:42:27 pm
Beeboy I appreciate you speaking out. This is how we all learn. Sometimes we speak out with good information, sometimes our references might be disputed;  but all in all it?s healthy in my opinion. I applaud you. You are very knowledgeable and I have learned a lot of good things from you. Keep up the good work!

Phillip
Title: Re: Varroa checks
Post by: Beeboy01 on October 23, 2021, 09:55:24 pm
Ben Framed, thanks for the complement, I'm just a hobby bee keeper and i know that I don't know a lot. Trying to shake off a day at the local flea market selling honey and educating people about local honey and bee keeping. Man it was hard work explaining where the different flavors of honey come from. I had a good year with over 30 gallons of mixed honey and need to move some to make room. Looks like I'll be a regular at the flea market for a few months. Not complaining, it's just another aspect of bee keeping I haven't have had to do before.